Abstract and Introduction

Abstract

INTRODUCTION: To identify variables associated with primary anatomical outcome following vitrectomy and internal tamponade for rhegmatogenous retinal detachment (RD).

METHODS: A retrospective analysis of prospectively collected data, using a database of RD treated with vitrectomy and internal tamponade. Collected data complied with the RCOphth Retinal Detachment Dataset. The main outcome measure was anatomical failure within six months of surgery.

RESULTS: There were 6377 vitrectomies. 869 eyes were excluded, either because no outcome was recorded, or inadequate follow up, leaving 5508 operations for analysis. 63.9% of patients were male, and the median age was 62. Primary anatomical failure occurred in 13.9%. On multivariate analysis, the following were associated with increased risk of failure: age <45, or >79, inferior retinal breaks, total detachment, one quadrant or greater inferior detachment, low density silicone oil, and presence of proliferative vitreoretinopathy. C₂F₆ tamponade, cryotherapy, and 25 G vitrectomy, were associated with reduced risk of failure. The area under the receiver operator curve was 71.7%. According to this model, 54.3% of RD are at low risk (<10%), 35.6% are at moderate risk (10–25%), and 10.1% are at high risk (>25%) of failure.

CONCLUSIONS: Previous attempts to identify high risk RD have been limited by small numbers, the inclusion of both scleral buckling and vitrectomy, or by excluding some types of RD. This study examined outcomes in unselected RD, treated by vitrectomy. Identification of the variables associated with anatomical outcome after RD surgery enables accurate risk stratification, which is valuable for patient counselling and selection, and for future clinical trials.

Introduction

Some of the factors that affect anatomical success after retinal detachment (RD) surgery are relatively well understood, and grading systems have been produced that enable surgeons to predict the likelihood of anatomical re-attachment with a single operation^[1–6]. However, some of these publications include both scleral buckling and vitrectomy^{[1, 4, 7, 8]} The risk factors for failure are unlikely to be the same for these very different operations. Other reports have only included sub-sets of primary retinal detachments^{[3, 7]}, or have included re-operations^[8]. Various different outcomes and definitions of anatomical success have been used^{[4, 5, 8]}. Overall, the number of eyes included in each study has been small, Q1 -Q5 with only one report including more than 1 000 eyes^[8].

Previous authors have shown that the risk of primary anatomical failure may be increased by proliferative vitreoretinopathy (PVR)^{[3–6, 8]}, a greater extent of retinal detachment^{[3, 4, 9]}, foveal detachment^[10] or total detachment^{[5, 8]}, the number of breaks in detached retina^{[5, 7]}, inferior breaks^[5], the size of breaks^[7], pseudophakia^[3], hypotony or choroidal detachment^[8], and the use of cryotherapy^[7]. It is not surprising that there is little agreement between these studies, given the different inclusion criteria, interventions, and end-points, and the relatively small numbers of cases included.

In order to identify, and quantify, the variables associated with anatomical outcome of primary RD treated by pars plana vitrectomy and internal tamponade, we examined data from 5508 primary RD operations. In contrast to some of the other studies of risk factors, we included all primary rhegmatogenous RD, and used the outcome of primary anatomical failure, as this has been shown to be associated with worse functional outcomes.^{[11, 12]}