Is the dynamic gait index a useful outcome to measure balance and ambulation in patients with cerebellar ataxia?

The Scale for Assessment and Rating of Ataxia Is Reliable and Valid in the Telehealth Setting for Patients With Cerebellar Ataxia

OBJECTIVE

Health care has increasingly expanded into a hybrid in-person/telehealth model. Patients with a variety of health conditions, including cerebellar ataxia, have received virtual health evaluations; however, it remains unknown whether some outcome measures that clinicians utilize in the telehealth setting are reliable and valid. The goal of this project is to evaluate the psychometric properties of the Scale for Assessment and Rating of Ataxia (SARA) for patients with cerebellar ataxia in the telehealth setting.

METHODS

Nineteen individuals with cerebellar impairments were recruited on a voluntary basis. Participants completed 2 30-minute testing sessions during which a clinical examination and the SARA were performed. One session was performed in person, and the other session was assessed remotely. Outcome measure performance was video recorded in both environments and independently scored by 4 additional raters with varying levels of clinical experience (ranging from 6 months to 29 years). Concurrent validity was assessed with the Spearman rank order correlation coefficient (α < .05), comparing the virtual SARA scores to their gold standard in-person scores. Interrater reliability was evaluated with the intraclass correlation coefficient (ICC) (2,4) (α < .05).

RESULTS

Fourteen of the 19 participants completed both in-person and telehealth SARA evaluations. We found that the in-person SARA and the telehealth SARA have large concurrent validity (Spearman rho significant at the 2-tailed α of .01 = 0.90; n = 14). Additionally, raters of varying years of experience had excellent interrater reliability for both the in-person SARA (ICC [2,4] = 0.97; n = 19) and the telehealth SARA (ICC [2,4] = 0.98; n = 14).

CONCLUSION

Our results show that the telehealth SARA is comparable to the in-person SARA. Additionally, raters of varying years of clinical experience were found to have excellent interrater reliability scores for both remote and in-person SARA evaluations.

IMPACT

Our study shows that the SARA can be used in the telehealth setting for patients with ataxia.

Effectiveness of vestibular rehabilitation therapy in patients with idiopathic Cerebellar Ataxia with Bilateral Vestibulopathy (iCABV)

OBJECTIVE

To evaluate the benefit of vestibular rehabilitation therapy (VRT) in the management of patients with idiopathic cerebellar ataxia with bilateral vestibulopathy (iCABV).

BACKGROUND

iCABV is a hindbrain degenerative disorder with impairment of both central and peripheral vestibular pathways. There is combined failure of four compensatory eye movement systems including the vestibulo-ocular reflex (VOR), optokinetic reflex, smooth pursuit and the visually enhanced vestibulo-ocular reflex (VVOR). Phenotypic presentation includes postural and gait instability, oscillopsia and dizziness with active head movement. The benefit of VRT in iCABV patients has not been established.

METHODS

A retrospective review was performed on a cohort of twelve patients diagnosed with iCABV in a multidisciplinary neuro-otology clinic. All participated in VRT and completed their suggested course of VRT. The following clinical measures were assessed before starting and after finishing VRT: 1) Dizziness Handicap Inventory (DHI), 2) Activities-Specific Balance Confidence (ABC) Scale, 3) Catastrophization scale, 4) Positive Affective Negative Affective Score (PANAS), 5) Dynamic Gait Index (DGI) and 6) Modified Clinical Test of Sensory Interaction in Balance (mCTSIB). The number of falls historically was recorded in addition to gait speed (ft./sec).

RESULTS

Following VRT, patients were found to have improved balance on mCTSIB (condition 4 : 7 vs 18 seconds, P = 0.04) and a better postural stability with a reduced number of falls (p = 0.01). No statistically significant improvement was seen in the DHI, ABC, Catastrophization scale, DGI, PANAS and gait speed (p > 0.05).

CONCLUSIONS

iCABV patients who underwent VRT were found to have a better postural stability and reduced risk of falls. VRT was not found to significantly improve patients' overall subjective perception of their symptoms or their psychological status.

Report of oscillopsia in ataxia patients correlates with activity, not vestibular ocular reflex gain

BACKGROUND

Patients with cerebellar ataxia report oscillopsia, "bouncy vision" during activity, yet little is known how this impacts daily function. The purpose of this study was to quantify the magnitude of oscillopsia and investigate its relation to vestibulo-ocular reflex (VOR) function and daily activity in cerebellar ataxia.

METHODS

19 patients diagnosed with cerebellar ataxia and reports of oscillopsia with activity were examined using the video head impulse test (vHIT), Oscillopsia Functional Index (OFI), and clinical gait measures. Video head impulse data was compared against 40 healthy controls.

RESULTS

OFI scores in ataxia patients were severe and inversely correlated with gait velocity (r = -0.55, p <  0.05), but did not correlate with VOR gains. The mean VOR gain in the ataxic patients was significantly reduced and more varied compared with healthy controls. All patients had abnormal VOR gains and eye/head movement patterns in at least one semicircular canal during VHIT with passive head rotation.

CONCLUSIONS

Patients with cerebellar ataxia and oscillopsia have impaired VOR gains, yet severity of oscillopsia and VOR gains are not correlated. Patients with cerebellar ataxia have abnormal oculomotor behavior during passive head rotation that is correlated with gait velocity, but not magnitude of oscillopsia.