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v1.0.0
ICD-10 Guide
ICD-10 CodesG45.9

G45.9

Billable

Transient cerebral ischemic attack, unspecified

BILLABLE STATUSYes
IMPLEMENTATION DATEOctober 1, 2015
LAST UPDATED09/05/2025

Code Description

ICD-10 G45.9 is a billable code used to indicate a diagnosis of transient cerebral ischemic attack, unspecified.

Key Diagnostic Point:

A transient cerebral ischemic attack (TIA) is characterized by a temporary period of symptoms similar to those of a stroke. TIAs are caused by a temporary decrease in blood supply to part of the brain, leading to neurological deficits that resolve within 24 hours, typically within minutes to hours. The symptoms may include sudden weakness or numbness in the face, arm, or leg, especially on one side of the body, confusion, trouble speaking or understanding speech, vision problems, and difficulty walking. TIAs are often considered warning signs for future strokes, as they indicate underlying vascular disease. The unspecified nature of G45.9 indicates that the specific cause or type of TIA has not been determined, which can complicate treatment and management strategies. It is crucial for healthcare providers to recognize and address risk factors such as hypertension, diabetes, hyperlipidemia, and lifestyle factors to prevent subsequent cerebrovascular events. The management of a TIA often involves antiplatelet therapy, lifestyle modifications, and sometimes surgical interventions, depending on the underlying causes and risk factors.

Code Complexity Analysis

Complexity Rating: Medium

Medium Complexity

Complexity Factors

  • Unspecified nature can lead to ambiguity in coding.
  • Differentiating between TIA and other cerebrovascular events.
  • Need for thorough documentation to support the diagnosis.
  • Potential overlap with other codes related to cerebrovascular disease.

Audit Risk Factors

  • Inadequate documentation of symptoms and duration.
  • Failure to specify risk factors or underlying conditions.
  • Misclassification with stroke codes.
  • Inconsistent clinical findings in the medical record.

Specialty Focus

Medical Specialties

Neurology

Documentation Requirements

Detailed neurological examination findings, duration of symptoms, and risk factor assessment.

Common Clinical Scenarios

Patients presenting with sudden onset of neurological deficits that resolve quickly.

Billing Considerations

Ensure that all symptoms are documented clearly to support the diagnosis of TIA.

Primary Care

Documentation Requirements

Comprehensive history including risk factors, family history, and lifestyle factors.

Common Clinical Scenarios

Patients with a history of hypertension or diabetes presenting with transient neurological symptoms.

Billing Considerations

Document preventive measures and referrals to specialists for further evaluation.

Coding Guidelines

Inclusion Criteria

Use G45.9 When
  • According to ICD
  • 10 guidelines, G45
  • 9 should be used when the TIA is not specified further
  • Coders should ensure that the documentation supports the diagnosis and that the symptoms have resolved within 24 hours

Exclusion Criteria

Do NOT use G45.9 When
No specific exclusions found.

Related ICD-10 Codes

Related CPT Codes

99214CPT Code

Established patient office visit, level 4

Clinical Scenario

Used for follow-up visits after a TIA.

Documentation Requirements

Document history, examination, and medical decision-making.

Specialty Considerations

Neurology may require additional neurological assessments.

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The transition to ICD-10 has allowed for more specific coding of cerebrovascular events, improving the accuracy of diagnoses and treatment plans. G45.9 provides a clear designation for unspecified TIAs, which can help in tracking and managing patient care.

ICD-9 vs ICD-10

The transition to ICD-10 has allowed for more specific coding of cerebrovascular events, improving the accuracy of diagnoses and treatment plans. G45.9 provides a clear designation for unspecified TIAs, which can help in tracking and managing patient care.

Reimbursement & Billing Impact

The transition to ICD-10 has allowed for more specific coding of cerebrovascular events, improving the accuracy of diagnoses and treatment plans. G45.9 provides a clear designation for unspecified TIAs, which can help in tracking and managing patient care.

Resources

Clinical References

  • •
    American Academy of Neurology

Coding & Billing References

  • •
    American Academy of Neurology

Frequently Asked Questions

What is the difference between a TIA and a stroke?

A TIA is a temporary interruption of blood flow to the brain, causing symptoms that resolve within 24 hours, while a stroke results in permanent damage due to prolonged lack of blood flow.