Laura, MRI CANNOT eliminate a nerve compression. On the order of10% or more of all MVD operations discover a previously unseen compression during the exploration phase.
As for "nerve combing", it was a new term for me. The procedure appears to comprise a gentle linear separation of the nerve from surrounding tissues, though I need to do more research to confirm this.
The following abstracts from the US National Library of Medicine appears to be highly pertinent:
"The long-term outcome of nerve combing for trigeminal neuralgia".
Jie H, Xuanchen Z, Deheng L, Kun G, Fengyang X, Xiang C, Xiaoting W, Guangxin Z, Yiqing L.
The purpose of our study was to describe and evaluate the long-term clinical outcome of nerve combing for idiopathic trigeminal neuralgia (TN) with and without vascular compression.
The study included 60 trigeminal neuralgia patients, 28 of which (Group A) had no visible vascular compression intraoperatively and 32 of which (Group B) had trigeminal nerve root entry zone (REZ) compressed by vascular structure. All patients were considered medical failures prior to the surgeries. All of them underwent trigeminal nerve combing. The following outcome measures were assessed: pain relief, recurrence, complication and time to pain relief.
The median duration of follow-up was 52 months (range 48-96 months) in group A and 56 months (range 48-96 months) in group B. Excellent relief and good relief were noted in 23 patients (82.1 %) and two patients (7.1 %) from group A, respectively, and in 20 (62.5 %) and eight patients (25 %) from group B. The major complication of both groups was facial numbness. And the total complication rate was 15.8 % in group A and 18.8 % in group B. Recurrence was found in one patient in group A and in two in group B by the end of follow-up.
Trigeminal nerve combing is effective in treating TN, but has a much higher pain relief rate in patients without vascular compression than those with vascular compression.
Neurol Res. 2013 Mar;35(2):187-92. doi: 10.1179/1743132812Y.0000000132. Epub 2012 Dec 17.
Microvascular decompression treatment for post-Bell's palsy hemifacial spasm.
Li X, Zheng X, Wang X, Li B, Ying T, Li Y, Li S.
This retrospective study is to explore the clinical features and surgical outcomes of the patients who suffered from hemifacial spasm preceded by Bell's palsy.
Seventeen patients with post-Bell's palsy hemifacial spasm underwent microvascular decompression surgery. A 3D-TOF-MRA examination was performed pre-operatively to confirm the existence of offending vessels around the facial nerve. Abnormal muscle response was monitored during operation. The results of spasm resolution and post-operative complications were assessed.
During operation, offending vessels were found and transposed in 15 patients. For the other two patients in whom offending vessel was absent, the facial nerve was treated by combing. The results of spasm resolution were 'cured' in 12 (70·5%) patients, 'improved' in 2 (11·8%) patients, 'fair' in 2 (11·8%) patient, and 'failed' in 1 (5·9%) patient. The complications included transient hearing loss in one case, and deterioration of facial weakness in two cases.
Vascular compression may be an etiological factor of post-Bell's palsy hemifacial spasm, and microvascular decompression is an effective treatment to this disorder.