2021 ICD-10-CM Code G91.1

Obstructive hydrocephalus

Version 2021

Valid for Submission

G91.1 is a billable diagnosis code used to specify a medical diagnosis of obstructive hydrocephalus. The code G91.1 is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.

The ICD-10-CM code G91.1 might also be used to specify conditions or terms like acquired obstructive hydrocephalus, hydrocephalus associated with late onset aqueduct stenosis, obstructive hydrocephalus, postmeningitic hydrocephalus, postmeningitic obstructive hydrocephalus , post-traumatic hydrocephalus, etc.

ICD-10:G91.1
Short Description:Obstructive hydrocephalus
Long Description:Obstructive hydrocephalus

Code Classification

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code G91.1 are found in the index:

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Clinical Information

Convert G91.1 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code G91.1 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


Hydrocephalus

Also called: Water on the brain

Hydrocephalus is the buildup of too much cerebrospinal fluid in the brain. Normally, this fluid cushions your brain. When you have too much, though, it puts harmful pressure on your brain.

Hydrocephalus can be congenital, or present at birth. Causes include genetic problems and problems with how the fetus develops. An unusually large head is the main sign of congenital hydrocephalus.

Hydrocephalus can also happen after birth. This is called acquired hydrocephalus. It can occur at any age. Causes can include head injuries, strokes, infections, tumors, and bleeding in the brain. Symptoms include

Hydrocephalus can permanently damage the brain, causing problems with physical and mental development. If untreated, it is usually fatal. With treatment, many people lead normal lives with few limitations. Treatment usually involves surgery to insert a shunt. A shunt is a flexible but sturdy plastic tube. The shunt moves the cerebrospinal fluid to another area of the body where it can be absorbed. Medicine and rehabilitation therapy can also help.

NIH: National Institute of Neurological Disorders and Stroke


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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)