What is the Difference Between Glaucoma and Retinitis Pigmentosa

Glaucoma and retinitis pigmentosa are two eye conditions that affect peripheral vision. Peripheral vision, also known as indirect vision, occurs outside the point of fixation. When there is a problem with the peripheral vision, it takes more effort to see things around people.

The key difference between glaucoma and retinitis pigmentosa is the organs affected. Glaucoma is an eye condition that damages the optic nerve due to increased pressure within the eye, while retinitis pigmentosa is an eye condition that affects the retina due to inherited gene mutations.

ONTENTS

1. Overview and Key Difference
2. What is Glaucoma 
3. What is Retinitis Pigmentosa
4. Similarities – Glaucoma and Retinitis Pigmentosa
5. Glaucoma vs Retinitis Pigmentosa in Tabular Form
6. Summary – Glaucoma vs Retinitis Pigmentosa
7. FAQ – Glaucoma and Retinitis Pigmentosa 

What is Glaucoma?

Glaucoma is a disease affecting the optic nerve. The eye constantly makes a fluid called aqueous humor. This fluid also drains out from the eye through the area called drainage angle. But if the drainage angle does not work properly, the fluid accumulates in the eye. This raises the pressure inside the eye, damaging the optic nerve. Scientists have also identified gene mutations can lead to glaucoma. The general symptoms of glaucoma are seeing halos around lights, vision loss, blurred vision with exercise or loss of side vision, redness in the eye, upset stomach or vomiting, eye pain, and severe headache.

Figure 01: Comparing Normal Vision with Glaucoma

Glaucoma can be diagnosed through dialed eye examination, gonioscopy, optical coherence tomography (OCT), ocular pressure test, pachymetry, slit lamp test, visual acuity test, and visual field test. Furthermore, treatment options for glaucoma are prescription medications such as glaucoma eyedrops, beta-blocker or carbonic anhydrase inhibitors, laser surgery, microsurgery, and minimally invasive glaucoma surgeries.

What is Retinitis Pigmentosa?

Retinitis pigmentosa is a disease that affects the retina of the eye. The retina is an important layer at the back of the eye that converts light into electrical signals, which allows the brain to identify visual images. Retinitis pigmentosa is caused by mutations in certain genes controlling the cells that make up the retina. The signs and symptoms of retinitis pigmentosa include problems with night vision, problems seeing under dim light, blind spots in side vision, having a sensation of twinkling, tunnel vision, being sensitive to bright light, losing the ability to see color, and having very low vision.

Figure 02: Retinitis Pigmentosa

Retinitis pigmentosa can be diagnosed through dilated eye examination, visual field test, electroretinography (ERT), optical coherence tomography (OCT), and fundus autofluorescence test. Furthermore, treatment options for retinitis pigmentosa include using low vision aids and assistive devices, using sunglasses and other methods to avoid exposure to excess light, managing associated conditions, such as cystoid macular edema (CME), and managing cataracts with surgery.

Similarities Between Glaucoma and Retinitis Pigmentosa

1. Glaucoma and retinitis pigmentosa are two eye conditions that affect peripheral vision.
2. Both conditions can be triggered by inherited gene mutations.
3. They can lead to low vision or vision loss.
4. Both conditions can be diagnosed through eye examination.
5. They can be treated with medications and surgeries.

Difference Between Glaucoma and Retinitis Pigmentosa

Definition

1. Glaucoma is a disease that affects the optic nerve of the eye.
2. Retinitis pigmentosa is a disease that affects the retina of the eye.

Causes

1. Glaucoma is caused by increased pressure within the eye, triggered by certain gene mutations.
2. Retinitis pigmentosa can be caused by mutations in certain genes control the cells that make up the retina.

Symptoms

1. Symptoms of glaucoma include blurred narrow vision, severe pain in the eye, seeing halos or “rainbows” around lights, nausea, vomiting, and headache.
2. Symptoms of retinitis pigmentosa include reduced vision in poor lighting, reduced ability to see objects in the side vision, gradual narrowing of the total area of good vision, stumbling or tripping over objects in the periphery, blurriness, and missing vision.

Diagnosis

1. Glaucoma can be diagnosed by visual acuity test, pupil dilation, visual field test, tonometry, optic nerve imaging, gonioscopy, and pachymetry.
2. Retinitis pigmentosa can be diagnosed by chart test, ophthalmoscopy, refraction test, retinal exam, electroretinography, visual field measurement, and genetic testing.

Treatment

1. Glaucoma can be treated by medicines that cause the eye to make less fluid, a surgery implanting a shunt to help drain the fluid, laser surgery, and eye surgery.
2. Retinitis pigmentosa can be treated by gene therapy for only one gene that causes retinitis pigmentosa called the RPE65 gene, surgery for cataracts, medications to reduce macular edema, avoiding taking vitamin E supplementation in excess of 30 IU per day, and protecting the retinas from bright sunlight, wearing sunglasses with a UV filter.

The following table summarizes the difference between glaucoma and retinitis pigmentosa.

Summary – Glaucoma vs Retinitis Pigmentosa

Peripheral vision is the ability to see things where people are not directly looking at something. Some of the most common eye diseases that cause peripheral vision are glaucoma, retinitis pigmentosa, and diabetes-related retinopathy. Therefore, glaucoma and retinitis pigmentosa are two eye conditions that affect the peripheral vision. People with glaucoma have optic nerve damage from fluid buildup in their eyes, while people with retinitis pigmentosa have retina damage from inherited gene mutations in their eyes. This is the summary of the difference between glaucoma and retinitis pigmentosa.

FAQ: Glaucoma and Retinitis Pigmentosa

1. What is the cause of glaucoma?

• Glaucoma is a chronic, progressive eye disease caused by damage to the optic nerve due to increased pressure within the eye by fluid buildup. It leads to visual field loss.

2. At what age do people get glaucoma?

• Glaucoma normally can occur at any age, but it is more common in older adults. It is one of the leading causes of blindness for people over the age of 60. The other risk factors include Hispanic/Latino, African American and over age 40. This condition is progressive, and one may not notice a change in vision until the condition is in its later stages.

3. Can glaucoma be repaired?

• There are several different treatments for glaucoma, including prescription medications such as eye drops, laser treatment, and surgery. These treatments can help stop the vision getting any worse.

4. What happens if people have retinitis pigmentosa?

• Retinitis pigmentosa is caused by inherited gene mutations (around 100). It leads to poor vision in dim light and, in most cases, progresses to a constriction in the visual field that causes tunnel vision and a decline in eyesight even in good lighting.

5. Can retinitis pigmentosa be corrected?

• There is no cure for retinitis pigmentosa. But vision aids and rehabilitation programs can help people with retinitis pigmentosa make the most of their vision. The treatment options for retinitis pigmentosa may include gene therapy, surgery for cataract, medications to manage macular edema, low vision aids and assistive devices and avoiding exposure to too much light by wearing sunglasses.

Reference:

1. “Glaucoma: Symptoms, Causes, Types & Treatment.” Cleveland Clinic, .
2. “Retinitis Pigmentosa.” Johns Hopkins Medicine.

Image Courtesy:

1. “Depiction of vision for a Glaucoma patient” By Myupchar.com (CC BY-SA 4.0) via Commons Wikimedia
2. “Fundus of patient with retinitis pigmentosa, early stage” By Christian Hamel – Retinitis pigmentosa by Christian Hamel (CC BY 2.0) via Commons Wikimedia

Related posts:

Difference Between Scleritis and Episcleritis         Difference Between Blepharochalasis and Dermatochalasis Difference Between Ptosis and Blepharoplasty Difference Between Blepharitis and Stye Difference Between Internal and External Ophthalmoplegia