Fine needle aspiration biopsy in orbital lesions.

PURPOSE. The study was performed to evaluate the efficacy of fine needle aspiration biopsy (FNAB) in orbital lesions. METHODS. Seventeen patients with orbital masses who had been fully investigated by non-invasive techniques participated in this study. FNAB was performed by standard technique, as an outpatient procedure, with ultrasound guidance in lesions posterior to the equator. A trained cytologist analysed all the smears. RESULTS. Specific results were obtained in 14 of the 17 (82%) patients studied by FNAB. Ten cases were neoplastic (8 malignant and 2 benign), 3 were inflammatory and 1 was a case of histiocytosis X. In 3/17 cases the results were non-specific. These were treated as pseudotumours and responded well to systemic steroids. In 7 cases the clinical and radiological diagnosis was confirmed by FNAB. Non-invasive investigations like USG, CT and MRI, however, failed to provide accurate diagnosis in the other 7 (41%) cases. In these patients, FNAB yielded a pathological diagnosis (histiocytosis X, cryptococcosis, non Hodgkin's lymphoma, adenocarcinoma, pleomorphic adenoma, Schwannoma and cysticercosis), helping us to modify treatment with an excellent response. No significant complications were encountered following the aspiration biopsies. CONCLUSION. FNAB proved to be a reliable method for distinguishing between malignant and non-malignant lesions. It was found to be rapid, accurate, cost-effective, safe and a valuable addition to ultrasound, CT scan and MRI in the diagnosis of orbital lesions. This tool may help in avoiding a traumatic surgical intervention.