2025 CPT code 81184
(Active) Effective Date: N/A Revision Date: N/A Laboratory - Molecular Pathology Procedures Pathology and Laboratory Feed
Analysis of the CACNA1A gene to identify abnormal alleles, particularly expanded ones, often related to spinocerebellar ataxia.
Modifier 26 may be used if only the interpretation and report are performed by the physician.Other modifiers may apply depending on the specific circumstances of the service.
Medical necessity for 81184 is established based on the patient's clinical presentation and the suspicion of a genetic disorder like SCA6 or when family history warrants carrier status evaluation.Appropriate clinical indicators must be documented to justify the testing.
The clinical responsibility lies with the laboratory analyst who performs all technical aspects of the test, from specimen processing to data analysis. A physician or other qualified professional may provide interpretation of the results if separately ordered.
In simple words: This lab test checks for changes in a specific gene (CACNA1A) that can cause problems with coordination and movement, often seen in a condition called spinocerebellar ataxia. The test looks for unusual changes in the gene's structure, helping doctors diagnose the condition or determine if someone carries the gene.
This code encompasses the laboratory analysis of the calcium voltage-gated channel subunit alpha1 A gene (CACNA1A) to detect and characterize abnormal alleles, primarily those with expanded sequences (e.g., CAG trinucleotide repeat expansions). The procedure includes all analytical steps, from nucleic acid extraction and purification to amplification and detection techniques such as PCR.This test is often used to aid in the diagnosis of spinocerebellar ataxia type 6 (SCA6) and to determine carrier status.Results may require interpretation by a qualified healthcare professional (modifier 26 may be added if only interpretation is performed).
Example 1: A patient presents with progressive ataxia, dysarthria, and nystagmus.The physician orders 81184 to investigate a suspected diagnosis of SCA6., A family history of SCA6 prompts a physician to order 81184 for a patient with mild neurological symptoms to assess for carrier status., A patient with unexplained neurological symptoms undergoes genetic testing, and 81184 is ordered as part of a broader panel to investigate possible genetic causes of their condition.
* Patient demographics and clinical history.* Detailed description of symptoms and neurological examination findings.* Family history of neurological disorders.* Specimen collection and handling documentation (e.g., blood draw date, time, and storage conditions).* Complete laboratory report including the analytical methods used and results.
** Specific details on the methods used for gene analysis (e.g., PCR, sequencing) might be included in the laboratory report but are not encoded in the CPT code itself.Payer specific billing rules may vary.
- Payment Status: Active
- Modifier TC rule: Not applicable; this is a comprehensive laboratory analysis.
- Specialties:Neurology, Genetics, Clinical Laboratory
- Place of Service:Laboratory, Hospital, Physician's Office