The patterns of symptoms exhibited by a total of 48 cases of basal meningiomas were studied. The cases included 21 male and 27 female patients. The youngest subject was a boy of 11 and the oldest was a 72 year-old man. Distribution of tumor site were 7 in the olfactory groove, 12 in the suprasellar region, 18 in the sphenoid ridge, 3 in the base of the middle fossa, 8 in the posterior fossa, the last including only those that had attachment at the skull base. Operative grades I, II, III, IV and V (according to Simpson's grading) were applied to 1, 13, 15, 17 and 2 cases respectively. Histological findings of the resected tumors were 39 meningothelial, 6 fibrous and 3 angioblastic. Recurrence was observed in 16 cases out of 48 (33.3%). The site of 16 recurrences were 1 olfactory groove, 4 suprasellar region, 6 sphenoid ridge, 2 base of the middle fossa and 3 posterior fossa. The preoperative and post-operative symptom patterns were comparatively studied from the aspects of clinical symptoms, neuroradiological findings and operative findings.
The tumors were classified into three types according to its growth pattern. A type: mainly in the intracranial cavity, B type: mainly in the skull, and C type: the mixture of the two. All of the seven cases of tumor in the olfactory groove belonged to the A type. A single recurrent case belonging to this group, however, was found to be the B type in a second operation. The twelve suprasellar tumors were first classified as eleven A types and one C type. All of the four recurrences from this group belonged to the A type at the time of the first operation. At the time of recurrence, however, they were distinguished as three A types and one C type. The eighteen sphenoid ridge tumors were first classified as nine A types, one B type and eight C types. The six recurrences were one A type, two B types and three C types at time of the first operation, but later found to be one A type, one B type and four C types. The three tumors at the base of the middle fossa were equaly distributed among the A, B and C types at the first operation, however, the two recurrences were one each of B type and C type. The eight posterior fossa tumors were first classified as two A types, two B types and four C types at the first operation. All the three recurrences belonged to the C type but on a closer look the intracranial proliferation was greater compared to the penetration into the bone tissue.
The clinical symptoms can be summarized as follows. Multiple cranial nerve lesions and growth of intraosseous tissue were more frequent in the sphenoid ridge meningiomas, while recurrence as intracranial mass indicating increased CSF pressure was more frequent more in the posterior fossa. Nasal liquorrhae was observed in two of the recurrences of which one was in the olfactory groove. For the latter, nasal liquorrhae was the initial symptom of recurrence. Visual disturbance was mostly indicated in tumors in the suprasellar resion and the sphenoid ridge, and the post-operative exacerbation was rapid in the recurrent cases.
Follow-up results of the 48 basal meningiomas in the postoperative periods of 8 months to 14 years were: 4 excellent (8.3%), 12 good (25.1%), 7 fair (14.5%), 6 poor (12.5%), 13 deaths (27.1%) and lost 6 (12.5%), The 16 recurrences were 3 good, 7 fair and poor inclusive, and 6 deaths.
View full abstract