Delayed Contralateral Trigeminal Neuralgia After Microvascular Decompression and Postoperative Changes in Venous Outflow

A 66-year-old woman had presented with a 3-month history of left trigeminal neuralgia. She had undergone successful microvascular decompression for right-sided trigeminal neuralgia 8 years previously. To optimize visualization, microvascular decompression for trigeminal neuralgia has been commonly associated with sacrifice of the superior petrosal vein during surgery. The absence of sufficient collaterals can result in most of the posterior fossa venous drainage relying solely on the contralateral superior petrosal vein, leading to subsequent vessel enlargement and a compressive effect on the trigeminal nerve and causing iatrogenic contralateral trigeminal neuralgia. We have provided preoperative and intraoperative images illustrating nicely the adapted postoperative change in venous outflow causing contralateral compression of the trigeminal nerve. Consecutive treatment effects should be carefully considered when offering and performing surgical microvascular decompression.

Combined Hyperactive Dysfunction Syndrome of the Cranial Nerves: Analysis of 37 Cases and Literature Review

BACKGROUND

Hyperactive dysfunction syndrome (HDS) of the cranial nerves, such as trigeminal neuralgia (TN), hemifacial spasm (HFS), and glossopharyngeal neuralgia (GPN), is commonly managed by microsurgical treatment. However, certain patients may present a combination of these syndromes in the neurosurgery department. Here, we aimed to retrospectively assess patients with combined HDS from a single center.

METHOD

Of 1275 consecutive patients with HDS treated at our center between 2007 and 2017, 37 patients with combined HDS were enrolled, and their medical and surgical records were analyzed.

RESULTS

The patients with combined HDS, accounting for 2.9% of all patients with HDS, included 22 patients with bilateral TN, 5 patients with TN-HFS, 8 patients with TN-GPN, and 2 patients with GPN-HFS. A comparison of patients with single and combined HDS indicated a significant difference in the mean age at initial diagnosis (63.57 vs. 56.18 years, P = 0.000) but no such difference in the sex ratio (0.54 vs. 0.59, P = 0.865) or incidence of hypertension (32.43% vs. 24.56%, P = 0.274). In total, 32 microvascular decompression (MVD) procedures were performed in the 27 patients with combined HDS, and repeated MVD was required in 5 patients with bilateral TN. Of the 27 patients who underwent MVD, 25 (92.6%) experienced clinical cure or obvious alleviation.

CONCLUSIONS

Combined HDS involves a group of functional disturbance disorders affecting specific cranial nerves, and it may include TN, HFS, and GPN. In addition to gender and incidence of hypertension, age appeared to be a vital indicator for the development of combined HDS, although this finding was inconsistent in previous studies. MVD appears to be a safe and effective treatment for combined HDS, with a high rate of long-term success.