Bilateral Ectopia Lentis in a case of Marfan Syndrome – An ultrasound diagnosis

Introduction –

Marfan syndrome is an inherited disorder that affects connective tissue which supports and anchor body parts and organs structures . It most commonly affects heart , eyes , blood vessels and sketelal system.

There is no any  unique sign and symptom of this disease but constellation of long limbs, dislocation of lenses and aortic root dilation are the key findings to make the diagnosis with confidence . Dr. Subhash Tailor , MD  Bhilwara [ Rajasthan ]  is presenting a case of Marfan syndrome whose ocular ultrasound revealed bilateral dislocation of lens [Ectopic lentis].

Case report –

A 25 years old man attended my clinic for ocular ultrasound , asked for decreased vision.  His medical , clinical and genetic history was notably suggesting a case of Marfan syndrome . Ocular USG was performed with a voluson – 730 [ wipro GE ] system with 6 to 12 MHZ broad band linear probe . Examination of his one eye revealed absence of crystalline lens at its position and it was seen lodged posteriorly near retina as a well defined oval echogenic area [ see figure  ]. The second eye was also attempted and revealed the same findings of dislocated lens , suggesting bilateral ectopia lentis . The dislocation was typically supero-temporal . The other ocular  findings were obliterated anterior chamber, some low level intragel internal echos indicating degenerative changes and slightly increased axial diameter of the eye balls . No retinal detachment was seen .

Discussion –

Marfan syndrome is a disorder of connective tissue that holds the structures in position   in various parts of body . So weakness in the ligaments that holds the lens in place causes subluxation and even complete dislocation of ocular crystalline lens , called ectopia lentis . In this my case bilateral ectopia lentis noted with subtle degenerative echos in the vitreous  gel , and slightly increased axial diameter of the eye balls  . No evidence of retinal detachment was  found in either eye . The dislocation of lens in  Marfan syndrome is classically  superotemporal whereas in similar condition Homocystinuria , the dislocation is infero nasal type . In Marfan syndrome ectopia lentis noted in about 80% of cases.

The other ocular manifestations are glaucoma and retinal detachment . The diagnosis of ectopia lentis in this case was straight forward because of absence of lens at its normal position , and presence of the cataractus  [ small oval echogenic structure ] lens dislocated and lodged posteriorly near retina in both eyes , suggesting bilateral ectopia lentis in the light of  appropriate clinical settings.

Figure – Axial US images of both eye balls showing a well defined oval echogenic structure posteriorly near retina , s/o ectopia lentis  . Some low level intragel internal echoes  also evident.