Correspondence
Vol. 114, No. 3
owski, Nesher and Kolker6·7 described a pa tient, treated prophylactically with apraclonidine, who had no significant increased pres sure one hour after procedure, but had a significant increase one day later. We concur with previous suggestions that patients with severe glaucomatous damage be seen not only immediately after laser treatment, but also 24 hours later.6 Dr. Romanowski's comments al low us to expand on the interpretation of our report. DAVID E. SILVERSTONE, M.D. New Haven, Connecticut STEPHEN F. BRINT, M.D. New Orleans, Louisiana KENNETH W. OLANDER, M.D. Milwaukee, Wisconsin ROBERT B. TAYLOR GEORGE R. McCARTY, Ph.D. JOSEPH M. deFALLER Fort Worth, Texas LINDA L. BURK, M.D. Dallas, Texas
References 1. Channell, M. M., and Beckman, H.: Intraocular pressure changes after neodymium-YAG laser poster ior capsulotomy. Arch Ophthalmol. 102:1024, 1984. 2. Richter, C. U., Arzeno, G., Pappas, H. R„ Arrigg, C. A., Wasson, P., and Steinert, R. F.: Preven tion of intraocular pressure elevation following neo dymium-YAG laser posterior capsulotomy. Arch. Ophthalmol. 103:912, 1985. 3. Silverstone, D. E., Novack, G. D., Kelley, E. P., and Chen, K. S.: Prophylactic treatment of intraocu lar pressure elevations after neodymium:YAG laser posterior capsulotomies and extracapsular cataract extractions with levobunolol. Ophthalmology 95:713, 1988. 4. Jampel, H. D., Robin, A. L., Quigley, H. A., and Pollack, I. P.: Apraclonidine. A one-week dose-re sponse study. Arch Ophthalmol. 106:1069, 1988. 5. Vocci, M. J., Robin, A. L., Wahl, J. C , Mayer, P., Graves, A., York, B., Enger, C , and Sutton, J.: Apra clonidine hydrochloride. An evaluation of reformula tion and drop size. Am. J. Ophthalmol. 113:154, 1992. 6. Nesher, R., and Kolker, A. E.: Delayed increased intraocular pressure after Nd:YAG laser posterior capsulotomy in a patient treated with apraclonidine. Am. J. Ophthalmol. 110:94, 1990. 7. : Failure of apraclonidine to prevent de layed IOP elevation after Nd:YAG laser posterior capsulotomy. Trans. Am. Ophthalmol. Soc. 88:229, 1990. 8. Wiles, S. B., MacKenzie, M. D., and Ide, C. H.:
379
Control of intraocular pressure with apraclonidine hydrochloride after cataract extraction. Am. J. Oph thalmol. 111:184, 1991.
Argon Laser Treatment of Trichiasis EDITOR: The article, "Argon laser treatment of trichi asis," by G. B. Bartley and J. C. Lowry (Am. J. Ophthalmol. 113:71, January 1992), reported a recurrence rate of 4 1 % in a retrospective study of 44 patients treated by argon laser. Laser variables included 1.10-W power, 50- to 100ìðé spot size, 0.2-second duration, and bluegreen wavelength. The depth of vaporization was not mentioned. In a recent prospective study of 60 patients, 1 a recurrence rate of 11.6% was reported. Laser variables were 1.5-W power, 100-ìðé spot size, and 0.5-second duration. Vaporization was car ried out to a depth of 2.0 to 2.5 mm in a plane just superior to the postorbicular fascia. Recurrences were most often caused by inad equate depth of vaporization and less fre quently by unpredictable follicle position (for example, posttraumatic lash malposition). We believe a depth gauge is helpful in assuring adequate laser treatment, and its routine use may improve treatment outcome and reproducibility. Finally, we have modified our tech nique and now use the laser in the continuous mode at a power of 2.5 W. This change per mits more rapid lash ablation (six to ten puls es) and limits contiguous vaporization. A re currence rate of 11.6% compares favorably to cryoablation. 2 We agree with the authors that laser ablation is best suited to isolated, aber rant cilia. M. DOUGLAS GOSSMAN, M.D. RUDY YUNG, M.D. A. JAN BERLIN, M.D. JOSEPH R. BRIGHTWELL, M.D. JOHN W. WILLIAMS, M.D. Louisville, Kentucky
References 1. Gossman, M. D., Yung, R., Berlin, A. J., and Brightwell, J. R.: Prospective evaluation of the argon laser in the treatment of trichiasis. Ophthalmic Surg. 23:183, 1992.
380
September, 1992
AMERICAN JOURNAL OF OPHTHALMOLOGY
2. Sullivan, J. H., Beard, C and Bullock, J. D.: Cryosurgery for the treatment of trichiasis. Am. J. Ophthalmol. 82:117, 1976. Reply EDITOR: The criterion we used for successful treat ment was unequivocal ablation of treated cilia in an eyelid. Therapy was judged to have failed if any aberrant eyelashes subsequently appeared, even if a misdirected cilium may have represented new rather than recurrent tri chiasis. We agree with Dr. Gossman and associates that most recurrences result from inadequate depth or intensity of laser treatment. The depth of the laser burns in the patients we treated was approximately 2 to 3 mm but the power, spot size, and duration of each pulse were less than that used by Dr. Gossman and colleagues. 1 In another recent report in which more conservative laser parameters were used (0.3 W, 0.5-second duration, 50-ìðé spot size, and 40 to 50 burns per eyelash), secondary treatment was necessary in 29 of 77 patients (38%).2 Since we reviewed our results, we have used a larger spot size (100 ìçá) and an increased number of burns (up to 50 per follicle). An additional feature of the technique described by Dr. Gossman and associates that may pro mote eyelash ablation is to deliver several defocused, 200-ìéç burns to the base of the folli cle. In appropriately selected patients, more intensive treatment appears to improve success
without increasing the frequency of complica tions. Dr. Gossman and colleagues should be congratulated on their excellent therapeutic re sults. GEORGE B. BARTLEY, M.D. JONATHAN C. LOWRY, M.D. Rochester, Minnesota
References 1. Gossman, M. D., Yung, R., Berlin, A. J., and Brightwell, J. R.: Prospective evaluation of the argon laser in the treatment of trichiasis. Ophthalmic Surg. 23:183, 1992. 2. Huneke, J. W.: Argon laser treatment for trichia sis. Ophthalmic Plast. Reconstr. Surg. 8:50, 1992.
Sculpting of Hydroxyapatite Implants—Correction EDITOR: In the article, "Sculpting of hydroxyapa tite implants" (Am. J. Ophthalmol. 113:453, 1992), I mentioned in the text that the caliper used for sculpting was a Green caliper. I have since learned that the correct name is a Jame son caliper. I regret this mistake, and thought I should bring it to the attention of readers of THE JOURNAL.
MONT J. CARTWRIGHT, M.D. Ann Arbor, Michigan
Vol. 114, No. 3
owski, Nesher and Kolker6·7 described a pa tient, treated prophylactically with apraclonidine, who had no significant increased pres sure one hour after procedure, but had a significant increase one day later. We concur with previous suggestions that patients with severe glaucomatous damage be seen not only immediately after laser treatment, but also 24 hours later.6 Dr. Romanowski's comments al low us to expand on the interpretation of our report. DAVID E. SILVERSTONE, M.D. New Haven, Connecticut STEPHEN F. BRINT, M.D. New Orleans, Louisiana KENNETH W. OLANDER, M.D. Milwaukee, Wisconsin ROBERT B. TAYLOR GEORGE R. McCARTY, Ph.D. JOSEPH M. deFALLER Fort Worth, Texas LINDA L. BURK, M.D. Dallas, Texas
References 1. Channell, M. M., and Beckman, H.: Intraocular pressure changes after neodymium-YAG laser poster ior capsulotomy. Arch Ophthalmol. 102:1024, 1984. 2. Richter, C. U., Arzeno, G., Pappas, H. R„ Arrigg, C. A., Wasson, P., and Steinert, R. F.: Preven tion of intraocular pressure elevation following neo dymium-YAG laser posterior capsulotomy. Arch. Ophthalmol. 103:912, 1985. 3. Silverstone, D. E., Novack, G. D., Kelley, E. P., and Chen, K. S.: Prophylactic treatment of intraocu lar pressure elevations after neodymium:YAG laser posterior capsulotomies and extracapsular cataract extractions with levobunolol. Ophthalmology 95:713, 1988. 4. Jampel, H. D., Robin, A. L., Quigley, H. A., and Pollack, I. P.: Apraclonidine. A one-week dose-re sponse study. Arch Ophthalmol. 106:1069, 1988. 5. Vocci, M. J., Robin, A. L., Wahl, J. C , Mayer, P., Graves, A., York, B., Enger, C , and Sutton, J.: Apra clonidine hydrochloride. An evaluation of reformula tion and drop size. Am. J. Ophthalmol. 113:154, 1992. 6. Nesher, R., and Kolker, A. E.: Delayed increased intraocular pressure after Nd:YAG laser posterior capsulotomy in a patient treated with apraclonidine. Am. J. Ophthalmol. 110:94, 1990. 7. : Failure of apraclonidine to prevent de layed IOP elevation after Nd:YAG laser posterior capsulotomy. Trans. Am. Ophthalmol. Soc. 88:229, 1990. 8. Wiles, S. B., MacKenzie, M. D., and Ide, C. H.:
379
Control of intraocular pressure with apraclonidine hydrochloride after cataract extraction. Am. J. Oph thalmol. 111:184, 1991.
Argon Laser Treatment of Trichiasis EDITOR: The article, "Argon laser treatment of trichi asis," by G. B. Bartley and J. C. Lowry (Am. J. Ophthalmol. 113:71, January 1992), reported a recurrence rate of 4 1 % in a retrospective study of 44 patients treated by argon laser. Laser variables included 1.10-W power, 50- to 100ìðé spot size, 0.2-second duration, and bluegreen wavelength. The depth of vaporization was not mentioned. In a recent prospective study of 60 patients, 1 a recurrence rate of 11.6% was reported. Laser variables were 1.5-W power, 100-ìðé spot size, and 0.5-second duration. Vaporization was car ried out to a depth of 2.0 to 2.5 mm in a plane just superior to the postorbicular fascia. Recurrences were most often caused by inad equate depth of vaporization and less fre quently by unpredictable follicle position (for example, posttraumatic lash malposition). We believe a depth gauge is helpful in assuring adequate laser treatment, and its routine use may improve treatment outcome and reproducibility. Finally, we have modified our tech nique and now use the laser in the continuous mode at a power of 2.5 W. This change per mits more rapid lash ablation (six to ten puls es) and limits contiguous vaporization. A re currence rate of 11.6% compares favorably to cryoablation. 2 We agree with the authors that laser ablation is best suited to isolated, aber rant cilia. M. DOUGLAS GOSSMAN, M.D. RUDY YUNG, M.D. A. JAN BERLIN, M.D. JOSEPH R. BRIGHTWELL, M.D. JOHN W. WILLIAMS, M.D. Louisville, Kentucky
References 1. Gossman, M. D., Yung, R., Berlin, A. J., and Brightwell, J. R.: Prospective evaluation of the argon laser in the treatment of trichiasis. Ophthalmic Surg. 23:183, 1992.
380
September, 1992
AMERICAN JOURNAL OF OPHTHALMOLOGY
2. Sullivan, J. H., Beard, C and Bullock, J. D.: Cryosurgery for the treatment of trichiasis. Am. J. Ophthalmol. 82:117, 1976. Reply EDITOR: The criterion we used for successful treat ment was unequivocal ablation of treated cilia in an eyelid. Therapy was judged to have failed if any aberrant eyelashes subsequently appeared, even if a misdirected cilium may have represented new rather than recurrent tri chiasis. We agree with Dr. Gossman and associates that most recurrences result from inadequate depth or intensity of laser treatment. The depth of the laser burns in the patients we treated was approximately 2 to 3 mm but the power, spot size, and duration of each pulse were less than that used by Dr. Gossman and colleagues. 1 In another recent report in which more conservative laser parameters were used (0.3 W, 0.5-second duration, 50-ìðé spot size, and 40 to 50 burns per eyelash), secondary treatment was necessary in 29 of 77 patients (38%).2 Since we reviewed our results, we have used a larger spot size (100 ìçá) and an increased number of burns (up to 50 per follicle). An additional feature of the technique described by Dr. Gossman and associates that may pro mote eyelash ablation is to deliver several defocused, 200-ìéç burns to the base of the folli cle. In appropriately selected patients, more intensive treatment appears to improve success
without increasing the frequency of complica tions. Dr. Gossman and colleagues should be congratulated on their excellent therapeutic re sults. GEORGE B. BARTLEY, M.D. JONATHAN C. LOWRY, M.D. Rochester, Minnesota
References 1. Gossman, M. D., Yung, R., Berlin, A. J., and Brightwell, J. R.: Prospective evaluation of the argon laser in the treatment of trichiasis. Ophthalmic Surg. 23:183, 1992. 2. Huneke, J. W.: Argon laser treatment for trichia sis. Ophthalmic Plast. Reconstr. Surg. 8:50, 1992.
Sculpting of Hydroxyapatite Implants—Correction EDITOR: In the article, "Sculpting of hydroxyapa tite implants" (Am. J. Ophthalmol. 113:453, 1992), I mentioned in the text that the caliper used for sculpting was a Green caliper. I have since learned that the correct name is a Jame son caliper. I regret this mistake, and thought I should bring it to the attention of readers of THE JOURNAL.
MONT J. CARTWRIGHT, M.D. Ann Arbor, Michigan
