CPT Code for Canalplasty with Ossicular Chain Removal
The appropriate CPT code for this procedure is 69535 (Resection temporal bone, external approach).
This procedure description details a radical temporal bone resection involving complete removal of the external auditory canal skin, ossicular chain removal (malleus and incus), sacrifice of the chorda tympani nerve, and circumferential canalplasty with diamond burr—all components that align with CPT 69535 rather than simpler canalplasty codes.
Procedural Components Analysis
The operative report describes several key elements that determine coding:
- Complete external auditory canal skin removal with frozen section pathology, indicating concern for malignancy or extensive disease requiring radical resection 1, 2
- Ossicular chain removal including division of the incudostapedial joint, removal of the incus, and removal of the malleus with attached tympanic membrane 3
- Scutum removal with curettage 4
- Chorda tympani nerve sacrifice to facilitate exposure 4
- Circumferential canalplasty using diamond burrs to widen the bony canal 1, 2
Coding Rationale
CPT 69535 is the most appropriate code because this represents a lateral temporal bone resection (external approach) rather than a simple canalplasty for exostoses or stenosis. The key distinguishing features include:
- Complete removal of the tympanic membrane and ossicular chain (not preservation-focused surgery) 3
- Frozen section pathology of canal skin suggesting oncologic concern 5
- Extensive bone work beyond simple canal widening 1
- Sacrifice of the chorda tympani nerve, which is not routine in standard canalplasty 4
Alternative Considerations
CPT 69310 (Reconstruction of external auditory canal for congenital atresia, single stage) would be inappropriate as this is not a congenital case 6.
CPT 69320 (Reconstruction external auditory canal for stenosis) would be insufficient coding as it does not capture the ossicular chain removal and radical nature of the dissection 2, 6.
Clinical Context
The procedure described is consistent with management of external auditory canal cholesteatoma or malignancy requiring radical resection. The complete removal of canal skin with frozen section, ossicular chain sacrifice, and extensive bone work all indicate a more aggressive pathology than simple exostoses or benign stenosis 7, 8, 5.