Statistics from Altmetric.com
Up until about 20 years ago, the majority of retinal detachments were operated on by general ophthalmologists and the only technique available was scleral buckling combined where appropriate with subretinal fluid drainage and air tamponade. Now specialist vitreoretinal surgeons perform most of the surgery and have a much greater variety of surgical techniques to choose from. The three views presented here define the available options and their indications as seen by proponents of each technique. The results of scleral buckling without drainage of 91% after one operation and 97% after one further procedure are very impressive and the key to their success is the time consuming and painstaking preoperative examination. I suspect that there are few other groups who would not be tempted to embark on more complicated surgery where breaks had not been identified preoperatively or in cases of primary failure.
Theoretically, there are many reasons as described by Heinmann why primary vitrectomy should improve the success rate and it is disappointing that the results appear to be poorer with a cumulative reattachment rate of 85%, which is lower than that for scleral buckling without subretinal fluid drainage. This, together with the added complications of vitreous surgery such as accelerated lens opacities and entry site tears, not to mention the extra costs, would seem to weaken the case for primary vitrectomy. It is important however not to overlook the high final success rates in more complex cases.
The concept of being able to reattach the retina by a minor office based procedure is appealing for all the obvious reasons, so why is it still not widely practised around the world? The cumulative success rate of 75% is obviously lower than with scleral buckling and the relatively high rate of secondary break formation is a further deterrent. There are also other regional factors such as familiarity with the technique and financial pressures that may influence surgical judgment.
Why then are so many cases of retinal detachment undergoing primary vitrectomy? Part of the reason must be the increased familiarity with the techniques gained from diabetic eye disease and trauma, as well as vitreous surgery for advanced PVR and giant retinal tears. Few vitreoretinal surgeons could not be impressed by the ease of examining the peripheral retina intraoperatively afforded by using modern wide field viewing systems, especially when the view is impaired by pseudophakia or media opacities. This has undoubtedly led to less emphasis on the importance of finding breaks preoperatively and hence a lower threshold for recourse to vitreous surgery. Indeed, there is concern that this trend will have a detrimental effect on the examination skills of the next generation of retinal surgeons, who may have a lower rate of finding retinal breaks preoperatively, and therefore a lower threshold for vitreous surgery.
So what conclusions can be drawn? I suspect most surgeons will continue to perform scleral buckling in one form or another. We should perhaps try to reduce the rate of subretinal fluid drainage as, despite refinements, it appears to adversely affect the results. The multicentre trials of scleral buckling will further refine the role of each technique but it would seem unlikely that primary vitrectomy will be readily adopted for simple detachments where the view is good. Pneumatic retinopexy may become more popular in situations where access to an operating theatre is at a premium, but it is likely that its poorer surgical results and increased complication rate will stop its widespread adoption as a primary treatment for retinal detachment.
It is salutary to note that although 70 years have elapsed since Gonin identified that retinal tears were the cause of retinal detachments, the main reason for failure remains the inability to find and subsequently close the break. At this time, although scleral buckling is probably still the most widely used primary procedure, there is no clearly superior surgical technique.