Intraoperative ultrasonography of the liver in patients with abdominal tumors: a new approach.

Objectives: To compare liver intraoperative ultrasonography (IOU), computed tomography (CT), preoperative ultrasonography (USG), and intraoperative inspection and palpation in the detection of hepatic lesions in patients with abdominal tumors.

Methods: This was a prospective study including 60 patients with abdominal tumors evaluated by USG, CT, inspection and palpation, and hepatic IOU during exploratory laparotomy. Sensitivity, specificity, and positive and negative predictive values for all methods were calculated. Agreement of methods with histopathologic results was calculated by kappa statistics and the Spearman coefficient.

Results: Of the 60 patients, 49 (81.6%) had positive findings for hepatic lesions. Lesions could not be counted in 3 patients. The 46 remaining cases were diagnosed by histologic examination. Sensitivity, specificity, and positive and negative predictive values were 42.9%, 88.9%, 90%, and 40% for USG; 59.5%, 77.8%, 86.2%, and 45.2% for CT; 69.0%, 88.9%, 93.5%, and 55.2% for inspection and palpation; and 90.5%, 77.8%, 90.5%, and 77.8% for IOU, with histologic examination used as a criterion standard. Fair to moderate agreement was found for USG, CT, and inspection and palpation (kappa = 0.24, 0.31, and 0.49, respectively). Substantial agreement was found for IOU (kappa = 0.68). Changes in surgical strategy were made in 19 (41.3%) of the 46 cases with positive findings.

Conclusions: High sensitivity associated with substantial agreement with histopathologic findings shows that IOU is an indispensable evaluation method for hepatic screening in patients with abdominal tumors who undergo laparotomy and should become a routine procedure wherever available.