Scheimpflug imaging in a case of Aqueous Misdirection Syndrome Michael R. Gagnon, M.D. Valley EyeCare Center Clinical Instructor Stanford University School Of Medicine Maneesh H. Singh, B.S. Stanford University School Of Medicine We have no financial interests in the subject matter.*

Introduction Aqueous misdirection syndrome (malignant glaucoma) is a rare condition. It is characterized by a shallow axial anterior chamber (AC), a patent peripheral iridotomy and absence of suprachoroidal fluid. 1 To our knowledge we describe the first case of aqueous misdirection syndrome documented with Scheimpflug imaging (Pentacam HR:Oculus, Wetzlar, Germany).

Case Report An 88-year-old woman with prior history of bilateral cataract extraction 15 years ago presented to the emergency department with left eye pain and nausea and vomiting. Visual acuity was 20/25 OD and Count Fingers OS. Examination of the right eye revealed a deep AC and an intraocular pressure (IOP) of 18 mmHg. The left eye had corneal edema, a flat AC with iridocorneal touch, and an IOP of 66 mmHg. Gonioscopy revealed a wide-open angle in the right eye and 360 degrees of angle closure in the left eye. The posterior segment examination was normal with no evidence of choroidals.

Pentacam Scheimpflug image of anterior segment Right Eye Red arrow - Intraocular Lens Green arrows- Iris

Pentacam Scheimpflug image of anterior segment Left Eye Red arrow - Intraocular Lens Green arrows- Iris

Case Report Topical medications were started consisting of Combigan (brimonidine tartrate 0.2%/ timolol maleate 0.5%), brinzolamide 1%, prednisolone acetate1%, as well as oral acetazolamide 500 mg. Two neodymium:yttrium-aluminum-garnet (Nd:YAG) laser peripheral iridotomies were performed. The AC did not deepen but the IOP was controlled at 26 mmHg. The patient was discharged on Combigan twice daily, brinzolamide 1% twice daily, prednisolone acetate 1% four times daily, and acetazolamide 500 mg extended-release capsules every twelve hours.

Case Report The patient experienced eye pain as well as nausea and vomiting and presented the following morning. The IOP in the left eye was 40 mmHg and the AC was still flat despite two patent peripheral iridotomies. The diagnosis of aqueous misdirection was made and a Nd:YAG laser capsulotomy and hyaloidotomy was performed and was unsuccessful. Cycloplegia was started with topical atropine 1% four times daily and phenylephrine 2.5 % four times daily. The aqueous misdirection resolved with medical therapy after 2 days.The vision in the left eye was Hand Motions and the IOP was 6 mm Hg. The anterior chamber was deep (2.88 mm) and cornea was edematous with central pachymetry of 946 microns

Pentacam Scheimpflug image of anterior segment Left Eye Red arrow - Intraocular Lens Green arrows- Iris

Case Report The corneal edema slowly resolved over two months and the vision improved to 20/60 The patient was diagnosed with cystoid macular edema which resolved over four months with prednisolone 1% and bromfenac 0.09% and her vision improved to 20/20. She has been continued on atropine 1% once daily. Pentacam Scheimpflug image of anterior segment Left Eye

Discussion Aqueous misdirection syndrome is a rare type of secondary angle-closure glaucoma. It is poorly understood but thought to occur because of the diversion of aqueous behind the lens and anterior hyaloid and into the posterior segment with swelling of the vitreous and anterior rotation of the ciliary body processes. 2 Medical therapy includes topical mydriasis and cycloplegia, aqueous suppression, and hyperosmotic agents. 3 Surgical treatments include Nd:Yag laser posterior capsulotomy with hyaloidotomy, 4 argon laser ablation of the ciliary processes, 5 transscleral cyclodiode laser photocoagulation, 6 and surgical vitrectomy. 7

Conclusion This case demonstrates the utility of the Pentacam Scheimpflug imaging of the anterior chamber in aqueous misdirection syndrome. The Pentacam can be helpful in making the diagnosis of aqueous misdirection syndrome.

References 1. Sharma A, Sii F, Shah P, Kirkby G.R.Vitrectomy-phacoemulsification-vitrectomy for the management of aqueous misdirection syndromes in phakic eyes. Ophthalmology 2006;113(11): Tello C, Chi T, Shepps G, Liebmann J, Ritch R. Ultrasound biomicroscopy in pseudophakic malignant glaucoma. Ophthalmology 1993;100(9): Chandler PA, Grant WM. Mydriatic-cycloplegic treatment in malignant glaucoma. Arch Ophthalmol 1962; Lockie P. Ciliary-block glaucoma treated by posterior capsulotomy. Aust N Z J Ophthalmol 1987;15: Herschler J. Laser shrinkage of the ciliary processes: A treatment for malignant (ciliary block) glaucoma. Ophthalmology 87:1155, Stumpf TH, Austin M, Bloom PA, McNaught A, et al. Transscleral cyclodiode laser photocoagulation in the treatment of aqueous misdirection syndrome. Ophthalmology 2008;115: Lynch MG, Brown RH, Michels RG, et al. Surgical vitrectomy for pseudophakic malignant glaucoma. Am J Ophthal 1986;102: