Perfluorocarbon in the Treatment of Giant Retinal Tears

  • Published on
    30-Dec-2016

  • View
    214

  • Download
    0

Embed Size (px)

Transcript

<ul><li><p>Letters to the Editor </p><p>Perfluorocarbon in the Treatment of Giant Retinal Tears Dear Editor: We have recently managed two cases of retinal detach-ment due to giant retinal tear, with vitrectomy and per-fluorocarbon liquid. The first involved a 270 0 retinal tear, managed by lensectomy (due to posterior synechiae), vit-rectomy, perfluorodecalin, and 20% sulfur hexafluoride (SF6 ) exchange; this patient's retina subsequently rede-tached due to proliferative vitreoretinopathy and was suc-cessfully reattached with membrane peeling, 20% SF6, and a broad encircling scleral buckle. In the second case, the tear extended 1500 , and was managed by vitrectomy, per-fluoro-octane, and 20% SF6 exchange; the patient's retina remains attached at last review. </p><p>In both cases, we injected the perfluorocarbon liquid over the optic disc, taking care to stop the injection when the liquid approached the posterior edge of the tear, before embarking on retinal cryopexy and indirect laser photo-coagulation. In a recent article by Kreiger and Lewis (Ophthalmology 1992;99:491-7), the perfluoro-octane fill is clearly demonstrated (Fig 2) as extending anterior to the giant tear. As originally described by Chang et aI, I in the management of giant retinal tears, the perfluorocarbon liquid was only instilled to the posterior margin of the tear. Indeed, in a discussion paper,2 Kreiger observes that the interfacial tension of perfluorocarbon liquid is insuf-ficient to prevent it entering the subretinal space in large breaks. Can Kreiger and Lewis please clarify these seem-ingly disparate points? </p><p>The anterior subretinal fluid was removed by Chang et all by undertaking air-fluid exchange anterior to the perfluorocarbon liquid without the flute needle in the (anterior) subretinal space. The complete vitreous cavity fill demonstrated by Kreiger and Lewis in their article, if not preceded by resection of the anterior retinal flap up to the ora serrata as they have described, would unavoid-ably cause perfluorocarbon liquid accumulation under the anterior retinal flap as the subretinal fluid is displaced anteriorly by the perfluorocarbon liquid. </p><p>Last, Kreiger and Lewis demonstrate in Figure 3 en-dophotocoagulation to the anterior as well as posterior margin of the giant retinal tear. In our recent experience, retinal cryopexy or photocoagulation even to the posterior edge requires scleral indentation, not demonstrated in Figure 3. Again, we would wonder if the slight pouting of the posterior edge of the tear due to the associated scleral indentation would not invariably be associated with pos-terior subretinalleakage of perfluorocarbon liquid when the fill extends anterior to it. </p><p>ALAN LUCKIE, FRACO EVERETT AI, MD WAYNE FuNG, MD San Francisco, California </p><p>References </p><p>1. Chang S, LincoffH, Zimmerman NJ, Fuchs W. Giant retinal tears. Surgical techniques and results using perfluorocarbon liquids. Arch Ophthalmol 1989;107:761-6. </p><p>2. Kreiger AE. Discussion of: Chang S, Reppucci Y, Zim-merman NJ, et al. Perfluorocarbon liquids in the manage-ment of traumatic retinal detachments. Ophthalmology 1989;96:785-92. </p><p>Authors'reply </p><p>In the ten cases reported by us in Ophthalmology in 1992, we brought the perfluorocarbon liquid bubble anterior to the edge of the giant retinal tears in all instances. This could be done safely and effectively because there was no traction on the edge of the tear. None of our cases had residual periretinal traction at the time of perfluorocarbon liquid injection. In addition, almost all of the basal vit-reous and the anterior edge of the retinal tear had been removed during careful radical anterior vitrectomy. This was done after lensectomy and with deep scleral depres-sion as is discussed in our article. </p><p>We would like to stress that this anterior dissection is an essential part of the operation because it eliminates traction and provides space for the anterior portion of the bubble to work properly. It also prevents intraocular fluid from being displaced under the anterior retinal flap as is mentioned by Drs. Luckie, Ai, and Fung. </p><p>We have found by experience that the interfacial ten-sion of the bubble is sufficient to flatten the retina without entering the subretinal space if there is no centripetal trac-tion on the edge of the tear. The surgeon must monitor the edge of the tear during this part of the operation care-fully to be sure that the break is flattening as expected. </p><p>Although in many cases photocoagulation of the pos-terior edge of the retinal tear can be accomplished without scleral depression through using the indirect ophthal-moscope-mounted laser, we often use scleral depression during coagulation while the perfluorocarbon liquid is still in place. Again, if there is no residual traction and the edge of the tear is flat, we have not observed any "pouting" of the retinal edge from scleral depression, nor have we seen any migration of liquid or air under the retina. Treatment of the anterior border of the tear (the ciliary epithelium of the pars plana in this instance) may be con-troversial; but it is done to prevent pars plana detachment, which may dissect circumferentially around the border of the posterior photocoagulation barrier. </p><p>We thank Drs. Luckie, Ai, and Fung for their interest in our article and for their helpful comments. </p><p>ALLAN E. KREIGER, MD HILEL LEWIS, MD Los Angeles, California </p><p>581 </p></li></ul>