2022 ICD-10-CM Code I66.02

Occlusion and stenosis of left middle cerebral artery

Version 2021

Valid for Submission

ICD-10:I66.02
Short Description:Occlusion and stenosis of left middle cerebral artery
Long Description:Occlusion and stenosis of left middle cerebral artery

Code Classification

  • Diseases of the circulatory system (I00–I99)
    • Cerebrovascular diseases (I60-I69)
      • Occls and stenosis of cereb art, not rslt in cerebral infrc (I66)

I66.02 is a billable diagnosis code used to specify a medical diagnosis of occlusion and stenosis of left middle cerebral artery. The code I66.02 is valid during the fiscal year 2022 from October 01, 2021 through September 30, 2022 for the submission of HIPAA-covered transactions.

The ICD-10-CM code I66.02 might also be used to specify conditions or terms like cerebral thrombosis, embolism of middle cerebral artery, embolus of left middle cerebral artery, middle cerebral artery occlusion, occlusion of left middle cerebral artery , occlusion of left middle cerebral artery by embolus, etc.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Convert I66.02 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code I66.02 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.

Information for Patients


Brain Diseases

The brain is the control center of the body. It controls thoughts, memory, speech, and movement. It regulates the function of many organs. When the brain is healthy, it works quickly and automatically. However, when problems occur, the results can be devastating.

Inflammation in the brain can lead to problems such as vision loss, weakness and paralysis. Loss of brain cells, which happens if you suffer a stroke, can affect your ability to think clearly. Brain tumors can also press on nerves and affect brain function. Some brain diseases are genetic. And we do not know what causes some brain diseases, such as Alzheimer's disease.

The symptoms of brain diseases vary widely depending on the specific problem. In some cases, damage is permanent. In other cases, treatments such as surgery, medicines, or physical therapy can correct the source of the problem or improve symptoms.


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Vascular Diseases

What are vascular diseases?

Your vascular system is your body's network of blood vessels. It includes your

Vascular diseases are conditions which affect your vascular system. They are common and can be serious. Some types include

What causes vascular diseases?

The causes of vascular diseases depend on the specific disease. These causes include

Sometimes the cause is unknown.

Who is at risk for vascular diseases?

The risk factors for vascular diseases can vary, depending on the specific disease. But some of the more common risk factors include

What are the symptoms of vascular diseases?

The symptoms for each disease are different.

How are vascular diseases diagnosed?

To make a diagnosis, your health care provider will do a physical exam and ask about your symptoms and medical history. You may have imaging tests and/or blood tests.

How are vascular diseases treated?

Which treatment you get depends on which vascular disease you have and how severe it is. Types of treatments for vascular diseases include

Can vascular diseases be prevented?

There are steps you can take to help prevent vascular diseases:


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Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)