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Published on: August 7, 2019
Impact of Needle Gauge Selection on Sample Adequacy in Ultrasound-Guided Thyroid Fine-Needle Aspiration: A Systematic
Alisa Mohebbi1, Ali Abdi1, Saeed Mohammadzadeh1
1Universal Scientific Education and Research Network (USERN), Tehran, Iran (A.M., A.A., S.M.); School of Medicine, Tehran University of Medical Sciences, Tehran, Iran (A.M., A.A., S.M.).
Purpose:
To compare the impact of the various needle gauges employed in ultrasound-guided fine-needle aspiration (FNA) on the adequacy rate of specimens obtained from thyroid nodules.
Methods:
A systematic review and meta-analysis were performed employing PubMed, Web of Science, Embase, and Cochrane Library databases on December 22, 2024. Studies published post-2010 that compared various needle gauges in thyroid FNA with histopathological confirmation were included. The QUADAS-2 tool was utilized to assess the risk of bias. Data were analyzed using random-effects models in STATA and MedCalc. Heterogeneity was examined through subgroup analyses and meta-regression.
Results:
16 studies involving 3347 patients with 3438 thyroid nodules were included. The meta-analysis indicated no statistically significant difference in adequacy rates between larger and smaller gauge needles (-0.61%, 95% CI: -4.18% to +2.97%, p-value=0.740). Sensitivity analysis and assessment of publication bias revealed strong findings, free from significant outliers or bias. Meta-regression analysis indicated that age, sex, nodule size, and study type did not significantly affect adequacy rates.
Conclusion:
This systematic review with meta-analysis provides compelling evidence that the choice of needle gauge does not significantly influence the adequacy of US-guided FNA for thyroid nodules, suggesting clinicians make informed decisions about needle gauge selection based on factors beyond technical adequacy, such as patient comfort, resource availability, and adherence to regional clinical protocols.

