Comparison of power Doppler and thermography for the selection of thyroid nodules in which fine-needle aspiration biopsy is indicated

Radiol Bras. 2016 Sep-Oct;49(5):311-315. doi: 10.1590/0100-3984.2014.0111.

Abstract

Objective: To compare two methods-power Doppler and thermography-for the analysis of nodule vascularization and subsequent selection of nodules to be biopsied.

Materials and methods: A total of 510 subjects with thyroid nodules were analyzed by power Doppler and submitted to fine-needle aspiration biopsy (FNAB). Thirty-seven patients were submitted to nodule excision (29 due to carcinoma or suspected carcinoma and 8 by patient choice). Among those patients, power Doppler had raised the suspicion of malignancy in 39 lesions, compared with 48 for FNAB. Another group, comprising 110 patients, underwent thermography, which raised the suspicion of malignancy in 124 thyroid nodules, as did FNAB. Malignant nodules were excised in all 110 of those patients (95 underwent nodulectomy and 15 underwent thyroidectomy), malignancy being confirmed by intraoperative examination of frozen biopsy samples.

Results: In relation to the FNAB findings, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of power Doppler were 95.16%, 23.52%, 96.22%, 16.70%, and 89.51%, respectively, compared with 100%, 58.06%, 87.73%, 100%, and 89.51%, respectively, for thermography.

Conclusion: Thermography was more precise than was power Doppler for the selection of thyroid nodules to be biopsied.

Objetivo: Comparar dois métodos de análise de vascularização de nódulos - power Doppler e termografia - na seleção para submissão a biópsia.

Materiais e métodos: Foram analisados 510 pacientes portadores de nódulos tireoidianos pelo power Doppler, todos submetidos a punção aspirativa por agulha fina (PAAF). Desses pacientes, 37 tiveram seus nódulos ressecados (29 por carcinoma ou suspeito para carcinoma e 8 por decisão pessoal), totalizando 39 lesões suspeitas para malignidade ao power Doppler e 48 à PAAF. Em outros 110 pacientes foram detectados, pela termografia e PAAF, 124 nódulos tireoidianos, que foram submetidos a excisão (95 casos por nodulectomia e 15 casos por tireoidectomia total) e tiveram malignidade confirmada no exame de congelação intraoperatório.

Resultados: O power Doppler e a termografia apresentaram, respectivamente, sensibilidades de 95,16% e 100%, especificidades de 23,52% e 58,06%, valores preditivos positivos de 96,22% e 87,73%, valores preditivos negativos de 16,70% e 100% e acurácias de 91,83% e 89,51%, quando comparados com a PAAF.

Conclusão: A termografia foi mais precisa que o power Doppler na seleção de nódulos tireoidianos com indicação de biópsia.

Keywords: Thermography; Thyroid gland; Thyroid nodule/blood supply; Ultrasonography, Doppler.