AAO: Intraorbital Surgery Relieves Pain for Some Patients with Trigeminal Neuralgia

NEW ORLEANS, Nov. 13 -- For patients with trigeminal neuralgia with V1 involvement, intraorbital surgery may offer effective pain relief, results of a small case series reported here suggest.Seven of eight patients treated thus far have minimal or no residual pain during follow-up for as long as five years, Susan Tucker, M.D., of the Lahey Clinic in Peabody, Mass., told attendees at the American Academy of Ophthalmology meeting.
Action Points
Explain to interested patients that an alternative form of surgery may provide pain relief in certain types of trigeminal neuralgia.
Emphasize that this surgery has been tried in only a small number of patients with an uncommon form of the condition.
Note that the findings were reported at a medical conference and as a published abstract and should be considered preliminary until they have appeared in a peer-reviewed journal.
Although tried in a restricted patient population, the surgery is highly effective in that group of patients, she said.
"Most of the patients who have had this surgery had tried other therapies without success," said Dr. Tucker. "For those patients, this surgery did what none of the other treatments could do for any length of time: relieve the pain."
Trigeminal neuralgia affects four to five individuals per 100,000. In 20% of cases the origin of the pain involves the ophthalmic division of the trigeminal nerve (V1), which divides into the lacrimal, frontal, and nasociliary nerves. Isolated V1 involvement occurs in only 3% to 4% of the patients, said Dr. Tucker.
Current therapy for trigeminal neuralgia with V1 involvement includes neuroleptic medications, various types of percutaneous procedures (neurectomy via sub-brow incision, glycerol injection, radiofrequency thermal rhizotomy, and balloon microcompression), gamma knife radiosurgery, and microvascular decompression. These treatments often prove ineffective, and some involve significant risks to the patient, Dr. Tucker said.
Alternatively, resection of a large segment of the frontal nerve or its branches within the orbit by means of a skin-crease incision might provide more effective and durable pain relief.
Dr. Tucker reported outcomes for eight patients who have undergone anterior orbitotomy and resection of the supratrochlear and supraorbital nerves. The surgery was performed with general anesthesia or intravenous sedation.
Seven of the eight patients had typical idiopathic trigeminal neuralgia involving branches of the frontal nerve. Five remained pain free during follow-up for as long as 65 months.
One patient had pain recurrence two years after surgery, and one patient had 90% improvement but residual pain across the bridge of the nose. The eighth patient had atypical pain, which did not improve after surgery.
Reviewing the pros and cons of the surgery, Dr. Tucker said the advantages include direct access to the frontal nerve and its branches, a short operating time (typically 15 to 20 minutes), and no risk of corneal anesthesia because the nasociliary branch is not affected.
Drawbacks of the procedure include its applicability to a restricted patient population, uncertainty about long-term success, a potential for transient ptosis, and numbness in the frontal nerve distribution.
The procedure might be useful for management of other types of chronic pain, particularly patients with first-division post-herpetic neuralgia, Dr. Tucker suggested. She has identified some potential candidates for the surgery but has yet to perform the operation in a patient with post-herpetic neuralgia.
Dr. Tucker had no financial disclosures.Primary source: American Academy of OphthalmologySource reference: Tucker SM, "Intraorbital surgery for trigeminal neuralgia" AAO Meeting 2007; Abstract PO126