A 52-year-old Canadian-born Japanese female presented with a 4-month history of decreased vision of the left eye (OS). Past history revealed calcific rotator tendinopathy, which required two barbotage treatments. Best corrected visual acuity (BCVA) was 20/20 in the right (OD) and 20/40 OS. Intraocular pressure was 20 mmHg OD and 22 mmHg OS. Slit-lamp examination revealed posterior chamber intraocular lens implants bilaterally. Dilated fundal examination of the right eye was unremarkable, but that of the left eye demonstrated foveal yellow-green intraretinal crystals (Figure 1) and mild vitritis. OCT of the left eye revealed small intraretinal fluid cysts and intraretinal hyper-reflective lesions in Henle's layer and inner nuclear layer, corresponding to the clinically observed crystals (Figure 2A,B,C). OCT of the right eye was normal. Ultra-widefield fluorescein angiography was normal in the right eye (Figure 3A), but that of the left eye showed disc leakage, petaloid macular edema, and diffuse peripheral retinal leakage (Figure 3B), consistent with intermediate uveitis. No peripheral retinal detachment, vascular telangiectasia, or retinal pigment epithelial abnormalities were observed in either eye.
There was no family history of African ancestry or a family history of crystalline maculopathy. There was no history of tamoxifen, canthaxanthine, methoxyflurane, and nitrofurantoin exposure; IV drug use; or kola nut consumption. She admitted to eating a diet high in oxalate (spinach, kale, chard). CT of the chest, purified protein derivative (PPD) test for tuberculosis, angiotensin-converting enzyme levels for sarcoidosis, FTA-ABS for syphilis, CBC, urinalysis, serum creatinine, ionized calcium, and 24-h urine oxalate were all normal.
The patient was treated with posterior subtenon triamcinolone (40 mg, Triesence, Alcon Laboratories, Inc., Fort Worth, TX, USA), with little improvement. The patient was then treated with intravitreal triamcinolone (4 mg, Triesence), and the intraretinal fluid subsequently resolved. BCVA improved to 20/30 OS, but the crystals remained.