Osteoid Osteoma


Axenfeld Nerve Loop

A 12-year-old girl was brought by her parents for evaluation of a spot in her eye, which they feared might be an embedded foreign body. She had nominal eye discomfort, which was probably secondary to attempted removal of the object. The child could not recall having dust particles in the eye, and she had no previous eye lesion.

Visual acuity was 20/20 uncorrected. There was no lid swelling and minimal conjunctival injection. A slightly raised, 1.5-mm pigmented lesion was noted (arrow); all other ocular findings were normal. The lesion was suspected to be an intrascleral nerve loop of Axenfeld. The patient was referred to an ophthalmologist who confirmed the diagnosis.

Although Axenfeld nerve loops are fairly common, large loops are rarely seen. When part of the long posterior ciliary nerve that traverses the sclera and loops back to the ciliary body is associated with neurilemmal or connective tissue proliferation, it may form a prominent elevation 4 to 7 mm posterior to the limbus.1 The pigment in the nerve loop may increase over time, and the loop could then be mistaken for a foreign body.2

Intrascleral nerve loops have also been confused with nevi, malignant melanomas, and cysts.3 Slit lamp assessment is essential for correct identification of fixed, pigmented, periocular objects, especially when a foreign body is suspected and attempted removal is unsuccessful.

The family was reassured that the lesion was benign. Regular follow-up with an ophthalmologist was advised. *