Wall-Eyed Bilateral Internuclear Ophthalmoplegia in a Patient with Progressive Supranuclear Palsy

Abstract

Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) is a rare disorder consisting of a bilateral adduction deficit and primary gaze position exotropia. Associated with bilateral medial longitudinal fasciculus lesions, it has been mostly reported in patients with multiple sclerosis and brainstem stroke. A 72-year-old man with characteristic clinical features of progressive supranuclear palsy (PSP) later developed WEBINO. Brain MRI revealed atrophy of the midbrain tegmentum. Caloric irrigation revealed intact horizontal eye movements in both eyes. We believe this to be the first report of WEBINO in PSP. The preservation of vestibulo-ocular horizontal eye movements supports the notion that the WEBINO in this condition was caused by a supranuclear rather than a nuclear lesion and suggests the possibility that even in other causes of WEBINO, the lesion is supranuclear and not in the medial rectus subnucleus as is often suggested.

Transposition surgery for WEBINO

“…There is no single agreement about the features or causes of exotropia in WEBINO and only a few determined exotropia as an alternating XT with large magnitude but this is not true in all [6], as in our patient who has suffered from a [130D XT.…”

Bilateral thalamic stroke transiently reduces arousals and NREM sleep instability

“…This disorder may be caused by different conditions involving the brainstem, including vascular, inflammatory or neurodegenerative disorders [10]. Vertical gaze paresis is a common symptom in bilateral paramedian infarction and it is highly suggestive of the thalamo-subthalamic localization of the lesion [11].…”

A Case of Wall-Eyed Bilateral Internuclear Ophthalmoplegia (WEBINO) Syndrome Caused by Pontine Infarction

“…Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) syndrome is a bilateral internuclear ophthalmoplegia with alternating exotropia [1][2][3][4] . The pathogenesis of alternating exotropia in WEBINO syndrome is uncertain.…”

“…The pathogenesis of alternating exotropia in WEBINO syndrome is uncertain. Involvement of the bilateral medial longitudinal fasciculus (MLF) was considered to play a central role in the pathogenesis of WEBINO syndrome 1,2,[4][5][6] . Recently, hyperexcitation of the paramedian pontine reticular formation (PPRF) in addition to impairment of the MLF has been postulated in WEBINO syndrome 2,5,7) .…”

“…Recently, hyperexcitation of the paramedian pontine reticular formation (PPRF) in addition to impairment of the MLF has been postulated in WEBINO syndrome 2,5,7) . However, there have been few reports on study of the pathogenesis of WEBINO syndrome, based on the analysis of electronystagmogram (ENG) 1,5) .…”