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Show Photo and Video Essay Section Editors: Kimberly M. Winges, MD Michael J. Gilhooley, MA, MB, BChir, DPhil Binasal Center-Involving Hemianopia of Presumed Congenital Etiology Ryan D. Larochelle, MD, Naresh Mandava, MD, Prem S. Subramanian, MD, PhD FIG. 1. Ocular coherence tomography of the optic nerves showing normal retinal nerve fiber layer thickness. A 25-year-old woman with a history of polysubstance abuse, depression, anxiety, and bipolar personality disorder was referred to our clinic for visual field loss of unknown etiology. She reported chronic difficulty with peripheral vision bilaterally, and she believed that both her peripheral and central vision worsened following a tubing accident in 2018. This accident caused traumatic Departments of Ophthalmology (RDL, NM, PSS), Neurology and Neurosurgery (PSS), Sue Anschutz-Rodgers University of Colorado Eye Center, University of Colorado School of Medicine, Aurora, Colorado; Division of Ophthalmology (PSS), Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, Maryland. Supported in part by an unrestricted grant to the Department of Ophthalmology, University Colorado School of Medicine, from Research to Prevent Blindness, Inc. The authors report no conflicts of interest. Address correspondence to Prem S. Subramanian, MD, PhD, Department of Ophthalmology, University of Colorado School of Medicine, 1675 Aurora Ct Mail Stop F731, Aurora, CO 80045; E-mail: prem.subramanian@cuanschutz.edu. e82 choroidal rupture in the right eye with no known longterm sequelae. She had a history of in utero exposure to alcohol and cocaine. She also reported chronic, episodic vision loss, poor coordination, headaches, and difficulty with concentration or sequential tasks. Visual acuity was 20/60 and 20/50 in the right and left eyes with no afferent pupillary defect and normal intraocular pressures. Ocular motility was somewhat limited in all directions bilaterally. Anterior eye examination was normal. Dilated fundus examination demonstrated nerves with 0.1 cup-to-disc ratio without pallor, edema, or drusen. The retinas were unremarkable except for a peripapillary scar from the prior choroidal rupture in the right eye. Optical coherence tomography (OCT) of the macula and fundus autofluorescence (FAF) imaging revealed no chorioretinal pathology. OCT of the retinal nerve fiber layer was unremarkable (Fig. 1). Automated visual field 24-2 testing had significant false-negatives but demonstrated a Larochelle et al: J Neuro-Ophthalmol 2023; 43: e82-e84 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Photo and Video Essay FIG. 2. Automated visual field 24-2 demonstrating nasal field defects encompassing the central vision in the left (A) and right (B) eyes. dense nasal field defect crossing the vertical meridian with a central scotoma in both eyes, with possible progression from prior studies obtained in 2018 (Fig. 2). On repeat testing, the pattern of the defect was unchanged. Kinetic visual field then confirmed nasal defects extending into the central vision (Fig. 3). Full-field electroretinography (ERG) was normal, and review of prior brain MRI showed no intracranial mass. Binasal visual field defects have been ascribed to various neurologic and ocular conditions. Early perimetric changes in glaucoma often include binasal defects, although the field loss typically progresses in an arcuate pattern on either side of the horizontal meridian because retinal ganglion fibers do not traverse the horizontal raphe. The Neurological Hemifield Test, which can help distinguish binasal field cuts of chiasmal or retrochiasmal etiology, excludes the most peripheral nasal field points to reduce the odds of misclassifying glaucoma as another neurologic disorder (1). Pituitary adenomas can produce binasal defects by displacing the anterior cerebral or internal carotid arteries against the lateral margins of the optic nerves (2). Primary empty sella syndrome has also been reported in association with binasal hemianopia or bilateral inferonasal quandrantanopia. One hypothesis is that the empty sella causes the chiasm to sit lower in the pituitary fossa, creating distance from the internal carotid arteries and potentially compromising perfusion of the lateral optic nerves and chiasm (3). The carotids can also impinge on the lateral optic nerves and produce binasal field cuts in the case of bilateral atherosclerosis or occlusions (4). While nonorganic disorders are a diagnosis of exclusion, functional loss can present with this pattern and can be definitively diagnosed using hemifield visual evoked potential (5). Despite the broad range of etiologies reported with binasal vision loss, true binasal hemianopia with complete hemifield loss respecting the vertical midline is quite rare. Other than the report by Charteris in a patient with an empty sella, binasal hemianopia has only been reported in 5 cases, all of which were presumed to be of congenital etiology due to no other identifiable causes (6–8). Scotcher hypothesized malformation of the temporal lateral geniculate nuclei. Bryan proposed a missorting syndrome in which temporal retinal ganglion cell axons do not reach the visual cortex; similar missorting patterns can be seen in achiasmatic syndrome and with the lack of decussation in albinism. Bryan noted that their patients’ asymptomatic presentation is similar to other patients with congenital field defects such as homonymous hemianopia and topless disc syndrome. The cause of our patient’s binasal, center-involving field defect remains uncertain. Her traumatic choroidal rupture was unilateral and did not develop a choroidal neovascular membrane. There are no findings on biomicroscopy, ERG, OCT, or FAF to suggest a retinal pathology. The optic nerves show no drusen, no pallor to suggest a toxic or mitochondrial etiology, no edema to suggest compression, and no cupping to suggest glaucoma. MRI demonstrated no intracranial mass compressing the lateral optic nerves or chiasm. Fetal alcohol syndrome may cause variable field changes from optic nerve hypoplasia and atrophy, but her optic nerves were normal. In light of FIG. 3. Kinetic visual field confirming center-involving nasal scotomas in the left (A) and right (B) eyes. Larochelle et al: J Neuro-Ophthalmol 2023; 43: e82-e84 e83 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Photo and Video Essay the normal workup to date, a congenital etiology remains the most likely diagnosis. STATEMENT OF AUTHORSHIP Conception and design: R. D. Larochelle, N. Mandava, P. S. Subramanian; Acquisition of data: R. D. Larochelle, N. Mandava, P. S. Subramanian; Analysis and interpretation of data: R. D. Larochelle, N. Mandava, P. S. Subramanian. Drafting the manuscript: R. D. Larochelle; Revising the manuscript for intellectual content: N. Mandava, P. S. Subramanian. Final approval of the completed manuscript: R. D. Larochelle, N. Mandava, P. S. Subramanian. REFERENCES 1. McCoy AN, Quigley HA, Wang J, Miller NR, Subramanian PS, Ramulu PY, Boland MV. Development and validation of an e84 improved neurological hemifield test to identify chiasmal and postchiasmal lesions by automated perimetry. Invest Ophthalmol Vis Sci. 2014;55:1017–1023. 2. Kawahigashi T, Nishiguchi S. Pituitary apoplexy with a binasal visual field defect. QJM. 2018;111:657–658. 3. Charteris DG, Cullen JF. Binasal field defects in primary empty sella syndrome. J Neuroophthalmol. 1996;16:110–114. 4. Hamann S, Obaid HG, Celiz PL. Binasal hemianopia due to bilateral internal carotid artery atherosclerosis. Acta Ophthalmol. 2015;93:486–487. 5. Moss HE, Jabbehdari S. Application of hemifield visual electrophysiology to diagnose functional vision loss. J Neuroophthalmol. 2020;40:527–529. 6. Pellegrini F, Interlandi E, Marullo M, Cirone D, Cuna A. Idiopathic binasal hemianopia: case report and literature review. Eur J Ophthalmol. 2021:31;NP26–NP30, 7. Scotcher S, Morphis G, Good P. Binasal hemianopia in two sisters. BMJ Case Rep. 2020;13:e232486. 8. Bryan BT, Pomeranz HD, Smith KH. Complete binasal hemianopia. Proc (Bayl Univ Med Cent). 2014;27: 356–358. Larochelle et al: J Neuro-Ophthalmol 2023; 43: e82-e84 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. |