Abstract
Abstract: :
Purpose: Diagnostic fine needle aspiration biopsy(FNAB) is a critical tool in the management of intraocular lesions. Standard surface aspiration and intralesional cutting techniques have technical limitations related to the size and configuration of the bevel aperture which may limit the size of lesions possible for study and may lead to potential complications. To address these limitations we propose the use of an unbeveled aperture smaller in maximal transverse dimension. It allows for apposition of the tip to smaller and thinner lesions while minimizing undesired aspiration of aqueous humor. The ability to work at the tumor surface allows for greater flexibility in selecting an approach, decreases the chance of cutting intralesional vessels and allows for direct visualization of tissue aspiration. Greater safety would also result from the absence of a sharp instrument in the eye. We present clinical and experimental studies of a new technique for FNAB using a small port blunt cannula directly apposed to the lesion for the biopsy of intraocular tumors.Methods: In clinical cases of iris lesions in which standard FNAB failed to provide an adequate specimen due to small tumor size or hypervascularity small port technique was employed. A blunt 27-gauge cannula attached to a non-Luer lock syringe was inserted through the existing corneal wound, and the tip was apposed to the surface of the mass. Aspiration was performed until material was seen entering the cannula. The aspirated material was placed on slides, alcohol fixed and stained with H&E;. Intraoperative review with a cytopathologist demonstrated diagnostic material.Prospective comparative studies: Residual tissue from freshly excised non-fibrous orbital tumors underwent FNAB by 25-gauge needle and small port technique. Air dried and alcohol fixed specimens were prepared, stained with H&E; and examined in a masked manner for the presence and quality of obtained tissue.Results: In all clinical cases, the small port technique provided an adequate tissue sample when the standard technique provided a non-diagnostic specimen.Comparative analysis studies: When compared prospectively with the 25-gauge needle in aspiration of excised tumor tissue, both methods provided equivalent diagnostic material. Conclusions: Because small port FNAB of visible intraocular lesions using a blunt tipped cannula provides equivalent diagnostic material with greater safety and applicability, it may be considered a preferred technique for FNAB of these lesions. In addition, it may have similar advantages in FNAB of choroidal masses.
Keywords: pathology techniques • oncology • iris