Journal of Neuro-Ophthalmology, September 2012, Volume 32, Issue 3

Optic Disc Doubling

Many developmental defects can simulate the optic disc (optic disc pseudodoubling). True optic disc duplication with 2 independent retinal vasculatures is rare. Associated optic nerve duplication is rarer still and seen in lower vertebrates. We report a rare case of unilateral double optic discs with a single optic nerve in the left eye of a 41-year-old man, otherwise asymptomatic in the affected eye.

Optic Disc Doubling Tapas Ranjan Padhi, MS, Bikash Samal, BSc (Optom), Siddharth Kesarwani, MS, Soumyava Basu, MS, Taraprasad Das, FRCS FIG. 1. A. The left optic disc has an intact neuroretinal rim (C/D ratio = 0.5), but the inferotemporal venular trunk is absent. More inferiorly, there is a rudimentary optic disc and an area of retinal pigment epithelial atrophy that bridges the 2 discs. There is a single foveal avascular zone corresponding to the true optic disc at a level slightly lower than normal with a macular pigment epithelial detachment. The inferotemporal portion of the perifoveal capillary net is formed by tributaries from the superotemporal vascular arcade of the rudimentary disc. B and C. Fundus fluorescein angiogram of the left eye showing simultaneous and similar filling patterns of both the main and accessory vascular systems with pooling in the pigment epithelial detachment. D. Automated visual field of the left eye demonstrating an additional blind spot corresponding to the rudimentary disc with a contiguous arcuate scotoma superiorly. E. Optical coherence tomography line scan, passing obliquely across both optic discs, showing 2 craters of similar configuration but different depths. F. B-scan ultrasound of the left eye showing a single optic nerve shadow; a second optic nerve was not detected in additional planes. The patient declined orbital MRI. 238 Padhi et al: J Neuro-Ophthalmol 2012; 32: 238-239 Photo Essay Section Editor: Timothy J. McCulley, MD Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Abstract: Many developmental defects can simulate the optic disc (optic disc pseudodoubling). True optic disc duplication with 2 independent retinal vasculatures is rare. Associated optic nerve duplication is rarer still and seen in lower ver-tebrates. We report a rare case of unilateral double optic discs with a single optic nerve in the left eye of a 41-year-old man, otherwise asymptomatic in the affected eye. Journal of Neuro-Ophthalmology 2012;32:238-239 doi: 10.1097/WNO.0b013e3182464d9f © 2012 by North American Neuro-Ophthalmology Society Many developmental defects can simulate the optic disc (optic disc pseudodoubling) including peripapillary coloboma and scarring (1-3). True optic disc duplication with 2 independent retinal vasculatures is rare (4). We document such a case in the asymptomatic left eye of a 41-year-old man (Fig. 1). Visual acuity was 20/20 bilat-erally, and pupillary reactions were normal, as were anterior segment examinations and the right fundus appearance. The patient's general health was excellent, and medical history was unremarkable. REFERENCES 1. Islam N, Best J, Mehta JS, Sivakumar S, Plant GT, Hoyt WF. Optic disc duplication or coloboma? Br J Ophthalmol. 2005;89:26-29. 2. Young S, Ng JK, Gaynon MW. Pseudo duplication of the optic disk. Retinal Cases & Brief Reports. 2011;5:144-145. 3. Barboni P, Deluigi M, Bonis CD, Monetti G, Savini G, Zanini M. Pseudodoubling of the optic disc. Arch Ophthalmol. 1998;116:1400-1401. 4. Lamba PA. Doubling of the papillae. Acta Ophthalmologica. 1969;47:4-9. LV Prasad Eye Institute, Patia, Bhubaneswar, India. The authors report no conflicts of interest. Address correspondence to Tapas Ranjan Padhi, MS, Retina and Vitreous, LV Prasad Eye Institute, Bhubaneswar 751024, India; E-mail: [e-mail] Padhi et al: J Neuro-Ophthalmol 2012; 32: 238-239 239 Photo Essay Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited.