Abdominal CT findings in patientwith ascites

Abstract EN

Back ground and purposes : Ascites is the collection of free fluid in the peritoneal cavity, normally the peritoneal cavity contain small amount of serous fluid for lubrication (less than 100 ml), free fluid exceeding this amount, considered ascites.

Ascites may result from variety of medical & surgical causes, clinically detectable ascites when its amount exceeding 1500 ml, and when it is clinically important to confirm the presence of suspected ascites, ultrasonography (US) or computed tomography (CT) of abdomen is advisable, and the different CT signs of ascites depend on the amount and distribution of the ascetic fluid.

The Aim : is to study the early and the late signs of ascites on abdominal CT , and to estimate the sensitivity of abdominal CT in diagnosing the cause of ascites Patients and methods : Eighty five patients of mean age 52.2 ± 13.8 years had ascites, diagnosed either clinically or by US (all of them had an US examination), been referred for spiral CT-scan of abdomen as a further diagnostic step to confirm &identify the possible underlying cause of ascites (patients with medical causes of ascites “heart failure, renal failure” had been excluded), abdominal spiral CT scan has been done using 8mm slice thickness (patient took oral diluted gastrografin 1.5-2hrs prior to the examination) & two sets of CT examinations had been done (without I.V & with I.V omnipaque “350mg / ml.

Results : This study showed that CT was as sensitive as US in detection of ascites , and the different signs of ascites on CT images depended on the amount of ascetic fluid producing either (early) or (late) signs, the late signs were more frequently seen in this study.

This study also showed that CT was more useful in identifying the underlying cause of ascites (especially when related to the peritoneum, momentum or to the bowel) and the extent of the pathology and its proper staging.

The frequency of the underlying causes of ascites were as follows : 62 % due to underlying neoplasm, 15.5 % due to underlying liver cirrhosis, 8.6 % due to underlying inflammatory conditions & 3.4 % were post traumatic, however, there were 10.3 % of cases for which the CT scan didn’t give us an idea about the underlying cause.

Conclusion : CT was as sensitive as US in detection of ascites, and more useful in identifying the underlying cause of it, but still about 10 % of patients requires further investigative steps.