Neurosurgery Coding Alert

Anatomical site, laterality, infarctions guide you to correct code.

When ICD-10 hits, you will have to get more specific to report cerebral embolism diagnosis codes. In particular, you'll need to ensure your clinician clearly documents which territory in the central circulation was affected by the embolism. Here's more on what's in store for embolism dx coding.

Look For Embolism Site When There Is No Infarction

In ICD-9, there is only one code that you can report for cerebral embolism without cerebral infarction. You report 434.10 (Cerebral embolism without cerebral infarction) for embolism in all territories of cerebral blood supply.

In ICD-10, your coding options expand to a choice of four codes: I66.09 (Occlusion and stenosis of unspecified middle cerebral artery), I66.19 (Occlusion and stenosis of unspecified anterior cerebral artery), I66.29 (Occlusion and stenosis of unspecified posterior cerebral artery), and I66.9 (Occlusion and stenosis of unspecified cerebral artery) depending upon the specific anatomical location of the embolism. The last code I66.9 applies when either your physician does not mention the site affected by the embolism or the same cannot be construed appropriately in the imaging and other diagnostic studies.

ICD-10 is further specific for laterality. For example, look at the codes below for occlusion or stenosis of the middle cerebral artery.

• I66.01 (Occlusion and stenosis of right middle cerebral artery)
• I66.02 (Occlusion and stenosis of left middle cerebral artery)
• I66.03 (Occlusion and stenosis of bilateral middle cerebral arteries)

The codes are specific for right, left, and bilateral involvement. "This is the true specificity provided by ICD-10 and providers may need guidance in improving their documentation to include these details so they can be accurately reported," says Marvel Hammer, RN, CPC, CCS-P, PCS, ACS-PM, CHCO, owner of MJH Consulting in Denver, Co.

These codes map to ICD-9 codes 434.00 (Cerebral thrombosis without cerebral infarction), 434.10 (Cerebral embolism without cerebral infarction), and 434.90 (Cerebral artery occlusion unspecified without cerebral infarction).

How to select a code: It will be helpful to know the anatomy of cerebral circulation to be able to spot the right code for cerebral embolism in ICD-10. Look at figure 1 to see the cerebral circulation. The three main arteries on both sides, i.e. the anterior, middle, and posterior cerebral arteries, form a circle that gives off numerous other communicating branches to supply the brain.

When reporting a cerebral embolism in any of these major arteries in the cerebral circulation, you will read through the suggestive symptoms that your clinician captures in the clinical notes and then look at the confirmatory imaging studies like CT or MRI he uses to come to a definitive diagnosis.

Learn from These Examples

Since regions in the brain control specific actions, your clinician can narrow down to the diagnosis of cerebral embolism and the potential site of obstruction and you confirm the same as you read the symptoms and signs in the clinical records. The examples below provide cues for selecting the right coding, depending upon how your clinician approached the patient depending upon the presenting symptoms and signs in the patient.

Example 1: If your clinician documents that the patient presented with complaints of repeatedly bumping into objects, hitting obstacles on the roadside, or not being able to see half the printed page when reading, you confirm further down in the clinical notes that the site of occlusion is the posterior cerebral artery and report code I66.29. The symptoms and signs of posterior cerebral artery strokes are numerous and diverse, but may include acute loss of vision, confusion, posterior cranial headache, and dizziness.

Example 2: If your clinician documents that the patient presented with hemiplegia and fixation of the eyes and head turned to the opposite side, he will also investigate to confirm that the patient has had a middle cerebral artery occlusion. You report this condition with ICD-10 code I66.09.

Example 3: If your clinician documents that the patient had conditions like hemiparesis or hemiplegia of the lower limb, apraxia, anosmia, urinary incontinence, or grasp or suckling reflexes, you confirm him suspecting the involvement of the anterior cerebral artery and the reports of imaging and investigations will help him to confirm the diagnosis. In this case, you report ICD-10 code I66.19.