Retinitis Pigmentosa

Retinitis pigmentosa is an inherited and progressive retinal disease but can also be present alongside specific systemic diseases, such as Alport syndrome, Kearn-Sayre syndrome, Refsum disease, and Usher Syndrome.^{2, 3, 4} Retinitis pigmentosa causes degeneration of the rods and cones in the retina.¹⁰ Retinitis pigmentosa is characterized by narrowing of the blood vessels on the retina, dark “bone-spicule” markings on the retina, and optic nerve pallor/whitening.⁵

Retinitis pigmentosa can cause decreased vision at night, loss of peripheral vision, decreased color vision, glare, and loss of central vision (usually in later stages).^{2, 8}

Retinitis pigmentosa is an inherited retina condition, which can be inherited by autosomal dominant, autosomal recessive, or x-linked recessive genes. Retinitis pigmentosa can also occur without inheritance from parents.³

Genetic testing: available for several gene mutations that can cause RP²

Ophthalmic examination: an eye care practitioner can note characteristics of retinitis pigmentosa by viewing the retina and optic nerve in the back of the eye

Humphrey Visual Field (HVF): side vision test to determine if side vision loss is characteristic of RP

Ocular coherence tomography (OCT): ultrasound through the central vision area, the macula, as RP can cause cystoid macular edema

Electroretinogram (ERG): tests the activity of the photoreceptors of the retina in the back of the eye¹

There is no treatment at this time for retinitis pigmentosa, but management can be implemented to improve quality of life for patients with this condition, explained below.

Retinitis pigmentosa is a progressive disease, therefore eye exams as recommended by a patient’s eye care provider is important to assess progression of the condition. Glasses with amber filters can assist with discomfort associated with bright lights. Sunglasses are important for UV protection to protect the retina.^{2, 8} The Argus II device is an FDA approved camera that is mounted on a patient’s glasses and takes photos of the outside world and projects these images to the retina.⁹ Other low vision devices, like magnifiers, reverse telescopes, and glasses that assist with side vision are options for patients with retinitis pigmentosa to assist to daily activities.¹⁰ Counseling and support groups for patients with retinitis pigmentosa are an excellent option for career and life support, as this disease is progressive and vision decreases over time.

Usher Syndrome

Usher syndrome is a rare genetic and progressive condition associated with retinitis pigmentosa. This syndrome also causes deafness and can cause balance issues.⁴ Usher syndrome is an autosomal recessive condition, whereas the gene mutation is inherited by both parents. If both parents are “carriers” of this gene mutation, there is a 25% change that their child will develop Usher syndrome.⁶

There are three types of Usher syndrome: Usher Syndrome Type 1 (USH1), Usher Syndrome Type 2 (USH2), and Usher Syndrome Type 3 (USH3).

Usher Syndrome Type 1 (USH1): severe non-progressive hearing loss, balance issues, vision issues in early adolescence^{3, 7}

Usher Syndrome Type 2 (USH2): moderate-severe progressive hearing loss, vision issues post-adolescence

Usher Syndrome Type 3 (USH3): mild hearing loss, balance issues may be present, vision issues in adulthood⁷

Usher syndrome can be diagnosed with all ocular methods used to diagnose retinitis pigmentosa, as well as, a hearing evaluation and genetic testing to determine which type of Usher Syndrome the patient has.⁶

Treatment for Usher syndrome includes treatment of hearing loss (cochlear implants, hearing aids, auditory training), vision loss (low vision treatment), balance issues (orientation and mobility training), and counseling.⁶

1. https://www.aao.org/eye-health/diseases/what-is-retinitis-pigmentosa
2. https://www.columbiaeye.org/content/retinitis-pigmentosa
3. https://rarediseases.org/rare-diseases/retinitis-pigmentosa/
4. https://rarediseases.org/rare-diseases/usher-syndrome/
5. https://eyewiki.aao.org/Retinitis_Pigmentosa#Physical_examination_and_signs
6. https://www.hopkinsmedicine.org/health/conditions-and-diseases/usher-syndrome
7. https://www.fightingblindness.org/diseases/usher-syndrome
8. https://www.cedars-sinai.org/health-library/diseases-and-conditions/r/retinitis-pigmentosa.html
9. https://www.asrs.org/patients/retinal-diseases/8/retinitis-pigmentosa-and-retinal-prosthesis
10. https://www.optometrists.org/general-practice-optometry/guide-to-low-vision/retinitis-pigmentosa-and-low-vision/