Evaluation of Usability and Efficacy of Strain Elastography Method Concurrently with Preoperative Ultrasonography in Cases of Hydatid Cyst.

Background: Hydatid cysts (HCs), which are among the cystic lesions of the liver, are frequently encountered in endemic areas. Routine imaging modalities are sometimes insufficient to differentiate HC types, and ultrasound (US) elastography has just begun to be used for this purpose. In this study, the effectiveness of the strain elastography (SE) method in preoperative HC cases was investigated, and the relationship between HC types and elastography values was evaluated.

Methods: HC cases that underwent SE simultaneously with preoperative US between January 2019 and February 2021 were evaluated retrospectively, and 75 cases were included in the study. In addition to elastography data, cyst typing according to the World Health Organization (WHO) classification was also available.

Results: Thirty cases were male and 45 cases were female, the median age was 48 years, and the interquartile range was 41 years. According to the WHO classification, 15 cases were Type I, 27 cases were Type II, and 33 cases were Type III HC. Median strain ratio (SR) values were 5.69 (4.07-14.47) for Type I, median 1.49 (1.26-1.74) for Type II, and median 0.21 (0.13-0.30) for Type III, and there was a highly significant relationship between HC types and SR values ( < 0.001). There was also a very strong (-) directional correlation between HC type and strain rate ( < 0.001, Spemann rho (ρ): -0.928).

Conclusion: US elastography is a new modality in the diagnosis of HC types, and there are few studies available. In this study, unlike the literature, it is the first time that HC typing and discrimination have been used using the SE technique, which is remarkable.