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Ectopia Lentis: Weill Marchesani Syndrome Review Articles Ectopia Lentis: Weill Marchesani Syndrome HL Trivedi*, Ramesh Venkatesh** Abstract A 20 yr old boy came to our OPD with decreased vision since 3 yrs. He complained of double vision in both the eyes. There were no other ocular or systemic complaints. On systemic exami- nation, the boy had a short stature compared to his age, short fingers and limbs. On ophthalmic examination, Vn in RE was 20/200 and LE was finger counting 5 ft. Cornea and other ocular adnexa were normal. The lens was spherical in shape and dislocated in the anterior chamber. There were no signs of iridocyclitis. Intraocular tension in both eyes was 20.6 mm Hg. Posterior segment evaluation was normal. Introduction of lens displacement. ctopia lentis is defined as displacement Frequency Eor malposition of the crystalline lens of the eye. The lens is considered dislocated or United States luxated when it lies completely outside the Ectopia lentis is a rare condition. Incidence lens patellar fossa, in the anterior chamber, in the general population is unknown. The free-floating in the vitreous, or directly on most common cause of ectopia lentis is the retina. The lens is described as subluxed trauma, which accounts for nearly one half when it is partially displaced but contained of all cases of lens dislocation. within the lens space. In the absence of Mortality/Morbidity trauma, ectopia lentis should evoke suspicion for concomitant hereditary systemic disease Ectopia lentis may cause marked visual disturbance, which varies with the degree of or associated ocular disorders. lens displacement and the underlying Weil Marchesani syndrome is also known aetiologic abnormality. as Marchesani’s Syndrome. Sex The condition is named after Oswald Marchesani and Georges Weill. Males appear more prone to ocular trauma than females; therefore, a male Pathophysiology preponderance has been reported. Male and Disruption or dysfunction of the zonular female frequency varies with the aetiology of fibres of the lens, regardless of cause (trauma the lens displacement. or heritable condition), is the underlying Age pathophysiology of ectopia lentis. The degree of zonular impairment determines the degree Ectopia lentis can occur at any age. It may be present at birth, or it may manifest late in *Associate Professor; **Resident, Department of life. Ophthalmology, TNMC and BYL Nair Hospital, Inheritance Pattern : Autosomal recessive Mumbai 400 008. Bombay Hospital Journal, Vol. 51, No. 1, 2009 49 Clinical History A 20 yr old boy came to our OPD with decreased vision since 3 yrs. He complained of double vision in both the eyes. There were no other ocular or systemic complaints. On systemic examination, the boy had a short stature compared to his age, short fingers and limbs (Figs. 1-3). On ophthalmic examination, Vn in RE was 20/200 and LE was finger counting 5 ft. Cornea and other ocular adnexa were normal. The lens was spherical in shape and dislocated in the anterior chamber. There Fig. 2 : Short toes. were no signs of iridocyclitis. Intraocular tension in both eyes was 20.6 mm Hg. Posterior segment evaluation was normal. Patient was operated in the left eye with lensectomy through the limbal route and scleral fixated intraocular lens implantation in the same sitting. Post operatively patient Fig. 3 : Short fingers. vision improved to 20/60 in the left eye with no other complications. l Common presenting symptoms (visual disturbance) m Decreased distance visual acuity (secondary to astigmatism or myopia) m Poor near vision (loss of accommodative power) m Monocular diplopia l Obtain a detailed history investigating possible systemic disease associations. l Cardiovascular disease (e.g., Marfan Fig. 1 : Boy with short stature. syndrome) 50 Bombay Hospital Journal, Vol. 51, No. 1, 2009 l Skeletal problems (secondary to amblyopia). m Marfan syndrome l Retinoscopy and refraction m Weil-Marchesani syndrome m Careful retinoscopy and refraction is m Homocystinuria essential, often revealing myopia with astigmatism. l Pertinent family history m Keratometry may help ascertain m Consanguinity degree of corneal astigmatism. m Mental retardation l Slit lamp examination m Unexplained deaths at young age m Evaluate lens position, and identify (e.g., autosomal recessive conditions, phacodonesis or cataract. including homocystinuria, hyper- lysinaemia, ectopia lentis et pupillae, m Measure intraocular pressure. or sulphite oxidase deficiency) Elevation may indicate secondary glaucoma. Physical m Causes of glaucoma in ectopia lentis A paediatrician or an internal medicine include the following: (1) pupillary physician should perform a comprehensive block, (2) phacoanaphylaxis or physical examination of patients with ectopia phacolytic, (3) posttraumatic angle lentis of undetermined aetiology because of recession, (4) poorly developed angle the commonly associated hereditary systemic structures, and (5) lens in the disorders. The ocular examination should anterior chamber. include the following: l Dilated fundus examination: Retinal l Vision detachment is one of the most serious m Ectopia lentis is potentially visually consequences of a dislocated lens. debilitating. l Echography: Axial length measurement m Visual acuity varies with the degree may be of benefit (patients with Marfan of malpositioning of the lens. syndrome have large globes). m Amblyopia is a common cause of Causes decreased vision in congenital ectopia The numerous causes of ectopia lentis can lentis and is preventable and be classified as follows: treatable. l Traumatic dislocation (most common l External ocular examination cause) m Attention to orbital anatomy is l Hereditary ectopia lentis without important to evaluate for hereditary systemic manifestations malformations (eg, enophthalmos with facial myopathic appearance m Single (isolated) ectopia lentis is seen in patients with Marfan characterized by autosomal dominant syndrome). inheritance with the genetic defect located on chromosome 15, causing a m Measure corneal diameter dysfunctional zonular apparatus. (megalocornea is associated with Microspherophakia is common. Marfan syndrome). Although most often present at birth, m Strabismus is not uncommon Bombay Hospital Journal, Vol. 51, No. 1, 2009 51 late onset has been described. Typically, the lens is displaced supertemporally. m Ectopia lentis et pupillae is characterized by asymmetric eccentric pupils that are displaced in the opposite direction of the lens Fig. 4 : Small shallow orbits. dislocation (toward the most progressing to complete dislocation. dysfunctional zonular fibres). The Pupillary block glaucoma is common; condition usually is bilateral and therefore, prophylactic laser typically autosomal recessive. The peripheral iridotomies are irides often appear atrophic with recommended. transillumination defects on slit lamp examination. Cataracts commonly m Sulphite oxidase deficiency are seen. m Hyperlysinaemia. l Systemic conditions commonly associated l Primary ocular disorders associated with with ectopia lentis ectopia lentis m Marfan syndrome m Congenital glaucoma/buphthalmos m Homocystinuria m Pseudoexfoliation syndrome m Weil-Marchesani is a rare syndrome m Syphilis/chronic uveitis characterized by skeletal m Retinitis pigmentosa malformations (e.g., short stature, m Megalocornea brachycephaly, limited joint mobility, well-developed muscular appearance) m Aniridia and ocular abnormalities (e.g., ectopia m Hypermature cataract lentis, microspherophakia, lenticular m Intraocular tumour myopia). Small shallow orbits (Fig. 4), m High myopia mild maxillary hypoplasia, narrow l Systemic diseases rarely associated with palate, small spherical crystalline ectopia lentis lenses, myopia with or without glaucoma, frequent ectopia lentis, m Ehlers-Danlos syndrome occasional blindness, malformed and m Crouzon disease malaligned teeth, and cardiac defects m Refsum syndrome are the features of Weil Marchesani m Kniest syndrome syndrome. Late ossification of the epiphyses is a constant feature. m Mandibulofacial dysostosis The inheritance pattern is not well m Sturge-Weber syndrome understood; usually autosomal m Conradi syndrome recessive. Microspherophakia is the m Pfaundler syndrome most prominent feature of this m Pierre Robin syndrome syndrome. High incidence of lens subluxation occurs inferiorly, often m Wildervanck syndrome m Sprengel deformity 52 Bombay Hospital Journal, Vol. 51, No. 1, 2009 Workup posterior migration. Surgical Lab Studies treatment will then be needed to prevent further complications. l Perform appropriate diagnostic and laboratory evaluation, if a hereditary m Treatment of a dislocated lens in the condition is suspected (e.g., cardiac vitreous is surgical; however, many evaluation for Marfan syndrome, check vitreoretinal surgeons may advocate serum and urine levels of homocysteine observation if no visual disturbance or methionine for homocystinuria). or impending retinal complication is apparent. Treatment Surgical Care Medical Care Lens surgery in ectopia lentis is technically Without an antecedent history of trauma, challenging, and the numerous techniques patients with ectopia lentis may possess a and strategies are beyond the scope of this systemic disease with potentially deleterious article. effects; therefore, comanagement with the l Indication for lensectomy patient’s paediatrician or internist is essential. Dietary restriction may be partially effective m Lens in the anterior chamber in patients with homocystinuria. Repair of an m Lens-induced uveitis impending dissecting
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