The lack of a consistent decrease in gray and white matter density argues against a progressive neurodegenerative process in essential tremor that leads to a substantial decrease in cerebellar gray matter volume. Patients with predominant intention tremor show a relative expansion of gray matter areas involved in higher order visuospatial processing, which might represent a long-term result of adaptive reorganization compensating the higher demands on the visuospatial control of skilled movements in case of trembling.

A) Frequency of Far Lateral Lumbar Disc Herniation: The analysis of pre-operative computer-assisted tomograms and myelograms in a series of 694 operated lumbar disc herniations showed that a far lateral disc prolapse occured in 7% of the cases. Within the group of those far laterally herniated discs 3% of the herniations were predominantly located in the intervertebral foramen, whereas 4% of the protruded discs were mainly situated extraforaminally compressing the spinal nerve in its paravertebral course. B) Surgical Management of Extraforaminal Far Lateral Lumbar Disc Herniation: By March 1988 40 patients had been operated on for an extraforaminal disc protrusion making use of an external microsurgical exposure (in two cases by a transmuscular approach and in 38 cases via an enlarged midline approach). A medium-term follow-up of these 40 patients revealed a substantial clinical relief of pain in 34 cases (85%). Based on these gratifying results we regard the external exposure of the extraforaminally protruded disc as the treatment of choice.

Proton MR spectroscopy ( 1 H-MRS) has been used to assess regional neurochemical brain changes during normal ageing, but results have varied. Exploiting the increased sensitivity at ultra-high field, we performed 1 H-MRS in 60 healthy human volunteers to asses age-related differences in metabolite levels and their relation to cognitive ageing. Sex was balanced, and participants were assigned to a younger, middle, and older group according to their age, ranging from 18 to 79 years. They underwent 7T 1 H-MRS of the ACC, DLPFC, hippocampus, and thalamus and performed a visuospatial working memory task outside the scanner. A multivariate ANCOVA revealed a significant overall effect of age group on metabolite levels in all regions. Higher levels in the middle than the younger group were observed for myo-inositol (mIns) in DLPFC and hippocampus and total choline (tCho) in ACC. Higher levels in the older than the younger group were observed for mIns in hippocampus and thalamus, total creatine (tCr) and tCho in ACC and hippocampus; lower levels of glutamate (Glu) were observed in DLPFC. Higher levels in the older than the middle group were observed for mIns in hippocampus, tCr in ACC and hippocampus, tCho in hippocampus, and total N-acetyl aspartate (tNAA) in hippocampus. Working memory performance correlated negatively with tCr and tCho levels in ACC and mIns levels in hippocampus and thalamus, but not with tNAA or glutamate levels. As NAA and Glu are commonly regarded to reflect neuronal health and function and concentrations of mIns, tCr, and tCho are higher in glia than neurons, the findings of this study suggest a potential in vivo connection between cognitive ageing and higher regional levels of glia-related metabolites.