Radiology Coding Alert

Know what symptoms are associated with each type of embolism.

Sometimes, learning the nuances of a condition can be useful in determining the correct diagnosis code. You may feel comfortable coding cerebral embolisms without understanding some of the inherent mechanisms at play, but as you’ll see, that might limit your capacity to be the best coder you can be.

Where cerebral embolism coding can be tricky is discerning between the symptoms and conditions that are associated with the embolism and those that are unrelated.

Check out this FAQ to get all the knowledge you need for accurate cerebral embolism diagnosis coding.

Q: What are my ICD-10 choices for reporting cerebral embolisms without cerebral infarction?

When coding for embolism, your first step is to determine where the embolism is located. Once you confirm the anatomical location of the occlusion, then you can look for the appropriate code.

“While the increased granularity of localizing the site of embolism will help in clinical research by providing greater specificity, there may be efforts to ensure that the location of the embolism matches the procedure location reported,” says Gregory Przybylski, MD, immediate past chairman of neuroscience and director of neurosurgery at the New Jersey Neuroscience Institute, JFK Medical Center in Edison, New Jersey.

For embolism in the three key cerebral arteries; i.e. middle, anterior, and posterior cerebral arteries, you would look to ICD-10-CM codes I66.0 (Occlusion and stenosis of middle cerebral artery), I66.1 (Occlusion and stenosis of anterior cerebral artery), and I66.2 (Occlusion and stenosis of posterior cerebral artery), respectively. Each of these codes has fifth digits for the right, left, bilateral, and unspecified embolism. Make sure you determine which side was occluded before you code for the diagnosis of cerebral embolism.

Here are your ICD-10 choices that specify right, left, and bilateral involvement:

• 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
• I66.09 — Occlusion and stenosis of unspecified middle cerebral artery
• I66.11 — Occlusion and stenosis of right anterior cerebral artery
• I66.12 — Occlusion and stenosis of left anterior cerebral artery
• I66.13 — Occlusion and stenosis of bilateral anterior cerebral arteries
• I66.19 — Occlusion and stenosis of unspecified anterior cerebral artery
• I66.21 — Occlusion and stenosis of right posterior cerebral artery
• I66.22 — Occlusion and stenosis of left posterior cerebral artery
• I66.23 — Occlusion and stenosis of bilateral posterior cerebral arteries
• I66.29 — Occlusion and stenosis of unspecified posterior cerebral artery.

Q: What are some symptoms that may point the provider toward a middle cerebral embolism diagnosis?

When your physician documents that the patient presented with hemiplegia and fixation of the eyes, you should check the clinical note for confirmation of middle cerebral embolism during investigation. “The typical hemiplegia on the side opposite the embolism is seen in middle cerebral artery embolism,” Przybylski says.

Q: What are some symptoms that may point the provider toward an anterior cerebral embolism diagnosis?

When your clinician documents that the patient had conditions like apraxia, anosmia, gaze toward the side of the embolism, urinary incontinence, or grasp or suckling reflexes, you should look for evidence of anterior cerebral artery embolism in the clinical note. “While anterior cerebral artery embolism can have a variety of symptoms, the symptoms here are typical for the frontal lobe involvement,” Przybylski says.

Q: What are some symptoms that may point the provider toward a posterior cerebral embolism diagnosis?

When the posterior circulation is affected, the physician may document complaints like gait imbalance, problems in hand-eye coordination, bumping into objects, repeated falls due to hitting obstacles, acute loss of vision, confusion, posterior cranial headache, and dizziness. “The posterior circulation supplies the cerebellum, resulting in ataxia and dizziness among other symptoms,” Przybylski says.

For example, the physician documents that the patient presents with complaints of repeatedly bumping into objects, hitting obstacles on the roadside, and not being able to see half the printed page when reading. As you read the clinical notes, you see that the site of occlusion is the posterior cerebral artery. So, you would report code I66.29.