Developmental anomalies of the lens

Anomalies in the development of the lens can have different manifestations. Any changes in the shape, size and localization of the lens cause significant impairments of its function.

Congenital aphakia - absence of the lens - is rare and is usually combined with other eye developmental defects.

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Symptoms of lens developmental anomalies

Microphakia - a small lens. Usually this pathology is combined with a change in the shape of the lens - spherophakia (spherical lens) or a violation of the hydrodynamics of the eye. Clinically, this is manifested by high myopia with incomplete vision correction. A small round lens, suspended on long weak threads of the circular ligament, has significantly greater than normal mobility. It can insert into the lumen of the pupil and cause a pupillary block with a sharp increase in intraocular pressure and pain syndrome. To release the lens, it is necessary to dilate the pupil with medication.

Microphakia in combination with subluxation of the lens is one of the manifestations of Marfan syndrome, a hereditary malformation of the entire connective tissue. Ectopia of the lens, a change in its shape, is caused by hypoplasia of the ligaments that support it. With age, the rupture of the Zinn ligament increases. At this point, the vitreous body protrudes as a hernia. The equator of the lens becomes visible in the pupil area. Complete dislocation of the lens is also possible. In addition to eye pathology, Marfan syndrome is characterized by damage to the musculoskeletal system and internal organs.

It is impossible not to pay attention to the peculiarities of the patient's appearance: tall stature, disproportionately long limbs, thin, long fingers (arachnodactyly), poorly developed muscles and subcutaneous fat, curvature of the spine. Long and thin ribs form an unusually shaped chest. In addition, malformations of the cardiovascular system, vegetative-vascular disorders, dysfunction of the adrenal cortex, and disturbance of the daily rhythm of glucocorticoid excretion with urine are revealed.

Microspherophakia with subluxation or complete dislocation of the lens is also observed in Marchesani syndrome - a systemic hereditary lesion of mesenchymal tissue. Patients with this syndrome, unlike patients with Marfan syndrome, have a completely different appearance: short stature, short arms that are difficult for them to grasp their own head, short and thick fingers (brachydactyly), hypertrophied muscles, an asymmetrical compressed skull.

Coloboma of the lens is a defect of the lens tissue along the midline in the lower section. This pathology is extremely rare and is usually combined with coloboma of the iris, ciliary body and choroid. Such defects are formed due to incomplete closure of the embryonic fissure during the formation of the secondary optic cup.

Lenticonus is a cone-shaped protrusion of one of the surfaces of the lens. Another type of lens surface pathology is lentiglobus: the anterior or posterior surface of the lens has a spherical shape. Each of these developmental anomalies is usually noted in one eye and may be combined with opacities in the lens. Clinically, lenticonus and lentiglobus are manifested by increased refraction of the eye, i.e. the development of high myopia and difficult-to-correct astigmatism.

Treatment of lens development anomalies

In case of anomalies in the development of the lens, not accompanied by glaucoma or cataract, special treatment is not required. In cases where, due to a congenital pathology of the lens, a refractive anomaly that cannot be corrected with glasses occurs, the altered lens is removed and replaced with an artificial one.