Isolated or predominant ocular motor nerve palsy as a manifestation of brain stem stroke.

Abstract

Background and Purpose: There have been few reports of strokes producing isolated or predominant ocular motor nerve palsies as a clinical manifestation.Methods: We studied seven patients with brain stem stroke who had ocular motor palsies as the only or the predominant neurological manifestation, and we correlated their clinical features with radiological findings.Results: Five patients had small strokes in the area of oculomotor nuclei or fascicles and showed various combinations of oculomotor disturbances. Three of these patients showed vertical gaze paresis of the opposite eye. One patient with a small hemorrhage near the aqueduct of Sylvius showed fourth nerve palsy on the contralateral side, and a patient with a small infarct in the pontine tegmentum showed isolated sixth nerve palsy. Nonocular minor neurological signs included trigeminal sensory changes in four patients and clumsy arm in two. Ocular and nonocular dysfunctions generally improved within several months. Radiological findings of the brain stem correlated well with the ocular signs.Conclusions: We conclude that acute brain stem stroke should be included in the differential diagnosis of isolated ocular motor nerve palsies and that appropriate diagnostic investigations should be performed in these cases.

Cerebrovascular Brainstem Diseases with Isolated Cranial Nerve Palsies

“…Isolated cranial nerve palsies, most commonly of the 3rd and 6th and less frequently of the 4th, 5th, 7th, and 8th nerves, have been observed in an increasing number of patients as the sole manifestation of cerebrovascular brainstem diseases, mainly infarctions [14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42]and less frequently hemorrhages [43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56]. This seems to be an underestimated and important cause of isolated cranial nerve palsies, as a considerable number still escapes ‘routine’ MRI (i.e.…”

“…Based on these observations, it seems justified to classify brainstem infarctions into three main categories: (1) infarctions involving the intra-axial cranial nerve segments and long tracts (the ‘classic’ ischemic brainstem syndromes) [1, 2, 3]; (2) infarctions involving long tracts and sparing intra-axial cranial nerve segments (the lacunar brainstem syndromes) [4, 5], and (3) small infarctions involving intra-axial cranial nerve segments and sparing long tracts, i.e. isolated cranial nerve palsies due to brainstem lesions (‘cranial nerve brainstem syndromes’) [14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42]. …”

“…Moreover, the anatomy of the brainstem vasculature was thought unable to explain an intra-axial cranial nerve ischemia with sparing of surrounding structures [13]. There is, however, an increasing number of individual patients with palsies of the 3rd–8th cranial nerves as the sole manifestation of small MRI (or CT)-documented brainstem infarctions or hemorrhages (table 1) [14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56]. These reports and several electrophysiologic studies [27, 41, 42, 57]suggest that a significant number of isolated palsies of the 3rd–8th cranial nerves are on the basis of vascular lesions of the midbrain and pons, which may be the most common cause of 3rd and 6th nerve palsies in middle-aged and elderly people.…”

Combined Peripheral Facial and Abducens Nerve Palsy Caused by Caudal Tegmental Pontine Infarction

“…It is known that tiny pontine lesions can cause isolated peripheral facial [2, 3]or abducens palsy [4, 5, 6, 7]; combined paralysis of the facial and abducens nerve without other neurologic signs seems, however, to occur less than peripheral facial or abducens palsy in isolation, because the two fascicles run close to each other for too short a distance. It appears, though, that our case 1 has a lesion which involves both the facial and abducens nerve fascicle but does not damage other surrounding structures.…”

The "one-and-a-half" syndrome: case report

“…Lesions of the MLF do not cause paralysis of conjugate horizontal or vertical gaze 7 . Upgaze palsy, downgaze palsy, complete vertical gaze palsy and vertical saccade for both upward and downward gaze have been known to be related to bilateral lesions involving the rostral interstitial nucleus of medial longitudinal fasciculus (RiMLF) cell group and the posterior commissure 5,13 . Gordon and Bender 11 described rare forms of visual symptoms due to lesions of the MLF such as monocular diplopia, oscillopsia and diplopia with oscillopsia of only one of two images, usually the false, while the true image remains stationary.…”