The outcome of the movement disorder in methcathinone abusers: clinical, MRI and manganesemia changes, and neuropathology.

BACKGROUND AND PURPOSE: There is limited knowledge regarding the long-term outcome of the methcathinone/manganese-induced movement disorder. Our purpose was to define prognosis in intravenous methcathinone abusers affected by this distinctive disorder attributed to manganese (Mn) toxicity. Also, neuropathology from a globus pallidus region biopsy from a former user is reported. METHODS: Eighteen methcathinone abusers were categorized as active (five), discontinued (four) or former (nine) users. They were reassessed after a median of 32.5 months (range 3.4-59.6) clinically, on rating scales, and with MRI and blood Mn levels. The biopsy was examined ultrastructurally. RESULTS: Overall the group showed a slight tendency to deterioration at follow-up on clinical assessment of motor functioning, especially the active users. No significant change occurred on parkinsonian rating scale reassessment. Significant reduction in Mn levels occurred in former users, and decreased T1-weighted hyperintensity on basal ganglia MRI occurred in 3 of 4 former and 2 of 3 discontinued users, despite lack of clinical improvement. The biopsy consisted of white matter showing decompacted myelin sheaths and frequent abnormalities of mitochondria. CONCLUSIONS: No improvement in this Mn-induced movement disorder occurs after cessation of methcathinone abuse despite improvement of Mn blood levels and/or MRI abnormalities. Ultrastructural abnormalities in a former user confirm structural damage to white matter is associated with the disorder. Methcathinone/Mn toxicity is an important, disabling and permanent medical sequel of intravenous drug abuse in the former Soviet Union.

Biomechanical and structural assessment of transluminal angioplasty.

The increasing incidence of stroke is frequently maintained by the processes narrowing precerebral and cerebral arteries. That is why the surgical treatment of cerebrovascular disorders has increasingly included percutaneous transluminal angioplasty. However, the influence of transluminal angioplasty on the biomechanical properties of arterial wall have not been assessed so far. The cylindrical segments of left and right internal carotid artery, middle cerebral artery, anterior cerebral artery, vertebral artery, basilar artery and posterior cerebral artery were taken from 40 autopsy subjects aged from 20 to 75 who had no systemic lesions with the exception of atherosclerosis. The biomechanical examination and experimental transluminal angioplasty of the segments were carried out with special equipment developed for this purpose. The data were obtained using a TV camera assisted measurement and morphometric and histological methods. The examination of the biomechanical properties repeated after the experimental transluminal angioplasty shows the additional relative strain of the external diameter of vessel and the decrease of the arterial wall tangential elastic modulus in the circumferential direction. This suggests that if transluminal angioplasty results in sufficient structural damage of the arterial wall than there will be an improvement in the ability of the vessel diameter to increase under normal blood pressure conditions.