2020 ICD-10-CM Diagnosis Code G90.2

Horner's syndrome

    2016 2017 2018 2019 2020 Billable/Specific Code
  • G90.2 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2020 edition of ICD-10-CM G90.2 became effective on October 1, 2019.
  • This is the American ICD-10-CM version of G90.2 - other international versions of ICD-10 G90.2 may differ.
Applicable To
  • Bernard(-Horner) syndrome
  • Cervical sympathetic dystrophy or paralysis
The following code(s) above G90.2 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to G90.2:
  • G00-G99
    2020 ICD-10-CM Range G00-G99

    Diseases of the nervous system

    Type 2 Excludes
    • 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)
    • endocrine, nutritional and metabolic diseases (E00-E88)
    • 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)
    Diseases of the nervous system
  • G90
    ICD-10-CM Diagnosis Code G90

    Disorders of autonomic nervous system

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • dysfunction of the autonomic nervous system due to alcohol (G31.2)
    Disorders of autonomic nervous system
Approximate Synonyms
  • Horners syndrome
  • Left cervical sympathetic dystrophy
  • Right cervical sympathetic dystrophy
Clinical Information
  • A condition in which one side of the face is flushed, does not produce sweat, and has a constricted pupil and drooping eyelid. It can be caused by an injury to, or paralysis of, nerves in the neck, or by a tumor.
  • A syndrome associated with defective sympathetic innervation to one side of the face, including the eye. Clinical features include miosis; mild blepharoptosis; and hemifacial anhidrosis (decreased sweating)(see hypohidrosis). Lesions of the brain stem; cervical spinal cord; first thoracic nerve root; apex of the lung; carotid artery; cavernous sinus; and apex of the orbit may cause this condition. (from miller et al., clinical neuro-ophthalmology, 4th ed, pp500-11)
  • Syndrome associated with defective sympathetic innervation to one side of the face, including the eye; clinical features include miosis, mild blepharoptosis, and hemifacial anhidrosis (decreased sweating); lesions of the brain stem, cervical spinal cord, first thoracic nerve root, apex of the lung, carotid artery, cavernous sinus, and apex of the orbit may cause this condition.
ICD-10-CM G90.2 is grouped within Diagnostic Related Group(s) (MS-DRG v37.0):
  • 073 Cranial and peripheral nerve disorders with mcc
  • 074 Cranial and peripheral nerve disorders without mcc

Convert G90.2 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change

Diagnosis Index entries containing back-references to G90.2:

ICD-10-CM Codes Adjacent To G90.2
G89.22 Chronic post-thoracotomy pain
G89.28 Other chronic postprocedural pain
G89.29 Other chronic pain
G89.3 Neoplasm related pain (acute) (chronic)
G89.4 Chronic pain syndrome
G90 Disorders of autonomic nervous system
G90.0 Idiopathic peripheral autonomic neuropathy
G90.01 Carotid sinus syncope
G90.09 Other idiopathic peripheral autonomic neuropathy
G90.1 Familial dysautonomia [Riley-Day]
G90.2 Horner's syndrome
G90.3 Multi-system degeneration of the autonomic nervous system
G90.4 Autonomic dysreflexia
G90.5 Complex regional pain syndrome I (CRPS I)
G90.50 Complex regional pain syndrome I, unspecified
G90.51 Complex regional pain syndrome I of upper limb
G90.511 Complex regional pain syndrome I of right upper limb
G90.512 Complex regional pain syndrome I of left upper limb
G90.513 …… bilateral
G90.519 Complex regional pain syndrome I of unspecified upper limb
G90.52 Complex regional pain syndrome I of lower limb

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.