Late-onset capsular bag distension syndrome following cataract surgery

Abstract

Capsular bag distension syndrome (CBDS) is an unusual cause of late visual impairment after cataract surgery with characteristic features and can be easily treated to rapidly restore visual function. A 74-year-old man presented to the ophthal-mology outpatient clinic with reduced visual acuity and increasing haziness of vision in his left eye over several months. Seven years pre-viously he had undergone uneventful cataract surgery with phacoemulsification and insertion of a posterior chamber lens (+14.5 dioptres Alcon MA60BM, 6.0 mm optic) in the same eye. There had been no postoperative complications and his preoperative best-corrected visual acuity of 6/24 had improved to 6/9 four weeks following surgery. The postoperative spherical equivalent refraction was – 0.125 dioptres. At the current presentation, his best-corrected visual acuity was 6/9 in the right eye and 6/18 in the left eye. Slit lamp biomicroscopic examination revealed a posterior chamber intraocular lens with a distended posterior capsule and an opaque fluid sequestered between the intraocular lens optic and posterior capsule (retrolenticular pseudohy-popyon) (Figure 1). Intraocular pressure was within the normal range and there was no evidence of anterior or posterior segment inflammation. Posterior capsulotomy with Nd:YAG laser was undertaken, and immediately after the posterior capsule was breached, the milky white fluid was observed to pour through the capsulotomy into the vitreous cavity. Upon completion of the capsu-lotomy the sequestered fluid had disappeared from the capsular bag, the posterior capsule disten-sion had resolved with the lens capsule anatomically positioned immediately behind the intraocular lens optic (Figure 2). Immediate post-laser visual acuity was 6/12, and at follow-up six weeks later, this had improved further to 6/9 with no intraocular inflammation. Discussion CBDS is an uncommon, but well recognized cause of reduced vision following cataract surgery. It usually presents in the immediate postoperative period, with shallowing of the anterior chamber, unexpected myopic refraction and accumulation of liquefied substance between the implanted lens and posterior capsule. 1 – 4 It may rarely present many years after surgery, with reduced vision but no significant refractive change. 1,5 The present case demonstrates this unusual presen-tation of delayed postoperative visual impairment and its management, with photographic docu-mentation of the clinical course. Early CBDS presents between 1 day and 2 weeks postoperatively and the most likely expla-nation is that retained viscoelastic from the surgi-cal procedure accumulates behind the intraocular lens (IOL) as the IOL optic occludes the anterior capsular opening made by the capsulorrhexis.