Orbital fine-needle aspiration biopsy.

Fine-needle aspiration was used as a primary orbital diagnostic technique in 156 patients. A 20-mm syringe, a 22-gauge, 3.75-cm needle, and a plastic pistol grip were used. Local anesthetic was not necessary. When the needle is in the lesion, small to-and-fro movements with a minimum of angulation are helpful. The aspirate is spread on slides fixed with alcohol. Positive cytologic identification was made in 125 of 156 cases. Commonly identified lesions included metastatic carcinoma, inflammatory lesions, and lymphoid lesions. Small posterior apical lesions are difficult to aspirate, but are often the most rewarding diagnostically. Fine-needle aspiration was not successful in tumors of fibrous consistency, in those located in the orbital apex, or in lymphocytic lesions with specimens inadequate for diagnosis.