Can Ultrasound Replace Computed Tomography (CT) Scan in Those Unable to Have Computed Tomography (CT) Contrast Agents
Can Ultrasound Replace Computed Tomography (CT) Scan in Those Unable to Have Computed Tomography (CT) Contrast Agents
Computed tomography (CT) scan, performed with contrast enhancement, is one of the most
 commonly requested examinations in diagnostic imaging. In a patient with an elevated
 creatinine or an allergy to contrast agents, the scan may be performed without the benefit of
 contrast enhancement. Ultrasound (US), performed with contrast agent enhancement does not
 have any nephrotoxicity and may be performed on patients with CT contrast allergy. The
 investigators propose that US with Contrast enhanced ultrasound (CEUS) is superior to
 unenhanced CT scan in this population.
Contrast enhanced computed tomography (CT) is one of the most common investigations performed
 in any radiology department, used widely in evaluating pathology in any part of the body.

 Historically, it is well known that the use of contrast agents for CT scans may result in
 nephropathy, or renal failure. Nephrotoxicity associated with the injection of CT contrast
 agents may occasionally occur in healthy individuals and more commonly in those with
 borderline renal function. If abnormal kidney function is known to exist in a patient sent
 for CT scan, the examination is performed without the valuable assistance of contrast
 enhancement. Further, if prior hypersensitivity to the contrast agent for CT scan is known,
 again, the scan will be performed without the use of contrast agent.

 Ultrasound (US) performed conventionally in grayscale and with Doppler is able to evaluate
 most abdominal and pelvic organs and also provides vascular information related to large
 vessel blood flow. Contrast enhanced ultrasound (CEUS) provides more precise information on
 blood flow than is available with Doppler and has been shown to be comparable to CT scan in
 some circumstances. We believe that a comparison of conventional US, with CEUS, and
 unenhanced CT scan would clearly favor ultrasound for detection of soft tissue pathology on
 the basis of its inherent tissue contrast differentiation.
Inclusion Criteria:

 -  unenhanced CT scan of abdomen

 -  known renal compromise

 -  known hypersensitivity to CT contrast agents

 Exclusion Criteria:

 -  CT scan performed with contrast agent