Slitlamp photograph of argon laser peripheral iridoplasty applications.
Zalta AH, Smith RT. Peripheral Iridoplasty Efficacy in Refractory Topiramate-Associated Bilateral Acute Angle-Closure Glaucoma. Arch Ophthalmol. 2008;126(11):1603-1605. doi:10.1001/archopht.126.11.1603
Simultaneous bilateral acute angle-closure glaucoma (BAACG) is a rare1 and potentially blinding disease. From 20012 through 2007,3 there have been about 100 reports1- 4 of topiramate-associated secondary BAACG, establishing topiramate as a leading cause of this condition in patients younger than 40 years. In 83 cases of bilateral and 3 cases of unilateral topiramate-associated acute secondary angle-closure glaucoma, 7 patients sustained permanent vision loss.4 Topiramate (Topamax; Ortho-McNeil Neurologics, Titusville, New Jersey)5 was approved by the Food and Drug Administration to prevent seizures in 1996 and migraine headaches in 2004, but it is also being used off-label for depression and bipolar disorders, neuropathic pain, and weight reduction.4 In 2001, a warning was added to the package insert describing a rare syndrome consisting of ciliochoroidal effusion, forward displacement of the lens-iris diaphragm, marked anterior chamber shallowing, acute myopia, and secondary angle-closure glaucoma.1 This process is usually reversible if topiramate is discontinued and ocular hypotensive therapy is instituted.4 In eyes unresponsive to these measures, there are no definitive treatment recommendations to avoid high-risk fistulizing surgery. Because pupillary block is not present in topiramate-associated BAACG, peripheral iridectomy is ineffective.4
We describe 4 patients (8 eyes) who were effectively treated with argon laser peripheral iridoplasty (ALPI) for topiramate-associated BAACG unresponsive to ocular hypotensive therapy and topiramate discontinuation. To our knowledge and according to a MEDLINE literature review performed in March 2008, there are no published reports on the use of ALPI for this condition.
Table 1 and Table 2 contain patient demographics, rationale and duration of topiramate treatment, clinical parameters of topiramate-associated BAACG before and after ocular hypotensive therapy, peripheral iridoplasty treatment and effect, and clinical parameters of topiramate-associated BAACG after peripheral iridoplasty. Because bilateral complete angle closure developed and persisted in 4 white women despite medical therapy and topiramate discontinuation, ALPI (300- or 500-μm spot size, 0.5-second duration, 200- to 400-mW power range) was performed (by A.H.Z.) in all of the 8 eyes (Figure). Within 30 minutes of ALPI, the intraocular pressure was markedly reduced and the peripheral anterior chamber had significantly deepened in all of the eyes. In an effort to prevent a subsequent pupillary block, all of the eyes underwent a laser iridotomy later the same day. Five months after iridoplasty, the intraocular pressure was normal in all of the eyes in the absence of ocular medications; only 4 eyes had mild, residual peripheral anterior synechiae.
Argon laser peripheral iridoplasty is a relatively easy, safe, and effective treatment for refractory topiramate-associated BAACG. To our knowledge, this case series represents the first report describing the use of ALPI for this condition. The ALPI technique is a well-recognized procedure used to treat angle closure from mechanisms other than pupillary block.6 Although this report is limited by its small sample size and lack of a control eye, refractory topiramate-associated BAACG should be added to the list of indications for ALPI.
A unique finding in this case series was progressive central anterior chamber shallowing even after ALPI eliminated appositional angle closure. While the mechanism is unclear, we believe that the topiramate-associated BAACG occurred before maximum development of the ciliochoroidal effusions. Because of this consideration and the unpredictable effects of miotics and cycloplegics, laser iridotomy was performed after ALPI as a simple, low-risk, precautionary measure to prevent subsequent pupillary block. While laser iridotomy may have been an unnecessary procedure, recurrent angle closure did not occur in any eye.
Whenever BAACG occurs with acute myopia in patients younger than 40 years, topiramate-associated ciliochoroidal effusion syndrome should be strongly suspected. Because topiramate has a growing list of approved and off-label uses, ophthalmologists should anticipate an increasing number of topiramate-associated BAACG cases and perform ALPI if discontinuation of topiramate and ocular hypotensive therapy fail to reverse this sight-threatening disease.
Correspondence: Dr Zalta, University of Cincinnati College of Medicine, University Medical Arts Bldg, 222 Piedmont Ave, Ste 1700, Cincinnati, OH 45219 (firstname.lastname@example.org).
Author Contributions: Dr Zalta had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Financial Disclosure: None reported.