Basics of Coding CT Scans and Ultrasound


Vol. 13 •Issue 14 • Page 9
Coding Corner

Basics of Coding CT Scans and Ultrasound

Computed Tomography

A computed tomography (CT) scan (CPT code range 70450Ð76380) focuses thin beams of ionizing radiation and circles the patient to produce images taken from different angles. This information is fed into a computer that produces two-dimensional images (often termed “slices”) on a monitor. Newer devices acquire information in spiral or helical modes.

CT scans are commonly used to diagnose head injuries, strokes and abdominal problems, as well as to search for the spread of cancer. Although introduced two decades ago, this modality continues to be the mainstay of diagnostic radiology.

Invasive Procedures–Supervision and interpretation (S&I) codes for invasive CT procedures are similar to those for invasive ultrasound procedures in that they now require a corresponding surgical procedure code. These range from 10xxx through 69xxx in the CPT manual. (Note that, in 1992, “complete” procedure codes were deleted from the approved HCPCS list.)

Take the following steps to assign a code for invasive CT procedures.

1. Determine what procedure will be performed and the modality that will be used. Assign the appropriate radiology S&I code.

2. Determine where and how the procedure was performed. Assign the appropriate corresponding surgical code(s).

Needle-Guided Procedures–Three codes are available to describe CT needle-guided procedures, and the chargemaster should include these codes.

75989 Radiological guidance (i.e., fluoroscopy, ultrasound or computed tomography), for percutaneous drainage (e.g., abscess, specimen collection), with placement of catheter, radiological S&I

76360 Computed tomography guidance for needle placement (e.g., biopsy, aspiration, injection, localization device), radiological S&I

76362 Computerized axial tomographic guidance for, and monitoring of, tissue ablation

CT Reconstruction–The CPT manual provides the following specific code for CT reconstruction.

76375 Coronal, sagittal, multiplanar, oblique, 3-dimensional and/or holographic reconstruction of computerized axial tomography, magnetic resonance imaging, or other tomographic modality

This code should be assigned in addition to the initial anatomic site-specific CT procedure code when using computer software to manipulate the original raw data into sagittal, coronal, multiplanar, oblique or 3-D images in addition to the initial, routine transaxial scan.

Ultrasound

This procedure (code range 76506Ð76999) uses special instrumentation to transmit and receive high-frequency sound waves, as sonar does in a submarine. A computer turns the echoes into images that are displayed in real time on a monitor or on permanent film. Ultrasound involves no ionizing radiation, so it has no known risks. The resolution of ultrasound is not as great as one might see with other ionizing modalities. Even so, its use and application are expanding because of significant advances in technology.

Invasive and Needle-Guided Ultrasound–Previously, a radiology S&I code and a complete procedure code were available for needle-guided ultrasound procedures. Like CT, however, the code referring to S&I now requires a corresponding surgical procedure code. (These range from 10xxx through 69xxx in the CPT manual.) This is known as component coding.

To code correctly for invasive procedures, follow these basic steps.

1. Determine the procedure performed and the modality used. Assign the appropriate radiology S&I code.

2. Determine where and how the procedure was performed. Assign the appropriate corresponding surgical code.

3. Use a coding selection such as shown in the following example.

76942 Ultrasonic guidance for needle placement (e.g., biopsy, aspiration, injection, localization device), imaging supervision and interpretation

55700 Biopsy, prostate; needle or punch, single or multiple, any approach

Frequently, hospitals assign only one code (76942) to this procedure. Failure to assign surgical code 55700 to this procedure results in lost reimbursement for the surgical component.

Imaging of Abdomen or Retroperitoneal Areas. Four different codes can be assigned for the diagnostic ultrasound imaging of the abdomen or retroperitoneal areas. The code you select depends on the type of study and the organs imaged.

76700 Ultrasound, abdominal, B-scan and/or real time with image documentation; complete

76705 Ultrasound, abdominal, B-scan and/or real time with image documentation; limited (e.g., single organ, quadrant, follow-up)

76770 Ultrasound, retroperitoneal (e.g., renal, aorta, nodes), B-scan and/or real time with image documentation; complete

76775 Ultrasound, retroperitoneal (e.g., renal, aorta, nodes), B-scan and/or real time with image documentation; limited

Ultrasound exams of the abdomen and pelvic areas may include imaging of both anatomic sites. If ordered, and if full and complete studies are done, it is appropriate to charge for both studies if they are medically necessary.

OB-GYN Multiple Gestation. In CPT 2003, several code definitions were changed, and new codes were added to define both single and multiple gestation and fetus OB studies. The codes are now broken into separate groups referencing “single or first gestation” (CPT 76801, 76805 and 76811) and “each additional gestation” (CPT 76802, 76810 and 76812). These options also refer to studies performed less than 14 weeks, 0 days (76801 and 76802) and greater than 14 weeks, 0 days (76805 and 76810).

Be certain when submitting any of these choices to clearly and completely verify the time frame in which the study was done, as well as whether this is a single or first gestation study as opposed to more than one gestation. Consult the 2003 CPT manual for complete descriptions.

Transvaginal Imaging. When ordered and medically necessary, use a separate code for transvaginal imaging when this mode of imaging is performed in addition to the basic study. CPT 2003 added the following new (and specific) code for transvaginal US of a pregnant uterus.

76817 Ultrasound, pregnant uterus, real time with image documentation, transvaginal

This code may be used with a transabdominal OB ultrasound code when both studies are performed.

Assume the ultrasound department performs a routine pelvic exam. Following a review of the films, the radiologist determines that the exam is technically inadequate for diagnosis. The technologist obtains additional images by the transvaginal method. Use both codes 76830 and 76856.

76830 Ultrasound, transvaginal

76856 Ultrasound, pelvic (nonobstetric), B-scan and/or real time with image documentation; complete

Peggy Hapner is health information management consulting division manager at Medical Learning Inc. (MedLearn®), St. Paul, MN.

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