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ICD-10 Guide
ICD-10 CodesI66.0

I66.0

Non-billable

Occlusion and stenosis of middle cerebral artery

BILLABLE STATUSNo
IMPLEMENTATION DATEOctober 1, 2015
LAST UPDATED09/06/2025

Code Description

ICD-10 I66.0 is a used to indicate a diagnosis of occlusion and stenosis of middle cerebral artery.

Key Diagnostic Point:

I66.0 refers to the occlusion and stenosis of the middle cerebral artery (MCA), a critical vessel supplying blood to significant portions of the brain. Clinically, patients may present with symptoms such as sudden weakness or numbness, particularly on one side of the body, difficulty speaking, and visual disturbances. The MCA is responsible for supplying blood to areas of the brain that control motor functions and speech, making occlusion or stenosis particularly impactful. Disease progression can lead to ischemic strokes, which may result in permanent neurological deficits. Diagnostic considerations include imaging studies such as CT or MRI to visualize the occlusion and assess the extent of ischemic damage. Doppler ultrasound may also be utilized to evaluate blood flow. Early identification and management are crucial to prevent further complications and improve patient outcomes.

Code Complexity Analysis

Complexity Rating: Medium

Medium Complexity

Complexity Factors

  • Diagnostic complexity: Requires imaging and clinical correlation.
  • Treatment complexity: May involve medical management, surgical interventions, or rehabilitation.
  • Documentation requirements: Detailed clinical notes and imaging reports are necessary.
  • Coding specificity: Requires precise coding to differentiate from other cerebrovascular conditions.

Audit Risk Factors

  • Common coding errors: Misidentification of the artery involved.
  • Documentation gaps: Incomplete clinical notes or lack of imaging reports.
  • Billing challenges: Potential denials due to insufficient documentation or incorrect coding.

Specialty Focus

Medical Specialties

Neurology

Documentation Requirements

Standard ICD-10-CM documentation requirements apply

Common Clinical Scenarios

Various clinical presentations within this specialty area

Billing Considerations

Follow specialty-specific billing guidelines

Interventional Radiology

Documentation Requirements

Standard ICD-10-CM documentation requirements apply

Common Clinical Scenarios

Various clinical presentations within this specialty area

Billing Considerations

Follow specialty-specific billing guidelines

Related ICD-10 Codes

Related CPT Codes

CPT Code

Clinical Scenario

Documentation Requirements

CPT Code

Clinical Scenario

Documentation Requirements

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The clinical significance of I66.0 is profound, as occlusion and stenosis of the MCA can lead to significant morbidity and mortality. The impact on population health is substantial, given the prevalence of cerebrovascular diseases. Quality measures often focus on timely diagnosis and intervention to minimize long-term disability. Understanding healthcare utilization patterns related to this condition is essential for improving care delivery and outcomes in affected populations.

ICD-9 vs ICD-10

The clinical significance of I66.0 is profound, as occlusion and stenosis of the MCA can lead to significant morbidity and mortality. The impact on population health is substantial, given the prevalence of cerebrovascular diseases. Quality measures often focus on timely diagnosis and intervention to minimize long-term disability. Understanding healthcare utilization patterns related to this condition is essential for improving care delivery and outcomes in affected populations.

Reimbursement & Billing Impact

Reimbursement considerations may vary based on the severity of the condition and the interventions performed. Common denials can occur if documentation does not clearly support the diagnosis or if the coding does not align with the services rendered. Best practices include ensuring that all clinical notes are thorough and that coding is precise to avoid discrepancies during audits.

Resources

Clinical References

  • •
    ICD-10 Official Guidelines for I00-I99
  • •
    Clinical Documentation Requirements

Coding & Billing References

  • •
    ICD-10 Official Guidelines for I00-I99
  • •
    Clinical Documentation Requirements

Frequently Asked Questions

What specific conditions are covered by I66.0?

I66.0 covers occlusion and stenosis specifically affecting the middle cerebral artery, which can result from atherosclerosis, embolism, or other vascular diseases. It is crucial to differentiate this from occlusions in other cerebral arteries.

When should I66.0 be used instead of related codes?

I66.0 should be used when the clinical scenario specifically involves the middle cerebral artery. If the occlusion or stenosis affects other arteries, such as the anterior or posterior cerebral arteries, different codes should be selected.

What documentation supports I66.0?

Documentation should include clinical findings, imaging results confirming the occlusion or stenosis of the MCA, and any relevant patient history that supports the diagnosis.