H51.20

Internuclear ophthalmoplegia, unspecified eye

FY2027Chapter 7: Diseases of the eye and adnexa/H49–H52 Disorders of ocular muscles, binocular movement, accommodation and refraction

BillableComplete code, valid to report

H51.20 (also written H5120) is a billable ICD-10-CM diagnosis code for internuclear ophthalmoplegia, unspecified eye. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 9 codes in category H51 (Other disorders of binocular movement). Its coding notes include 12 Excludes2 entries.

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (12 notes)
Inherited from H49–H52 Disorders of ocular muscles, binocular movement, accommodation and refraction
  • nystagmus and other irregular eye movements (H55)
Inherited from Chapter 7 Diseases of the eye and adnexa
  • 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

Also from chapter/block level (1 note)
Inherited from Chapter 7 Diseases of the eye and adnexa
  • Use an external cause code following the code for the eye condition, if applicable, to identify the cause of the eye condition