Lens-sparing surgery for retinopathy of prematurity

Letters to the Editor Author reply Dear Editor: We appreciate the comments of Drs. Gills and Rowsey and recognize their concerns and suggestions regarding prevention of postoperative endophthalmitis. They indicate a selfreported incidence of infection at 1 per 20,000 cases, which is markedly lower than the presently accepted rate of nearly 8 per 10,000 cases. With respect to infection prophylaxis, their practice concurs with the recognized literature about preoperative preparation with topical povidone–iodine. However, other methods have not been submitted to the peer review process nor determined to be clearly relevant to clinical outcomes. Specifically, they mention use of microfiltration of fluids, instillation of intracameral antibiotics at the close of surgery, meticulous surgical technique, and evaluation of (and presumably attention to) low intraocular pressure in the early postoperative period (as a measure of potential incompetent closure of the incision). It could be that any or all of their measures are beneficial to the prevention of postoperative infection. However, in the absence of appropriate controlled investigations of their methods, the information remains anecdotal and would be categorized as III-C in the current system for evaluation of evidencedbased medical literature, indicating that the clinical relevance of their antimicrobial prophylaxis cannot be stated with certainty.1 In our published review of the literature regarding infection prophylaxis, we found an absence of preventative methods that could be categorized as A-I, which would indicate a strong association with clinical outcome as determined by an appropriately randomized and reported controlled trial.2 We were careful to mention that the best methods for prophylaxis may not have been properly studied or reported and that the peer-reviewed literature may not, therefore, be representative of the most efficacious means for infection prophylaxis. Drs. Gills and Rowsey underscore the concern that the state of the literature might not be the state of the art. Although carefully organized and orchestrated nationwide investigations have been performed to evaluate management of diabetic retinopathy, retinal vein occlusion, macular degeneration, optic neuropathy, melanoma, established endophthalmitis, etc., there have been no large-scale, cooperative or controlled studies that have been performed to determine the best methods for prevention of endophthalmitis. The need for such investigations is apparent. SAMUEL MASKET, MD Los Angeles, California THOMAS A. CIULLA, MD Indianapolis, Indiana MICHAEL B. STAAR, MD New York, New York References 1. Minckler D. Evidence-based ophthalmology series and contentbased continuing medical education for the journal [editorial]. Ophthalmology 2000;107:9 –10.

2. Ciulla TA, Starr MB, Masket S. Bacterial endophthalmitis prophylaxis for cataract surgery: an evidence based update. Ophthalmology 2002;109:13–24.

Lens-Sparing Surgery for Retinopathy of Prematurity Dear Editor: Capone and Trese (Ophthalmology 2001;108:2068 –70) suggested that the use of lens-sparing vitrectomy for stage 4A retinopathy of prematurity (ROP) reduces the progression of the disease and improves the patient’s visual prognosis. After abandoning pars plana vitrectomy lensectomy for stage 5 ROP (due to the very poor rate of visual success at 4 years of follow-up), our group in Argentina has been performing three-port lens-sparing vitreous surgery with endophotocoagulation for stages 4A and 4B ROP. Of eight cases of stage 4A, 87.5% had good anatomic outcomes (unpublished data) and maintained central steady fixation. The other 12.5% (one eye) progressed to a worse stage of the disease, with both poor anatomic and poor functional results. Four of the stage 4A ROP eyes we treated had no peripheral retinal laser photoablation before surgery. With these eyes we obtained the best surgical outcome. At the time of the procedure, the organized vitreous was easier to cut and the retina was less rigid, so that when the traction was liberated we could observe the retina flattening smoothly. Conversely, in the eyes that had been treated with laser before surgery we found the organized vitreous more difficult to manipulate and the retina more rigid, thus increasing the risk of iatrogenic retinal tearing and detachment. Of course, we understand our experience is very limited, but the difference observed was remarkable; therefore, we thought it should be reported. We agree with Drs. Capone and Trese that the time of the surgical intervention is a key factor in achieving good results with this treatment. In our cases that were not treated with laser before surgery, the infants were brought to our institution with vascular activity (dilation and tortuosity). After releasing the traction a complete endophotocoagulation was carried out in the entire avascular zone to interrupt the pathogenic mechanism that leads to stages 4B and 5. As explained by Capone and Trese, timing is the most important issue in preventing blindness in any stage of the disease, and in remote places of our country where there is no ROP screening availability, early surgical treatment may be an alternative to consider. JOSE´ D. LUNA, MD LEANDRO J. CARIBAUX, MD VICTOR E. REVIGLIO, MD CLAUDIO P. JUAREZ, MD Co´rdoba, Argentina

Lacquer Crack Formation after LASIK Dear Editor: The possible effects of LASIK on the posterior segment of the eye are not thoroughly known. Retinal detachment after LASIK, choroidal neovascularization, macular hemorrhage, and macular hole after LASIK have been described.1– 4

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