gms | German Medical Science

At long-term follow-up after microvascular decompression (MVD), approximately 30% of patients with trigeminal neuralgia develop a pain recurrence or do not respond to this procedure at all. Some of them can be treated by renewed surgery. However, the best treatment of “failing” patients is controversial. We introduce the long-term results of 10 patients in whom a neuromodulation of the trigeminal nerve was performed in combination with renewed MVD.

The series includes 7 patients of recurrent idiopathic trigeminal neuralgia and 3 patients with neuralgia due to multiple sclerosis. All patients underwent between one and four previous MVD-procedures. After reexploration of the trigeminal nerve over the distance from the root entry zone to the periphery, a stimulation electrode (Medtronic, DBS) was placed in Cavum Meckeli and externalised for later test-stimulation. If there was a positive response to test-stimulation a nerve stimulator (Medtronic, Itrel) was implanted subcutaneously and connected to the stimulation electrode. Follow-up examination was performed at a mean of 4 years after surgery and focussed on the pain control and present use of stimulation as well as medical treatment.

After renewed MVD + Cavum Meckeli electrode-implantation 5 patients reported a complete pain relief. Therefore a test-stimulation was not necessary and the electrode was transferred in a subcutaneous pouch for possible future use. In 5 cases, the patients reported a remarkable pain-relief towards test-stimulation. In those a stimulator was implanted a few days after MVD. A delayed test-stimulation and stimulator implantation after pain recurrence was done in 3 patients 10, 24 and 48 months later. At long-term follow-up, 7 out of 8 patients supplied with a stimulator reported a good pain control due to regular use of stimulation. In one patient a breakage of the stimulatory wire had occurred and is planned to be repaired. In the remaining two patients who did not undergo test-stimulation, one is still free of pain and the other refused a test-stimulation so far. Apart from wire-breaks, which occurred in 4 patients and were repaired in 3 of them, no other complications were seen.

The described method of a simultaneous implantation of a stimulation-electrode into the Cavum Meckeli together with a reexploration and MVD of the trigeminal nerve seems to be helpful in patients with idiopathic trigeminal neuralgia non-responding to MVD.