Stefan Felber

Brain activation patterns during a verbal fluency test: a functional MRI study in healthy volunteers and patients with schizophrenia

FMRI was used to study cortical activation patterns in nine healthy male subjects and nine high-functioning male schizophrenia patients during a letter verbal fluency task. Both groups showed similar patterns of activation, however, in controls the activation was primarily in the left broca area, while for schizophrenia patients, it was more bilateral. These data indicate that high-functioning schizophrenia patients show a reduced language lateralization of the frontal cortex compared to healthy controls.

Hippocampal volume reduction in male schizophrenic patients

Using magnetic resonance imaging of the brain, we examined volumetric measurements of total brain, hemispheres, lateral ventricles and the hippocampus/amygdala complex in male subjects (41 first-episode schizophrenics, 30 chronic schizophrenic patients and 32 healthy controls). We found significantly smaller total brain size in the chronic schizophrenic group, significantly larger lateral ventricles in both patient groups and hippocampal volume reduction bilaterally in first-episode patients (-13.2% left, -12.05% right) and chronic patients (-10.6% left, -10.5% right) compared to controls--irrespective of diagnostic subtype, family history for psychiatric diseases, psychopathology, duration of illness or age at onset.

Vascular endothelial growth factor (VEGF) is elevated in brain tumor cysts and correlates with tumor progression

Abstract Vascular endothelial growth factor (VEGF), a key regulatory protein in neoangiogenesis, is strongly expressed in a variety of primary brain tumors, particularly malignant gliomas. In previous studies, high levels of VEGF were also reported in tumor cysts of glioblastomas. Using an ELISA method we measured the concentration of VEGF in matched samples of aspiration fluid from tumor cysts and serum. Samples were collected from 14 patients with primary brain tumors of various histology (six glioblastomas, one protoplasmatic astrocytoma, two pilocytic astrocytomas, one ependymoma, one meningioma, and three craniopharyngiomas) and two patients with solitary cystic brain metastases from adenocarcinomas of the lung. Aspiration fluids of tumor cysts from all patients revealed high VEGF levels ranging between 882 and 1,263,000 pg/ml, which were 2 to more than 2,000 times higher than the corresponding serum levels. Maximum VEGF levels were detectable in cyst fluids from recurrent glioblastoma. Serum VEGF levels ranged between 125 and 716 pg/ml and did not differ from serum levels in 145 healthy volunteers. In a single patient with metastatic lung cancer the concentration of VEGF in serum and cyst fluid was determined during disease progression. During 60 days of follow-up VEGF concentrations in the cyst fluid collected by puncture of an Ommaya reservoir increased 650-fold, while serum levels remained rather constant. These findings indicate that immunoreactive VEGF is produced at the tumor site and abundantly released into the cyst fluid of primary and metastatic brain tumors. Interestingly, this abundant local release is not reflected in serum VEGF levels, even in the case of very high VEGF concentrations in tumor cysts. Thus, VEGF may be biologically relevant for the formation of tumor cysts in brain tumors and correlates with local disease progression.

Progressive multifocal leukoencephalopathy presenting with an isolated focal movement disorder

Progressive multifocal leukoencephalopathy (PML) is a rare but fatal papovavirus infection of the central nervous system predominantly affecting immunocompromised patients. Although the basal ganglia circuitry may be involved in the pathology of PML, movement disorders are exceedingly rare as presenting symptoms and have not been described as isolated features in such patients. We report a previously healthy, immunocompetent 24‐year‐old woman with histologically proven PML who presented with a focal movement disorder of the left arm as an isolated symptom for many months before diagnosis.

Spontaneous collapse of posttraumatic syringomyelia : serial magnetic resonance imaging

The case of a 30-year-old man with posttraumatic syringomyelia involving the cervical and upper thoracic spine is reported. The patient was followed clinically and with magnetic resonance (MR) imaging over a 3-year period. Spontaneous complete remission of the syrinx-related symptoms correlated with a partial collapse of the syrinx, as proved by serial MR imaging.