Purpose:
Fine needle aspiration biopsy of uveal melanoma is being increasingly performed for prognostication purposes. Standard 25 G needle has a long bevel (1.5 mm) and lacks any surface markings to judge depth of penetration. We evaluated a custom designed prototype 25 G needle with short bevel (0.25 mm) with millimeter marking on the outer surface (Geuder, Heidelberg, Germany) for fine needle aspiration biopsy of uveal melanoma.
Methods:
12 eyes with clinical diagnosis of uveal melanoma were included in the study. In all cases, trans-scleral approach was used to perform the aspiration biopsy with a standard 25 G needle and the prototype needle. Aspiration biopsy was performed after enucleation (10 cases) and during brachytherapy (2 cases) (Figure 1). Aspirated samples were rinsed into CytoLyt® preservative solution (7 cases) or a non-haemolytic fluid (AutoCyte®) (5 cases). For each case, one vial contained the sample from 25 G needle and the other vial contained the sample from prototype needle. After processing, the cytological slides were evaluated in a blind fashion by a single cytopathologist for the presence of diagnostic melanoma cells. Further, cellularity was scored semiquantitatively, as 0 through 3+, with 0 being acellular. In addition, a side by side cellularity comparison was also performed.
Results:
The mm surface markings on the prototype needle facilitated precise depth penetration in all 12 cases. FNAB aspirates were diagnostic only in 8 cases (67%) whereas all aspirates (100%) with the prototype needle were judged as diagnostic. Moreover, cellularity of the aspirate was greater with the prototype needle in 10 cases (83%) and equivalent to the standard 25 G needle aspirate in the remaining 2 cases (17%).
Conclusions:
Custom designed prototype 25 G needle with short bevel and mm surface marking offers precision in depth penetration and provides more cellular aspirates when compared with standard 25 needle for aspiration biopsy of uveal melanoma.
Keywords: choroid • melanoma • clinical (human) or epidemiologic studies: systems/equipment/techniques