PMC7670372_01
a DSA reveals an arteriovenous shunt (arrow) at the level of the thrombosed part of the straight sinus. b Graphic illustration of the cDAVF. The fistula is fed by the tentorial dural arteries (red) and drains through the straight sinus into the median tentorial sinus, supraculminal vein, superior vermian vein, and then into the system of the vein of Galen. Due to the thrombosis (asterisk) of the proximal segment of the straight sinus, missing direct outflow, and arterialization of the system of the vein of Galen with consecutive flow reversion, the fistula causes severe reflux and congestion in the system of the internal cerebral veins. The cDAVF is classified as Cognard type III, Borden type III, and DES-Zurich bridging vein shunt type with direct, exclusive, and strained LVD. SSS, superior sagittal sinus.
cee-0010-0124-g01.jpg
PMC7670372_01_cee-0010-0124-g01.jpg
F1
Due to the thrombosis of the proximal segment of the straight sinus, missing direct outflow, and arterialization of the system of the vein of Galen with consecutive flow reversion, the fistula caused severe reflux and congestion in the system of the internal cerebral veins (Fig. 1a, b). It was thus classified as Cognard type III, Borden type III, and DES-Zurich BVS type with direct, exclusive, and strained LVD (Fig. 1).
a, b Sagittal and axial section of FLAIR-weighted images show a massive progression of the venous congestive edema of both thalami, internal capsule, pallidum and mesencephalon due to the nonoccluded cDAVF. c SWI-weighted images show multiple microhemorrhages within the congested tissue.
cee-0010-0124-g02.jpg
PMC7670372_01_cee-0010-0124-g02.jpg
F2
Sagittal section of T1-weighted MRI TOF with gadolinium before (a) and after microsurgical clipping and complete cDAVF occlusion (b). DSA before (c) and after complete cDAVF occlusion (d).
cee-0010-0124-g03.jpg
PMC7670372_01_cee-0010-0124-g03.jpg
F3
DSA showed complete obliteration of the cDAVF (Fig. 3b, d). During hospitalization, a detailed examination of thrombophilia was performed due to the unexplained thrombosis of the straight sinus.
Sagittal section of FLAIR (a, b) and axial section of T2-weighted (c, d) MRI. The 3-month follow-up MRI displays complete regression of the venous congestion of the Galenic system (b, d) compared to preoperatively (a, b).
cee-0010-0124-g04.jpg
PMC7670372_01_cee-0010-0124-g04.jpg
F4
MRI showed complete regression of the bithalamic edema, internal capsule, hippocampi, pallidum, and mesencephalon (Fig. 4b, d), although the thrombosis of the straight sinus had remained unchanged.