Unusual presentation of angle-closure glaucoma treated by phacoemulsification

Abstract

We would like to comment on the case report by Wang and Lai.1 In any eye with a history of acute angle closure and persistent appositional angle closure despite a patent iridotomy, plateau iris syndrome is a common cause of elevated intraocular pressure (IOP), whether chronic or acute.2–8 Plateau iris syndrome is, in fact, not uncommon in Chinese eyes. An ultrasound biomicroscopic study of Chinese eyes with a history of acute angle closure and a patent iridotomy at our center revealed that 55.6% of the eyes had persistent appositional angle closure secondary to plateau iris configuration (unpublished data). In the presence of appositional angle closure secondary to plateau iris, argon laser peripheral iridoplasty (ALPI)9–11 can be considered. This technique has been effective in reopening the drainage angle, controlling IOP, and preventing recurrent acute attacks in plateau iris syndrome in the long term.12 We would like to know whether there were gonioscopic (eg, double-hump sign) or ultrasound biomicroscopic signs of plateau iris syndrome in this patient during the 9-year follow-up before the second acute attack. Argon laser peripheral iridotomy may, at least conceptually, also be effective in situations of appositional angle closure caused by other mechanisms such as angle crowding, although direct evidence is lacking. Merely observing an appositionally closed angle in an eye with previous acute angle closure and a patent iridotomy may result in recurrent acute angle closure (as evidenced by this case report) or progression to the chronic form of angle-closure glaucoma. Once the recurrent attack has occurred, ALPI may be the best treatment option to rapidly and safely control IOP and reopen the appositionally closed angle.13 We agree with the authors that lens extraction may have a beneficial effect in eyes with angle-closure glaucoma. However, the best timing for phacoemulsification in a patient with a recent acute angle closure has not been determined. It would be undesirable to perform phacoemusification if the eye were congested, the cornea edematous, and the pupil unable to be well dilated. Together with the shallow anterior chamber depth, the overall intraoperative risk will be higher. The patient can also be highly sensitized to pain, probably as a result of recent inflammation. Topical anesthesia may not be a good choice in such eyes. Excessive and exaggerated postoperative anterior chamber inflammation can occur, and intraoperative subconjunctival steroid injection would be helpful. We are interested to know whether the authors encounter similar difficulties during phacoemulsification and also whether there was significant anterior chamber reaction postoperatively. Safety is our primary concern when performing cataract extraction in an eye shortly after acute angle closure. The actual benefits and risks of early phacoemulsification in acute angle-closure eyes and the best timing for such interventions should be evaluated in a randomized controlled trial. Clement C.Y. Tham FRCS, FRCOphth(HK) Dexter Y.L. Leung FRCS Jimmy S.M. Lai MD, FRCOphth Dennis S.C. Lam MD, FRCOphth Hong Kong, China