Summary & Overview
CPT 76390: Magnetic Resonance Spectroscopy (MRS)
CPT code 76390 designates magnetic resonance spectroscopy (MRS), an advanced diagnostic imaging technique that measures the chemical composition and metabolism of tissues. MRS supplements conventional MRI by providing metabolic and biochemical information used in assessing brain disorders, tumor malignancy, and metabolic diseases of muscle and nervous tissue. Nationally, MRS is an important tool for diagnostic precision in neurology and oncology and can influence care planning and further diagnostic testing.
Key payers addressed in this summary include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of clinical indications and service context, typical sites of service, and the common payer landscape for MRS billing. The publication summarizes benchmarking and coverage themes relevant to CPT code 76390, highlights policy and coding considerations that affect reimbursement and claims processing, and provides clinical context on when MRS is used alongside MRI.
This briefing is intended for national audiences including clinicians, billing professionals, and policy analysts seeking concise information on CPT code 76390, its clinical role, and payer coverage patterns. Data not provided in the input (such as specific coverage policies, utilization metrics, or associated taxonomies and ICD-10 codes) are noted as unavailable.
Billing Code Overview
CPT code 76390 describes magnetic resonance spectroscopy (MRS), a diagnostic imaging technique used to detect and identify the chemical composition of diseased tissue and to study organ metabolism. MRS evaluates biochemical and metabolic changes in tissues, complementing conventional magnetic resonance imaging (MRI) by monitoring body chemistry rather than primarily depicting anatomical structure.
Service Type: Diagnostic imaging — magnetic resonance spectroscopy (MRS)
Typical Site of Service: Hospital outpatient radiology departments, freestanding imaging centers, and tertiary care centers
Clinical & Coding Specifications
Clinical Context
A 52-year-old patient presents with progressive headaches, new focal neurologic deficits, and an enhancing intracranial lesion on prior MRI. The neurologist orders magnetic resonance spectroscopy to characterize the lesion chemistry and help distinguish high-grade tumor from radiation necrosis or abscess. The patient arrives at an outpatient imaging center with prior MRI sequences available. The MRI technologist performs the routine MRI brain protocol, then the radiologist or a trained MR technologist acquires single-voxel and/or multi-voxel proton MRS sequences centered on the lesion. The radiologist reviews spectral peaks (choline, creatine, N-acetylaspartate, lactate/lipids) and documents metabolic ratios and interpretation. Results are communicated to the referring neurologist or neurosurgeon for treatment planning, biopsy guidance, or further metabolic evaluation. Typical site of service is an outpatient imaging center or hospital outpatient radiology department; inpatient performance occurs when the patient is admitted for neurologic evaluation or preoperative planning.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | When reporting the interpreting physicians service separate from technical facility charge |
TC | Technical component | When reporting only the imaging equipment/technologist portion without physician interpretation |
52 | Reduced services | When MRS is partially performed or limited compared with full protocol |
59 | Distinct procedural service | When MRS is performed during the same session as another distinct MRI sequence that is separately reportable |
76 | Repeat procedure by same physician | When the same physician repeats the MRS study during the same encounter |
77 | Repeat procedure by another physician | When a different physician repeats the MRS study during the same encounter |
78 | Return to operating/procedure room following initial service | Rare, but used if MRS-guided intraoperative procedure requires return visit within global period |
80 | Assistant surgeon | If an assistant surgeon is billed for an operative procedure related to image-guided intervention (contextual, limited applicability) |
22 | Increased procedural services | When the MRS requires substantially greater effort or time than usual and documentation supports unusual complexity |
52 | Reduced services | When portions of the MRS protocol are omitted due to patient condition (listed again for emphasis if applicable) |
QX | Certified Registered Nurse Anesthetist (CRNA) with non‑physician direction | If anesthesia services are furnished during the MRI by a CRNA under certain payer rules |
AS | Physician assistant, nurse practitioner, or clinical nurse specialist services in ambulatory surgical center | If such provider performs or assists in related services in an ASC setting |
59 | Distinct procedural service | (Repeated if needed to indicate alternates) |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
| 2084P0800X | Diagnostic Radiology | Radiologists interpret MRS studies and produce final reports |
| 2085R0201X | Neurology | Neurologists order MRS for metabolic evaluation of brain disorders |
| 207L00000X | Neurosurgery | Neurosurgeons use MRS for preoperative tumor characterization and planning |
| 2086S0121X | Nuclear Medicine | Nuclear medicine physicians may collaborate on metabolic imaging correlation |
| 364S00000X | Clinical Neurophysiology | Specialists may correlate MRS with electrophysiology in complex cases |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
C71.9 | Malignant neoplasm of brain, unspecified | MRS helps assess tumor metabolic profile and grade, informing management |
G93.5 | Compression of brain (including increased intracranial pressure) | Metabolic changes may be evaluated to clarify etiology when structural imaging is inconclusive |
G35 | Multiple sclerosis | MRS can detect metabolic markers of demyelination and chronic lesions |
A41.9 | Sepsis, unspecified organism (brain abscess context) | When infectious process is suspected, MRS can help differentiate abscess from tumor by identifying amino acid and lactate peaks |
E88.81 | Gaucher disease (example of metabolic disorder) | MRS can evaluate neurometabolic diseases and monitor biochemical changes in muscle and nervous system |
I63.9 | Cerebral infarction, unspecified | MRS may identify lactate peaks and metabolic markers in subacute ischemic injury |
R51 | Headache | As part of the workup for new or changing headaches with an indeterminate lesion, MRS provides metabolic information |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
70551 | Magnetic resonance imaging, brain; without contrast material, followed by contrast and further sequences (complete brain MRI protocol may vary) | Commonly performed before or with MRS; MRS is often an additional spectroscopy sequence to a diagnostic brain MRI |
70553 | Magnetic resonance imaging, brain; without and with contrast material, including diffusion, perfusion, and other advanced sequences as indicated | Provides structural and advanced sequences that complement metabolic information from MRS |
0159T | Magnetic resonance spectroscopy (MRS), single voxel or multivoxel; technical and professional components (sometimes reported for specialized MRS techniques—note: payer acceptance varies) | Specific code sometimes used for advanced or research MRS techniques; relates directly to MRS acquisition and interpretation |
77012 | Magnetic resonance guidance for needle placement | Used when MRS findings guide stereotactic biopsy; image guidance for tissue sampling may follow MRS interpretation |
88305 | Level IV surgical pathology, gross and microscopic examination | Pathology code for tissue obtained after biopsy guided by MRS findings; used in workflow after surgical sampling |