25 G surgery offers enhanced patient comfort as well as faster postoperative recovery.
Since I first performed 25 G vitrectomy surgery in 2001, I have not only continued to use the technique in my practice, but I have in fact expanded its use. I believe that the procedure and instruments are both safe and efficient, and recent innovations have enabled me to increase the number of indications in which I use the technique.
Today's 25 G vitrectomy is very different to the procedure that was introduced seven years ago. The incidence of adverse events is lower than ever, and I have been very impressed by the design and capabilities of the new 25 G instruments. Currently, I use the 25 G tools from Alcon and Bausch & Lomb.
The reductions in traumatic conjunctival and scleral manipulation, postoperative intraocular inflammation and postoperative corneal astigmatism are just some of the theoretical advantages of this form of surgery.1 For me, the most obvious benefit of 25 G surgery over and above either 23 G or 20 G surgery is the incision size; postoperatively, such a minor wound closes both better and faster, thereby reducing the incidence of the most feared complications of sutureless vitrectomy procedures, such as endophthalmitis.
Responding to the criticisms
Some years ago, 25 G surgery was often associated with significant hypotony and wound leak; recent surgical modifications and instrument design enhancements, however, have resulted in a very low incidence of both hypotony and wound suturing.
Instruments used during 25 G surgery have been criticized for their perceived lack of efficiency. In truth, until recently, I used these instruments only to perform macular surgery. I had found that the vitrectors were less efficient than the larger gauge instruments; thus, vitreous removal, although possible, was a time-consuming process. With the new 25 G vitrectors, however, it is now possible to gain the same, if not better, aspiration and cutting rates than those achieved with bigger calibre instruments, and the improved duty cycle makes it possible to achieve exceptional performance. I do not understand why anyone would use bigger instruments when the same surgical outcome can be achieved with instruments that are half the size, in the same timeframe but with better patient comfort. In any case, in those retina pathologies where proximity to the retina is required, a small vitrector is in fact favourable. For example, in fibrovascular proliferations, it is possible to use 25 G instruments successfully to remove epiretinal membrane tissue without the need for either numerous instrument changes or difficult bimanual manoeuvres.
Instrument flexibility cannot be ignored
The biggest inconvenience that I have encountered with 25 G instruments is, without a doubt, the tool flexure, which made working in the periphery of the vitreous chamber very difficult, and for several years caused 25 G surgery to be restricted to uncomplicated cases of vitreous and macular surgery. Thankfully, however, with today's stiffer and more durable instruments, the number of conditions that can be treated with this minimally invasive approach is growing; therefore, I think that this argument is no longer relevant.
I sincerely believe that, as the newer 25 G instruments make their way to the market, those surgeons who remain cynical of their safety and efficiency will become 25 G converts. In fact, results from the American Society of Retina Specialists Preferences and Trends (ASRS PAT) annual survey show that the minimally invasive technique is gaining favour rapidly in the US. According to the 2003 survey, 70% of retina surgeons had never tried the technique, and only 6% owned the instrumentation and used it frequently.2 Just four years later, in 2007, attitudes had changed significantly. This time, the survey revealed that 70% of vitreoretinal surgeons use 25 G technology occasionally and 25% used it in more than 75% of their cases.3 As new data for the latest generation of instruments is made available, I think that we will see even more widespread use of 25 G instruments among the retina community.
Exciting times await
In more general terms, I also believe that we will be seeing a greater integration of pharmacological and surgical therapy for retina conditions; specifically, I think intravitreal anti-VEGF agents will be combined with surgery in the treatment of severe complications of diabetic retinopathy. I also believe sincerely that we will, in the future, combine enzyme therapy with small calibre vitrector surgery to realize the dream of every vitreoretinal surgeon: the complete, safe and fast removal of the vitreous.
I am very happy to be around to witness these exciting times for vitreoretinal research and development. The future will be a promising one, for us and for our patients.
To read Professor Albert J. Augustin's counter-argument, please go to http://www.oteurope.com/2008debates/25G/abandon
1. M.S. Ibarra, et al. Am. J. Ophthalmol. 2005;139:831–836.
2. 2003 American Society of Retina Specialists Patterns and Trends Survey. Poster presented at 2003 Annual ASRS meeting; November, 2003; New York, US.
3. 2007 American Society of Retina Specialists Patterns and Trends Survey. Poster presented at 2007 Annual ASRS meeting; 1–5 December 2007; Palm Springs, California, US.