2027 ICD-10-CM Diagnosis Code R94.128Abnormal results of other function studies of ear and other special senses

ICD-10-CM Codes›R00–R99›R90-R94›R94

ICD-10-CM R94.128
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

R94.128 is a billable ICD-10-CM diagnosis code for abnormal results of other function studies of ear and other special senses. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 91 through 93. As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established. Coders also document this condition as abnormal nasal potential difference. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abnormal findings without diagnosis.

Code Identity

ICD-10-CM Code
R94.128
Billable Status
Yes — Valid for Submission
Code Describes
Abnormal results of other function studies of ear and other special senses
Short Description
Abn results of function studies of ear and oth sp senses
Parent Code
R94.12
Abnormal results of function studies of ear and other special senses

Code Classification

ChapterR00–R99Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
SectionR90-R94Abnormal findings on diagnostic imaging and in function studies, without diagnosis
CategoryR94Abnormal results of function studies
This CodeR94.128Abnormal results of other function studies of ear and other special senses

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abnormal nasal potential difference
  • Deteriorating hearing
  • Hearing change
  • Hearing worse
  • Middle ear fistula sign positive
  • Tympanogram abnormal

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to R94.128: its own notes plus those printed at R94, block R90-R94, and Chapter 18. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From R94 Abnormal results of function studies applies to 23 codes
  • abnormal results of radionuclide [radioisotope] uptake studies
  • abnormal results of scintigraphy
From Block R90-R94 Abnormal findings on diagnostic imaging and in function studies, without diagnosis applies to 64 codes
  • nonspecific abnormal findings on diagnostic imaging by computerized axial tomography [CAT scan]
  • nonspecific abnormal findings on diagnostic imaging by magnetic resonance imaging [MRI][NMR]
  • nonspecific abnormal findings on diagnostic imaging by positron emission tomography [PET scan]
  • nonspecific abnormal findings on diagnostic imaging by thermography
  • nonspecific abnormal findings on diagnostic imaging by ultrasound [echogram]
  • nonspecific abnormal findings on diagnostic imaging by X-ray examination

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Block R90-R94 Abnormal findings on diagnostic imaging and in function studies, without diagnosis applies to 64 codes
  • abnormal findings on antenatal screening of mother (O28.-)
  • diagnostic abnormal findings classified elsewhere - see Alphabetical Index

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 18 (R00-R99) Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified applies to 774 codes
  • abnormal findings on antenatal screening of mother (O28.-)
  • certain conditions originating in the perinatal period (P04-P96)
  • signs and symptoms classified in the body system chapters
  • signs and symptoms of breast (N63, N64.5)

Notes

General instructions on how these codes are used.

From Chapter 18 (R00-R99) Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified applies to 774 codes
  • This chapter includes symptoms, signs, abnormal results of clinical or other investigative procedures, and ill-defined conditions regarding which no diagnosis classifiable elsewhere is recorded.
  • Signs and symptoms that point rather definitely to a given diagnosis have been assigned to a category in other chapters of the classification. In general, categories in this chapter include the less well-defined conditions and symptoms that, without the necessary study of the case to establish a final diagnosis, point perhaps equally to two or more diseases or to two or more systems of the body. Practically all categories in the chapter could be designated 'not otherwise specified', 'unknown etiology' or 'transient'. The Alphabetical Index should be consulted to determine which symptoms and signs are to be allocated here and which to other chapters. The residual subcategories, numbered .8, are generally provided for other relevant symptoms that cannot be allocated elsewhere in the classification.
  • The conditions and signs or symptoms included in categories R00-R94 consist of:
  • (a) cases for which no more specific diagnosis can be made even after all the facts bearing on the case have been investigated;
  • (b) signs or symptoms existing at the time of initial encounter that proved to be transient and whose causes could not be determined;
  • (c) provisional diagnosis in a patient who failed to return for further investigation or care;
  • (d) cases referred elsewhere for investigation or treatment before the diagnosis was made;
  • (e) cases in which a more precise diagnosis was not available for any other reason;
  • (f) certain symptoms, for which supplementary information is provided, that represent important problems in medical care in their own right.

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

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

CCSR SYM017
Abnormal findings without diagnosis
Default principal diagnosis: inpatient Yes · outpatient Yes

Convert R94.128 to ICD-9-CMHistory

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

ICD-9-CM
794.19 Abn periph nerv stud NEC
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About R94.128Overview

Is R94.128 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report abnormal results of other function studies of ear and other special senses on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does R94.128 group to?

When abnormal results of other function studies of ear and other special senses is the principal diagnosis on an inpatient stay, it groups to MS-DRG 91, 92, 93, with relative weights from 0.7783 to 1.7050 depending on complications. Higher weights mean higher Medicare reimbursement.

Can R94.128 be a principal diagnosis?

Use it with care. This is a symptom code, so once a definitive diagnosis explaining the abnormal results of other function studies of ear and other special senses is established, that condition takes the principal position instead.

Can R94.128 be reported with a code from O28?

Not as a rule. The Excludes1 note at block R90-R94, which applies to R94.128, lists "abnormal findings on antenatal screening of mother (O28.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What is the ICD-9 equivalent of R94.128?

Under the General Equivalence Mappings, abnormal results of other function studies of ear and other special senses converts to ICD-9-CM 794.19 (abn periph nerv stud NEC). The mapping is approximate, so confirm the match fits the documentation.