Radiology Coding Alert

Coding professionals must stay up-to-date on changes in the coding of lung scans and recognize when to use codes assigned to comprehensive procedures like CPT Codes 78588 (pulmonary perfusion imaging, particulate, with ventilation imaging, aerosol, one or multiple projections) as opposed to component codes, which describe only portions of combined procedures. To avoid charges of unbundling, do not use other codes in addition to 78588.

According to Cheryl Schad, BA, CPCM, CPC, owner of Schad Medical Management, a billing and coding consulting firm located in N.J., ventilation studies often are ordered to diagnose conditions like pulmonary embolism and infarction (415.1), bronchopulmonary sequestration (748.5) or pulmonary trauma (861.20). When a patient presents with chest pain, shortness of breath, painful respiration or similar symptoms, the physician will suspect one of these problems, Schad says. A perfusion and/or ventilation scan can help determine precisely whats going on.

A variety of studies may be performed, depending on specific indications, she adds. The radiologist may choose to study perfusion, which relates to the flow of blood to the lungs, or may wish to investigate ventilation, which relates to the flow of air in and out of the lungs. In most instances, various ventilation tests will be combined with a perfusion study.

Single Code to Describe Perfusion Studies Alone

A simple perfusion scan consists of the injection of particles tagged with a radioactive material, which are trapped by the small arterioles of the pulmonary circulatory system, according to Kenneth McKusick, MD, FACR, retired from the Massachusetts General Hospital and currently a member of the American Medical Association CPT advisory committee, representing the Society of Nuclear Medicine. Multiple images then are acquired to assess lung perfusion. This procedure, conducted by itself, would be coded 78580 (pulmonary perfusion imaging, particulate).

Ventilation Studies Coded According to Inhalant

Ventilation studies may be conducted using either radioactive gas or nebulized aerosol agents, says McKusick. Patients inhale one of these substances, and the images are taken to evaluate the ventilation capacity of the lungs.

Two codes are used to describe aerosol ventilation studies, he notes. Codes 78586 (pulmonary ventilation imaging, aerosol; single projection) and 78587 (multiple projections [e.g. anterior, posterior, lateral views]).

Three codes may be assigned to gaseous ventilation studies, McKusick says. They are 78591 (pulmonary ventilation imaging, gaseous, single breath, single projection), 78593 (pulmonary ventilation imaging, gaseous, with rebreathing and washout with or without single breath; single projection) and 78594 (pulmonary ventilation imaging, gaseous, with rebreathing and washout with or without single breath; multiple projections [e.g., anterior, posterior, lateral views]).

Bundled Codes Describe Combined Scans

When the documentation indicates that both perfusion and ventilation scans are conducted in conjunction with one another, there are three codes that may be assigned. The key to determining which bundled code to use is understanding whether the ventilation portion of the study was conducted with an aerosol or gaseous agent, McKusick says.

When perfusion and gaseous ventilation procedures are done, 78584 (pulmonary perfusion imaging, particulate, with ventilation; single breath) or 78585 (rebreathing and washout, with or without single breath) would be assigned.

When the ventilation portion of the combined procedures is performed with a radiolabeled aerosol, 78588 would be assigned (pulmonary perfusion imaging, particulate, with ventilation imaging, aerosol, one or multiple projections).

Because it is the newest of this series of codes, 78588 often presents the most problems to the radiology coder, McKusick says, adding that it was established to eliminate the need for multiple codes when combined perfusion/aerosol ventilation studies are done. In the past, coders would have needed to assign 78580 and 78586 or CPT 78587 to the procedure. Currently, coders who mistakenly report 78588 in addition to any of these other codes are guilty of unbundling.

According to McKusick, this policy follows the precedent set earlier, when 78584 and 78585 were established to cover perfusion/gaseous ventilation combined procedures. This bundled code means radiology coders should never submit claims that combine 78584/78585 with 78580, 78591, 78593 or 78594.

By the same token, he notes, coders should not assign one of these bundled codes (i.e., 78588) with a -52 modifier (reduced services) for any procedure that did not entail both the perfusion and ventilation scans. This approach is unnecessary, since an appropriate code from the respiratory imaging series 78580-78599 may be chosen to accurately describe any of the single procedures.

For example, if a radiologist performs pulmonary ventilation imaging using aerosol and a single projection, 78586 (not 78588-52) should be assigned. Or, if a radiologist performs pulmonary ventilation imaging using a gaseous agent and takes multiple images, the procedure would be assigned 78594 (not 78585-52).

McKusick says coding professionals also should note that code 78588 includes the language single or multiple projections. This means it should be reported only one time for any number of projections that were performed as part of the procedure.