Lens subluxation syndromes
• Marfan syndrome (AD)
Superotemporal subluxation with intact zonules
In Marfan syndrome, the health of the eye can be affected in many ways, but the principal change is partial lens dislocation, where the lens is shifted out of its normal position.This occurs because of weakness in the ciliary zonules, the connective tissue strands which suspend the lens within the eye. The mutations responsible for Marfan syndrome weaken the zonules and cause them to stretch. The inferior zonules are most frequently stretched resulting in the lens shifting upwards and outwards, but it can shift in other directions as well. Nearsightedness and blurred vision are common, but farsightedness can also result particularly if the lens is highly subluxated. Subluxation (partial dislocation) of the lens can be detected clinically in 80% of patients by the use of a slit-lamp biomicroscope. If the lens subluxation is subtle, then imaging with high-resolution ultrasound biomicroscopy might be used.
Other signs and symptoms affecting the eye include increased length along an axis of the globe, myopia, corneal flatness, strabismus, exotropia, and esotropia.
• Homocystinuria (AR)
Subluxation inferiorly with absent zonules
Other eye anomalies:
- Ectopia lentis – in contrast to Marfan syndrome which features upward ectopia lentis, downward dislocation is the typical finding of homocystinuria[4] or subluxation of lens
- Myopia (nearsightedness)
- Glaucoma
- Optic atrophy
- Retinal detachment
- Cataracts
• Weill-Marchesani (AR and AD)
Subluxation inferiorly with microspherophakia.
Weill–Marchesani syndrome is a rare genetic disorder characterized by short stature; an unusually short, broad head (brachycephaly) and other facial abnormalities; hand defects, including unusually short fingers (brachydactyly); and distinctive eye (ocular) abnormalities. It was named after ophthalmologists Georges Weill (1866-1952) and Oswald Marchesani (1900-1952) who first described it in 1932 and 1939, respectively.
The eye manifestations typically include unusually small, round lenses of the eyes (spherophakia), which may be prone to dislocating (ectopia lentis), as well as other ocular defects. Due to such abnormalities, affected individuals may have varying degrees of visual impairment, ranging from nearsightedness myopia to blindness. Researchers suggest that Weill–Marchesani syndrome may have autosomal recessive or autosomal dominant inheritance.
Eye surgery has been documented to help those with ocular diseases, such as some forms of glaucoma.
However, long term medical management of glaucoma has not proven to be successful for patients with Weill–Marchesani syndrome. Physical therapy and orthopedic treatments are generally prescribed for problems stemming from mobility from this connective tissue disorder. However, this disorder has no cure, and generally, treatments are given to improve quality of life.
Lens subluxation syndromes power point presentations:
Marfan syndrome
Homocystinuria
Ectopia lentis
Lens subluxation syndromes Videos:
Subluxed lens/Ectopia lentis due to Marfan syndrome – Cionni CTR …
Lens subluxation in Marfan syndrome
Lens subluxation syndromes