These results indicate that for ROT and vHIT tests, central compensation is observed in CPR and no-CPR patients. It acts primarily by increasing deficit side responses. Central compensation provides approximately 60% of the VOR improvement for CPR patients. The rest of the improvement is due to peripheral recovery which appears necessary to reduce VOR asymmetry to normal at 13 weeks on average. Balance control improvement is more rapid than that of the VOR and marginally affected by the lack of peripheral recovery. Both VOR and balance control measures at onset provide indicators of future peripheral recovery. For these reasons VOR and balance control needs to be tested at aUPVD onset and at 13 weeks.

BackgroundAn acute unilateral peripheral vestibular loss (aUVL) initially causes severe gaze and balance control problems. However, vestibulo-ocular reflexes (VOR) and balance control are nearly normal 3 months later as a result of peripheral recovery and/or central compensation. As pre-existing vestibular sensory loss is assumed to be greater in the healthy elderly, this study investigated whether improvements in VOR and balance function over time after aUVL are different for the elderly than for the young.MethodsThirty aUVL patients divided into three age-groups were studied (8 age range 23–35, 10 with range 43–58, and 12 with range 60–74 years). To measure VOR function eye movements were recorded during caloric irrigation, rotating chair (ROT), and head impulse tests. Balance control during stance and gait was recorded as lower trunk angular velocity in the pitch and roll planes. Measurements were taken at deficit onset, and 3, 6, and 13 weeks later.ResultsThere was one difference in VOR improvements over time between the age-groups: Low acceleration ROT responses were less at onset in the elderly group. Deficit side VOR responses and asymmetries in each group improved to within ranges of healthy controls at 13 weeks. Trunk sway of the elderly was greater for stance and gait at onset when compared to healthy age-matched controls and the young and greater than that of the young and controls during gait tasks at 13 weeks. The sway of the young was not different from controls at either time point. Balance control for the elderly improved slower than for the young.ConclusionThese results indicate that VOR improvement after an aUVL does not differ with age, except for low accelerations. Recovery rates are different between age-groups for balance control tests. Balance control in the elderly is more abnormal at aUVL onset for stance and gait tasks with the gait abnormalities remaining after 13 weeks. Thus, we conclude that balance control in the elderly is more affected by the UVL than for the young, and the young overcome balance deficits more rapidly. These differences with age should be taken into account when planning rehabilitation.

Aims: To compare balance changes over time during the relapse phase of relapsing-remitting multiple sclerosis (RRMS) with balance control during the remitting phase.Methods: Balance control during stance and gait tasks of 24 remitting-phase patients (mean age 43.7 ± 10.5, 15 women, mean EDSS at baseline 2.45 ± 1.01) was examined every 3 months over 9 months and compared to that of nine relapsing patients (age 42.0 ± 12.7, all women, mean EDSS at relapse onset 3.11 ± 0.96) examined at relapse onset and 3 months later. Balance was also compared to that of 40 healthy controls (HCs) (age 39.7 ± 12.6, 25 women). Balance control was measured as lower-trunk sway angles with body-worn gyroscopes. Expanded Disability Status Scale scores (EDSS) were used to monitor, clinically, disease progression.Results: Remitting-phase patients showed more unstable stance balance control than HCs (p < 0.04) with no worsening over the observation period of 9 months. Gait balance control was normal (p > 0.06). Relapsing patients had stance balance control significantly worse at onset compared to remitting-phase patients and HCs (p < 0.04). Gait tasks showed a significant decrease of gait speed and trunk sway in relapsing patients (p = 0.018) compatible with having increased gait instability at normal speeds. Improvement to levels of remitting patients generally took longer than 3 months. Balance and EDSS scores were correlated for remitting but not for relapse patients.Conclusions: Balance in remitting RRMS patients does not change significantly over 9 months and correlated well with EDSS scores. Our results indicate that balance control is a useful measure to assess recovery after a relapse, particularly in patients with unchanged EDSS scores. Based on our results, balance could be considered as additional measurement to assess recovery after a relapse, particularly in patients with unchanged EDSS.