2026 ICD-10-CM Diagnosis Code T85.321ADisplacement of prosthetic orbit of left eye, initial encounter

ICD-10-CM Codes›S00–T88›T80-T88›T85

ICD-10-CM T85.321A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T85.321A is a billable ICD-10-CM diagnosis code for displacement of prosthetic orbit of left eye, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 919 through 921. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Complication of other surgical or medical care, injury, initial encounter.

Code Identity

ICD-10-CM Code
T85.321A
Billable Status
Yes — Valid for Submission
Code Describes
Displacement of prosthetic orbit of left eye, initial encounter
Short Description
Displacement of prosthetic orbit of left eye, init encntr
Parent Code
T85.321
Displacement of prosthetic orbit of left eye

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT80-T88Complications of surgical and medical care, not elsewhere classified
CategoryT85Complications of other internal prosthetic devices, implants and grafts
This CodeT85.321ADisplacement of prosthetic orbit of left eye, initial encounter

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Complications of other internal prosthetic devices, implants and grafts (T85). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INJ037
Complication of other surgical or medical care, injury, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Convert T85.321A to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
996.59 Malfunc oth device/graft
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About T85.321AOverview

Is T85.321A (Displacement of prosthetic orbit of left eye) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report displacement of prosthetic orbit of left eye, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in T85.321A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for displacement of prosthetic orbit of left eye, such as an emergency visit or first evaluation.

What MS-DRG does T85.321A group to?

When displacement of prosthetic orbit of left eye, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 919, 920, 921, with relative weights from 0.6884 to 1.8308 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of T85.321A?

Under the General Equivalence Mappings, displacement of prosthetic orbit of left eye, initial encounter converts to ICD-9-CM 996.59 (malfunc oth device/graft). The mapping is approximate, so confirm the match fits the documentation.