Retinal detachment: treatment

Surgical treatment of retinal detachment aims to block retinal ruptures and eliminate vitreoretinal fusion, which retracts the retina into the vitreous cavity.

All the methods of surgical interventions used can be divided into three groups.

Hyper- or hypothermic (photocoagulation, diathermocoagulation, cryopexy), local transpupillary or transscleral effects, designed to cause adhesive inflammation in the retinal rupture site and firmly fix the retina.

Scleroplastic operations (temporary ballooning or permanent local, circular or combined filling of the sclera in the area of the projection of rupture of the retina by silicone or biological implants), aimed at restoring the contact of the retina with the underlying membranes. A seal applied externally to the sclera pushes it inward and brings the outer capsule of the eye and the choroid to the detached and shortened retina.

Intravitreal operations are operations that are performed inside the cavity of the eye. First of all vitrectomy is performed - excision of the altered vitreous body and vitreoretinal schwarzes. Expanding gases, perfluoroorganic compounds or silicone oil are used to press the retina to the underlying shells of the eye. Retinotomy is the dissection of a shortened and contracted detached retina, followed by its spreading and fixation of the edges with the help of cryo- or endolaser coagulation. In some cases, microscopic retinal nails and magnets are used. All these operations are performed with endoscopic illumination with the help of special manipulators.

A prerequisite for the success of surgery for retinal detachment is their timeliness, since the prolonged existence of retinal detachment leads to death of the optic-neural elements of the retina. In such cases, even with complete anatomical fit of the retina, there is no restoration or enhancement of visual functions. A constant careful ophthalmoscopic control is also necessary to ensure a reliable blockade of all retinal ruptures during the operation. In the absence of contact of the retina with the underlying shells in the rupture zone, external or internal evacuation of the subretinal fluid and a combination of both episcleral and endovitral techniques are indicated.

When performing the operation at a modern technical level, it is possible to achieve a retina fit in 92-97% of patients. In the early postoperative period, local and general anti-inflammatory therapy with non-steroidal and steroid drugs, systemic enzyme therapy in the presence of hemorrhages is indicated. In the future, it is advisable to conduct repeated courses of treatment, including drugs that normalize hemodynamics and microcirculation of the eye. Patients operated on for retinal detachment should be under the supervision of an ophthalmologist and avoid physical overload

Vision forecast

The main factor responsible for the final visual functions after a successful retina is the duration of the involvement of the macula.

• In most cases, detachment of the retina with the involvement of the macula preserves the additional visual acuity.
• Delayed surgical intervention for a week with retinal detachment without involvement of the macula does not affect the restoration of vision in the future.
• With detachment of the retina without involvement of the macula with a duration of less than 2 months, some deterioration in visual acuity occurs, but there is no direct correlation between the duration of macular detachment and the final visual acuity.
• With detachment of the retina without involvement of the macula with a duration of more than 2 months, a significant visual impairment occurs, which is most likely due to the duration of involvement of the macular zone.

Principles of scleral filling

The filling of the sclera consists in creating a scleral depression inside. The explant is a material sewn directly onto the sclera. The main goal is to close the retinal rupture by connecting the PES with a sensory retina; reduction of dynamic vitreoretinal traction in the local area of vitreoretinal adhesions.

Local explants

Configuration

• Radial explants are placed at right angles to the limb;
• circular explants are placed parallel to the limb with the creation of a sectoral shaft.

Dimensions. To adequately close the retinal rupture, it is important that the shaft has an exact position, the correct length, width and height.

• a) the width of the radial shaft depends on the width of the retinal rupture (the distance between its front ends), and the length - from the length of the rupture (the distance between its base and apex). Usually the shaft size is 2 times the size of the rupture. The required width and length of the sectoral circular shaft depends on the length and width of the gap, respectively;
• b) the height is determined by the following interrelated factors:
  • The larger the diameter of the explant, the higher the shaft.
  • The further the seams are located, the higher the shaft.
  • The tighter the joints are tied, the higher the shaft.
  • The lower the intraocular pressure, the higher the shaft.

Indications for radial sealing

• Extensive U-shaped breaks, in which the probability of the "fish mouth" effect is small.
• Relatively rear tears for easier suturing.

Indications for sectoral circular sealing

• Multiple discontinuities localized in one or two quadrants.
• Front gaps that are easier to close.
• Wide breaks in the type of dialysis.

Cirkular Explants

Dimensions. More often use a tape with a width of 2 mm (No. 40). The cirque tape creates a rather narrow shaft, so it is often supplemented with radial sponges or circular strong silicone rims to close large gaps. A shaft 2 mm high can be achieved by pulling the seal up to 12 mm. The shaft created by zirklyazhpymi fillings (in contrast to local), is kept constantly.

Indications

• Gaps that include three or more quadrants.
• Degeneration by the type of "lattice" or "trail of a cochlea" with the inclusion of three or more quadrants.
• A common detachment of the retina without visible ruptures, especially with turbidity of media.
• After unsuccessful local interventions, in which the cause of the failure remained unclear.

Scleral sealing technique

Preliminary preparation

1. Using conjunctival scissors, a circular incision of the conjunctiva with a stenon capsule is made around the limb in quadrants corresponding to retinal ruptures.
2. The tenotomic hook is inserted under the corresponding straight muscles, followed by overlapping of the sutures.
3. The sclera is examined to detect areas of thinning or an anomaly of the vorticoid veins, which may be important for subsequent suturing and drainage of the subretinal fluid.
4. The scleral suture of the 5/0 dacron is superimposed on the area calculated according to the tip of the rupture.
5. The tip of the seam is caught with a curved tweezers like "mosquito" as close as possible to the knot.
6. With indirect ophthalmoscopy, tweezers compress the scissors. If the impression does not coincide with the rupture, the procedure is repeated until accurate localization is achieved.
7. With the help of the cryoconductor, sclerokompression is performed carefully followed by cryorexia until a pitting area (2 mm) around the rupture is formed.

Lapping of the local explant

1. According to the criteria listed above, an explant of the appropriate size is chosen.
2. With the help of a circular meter, the places of application of seams are determined, which are marked on the sclera by a thermocouter.

NB: As a rule, the distance between the seams should be 1.5 times the explant diameter.

3. The explant is hemmed in by applying a "mattress" seam.
4. If necessary, draining the subretinal fluid.
5. Check the position of the rupture with respect to the shaft and, if necessary, produce a shaft reposition.
6. Stitches are tightened over the explant.

Technique of drainage-air-cryo explant

The localization relative to anterior gaps with a low level of subretinal fluid is simple. With bullous detachment of the retina, precise localization is rather difficult, especially if the gaps are located postequatorially. In such cases, this technique is the most suitable.

1. The subretinal fluid is drained to create a contact between the retina (and hence the rupture) and PES.
2. In the vitreous cavity, air is introduced to prevent hypotension caused by drainage.
3. After this, the rupture can be accurately localized with subsequent cryocoagulation.
4. Explant is introduced.

Cirkulation procedure

1. Select the tape of the desired diameter.
2. One end of the tape is seized with a curved forceps type "mosquito" and is injected under four straight muscles.
3. The ends of the tape are inserted into the sleeve of the Watzke, respectively, to the original quadrant.
4. The tape is tightened by pulling the ends so that it gently lies around the area of the "dentate" line.
5. The tape is gradually moved backwards (about 4 mm) and strengthened with the help of supporting seams in each quadrant.
6. The subretinal fluid is drained.
7. The tape is tightened to achieve the required height of the impression shaft and control of indirect ophthalmoscopy.

NB: The ideal height is 2 mm. This can be achieved by reducing the circumference of the tape to 12 mm.

8. The circular impression shaft is created so that the retinal breaks "lie" on the front surface of the shaft (i.e., the shaft should be directly behind the rupture).
9. If necessary, a radial sponge can be inserted under the tape to block an extensive U-shaped rupture or a cirque tape to block several tears; It must be ensured that the shaft covers the base of the vitreous in front.

Draining of subretinal fluid

Drainage of the subretinal fluid provides immediate contact between the sensory retina and the PES. In the treatment of most retinal detachment, drainage can be avoided, but under certain circumstances, drainage is necessary. However, it may be associated with potential complications (see below). If drainage is not done, these complications can be avoided, but then most often, immediate contact between the sensory retina and the PES with the flattening of the macular zone is not achieved. If the contact is not reached within 5 days, then a satisfactory shaft around the rupture does not develop due to a decrease in the density of the PES. This leads to non-retention of the retina, and in some cases to a secondary "opening" of the gap in the postoperative period. In addition, draining the subretinal fluid allows the use of internal tamponade (air or gas), which form a large bubble.

Indications

• Difficulties in the localization of ruptures with bullous fluid detachment, especially in cases of equatorial rupture.
• Stillness of the retina (for example, PVR), since a successful operation without drainage is possible with sufficient mobility of the detached retina for its further adherence in the postoperative period.
• Old retinal detachment, when the subretinal fluid is viscous and it may take months to resolve it, so drainage is necessary, even if the rupture can be blocked without it.
• The lower detachment of the retina with the accompanying equatorial ruptures should be carefully drained. Since with the vertical position of the patient in the postoperative period, the residuals of the subretinal fluid can move downward and provoke a secondary rupture.

The drainage technique does not have any standards. Two more popular methods are described below.

Method A

• Reduction of external pressure on the eyeball due to weakening of traction joints and lifting of the eyelid.
• Radial sclerotomy 4 mm long exactly above the area of the highest subretinal fluid level; a choroid is inserted into the incision.
• The inserted choroid is perforated along the tangential line using a hypodermic needle on a syringe or a surgical needle on the needle holder

Method B

• Perforation is performed by a single, rapid, controlled movement directly through the sclera, choroid and PES with a hypodermic needle, keeping it at an angle 2 mm from the tip.
• To prevent hemorrhage in the drainage area, external finger compression is performed on the eyeball until the occlusion of the central artery and complete blanching of the choroidal vascular network.
• Compression is carried out for 5 minutes, then the examination of the fundus is performed; with continuing bleeding, the compression is repeated for another 2 minutes.

Complications

• Hemorrhages associated usually with the perforation of a large choroidal vessel.
• Unsuccessful drainage (for example, the dry tip of the needle) can be caused by the pinching of intraocular structures in the slit.
• Iatrogenic rupture caused by retinal perforation during drainage.
• Infringement of a retina is a serious complication at which further actions can appear unsuccessful,
• The effect of "fish mouth" is typical for U-shaped gaps with its paradoxical expansion after scleral depression and draining of the subretinal fluid. The rupture can communicate with the radial fold of the retina, which complicates its blocking. Tactics in this case consists in creating an additional radial shaft and introducing air into the vitreal cavity.

[1], [2], [3], [4], [5], [6], [7], [8],

Intravitreal injection of air

Indications

• Acute hypotension after draining the subretinal fluid.
• Effect of "fish mouth" with U-shaped rupture.
• Radial folds of the retina.

Equipment

• use filtered air of 5 ml in a syringe with a needle;
• the eyeball is fixed, then the needle is inserted at a distance of 3.5 mm from the limb through the flat part of the ciliary body;
• with simultaneous indirect ophthalmoscopy without a condenser lens, the needle is directed to the center of the vitreal cavity with further movement until it becomes subtle in the pupil area;
• gently produce a single injection.

Potential complications

• Loss of visualization of the fundus caused by the formation of small air bubbles with an excessively deep introduction of the needle into the vitreal cavity.
• Increase in intraocular pressure in excess of the introduced volume of air.
• Damage to the lens with a needle, if it was directed anteriorly.
• Damage to the retina in the case of an excessive needle backward,

Pneumatic retinopexy

Pneumatic retinopexy is an outpatient operation in which an expanding gas bubble is intravitreal introduced to block the retinal rupture and the retina without a scleral filling. The most commonly used sulfur hexafluoride and perfluoropropane.

The indications are uncomplicated retinal detachments with small retinal ruptures or a group of ruptures within two hour meridians located at 2/3 of the upper periphery of the retina.

Technique of operation

• gaps are blocked by cryocoagulation;
• intravitreally administered 0.5 ml of 100% SF ₆ or 0.3 ml of 100% perfluoropropane;
• after surgery, the patient assumes such a position that the rising gas bubble is in contact with the rupture located on top for 5-7 days;
• if necessary, cryo-or lasercoagulation around the rupture can be performed.

Retinal detachment - Errors in operation

Errors in the early stages

Most often, they are associated with the presence of an unlocked gap due to errors committed before or after the operation.

Preoperative causes. About 50% of all retinal detachments are accompanied by several discontinuities, which in most cases are located under 90 relative to each other. In this regard, the surgeon needs to perform a detailed examination to identify all possible ruptures and determine the primary rupture, respectively, the configuration of retinal detachment. If the medium is clouding or the IOL is present, the inspection of the periphery is difficult, which makes it impossible to detect retinal ruptures.

NB: If there are no ruptures at the periphery, then as the last option of choice it is possible to assume the presence of a rupture in the posterior pole, for example a true rupture of the macula.

Reasons for the operation

• Inadequate dimensions of the created shaft of the impression, its incorrect height, erroneous position or a combination of these factors.
• The effect of "fish mouth" with a rupture of the retina, which can be caused by a communicable retinal fold.
• Loss of iatrogenic rupture caused by reckless drainage of subretinal fluid.

Errors in the later stages

Relapse of detachment of the retina after a successful operation can be caused by the following reasons.

PVR is the most common cause. The evaluation of the incidence of ATS varies from 5 to 10% and depends on the characteristics in each individual case and clinical risk factors (aphakia, preoperative TAC, extensive retinal detachment, anterior uveitis and excessive dose of cryotherapy). The traction force associated with the TAC can lead to recurrence of old gaps and the appearance of new ones. Usually it develops between 4 and 6 weeks after the operation. After a successful retina adhesion and an initial period of improvement in visual function, the patient has a sudden and progressive deterioration in vision, which can develop within a few hours.

NB: The possibility of postoperative PVR may be reduced in patients at risk by additional intravitreal administration of a solution of 5-fluorouracil and low-molecular-weight heparin during vitrectomy.

1. The recurrence of the old retinal rupture without PTA can develop as a result of inadequate chorioretinal response or late complications associated with the filling.
2. New gaps may appear in those parts of the retina that are prone to permanent vitreoretinal traction after local sealing.

Complications after surgery

Associated with explant

• Local infection can develop at any time and provoke rejection of the filling, and in rare cases - lead to cellulite orbit.
• Seizure rejection may develop several weeks or months after surgery. Its removal in the first few months after surgery is associated with a risk of relapse of retinal detachment in 5-10% of cases.
• Erosion through the skin is very rare.

Maculopotomy

• "Cellophane" maculopathy is characterized by a pathological reflex from the macula and is not associated with changes in the paramacular vessels. In this case, normal visual acuity can be maintained.
• Macular folds are characterized by the presence of a cloudy epiretinal membrane with changes in blood vessels. This complication does not depend on the type, size and duration of retinal detachment or type of surgical intervention. In most cases, visual acuity is not higher than 6/18.
• Pigmented maculopathy is most often the result of an excessive dose of cryocoagulation.
• Atrophic maculopathy usually appears due to the leakage of blood into the subretinal space, caused by hemorrhagia from the choroid during surgery. Observe in operations with drainage of subretinal fluid, in which passage of the needle allows the blood to enter the subretinal space.

Diplopia

Transient diplopia often occurs immediately in the postoperative period and is a favorable prognostic sign, indicative of the contiguity of the macular area. Permanent diplopia is rare, and there may be a need for surgery but its correction or injection of CI toxin. Bolnlinum. The main factors predisposing to diplopia are:

• The large size of a seal inserted under a straight muscle. In most cases, diplopia passes independently in a few weeks or months and does not require special treatment, except for the possible use of temporary prismatic glasses. Very rarely, it may be necessary to remove the sponge.
• Detachment of the rectus muscle during surgery (usually the upper or lower) when trying to insert a seal under it.
• The rupture of the muscular abdomen as a result of excessive stretching of the bridle sutures.
• Coarse scars of the conjunctiva, usually associated with repeated operations, mechanically limit eye movements.
• Decompensation of a significant heterophory, which is a consequence of poor postoperative visual acuity of the operated eye.

[9], [10], [11]