Evaluation of the Effect of Patient Preparation Using Castor Oil on ADC Value of Focal Liver Lesion

PURPOSE: To estimate the role of patient preparation using castor oil on the ADC value of focal liver lesion. PATIENTS AND METHODS: Retrospective case-control study over more than two years. Magnetic resonance imaging (MRI) scan, including diffusion-weighted imaging (DWI) of the upper abdomen performed for 87 cases and 71 controls in patients with focal hepatic hemangiomas. Cases were prepared using castor oil prior to the scan without identifiable unwanted effect, while controls did not receive any special preparation. Since liver hemangioma is a common lesion, it was selected and used as a sample. Apparent Diffusion Coefficient (ADC) values of focal liver lesion were calculated in cases and controls. RESULTS: The mean ADC value of liver hemangioma was lower in cases compared to controls; the mean ADC value was (2.21±0.39x10ˉ(3)mm(2)/s) in cases and (2.51±0.49x10ˉ(3)mm(2)/s) in controls. Left lobes were more affected by lesions; the mean ADC value of the left lobe lesions was (2.26±0.37 x10ˉ(3)mm(2)/s) and (2.86±0.43 x10ˉ(3)mm(2)/s) in cases and controls, respectively. The ADC value of lesions in the right lobe was (2.19±0.39x10ˉ(3)mm(2)/s) in cases and (2.39± 0.45x10ˉ(3)mm(2)/s) in controls. There was a significant segmental ADC variation; lesions at segments II, III, IVb, and V demonstrated illusive ADC elevation in controls. CONCLUSION: There is erroneous elevation of lobar and segmental ADC value of liver hemangiomas in non prepared patients. This Potential source of error (peristalsis, partial volume, and paramagnetic gas effect of gastrointestinal tract) on hepatic lesions’ ADC value can be avoided by proper preparation using castor oil prior to MRI scanning.