Supraorbital neuralgia
Trigeminal neuralgia (TGN) may present with pain in the distribution of the supraorbital nerve; however, the supraorbital nerve may be involved in supraorbital neuralgia (SON), a distinct syndrome with different clinical characteristics 1)
Epidemiology
SON is a rare condition slightly more common in women, with onset typically 40–50 years of age 2)
Etiology
SON may be:
1. primary (no identifiable etiology): these cases lack any sensory loss
2. secondary (e.g., due to trauma to the area, or resulting from chronic pressure such as with wearing swim goggles): more common than primary SON. Most cases remit within one year 3) with the elimination of the offending pressure
Clinical features
Supraorbital neuralgia is a rare disorder clinically characterized by the following triad:
1) Forehead pain in the territory supplied by the supraorbital nerve, without side shift.
2) tenderness on either the supraorbital notch or trajectory of the nerve; and 3) absolute, but transitory relief of symptoms upon supraorbital nerve blockade. The pain presents with a chronic or intermittent pattern. In addition, there may be signs and symptoms of sensory dysfunction (hypoesthesia, paresthesia, and allodynia), and typical “neuralgic features” (lightning pain and exteroceptive precipitating mechanisms). However, sensitive and neuralgic features are not constantly present and seem to be more frequent in the secondary, usually post-traumatic, forms 4).
Differential diagnosis
1. Migraine: suggested by nausea, vomiting, and photophobia
2. Associated autonomic activity is rare with SON, and should prompt consideration of cluster headache or SUNCT
3. Trigeminal neuralgia : typical TGN features lacking in SON include characteristic triggers and pain consisting exclusively of paroxysmal/ultra-brief electric-shock–like pain
4. Hemicrania continua: continuous unilateral pain that tends to be located more posteriorly and is absolutely responsive to indomethacin 5)
5. Trochleitis: inflammation of the trochlea/superior-oblique muscle complex, may mimic supratrochlear neuralgia with the pain of the medial upper orbit extending a short distance to the forehead 6)