Consensus paper: management of degenerative cerebellar disorders

Abstract

Treatment of motor symptoms of degenerative cerebellar ataxia remains difficult. Yet there are recent developments that are likely to lead to significant improvements in the future. Most desirable would be a causative treatment of the underlying cerebellar disease. This is currently available only for a very small subset of cerebellar ataxias with known metabolic dysfunction. However, increasing knowledge of the pathophysiology of hereditary ataxia should lead to an increasing number of medically sensible drug trials. In this paper, data from recent drug trials in patients with recessive and dominant cerebellar ataxias will be summarized. There is consensus that up to date, no medication has been proven effective. Aminopyridines and acetazolamide are the only exception, which are beneficial in patients with episodic ataxia type 2. Aminopyridines are also effective in a subset of patients presenting with downbeat nystagmus. As such, all authors agreed that the mainstays of treatment of degenerative cerebellar ataxia are currently physiotherapy, occupational therapy, and speech therapy. For many years, well-controlled rehabilitation studies in patients with cerebellar ataxia were lacking. Data of recently published studies show that coordinative training improves motor function in both adult and juvenile patients with cerebellar degeneration. Given the well-known contribution of the cerebellum to motor learning, possible mechanisms underlying improvement will be outlined. There is consensus that evidence-based guidelines for the physiotherapy of degenerative cerebellar ataxia need to be developed. Future developments in physiotherapeutical interventions will be discussed including application of non-invasive brain stimulation.

Fig. 1

Effect of re-boost rehabilitation on cerebellar ataxia as assessed by SARA scores in patients with cerebellar degenerative diseases. All four patients underwent 4-week intensive rehabilitation (CAR trial; Miyai, unpublished). Cases 2 and 3 had re-boost intensive rehabilitation twice, and cases 1 and 4 had re-boost rehabilitation once. First intervention results in 2.5 point improvement of SARA on average, and after average of 26 weeks, SARA worsened by 7.6 points and the re-boost therapy resulted in 2.0 point improvement. This suggests that the effect of re-boost rehabilitation on SARA was comparable with the first intensive rehabilitation. However, low-intensity home therapy up to 80 min per week failed to maintain the gains. Solid lines represent intervention periods of intensive rehabilitation. Dotted lines represent follow-up periods with home-based rehabilitation of 40 to 80 min per week

Fig. 2

a Screenshots from the game “Light Race” used in the exercises. b Snapshot from the “Light Race” game. Patient C1 performs dynamic stepping movements in order to control the avatar to step onto the highlighted areas on the floor (figures reproduced with permission from Microsoft Xbox Kinect^® (a, b)). c, d Group comparisons of the clinical ataxia scores (SARA) and lateral sway in gait at examinations E1–E4. Patients were examined four times: 2 weeks before intervention (E1), immediately before the first training session (E2), after the 2-week lab-training period (E3), and after the 6-week home-training phase (E4)[106]. Stars denote significance: *p <0.05; **p <0.01