Interdural dissection for superficial Sylvian vein tightly adhering to dura mater: Technical case report

Dissection of the superficial Sylvian vein is a key step to achieve a wide surgical corridor without interfering with normal venous flow, but can be hampered by tight adhesion to the dura mater. In this situation, dissecting the thin venous wall from dura mater is challenging. Here we examine the utility of interdural dissection for preserving and detaching superficial Sylvian vein adhering tightly to dura mater. We present a surgical case of unruptured middle cerebral artery aneurysm with tight adhesion of the superficial Sylvian vein to the dura mater, demonstrating the utility of an interdural dissection technique for detaching the vein from dura mater. During Sylvian fissure dissection, the superficial Sylvian vein was tightly adherent to the inner layer of the dura mater, creating a wide surgical corridor allowing meticulous aneurysm dissection. To dissect the Sylvian fissure widely, the superficial Sylvian vein was dissected from the dura mater by dissecting the interdural layer of dura mater instead of dissecting between the thin venous wall and dura mater. Finally, a sufficient surgical corridor was achieved, allowing successful aneurysm obliteration. This interdural dissection technique is useful for preserving and detaching the superficial Sylvian vein tightly adhering to dura mater.