Abstract
Purpose: :
Late-onset capsular block syndrome (CBS) has been described as a rare complication of cataract phacoemulsification and posterior chamber intra-ocular lens implantation (phaco/PCIOL). We present 3 cases of late-onset CBS seen at Boston Medical Center (BMC), and a review of the literature, to examine how frequently this complication may actually occur, to determine how useful the Pentacam is in establishing a diagnosis and prognosis, and to describe treatment outcomes with YAG posterior capsulotomy.
Methods: :
This is a non-comparative case series of 3 patients who presented to BMC between March and April 2010. The diagnosis of late-onset CBS was based on a distant history of phaco/PCIOL, slit lamp findings of a gap between the PCIOL and posterior capsule filled with a milky substance, and the absence of ocular inflammation.
Results: :
Within a one-month period, 3 patients with unilateral sub-acute decreased vision were seen by the authors in routine clinical settings, and diagnosed with late-onset CBS, occurring 3, 8 and 9 years after uncomplicated phaco/PCIOL. Initial best-corrected visual acuities (BCVA) were essentially unchanged from prior to symptom onset; however, uncorrected visual acuity (UCVA) decreased and patients reported vision clouding and/or metamorphopsia. Two eyes had hyperopic shifts of +1.00 spherical equivalent (SE), and one had a myopic shift of -1.75 SE. All eyes had some degree of retained lens cortex. We performed Oculus Pentacam evaluation for 2 of the 3 eyes, which revealed a dense material between the PCIOL and posterior capsule of 48.2 and 29.9 density units. All 3 eyes were treated with posterior YAG capsulotomy, without complications. Although BCVA was largely unchanged after treatment, all patients reported subjective vision improvement, and refractive shifts improved. The eye with denser fluid by Pentacam analysis had the greatest subjective vision improvement, as well as improvement from UCVA of 20/40 to 20/20.
Conclusions: :
Late-onset CBS is likely much more common than prior reports have suggested. The Pentacam can be a very useful tool for judging the density, and thus probable visual significance, of the milky fluid posterior to the PCIOL, which can help guide the decision to treat. In our experience, posterior YAG-capsulotomy can successfully treat visually significant late-onset CBS.
Keywords: intraocular lens • imaging/image analysis: clinical • cataract