Nerve Block for Supraorbital Neuralgia Effective for Both Diagnosis and Treatment

Approximately 8% of subjects in a recent thyroid eye disease study population of 1126 developed symptoms of supraorbital neuralgia, often describing the pain as burning, throbbing, or similar to a nail “driven through the head.” Supraorbital neuralgia (SON) pain is sometimes misdiagnosed, underreported, and management options are not yet widely established, according to researchers who completed the analysis.

Of the total participants, 946 (84%) reported pressure or ache behind or around at least 1 eye. In 91 subjects, the more distinct SON-type symptoms were debilitating — they reported pain radiating laterally across the supraorbital rim, moving upward on the forehead, or lingering behind the eye. All participants with suspected SON received a supraorbital nerve block, and 3 were also given zygomaticotemporal, zygomaticofacial, or supratrochlear nerve blocks. Remarkably, 100% felt relief of discomfort within 15 minutes, and this easing of symptoms continued past 24 hours, according to the investigators. 

In addition to anesthetic nerve block, 2 effective treatment options included either orbital decompression surgery or a neuroleptic combination of gabapentin, dilantin, and tegretol. Corticosteroids modestly reduced pain, and nonsteroidal and vasoactive migraine medications were least helpful, researchers added.

Investigators theorize the onset of SON is caused by a combination of hydrostatic-compressive pressure on the frontal nerve and an intrinsic neurogenic process. Study subjects whose thyroid eye disease reactivated were more likely to have SON than those in a primary activation stage. “Thus, one might wonder whether there is a mechanistic connection between the development of SON and reactivation,” they added.

SON may also point to a greater risk for orbital decompression surgery. Overall, this surgery was indicated by proptosis and exposure keratopathy (57%), optic neuropathy (34%), pain (7%), glaucoma progression (2%), and aesthetics (0.04%). “Patients with SON-type pain were nearly twice as likely, 88 of 91 (97%) to undergo orbital decompression in the 7 years of study compared to those without, 496 of 1,035 (48%)” according to  investigators. “Even if the 30 patients in whom the primary indication for decompression was pain are excluded, the decompression rate among patients with SON was 64%, still different from those without.”

The research period comprised a 4-year retrospective analysis of patients at a large tertiary thyroid eye disease referral practice in the United States.Investigators used 3 standard rating systems; the vision, inflammation, strabismus, and appearance (VISA), clinical activity score (CAS), and European Group of Graves’ Orbitopathy (EUGOGO). Researchers found no association between SON-type pain and participant’s amount of exophthalmos, gender, age, smoking status, duration of active phase disease, or size of extraocular muscles on CT scan. Those with SON pain did not differ significantly from the total study population in their average CAS, VISA, or EUGOGO scores.

Limitations involved a possible under- or over-estimation of SON in thyroid eye disease due to the rigorous inclusion criteria, or disease stage of the referred study population. The placebo effect was also not considered. Further, in the tertiary clinic, patients with optic neuropathy were offered orbital decompression surgery early on, precluding improvement of SON on its own.

Reference

Patrinely J, Hamilton K, Parke R, Patrinely, R, Soparkar C. Supraorbital neuralgia associated with thyroid eye disease. Ophthalmic Plastic and Reconstructive Surgery. Published online June 17, 2020. doi: 10.1097/IOP.0000000000001762.