2027 ICD-10-CM Diagnosis Code H50.18Alternating exotropia with other noncomitancies

ICD-10-CM Codes›H00–H59›H49-H52›H50

ICD-10-CM H50.18
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

H50.18 is a billable ICD-10-CM diagnosis code for alternating exotropia with other noncomitancies. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 124 through 125. Coders also document this condition as alternating exotropia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Strabismus.

Code Identity

ICD-10-CM Code
H50.18
Billable Status
Yes — Valid for Submission
Code Describes
Alternating exotropia with other noncomitancies
Short Description
Alternating exotropia with other noncomitancies
Same as the full description in the CMS dataset.
Parent Code
H50.1
Exotropia

Code Classification

ChapterH00–H59Diseases of the eye and adnexa
SectionH49-H52Disorders of ocular muscles, binocular movement, accommodation and refraction
CategoryH50Other strabismus
This CodeH50.18Alternating exotropia with other noncomitancies

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Alternating exotropia
  • Alternating exotropia with noncommitance other than A OR V pattern
  • Alternating exotropia with X AND/OR Y pattern
  • Alternating exotropia with X pattern
  • Alternating exotropia with Y pattern

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to H50.18: its own notes plus those printed at H50.1, block H49-H52, and Chapter 7. A note printed at a category, block or chapter applies to every code under it.

Excludes1

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

From H50.1 Exotropia applies to 13 codes

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 Block H49-H52 Disorders of ocular muscles, binocular movement, accommodation and refraction applies to 150 codes
  • nystagmus and other irregular eye movements (H55)
From Chapter 7 (H00-H59) Diseases of the eye and adnexa applies to 2,677 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • diabetes mellitus related eye conditions (E09.3-, E10.3-, E11.3-, E13.3-)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury (trauma) of eye and orbit (S05.-)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • syphilis related eye disorders (A50.01, A50.3-, A51.43, A52.71)

Notes

General instructions on how these codes are used.

From Chapter 7 (H00-H59) Diseases of the eye and adnexa applies to 2,677 codes
  • Use an external cause code following the code for the eye condition, if applicable, to identify the cause of the eye condition

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name H50.18, its category, or a range that includes it.

Excludes2 1

These codes carry an Excludes2 note naming H50.18: its condition is not part of those codes, and both may be reported when the patient has both.

  • H53.03 Strabismic amblyopia
    strabismus (H50.-) names H50.-, which includes this code

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 EYE007
Strabismus
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Exotropia

    a form of ocular misalignment where the visual axes diverge inappropriately. for example, medial rectus muscle weakness may produce this condition as the affected eye will deviate laterally upon attempted forward gaze. an exotropia occurs due to the relatively unopposed force exerted on the eye by the lateral rectus muscle, which pulls the eye in an outward direction.

Patient EducationClinical

Eye Movement Disorders

When you look at an object, you're using several muscles to move both eyes to focus on it. If you have a problem with the muscles, the eyes don't work properly.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert H50.18 to ICD-9-CMHistory

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

ICD-9-CM
378.18 Alt exotrop w x/y pattrn
Exact Match The mapping is direct, with no qualifiers.

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 H50.18Overview

What is the ICD-10 code for alternating exotropia with other noncomitancies?

The ICD-10-CM code for alternating exotropia with other noncomitancies is H50.18 (sometimes written as H5018). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is H50.18 (Exotropia) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report alternating exotropia with other noncomitancies on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does H50.18 group to?

When alternating exotropia with other noncomitancies is the principal diagnosis on an inpatient stay, it groups to MS-DRG 125, 124, with relative weights from 0.7699 to 1.2470 depending on complications. Higher weights mean higher Medicare reimbursement.

Can H50.18 be reported with a code from H50.33?

Not as a rule. The Excludes1 note at H50.1, which applies to H50.18, lists "intermittent exotropia (H50.33-, H50.34)". 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 H50.18?

Under the General Equivalence Mappings, alternating exotropia with other noncomitancies converts to ICD-9-CM 378.18 (alt exotrop w x/y pattrn). The mapping is a direct match.