Diagnostic Efficacy of Single-Pass Abdominal Multidetector-Row CT: Prospective Evaluation of a Low Dose Protocol.

OBJECTIVES: To evaluate the diagnostic efficacy of single-pass contrast-enhanced multi-detector CT (CE-MDCT) performed with a low radiation-high contrast (LR-HC) dose protocol in selected patients with non traumatic acute bowel disease. METHODS: Sixty-five (32 M; 33 F; aged 20-67 years) consecutive patients with non traumatic acute bowel disease underwent single-pass CE-MDCT performed 70-100 sec after i.v. bolus injection of a non ionic iodinated contrast media (370 mgI/ml). In forty-six patients (70%) up to 1.2-1.4 L of a 7% PEG solution was orally administered 45-60’ prior to the CT examination. Patients were then divided in two groups according to the age: A (20-44 years; n= 34); B (45-70 years; n=31). Noise Index (NI) and contrast medium dose were selected as follows: A (NI=15; 2,5 ml/kg); B (NI =12,5; 2ml/kg). All patients of group A underwent thyroid functional tests at 4-6 wks. Final diagnoses were obtained by open (n=12) or laparoscopic surgery (n=4), endoscopy w/out biopsy (n=24), clinical (n=19) and/or instrumental (US) (n=6) follow-up at 11 + 4 months (range 6-18 mo.). Statistical analysis was performed by Chi-Square and Student's t-Test for categorical and continuous variables, respectively. RESULTS: Sensitivity and specificity were 91.3 vs 95.4% (p = 0.905) and 90.9 vs 88.8% (p = 0.998) with an overall diagnostic accuracy of 91.1 vs 93.5% (p = 0.756) whereas the radiation (mSv) and contrast media dose (ml) were 7.5 ± 2.8 and 155 ± 30 for Group A and 14.1 ± 5.3 and 130 ±24 for Group B (p < 0.001), respectively. No patients of group A showed laboratory signs of thyreotoxicosis at follow-up. CONCLUSIONS: The LR-HC has proved to be a safe and a dose-effective protocol in the evaluation of selected young patients with non traumatic acute bowel disease.