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Fig. 9.11 Case 9. Preoperative axial (a) and sagittal (b)
T1-weighted magnetic resonance images with gadolinium
showing the posterior type of tentorial meningioma.
Preoperative CT venography shows occlusion of the
straight sinus and left transverse sinus, although venous
flow from the superior sagittal sinus to the right transvers
sinus is preserved (c). Postoperative axial (d) and sagittal
(e) T1-weighted magnetic resonance images with gado-
linium show total resection of the tumor. After craniotomy,
the tumor, superior sagittal sinus, and right transverse
sinus are exposed (f). The left transverse sinus and tento-
rial edge are cut at the lateral and anterior margins of the
tumor (g, h). The cerebellar surface is peeled from the
torcular Herophili (i). Most of the tumor is resected with
no residual tumor around the torcular Herophili (j). After
anastomosis between the right transverse sinus and supe-
rior sagittal sinus using a saphenous vein graft is per-
formed (k, l), the tumor is totally removed (m)H. Morisako et al.