Surgery to remove cataracts after vitrectomy

Review aim
The aim of this Cochrane Review was to evaluate the evidence regarding the effect of surgery to remove the lens from eyes in which cataracts (clouding of the lens in front of the eye) develop after vitrectomy. Vitrectomy surgery is used to remove the vitreous (the clear gel) in the center of the eye during repair or amelioration of a number of retinal disorders (such as retinal detachment and macular holes or in cases of vitreous hemorrhage).

What was studied in this review?
Vitrectomy can result in the formation or acceleration of cataract. The underlying problem that led to vitrectomy may affect visual acuity, quality of life, and other outcomes after the surgery to remove the cataractous lens.

Main results
We found no randomized controlled trials (trials in which participants had been randomly assigned to one treatment group or another) that evaluated the benefits or risks (or both) of cataract surgery following vitrectomy. Since cataract surgery may lead to loss of vision due to worsening or recurrence of the condition that prompted the vitrectomy, its role in these patients remains unknown. Future trials to address this review question should separate participants by age, the disorder leading to vitrectomy, and the status of the underlying disease process in the opposite eye. Outcomes relevant to patients such as improvement in visual acuity, other measures of vision, and quality of life usually expected from cataract surgery, and harms should be examined both in the short term (six months after cataract surgery) and in the long term (one to two years after cataract surgery).

Key messages
There is an evidence gap as to whether surgery to remove cataracts in people in whose eyes cataracts develop after vitrectomy is better than no surgery.

How up-to-date is the review?
We searched for studies published up to 17 May 2017.

Authors' conclusions: 

There is no evidence from RCTs or quasi-RCTs on which to base clinical recommendations for surgery for postvitrectomy cataract. There is a clear need for RCTs to address this evidence gap. Such trials should stratify participants by their age, the retinal disorder leading to vitrectomy, and the status of the underlying disease process in the contralateral eye. Outcomes assessed in such trials may include changes (both gains and losses) of visual acuity, quality of life, and adverse events such as posterior capsular rupture and retinal detachment. Both short-term (six-month) and long-term (one- or two-year) outcomes should be examined.

Read the full abstract...
Background: 

Cataract formation or acceleration can occur after intraocular surgery, especially following vitrectomy, a surgical technique for removing the vitreous that is used in the treatment of many disorders that affect the posterior segment of the eye. The underlying problem that led to vitrectomy may limit the benefit from removal of the cataractous lens.

Objectives: 

To evaluate the effectiveness and safety of surgery versus no surgery for postvitrectomy cataract with respect to visual acuity, quality of life, and other outcomes.

Search strategy: 

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2017, Issue 5), MEDLINE Ovid (1946 to 17 May 2017), Embase.com (1947 to 17 May 2017), PubMed (1946 to 17 May 2017), Latin American and Caribbean Health Sciences Literature database (LILACS) (January 1982 to 17 May 2017), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com); last searched May 2013, ClinicalTrials.gov (www.clinicaltrials.gov); searched 17 May 2017, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 17 May 2017. We did not use any date or language restrictions in the electronic searches for trials.

Selection criteria: 

We planned to include randomized controlled trials (RCTs) and quasi-RCTs that had compared surgery versus no surgery to remove the lens from eyes of adults in which cataracts had developed following vitrectomy.

Data collection and analysis: 

Two review authors independently screened the search results according to the standard methodological procedures expected by Cochrane.

Main results: 

We found no RCTs or quasi-RCTs that had compared surgery versus no surgery to remove the lens from eyes of adults in which cataracts had developed following vitrectomy.

Health topics: