Ultrasound-guided supraorbital nerve block should be considered in the treatment of a variety of painful conditions in areas subserved by the supraorbital nerve, including supraorbital neuralgia, supraorbital nerve entrapment, swimmer’s headache, and pain secondary to herpes zoster. Pulsed radiofrequency treatment can be applied to the supraorbital nerve for sustained pain relief in patients who get a positive response to the initial local anaesthetic block.
The supraorbital nerve is formed from the fibers of the frontal nerve, which is the largest branch of the ophthalmic nerve. The frontal nerve enters the orbit via the superior orbital fissure as it passes anteriorly beneath the periosteum of the roof of the orbit. The frontal nerve gives off a larger branch, the supraorbital nerve and a smaller medial branch, the supratrochlear nerve. Both exit the orbit anteriorly. The supraorbital nerve sends fibers to the vertex of the scalp and provides sensory innervation to the forehead, upper eyelid, and anterior scalp. The supraorbital nerve is a pure sensory nerve.
Supraorbital nerve block is useful in the diagnosis and treatment of a variety of painful conditions in areas subserved by the supraorbital nerve, including:
The procedure is usually done on an outpatient basis. Ultrasound can reliably be used for infiltration of the supraorbital nerve. This will improve the safety as well as the diagnostic utility of the procedure. A discontinuity in the supraorbital ridge (the supraorbital notch) is identified by ultrasound examination. Colour Doppler can be utilized to identify the supraorbital artery, which exits the supraorbital foramen along with the supraorbital nerve.
Local anaesthetic and steroid can be injected under real-time ultrasound guidance targeting the supraorbital nerve at the supraorbital notch. A positive response confirms the diagnosis of supraorbital neuralgia and can provide therapeutic benefit lasting weeks to months.
Pulsed radiofrequency treatment can be applied to the supraorbital nerve in patients who get a positive response to the initial local anaesthetic block. Pulsed radiofrequency can provide sustained pain relief in patients with chronic supraorbital neuralgia or supraorbital nerve entrapment.
Injections are generally avoided in patients with systemic infection or skin infection over puncture site, bleeding disorders or coagulopathy, allergy to local anaesthetics or any of the medications to be administered.
Complications are rare, particularly if injections are performed under ultrasound guidance. Severe allergic reactions to local anaesthetics are uncommon. Post-procedural pain flare-up can occur in some patients especially if steroids are used in the injection. Because of the proximity of the supraorbital artery, post block ecchymosis and hematoma formation can occur even when the procedure is performed under ultrasound guidance.