2021 ICD-10-CM Code S04.042A

Injury of visual cortex, left side, initial encounter

Version 2021
Billable Code
7th Character Code
Initial Code

Valid for Submission

S04.042A is a billable diagnosis code used to specify a medical diagnosis of injury of visual cortex, left side, initial encounter. The code S04.042A is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.

S04.042A is an initial encounter code, includes a 7th character and should be used while the patient is receiving active treatment for a condition like injury of visual cortex left side. According to ICD-10-CM Guidelines an "initial encounter" doesn't necessarily means "initial visit". The 7th character should be used when the patient is undergoing active treatment regardless if new or different providers saw the patient over the course of a treatment. The appropriate 7th character codes should also be used even if the patient delayed seeking treatment for a condition.

ICD-10:S04.042A
Short Description:Injury of visual cortex, left side, initial encounter
Long Description:Injury of visual cortex, left side, initial encounter

Code Classification

Convert S04.042A to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code S04.042A its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.

Information for Patients


Traumatic Brain Injury

Also called: Acquired brain injury, TBI

Traumatic brain injury (TBI) happens when a bump, blow, jolt, or other head injury causes damage to the brain. Every year, millions of people in the U.S. suffer brain injuries. More than half are bad enough that people must go to the hospital. The worst injuries can lead to permanent brain damage or death. Half of all TBIs are from motor vehicle accidents. Military personnel in combat zones are also at risk.

Symptoms of a TBI may not appear until days or weeks following the injury. A concussion is the mildest type. It can cause a headache or neck pain, nausea, ringing in the ears, dizziness, and tiredness. People with a moderate or severe TBI may have those, plus other symptoms:

Health care professionals use a neurological exam and imaging tests to assess TBI. Serious traumatic brain injuries need emergency treatment. Treatment and outcome depend on how severe the injury is. TBI can cause a wide range of changes affecting thinking, sensation, language, or emotions. TBI can be associated with post-traumatic stress disorder. People with severe injuries usually need rehabilitation.

NIH: National Institute of Neurological Disorders and Stroke


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Vision Impairment and Blindness

Also called: Low vision

If you have low vision, eyeglasses, contact lenses, medicine, or surgery may not help. Activities like reading, shopping, cooking, writing, and watching TV may be hard to do. The leading causes of low vision and blindness in the United States are age-related eye diseases: macular degeneration, cataract and glaucoma. Other eye disorders, eye injuries, and birth defects can also cause vision loss.

Whatever the cause, lost vision cannot be restored. It can, however, be managed. A loss of vision means that you may have to reorganize your life and learn new ways of doing things. If you have some vision, visual aids such as special glasses and large print books can make life easier. There are also devices to help those with no vision, like text-reading software and braille books.

The sooner vision loss or eye disease is found and treated, the greater your chances of keeping your remaining vision. You should have regular comprehensive eye exams by an eye care professional.

NIH: National Eye Institute


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Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)