Abstract

To compare cytological betvveen 21 G and 22 G injector needles in the US-guided fine-needle aspiration biopsy (FNAB) met-hod of thyroid gland nodules forms the basis of our study. We statistically evaluated cytological results of 102 FNAB performed vvith 21 G (green) needles betvveen 2005 September-2006 January (Group 1) and 136 FNAB vvith 22 G (black) needles betvveen 2006 February-2006 May (Group 2). The rates of maügnant (positive)/berıign (negative) were not different between Group 1 and Group 2 (p= 0.292). Age, gender, performers of FNAB, injectors used, size and features of nodules were similarat eithergroup (p> 0.05). The patients whose biopsy results were blood elements and non-diagnostic and who were found false positive or faise negative at follow-up were accepted unsuccess-ful, whereas the patients who were true positive or true negative were successful. Analysis was performed in both conditions where the patients diagnosed as suspected maiignant were included/excluded. Success was compared betvveen both needle groups. The mean age of the patients and male/women ratio were 47.5 ± 12.3 years (46.8 ± 12.5 in Group 1, 48.0 ± 12.2 in Group 2) and 30.8% (37.8% in Group 1, 25.9% in Group 2) respectiveiy. 15.1% (13 cases) of Group 1 was unsuccessful and 84.9% (73 cases) successful; whereas 8.3%> (10 cases) of Group 2 was unsuccessful and 91.7% (110 cases) successful. Although Group 2 was more successful; the statistical difference was not significant betvveen 2 groups (p= 0.127). The result was the same in including of suspected maiignant cases (p=0.102). İn total 238 cases, 87.4% in accuracy, 100% in positive predictive value, and 85.0% in negative predictive value were found. No complication was observed in either group. Success rate percent, despite not significant statistical difference, in the cases of thyroid FNAB vvith 22 G needles (black) was higher than that vvith 21 G needles (green). To compare 21 G or 22 G needles vvith the thinner needles can make significant increase in the success rate statistically.