Objectives: The main purpose of the present study was to determine the efficacy of real-time elastography (RTE) and strain elastog- raphy (STE) in the diagnosis of different thyroid diseases. We also aimed to calculate the cut-off points for the differential diagnosis of subacute thyroiditis (SAT), Graves’ disease (GD), and Hashimoto’s thyroiditis (HT), which have a similar B-mode sonographic ap- pearance.

Patients and Methods: A total of 24 patients with GD (10.9%), 94 patients with HT (42.7%), 20 patients with SAT (9.1%), and 82 indi- viduals with normal healthy thyroids (37.3%) were included. Grayscale ultrasound evaluation of thyroid glands was performed with standard transverse and longitudinal planes before sonoelastography.

Results: The strain ratios (SRs) (mean ± standard deviation) of patients with GD, HT, and SAT, and the control group (CG) were 14.7 ± 14.8, 8.4 ± 9.6, 23.2 ± 10.8, and 1.37 ± 0.8, respectively. The cut-off points of strain elastography of the patients with GD, HT, and SAT to the CG were 2.69 (sensitivity 92%, specificity 90%, area under the curve (AUC) 0.983; 95% CI), 2.18 (sensitivity 100%, specificity 85%, AUC 0.898), and 5.54 (sensitivity 100%, specificity 100%, AUC 1.000; 95% CI), respectively. The cut-off point of the strain ratios (SR) of the total amount of patients with HT and GD to SAT was 14.79 (sensitivity 80%, specificity 85%, AUC 0.869; 95% CI).

Conclusion: Statistically significant differences were noted in the SR values and elasticity scores of the three experimental groups, and the CG. The elasticity scores of the SAT and HT groups were not significantly different from those of the GD group. The diag- nostic performance of strain ratio elastography (P < 0.0001) was higher than that of real time elastography (P < 0.001). In terms of differentiating diagnosis, ES could differentiate SAT from HT, but it had no value in differentiating GD from HT and SAT. We also found statistically significant SRs for the differential diagnosis of SAT from GD and HT. Strain elastography could be a useful method for the differential diagnosis of SAT from a healthy population or from other types of thyroiditis such as GD and HT.

Keywords: Sonoelastography, Strain Elastography, Real-Time Elastography, Subacute Thyroiditis, Hashimoto’s Thyroiditis, Graves’ Disease

해당 논문은 elastography에서 strain ratio값이 그레이브병 환자에서 다른 갑상선염 환자들과 확연히 다른 차이를 보였다는 걸 보고한 문헌입니다. 물론 종합병원급에서 strain elastography를 운용하는건 어렵겠지만, real-time elastography 기능이 있는 초음파장비를 운용하고 있다면 갑상선기능항진증 환자에서 조직검사를 시행하기 전에 임상병리수치만으로 구별이 어려운 상황에서 영상의학과의사가 도움을 줄 수 있음을 시사하고 있습니다.

최근에 제가 같은 생각을 해오다 혹시 elastography로 이런 감별이 가능한지 문헌을 찾고 있었는데, 바로 나오더군요. elastography가 점점 더 많은 임상영역에서 활용되가는 추세를 느낄 수 있었습니다.