Progressive supranuclear palsy. Neurodegenerative Diseases. Cambridge University Press; 2010. pp. 663-81. [DOI: 10.1017/cbo9780511544873.045]

Improvement of balance after audio-biofeedback. A 6-week intervention study in patients with progressive supranuclear palsy

Progressive supranuclear palsy (PSP) is a neurodegenerative disease with no sufficient treatment options to date. The most devastating symptom is the loss of balance with consecutive falls. Based on the observation that postural control improved in patients with vestibular dysfunction after audio-biofeedback training, we tested the effects of this training in PSP patients. Eight PSP patients were included into an uncontrolled 6-week intervention trial. The focus of the training was the improvement of posture and dynamic balance by using audio-biofeedback. The device was well accepted. No adverse events occurred. A significant improvement in the Berg Balance Scale was observed (T2 vs. T1, p=0.016), which remained significant at the 4-week follow-up (T3 vs. T1, p=0.008). Significant improvement of the Parkinson's disease questionnaire was demonstrated. No significant changes were found in the Timed Up-and-Go Test, the Five Chair Rise Test, and in specific clinical scales. To our knowledge, the present study is the first to demonstrate that audio-biofeedback training with PSP patients is associated with improvements of balance and psychosocial aspects.

Clinical and dual-tasking aspects in frequent and infrequent fallers with progressive supranuclear palsy

Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease with no sufficient therapeutic options to date. Falls are the most devastating feature. The causes of these falls are not well understood. To test the impact of PSP-associated motor and cognitive features on falls, 26 PSP patients were prospectively recruited and divided into frequent fallers (> one fall/month, 18 patients) and infrequent fallers (<or= one fall/month, 8 patients). Further parameters were assessed by clinical investigation and biomechanical gait and balance analysis with and without dual-task paradigms. Physical activity was measured through an ambulatory device. Frequent fallers scored higher on the total PSP rating scale and the subscales "history," "mental," "bulbar," "supranuclear ocular motor," and "gait/midline exam" but not on disease duration, the subscale "limb exam," the UPDRS motor score and the sway analysis. Frequent fallers also showed an increased probability of an altered walking pattern with shortened step lengths and increased cadence under a dual-task situation. It is concluded that the occurrence of falls in PSP seems strongly associated with the deterioration of bulbar function, but not relevantly with typical parkinsonian features like rigidity and bradykinesia. The decreased ability to deal with distraction of attention under a dual-task situation points to a relevant impact of cortical and subcortical dysfunction on the frequency of falls.

Substantia nigra echogenicity in progressive supranuclear palsy

A normoechogenic substantia nigra (SN) is a typical finding in transcranial sonography in patients with progressive supranuclear palsy (PSP), whereas in patients with Parkinson's disease a hyperechogenic SN is characteristic. A recent classification scheme recommends the differentiation of PSP patients into those with Richardson's syndrome (RS) and those with PSP-Parkinsonism (PSP-P). We investigated 34 PSP patients (27 RS, 7 PSP-P) with ultrasound of the substantia nigra in search of differentiations in the two groups. We found that most of the PSP-P patients, according to recently published criteria, had a hyperechogenic SN (6 of 7): right (cm(2)) median 0.22, 25% percentile 0.21 and 75% percentile 0.36 (cm(2)); left (cm(2)) median 0.21, 25% percentile 0.20 and 75% percentile 0.30 and a normal third ventricle (mean mm) +/-SD: 7.1 +/- 2.43). In RS patients a normoechogenic SN (26 of 27) and an enlarged third ventricle (mean mm) +/-SD: 10.3 +/- 2.41) was found. These differences may elucidate the pathological differences of RS and PSP-P.

Iron metabolism in Parkinsonian syndromes

Growing evidence suggests an involvement of iron in the pathophysiology of neurodegenerative diseases. Several of the diseases are associated with parkinsonian syndromes, induced by degeneration of basal ganglia regions that contain the highest amount of iron within the brain. The group of neurodegenerative disorders associated with parkinsonian syndromes with increased brain iron content can be devided into two groups: (1) parkinsonian syndromes associated with brain iron accumulation, including Parkinson's disease, diffuse Lewy body disease, parkinsonian type of multiple system atrophy, progressive supranuclear palsy, corticobasal ganglionic degeneration, and Westphal variant of Huntington's disease; and (2) monogenetically caused disturbances of brain iron metabolism associated with parkinsonian syndromes, including aceruloplasminemia, hereditary ferritinopathies affecting the basal ganglia, and panthotenate kinase associated neurodegeneration type 2. Although it is still a matter of debate whether iron accumulation is a primary cause or secondary event in the first group, there is no doubt that iron-induced oxidative stress contributes to neurodegeneration. Parallels concerning pathophysiological as well as clinical aspects can be drawn between disorders of both groups. Results from animal models and reduction of iron overload combined with at least partial relief of symptoms by application of iron chelators in patients of the second group give hope that targeting the iron overload might be one possibility to slow down the neurodegenerative cascade also in the first group of inevitably progressive neurodegenerative disorders.