Lateral Gaze Disturbance in a Case of Wallenberg’s Syndrome

Abstract

A 63-year-old Caucasian man was admitted for Wallenberg’s syndrome following a left vertebral artery thrombosis. In addition to the classical symptoms, an axial lateropulsion to the left and ocular motor disorders (vertical diplopia, tonic deviation of the gaze to the left, skew deviation and horizonto-rotatory nystagmus) were present. These clinical signs are unusual, but in common Wallenberg’s syndrome, neurophysiological tests often reveal slight abnormalities of oculomotor function: impairment of jerks, skew deviation, lateral deviation of the gaze in darkness. Interruption of cerebellar pathways is thought to be the cause of these symptoms. Their existence does not seem to change the outcome of these cases.

Clinical Differences between Radiographic and Physical Horizontal Gaze Deviation: Utility of Using the Two in Patients with Ischemic Stroke

“…Lesions in the lateral medulla were reported to cause PHGD and/or RHGD directed to the ipsilesional side. 9,27 These ipsilesional HGDs are probably caused by decreased activity of the ipsilesional medial vestibular nucleus (MVN), which is resulted from ischemia of the MVN or climbing fibers from the contralateral inferior olivary nucleus. 28 The MVN normally excites the contralateral abducens nucleus and inhibits the ipsilateral abducens nucleus; hence, damage to the MVN causes decreased activity of the contralesional abducens nucleus and increased activity of the ipsilesional abducens nucleus, resulting in ipsilesional HGD (Figure 3C).…”

“…[3][4][5] Small lesions can also evoke PHGD as observed in ischemia of the frontal eye field, 7 pons, 8 and lateral medulla. 9 Infarcts of the cerebral hemisphere often cause ipsilesional PHGD, whereas pontine and cerebellar infarcts can evoke contralesional PHGD. 8 In patients with lateral medullary infarction, ipsilesional PHGD is occasionally found.…”

Radiographic horizontal gaze deviation in the setting of acute PICA territory ischemia: A potential mimic of large vessel occlusion

“…In anterior circulation stroke, even a small area of ischemia may result in gaze deviation, if it affects the cortical regions controlling voluntary eye movement, including the frontal eye fields (FEF, Brodmann area), basal ganglia, parietal eye fields, and neighboring temporoparietal cortical regions [7][8][9]. Gaze deviation in PICA territory strokes may be attributed to ischemia in the flocculonodular lobe, vermis, and lateral medulla [10][11][12][13][14][15][16]20].…”

“…Two patients with both vermis and flocculonodular lobe ischemia also demonstrated ipsilateral HGD. Furthermore, the presence of ipsilateral HGD may also be explained by ischemia in the lateral medulla (lateral medullary syndrome), which is usually caused by occlusion of the ipsilateral vertebral artery and/or PICA [15][16][17]. The mechanism proposed includes disruption of the connections from the paravermian region of the cerebellum to the PPRF, where the last supranuclear stage of the lateral gaze pathway occurs [15].…”

“…Furthermore, the presence of ipsilateral HGD may also be explained by ischemia in the lateral medulla (lateral medullary syndrome), which is usually caused by occlusion of the ipsilateral vertebral artery and/or PICA [15][16][17]. The mechanism proposed includes disruption of the connections from the paravermian region of the cerebellum to the PPRF, where the last supranuclear stage of the lateral gaze pathway occurs [15]. In our study, 5 of the 20 patients with radiological (+) HGD had lateral medullary infarcts: 2 patients displayed ipsilateral HGD, and 3 displayed contralateral HGD, suggesting different ocular outcomes depending on the intricacy of input from multiple neurological networks in balancing vestibular tone.…”