H49.1 Fourth [trochlear] nerve palsy

Non-billable header with 4 child codes.

Applies from H49 Paralytic strabismus

Excludes2 (not included here)

• internal ophthalmoplegia (H52.51-)
• internuclear ophthalmoplegia (H51.2-)
• progressive supranuclear ophthalmoplegia (G23.1)

Codes under H49.1

• H49.10 Fourth [trochlear] nerve palsy, unspecified eye
• H49.11 Fourth [trochlear] nerve palsy, right eye
• H49.12 Fourth [trochlear] nerve palsy, left eye
• H49.13 Fourth [trochlear] nerve palsy, bilateral

Code annotations containing back-references to H49.1

Back-references to H49.1

• Type 2 Excludes: G52 Disorders of other cranial nerves ("paralytic strabismus due to nerve palsy (H49.0-H49.2)")

Diagnosis Index entries for H49.1

• Strabismus (congenital) (nonparalytic) › paralytic › fourth nerve
• Strabismus (congenital) (nonparalytic) › paralytic › trochlear nerve

Nearby codes

• H49.0 Third [oculomotor] nerve palsy
• H49.00 Third [oculomotor] nerve palsy, unspecified eye
• H49.01 Third [oculomotor] nerve palsy, right eye
• H49.02 Third [oculomotor] nerve palsy, left eye
• H49.03 Third [oculomotor] nerve palsy, bilateral
• H49.1 Fourth [trochlear] nerve palsy (this code)
• H49.10 Fourth [trochlear] nerve palsy, unspecified eye
• H49.11 Fourth [trochlear] nerve palsy, right eye
• H49.12 Fourth [trochlear] nerve palsy, left eye
• H49.13 Fourth [trochlear] nerve palsy, bilateral
• H49.2 Sixth [abducent] nerve palsy