Home
Career Stage
Medical Students Residents Attendings CPT Codes Resources Blog Support

84394 Total tau

Pathology & Lab

Also known as: total tau, tau protein, neurodegeneration marker

Quantitative assay of total tau concentration in serum or cerebrospinal fluid, measuring this structural protein.

In Plain Language

brain damage protein test

Clinical Context

Biomarker for neurodegeneration and Alzheimer's disease; elevated levels indicate neuronal damage and cell death.

RVU Information

CPT 84394 does not have a physician work RVU assigned by CMS. Reimbursement for this code is determined by payer-specific fee schedules.

Billing & Documentation

Lab and pathology codes require an order from the treating provider with clinical indication. For molecular pathology and genetic testing, document the specific analytes tested and clinical rationale.

How This Code Compares

This code has a work RVU of 0.00, meaning it does not have a physician work component assigned by CMS. In the Pathology & Lab category, 94% of codes share this characteristic.

Specialties

NeurologyClinical ChemistryPathology

Frequently Asked Questions

What is CPT code 84394?

CPT 84394 (Total tau) is a Pathology & Lab code. Quantitative assay of total tau concentration in serum or cerebrospinal fluid, measuring this structural protein.

Who uses CPT code 84394?

CPT 84394 is used by Neurology, Clinical Chemistry, Pathology. Biomarker for neurodegeneration and Alzheimer's disease; elevated levels indicate neuronal damage and cell death.

When is CPT 84394 used?

Biomarker for neurodegeneration and Alzheimer's disease; elevated levels indicate neuronal damage and cell death.

Track This Code in RVU Edge

Log procedures, calculate wRVUs, and benchmark against national data — all in one app.

CPT® is a registered trademark of the American Medical Association. Data sourced from CMS Physician Fee Schedule RVU26A. Descriptions, synonyms, and clinical context are original content by RVU Edge.