Otolaryngology Coding Alert

Tympanoplasty with mastoidectomy offers multiple reporting options.

You're not alone if you've been stumped while coding a tympanoplasty with mastoidectomy -- with the list of similar-looking codes, anyone could get turned around. The key is memorizing which codes represent a wall up and wall down approach, and identifying an ossicular chain reconstruction (OCR). Read on to learn how.

1: Canal Wall Up with OCR Preserves Canal, Removes Ossicles

The hallmark of a canal wall up mastoidectomy is preserving intact the bony posterior external auditory canal.

Description: The surgeon drills the cortex overlying the mastoid bone, identifies the tegmen, sigmoid sinus, and sinodural angle, and then enters Koerner's septum, explains Barbara J. Cobuzzi, MBA, CPC, CPCH, CPC-P, CENTC, CHCC, president of N.J.-based CRN Healthcare Solutions. Once in the antrum, the surgeon exposes the attic and thins down the external auditory canal wall. Lastly, the surgeon removes disease along with the head of the malleus and incus if necessary. She gains access to the middle ear space through the external auditory canal.

OCR: There are two methods of canal wall up tympanoplasties depending on whether it includes (OCR). To determine whether the surgeon performed OCR, look for mention in the op note about use of a graft, prosthesis, or "incus interpositioning" (for instance, the incus is interposed between the malleus and stapes), offers Joseph Edward Leonard, MD, practicing otolaryngologist in Norman, Okla. and CPT committee member with the American Academy of Otolaryngology ��" Head and Neck Surgery. Also, an ossicular chain reconstruction may mention removing the ossicles (the three small bones of the middle ear) in describing the procedure, notes Cobuzzi.

The CPT codes for a wall up approach with OCR, says Cobuzzi, are:

• 69636 -- Tympanoplasty with antrotomy or mastoidotomy (including canalplasty, atticotomy, middle ear surgery, and/or tympanic membrane repair); with ossicular chain reconstruction
• 69637 -- Tympanoplasty with antrotomy or mastoidotomy (including canalplasty, atticotomy, middle ear surgery, and/or tympanic membrane repair); with ossicular chain reconstruction and synthetic prosthesis (e.g., partial ossicular replacement prosthesis [PORP], total ossicular replacement prosthesis [TORP])
• 69642 -- Tympanoplasty with mastoidectomy (including canalplasty, middle ear surgery, tympanic membrane repair); with ossicular chain reconstruction
• 69644 -- Tympanoplasty with mastoidectomy (including canalplasty, middle ear surgery, tympanic membrane repair); with intact or reconstructed canal wall, with ossicular chain reconstruction.

Difference: While you can distinguish 69637 and 69644 by a prosthesis or reconstruction, respectively, 69636 and 69642 appear similar. The difference between 69636 and 69642 is with 69636 the surgeon performs a mastoidotomy, meaning he opens/incises into the mastoid to allow examination and/or removal of limited disease, says Leonard. With 69642, however, the surgeon opens the mastoid by removing the mastoid bone cortex, which is a more extensive procedure generally for more extensive disease,such as a cholesteatoma (385.3x, Cholesteatoma of middle ear and mastoid), he adds.

2: Canal Wall Up no OCR Maintains Canal and Ossicles

If the surgeon maintains the external auditory canal but makes no mention of the incus, you're looking at a wall up approach without OCR, the codes for which are:

• 69635 -- Tympanoplasty with antrotomy or mastoidotomy (including canalplasty, atticotomy, middle ear surgery, and/or tympanic membrane repair); without ossicular chain reconstruction
• 69641 -- Tympanoplasty with mastoidectomy (including canalplasty, middle ear surgery, tympanic membrane repair); without ossicular chain reconstruction
• 69643 -- Tympanoplasty with mastoidectomy (including canalplasty, middle ear surgery, tympanic membrane repair); with intact or reconstructed wall, without ossicular chain reconstruction.

Difference: Again, 69635 and 69641 appear similar. The difference, as above, is 69635 includes a mastoidectomy, while 69641 includes removal of the mastoid cortex bone. Of course, the difference between this set of codes and the above set is here there is no reconstruction of the ossicular chain with a bone or cartilage graft or prosthesis or repositioning of the incus. Also, since there is no ossicular chain reconstruction, the ossicles are preserved, Cobuzzi says.

3: Canal Wall Down Means Radical Mastoidectomy

The terms "radial" or "complete" tell you the surgeon used a canal wall down approach for the mastoidectomy.

Description: In the "canal wall down" mastoid procedure, the surgeon removes the bony posterior external auditory canal. The surgeon performs the steps of the canal wall up mastoidectomy and then drills away the superior and posterior canal wall to the level of the facial nerve, which is identified and left with a thin plate of bone covering it, says Cobuzzi. This approach offers the widest access to the middle ear, antrum, and attic, as well as the mastoid. There are two codes for a wall down approach, one with OCR and one without:

• 69645 -- Tympanoplasty with mastoidectomy (including canalplasty, middle ear surgery, tympanic membrane repair); radical or complete, without ossicular chain reconstruction
• 69646 -- Tympanoplasty with mastoidectomy (including canalplasty, middle ear surgery, tympanic membrane repair); radical or complete, with ossicular chain reconstruction.

Difference: The distinction between the above codes is whether OCR is performed; as above, the procedure without OCR (69645) preserves the ossicles, while the one with OCR (69646) removes the ossicles, notes Cobuzzi.