The role of the nucleus intercalatus in vertical gaze holding

Aim. To evaluate the profile of ocular gaze abnormalities occurring following stroke. Methods. Prospective multicentre cohort trial. Standardised referral and investigation protocol including assessment of visual acuity, ocular alignment and motility, visual field, and visual perception. Results. 915 patients recruited: mean age 69.18 years (SD 14.19). 498 patients (54%) were diagnosed with ocular motility abnormalities. 207 patients had gaze abnormalities including impaired gaze holding (46), complete gaze palsy (23), horizontal gaze palsy (16), vertical gaze palsy (17), Parinaud’s syndrome (8), INO (20), one and half syndrome (3), saccadic palsy (28), and smooth pursuit palsy (46). These were isolated impairments in 50% of cases and in association with other ocular abnormalities in 50% including impaired convergence, nystagmus, and lid or pupil abnormalities. Areas of brain stroke were frequently the cerebellum, brainstem, and diencephalic areas. Strokes causing gaze dysfunction also involved cortical areas including occipital, parietal, and temporal lobes. Symptoms of diplopia and blurred vision were present in 35%. 37 patients were discharged, 29 referred, and 141 offered review appointments. 107 reviewed patients showed full recovery (4%), partial improvement (66%), and static gaze dysfunction (30%). Conclusions. Gaze dysfunction is common following stroke. Approximately one-third of patients complain of visual symptoms, two thirds show some improvement in ocular motility.

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Artery of Percheron infarction with persistent amnesia: a case report of bilateral paramedian thalamic syndrome

BMC Neurology ◽

10.1186/s12883-020-01949-0 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Hannah E. Snyder ◽

Sheliza Ali ◽

Joanna Sue ◽

Ayse Unsal ◽

Crystal Fong ◽

...

Keyword(s):

Time Window ◽

Neuropsychological Testing ◽

First Year ◽

Artery Of Percheron ◽

Wide Range ◽

Level Of Consciousness ◽

Midbrain Infarction ◽

Vertical Gaze

Abstract Background The artery of Percheron is an uncommon anatomic variant which supplies the bilateral paramedian thalami and rostral midbrain. While infarction of its vascular territory can result in a wide range of symptoms, paramedian thalamic syndrome is classically described as a triad of symptoms including vertical gaze disturbances, fluctuating level of consciousness, and amnesia. There is minimal evidence to date to characterize the long-term cognitive consequences of infarction of the artery of Percheron utilizing neuropsychological assessment. Case presentation We describe a 40-year-old female patient initially presenting with dizziness, confusion and falls with unremarkable head CT scans. Subsequent MRI, more than 24 h after symptom onset, identified evidence of bilateral thalamic and rostral midbrain infarction. Neuropsychological testing was administered at 4 months post-stroke, with follow up testing at 1 year. The patient was found to have profound anterograde and retrograde amnesia, which did not change significantly over the first year of rehabilitation, and which was not easily identifiable in everyday encounters due to her relatively intact working memory and social skills. Conclusions As early diagnosis of infarction of the artery of Percheron is challenging, patients have frequently missed the time window for acute management of ischemic stroke. Moreover, this case study highlights the need for further research in deciphering the role of the paramedian thalamus in memory and cognition, as well as the importance of standardized neuropsychological testing for the artery of Percheron stroke patients to identify safety and rehabilitation concerns that may be overlooked.

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Role of Premotor Vestibular Nucleus Neurons in Vertical Gaze

Acta Oto-Laryngologica ◽

10.3109/00016489109131377 ◽

1991 ◽

Vol 111 (sup481) ◽

pp. 187-190

Author(s):

Yoshiki Iwamoto ◽

Toshihiro Kitama ◽

Kaoru Yoshida

Keyword(s):

Vestibular Nucleus ◽

Vertical Gaze

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The role of the vestibular commissure in the gaze holding of the cat

Neuroscience Letters ◽

10.1016/0304-3940(93)90309-9 ◽

1993 ◽

Vol 153 (2) ◽

pp. 149-152 ◽

Cited By ~ 5

Author(s):

E. Godaux ◽

G. Cheron

Keyword(s):

The Gaze ◽

Gaze Holding

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Gaze Control

10.1093/med/9780190237493.003.0019 ◽

2017 ◽

Author(s):

Peggy Mason

Keyword(s):

Eye Movements ◽

Smooth Pursuit ◽

Neural Circuits ◽

Psychiatric Diseases ◽

Gaze Control ◽

Optokinetic Response ◽

Social Signal ◽

Horizontal Gaze ◽

Vertical Gaze

In addition to serving perception, gaze acts as a powerful social signal and mode of communication. Gaze is altered in several psychiatric diseases and impaired by a variety of central and peripheral lesions. Eye movements that serve to stabilize gaze include the vestibuloocular reflex (VOR) and fixation, whereas eye movements that shift gaze include saccades, cancellation of the VOR, and smooth pursuit. The pontine horizontal gaze center and midbrain vertical gaze center connect to extraocular motoneurons and mediate all eye movements. Neural circuits involved in generating the VOR, horizontal saccades and saccade modulation are described in detail. Nystagmus consequent to unilateral labyrinthine damage is explained. Other forms of nystagmus including the optokinetic response are introduced. The role of internuclear interneurons in coordinating horizontal saccades and their failure in internuclear ophthalmalplegia are detailed. Finally, the mechanisms involved in fixation and smooth pursuit are briefly presented.

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