Cervico-ocular reflex upregulation in dizzy patients with asymmetric neck pathology (original) (raw)
Related papers
The Bárány Society position on ‘Cervical Dizziness’
Journal of vestibular research, 2022
This paper describes the Bárány Society Classification OverSight Committee (COSC) position on Cervical Dizziness, sometimes referred to as Cervical Vertigo. This involved an initial review by a group of experts across a broad range of fields, and then subsequent review by the Bárány Society COSC. Based upon the so far published literature, the Bárány Society COSC takes the view that the evidence supporting a mechanistic link between an illusory sensation of self-motion (i.e. vertigo-spinning or otherwise) and neck pathology and/or symptoms of neck pain-either by affecting the cervical vertebrae, soft tissue structures or cervical nerve roots-is lacking. When a combined head and neck movement triggers an illusory sensation of spinning, there is either an underlying common vestibular condition such as migraine or BPPV or less commonly a central vestibular condition including, when acute in onset, dangerous conditions (e.g. a dissection of the vertebral artery with posterior circulation stroke and, exceedingly rarely, a vertebral artery compression syndrome). The Committee notes, that migraine, including vestibular migraine, is by far, the commonest cause for the combination of neck pain and vestibular symptoms. The committee also notes that since head movement aggravates symptoms in almost any vestibular condition, the common finding of increased neck muscle tension in vestibular patients, may be linked as both cause and effect, to reduced head movements. Additionally, there are theoretical mechanisms, which have not been explored, whereby cervical pain may promote vaso-vagal, cardio-inhibitory reflexes and hence by presyncopal mechanisms, elicit transient disorientation and/or imbalance. The committee accepts that further research is required to answer the question as to whether those rare cases in which neck muscle spasm is associated with a vague sense of spatial disorientation and/or imbalance, is indeed linked
Acta Oto-laryngologica, 2006
Conclusions. When considering benign recurrent vertigo and a similar peripheral vestibular deficiency, the asymmetry of the vestibulo-ocular reflex (VOR) time constant (Tc) is lower in those patients with paretic head-shaking nystagmus (HSN) than in those with reversed HSN or without HSN. Objective. To determine whether the existence of HSN is related to the time constant of the VOR in patients with benign recurrent vertigo (BRV). Patients and methods. This was a prospective study conducted at a tertiary care center in which patients were subjected to the head-shaking test, the caloric test and rotatory chair impulsive test on the same day. The clinical features of the disease analyzed were the disease duration, frequency of vertigo spells, time since the last vertigo spell and the existence of migraine. The results of the head-shaking test were considered positive when nystagmus appeared after head-shaking had ended. Two groups of patients were established on the basis of these results and the group that displayed HSN was divided according to the direction of nystagmus. In the impulsive test, the time constant of the VOR after ipsilesional and contralesional acceleration was analyzed, as was the symmetry of the response. The differences in the means were calculated. Results. BRV was diagnosed in 25% of patients suffering recurrent spells of vertigo, of which 33 patients were HSN(/ and 29 were HSN'/. In the latter group, vestibular migraine was frequently observed (83% of the patients), the spells of vertigo were more frequent and the patients were seen closer to the previous spell of vertigo. No differences were observed in the Tc of the VOR between HSN'/ and HSN(/ patients, although the asymmetry of this Tc was higher in HSN(/ patients than in HSN'/ patients. Nevertheless, the differences observed were only significant between paretic and reversed HSN patients and paretic HSN patients and HSN(/ patients.
Active head rotation in benign positional paroxysmal vertigo
Brazilian Journal of Otorhinolaryngology (impresso), 2009
Beni gn Positional Paroxysmal Vertigo (BPPV) is one of the most common vestibular diseases and the active head rotation test one of the most modern methods of vestibular function assessment. Aim: this study aims to verify if the active head rotation test may reveal signs of horizontal and/or vertical vestibulo-ocular reflex dysfunction in vertigo patients suspected for BPPV. Study design: retrospective series study. Materials and Method: Neurotological evaluation including computerized electronystagmography and active head rotation on the horizontal and vertical axes were conducted in 100 patients suspected for BPPV patients. Results: Isolated or associated abnormalities of the horizontal and/or vertical vestibulo-ocular reflex gain, phase and symmetry were indicative of vestibular involvement and found in 77.0% of the BPPV patients. Conclusion: the active head rotation test revealed horizontal and/or vertical vestibulo-ocular reflex dysfunctions in a relevant number of BPPV patients.
Frontiers in Neurology
Background: The primate ocular motor system is designed to acquire peripheral targets of interest by coordinating visual, vestibular, and neck muscle activation signals. The vestibulo-ocular reflex (VOR) is greatly reduced at the onset of large eye-head (gaze) saccades and resumes before the end of the saccades to stabilize eye-in-orbit and ensure accurate target acquisition. Previous studies have relied on manipulating head movements in normal individuals to study VOR suppression and gaze kinematics. We sought to determine if reduced head-on-trunk movement alters VOR suppression and gaze accuracy similar to experiments involving normal subjects and if intentionally increasing head and neck movement affects these dynamics.
Cervical kinematics in patients with vestibular pathology vs. patients with neck pain: A pilot study
Journal of Vestibular Research, 2017
OBJECTIVE: Research has consistently shown cervical kinematic impairments in subjects with persistent neck pain (NP). It could be reasoned that those with vestibular pathology (VP) may also have altered kinematics since vestibular stimulation via head movement can cause dizziness and visual disturbances. However, this has not been examined to date. This pilot study investigated changes in cervical kinematics between asymptomatic control, NP and VP subjects using a Virtual Reality (VR) system. It was hypothesised that there would be altered kinematics in VP subjects, which might be associated with dizziness and visual symptoms. DESIGN: Pilot cross sectional observational study. PARTICIPANTS: Twenty control, 14 VP and 20 NP subjects. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Measures included questionnaires (neck disability index, pain on movement, dizziness and pain intensity, visual disturbances) and cervical kinematics (range, peak and mean velocity, smoothness, symmetry, and accuracy of cervical motion) using a virtual reality system. RESULTS: Results revealed significantly decreased mean velocity and symmetry of motion in both planes in those with NP but no differences in accuracy or range of motion. No significant differences were seen between VP subjects and asymptomatic controls. However, correlation analysis showed some moderate correlations between dizziness to selected kinematics in both the NP and the VP groups. CONCLUSIONS: These results support that cervical kinematics are altered in NP patients, with velocity most affected. There is potential for VP subjects to also have altered kinematics, especially those who experience dizziness. More research is required.