0N864ZZ
Division Temporal Bone, Left to No Qualifier with No Device, Percutaneous Endoscopic Approach
Procedural Specifications
| Clinical Axis | Detail Definition |
|---|---|
| Section | 0 Medical and Surgical |
| Body System | N Head and Facial Bones |
| Operation | 8 Division |
| Body Part | 6 Temporal Bone, Left |
| Approach | 4 Percutaneous Endoscopic |
| Device | Z No Device |
| Qualifier | Z No Qualifier |
Operation Definition
Cutting into a body part, without draining fluids and/or gases from the body part, in order to separate or transect a body part
Procedure Overview
This family covers cutting into the skull or facial bones to separate or transect a structure, without draining any fluid or gas as part of the procedure. A typical example is an osteotomy performed to reposition facial bones during craniofacial reconstructive surgery, or cutting through a cranial suture or bony bridge to free up structures for later repositioning, without any component involving fluid evacuation.
These procedures are often a preparatory step within a larger reconstructive operation, such as orthognathic or craniofacial surgery, where bone must be divided before it can be moved, realigned, or grafted into a new position.
Anatomy & Axis Detail
Temporal Bone, Left
The left temporal bone contains the external, middle, and inner ear structures along with a portion of the facial nerve canal, and forms part of the lateral skull base. Division of this bone - cutting through it without removing tissue - is performed in select skull base approaches or reconstructive procedures where surgical access requires separating the bone along a planned line. Given the temporal bone's dense concentration of critical structures, including the facial nerve, labyrinth, and adjacent venous sinuses, this cut demands meticulous preoperative planning, often with image guidance, to avoid injury. The code captures only the act of dividing the bone, separate from any excision, destruction, or repair of the ear or nerve structures that may accompany the same operative episode.
Approach: Percutaneous Endoscopic
Percutaneous Endoscopic combines a puncture through skin or mucous membrane with insertion of an endoscope to visualize the procedure internally, as in laparoscopic cholecystectomy. It is distinguished from plain Percutaneous by the presence of scope-guided visualization, and from Via Natural or Artificial Opening Endoscopic by its route being a new puncture rather than an existing orifice or stoma.
Coding & Documentation
Documentation should describe the bone being cut through or transected to separate it into distinct segments, with no mention of draining fluid or gas as part of that specific step. Coders need to distinguish the cutting portion of a larger procedure, which is coded as Division, from any accompanying drainage, which would require its own separate code. A common error is coding an osteotomy as Division when the primary intent and outcome documented is actually repositioning the bone, which is more accurately captured under Reposition, with Division reserved only when separation itself is the distinct, standalone objective.
