Radiology Coding Alert

Focus on date of service, not date of interpretation, when making modifier determinations.

With the sheer volume of charts radiology coders handle on a regular basis, it's inevitable that you will be forced to utilize nearly every applicable modifier under the sun at one point or another. While some modifiers don't require much time or effort on the coder's part, the same can't be said for other, less frequently used modifiers.

"On the surface, modifiers 76 (Repeat Procedure or service by Same Physician or other qualified health care professional) and 77 (Repeat Procedure by Another Physician or other qualified health care professional) seem simple enough," explains Lindsay Della Vella, COC, medical coding auditor at Precision Healthcare Management in Media, Pennsylvania. "But, there's a few important elements coders need to take into account to correctly implement these modifiers in their respective scenarios - with arguably the most important factor of the bunch being time," Della Vella says.

Check out these two real-life examples where time - specifically date of service - is crucial in deciding whether modifiers 76 and 77 are appropriate.

Know the Difference Between Date of Service and Time of Interpretation

Example 1: A primary care physician refers a patient with a chronic headache for a computed tomography (CT) scan of the head without contrast. Dr. X performs the CT scan at 2:30 PM and interprets it 4:45 PM. After a syncopal episode, the patient returns that same night to have another CT head without contrast performed at 11:45 PM. Dr. Y interprets the report at 12:15 AM the following day.

First, you will want to decide on the correct CPT^® and diagnosis codes. For the CT scan of the head without contrast, you will apply code 70450 (Computed tomography, head or brain; without contrast material). Unless the impression reveals a definitive cause for the headache, you should refer back to the indication for the primary diagnosis. The diagnosis of "chronic headache" is coded as R51 (Headache). Make sure not to mistake a headache of any chronicity as a migraine. Unless the physician documents the term "migraine," you should not make any assumptions.

As for the second CT scan, you will have to take additional elements into consideration. Since the scan is a duplicate of the previous CT scan of the head without contrast, the CPT^® code remains the same. Beginning coders may learn the hard way that unless you apply a duplicate procedure modifier for the second CT scan, the payer will ultimately deny it as a duplicate.

Before making a determination on modifier, you will want to take a look at two factors. First, you want to check the interpreting physician to determine whether it was Dr. X or Dr. Y who interpreted the scan. Second, you will want to check the time the procedure was performed. Since the procedure was performed by a different physician before midnight on the same day, you will want to apply a modifier 77 to the second 70450. You will apply the diagnosis code R55 (Syncope and collapse) for the syncopal episode. You should not include the patient's prior diagnosis of a headache unless it is documented as an indicating diagnosis alongside "syncopal episode." Rather, you should treat the report as a separate entity when determining the correct diagnosis code.

Careful: Some coders might make the mistake of using the time the physician interprets the report to determine whether a duplicate modifier is necessary. However, you should always rely on the time the procedure was performed, not the time the radiologist dictated the report, when making a modifier determination. This also applies to date of service (DOS). The date of service is just that - the date and time the service was performed, not read. So, if an exam begins at 11:59 PM on Monday and concludes at 12:15 AM the following day, you will still want to make sure the date of service is Monday.

Consider both Interpreting Provider and Date of Service

Example 2: A patient is scheduled for a magnetic resonance imaging (MRI) scan of the brain without contrast due to symptoms of a possible recent stroke. The MRI is performed by Dr. X at 4:45 PM. Later that night, the patient is ambulated to the hospital after falling and hitting their head. At 11:45 PM the patient receives a complete skull X-ray. At 12:02 AM the patient receives an MRI scan of the brain with and without contrast. Dr. X interprets both exams at 12:15 AM.

Immediately, you should take note that there is only one interpreting provider for all three examinations. Therefore, modifier 76 is the only duplicate modifier you should keep in consideration. For the first MRI, you should apply 70551 (Magnetic resonance [eg, proton] imaging, brain [including brain stem]; without contrast material) without modifier 76 since it's the first exam. Next, you will code the skull X-ray the same regardless of time since it was only performed once. For the complete skull X-ray, you will apply code 70260 (Radiologic examination, skull; complete, minimum of 4 views). Since the exams are imaging the same anatomical site, you can check the Correct Coding Initiative (CCI) edits between the two codes to find you do not need an overriding modifier.

Additionally, since the MRI of the brain with and without contrast is performed the following day, you do not need to consider modifier 76 in this instance. You will submit the procedure using code 70553 (... without contrast material, followed by contrast material(s) and further sequences).