The Avaibility of Strain Elastography in a Hydatid Cyst – Interobserver Study

BACKGROUND To differentiate the hydatid cyst (HC) types by ultrasound elastography using two different sizes (4 mm and 8 mm) of the region of interest (ROI) and asking two different radiologists (interobserver) for their opinion. MATERIAL/METHODS Patients with HC were evaluated by USG elastography. The statistical anayses were performed using Strain index (SI) which is the unit of strain elastography. RESULTS A total of 26 out of 33 patients were female, and 7 were male. The mean age was 38.85±17.62 (range from 10 to 72 years). Type I: 6, Type 2: 6, Type III: 6, Type IV: 11, Type V: 4. There was no significant difference in HC SI (regardless of types) between O1 and O2, and 4-mm and 8-mm ROI (p>0.05). There was no statistically significant difference between SI of HC types of interobservers (O1-O2) and ROI sizes (4-8 mm) (p>0.05 for all parameters). The highest correlation between HC types and ROI sizes was in ROI size of 4 mm. CONCLUSIONS The correlation between SI and types was reliable in standard-applied 4-mm ROI. There was no statistically significant difference between interobservers in SI values. Thus, elastography tecnhnique is objective for HC but not appropriate to differentiate the types.