Bilateral Optic Disc Pits With Posterior Pituitary Ectopia

Photo Essay Section Editor: Timothy J. McCulley, MD Bilateral Optic Disc Pits With Posterior Pituitary Ectopia Jonathan C. Horton, MD, PhD, A. James Barkovich, MD FIG. 1. There is a pit located temporally in each optic disc. The arrows denote pigment surrounding each optic disc, which is organized into 2 distinct, concentric rings nasally. Ophthalmoscopy revealed a gap in the nerve fiber layer, which extended from each pit to the fovea. Abstract: Posterior pituitary ectopia has been reported previously in association with optic nerve hypoplasia, as a variant of septo-optic dysplasia. We describe a 14-year-old boy with posterior pituitary ectopia and bilateral optic disc pits. He had hypopituitarism and a reduction in visual acuity to 20/40 in each eye, owing to loss of foveal ganglion cells. Optic pits and posterior pituitary ectopia may have occurred together in the same subject by chance, but the rarity of both conditions suggests a possible association. Journal of Neuro-Ophthalmology 2017;37:401-402 doi: 10.1097/WNO.0000000000000528 © 2017 by North American Neuro-Ophthalmology Society a football game, followed by chronic headache. Amitriptyline was prescribed, and he was banned from all physical exertion including running. He was also being treated with levothyroxine, somatropin, and hydrocortisone for chronic pituitary insufficiency of unknown cause. On examination, the visual acuity was 20/40 in each eye with a refraction of plano in the right eye and 21.00 sphere in the left eye. The pupils were normal. He was too distractible to perform automated perimetry. There was a prominent gray optic pit at the temporal edge of each optic disc (Fig. 1). A subtle gap in the nerve fiber layer extending from each optic pit to the fovea was visible in each macula with an ophthalmoscope. There were A 14-year-old boy was brought to the eye clinic because of unexplained vision loss. For many years, he had lagged behind his peers in his school work. He received a diagnosis of attention deficit disorder and was treated with methylphenidate. Two years ago, a concussion occurred in Departments of Ophthalmology, Neurology, and Physiology (JCH), Beckman Vision Center, University of California San Francisco, San Francisco, California; and Department of Radiology (AJB), University of California San Francisco, San Francisco, California. Supported by National Eye Institute Grant EY10217, EY 02162, and Research to Prevent Blindness. The authors report no conflicts of interest. Address correspondence to Jonathan C. Horton, MD, PhD, 10 Koret Way, San Francisco, CA 94143; E-mail: [e-mail] Horton and Barkovich: J Neuro-Ophthalmol 2017; 37: 401-402 FIG. 2. Ganglion cell complex maps demonstrate a trough of reduced thickness (see scale in microns) extending from each fovea toward the optic pit. Red crosshairs mark patient's fixation, which was eccentric in each eye. 401 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Photo Essay FIG. 3. Brain magnetic resonance imaging. A. Sagittal fluid-attenuated inversion recovery image shows ectopic posterior lobe of the pituitary gland (arrow), and apparently absent anterior lobe. The corpus callosum and optic chiasm are slightly thin. B. Coronal T2 scan reveals small optic nerves (arrows). peripapillary pigment rings, a finding often associated with optic nerve pits (1). Optical coherence tomography (Optovue Avanti RTVUE XR, Fremont, CA) confirmed the presence of optic disc pits, with no subretinal fluid in the maculae. Analysis of the ganglion cell complex (nerve fiber layer, ganglion cell layer, and inner plexiform layer) revealed a distinct trough running from the optic pits to the fovea in each eye (Fig. 2). These defects in the ganglion cell complex were approximately 400 mm wide and 70 mm deep. The patient fixated eccentrically, presumably because the population of ganglion cells serving the fovea in each eye was reduced by the optic pits. Brain magnetic resonance imaging showed a slightly diminutive optic chiasm and corpus callosum (Fig. 3A). The most striking finding was the ectopic location of the posterior lobe of the pituitary gland, just beneath the optic chiasm. There was a shortened infundibulum, and the anterior lobe was not visible. The septum pellucidum was preserved. A coronal image through the orbits showed small optic nerves (Fig. 3B). Brodsky and Glasier (2) have described a variety of central nervous system abnormalities in association with optic nerve hypoplasia. In their report, 6 of 40 patients had absence of the pituitary infundibulum and posterior pituitary ectopia, with resulting hypopituitarism. The term "optoinfundibular hypoplasia" has been proposed for this variant of septo-optic dysplasia, although in fact, the septum pellucidum may be preserved (3). 402 The finding of bilateral optic nerve pits in a patient with posterior pituitary ectopia is unique. Our patient had no evidence of a serous maculopathy, but loss of foveal ganglion cells due to optic pits caused a reduction in acuity, bringing him to our attention. Optic nerve pits rarely are associated with central nervous system findings (4,5). It is possible that the pits and posterior pituitary ectopia in this child were unrelated, and occurred merely as a coincidence. Alternatively, their occurrence in the same individual could signify a real but rare association, adding to the remarkably diverse range of structural developmental anomalies encountered in patients with pituitary dysgenesis. REFERENCES 1. Slusher MM, Weaver RG Jr, Greven CM, Mundorf TK, Cashwell LF. The spectrum of cavitary optic disc anomalies in a family. Ophthalmology. 1989;96:342-347. 2. Brodsky MC, Glasier CM. Optic nerve hypoplasia. Clinical significance of associated central nervous system abnormalities on magnetic resonance imaging. Arch Ophthalmol. 1993;111:66-74. 3. Kaufman LM, Miller MT, Mafee MF. Magnetic resonance imaging of pituitary stalk hypoplasia. A discrete midline anomaly associated with endocrine abnormalities in septo-optic dysplasia. Arch Ophthalmol. 1989;107:1485-1489. 4. Heidary G. Congenital optic nerve anomalies and hereditary optic neuropathies. J Pediatr Genet. 2014;3:271-280. 5. Golnik KC. Cavitary anomalies of the optic disc: neurologic significance. Curr Neurol Neurosci Rep. 2008;8:409-413. Horton and Barkovich: J Neuro-Ophthalmol 2017; 37: 401-402 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited.