Preauthorize CT exams of abdomen and pelvis separately

As part of Blue Cross Blue Shield of Michigan’s PPO Radiology Management Program, participating providers must contact AIM Specialty Health^® for prior authorization of non-emergency, outpatient imaging procedures.

Recently, Blue Cross has become aware of facilities performing both a CT of the abdomen and a CT of the pelvis when only one of these exams has been deemed medically necessary by AIM. It’s important to note that these exams are separate and distinct, and represented by different CPT codes. If a concurrent performance of these exams requires clinical review for the combination code, the ordering physician or provider must have the exam reviewed for medical necessity. From a clinical perspective, the two exams can be differentiated as follows:

• CT imaging of the abdomen covers sections obtained from the diaphragmatic dome through the iliac crests. This anatomy includes the liver, biliary tract, pancreas, spleen, ad renal glands, kidneys, proximal ureters, lymph nodes, stomach and portions of the intestinal tract.
• CT imaging of the pelvis extends from the iliac crests through the pubic symphysis and incudes the distal ureters, urinary bladder, lymph nodes, portions of the intestinal tract, as well as the prostate gland and seminal vesicles in males and the uterus, tubal structures and ovaries in females.

In many cases, concurrent or combined CT imaging of both anatomic areas aren’t required. For example, further characterization of one or more space-occupying liver lesions with triple-phase CT imaging doesn’t require a pelvic CT. Short term follow-up of an abnormality located in either the abdomen or pelvis doesn’t need imaging of the other anatomic region. In these cases, repeat combined imaging of both areas subject the patient to unnecessary radiation and is considered an ineffective use of medical resources.

There are several clinical reasons to perform combined abdominal and pelvic CT imaging. For example, evaluation of obstructive uropathy or work-up of acute intestinal tract abnormalities, such as suspected appendicitis or diverticulitis, may require imaging of both areas. AIM's clinical guidelines list further indications for combined imaging under the section titled “CT of the Abdomen & Pelvis." In these cases, the ordering provider should request clinical appropriateness reviews for both exams.

If it’s discovered that a concurrent and combined CT is medically necessary after the initial request for one of the separate abdomen or pelvis CT modality was already approved through AIM, you should  contact AIM to void the original request and request a medically necessity review through AIM’s provider portal before  the retro review period expires.

The computed tomography angiography, or CTA, also has an individual and concurrent modality. The CTA abdomen and pelvis are distinct from each other and have different medical necessity criteria. If a concurrent CTA is required, the actual combined procedure code should be requested for medical necessity review.

Health care providers providing the imaging should validate the exams included in the clinical review from the ordering provider before rendering the service, either by calling AIM at 1-800-728-8008 or accessing information online through AIM's provider portal at AIMSpecialtyHealth.com.