Otolaryngology Coding Alert

Although numerous local medical review policies (LMRPs) cover Botox injections for laryngeal spasms when administered using laryngoscopy, some carriers may not allow alternative administrative techniques or other diagnoses. Therefore, ethical reimbursement hinges on knowing how to report the various procedures, acceptable diagnosis(es) and billing for other services.

"This is one area that Medicare has not defined at a national level," says Randa Blackwell, coding specialist with the department of otolaryngology at the University of Maryland in Baltimore. "Local carriers decide which diagnosis(es) they will permit for these procedures." Step 1: Determine Administrative Technique Depending on the difficulty of locating the affected muscle and obtaining access to the location, the physician may use a laryngoscope to guide the injection. If the otolaryngologist uses laryngoscopy to inject the toxin into the laryngeal muscles, you should report the appropriate laryngoscopy codes:

31513 Laryngoscopy, indirect; with vocal cord injection 31570 Laryngoscopy, direct, with injection into vocal cord(s), therapeutic 31571 with operating microscope. However, if the doctor can ascertain which muscles are over-contracting and which muscles may be compensating, he may externally inject the neck. In these cases, carriers suggest: 64613 Chemodenervation of muscle(s); cervical spinal muscle(s) (e.g., for spasmodic torticollis)
64640 Destruction by neurolytic agent; other peripheral nerve or branch. Use 64640 only when a carrier instructs you to. Code 64640 describes injecting a peripheral nerve, which does not accurately describe a Botox injection for laryngeal spasms. If your carrier does not specify which injection code to use, you should report unlisted-procedure code 64999 (Unlisted procedure, nervous system). See the box at right for proper filing instructions. Medicare allows one injection per site, regardless of the number of injections made into the site. A site is defined as including muscles of a single contiguous body part, such as a single limb, eyelid, the face or neck. Regardless of the number of injections, the neck muscles constitute one site. Therefore, you should report the procedure code once only. Step 2: Link Acceptable Diagnosis Most carriers accept the laryngoscopy codes (31513, 31570, 31571) when linked with a diagnosis of laryngeal spasms (478.75). But otolaryngologists often use the same technique to administer Botox injections for spastic dysphonia, which the ICD-9 tabular list denotes as 478.79 (Other diseases of larynx, not elsewhere classified; other).

The two terms sometimes seem interchangeable. For instance, Noridian's LMRP for Colorado, North Dakota, South Dakota and Wyoming states that 31513, 31570 and 31571 should be reported with 478.75 "spastic dysphonia." In contrast, Massachusetts, Vermont, Maine and New Hampshire's Part B carrier says "Botulinum Toxin A is considered medically necessary to improve function in patients who have one of the following spastic conditions" and lists "laryngeal dystonia (i.e, adductor spasmodic dysphonia)" as [...]