Disease name: Primary Open Angle Glaucoma

ICD-10 Disease Code: H40.11 - Primary Open Angle Glaucoma

ICD-10 Disease Group: H40 - Glaucoma

Open-angle glaucoma (OAG) is the most common type of glaucoma. Glaucoma is a group of eye conditions that can damage the optic nerve, which is responsible for transmitting images to the brain. Commonly, such optic nerve damage is caused by increased pressure in the eye known as intraocular pressure. In OAG, the increase in pressure is often small and progresses slowly over time. The exact cause of the pressure increase in OAG remains unknown and usually cannot be felt by patients. The resulting damage to the optic nerve causes blind spots in the vision.

OAG tends to run in families, with an increased risk for individuals who have a parent or grandparent with the condition. Additionally, people of African descent are at a higher risk of developing the disease. Juvenile or early onset OAG is a rare type of primary open-angle glaucoma (POAG) that is caused by genetic variations. The MYOC gene, a gene heavily associated with early onset POAG encodes a protein called myocilin which is found in trabecular meshwork and the ciliary body, a structure in the eye that regulates the intraocular pressure.

Approximately 10-33% of individuals with early onset POAG harbour variants in the MYOC gene. These variants can occur from genetic inheritance but also from external sources such as viral infection. MYOC gene variants have also been detected in some individuals with primary congenital glaucoma. 

Mutations in the TMCO1 gene also appear to be associated with POAG in certain populations but not in others. Specifically how these genetic variations affect OAG remains unknown.

Early onset Open Angle Glaucoma (OAG) affects about 1 in 50,000 individuals worldwide. Primary OAG is most commonly diagnosed after the age of 40, affecting about 1-2% of the population worldwide.

Most individuals with OAG have no symptoms. Once vision loss becomes apparent, the damage is already severe. A slow loss of peripheral vision is the main type of vision loss. Advanced glaucoma can lead to complete blindness.

There is currently no cure for OAG, all though with proper management vision can be rescued. Treatment depends on the type of glaucoma and primarily involves attempting to reduce eye pressure. 

The majority of individuals with OAG can be treated with eye drops, and there are a variety of different types of eye drops available with more than one type commonly being required. Most eye drops prescribed in recent years cause fewer side effects in comparison to those used in the past. 

Some oral treatments are also available to lower the pressure in the eye.

• https://www.icd10data.com/
• https://www.orpha.net/consor/cgi-bin/index.php
• https://rarediseases.org/
• https://medlineplus.gov/genetics/
• https://www.cdc.gov/

Tags

Primary Open Angle Glaucoma