Dandy's vein decompression for trigeminal neuralgia: A rare venous conflict causing intractable facial pain.

Background: Trigeminal neuralgia (TN) is predominantly caused by arterial compression of the trigeminal nerve; however, venous conflicts, particularly involving Dandy's vein and the superior petrosal sinus (SPS), represent an uncommon but significant etiology.

Case description: We report a case of a 40-year-old female suffering from debilitating right-sided facial pain due to a rare "scissor effect" produced by the superior petrosal sinus and Dandy's vein (vein of the cerebellomesencephalic fissure) compressing the trigeminal nerve. Surgical decompression was performed by interposing autologous skeletal muscle wrapped with Surgicel between the conflicting venous structures and the nerve. The patient achieved complete pain relief without neurological deficits.

Conclusion: This case underscores the importance of recognizing venous causes of TN and highlights the effectiveness of Dandy's vein decompression.