Radiology Coding Alert

Correct use of diagnosis codes is crucial to any radiology practices reimbursement. According to Medicare, countless claims each year are rejected as unprocessable for two specific reasons:

Coders do not code to the highest order of specificity; or

Coders do not assign the fourth or fifth digits accurately.

Medicare has long made it clear that truncated ICD-9 Codes codes reported with too few digits will be rejected. Nonetheless, many coders are still not coding to the highest order of specificity, says Susan Garrison, CPC, CPC-H, MPC, CPAR, MCS, president of the American Academy of Professional Coders (AAPC) national advisory board and a senior manager with 3M HIS Consulting Services, which provides coding, reimbursement and management support to physicians and practices in the Atlanta area.

In addition, coders often fail to follow the ICD-9 basic coding guidelines for outpatient and physician services, which state that professionals should code to the highest degree of certainty for each encounter. Some coders make the mistake of assuming that this means every diagnostic code should have five digits, points out Garnet Dunston, CPC, MPC, president and CEO of the coding services firm Dunston Enterprises Inc. in Phoenix, and past secretary for the AAPC national advisory board. They will add a decimal point to a three-digit code and then attach one or two zeroes. This is just as inaccurate as truncating a code that does require more digits.

Either error will cost a radiology practice time and money, Dunston says. Medicare and many other third-party payers consider incomplete or inaccurate codes invalid. This nearly always will result in additional denials, correspondence and payment delays.

To minimize errors made in diagnostic coding, experts offer the following three tips.

1. Understand the reasoning behind the ICD-9 coding system. ICD-9 contains codes with three, four or five digits. Most three-digit codes serve as headings for broad categories, which then need to be further divided. The fourth and fifth digits which follow a decimal point added to the core three-digit code were established to provide more detail about the nature of the disease or condition for which the patient is being seen. Typically, codes with a fourth digit are called subcategory codes, while those with a fifth digit are referred to as subclassifications.

Example of codes that require a fourth digit: The three-digit ICD-9 code 162 (malignant neoplasm of trachea, bronchus, and lung) always requires the decimal point and a fourth digit. The fourth digit identifies the subcategory of the malignancy 162.0, for example, identifies the malignancy as occurring on the trachea, while 162.2 localizes it to the main bronchus.

Dunston points out that coders must recognize that a zero following the decimal point does not indicate that the fourth digit isnt really necessary. This is not like what we learned in math class, where the zero after the decimal represents no value, she says. ICD-9 uses the zero in this position to provide very specific and necessary information.

Example of codes that require a fifth digit: A code that always requires a fifth digit is chest pain (786.5). It is already a four-digit code, describing a subcategory of 786 (symptoms involving respiratory system and other chest symptoms), but requires further classification. Code 786.52 indicates painful respiration, for instance.

2. Recognize that three-digit codes are rare. If radiology coders find themselves assigning three-digit codes frequently, they need to review their ICD-9 coding book, Dunston says. There are truly very few three-digit codes that may be used legitimately. If a coder is assigning three-digit codes, thinking this is correct, it is time for a refresher course in diagnosis coding. It just wont happen very often.

As a matter of fact, there are about 13,000 ICD-9 codes and of these, only about 100 appear as three-digit codes that do not need additional digits. Among those that radiology coders (especially those who code for interventionalists) may encounter are 430 (subarachnoid hemorrhage) and 431 (intracerebral hemorrhage).

By the same token, Dunston warns, if coders have a legitimate reason to report a three-digit code, they should not shy away from it. Because it is rare, some coders may worry about assigning one of these codes. In fact, they may add a decimal and attach one or two zeros just to be safe. But adding unnecessary digits is just as great an error as reporting too few. Both will result in denials.

Editors note: Because many radiological procedures can be categorized as diagnostic, coders often find themselves coding signs and symptoms rather than definitive diagnoses. Signs and symptom codes serve as provisional diagnoses and nearly always require a fifth digit.

3. Beware of dump codes. In their zeal to code to the highest level of specificity, some radiology coders assign what is commonly referred to as a dump code unspecified codes that appear in the ICD-9 manual. These catch-all codes are frowned upon by Medicare and other payers because they are nonspecific or ill defined, Garrison says. Coders should use them only after carefully checking all other options.

Prime examples of dump codes fall under chest pain (786.5x), which requires a fifth digit. Inappropriately adding a fifth digit of 0 or 9 creates two dump codes 786.50 (chest pain, unspecified) and 786.59 (chest pain, other).

If you are aware that you are about to assign a code like this a code that could be considered a dump code go back to the medical record, advises Garrison. Look for definitive information that will help you pinpoint the correct diagnosis code. If you cant find the information in the record, ask the physician to clarify. But dont go too far to create a code that is not truly documented in the chart.

Use Reference Manuals and Update Tools

Fortunately, there are manuals and tools available that radiology coders can rely upon to ensure their diagnosis coding is accurate. Its important for coders to have an ICD-9 coding manual at their fingertips, says Dunston. And it needs to be current. There are radiology practices that believe that it is not necessary to buy a new manual every year. But, its necessary to do so because diagnosis codes change frequently new codes are added, and old codes may be deleted or revised.

Editors note: See this months insert for a list of the ICD-9 codes that will be added or revised for 2001. These codes will become official on Oct. 1, 2000, and will become effective for Medicare on Jan. 1, 2001. Other payers also may implement them at that point, or shortly thereafter. Check with your local carriers to determine their timeframe.

Of course, just having a current manual on your bookshelf isnt enough, she emphasizes. You must learn how to use it and refer to it regularly. Many coding professionals recommend manuals that are color-coded and use clearly defined symbols to indicate codes requiring fourth and/or fifth digits.

In addition, Garrison adds, coders should always use the index and the tabular sections of their ICD-9 manual. Its important to confirm codes you locate in the index by looking them up in the tabular pages, she says, because some indexes do not contain fifth-digit designations. Dont depend on the index to select your code youre inviting trouble.

Dunston also notes that coders need to read the tabular sections carefully. Your coding book may have the appropriate symbols to indicate additional digits, but they may be easy to overlook. Depending on the length of the category you are reviewing, the subclassification may be listed on two or more pages after the beginning of the listing.

Besides using the ICD-9 manual correctly, coding professionals recommend that radiology practices review their encounter forms or superbills. These tools often list only three-digit categories rather than all the possible subcategories and subclassification codes. Radiologists inadvertently may truncate diagnosis codes because they are relying upon these forms. If coders automatically transfer the incorrect three-digit code to the claim form, the claim may be rejected automatically.

Coders should be aware that this may happen and not rely only on the encounter form, Dunston says. Plus, coders should highlight catch-all codes on their encounter forms and be wary of using them too frequently.