2025 ICD-10-CM code I66.8
(Active) Effective Date: N/A Diseases of the circulatory system - Occlusion and stenosis of other cerebral arteries 9 Feed
Occlusion and stenosis of other cerebral arteries. This includes conditions such as embolism, narrowing, obstruction (complete or partial), and thrombosis of cerebral arteries, excluding those causing cerebral infarction.
Medical necessity must be established by documenting the clinical signs, symptoms, or diagnostic findings indicating a cerebrovascular condition. This information supports the need for further investigation, treatment, or monitoring.
Clinicians responsible for diagnosing and managing cerebrovascular diseases, including neurologists, interventional radiologists, and vascular surgeons, would use this code.
In simple words: This code refers to a blockage or narrowing of blood vessels in the brain, excluding the major arteries. It covers various types of blockages, but not those that have already caused a stroke.
Occlusion and stenosis of other cerebral arteries, including perforating arteries.This code describes a blockage or narrowing of the cerebral arteries, other than the middle, anterior, posterior, cerebellar, or multiple and bilateral cerebral arteries. It encompasses various causes like embolism, thrombosis, and narrowing. This code excludes occlusion or stenosis leading to cerebral infarction (I63.-).
Example 1: A patient presents with symptoms suggestive of reduced blood flow to the brain, and imaging reveals a blockage in a small perforating artery deep within the brain. This would be coded as I66.8., A patient experiences temporary neurological symptoms, and diagnostic tests identify a stenosis (narrowing) of a cerebral artery not classified under other I66 subcategories. This would be coded as I66.8., A patient with a history of atherosclerosis is found to have multiple small blockages in various smaller cerebral arteries, none of which have caused a stroke. This scenario could be coded as I66.8, although I66.4 might be considered if the blockages are bilateral.
Documentation should clearly specify the affected artery, the nature of the occlusion or stenosis (e.g., thrombosis, embolism, narrowing), the location of the blockage (e.g., proximal, distal, cerebral portion of internal carotid), and the absence of cerebral infarction. Any associated symptoms and the diagnostic methods used (e.g., angiography, imaging) should also be documented.Distinguishing between the cerebral and precerebral portions of the internal carotid artery is crucial for accurate coding.
** It is important to distinguish this code from I65.2, which refers to occlusion and stenosis of the carotid artery. If documentation indicates the affected portion of the internal carotid artery is cerebral (e.g., supraclinoid, paraclinoid, terminal), use I66.8; if it is precerebral (e.g., proximal), use I65.2. If the documentation is unclear, query the provider for clarification.
- Payment Status: Active
- Specialties:Neurology, Interventional Radiology, Vascular Surgery, Cardiology
- Place of Service:Inpatient Hospital, On Campus-Outpatient Hospital,Off Campus-Outpatient Hospital, Office, Independent Clinic