Electrocochleography Results in Patients With Bilateral Vestibular Paresis and Sound- or Pressure-Induced Horizontal Nystagmus

Marijuana consists of a mixture of dried leaves and flowers of the plant Cannabis sativa. Animals are usually poisoned by accidental ingestion. The effects of the plant are associated with cannabinoids, which are not found in other plant species. An increase in poisoning cases in dogs was observed in some states of the USA. In Brazil, reports are scarce. The objective of this study is to report a case of a dog intoxicated by marijuana. The animal was admitted to the hospital with incoordination, depression, mydriasis, decreased pupillary reflex, horizontal nystagmus, opisthotonos, bradycardia, and obnubilation. The patient was hospitalized and subjected to supportive treatment, since there is no antidote for this kind of poisoning. Patient recovery took approximately 36 hours.

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022 Patient-initiated event monitoring for acute vertigo

Journal of Neurology Neurosurgery & Psychiatry ◽

10.1136/jnnp-2019-anzan.21 ◽

2019 ◽

Vol 90 (e7) ◽

pp. A8.2-A8

Author(s):

Allison S Young ◽

Corinna Lechner ◽

Andrew P Bradshaw ◽

Hamish G MacDougall ◽

Deborah A Black ◽

...

Keyword(s):

Spontaneous Nystagmus ◽

Slow Phase ◽

Vestibular Disorders ◽

Positional Nystagmus ◽

Low Velocity ◽

Event Monitoring ◽

Superior Semicircular Canal Dehiscence ◽

Positional Vertigo ◽

Horizontal Nystagmus ◽

Vertical Nystagmus

IntroductionThe diagnosis of vestibular disorders may be facilitated by analysing patient-initiated capture of ictal nystagmus.MethodsAdults with a history of recurrent vertigo were taught to self-record spontaneous and positional-nystagmus at home while symptomatic, using video-goggles. Patients with final diagnoses of disorders presenting with recurrent vertigo were analysed: 121 patients with Ménière’s Disease (MD), Vestibular Migraine (VM), Benign Positional Vertigo (BPV), Episodic Ataxia Type II (EAII), Vestibular Paroxysmia (VP) or Superior Semicircular Canal Dehiscence (SSCD) were included.ResultsOf 43 MD patients, 40 showed high-velocity spontaneous horizontal-nystagmus (median slow-phase velocity (SPV) 39.7 degrees/second (°/s); Twenty-one showed horizontal-nystagmus reversing direction within 12-hours (24 on separate days). In 44 of 67 patients with VM, low velocity spontaneous horizontal (n=28, 4.9°/s), up-beating (n=6, 15.5°/s) or down-beating-nystagmus (n=10, 5.1°/s) was observed; Sixteen showed positional-nystagmus only, and seven had no nystagmus. Spontaneous horizontal-nystagmus with SPV >12.05°/s had a sensitivity and specificity of 95.3% and 82.1% for MD. Nystagmus direction-change within 12-hours was highly specific (95.7%) for MD. Spontaneous vertical-nystagmus was highly specific (93.0%) for VM. In the seven BPV patients, spontaneous-nystagmus was absent or <3°/s, and characteristic paroxysmal positional nystagmus was observed in all cases. Patients with central and MD-related positional vertigo demonstrated persistent nystagmus. Two patients with EAII showed spontaneous vertical nystagmus, one patient with VP showed short bursts of horizontal-torsional nystagmus lasting 5–10s, and one patient with SSCD demonstrated paroxysmal torsional down-beating nystagmus when supine.ConclusionsPatient-initiated vestibular event-monitoring is feasible and could facilitate rapid and accurate diagnosis of episodic vestibular disorders.

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Nystagmus characteristics of healthy controls

Journal of Vestibular Research ◽

10.3233/ves-200022 ◽

2020 ◽

Vol 30 (6) ◽

pp. 345-352

Author(s):

Allison S. Young ◽

Sally M. Rosengren ◽

Mario D’Souza ◽

Andrew P. Bradshaw ◽

Miriam S. Welgampola

Keyword(s):

Upright Position ◽

Community Dwelling ◽

Spontaneous Nystagmus ◽

Slow Phase ◽

Healthy Controls ◽

Positional Nystagmus ◽

Low Velocity ◽

Video Oculography ◽

Significant Difference ◽

Horizontal Nystagmus

BACKGROUND: Healthy controls exhibit spontaneous and positional nystagmus which needs to be distinguished from pathological nystagmus. OBJECTIVE: Define nystagmus characteristics of healthy controls using portable video-oculography. METHODS: One-hundred and one asymptomatic community-dwelling adults were prospectively recruited. Participants answered questions regarding their audio-vestibular and headache history and were sub-categorized into migraine/non-migraine groups. Portable video-oculography was conducted in the upright, supine, left- and right-lateral positions, using miniature take-home video glasses. RESULTS: Upright position spontaneous nystagmus was found in 30.7% of subjects (slow-phase velocity (SPV)), mean 1.1±2.2 degrees per second (°/s) (range 0.0 – 9.3). Upright position spontaneous nystagmus was horizontal, up-beating or down-beating in 16.7, 7.9 and 5.9% of subjects. Nystagmus in at least one lying position was found in 70.3% of subjects with 56.4% showing nystagmus while supine, and 63.4% in at least one lateral position. While supine, 20.8% of subjects showed up-beating nystagmus, 8.9% showed down-beating, and 26.7% had horizontal nystagmus. In the lateral positions combined, 37.1% displayed horizontal nystagmus on at least one side, while 6.4% showed up-beating, 6.4% showed down-beating. Mean nystagmus SPVs in the supine, right and left lateral positions were 2.2±2.8, 2.7±3.4, and 2.1±3.2°/s. No significant difference was found between migraine and non-migraine groups for nystagmus SPVs, prevalence, vertical vs horizontal fast-phase, or low- vs high-velocity nystagmus (<5 vs > 5°/s). CONCLUSIONS: Healthy controls without a history of spontaneous vertigo show low velocity spontaneous and positional nystagmus, highlighting the importance of interictal nystagmus measures when assessing the acutely symptomatic patient.

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