Computerized Tomography (CT) imaging, also known as CAT scanning (Computed Axial Tomography) provides images of a combination of soft tissues, bones and blood vessels. The CT scan is based on the x-ray principal. As x-rays pass through the body, they are absorbed at differing levels, creating a profile of x-ray beams that is registered on film.

In the absence of signs or symptoms of a disease or condition, or in the absence of conventional diagnostic studies (i.e., standard x-ray and/or ultrasound), a CT scan will not be considered medically necessary.

The following guidelines apply when multiple CT scans are performed on the same day:

• A separate payment may be made for a CT scan of the orbits, the sella turcica, the outer, middle, or inner ear, or the maxillofacial area in addition to a CT scan of the head/brain.
• A separate allowance should not be made for CT of the posterior fossa when performed with a CT scan of the head/brain. Itemized charges should be combined under code 70450, 70460, or 70470 as appropriate.
• A separate payment may be made for CT of the pelvic region in addition to CT of the abdomen. CT scan of the pelvis includes payment for studies of the male or female internal reproductive organs.
• CT scan of the abdomen/retroperitoneum includes payment for studies of the kidney, adrenals, liver, and pancreas.

When an enhanced study is performed on the same day as an unenhanced study of the same organ,  the appropriate combination code should be used.

When both MRI and a computed tomography CT scan are performed on the same day for the same anatomic area, payment should be made for the CT scan. The MRI may only be paid if supporting documentation is submitted to establish medical necessity for both studies.

Xenon Cerebral Blood Flow CT Study (76497)
When a Xenon cerebral blood flow CT study is reported on the same day as a conventional CT study of the head or brain (codes 70450-70470), payment may be made for the conventional CT study. However, the Xenon study is not generally accepted by the medical community as clinically useful in diagnosing or treatment. When reported, it is denied as not medically necessary. A participating, preferred, or network provider cannot bill the member for the denied service.

For information on CT angiography (CTA) for coronary artery evaluation see Medical Policy Bulletin X-54.

NOTE:

This policy is designed to address medical guidelines that are appropriate for the majority of individuals with a particular disease, illness, or condition. Each person's unique clinical circumstances may warrant individual consideration, based on review of applicable medical records.

This medical policy may not apply to FEP. Medical policy is not an authorization, certification, explanation of benefits, or a contract. Benefits are determined by the Federal Employee Program.