G2189 Head Imaging (HCPCS) Reimbursement & Policy

HCPCS Level II code G2189 denotes diagnostic head imaging performed when a patient presents with an abnormal neurologic examination. Nationally, this code captures imaging services ordered for acute neurologic findings that may indicate stroke, intracranial hemorrhage, focal deficits, or other urgent neurologic conditions. Accurate use of G2189 ensures appropriate classification of medically necessary neuroimaging and assists payers and providers in distinguishing imaging triggered by clinical examination versus routine or screening imaging.

Key payers relevant to national coverage and policy include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of clinical context for use of G2189, typical sites of service where the code applies, and the scope of payer considerations. The publication also summarizes available benchmarks and policy updates when present and notes where input data are not available.

This summary is intended to provide clinicians, coding professionals, and policy analysts with a concise reference to the clinical intent of HCPCS Level II code G2189, its operational settings, and the payer landscape commonly involved in coverage decisions for urgent head imaging following an abnormal neurologic exam.

Billing Code Overview

HCPCS Level II code G2189 describes imaging for patients who have clinical indications for head imaging due to an abnormal neurologic exam. This represents diagnostic imaging services focused on evaluating acute or concerning neurologic findings identified on clinical examination.

Service type: Diagnostic head imaging (neuroimaging) driven by clinical neurologic findings
Typical site of service: Emergency department, hospital outpatient imaging departments, or inpatient settings where urgent neuroimaging is indicated

Data not available in the input.

Clinical Context

A 68-year-old man with hypertension and atrial fibrillation presents to the emergency department with new-onset left-sided weakness and expressive aphasia. The triage nurse documents focal neurologic deficits on initial exam. The emergency physician performs a focused neurologic exam, documents asymmetric strength, facial droop, and language disturbance, and orders urgent non-contrast head imaging to evaluate for acute intracranial hemorrhage or ischemic stroke. The imaging study is performed in the hospital radiology department; results are interpreted by a radiologist and communicated to the treating team for immediate treatment decisions such as thrombolysis or neurosurgical consultation. Typical site of service is hospital-based outpatient or inpatient radiology (emergency department/radiology suite). The service type is urgent/emergent diagnostic imaging of the head for abnormal neurologic exam, coded under G2189 when applicable to payer billing policies. Common clinical workflow steps: initial clinician evaluation and documentation of abnormal neurologic exam, order placement for head imaging, transport to radiology, image acquisition (CT or MRI as ordered), radiologist interpretation, and documentation of findings and disposition plan.

Coding Specifications

Modifier	Description	When to Use
`22`	Increased procedural services	Use when work, time, or technical difficulty substantially exceeds typical for head imaging interpretation documentation and payer allows modifier for imaging professional claims.

Taxonomy Code	Specialty	Notes
`2084P0800X`	Diagnostic Radiology	Primary specialty performing head imaging and interpretation.
`207RH0002X`	Emergency Medicine	Clinicians who evaluate acute neurologic deficits and order urgent head imaging.
`207L00000X`	Neurology	Consults for focal deficits and ongoing management; may order advanced imaging.
`208100000X`	Vascular Neurology / Stroke Neurology	Specialists involved in acute stroke pathways and imaging-driven treatment decisions.
`362A00000X`	Neurosurgery	May be involved when imaging reveals surgical lesions requiring intervention.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`I63.9`	Cerebral infarction, unspecified	Common cause of acute focal neurologic deficits prompting head imaging to evaluate ischemic stroke.
`I61.9`	Intracerebral hemorrhage, unspecified	Presents with focal deficits or altered exam; imaging required to identify hemorrhage prior to treatment.
`G45.9`	Transient cerebral ischemic attack, unspecified	Brief focal neurologic signs often imaged to exclude infarction or hemorrhage.
`R41.840`	Attention and concentration deficit	Focal neurologic changes or altered mental status may prompt head imaging.
`R47.01`	Aphasia	Language disturbance is a focal neurologic sign that triggers urgent head imaging in stroke evaluation.
`R29.6`	Recurrent falls	Falls with neurologic findings warrant head imaging to assess for acute intracranial injury.
`S06.0X0A`	Concussion without loss of consciousness, initial encounter	Head trauma with abnormal neurologic exam may be evaluated with head imaging.
`G93.4`	Encephalopathy, unspecified	Altered mental status with focal signs may require imaging to assess structural causes.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`70450`	Computed tomography, head or brain; without contrast material	Common initial imaging for acute neurologic deficits to exclude hemorrhage prior to therapy.
`70460`	Computed tomography, head or brain; with contrast material(s)	Used when contrast enhancement is indicated to evaluate mass, infection, or vascular lesions after initial noncontrast CT.
`70551`	Magnetic resonance imaging, brain (including brain stem); without contrast	Utilized for detailed evaluation of ischemia, demyelination, or other parenchymal abnormalities when MRI is indicated.
`70553`	Magnetic resonance imaging, brain (including brain stem); without and with contrast	Performed when both noncontrast and contrast sequences are needed for comprehensive assessment.
`74174`	Computed tomography, abdomen and pelvis with contrast (example for multisystem trauma)	Sometimes performed in multi‑trauma evaluations when head imaging is part of a broader diagnostic workup; listed as an example of commonly co‑performed imaging in emergency settings.

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Summary & Overview

HCPCS G2189: Head Imaging for Abnormal Neurologic Exam