RESIDUAL CAVITIES AFTER SURGERY FOR HEPATIC HYDATID CYSTS AN ULTRASONOGRAPHIC EVALUATION

Ultrasonography has made it easier to diagnose precisely hepatic hydat id cysts, but the interpretation of images of residual cavities persis ting long after operation can be difficult. We reviewed the clinical h istories of 22 children treated surgically for hepatic hydatid cysts a t our hospital (1985-1992) to find clues to the proper attitude toward residual cavities. The children's mean age was 7.4 +/- 2.5 years. Fou rteen children had single cysts (11 right and 3 left) and 8 children h ad multiple cysts, one of them 30 cysts (16 right and 14 left). The me an ultrasonographic diameter of the 44 cysts was 6.1 +/- 3 cm. Cystect omy with partial pericystectomy was performed in every case. Six month s after operation, 29 cavities had disappeared, became calcified, or w ere substituted with fibrous scar tissue. The remaining 15 residual ca vities had a mean diameter of 3 +/- 1 cm. The residual cavities exhibi ted little change at 12 months (2.8 +/- 1 cm), but at 18 months 9 had disappeared, 2 that increased in size turned out to be 2 new cysts tha t developed near the original lesion, and 4 remained the same size. Of these 4 stable lesions, surgery performed in 2 found no cysts and 2 h ave been followed-up ultrasonographically for 5 years. This short seri es shows that ultrasonography is useful in the diagnosis and follow-up of residual cavities after surgery for hepatic hydatid cysts. Most re sidual cavities disappeared by 18 months. In the cavities that persist ed, our findings suggest that surgical treatment is justified only whe n the cyst becomes larger on ultrasonography.