Diplopia in Progressive Supranuclear Palsy

Abstract

We visited a 57-year-old man with horizontal diplopia. His problems had started 5 years earlier with progressive gait disturbance followed by falling backward, low-tone speech, and drooling. He was also suffering from binocular nonfluctuating diplopia since the previous year. Examination revealed bilateral exotropia on primary position with very slow saccadic movements. Vertical eye movements were severely limited. On horizontal movements, he had severe limited adduction of both eyes with nystagmus on the abducting eye. These abnormalities could be overcome by oculocephalic maneuver. The convergence was also impaired (Video S1). In addition, there was slowness of all movements and severe postural instability on the pull test (Video S2).Which of the following is a better explanation of eye movement abnormalities in this progressive supranuclear palsy (PSP) patient?A. Coincidental ocular myasthenia B. Coincidental internuclear ophthalmoplegia as a result of a structural lesion C. Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) as an ocular finding in PSP Answer C. WEBINO as an ocular finding in PSP. Parkinsonism with recurrent backward falls, vertical supranuclear gaze palsy, and a typical humming-bird sign on brain MRI (Supplementary Figure S1) are highly suggestive of PSP. Brain magnetic resonance imaging did not show any other structural lesion to explain the diplopia and abnormal eye movements. To rule out accompanying myasthenia, single-fiber electromyography and serum levels of antiacethylcholine receptor and anti-muscle specific tyrosine kinase antibodies were checked, and all of them were normal. We concluded that diplopia and abnormal horizontal eye movements in this case are compatible with WEBINO. WEBINO is a rare neurological syndrome characterized by exotropia in the primary gaze, limited adduction of the eyes, and convergence impairment. It is usually attributed to lesions of mesencephalic tegmentum involving medial longitudinal fasciculi or exaggerated excitation of both paramedian pontine reticular formation. [1][2][3] In addition to supranuclear gaze palsy, other eye movement abnormalities reported in PSP include lid retraction, square wave jerks, lid opening apraxia, and blepharospasm and rarely internuclear ophthalmoplegia and WEBINO. 1-3

Case report: A variant of wall-eyed bilateral internuclear ophthalmoplegia from unilateral pons infarction

“…Studies have shown that the disease is often associated with brainstem ischemia and hydrocephalus, immunotherapy of tumors, and diseases such as multiple sclerosis. This study summarized 39 case reports, including 42 WEBINO patients (Inocencio and Ballecer, 1985;Lana et al, 1990;Fay and Strominger, 1999;Korkmaz et al, 2002;Ozer et al, 2005;Chen and Lin, 2007;Kim et al, 2008;Matsumoto et al, 2008Matsumoto et al, , 2019Ushio et al, 2008;Jacob et al, 2010;Sierra-Hidalgo et al, 2010;Shinoda et al, 2011;Beh and Frohman, 2012;Jadhav and Prasad, 2012;Sakamoto et al, 2012;Bar et al, 2014;Chakravarthi et al, 2014;de Mora et al, 2014;Mathis et al, 2014;Muralidhar et al, 2014;Nakajima et al, 2014;Toufeeq and Dave, 2014;Agarwal et al, 2015;Ljevak et al, 2015;Man et al, 2015;de Souza et al, 2017;Sajjadi et al, 2017;Zou and Chen, 2017;Keereman et al, 2018;Papageorgiou et al, 2018;Im et al, 2020;Vázquez-Justes et al, 2020;Yazdi et al, 2020;Ansari et al, 2021;Jo et al, 2021;Petrik et al, 2021;Sinha et al, 2021;Wako et al, 2022). The age range of the ...…”