Hypospadias - Information Overview

Hypospadias is a congenital malformation of the penis, characterized by a split in the posterior wall of the urethra in the interval from the head to the perineum, a split in the ventral edge of the preputial sac, ventral curvature of the shaft of the penis, or the presence of one of the listed signs.

Over the past 30 years, the incidence of births of children with hypospadias has increased from 1:450-500 to 1:125-150 newborns. The increase in the incidence of births of children with various forms of hypospadias and the high incidence of postoperative complications, which reaches 50%, have led to a search for optimal methods of surgical treatment of this urological disease throughout the world.

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Causes hypospadias

The causes of hypospadias are pathological changes in the endocrine system, as a result of which the external genitalia of the male fetus are insufficiently virilized. At present, the participation of the hereditary factor in the development of hypospadias in children has been proven. According to urologists, the frequency of familial hypospadias varies within 10-20%. At present, many syndromes are known in which one or another form of violation of sexual differentiation of the external genitalia occurs, leading to the formation of hypospadias in boys.

Sometimes, making a correct diagnosis is a difficult task, the wrong solution of which can lead to erroneous tactics in the treatment process and, in some cases, to a family tragedy. In this regard, identifying the level at which an error occurred in the complex process of formation of the genitals is a decisive moment at the stage of diagnosis in a patient with hypospadias.

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Forms

The primary gonads are formed between the 4th and 5th week of fetal development. The presence of the Y chromosome ensures the formation of the testes. It is assumed that the Y chromosome codes for the synthesis of the Y-antigen protein, which facilitates the transformation of the primary gonad into testicular tissue. Embryogenic phenotypic differences develop in two directions: the internal ducts and external genitalia differentiate. At the earliest stages of development, the embryo contains both female (paramesonephric) and male (mesonephric) ducts.

The internal genitalia are formed from the Wolffian and Müllerian ducts, which are located close to each other in the early stages of embryonic development in both sexes. In male embryos, the Wolffian ducts give rise to the epididymis, vas deferens, and seminal vesicles, while the Müllerian ducts disappear. In female embryos, the Müllerian ducts give rise to the fallopian tubes, uterus, and upper vagina, while the Wolffian ducts regress. The external genitalia and urethra in fetuses of either sex develop from a common rudiment - the urogenital sinus and genital tubercle, genital folds, and elevations.

Fetal testicles are capable of synthesizing a protein substance (anti-Müllerian factor), which reduces paramesonephric ducts in a male fetus. In addition, starting from the 10th week of intrauterine development, the fetal testicle, first under the influence of human chorionic gonadotropin (hCG), and then its own luteinizing hormone (LH), synthesizes a large amount of testosterone, which affects the indifferent external genitalia, causing their masculinization. The genital tubercle, enlarging, is transformed into the penis, the urogenital sinus - into the prostate and the prostatic part of the urethra, and the genital folds merge. forming the male urethra. The meatus is formed by retraction of the epithelial tissue into the head and merges with the distal end of the forming urethra in the area of the scaphoid fossa. Thus, by the end of the first trimester, the final formation of the genitals occurs.

It should be noted that for the formation of internal male genital organs (genital ducts), the direct action of testosterone is sufficient, while for the development of external genital organs, the influence of its active metabolite dihydrotestosterone, formed directly in the cell under the influence of a specific enzyme - 5-a-reductase, is necessary.

Currently, many classifications of hypospadias have been proposed, but only the Barcat classification allows for an objective assessment of the degree of hypospadias, since the assessment of the form of the defect is carried out only after surgical correction of the penile shaft.

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Barcat's classification of hypospadias

• Anterior hypospadias.
  • Capitate.
  • Crown.
  • Fore-stemmed.
• Average hypospadias.
  • Medium-sized.
• Posterior hypospadias.
  • Posterior trunk.
  • Barrel-shaped.
  • Scrotal.
  • Perineal.

Despite its obvious advantage, the Barcat classification has a significant drawback. It does not include a special form of this anomaly - hypospadias without hypospadias, which is sometimes called chord-type hypospadias. However, based on the pathogenesis of the disease, "hypospadias without hypospadias" is a more appropriate term for this type of anomaly, since in some cases the cause of ventral deviation of the penile shaft is exclusively dysplastic skin of the ventral surface without a pronounced fibrous chord, and sometimes the fibrous chord is combined with deep dysplastic processes in the area of the urethra itself.

In this regard, it is logical to expand the Barcat classification by adding a separate nosological unit - hypospadias without hypospadias.

In turn, there are four types of hypospadias without hypospadias:

• Type I - ventral deviation of the penile shaft is caused exclusively by dysplastic skin of its ventral surface;
• Type II - curvature of the penis shaft is caused by a fibrous chord located between the skin of the ventral surface of the penis and the urethra;
• Type III - curvature of the penis shaft is caused by a fibrous chord located between the urethra and the cavernous bodies of the penis;
• Type IV results in curvature of the penis shaft due to a pronounced fibrous chord in combination with a sharp thinning of the wall of the urethra (dysplasia of the urethra).

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Diagnostics hypospadias

A deep clinical analysis, including a full range of urodynamic tests, as well as X-ray urological, radioisotope and endoscopic diagnostics of hypospadias, allows us to determine the tactics of further treatment of the patient.

Sometimes in the practice of a pediatric urologist there are situations when, due to diagnostic errors, a child with a 46 XX karyotype but with virile genitals is registered in the male gender, and a child with a 46 XY karyotype but with feminized genitals is registered in the female gender. The most common cause of problems in this group of patients is erroneous karyotyping or its absence at all. A change in the passport gender of children at any age is associated with severe psychoemotional trauma for parents and the child, especially if the patient's psychosexual orientation has already occurred.

There are cases when girls with congenital hyperplasia of the adrenal cortex and clitoral hypertrophy were diagnosed with hypospadias, with all the consequences that entails, and, on the contrary, a boy with testicular feminization syndrome was raised as a girl until puberty. It is often during puberty that the absence of timely menstruation attracts the attention of specialists, but by this time the child has already formed a sexual self-awareness, or, in other words, a social gender.

Thus, any child with abnormalities of the external genitalia should be examined in a specialized institution. In addition, even children with unchanged genitals should undergo ultrasound examination of the pelvic organs immediately after birth. Currently, more than 100 genetic syndromes are known that are accompanied by hypospadias. Based on this fact, it is advisable to consult a geneticist, who in some cases helps to clarify the diagnosis and focus the attention of urologists on the features of the manifestation of a particular syndrome during treatment.

In solving this problem, the endocrinological aspect is most important, since the causes of hypospadias are based on disorders of the endocrine system, which, in turn, explains the combination of hypospadias with micropenia, scrotal hypoplasia, various forms of cryptorchidism and disorders of obliteration of the vaginal process of the peritoneum (inguinal hernia and various forms of hydrocele and spermatic cord).

In some cases, children with hypospadias are found to have congenital malformations of the kidneys and urinary tract, so ultrasound of the urinary system should be performed on patients with any form of hypospadias. Urologists most often encounter VUR, as well as hydronephrosis, ureterohydronephrosis and other abnormalities in the development of the urinary system. When hypospadias is combined with hydronephrosis or ureterohydronephrosis, plastic surgery of the affected segment of the ureter is initially performed, and only after 6 months is it advisable to perform hypospadias treatment. If a patient with hypospadias is found to have vesicoureteral reflux, its cause must be clarified and eliminated.

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Treatment hypospadias

Understanding the pathogenesis of hypospadias determines the correct tactics of the surgeon and contributes to the successful treatment of hypospadias.

Treatment of hypospadias is carried out exclusively by surgery. Before surgery, it is necessary to conduct a comprehensive examination of the patient, allowing to differentiate hypospadias from other disorders of sex formation. For this purpose, in addition to a general examination of the patient, karyotyping is mandatory (especially in cases where hypospadias is combined with cryptorchidism).

Surgical treatment of hypospadias has the following goals:

• complete straightening of the curved cavernous bodies, providing an erection sufficient for sexual intercourse;
• creation of an artificial urethra from tissues devoid of hair follicles of sufficient diameter and length without fistulas and strictures;
• urethroplasty using the patient's own tissue with adequate blood supply, ensuring the growth of the created urethra as the cavernous bodies grow physiologically;
• displacement of the external opening of the urethra to the top of the head of the penis with a longitudinal arrangement of the meatus;
• creating free urination without deviation or splashing of the stream;
• maximum elimination of cosmetic defects of the penis for the purpose of psycho-emotional adaptation of the patient in society, especially when entering into sexual relations.

After the introduction of the latest scientific achievements into modern medicine, wide opportunities have opened up to reconsider a number of concepts in penile plastic surgery. The availability of microsurgical instruments, optical magnification, and the use of inert suture material have made it possible to minimize surgical trauma and perform successful operations on children from 6 months. Most modern urologists around the world prefer one-stage correction of hypospadias at an early age. Attempts by some urologists to perform one-stage surgery on newborn boys or on children aged 2-4 months have not justified themselves. Most often, hypospadias correction is performed at 6-18 months, since at this age the ratio of the sizes of the cavernous bodies and the supply of plastic material (the skin of the penis itself) is optimal for performing the surgical intervention.

In addition, at this age, performing corrective surgeries has a minimal effect on the child's psyche. As a rule, the child quickly forgets the negative aspects of postoperative treatment, which does not affect his or her personal development in the future. Patients who have undergone multiple surgeries for hypospadias often develop an inferiority complex.

All types of developed technologies of surgical interventions can be conditionally divided into three groups:

• methods using the penis's own tissues;
• methods using patient tissue located outside the penis;
• methods using advances in tissue engineering.

The choice of method often depends on the technical equipment of the clinic, the experience of the surgeon, the age of the patient, the effectiveness of preoperative preparation and the anatomical features of the genitals.

Algorithm for choosing a method of surgical treatment of hypospadias

The choice of surgical treatment method directly depends on the number of methods that the surgeon has mastered, since a number of methods can be used with equal success for the same form of defect. Sometimes meatotomy is enough to solve the problem, and sometimes complex microsurgical operations are required, so the determining factors for choosing a method are as follows:

• location of the hypospadic meatus;
• narrowing of the meatus;
• preputial sac size;
• the ratio of the sizes of the cavernous bodies and the skin of the penis;
• dysplasia of the skin of the ventral surface of the penis;
• degree of curvature of the cavernous bodies;
• penis head size;
• depth of the groove on the ventral surface of the glans penis;
• degree of rotation of the penis;
• penis size;
• the presence of adhesions of the foreskin and the degree of their severity;
• penis shaft topic, etc.

Currently, there are more than 200 known methods of surgical correction of hypospadias. However, this article presents operations that have a fundamentally new direction in plastic genital surgery.

The first attempt at surgical correction of hypospadias was made by Dieffenbach in 1837. Despite the interesting idea of the operation itself, unfortunately, it was not successful.

The first successful attempt at urethroplasty was performed by Bouisson in 1861 using rotated scrotal skin.

In 1874, Anger used an asymmetrical displaced flap from the ventral surface of the penile shaft to create an artificial urethra.

In the same year, Duplay used a tubularized ventral skin flap for urethral plastic surgery according to the Thiers principle, proposed for the correction of trunk epispadias in the 1960s. The operation was performed in one or two stages. In cases of distal hypospadias, the operation was performed in one stage, in cases of proximal forms, plastic surgery of the urethra was performed several months after preliminary straightening of the penile shaft. This operation has become widespread throughout the world, and at present, many surgeons who do not have the technique of one-stage hypospadias correction use this technology.

In 1897, Nove and Josserand described a method for creating an artificial urethra using an autologous free skin flap taken from a non-hairy part of the body surface (inner surface of the forearm, abdomen).

In 1911, L. Ombredan attempted a full-stage correction of the distal form of hypospadias, in which an artificial urethra was created using the flip-flap principle using the skin of the ventral surface of the penis. The resulting wound defect was closed with a displaced split preputial flap using the principle developed by Thiersch.

In 1932, Mathieu, using the Bouisson principle, performed a successful correction of the distal form of hypospadias.

In 1941, Humby proposed using the buccal mucosa to create a new urethra.

In 1946, Cecil, using the principle of Duplay and Rosenberger of 1891, performed a three-stage plastic surgery of the urethra in the trunk-scrotal form using a trunk-scrotal anastomosis at the second stage of the surgical procedure.

In 1947, Memmelaar described a method for creating an artificial urethra using a free flap of bladder mucosa. In 1949, Browne described a method of distal urethroplasty without closing the internal surface of the artificial urethra, relying on independent epithelialization of the non-tubularized surface of the artificial urethra.

The founder of a number of operations aimed at creating an artificial urethra using a vascular bundle was Broadbent, who in 1961 described several variants of such operations.

In 1965, Mustarde developed and described an unusual method of urethroplasty using a tubularized rotated ventral skin flap with tunnelization of the glans penis.

In 1969-1971 N. Hodgson and Asopa developed the idea of Broadbent and created a number of original technologies that made it possible to correct severe forms of hypospadias in one stage.

In 1973, Durham Smith developed and implemented the principle of a mixed deepepithelial flap, which subsequently became widespread throughout the world for the correction of hypospadias and excision of urethral fistulas.

In 1974, Cities and MacLaughlin first used and described the artificial erection test, in which sodium chloride (sodium chloride isotonic injection solution 0.9%) was injected intracavernously after a tourniquet was placed on the base of the penis. This test allowed an objective assessment of the degree of curvature of the penile shaft.

In 1980, Duckett described a variant of one-stage hypospadias correction using the skin of the inner leaflet of the prepuce on a vascular pedicle. In 1983, Koyanagi described an original method of one-stage correction of the proximal form of hypospadias with a double vertical urethral suture.

In 1987, Snyder developed a method of urethroplasty using the inner leaf of the prepuce on a vascular pedicle using the principle of two flaps, or onlay urethroplasty.

In 1989, Rich applied the principle of longitudinal dissection of the ventral flap for distal hypospadias in combination with the Mathieu technique, performing urethroplasty with less tissue tension, thereby reducing the likelihood of postoperative complications.

In 1994, Snodgrass developed the idea further by using the same ventral surface dissection technique in combination with the Duplay method.

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Technique of operation

To provide technical assistance in the surgical correction of hypospadias, the urologist must have a thorough knowledge of the anatomy of the penis. This knowledge allows for the optimal straightening of the cavernous bodies, cutting out a skin flap that is supposed to be used to create an artificial urethra while preserving the vascular bundle, and closing the wound surface without damaging important anatomical structures. Underestimation of this problem can lead to serious complications, including disability. Successful treatment of hypospadias largely depends on technical equipment. As a rule, for the surgical correction of hypospadias, urologists use a binocular magnifying glass with 2.5-3.5-fold magnification or a microscope, as well as microsurgical instruments. Most often, a 15-mm abdominal scalpel is used, anatomical and surgical tweezers with a minimum tissue capture area, an atraumatic needle holder, "hummingbird" tweezers, small single- and double-pronged hooks, and absorbable monofilament atraumatic suture material 6 0-8 0. During the operation, crushing of the tissues used to create the artificial urethra should be avoided. For this purpose, small hooks or microsurgical retractors should be used. For long-term fixation of tissues in a certain position, it is advisable to use holding threads that do not cause damage to the skin flap.

When correcting any form of hypospadias, it is desirable to perform a complete mobilization of the cavernous bodies in the space between the superficial fascia of the penis and the Buck fascia. This manipulation allows for a complete revision of the cavernous bodies and careful excision of the fibrous chord, which even in distal forms of hypospadias can be located from the head to the penoscrotal angle, limiting further growth of the penis. Mobilized skin of the penis allows for a freer stage of closure of the cavernous bodies, eliminating the possibility of tissue tension. One of the main principles of plastic surgery of the genitals, contributing to the achievement of a successful result, remains the principle of freely laid flaps without tissue tension.

Sometimes after mobilization of the penile skin, signs of microcirculation disorder in the flap are noted. In these cases, the stage of urethral plastic surgery should be postponed until the next time, or, after performing urethral plastic surgery, the area of ischemic tissue should be shifted away from the vascular pedicle that feeds the urethra, in order to avoid vascular thrombosis.

After completion of the urethral plastic surgery stage, it is advisable to shift the line of subsequent sutures to prevent the formation of urethral fistulas in the postoperative period. This technique was used by Thiersch more than 100 years ago to correct the trunk form of epispadias.

Most urologists agree that during the surgical procedure it is necessary to minimize the use of an electrocoagulator or use minimal coagulation modes. Some surgeons use a 0.001% solution of epinephrine (adrenaline) to reduce tissue bleeding. Spasm of peripheral vessels in some cases prevents an objective assessment of the condition of skin flaps and can lead to erroneous tactics during surgery. It is much more effective to use a tourniquet applied to the base of the cavernous bodies in order to achieve the same effect. However, it should be noted that it is necessary to remove the tourniquet from the cavernous bodies for a while every 10-15 minutes. During the operation, it is recommended to irrigate the wound with antiseptic solutions. Sometimes urologists use a single daily dose of a broad-spectrum antibiotic in a dose appropriate for age for prophylactic purposes.

At the end of the surgical procedure, an aseptic dressing is applied to the penis. Most surgeons tend to use a dressing with glycerol (glycerin) in combination with a porous elastic bandage. An important point is the application of a loose gauze bandage soaked in sterile glycerol (glycerin) in one layer in a spiral from the head to the base of the penis. Then, a thin porous elastic bandage (for example, a 3 M Conat bandage) is applied over the gauze bandage. A strip 20-25 mm wide is cut from the bandage. Then, using the same principle, one layer of bandage is applied in a spiral from the head to the base of the penis. There should be no tension on the bandage during the application of the bandage. It should only repeat the contours of the penis shaft. This technique allows maintaining adequate blood supply in the postoperative period, while limiting the increasing swelling of the penis. By the 5th-7th day of the postoperative period, the swelling of the penis gradually decreases, and the bandage shrinks due to its elastic properties. The first change of the bandage is usually made on the 7th day if it is not soaked with blood and retains its elasticity. The condition of the bandage is assessed visually and by palpation. A bandage soaked in blood or lymph dries quickly and does not perform its function. In this case, it should be changed, pre-wetting it with an antiseptic solution and holding it for 5-7 minutes.

Urine diversion in the postoperative period

An important aspect in plastic surgery of the genitals remains the diversion of urine in the postoperative period. Over the long history of genital surgery, this problem has been solved by various methods - from the most complex drainage systems to banal transurethral diversion. Today, most urologists consider it necessary to drain the bladder for a period of 7 to 12 days.

Many urologists use cystostomy drainage in the postoperative period, sometimes in combination with transurethral diversion. Some authors consider puncture urethrostomy to be the optimal method for solving this problem, as it ensures adequate urine drainage.

The vast majority of urologists consider effective urine diversion, which allows the dressing to be kept on the penis without contact with urine for a long time, to be an essential component of a set of measures aimed at preventing possible complications.

Many years of experience in surgical correction of hypospadias objectively proves the rationality of using transurethral urinary diversion in patients with any form of defect.

An exception may be patients in whom tissue engineering achievements were used to create an artificial urethra. In this group of patients, it is logical to use combined urinary diversion - puncture cystostomy in combination with transurethral diversion for up to 10 days.

The optimal catheter for bladder drainage is a urethral catheter with end and side openings No. 8 CH. The catheter should be inserted into the bladder no deeper than 3 cm to prevent involuntary contractions of the detrusor and urine leakage.

It is not recommended to use catheters with a balloon, which causes irritation of the bladder neck and constant contraction of the detrusor. In addition, the removal of a Foley catheter increases the risk of damage to the artificial urethra. The reason for this is that the balloon, inflated for 7-10 days, is not able to collapse to its original state in the postoperative period. The overstretched balloon wall leads to an increase in the diameter of the removed catheter, which can contribute to a partial or complete rupture of the artificial urethra.

In some cases, urine leakage beyond the urethral catheter persists despite optimal drainage placement. This circumstance is usually associated with the posterior position of the bladder neck, resulting in constant irritation of the bladder wall by the catheter. In these cases, it is more effective to leave a stent in the urethra, inserted proximal to the hypospadias meatus, in combination with bladder drainage by puncture cystostomy [Fayzulin A.K. 2003].

The urethral catheter is fixed to the head of the penis at a distance (15-20 mm) for easier crossing of the ligature when removing the catheter. It is advisable to apply a duplicate interrupted suture behind the edge of the bandage and tie it with an additional knot to the urethral catheter. In this way, the urethral catheter will not pull on the head of the penis, causing pain to the patient. The outer end of the catheter is connected to a urinary receiver or is diverted into a diaper or nappies.

Usually, the urethral catheter is removed in the interval from 7 to 14 days, paying attention to the nature of the stream. In some cases, it is necessary to bougienage the artificial urethra. Since this manipulation is extremely painful, it is performed under anesthesia. After the patient is discharged from the hospital, it is necessary to conduct a control examination after 1, 2 weeks, after 1, 3 and 6 months, and then once a year until the end of penis growth, focusing the parents' attention on the nature of the stream and erection.

Wound drainage

Drainage of the postoperative wound is performed only in cases where it is impossible to apply a compression bandage to the entire area of the surgical intervention: for example, if the urethral anastomosis is applied proximal to the penoscrotal angle.

For this purpose, a thin tube No. 8 CH with multiple side holes or a rubber drain, which is brought out from the side of the skin suture line, is used. Usually, the drainage is removed the day after the operation.

Characteristics of individual methods of surgical correction of hypospadias

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MAGPI Method

The indication for the use of this technique is the location of the hypospadic meatus in the area of the coronary groove or the head of the penis without ventral deformation of the latter.

The operation begins with a bordering incision around the glans penis, 4-5 mm from the coronary groove, with the ventral surface incision being made 8 mm proximal to the hypospadic meatus.

When making an incision, it is necessary to exercise maximum caution due to the thinning of the tissue of the distal part of the urethra over which the incision is made, and the risk of the formation of a urethral fistula in the postoperative period.

The skin is incised to its full thickness down to the Buck fascia. After this, the skin of the penis is mobilised, allowing the vessels that feed the skin to be preserved. After the skin of the penis itself is incised, the superficial fascia is lifted with tweezers and dissected with vascular scissors. The tissues are bluntly separated between the superficial fascia and the Buck fascia. With proper fascia dissection, skin mobilisation occurs virtually bloodlessly.

Then, using vascular scissors, gently spread the soft tissues of the penis along the skin incision, gradually moving from the dorsal surface to the lateral sides of the penis in the interfascial space. Particular attention should be paid to manipulations in the area of the ventral surface, since it is here that the skin of the penis, the superficial fascia and the protein membrane (Buck's fascia) are intimately fused, which can lead to injury to the wall of the urethra.

The skin is removed from the shaft of the penis to the base, like a stocking, which allows for the elimination of skin torsion, which sometimes accompanies distal forms of hypospadias, and also for the creation of a mobile skin flap.

The next step is to make a longitudinal incision along the scaphoid fossa of the penis, including the dorsal wall of the hypospadias meatus, for the purpose of meatotomy, since distal forms of hypospadias are often accompanied by meatal stenosis.

The incision is made deep enough to cross the connective tissue bridge located between the hypospadic meatus and the distal edge of the navicular fossa. In this way, the surgeon achieves smoothing of the ventral surface of the glans, eliminating ventral deviation of the stream during urination.

The wound on the dorsal wall of the meatus takes on a diamond shape, which ensures the elimination of any meatal narrowing. The ventral wound is sutured with 2-3 transverse sutures using monofilament thread (PDS 7/0).

For glanuloplasty, a single-pronged hook or microsurgical tweezers are used, with the help of which the skin edge proximal to the hypospadic meatus is elevated towards the head so that the ventral edge of the surgical wound resembles an inverted V.

The lateral edges of the wound on the head are sutured with 2-3 U-shaped or interrupted sutures without tension on a urethral catheter of the age size.

When closing a wound defect with the remains of mobilized skin, there is no single method that is universal for all cases of skin grafting, since the degree of ventral skin dysplasia, the amount of plastic material on the shaft of the penis and the size of the preputial sac vary significantly. The most commonly used method of closing a skin defect is the one proposed by Smith, which involves splitting the preputial sac with a longitudinal incision along the dorsal surface. The resulting skin flaps are then wrapped around the shaft of the penis and sutured together or one under the other on the ventral surface.

In most cases, the remaining skin is sufficient to freely close the defect without any tissue movement, and the excision of the remnants of the prepuce is a mandatory step from a cosmetic point of view.

In some cases, the Tiersh-Nesbit principle is used to close the ventral wound defect, in which an opening is created in the avascular zone of the dorsal skin flap through which the glans penis is moved dorsally, and the defect on the ventral surface is covered with tissue from the fenestrated prepuce. The coronal skin edge of the wound is then sutured to the edge of this opening, and the wound on the ventral surface of the penile shaft is sutured longitudinally with a continuous suture.

Megalomeatus urethroplasty without the use of the prepuce (MIP)

The indication for the use of this technology is the coronal form of hypospadias without ventral deformation of the penile shaft, confirmed by an artificial erection test.

The principle of the operation is based on the Tiersch-Duplay technology without the use of prepuce tissue. The operation begins with a U-shaped incision along the ventral surface of the glans penis with a border of the megameatus along the proximal edge (Fig. 18-89a). Sharp scissors are used to carefully isolate the lateral walls of the future urethra without intersecting the split spongy body of the urethra. Most often, there is no need for deep isolation of the walls, since the deep scaphoid fossa allows the formation of a new urethra without the slightest tension.

The urethra is formed on a urethral catheter. The transurethral catheter should move freely in the lumen of the created channel. The optimal suture material is a monofilament absorbable thread 6/0-7/0.

In order to prevent paraurethral urine leaks in the postoperative period, a continuous precision urethral suture is used. A skin suture is applied in a similar manner.

Urethral relocation with glanuloplasty and prepuce plasty for distal hypospadias

Indications for this method are glans and coronal forms of hypospadias without signs of dysplasia of the distal urethra. At the beginning of the operation, the bladder is catheterized. The operation begins with a submeatal crescent-shaped skin incision, which is made 2-3 mm below the meatus.

This incision is extended vertically, bordering the meatus on both sides and continuing upward until they merge at the top of the glans penis. The meatus is isolated using a sharp and blunt method, then the distal urethra is mobilized. There is a fibrous layer behind the urethra. It is very important not to lose the layer during the isolation of the urethra and not to damage its wall and cavernous bodies. At this stage of the operation, special attention is paid to maintaining the integrity of the urethra and the thin skin of the penis, which helps reduce the risk of postoperative fistulas. Mobilization of the urethra is considered complete when the urethral meatus reaches the top of the glans penis without tension. To excise the remaining chord near the coronary groove, two incisions are made, each of which is about 1/4 of its circumference. After complete mobilization of the urethra, its reconstruction begins. The meatus is sutured to the top of the glans penis with an interrupted suture. The head is closed over the displaced urethra with interrupted sutures. The skin of the prepuce is given a natural appearance by transversely dissecting its ventral part on both sides and vertically connecting. Thus, the head is covered with the restored foreskin. After the operation, the penis acquires a normal appearance, the meatus is at the top of the head, the skin of the prepuce borders the head. The transurethral catheter is removed on the 7th day after the operation.

Urethroplasty method of the Mathieu type (1932)

The indication for the use of this technology is the glans form of hypospadias without deformation of the penile shaft with a well-developed scaphoid fossa, in which the urethral defect is 5-8 mm in combination with full-fledged skin of the ventral surface that does not have signs of dysplasia.

The operation is performed in one stage. Two parallel longitudinal incisions are made along the lateral edges of the navicular fossa lateral to the hypospadic meatus and proximal to the latter for the length of the urethral tube deficiency. The width of the skin flap is half the length of the circumference of the created urethra. The proximal ends of the incisions are connected to each other.

In order to reliably cover the created urethra, the spongy tissue of the glans penis is mobilized. This is a very delicate task, it is performed by careful dissection along the connective tissue bridge between the cavernous body of the glans and the cavernous bodies until the rotated flap is placed in the newly created niche, and the edges of the glans are freely closed over the formed urethra.

The proximal end of the skin flap is mobilized to the hypospadic meatus and rotated distally, applying it to the base flap so that the corners of the apex of the isolated flap coincide with the apices of the incisions on the base flap according to the flip-flap type. The flaps are sutured together with a lateral continuous intradermal precision suture from the apex of the head to the base of the flap on the urethral catheter.

The next step is to suture the mobilized edges of the glans penis with interrupted sutures over the formed urethra. Excess preputial tissue is resected at the level of the coronal groove. The operation is completed by applying a compression bandage with glycerol (glycerin). The catheter is removed on the 10th-12th day after the operation.

Tiersch-Duplay type urethroplasty method

The indication for this operation is the coronal or glans form of hypospadias in the presence of a well-developed head of the penis with a pronounced scaphoid groove.

The principle of the operation is based on the creation of a tubularized flap on the ventral surface of the penis and therefore has well-founded contraindications. This operation is undesirable to perform in patients with trunk and proximal forms of hypospadias, since the urethra created according to the Tiersch and Duplay principle is practically devoid of main feeding vessels and, accordingly, has no growth prospects. Children with proximal forms of hypospadias, operated on using this technology, suffer from the syndrome of "short urethra" in the pubertal period. In addition, the frequency of postoperative complications after using this technique is the highest.

The operation begins with a U-shaped incision along the ventral surface of the penis with a border of the hypospadic meatus along the proximal edge. Then, the edges of the wound on the glans are mobilized, penetrating along the connective tissue septum between the spongy tissue of the glans and the cavernous bodies. Then, the central flap is sutured into a tube on a No. 8-10 CH catheter with a continuous precision suture, and the edges of the glans are sutured together with interrupted sutures over the formed urethra. The operation is completed by applying a compression bandage with glycerol (glycerin).

Method of urethroplasty using buccal mucosa In 1941, G. A. Humby first proposed using buccal mucosa as a plastic material for surgical correction of hypospadias. Many surgeons used this method, but J. Duckett actively promoted the use of buccal mucosa for reconstruction of the urethra. Many surgeons avoid using this technology due to the high frequency of postoperative complications, which varies from 20 to 40%.

There are one-stage and two-stage operations in the reconstruction of the urethra using the mucous membrane of the cheek. In turn, one-stage operations are divided into three groups:

• plastic surgery of the urethra with a tubularized flap of the buccal mucosa;
• plastic surgery of the urethra using the "patch" principle;
• combined method.

In any case, the buccal mucosa is initially collected. Even in an adult, the maximum flap size that can be obtained is 55-60 x 12-15 mm. It is more convenient to collect the flap from the left cheek if the surgeon is right-handed, standing to the left of the patient. It is important to remember that the flap should be taken strictly from the middle third of the lateral surface of the cheek in order to avoid injury to the salivary gland ducts. An important condition is the distance from the corner of the mouth, since a postoperative scar can lead to deformation of the mouth line. Ranslеу (2000) for the same reason does not recommend using the mucous membrane of the lower lip for this purpose. In his opinion, a postoperative scar leads to deformation of the lower lip and impaired diction.

Before taking the flap, an injection of 1% lidok a i na or 0.5% procaine (novocaine) solution is made under the mucous membrane of the cheek. The flap is cut out sharply and the wound defect is sutured with interrupted sutures using 5/0 chromic catgut threads. Then, also sharply, the remnants of the underlying tissues are removed from the inner surface of the mucous membrane. Then the processed flap is used for its intended purpose. In cases where the urethra is formed according to the principle of a tubular flap, the latter is formed on the catheter with a continuous or interrupted suture. Then the formed urethra is sutured end to end with the hypospadiac meatus and the meatus is created, closing the edges of the dissected head over the artificial urethra.

When creating a urethra using the "patch" principle, it should be remembered that the size of the implanted mucous flap directly depends on the size of the base skin flap. In total, they should correspond to the age diameter of the formed urethra. The flaps are sutured together with a lateral continuous suture using absorbable threads 6/0-7/0 on a urethral catheter. The wound is closed with the remains of the skin of the penis shaft.

Less commonly, the buccal mucosa is used when there is a deficit of plastic material. In such situations, part of the artificial urethra is formed using one of the described methods, and the deficit of the urethral tube is eliminated using a free flap of the buccal mucosa.

Similar operations in patients with completed growth of the cavernous bodies are certainly of interest. However, with regard to pediatric urological practice, the question remains open, since it is impossible to exclude the lag in the development of the artificial urethra from the growth of the cavernous bodies of the penis. In patients with hypospadias, operated at an early age using this technology, the development of short urethra syndrome and secondary ventral deformation of the penile shaft is possible.

Urethroplasty technique using tubularized inner prepuce leaflet on a vascular pedicle

The Duckett technique is used for one-stage correction of posterior and middle forms of hypospadias depending on the reserve of plastic material (size of the foreskin). The technology is also used in severe forms of hypospadias with a pronounced skin deficiency in order to create an artificial urethra in the scrotal and scrotal-trunk sections. An important point is the creation of a proximal fragment of the urethral tube from skin devoid of hair follicles (in this case, from the inner layer of the foreskin), with the prospect of distal urethroplasty with local tissues. The determining factor is the size of the preputial sac, which limits the possibilities of plastic surgery of the artificial urethra.

The operation begins with a border incision around the glans penis, 5-7 mm from the coronal groove. The skin is mobilized to the base of the penis according to the principle described above. After mobilization of the penile skin and excision of the fibrous chord, an assessment of the true deficiency of the urethra is made. Then a transverse skin flap is cut out from the inner layer of the foreskin. An incision on the inner surface of the prepuce is made to the depth of the skin of the inner layer of the foreskin. The length of the flap depends on the size of the defect of the urethral tube and is limited by the width of the preputial sac. The flap is sutured into a tube on a catheter with a continuous precision intradermal suture using atraumatic monofilament absorbable threads. The remnants of the inner and outer layers of the foreskin are stratified in the avascular zone and are subsequently used to close the wound defect of the ventral surface of the penis. An important stage of this operation is careful mobilization of the artificial urethra from the external epithelial plate without damaging the vascular pedicle. Then the mobilized urethral tube is rotated to the venous surface to the right or left of the penis shaft depending on the location of the vascular pedicle in order to minimize the kinking of the feeding vessels. The formed urethra is sutured to the hypospadiac meatus end-to-end with a nodal or continuous suture.

The anastomosis between the artificial urethra and the glans penis is performed using the Hendren method. To do this, the epithelial layer is dissected down to the cavernous bodies, after which the distal end of the created urethra is placed in the formed cavity and sutured to the edges of the scaphoid fossa with interrupted sutures over the formed urethra. Sometimes, in children with a small glans penis, it is impossible to close the edges of the glans. In these cases, the Browne technique described in 1985 by B. Belman is used. In the classic version, tunneling of the glans penis was used to create an anastomosis of the distal section of the artificial urethra. According to the author, stenosis of the urethra occurred with a frequency of more than 20%. The use of the Hendren and Browne principle allows for a 2-3-fold decrease in the incidence of this postoperative complication. To close the cavernous bodies of the penis, previously mobilized skin of the outer layer of the prepuce is used, dissected along the dorsal surface and rotated to the ventral surface according to the Culp principle.

The method of island urethroplasty on a vascular pedicle according to the Snyder-III patch principle

This technology is used in patients with coronal and shaft forms of hypospadias (anterior and middle forms according to Barcat) without curvature of the penile shaft or with minimal curvature. Patients with pronounced curvature of the penile shaft more often require transection of the ventral skin track for complete straightening of the cavernous bodies. An attempt to straighten the penis with pronounced fibrous chord by dorsal plication leads to a significant shortening of the penile shaft length.

The operation is not indicated in patients with hypoplastic foreskin. Before the operation, it is necessary to assess the correspondence of the sizes of the inner leaflet of the prepuce and the distance from the hypospadic meatus to the apex of the glans.

The operation begins with a U-shaped incision along the ventral surface of the penis with a border of the hypospadic meatus along the proximal edge. The width of the ventral flap is formed to be no less than half the age-related length of the circumference of the urethra. Then the incision is extended to the sides, bordering the glans penis, retreating 5-7 mm from the coronal groove. Skin mobilization is performed using the method described above. The fibrous chord is excised along the sides of the ventral flap. In case of persistent curvature of the penis shaft, plication is performed along the dorsal surface.

The next step is to cut a transverse skin flap from the inner layer of the prepuce, corresponding in size to the ventral flap. The incision is made to the depth of the actual skin of the inner layer of the foreskin. Then the preputial flap is mobilized in the avascular zone, stratifying the layers of the prepuce. The skin "island" is mobilized until it moves to the ventral surface without tension. The flaps are sutured together with a continuous subcutaneous suture on a urethral catheter. First, the mesenteric edge is sutured, then the opposite one. The mobilized edges of the glans are sutured with interrupted sutures over the formed urethra. The exposed cavernous bodies are covered with the remains of the mobilized skin.

Combined method of urethroplasty using the FIII-Duplау method

Indication for surgery is the scrotal or perineal form of hypospadias (posterior according to the Barcat classification), in which the meatus is initially located on the scrotum or in the perineum at a distance of at least 15 mm proximally.

The operation begins with a border incision around the head of the penis, 5-7 mm from the coronal groove. Along the ventral surface, the incision is extended longitudinally to the penoscrotal angle. Then, the skin of the penis is mobilized to the transition to the scrotum along the ventral surface. Along the dorsal and lateral surfaces, the skin is mobilized to the penosyphyseal space with dissection of the lig. suspensorium penis.

At the next stage, urethroplasty is performed using the F III technology, and the gap from the hypospadic meatus to the penoscrotal angle is performed using the Duplay method. N. Hodgson suggests suturing fragments of the artificial urethra end to end on a No. 8 CH urethral catheter. It is known that the number of postoperative complications when using end anastomoses reaches 15-35%. In order to minimize complications, the onlay-tube or onlay-tube-onlay principle described below is currently used. The wound defect is sutured with a continuous twisting suture. The operation is traditionally completed by applying a dressing with glycerol (glycerin).

The combined principle of urethroplasty for proximal forms of hypospadias may also consist of an island tubularized skin flap from the inner layer of the foreskin (Duckett principle) and the Duplay method, as well as the Asopa technology in combination with the Duplay method.

[ 31 ], [ 32 ], [ 33 ], [ 34 ]

Urethroplasty method F-II

This method of surgical correction of hypospadias is based on the principle developed by N. Hodgson (1969-1971). But in essence it is a modification of a known method. It is used for anterior and middle forms of hypospadias.

In 50% of patients with distal hypospadias, congenital meatus stenosis is diagnosed. Surgery begins with a bilateral lateral meatotomy according to Duckett. The length of the incisions varies from 1 to 3 mm, depending on the patient's age and the severity of the stenosis. The incision line is preliminarily crushed with a mosquito-type hemostatic clamp, and after dissection of the meatus, a nodal suture is applied to the incision area, but only if blood leakage from the edges of the wound is noted. After eliminating the meatus stenosis, the main stage of the surgical intervention begins.

A U-shaped incision is made on the ventral surface of the penis with a border of the meatus along the proximal edge. In the classic version, the width of the base flap is made equal to half the length of the circumference of the urethra. A modified incision on the ventral surface is made along the edge of the scaphoid fossa, which does not always correspond to half the length of the circumference of the urethra. Most often, the shape of this incision resembles a vase with a widened neck, a narrowed neck and a widened base.

In these cases, the opposite flap is formed in such a way that when the flaps are applied, a perfectly even tube is obtained. In those places where an expansion was formed on the base flap, a narrowing is created on the donor flap, and vice versa.

A shaped incision on the ventral surface is made in order to maximally preserve the glans tissue for the final stage of glanuloplasty and to provide more convenient access to the connective tissue intercavernous groove separating the spongy tissue of the glans penis and the cavernous bodies.

Penile skin mobilization is performed using standard technology up to the penoscrotal angle. In cases where the deep dorsal vein of the penis has a perforating vessel connected to the skin flap, surgeons try not to cross it. Maximum preservation of the venous angioarchitectonics of the penis helps to reduce venous stasis and, accordingly, decrease the degree of penile edema in the postoperative period. For this purpose, the perforating vessel is mobilized up to the level where the dorsal flap is laid freely, without the slightest tension after moving the skin flap to the ventral surface. In cases where flap mobilization is impossible due to vessel tension, the vein is ligated and dissected between the ligatures without coagulation. Coagulation of the perforating vessel can lead to thrombosis of the main venous trunks.

The preputial flap for forming the urethra is cut to the thickness of the skin of the outer layer of the foreskin. Only the skin is cut without damaging the subcutaneous tissues rich in vessels that feed the preputial flap.

The penis shaft is moved using the Tiersch-Nesbit technique. Given the presence of meatotomy incisions, it became necessary to modify the principle of suturing the skin flaps. In this case, the basic nodal suture is applied at 3 o'clock from the right edge of the meatus, and then, during suturing of the urethral flaps, the dorsal flap is sutured to the tunica albuginea in close proximity to the ventral edge. This technique allows for the creation of a hermetic line of the urethral suture without technical difficulties and avoidance of urinary leaks.

According to the method proposed by N. Hodgson, the ventral surface of the glans penis remains made of prepuce skin, which creates an obvious cosmetic defect with a good functional result. Later, when the patient enters into sexual life, such a type of glans causes tactless questions and even complaints from sexual partners, which, in turn, sometimes leads to nervous breakdowns and the development of an inferiority complex in the patient who has undergone surgery.

In the modification of the final stage of this operation (F-II) a variant of the solution of this problem is offered. The essence lies in de-epithelialization of the distal section of the artificial urethra using microsurgical scissors and suturing the edges of the head of the penis over the formed urethra, this technique allows to imitate the natural appearance of the head of the penis.

For this purpose, the epidermis is excised with microsurgical scissors curved along the plane without capturing the underlying tissues in order to preserve the vessels of the skin flap, retreating 1-2 mm from the artificial meatus, meepithelialization is performed to the projection level of the coronal groove. Then the lateral edges of the wound on the head of the penis are sutured together over the created urethra with interrupted sutures without tensioning the skin tissue, thus, it is possible to close the ventral surface of the head of the penis, which allows the appearance of the head of the penis to be brought as close as possible to the physiological state. The final stage of the operation is no different from the standard method described above.

Method of urethroplasty for hypospadias without hypospadias type IV (F-IV, FV)

One of the options for correcting hypospadias without type IV hypospadias is the technology of replacing a fragment of the dysplastic urethra based on the operations of the N. Hodgson (F-IV) and Ducken (F-V) types. The principle of the operation is to preserve the head part of the urethra and replace the dysplastic fragment of the trunk part of the urethra with an insertion of skin from the dorsal surface of the penis or the inner leaflet of the prepuce on a pedicle with a double urethral anastomosis of the onlay-tube-onlay type.

The F-IV operation begins with a border incision around the glans penis. The skin on the ventral surface in hypospadias without hypospadias is often unchanged, so a longitudinal incision along the ventral surface is not made. The skin is removed from the penis like a stocking to the base of the shaft. Excision of the superficial fibrous strands is performed. Then, resection of the dysplastic urethral tube, devoid of the corpus cavernosum, is performed from the coronary groove to the beginning of the corpus spongiosum of the urethra. In some cases, the fibrous chord is located between the dysplastic urethra and the cavernous bodies. The chord is excised without any particular problems due to wide access. The degree of straightening of the penile shaft is determined using an artificial erection test.

The next step is to cut out a rectangular skin flap on the dorsal surface of the skin flap, the length of which corresponds to the size of the urethral defect, and the width to the length of the circumference of the urethra, taking into account the patient's age.

Then, two openings are formed in the proximal and distal sections of the created flap for further movement of the penis shaft. The epithelial flap is sutured on the catheter with a continuous suture, retreating 4-5 mm from the ends of the flap. This technique allows increasing the cross-sectional area of the terminal anastomoses and, accordingly, reducing the frequency of urethral stenosis, since the experience of surgical treatment of hypospadias has shown that in almost all cases, narrowing of the urethra occurs precisely in the area of the terminal joints.

The penis is then moved twice along the Nesbit: first through the proximal opening to the dorsal surface, and then through the distal opening to the ventral side. The latter movement is preceded by the creation of an onlay-tube anastomosis between the proximal end of the artificial urethra and the hypospadic meatus. After the second movement of the penile shaft through the distal opening, a distal anastomosis is created between the efferent end of the new urethra and the afferent end of the glans section of the proper urethra using the tube-onlay principle similar to the first. Urethral anastomoses are created using a No. 8-10 CH urethral catheter.

To close the skin defect on the dorsal surface of the penis, gentle mobilization of the lateral edges of the dorsal flap wound is performed. After that, the wound is closed by suturing the edges together with a continuous suture. The remaining skin around the glans is also continuously sutured with the distal edge of the mobilized flap. The defect on the ventral surface of the penis is closed with a longitudinal intradermal suture. When performing urethroplasty, it is necessary to avoid the slightest tension of the tissue, which leads to marginal necrosis and divergence of the suture line.

A modified Duckett (FV) procedure can also be used to correct hypospadias without hypospadias in combination with urethral dysplasia.

The determining factor for performing this operation is the presence of a well-developed foreskin, with the width of the inner leaflet sufficient to create the missing fragment of the urethra. The distinctive feature of this operation in comparison with the classical Duckett operation is the preservation of the glans section of the urethra with a double urethral anastomosis of the onlay-tube-onlay type after creating an artificial urethra from the inner leaflet of the prepuce and moving it to the ventral surface of the penis. The skin defect is closed according to the principle described above.

Urethroplasty technique using a lateral flap (F-VI)

This is a modification of the Broadbent operation (1959-1960). The fundamental difference of this technology is the total mobilization of the cavernous bodies in patients with posterior hypospadias. The method also involves dividing the skin flap used to create an artificial urethra with a hypospadic meatus. The Broadbent technology used a urethral anastomosis according to the Duplay principle, and in a modified version according to the end-to-end principle, onlay-tube or onlay-tube-onlay.

The operation begins with a bordering incision around the head of the penis. The incision is then extended along the ventral surface to the hypospadic meatus with a border of the latter, retreating 3-4 mm from the edge. After mobilizing the skin of the penis to the base of the trunk with the intersection of lig. suspensorium penis, excision of the fibrous chord is performed.

Having assessed the true deficiency of the urethra after straightening the penis, it is obvious that it usually significantly exceeds the reserve of plastic material of the penis shaft itself. Therefore, to create an artificial urethra, one of the edges of the skin wound, which has minimal signs of ischemia, is used along its entire length. For this, four holders are applied in the supposed area of the flap creation. corresponding in length to the deficiency of the urethra. Then, the borders of the flap are marked with a marker and incisions are made along the designated contours. The depth of the incision along the side wall should not exceed the thickness of the skin itself, in order to preserve the vascular pedicle. The shape of the flap is created using the onlay-tube-onlay technology described above.

A particularly important point is the isolation of the vascular pedicle, since the thickness of the full-layer flap does not always allow this manipulation to be performed easily. On the other hand, the length of the vascular pedicle should be sufficient for free rotation of the new urethra to the ventral surface with the urethral suture line directed towards the cavernous bodies. The artificial urethra is formed according to the onlay-tube-onlay principle. After moving the urethra to the ventral surface, axial rotation of the penis shaft by 30-45* sometimes occurs, which is eliminated by rotating the skin flap in the opposite direction. The operation is completed by applying a compression bandage with glycerol (glycerin).

[ 35 ], [ 36 ], [ 37 ], [ 38 ], [ 39 ]

Hypospadias correction method based on the onlay-tube-onlay and onlay-tube principle (F-VllI, F IX)

Stenosis of the urethra is one of the most serious complications that arise after its plastic surgery in posterior and middle forms of hypospadias. Bougienage of the urethra and endoscopic dissection of the narrowed section of the urethra often lead to relapse of stenosis and, ultimately, to repeated surgery.

Stenosis of the urethra usually forms in the area of the proximal urethral anastomosis, imposed on the principle of end-to-end. In the process of searching for a rational method of correction of the defect, a method was developed that allows to avoid the use of end anastomosis, called onlay-tube-onlay.

The operation begins with a shaped incision. To do this, a flap resembling the letter U is cut out along the ventral surface of the glans penis. The width of the flap is formed according to the age diameter of the urethra, it is half the length of the circumference of the urethra. Then the incision is extended along the midline of the ventral surface of the trunk from the base of the U-shaped incision to the hypospadiac meatus. retreating h = 5-7 mm from its distal edge. Around the meatus, a skin flap is cut out, facing the angle in the distal direction. The width of the flap is also half the length of the circumference of the urethra. The next step is to make a bordering incision around the glans penis until the incision lines merge on the ventral surface.

The skin of the penis shaft is mobilized according to the principle described above. Then the fibrous chord is excised until the cavernous bodies are completely straightened. After which they begin to create an artificial urethra.

On the dorsal surface of the skin flap, a shaped island is cut out, resembling a two-handed rolling pin. The length of the entire dorsal flap is formed depending on the deficiency of the urethral tube. The proximal narrow fragment of the flap should correspond in width and length to the proximal skin island of the ventral surface, and the distal narrow fragment of mobilized skin is created similar to the distal one on the shaft of the penis. The fundamental moment in the process of forming flaps remains the exact ratio of the incision angles. It is the spatial understanding of the configuration of the future urethra that allows you to avoid stenosis in the postoperative period.

The skin island formed on the dorsal skin flap is mobilized using two microsurgical tweezers. Then, a window is created at the base of the flap using a blunt method, through which the exposed cavernous bodies are transferred dorsally. The proximal narrow dorsal fragment is sutured to the proximal ventral one using the onlay principle with a continuous intradermal suture to the point indicated in the figure by number 3. The starting points on the dorsal and ventral flaps must coincide. The main fragment of the artificial urethra is also sutured into a tube continuously. The distal section is formed similarly to the proximal one in a mirror image. The urethra is created on a No. 8 CH urethral catheter.

The onlay-tube-onlay principle is used when the glans penis is underdeveloped and the surgeon has doubts at the stage of its closure. In patients with a well-developed glans, the onlay-tube principle is used (Fig. 18-96).

To do this, one skin island is cut out on the ventral surface, bordering the meatus according to the principle described above. On the dorsal surface, a flap is created that resembles a one-handed rolling pin, the handle facing the base of the penis shaft. After creating the urethral tube, the distal section of the artificial urethra is deepithelialized just enough to close the mobilized edges of the head over the urethra. The edges of the head are sutured together with interrupted sutures over the created urethra. The exposed cavernous bodies are covered with mobilized skin of the penis.

Method of urethroplasty in children with posterior hypospadias using the urogenital sinus (F-VII)

Urogenital sinus is often detected in children with severe forms of hypospadias. Normally, during the formation of the genitals, the sinus is transformed into the prostate and posterior urethra. However, in 30% of patients with severe forms of hypospadias, the sinus is preserved. The size of the sinus is variable and can fluctuate from 1 to 13 cm, and the higher the degree of violation of sexual differentiation, the larger the sinus. Almost all patients with a pronounced sinus have no prostate, and the vas deferens are either completely obliterated or open into the sinus. The internal lining of the urogenital sinus is usually represented by urothelium, adapted to the effects of urine. Given this circumstance, the idea arose to use the tissue of the urogenital sinus for plastic surgery of the urethra.

This idea was first put into practice in a patient with true hermaphroditism with a 46 XY karyotype and virile genitals.

During clinical examination, the child was diagnosed with perineal hypospadias, the presence of a gonad in the scrotum on the right and a gonad in the inguinal canal on the left. During surgery, during revision of the inguinal canal on the left, an ovotestis was detected, confirmed histologically, i.e. a mixed gonad with female and male germ cells. The mixed gonad was removed. The urogenital sinus was isolated, mobilized and rotated distally.

The sinus was then modeled into a tube using the Mustarde principle up to the penoscrotal angle. The distal part of the artificial urethra was formed using the Hodgson-III method.

Tissue-engineered urethral plastic surgery (FVX)

The need to use plastic material devoid of hair follicles is dictated by the high frequency of remote postoperative complications. Hair growth in the urethra and the formation of stones in the lumen of the created urethra create significant problems for the patient's life and great difficulties for the plastic surgeon.

Currently, technologies based on the achievements of tissue engineering are becoming increasingly widespread in the field of plastic surgery. Based on the principles of treating burn patients using allogeneic keratinocytes and fibroblasts, the idea of using autologous skin cells for hypospadias correction arose.

For this purpose, a skin sample of 1-3 cm2 is taken from the patient in a hidden area, immersed in a preservative, and delivered to a biological laboratory.

Human keratinocytes are used in the work, since epithelial-mesenchymal relationships are not species-specific (Cunha et al., 1983: Hatten et al., 1983). Skin flaps measuring 1x2 cm are placed in Eagle's medium containing gentamicin (0.16 mg/ml) or 2000 U/ml benzylpenicillin and 1 mg/ml streptomycin. The prepared skin flaps are cut into strips measuring 3x10 mm. washed in a buffer solution, placed in a 0.125% dispase solution in DMEM medium and incubated at 4 °C for 16-20 h or in a 2% dispase solution for 1 h at 37 °C. After this, the epidermis is separated from the dermis along the basement membrane line. The suspension of epidermal keratinocytes obtained by pipetting is filtered through a nylon mesh and precipitated by centrifugation at 800 rpm for 10 min. The supernatant is then drained and the sediment is suspended in a culture medium and seeded in plastic flasks (Costaf) at a concentration of 200 thousand cells/ml of medium. Then, keratinocytes are grown for 3 days in a complete nutrient medium: DMEM: F12 (2:1) with 10% fetal calf serum, 5 μg/ml soluble insulin (human genetically engineered), 10"6 M isoproterenol*3, 5 μg/ml transferrin. Then the cells are grown in DMEM:F12 (2:1) medium with 5% blood serum, 10 ng/ml epidermal growth factor, insulin and transferrin and the medium is changed regularly. After the cells form a multilayer layer, differentiated suprabasal keratinocytes are removed, for which the culture is incubated for three days in DMEM medium without Ca. After this, the keratinocyte culture is transferred to a complete medium and, after 24 hours, passaged onto the surface of a living tissue equivalent formed by fibroblasts enclosed in a collagen gel.

Preparation of living tissue equivalent

The mesenchymal base of the transplant, collagen gel with fibroblasts, is prepared as described above and poured into Petri dishes with a Spongostan sponge. The final polymerization of the gel with the sponge and fibroblasts enclosed inside occurs at 37 °C for 30 minutes in a CO2 incubator. The following day, epidermal keratinocytes are planted on the surface of the dermal equivalent at a concentration of 250 thousand cells/ml and cultured for 3-4 days in a CO2 incubator in a complete medium. The day before transplantation, the living equivalent is transferred to a complete medium without serum.

As a result, after several weeks, a three-dimensional cellular structure is obtained on a biodegradable matrix. The dermal equivalent is delivered to the clinic and formed into the urethra, stitched into a tube or using the onlay principle for urethroplasty. Most often, this technology is used to replace the perineal and scrotal sections of the artificial urethra, where the threat of hair growth is greatest. The urethral catheter is removed on the 10th day. After 3-6 months, distal urethroplasty is performed using one of the above methods.

When evaluating the results of surgical treatment of hypospadias, it is necessary to pay attention to the functional and cosmetic aspects that allow minimizing the psychological trauma of the patient and optimally adapting him to society.

Prevention

Prevention of this disease should be considered the exclusion of drugs, external environmental factors and food products that interfere with the normal development of the fetus and are called in the literature by the term "disruptors". Disruptors are chemical compounds that disrupt the normal hormonal status of the body.

These include all types of hormones that block the synthesis or replace the body's own hormones, for example, when there is a risk of miscarriage, gynecologists often use hormonal therapy - usually hormones of the female body, which, in turn, block the synthesis of male hormones responsible for the formation of the genitals. Disruptors also include non-hormonal chemical compounds that enter the body of a pregnant woman with food (vegetables and fruits treated with insecticides, fungicides).

[ 40 ], [ 41 ], [ 42 ], [ 43 ]