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Inverted pneumatic retinopexy
Letters to the Editor References 1. Chang TS, Pelazk CD, Nguyen RL, et al. Inverted pneumatic retinopexy: a method of treating retinal detachments associated with inferior retinal breaks. Ophthalmology 2003;110:589 –94. 2. Hart RH, Vote BJ, Borthwick JH, et al. Loss of vision caused by expansion of intraocular perfluoropropane (C(3)F(8)) gas during nitrous oxide anesthesia. Am J Ophthalmol 2002;134: 761–3.
Author Reply Dear Editor: We agree with Dr Schechter that after successful reattachment of the retina intraocular gas tamponade may have deleterious effects on vitreoretinal anatomy. Our initial experience with inverted pneumatic retinopexy involved expansile gas tamponade. This decision was predicated on our desire for a generous gas bubble to allow maximal surface contact. Although we have had some success with room air as a source of tamponade, this is most effective in compliant patients with the causative break at 6-o’clock. The limited duration of tamponade with room air and the difficulty patients have inducing tamponade for breaks adjacent to 6-o’clock are factors in favor of expansile gases. In light of our experience with inverted pneumatic retinopexy and our observation of rapid subretinal fluid accumulation, I now routinely use room air for retinal detachments with causative breaks in the superior quandrants. Patients treated in a morning clinic (i.e., intravitreal injection of room air) are typically brought back at the end of the day for laser application. Although the technique of inverted pneumatic retinopexy is somewhat unorthodox and may not be appropriate for some patients, its proof of concept has tested several pathophysiologic paradigms and has expanded my understanding of pneumatic retinopexy in general. Most importantly, inverted pneumatic retinopexy provides an additional officebased treatment option for patients with inferior retinal detachments. TOM S. CHANG, MD Los Angeles, California
Dear Editor: Chang et al1 describe their success in treating retinal detachments associated with inferior retinal breaks and imply that pneumatic treatment of inferior retinal detachments “has not been previously described in the peer-reviewed literature.” However, unless one is absolutely certain of the total history of any new procedure, such claims often prove to be spurious or misleading, as it is here. Literature searches, particularly using online sources, can miss key references not in the databases used or not properly indexed. The reader of an article whose authors claim to be first to describe a procedure does not know for certain that an extensive literature search was conducted by the authors. Ironically, one of the key articles overlooked was published in Ophthalmology 15 years earlier. In an article entitled “Pneumatic Repair of Primary and Secondary Retinal Detachments Using a Binocular Indirect Ophthalmoscope La-
ser Delivery System”,2 Dr Eller and I described and illustrated with retinal drawings 22 cases of retinal detachment treated pneumatically after laser retinopexy, 20 of which were successfully repaired. For each of the 8 retinal detachments that had holes located in the inferior quadrants (between 4-o’clock and 8-o’clock), appropriate dependent positioning was performed. All of these eyes were successfully repaired pneumatically. Three years later, we also reported that, though many suggest that pneumatic retinopexy is successful only with breaks located in the superior 8 quadrants, “in our experience, some patients with inferior breaks may be managed with pneumatic retinopexy”.3 Finally, in the monograph Pneumatic Retinopexy: A Clinical Symposium,4 I also made the point that inferior retinal detachments with inferior breaks may be managed by pneumatic retinopexy. I am delighted to see that others are having success in using pneumatic retinopexy for inferior breaks. However, I suggest that if a journal article claims that something new is being described, the authors be compelled to reiterate what specific efforts were expended to back up such a claim, including details of the databases used. Certainly, it is much safer to state that “little attention has been given to” than to directly claim as these authors did that they were the first to describe, in the peer-reviewed literature, that pneumatic retinopexy can be applied for inferior retinal detachments. As you know with literature searches, there is no statistical parameter to guide the reader as to the validity of a firstto-publish claim. Many journals do not allow such claims to be made for this reason. This is in contrast to clinical research, where, if no difference is found between the outcomes of 2 procedures, the authors are usually compelled to state the power or certainty that no difference exists. THOMAS R. FRIBERG, MD Pittsburgh, Pennsylvania References 1. Chang TS, Pelzek CD, Nguyen RL, et al. Inverted pneumatic retinopexy. A method of treating retinal detachments associated with inferior retinal breaks. Ophthalmology 2003;110:589 –94. 2. Friberg TR, Eller AW. Pneumatic repair of primary and secondary retinal detachments using a binocular indirect ophthalmoscope laser delivery system. Ophthalmology 1988;95:187– 93. 3. Semin Ophthalmol 1991;6:27–35. 4. Tornambe PE, Grizzard WS, eds. Pneumatic Retinopexy: A Clinical Symposium. Des Plaines, IL: Greenwood Publishing; 1999:117–29.
Author reply Dear Editor: Dr Friberg appropriately points out an important error of omission in our article. After a review of the articles pointed out in his letter, I agree that ownership of the original idea began with his initial description in Friberg and Eller.1 This error of omission had occurred despite a careful electronic search for articles during preparation of the manuscript. After receiving Dr Friberg’s letter, I took the opportunity of repeating this MEDLINE search again using the National
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Author Reply Dear Editor: We agree with Dr Schechter that after successful reattachment of the retina intraocular gas tamponade may have deleterious effects on vitreoretinal anatomy. Our initial experience with inverted pneumatic retinopexy involved expansile gas tamponade. This decision was predicated on our desire for a generous gas bubble to allow maximal surface contact. Although we have had some success with room air as a source of tamponade, this is most effective in compliant patients with the causative break at 6-o’clock. The limited duration of tamponade with room air and the difficulty patients have inducing tamponade for breaks adjacent to 6-o’clock are factors in favor of expansile gases. In light of our experience with inverted pneumatic retinopexy and our observation of rapid subretinal fluid accumulation, I now routinely use room air for retinal detachments with causative breaks in the superior quandrants. Patients treated in a morning clinic (i.e., intravitreal injection of room air) are typically brought back at the end of the day for laser application. Although the technique of inverted pneumatic retinopexy is somewhat unorthodox and may not be appropriate for some patients, its proof of concept has tested several pathophysiologic paradigms and has expanded my understanding of pneumatic retinopexy in general. Most importantly, inverted pneumatic retinopexy provides an additional officebased treatment option for patients with inferior retinal detachments. TOM S. CHANG, MD Los Angeles, California
Dear Editor: Chang et al1 describe their success in treating retinal detachments associated with inferior retinal breaks and imply that pneumatic treatment of inferior retinal detachments “has not been previously described in the peer-reviewed literature.” However, unless one is absolutely certain of the total history of any new procedure, such claims often prove to be spurious or misleading, as it is here. Literature searches, particularly using online sources, can miss key references not in the databases used or not properly indexed. The reader of an article whose authors claim to be first to describe a procedure does not know for certain that an extensive literature search was conducted by the authors. Ironically, one of the key articles overlooked was published in Ophthalmology 15 years earlier. In an article entitled “Pneumatic Repair of Primary and Secondary Retinal Detachments Using a Binocular Indirect Ophthalmoscope La-
ser Delivery System”,2 Dr Eller and I described and illustrated with retinal drawings 22 cases of retinal detachment treated pneumatically after laser retinopexy, 20 of which were successfully repaired. For each of the 8 retinal detachments that had holes located in the inferior quadrants (between 4-o’clock and 8-o’clock), appropriate dependent positioning was performed. All of these eyes were successfully repaired pneumatically. Three years later, we also reported that, though many suggest that pneumatic retinopexy is successful only with breaks located in the superior 8 quadrants, “in our experience, some patients with inferior breaks may be managed with pneumatic retinopexy”.3 Finally, in the monograph Pneumatic Retinopexy: A Clinical Symposium,4 I also made the point that inferior retinal detachments with inferior breaks may be managed by pneumatic retinopexy. I am delighted to see that others are having success in using pneumatic retinopexy for inferior breaks. However, I suggest that if a journal article claims that something new is being described, the authors be compelled to reiterate what specific efforts were expended to back up such a claim, including details of the databases used. Certainly, it is much safer to state that “little attention has been given to” than to directly claim as these authors did that they were the first to describe, in the peer-reviewed literature, that pneumatic retinopexy can be applied for inferior retinal detachments. As you know with literature searches, there is no statistical parameter to guide the reader as to the validity of a firstto-publish claim. Many journals do not allow such claims to be made for this reason. This is in contrast to clinical research, where, if no difference is found between the outcomes of 2 procedures, the authors are usually compelled to state the power or certainty that no difference exists. THOMAS R. FRIBERG, MD Pittsburgh, Pennsylvania References 1. Chang TS, Pelzek CD, Nguyen RL, et al. Inverted pneumatic retinopexy. A method of treating retinal detachments associated with inferior retinal breaks. Ophthalmology 2003;110:589 –94. 2. Friberg TR, Eller AW. Pneumatic repair of primary and secondary retinal detachments using a binocular indirect ophthalmoscope laser delivery system. Ophthalmology 1988;95:187– 93. 3. Semin Ophthalmol 1991;6:27–35. 4. Tornambe PE, Grizzard WS, eds. Pneumatic Retinopexy: A Clinical Symposium. Des Plaines, IL: Greenwood Publishing; 1999:117–29.
Author reply Dear Editor: Dr Friberg appropriately points out an important error of omission in our article. After a review of the articles pointed out in his letter, I agree that ownership of the original idea began with his initial description in Friberg and Eller.1 This error of omission had occurred despite a careful electronic search for articles during preparation of the manuscript. After receiving Dr Friberg’s letter, I took the opportunity of repeating this MEDLINE search again using the National
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