Internal Medicine Coding Alert

Let this handy glossary guide you to pain-free documentation.

"It is easy to get lost in the world of migraine-specific terminology," says Chelle Johnson, CPMA, CPC, CPCO, CPPM, CEMC, AAPC Fellow billing/credentialing/auditing/coding coordinator at County of Stanislaus Health Services Agency in Modesto, California.

No wonder. The G43 (Migraine...) section of the ICD-10-CM features 12 different subdivisions to choose from. And the American Migraine Foundation reports that there are about 100 different headache types.

So, here are all the key terms you need to know for pinpointing each condition easily and accurately.

Know these key migraine terms to find correct fourth, fifth, or sixth digit:

Aura: This consists of a series of visual or sensory changes that can include seeing spots, sparkles, or zigzag lines or feelings of numbness or tingling. Sufferers do not always experience aura prior to the onset of a migraine, hence the first two subdivisions of G43: G43.0- (Migraine without aura ...) and G43.1- (Migraine with aura ...).

You may also see the term prodrome in your provider's notes. If you do, you can use the term interchangeably with aura for accurate documentation.

Intractable: Some migraines - and some headaches - never seem to go away no matter how they are treated. Doctors describe these as intractable, a term that Kent Moore, senior strategist for physician payment at the American Academy of Family Physicians, notes is further defined "under the main heading for G43. Here, we read that 'the following terms are to be considered equivalent to intractable: pharmacoresistant [pharmacologically resistant], treatment resistant, refractory [medically], and poorly controlled."

Johnson goes on to point out that the term refractory has a similar meaning. However, intractable migraines are "never-ending, meaning that the patient goes to sleep with the migraine and wakes up with the migraine."

In the ICD-10-CM classification, intractable migraines receive a fifth character, -1, while migraines that are not intractable are documented with -0 as the fifth character. You can see the term in descriptors for several codes, including G43.00- (Migraine without aura, not intractable ...) and G43.11- (Migraine with aura, intractable ...).

Status migrainosus: This term is reserved for an attack that, according to Johnson, "is severe and has lasted, or has been unremitting, for more than 72 hours. This excludes any relief during sleep." Migraines categorized like this are coded with a sixth character, -1, while migraines without it take -9. Examples of codes using these digits include G43.001 (Migraine without aura, not intractable, with status migrainosus) and G43.009 (Migraine without aura, not intractable, without status migrainosus)

Hemiplegic: A somewhat rare condition, G43.4- (Hemiplegic migraine ...) resembles a stroke that lasts for a few hours to several days. The name comes from the terms "hemi," meaning "half," and "plegia," meaning "paralysis."

Persistent vs. chronic: Johnson defines persistent migraines as "ongoing episodes lasting more than one week, with a persisting aura possibly lasting for months. Chronic migraines," on the other hand, consist of "more than 15 episodes per month lasting more than 3 consecutive months." Persistent migraines are classified as G43.5- (Persistent migraine aura without cerebral infarction ...) and G43.6- (Persistent migraine aura with cerebral infarction ...), while chronic migraines are documented with G43.7- (Chronic migraine without aura ...).

Cerebral infarction: Persistent migraines may or may not be accompanied by ischemic strokes. The ones that do not present in this way are categorized under G43.5-. which is reflected in the descriptor, while those that do are categorized under G43.6-. If you document a persistent migraine with cerebral infarction, per ICD-10-CM guidelines, you must also code the type of cerebral infarction using a code from the I63- (Cerebral infarction ...) code set and an additional code from the R29.7- (National Institutes of Health Stroke Scale [NIHSS] score ...) if known.

Put it all together with this scenario

A patient comes to your practice complaining of a headache that has lasted for over three months. The patient also describes experiencing flashing lights and pins and needles. After a comprehensive exam, your physician determines that the migraine had been accompanied by a series of ischemic strokes. The physician also notes that the patient cannot seem to get rid of the migraine despite having taken medication, but that there have been some breaks in the pain during the three-month period. Taking all this into account, you would document G43.619 (Persistent migraine aura with cerebral infarction, intractable, without status migrainosus).

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