Ectopia Lentis & Lens Subluxation

Zonular fibers, composed largely of fibrillin-1 microfibrils, anchor the lens equator to the ciliary body, maintaining central lens position and enabling accommodation. Ectopia lentis is displacement of the crystalline lens from its normal position due to weakness, stretching, or rupture of these zonular fibers, ranging from mild subluxation to complete dislocation.

In Marfan syndrome, fibrillin-1 mutations weaken zonular fibers, causing progressive stretching and subluxation, typically supero-temporally.³ Trauma can mechanically disrupt zonules focally or diffusely. Regardless of cause, a severely subluxated or dislocated lens can obstruct the pupil or angle (precipitating angle-closure glaucoma), incite lens-induced uveitis if the capsule is compromised, or contribute to vitreoretinal traction and retinal detachment risk.²

Patients may be asymptomatic with mild subluxation, or present with blurred vision, monocular diplopia, and glare from a displaced lens edge. Severe subluxation can present acutely with pain and red eye from angle-closure or lens-induced inflammation.

Key differentials by pattern: Marfan syndrome (bilateral, supero-temporal, with cardiovascular/skeletal features), homocystinuria (variable/inferior, with thromboembolic features), traumatic zonular dialysis (unilateral, trauma history), Weill-Marchesani syndrome (microspherophakia, short stature), simple/isolated ectopia lentis, and pseudoexfoliation-associated zonular weakness in older patients.

Diagnosis is primarily clinical via slit-lamp exam (ideally dilated) demonstrating degree and direction of displacement, supplemented by systemic evaluation (physical exam, echocardiography, genetic testing using the Ghent criteria) to confirm an underlying syndromic cause.³ Cataracta pulverulenta (fine central nuclear opacities) can be an atypical Marfan presentation even without overt ectopia lentis, and should raise suspicion for an underlying connective tissue disorder in a pediatric cataract patient.³

Mild, stable subluxation without visual axis compromise can be managed conservatively with refractive correction and monitoring. Surgical management (lensectomy with or without IOL) is indicated for visually significant subluxation, lens-induced complications, or angle-closure risk.² For eyes with inadequate capsular support, sutureless intrascleral one-piece IOL fixation achieved significant visual acuity improvement (mean logMAR 0.50 to 0.09) with good centration/stability at 12 months, though with expected endothelial cell density reduction and occasional macular edema or haptic exposure.¹ For extremely unstable lenses, specialized techniques like "Best Pick and Hold" with "Wrap and Roll" (using microvitreoretinal blades and a vitrectomy cutter) reduce intraoperative complications like capsular fragment loss into the vitreous.²

• Direction of subluxation is a useful clue: supero-temporal suggests Marfan, inferior/variable suggests homocystinuria
• Cataracta pulverulenta can be an atypical Marfan presentation even without overt ectopia lentis³
• Sutureless intrascleral IOL fixation is safe and effective for ectopia lentis with poor capsular support¹
• Extremely subluxated lenses need specialized surgical technique to avoid capsular fragment loss into the vitreous²
• Common pitfall: assuming all ectopia lentis is Marfan-associated without considering direction/systemic features
• Common pitfall: missing an underlying systemic diagnosis, delaying important cardiovascular evaluation