Added Value of Screening Low Dose Computed Tomography of the Chest for the Evaluation of Abdominal Solid Organs by Ultrasound in Physical Check-up Patients

ABSTRACT

PURPOSE: The purpose of this study was to assess the added value of screening low-dose computed tomography of the chest (LDCT) covering the abdomen in evaluating abdominal solid organs to the screening abdominal ultrasonography (US). MATERIALS AND METHODS: We prospectively enrolled a consecutive series of 393 physical check-up patients, who underwent screening abdominal US and LDCT of the chest from January to February, 2008. LDCT covered the lungs, liver, pancreas, gallbladder, spleen, and both kidneys. The 1st screening abdominal US were performed without information from the LDCT, and then abdominal images covered by LDCT were immediately evaluated. Then a 2nd US session was done with additional information from LDCT and US examination was focused to the findings of LDCT. Perpatient and per-lesion analyses were performed. RESULTS: In per-patient analysis, additional focal lesions were found in 20 patients (5.1%) for liver and 9 patients (2.3%) for kidneys in the 2nd US sessions. In per-lesion analysis, 154 and 73 focal lesions were found in liver and kidneys, respectively, in the 1st US sessions. On the 2nd US session, 186 and 86 lesions were found in liver and kidneys, respectively. 20.8% and 17.8% of focal lesions were additionally found on 2nd US session in liver and kidneys, respectively. Most (62.5%) of the additional lesions detected in liver were located in segment 7 and 8, the hepatic dome. CONCLUSION: Previewing LDCT of the chest and abdominal solid organs before performing screening abdominal US can enhance the diagnostic performance of US in physical check-up patients.