S04.20XA — Injury of trochlear nerve, unspecified side, initial encounter
S04.20XA is a billable, specific ICD-10-CM code for injury of trochlear nerve, unspecified side, initial encounter. It is valid for submission on a claim.
7th character "A" — initial encounter
The appropriate 7th character is to be added to each code from category S04
- A
- initial encounter
- D
- subsequent encounter
- S
- sequela
Risk adjustment
S04.20XA does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
S04.20XA is named in 1 Medicare coverage policy — 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A57637Billing and Coding: Visual Field Examination
Code history
S04.20XA has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.
Related codes at this level
Codes that share S04.20. If S04.20XA is not quite right, the correct code is usually one of these.
Questions about S04.20XA
- Is S04.20XA a billable ICD-10-CM code?
- Yes. S04.20XA is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does S04.20XA sit in the tabular list?
- Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Injuries to the head (S00-S09).