Search results for "Leptomeninges"
showing 2 items of 2 documents
Do spinal meningiomas penetrate the pial layer? Correlation between magnetic resonance imaging and microsurgical findings and intracranial tumor inte…
1997
OBJECTIVE: To study the relationships between spinal dura-arachnoid and tumor-cord interfaces in spinal meningiomas and to investigate whether a disruption of the pial layer and penetration of the tumor in the spinal cord occurs. METHODS: Fifteen patients with histologically proven meningiomas underwent magnetic resonance imaging (MRI) preoperatively. All patients underwent microsurgery. The histological characteristics of the tumors were compared with MRI and microsurgical findings. RESULTS: At surgery, the peritumoral hypointense rim revealed by MRI in 10 of 15 patients corresponded to a well-defined cerebrospinal fluid-containing space confined between the outer arachnoidal layer and the…
Leukodiapedesis and leukocyte migration in the leptomeninges and in the subarachnoid space.
1981
Pleocytosis in cerebrospinal fluid and infiltration of the leptomeningeal tissue have been studied after injection of ferritin into the subarachnoid space (SAS) of cats. The most important source of granulocytes in the leptomeninges are the relatively large veins of the pia mater, which have very thin walls. Passing between the lining cells of the pia mater the granulocytes leave the connective tissue space of the pia mater and reach the SAS. Leukodiapedesis has also been observed in veins crossing the SAS. During this process, gaps between the lining cells of the perivascular leptomeningeal sheath may develop. There are two possible ways for the granulocytes to pass from the vascular pia m…