gms | German Medical Science

Objective: Microsurgical approach for the treatment of trigeminal neuralgia (TN) is clearly characterized by microvascular decompression (MVD) or partial sensory rhizotomy (PSR) in selected patients respectively. Arterial compression is generally accepted as a cause of TN whereas venous compression might be underestimated. The following study will present our experience and results. Whether endoscopic-assistance is of benefit in that matter or not is additionally discussed in this study.

Method: The prospectively collected database revealed 98 patients treated for TN from November 2000 until October 2012. 101 surgical procedures were performed in these patients. The surgical approach included MVD [91] and PSR [10]. The cause of TN was arterial in 57 cases, venous in 19, arteriovenous in 7 and no compression was expected in 10 patients. In 8 patients a vascular compression was suspected on prior MR imaging that could not be confirmed during surgery. Endoscopic-assistance was used in 89 procedures and included inspection after primary microsurgical dissection of the trigeminal nerve and surrounding arachnoid membranes and finally after MVD.

Results: An immediate or 90% pain relief after MVD caused by venous compression was observed in 15/19 patients (78,9%). After PSR 8/10 patients reported absent pain (80%). 4/8 patients without any vascular compression reported an improvement of pain after surgery for unknown reason (50%). MVD due to arterial or arteriovenous compression was successful in 53/64 patients (82,8%). Two patients developed recurrent pain and underwent successful re-surgery within two years after primary MVD (2%). Endoscopic-assisted inspection revealed 19 unexpected conditions of compressing vessels witch could not be visualized by microscopic view only (21,3%). Overall mean follow up was 46,2 months (range: 0–143 months). Transient complications were observed in 16,8% including partial hearing loss, hypesthesia, dizziness, meningitis or CSF fistula. In another patient partial hearing loss was permanent (1%). No mortality was observed.

Conclusions: The success rate of MVD regarding arterial involvement is similar compared to the literature (82,8%). Venous compression in TN demonstrated good results after MVD in 78,9%. Endoscopic-assisted MVD is very useful to locate compression sites along the trigeminal nerve (21,3%) that might be missed under microscopic view especially in the cases with a prominent suprameatal tubercle.