<prompt> Which of the following is the most sensitive imaging modality for the diagnosis of ureteric stones in a patient with acute colic?X-ray KUB regionAbdominal ultrasoundNon contrast CT scan of the abdomenContrast enhanced CT scan of the abdomen  <response>: The most sensitive imaging modality for diagnosis of ureteric stones in a patient with acute colic is non contrast CT scan of abdomen. It has a sensitivity and specificity greater than 90. Advantages of using it are: It avoids problems due to intravenous contrasts, allows diagnosis of non urological pathology. Disadvantage: It is associated with significant exposure to ionizing radiation 2.5cGy. Ref: Emergency Surgery By Adam Brooks, Page 127; SRBs Manual of Surgery By Sriram Bhat, 3rd Edition, Page 959 