WHAT’S YOUR DIAGNOSIS? MORNING ROUNDS

The Strange Case of a Triangular

n April 1, 2015, Theresa Tip- 1A 1B pet* was vacationing in Flor- Oida with her husband. While relaxing on the beach, the 24-year-old accidentally rubbed sand into her . Initially, she did not think much of it. However, at a family gathering 1 week later, her husband noticed that her pupil was now shaped like a teardrop, and they couldn’t help but fear that something insidious was occurring. AT THE SLIT LAMP. (1A) Right pupil appears triangular in light. Left pupil was normal. There is no heterochromia. (1B) Posterior has a “beaten bronze” The Presentation appearance. When Ms. Tippet presented to our neuro-ophthalmology clinic, she had The Exam Adie’s tonic pupil was ruled out. no relevant medical history. She and On initial exam, we could appreciate and trauma were still possible, but— her husband were concerned that her the irregularity of her right pupil in given her history—seemed unlikely. misshapen pupil might be the result of light, but her pupillary constriction was a brain tumor. An outside ophthalmol- brisk with minimal anisocoria. In dark- Tests and Final Diagnosis ogist thought that her pupil might be ness, her right pupil was 7.5 mm and OCT anterior segment imaging was related to migraines, though she had no her left pupil was 7.0, and constriction performed to document her anterior complaints of visual changes or head- to light and convergence were brisk synechiae (Fig. 2A). The image also ache. She also denied any history of red in both . Her intraocular pressure showed formation of a distinct mem- eye, eye infection, eye surgery, and eye (IOP) was 15 mm Hg in both eyes. brane over the stroma. On confocal trauma, other than the aforementioned Slit-lamp biomicroscopy showed microscopy, Ms. Tippet had swollen- incident at the beach. Of note, her eye high peripheral anterior synechiae appearing endothelial cells with irreg- required irrigation to remove the sand, (PAS) with iris tenting at 1, 5, and 9 ular borders, as well as a moderately but she denied having pain following o’clock. This unique distribution pulled decreased cell count in comparison the event. She also denied photophobia, her pupil into a triangular shape with to her left eye. Her endothelial cells but stated that “she felt a slight twinge constriction (Fig. 1A). She also had a had prominent nuclei (Fig. 2B). These of pain” when moving from darkness to “beaten bronze” appearance of her pos- findings were typical of, and helped to light. Her husband was certain that her terior cornea (Fig. 1B). We did not find confirm a diagnosis of, iridocorneal pupil had been normal prior to April. any stretch holes, iris transillumination endothelial (ICE) syndrome. Based on history alone, we initially defects, cell and flare, or corneal edema. suspected Adie’s tonic pupil, but we Gonioscopy confirmed our findings. Pathogenesis were also considering iridocyclitis and Her posterior exam was unremarkable. ICE syndrome is a sporadic disease trauma in our differential diagnosis. Following the exam, the diagnosis of characterized by inappropriate pro- liferation of the corneal endothelium. Though the exact mechanism is not BY MATTHEW SNIDER AND SANGEETA KHANNA, MD. EDITED BY STEVEN J. well understood, it is thought that the

Saint Louis University Eye Institute. Eye University Saint Louis GEDDE, MD. endothelial cells, which are normally

EYENET MAGAZINE • 39 2A 2B 2C

locked in the G1 phase of the cell cycle, FURTHER CLUES. (2A) On anterior OCT, we noted high PAS with membrane pull- are able to proliferate and grow onto ing on iris and abnormal endothelial cell layer on iris. (2B) On confocal microscopy, the iris. This causes diffuse PAS, as well we observed endothelial cells with irregular borders and prominent nuclei in the as damage to the iris. The cells are said right eye and (2C) normal endothelial cell appearance in the left. to behave and appear more like epithe- lial cells. There is some evidence to sug- Differential Diagnosis particularly difficult to manage and gest that the disease may be related to Diagnosis can be challenging and will often requires surgical treatment. While herpes simplex virus (HSV) infection, vary based on the presentation. This medical management with aqueous though the association is not certain.1,2 disease is most often confused with production suppressants is a reason- It is possible that inflammation from a posterior polymorphous dystrophy, able choice to decrease IOP as well as virus may promote abnormal epitheli- which is more often bilateral and corneal edema, these patients will often al-like behavior of the endothelial cells, familial. For this reason, lack of family require a shunting procedure or trabe- causing migration onto the trabecular history can be a useful clue when differ- culectomy to help control IOP. Because meshwork and the iris. There is no entiating between these 2 diseases. the endothelial cells will continue to current research on whether treatment Another common misdiagnosis grow abnormally, failure rate for sur- for HSV might help the long-term occurs when ICE is confused with uni- gery is high, and the need for further prognosis of ICE. lateral primary open-angle . procedures should be anticipated. This misdiagnosis could be particularly Similarly, many patients with corne- Typical Presentations easy to make in a case like ours, which al edema will ultimately require corneal This rare disease typically presents uni- has a paucity of symptoms. Of course, transplantation. Penetrating keratoplas- laterally, though occasionally bilaterally, our case lacked elevated IOP. ty and endothelial keratoplasty are the in women in their 20s to 40s. The differential diagnosis is highly 2 most common procedures on these There are 3 variants described in the dependent on the variant and exam patients. literature, and though there is consider- findings. For example, in a case with Finally, it is important to stress that able overlap between them, each has a the predominant feature of peduncu- prognosis is highly variable and case hallmark trait that predominates: lated iris nodules, neurofibromatosis dependent. • Chandler syndrome is the most would be high on the differential; how- common variant, and its hallmark is ever, in a patient presenting primarily Our Patient corneal edema. with corneal edema, Fuchs endothelial Ms. Tipper was advised to follow up • Essential iris atrophy’s hallmark is dystrophy would be placed higher on with her primary ophthalmologist large stretch holes and irregularities of the differential. Because of the broad every 6 months to monitor IOP. We the iris. differential, confocal microscopy is a also discussed the questionable role of • Cogan-Reese syndrome’s hallmark is useful tool to help differentiate between antivirals in this disease and she chose pigmented, pedunculated iris masses; other etiologies on the basis of the observation at this time. Cogan-Reese is the least common of features described above. the variants. * Patient name is fictitious. Other characteristics that may occur Complications and 1 Alvarado JA et al. Arch Ophthalmol. 1994; in any of the variants include increased Management 112(12):1601-1609. IOP, “beaten bronze” appearance of Unfortunately, there is no cure for ICE 2 Sacchetti M et al. Biomed Res Int. 2015;2005: endothelium, and diffuse PAS. syndrome. The most serious complica- 763093. doi:10.1155/2015/763093. Confocal or specular microscopy tions of ICE are glaucoma and corneal is particularly useful in diagnosis. On edema. For this reason, these patients Dr. Khanna is an assistant professor of ophthal- confocal microscopy, look for light to must have lifelong, regular visits to an mology and Matthew Snider is a fourth-year dark inversion, prominent endothelial ophthalmologist for monitoring of medical student; both are at the Saint Louis nuclei, decreased endothelial cell count, disease progression. University School of Medicine, St. Louis, Mo.

and irregular endothelial borders. In these patients, glaucoma can be They report no financial disclosures. Institute. Eye University Saint Louis

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