PMC

The variety of dural venous channels. Any part of the dura can be a venous channel, supra- or infratentorial. There is nothing particularly unique about a tentorial sinus except for the increased frequency of dural venous channels there. 1) Dural venous channel (tentorial sinus group) receiving the basal vein; 2) Dural venous channel (tentorial sinus group) receiving the inferior cerebellar vein; 3) Dural venous channel receiving the vein of Labbe; 4) Dural venous channel (falcine sinus group) receiving a parieto-occipital vein; 5) Dural venous channel (parietal) receiving either a medial or lateral parietal vein such as the vein of Trolard; 6) Dural venous channel (venous lake) receiving the Rolandic/Trolard group of veins; 7) Dural venous channel receiving the superficial Sylvian group of veins. Together with the Labbe dural channel (3 above), these drain into the sigmoid sinus.

Surgical procedure of fat patch with an artificial dural graft. (A) Ventral dural deficit and spinal cord herniation; (B) laminectomy is performed; (C) midline dorsal dural opening is made, and the herniated portion of the spinal cord is repositioned; (D) fat graft is placed into the cavity outside the dural defect; (E) artificial dural graft is placed covering the dural deficit; (F) dorsal dural opening is sutured along with the dural graft.

Typical dural arteriovenous fistula (A) and three distinct patterns of fistulous drainage (B,C,D).
A) Typical dural arteriovenous fistula (DAVF) consists of feeding arteries, arteriovenous shunts located within the dural leafs of the major sinus, and fistulous draining veins initially running within the dural leafs of the sinus and then draining into the involved sinus.
B) Extra-sinus fistulous drainage. Portions of the arteriovenous shunts are located in the dura matter or the tentorium, and the embolizable fistulous drainage, separate from the major dural sinus, drains into the sinus lumen.
C) Intramural fistulous drainage. Portions of the arteriovenous shunts are located within the dural leafs of the major sinus, and the embolizable fistulous drainage located within the dural leafs and separate from the major dural sinus lumen, connects the major sinus lumen. The lumen of the major sinus is not strongly associated with stenotic or pathological changes.
D) There are several lumens inside the major sinus, implying differences in the parts of arteriovenous shunts, in the number of separate lumens, in the haemodynamic relationship between the fistulas and the normal venous outflow.

A: Photomicrograph showing thick fibrous tissue (arrowhead), with a slight infiltration of lymphocytes in the control (black arrow; dural defect, white arrow; dural edge, original magnification ×200). B: Showing mixed inflammatory cell infiltration (arrowhead) surrounding the fibrin glue (black arrow; dural defect, white arrow; dural edge, original magnification ×200). C: Indicating fibroblastic activity (arrowhead) around the gelatin glue (black arrow; dural defect, white arrow; dural edge, original magnification ×400).