PubMed · 14375639
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
G J MELOT, R POTVLIEGE. [Fractional encephalography].. https://doi.org/10.1080/17843286.1955.11717335
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
The authors report a 4-year-old girl who developed brain stem glioblastoma. Meningeal irritation was present at onset. Magnetic resonance imaging revealed intracranial and intraspinal leptomeningeal dissemination, which progressed faster than the original tumor. Multiple large cysts developed at the interhemispheric and prepontine cisterns, resulting in progressive obstructive hydrocephalus. The patient survived only 5 months after presentation. Histology was verified by autopsy.
AIMS: The dural and arachnoid hole caused by lumbar puncture needles is a determining factor in triggering headaches. The aim of this study is to assess the dimensions and morphological features of the dura mater and arachnoids when they are punctured by a 22 gauge Quincke needle having its bevel either in the parallel or in the transverse position. METHODS: Fifty punctures were made with 22 gauge Quincke needles in the dural sac of four fresh cadavers using an "in vitro" model especially designed for this purpose. The punctures were performed by needles with bevels parallel or perpendicular to the spinal axis and studied under scanning electron microscopy. RESULTS: Thirty five of the 50 punctures done by Quincke needles (19 in the external surface and 16 in the internal) were used for evaluation. When the needle was inserted with its bevel parallel to the axis of the dural sac (17 of 35), the size of the dura-arachnoid lesion was 0.032 mm(2) in the epidural surface and 0.037 mm(2) in the subarachnoid surface of the dural sac. When the needle's bevel was perpendicular to the axis (18 of 35) the measurement of the lesion size was 0.042 mm(2) for the external surface and 0.033 mm(2) for the internal. There were no statistical significant differences between these results. CONCLUSIONS: It is believed that the reported lower frequency of postdural puncture headache when the needle is inserted parallel to the cord axis should be explained by some other factors besides the size of the dura-arachnoid injury.
OBJECTIVE: To apply a theoretical model to analyse the derangement of cerebrospinal fluid (CSF) dynamics in syringomyelia associated with adhesive arachnoiditis. METHODS: An electrical circuit model of CSF dynamics in the spine was used. With this model, the derangement of CSF dynamics in adhesive arachnoiditis was simulated. The effects of various surgical procedures were then analysed, such as syringo-subarachnoid shunting, subarachnoid bypass, and foramen magnum decompression. RESULTS: When CSF flow in the subarachnoid space was obstructed at a certain point, the pressure inside the spinal cord increased in the segment immediately distal to the blockage. This location of increased pressure corresponded to the preferred site of syrinx formation in adhesive arachnoiditis. Syringo-subarachnoid shunting, subarachnoid bypass, and foramen magnum decompression were all effective at reducing this pressure gradient. CONCLUSIONS: Blockage of the spinal subarachnoid CSF pathway produces a relative increase in the pressure inside the spinal cord distal to the blockage point. Repetitive formation of this pressure gradient then induces CSF leakage into the spinal parenchyma, leading to the formation of syringomyelia. Using this model, alternative surgical procedures could be suggested that might be effective in treating this disease.