BACKGROUND

The cause of trigeminal neuralgia (TN) is vascular compression of the trigeminal root. The last one is also found on intact side and in people without TN. Magnetic resonance imaging (MRI) reveals vascular compression, root deformity and atrophy, as well as localization of neurovascular conflict. To assess significance of MR signs of vascular compression, we compared appropriate data with intraoperative findings.

MATERIAL AND METHODS

Preoperative MRI-based measurement of length (A), width (B) of trigeminal root and distance between brainstem and compression point (C) was performed in 105 patients with TN (51 women and 54 men) aged 56 (22—82) years.

RESULTS

Compression by superior cerebellar artery was detected in 69 cases, anterior inferior cerebellar artery — 6, both arteries — 9, artery and veins — 17, vein alone — 4 cases. Unilateral vascular compression was present in all cases, on intact side — in 31.4% of patients. On the side of trigeminal neuralgia, vessels were localized 1.56 mm (0.3—6.5 mm) away from the brainstem. Compression points were localized at a distance of less than half of nerve root width in 32.4% of cases, 0.5 — 1 width — 59%, 1.5 widths — 2.9%, 1.8—3.5 widths — in 5.7% of cases. On the intact side, vessels were localized 3.48 mm away from the brainstem (0.8—8.7 mm).

CONCLUSION

On the side of trigeminal neuralgia, vessels are localized away from the brainstem at a distance corresponding to trigeminal root width, and distal compression is rare. TN predominantly accompanies proximal vascular compression, and long length of glial segment of trigeminal root may underlie TN in distal compression.