Risk factors for posterior capsule opacification

Posterior Capsule Opacification: A Review of Experimental Studies

Posterior capsule opacification (PCO) is the most common complication of cataract surgery. It causes a gradual deterioration of visual acuity, which would otherwise improve after a successful procedure. Despite recent advances in ophthalmology, this complication has not been eradicated, and the incidence of PCO can be as high as 10%. This article reviews the literature concerning the pathomechanism of PCO and examines the biochemical pathways involved in its formation and methods to prevent this complication. We also review the reported tests performed in cell cultures under laboratory conditions and in experimental animal models and in ex vivo human lens capsules. Finally, we describe research involving human eyes in the clinical setting and pharmacological methods that may reduce the frequency of PCO. Due to the multifactorial etiology of PCO, in vitro studies make it possible to assess the factors contributing to its complications and search for new therapeutic targets. Not all pathways involved in cell proliferation, migration, and contraction of the lens capsule are reproducible in laboratory conditions; moreover, PCO in humans and laboratory animals may be additionally stimulated by various degrees of postoperative reactions depending on the course of surgery. Therefore, further studies are necessary.

Further Enhancement of Intraocular Open-Capsule Devices for Prevention of Posterior Capsule Opacification

Purpose

We improve the intraocular open-capsule devices (IOCD) for the prevention of posterior capsule opacification (PCO).

Methods

A total of 45 New Zealand rabbit eyes were divided into six similar groups after crystalline lens evacuation. Each group was implanted with a hydrophilic intraocular lens (IOL) and a hydrophilic IOCD of different designs. In the first experiment (Part A), a square design ring with and without large apertures was compared to a round design ring without apertures. In the second experiment (Part B), a square design ring with large apertures was compared to square design IOCDs with small apertures of high and low density. PCO and Soemmering's ring were evaluated clinically, by the Miyake Apple view, and histologically. The results were compared to a control group of eyes implanted with a hydrophilic IOL only.

Results

All devices showed significant prevention of PCO and Soemmering's ring compared to the control group. Part A: the square design with apertures had the lowest level of peripheral lens epithelial cells proliferation (protrusions). Part B: modifying the size and density of the apertures had no influence on those protrusions.

Conclusions

The IOCD significantly reduced the rate of PCO and its precursor, Soemmering's ring. The rings with the square edges and apertures produced the best results. The study was underpowered to determine the influence of the apertures design.

Translational Relevance

The IOCD has the potential to prevent up to 80% of the PCO cases; the most common complication after cataract surgery. The design of the ring is important for its success.

Care of Older Adults: Role of Primary Care Physicians in the Treatment of Cataracts and Macular Degeneration

This article aims to facilitate optimal management of cataracts and age-related macular degeneration (AMD) by providing information on indications, risk factors, referral guidelines, and treatments and to describe techniques to maximize quality of life (QOL) for people with irreversible vision loss. A review of PubMed and other online databases was performed for peer-reviewed English-language articles from 1980 through August 2012 on visual impairment in elderly adults. Search terms included vision loss, visual impairment, blind, low vision, QOL combined with age-related, elderly, and aging. Articles were selected that discussed vision loss in elderly adults, effects of vision impairment on QOL, and care strategies to manage vision loss in older adults. The ability of primary care physicians (PCPs) to identify early signs of cataracts and AMD in individuals at risk of vision loss is critical to early diagnosis and management of these common age-related eye diseases. PCPs can help preserve vision by issuing aptly timed referrals and encouraging behavioral modifications that reduce risk factors. With knowledge of referral guidelines for soliciting low-vision rehabilitation services, visual aids, and community support resources, PCPs can considerably increase the QOL of individuals with uncorrectable vision loss. By offering appropriately timed referrals, promoting behavioral modifications, and allocating low-vision care resources, PCPs may play a critical role in preserving visual health and enhancing the QOL for the elderly population.

[Posterior capsule opacification, capsular bag distension syndrome, and anterior capsular phimosis: A retrospective cohort study]

OBJECTIVE

To determine the incidence and the risk factors involved in the development of the three main postoperative capsular complications: posterior capsule opacification (PCO), capsular bag distension syndrome (CBDS), and anterior capsular phimosis syndrome (ACP).

SUBJECTS, MATERIAL AND METHODS

A retrospective cohort study was conducted on 801 patients submitted to cataract surgery in the ophthalmology unit of Hospital del Henares (Madrid) from March 2, 2009 to February 28, 2010. Computerized clinical charts were reviewed during July 2012. PCO was studied using the Kaplan-Meier method (log rank test).

RESULTS

A total of 167 patients developed PCO. No association could be demonstrated between PCO and age, sex, diabetes mellitus, phaco technique, IOL model, tamsulosin intake, glaucoma, and age-related macular degeneration. Three patients developed CBDS, all of them have received and Akreos Adapt AO(®) (Bausch & Lomb). Two of them were young men who had received surgery for posterior subcapsular cataracts. Three patients developed ACP, 2 of whom had received a MicroSlim(®) IOL (PhysIOL).

CONCLUSIONS

No association was found between PCO and any of the studied variables. Male gender, young age, subcapsular cataract and large non-angulated lens such as Akreos Adapt AO(®) could be associated with CBDS. ACP could be more frequent when microincision IOLs (like MicroSlim(®)) are implanted.