[Usefulness of SPECT and MRI in the diagnosis of atypical parkinsonism].

Background: Clinico-pathological studies have shown that only three out of four patients with parkinsonism have idiopathic Parkinson's disease. In patients with so-called Parkinson plus syndrome, the degeneration in the brain is more widespread and the variety of neurological signs greater than in Parkinson's disease. The differentiation of these syndromes from Parkinson's disease can be difficult.

Linkage analysis narrows the critical region for oculodentodigital dysplasia to chromosome 6q22-q23.

Oculodentodigital dysplasia (ODDD) is an autosomal dominant condition with high penetrance and variable expressivity. The anomalies of the craniofacial region, eyes, teeth, and limbs indicate abnormal morphogenesis during early fetal development. Neurologic abnormalities occur later in life and appear to be secondary to white matter degeneration and basal ganglia changes.

[Perimesencephalic subarachnoid hemorrhage].

Acute, non-traumatic subarachnoid haemorrhage is usually caused by a ruptured aneurysm. This is a serious condition involving high mortality. Perimesencephalic haemorrhage has recently been identified as a clinical subset of subarachnoid haemorrhage.

Midbrain tremor and hypertrophic olivary degeneration after pontine hemorrhage.

A severe rest tremor arose in a patient's right arm 9 months after a pontine tegmental hemorrhage. Magnetic resonance studies at 4 and 10 months showed residual hemosiderin in the pons and increasing hypertrophic olivary degeneration (HOD) affecting primarily the left olive. The tremor was refractory to pharmacotherapy (clonazepam, propranolol, and levodopa), but was reduced after implantation of a thalamic stimulator device.