Retinitis Pigmentosa

History Taking

​​Chief Complaint:

• Gradual, progressive vision loss

• Difficulty in night vision (Nyctalopia)

History of Presenting Complaint:

• Progressive difficulty seeing in dim light or at night

• Loss of peripheral vision, tunnel vision

• Decreased visual acuity

• Frequent changes in eye glass prescription due to refractive changes

• Occasional complaints of photopsia (flashes of light)

• Symptoms may have been present for several years before seeking medical advice

• Often symptoms are first noticed in childhood or adolescence, but can manifest later in life

System Review:

• May exhibit findings related to associated systemic conditions in syndromic cases (e.g. hearing loss in Usher syndrome, obesity or renal abnormalities in Bardet-Biedl syndrome)

Past Medical History:

• May have a history of associated conditions in syndromic cases of retinitis pigmentosa (like Usher syndrome or Bardet-Biedl syndrome)

Past Surgical History:

• May have a history of cataract surgery (cataract is a common complication in these patients)

Drug History:

• May be on medication for associated conditions if retinitis pigmentosa is part of a syndrome

Family History:

• Family history of retinitis pigmentosa or related inherited eye disorders

• Siblings or parents with similar symptoms

• Possible consanguinity in parents

Personal History:

• Adaptations to vision loss, such as use of mobility aids, reliance on others for tasks requiring good vision

Social History:

• Progressive limitations in daily activities, such as driving, especially at night

• Difficulty in job performance, particularly if work involves fine visual tasks or night work

• Potential need for occupational adjustment or retirement on medical grounds

• Possible social isolation or psychological distress due to progressive vision loss

Physical Examination

General Examination:

• Evidence of visual aids such as guide dogs or canes

• Signs of adaptations to poor vision like careful movement around unfamiliar areas

Examination of the Hands/Arms:

• Normal appearance and function, unless associated with a syndromic form of retinitis pigmentosa

Examination of the Face:

• Eyes: Signs of recent eye surgery (such as cataract surgery)

• Eyes: Pale, waxy optic disc on fundoscopy

• Eyes: Bone spicule pigmentation in the mid-peripheral retina on fundoscopy

• Eyes: Narrowing of the retinal vessels on fundoscopy

• Eyes: Absence of red reflex

Neurological Examination:

• Normal cranial nerve examination apart from optic nerve abnormalities

• Normal motor, sensory and reflex examination unless retinitis pigmentosa is part of a neurological syndrome

Additional Examination if Relevant:

• Audiometry if suspected Usher syndrome

• Assessment of gait and balance, particularly in unfamiliar or poorly lit surroundings

• Examination of other siblings or parents if available and consent given, for similar retinal signs

Investigations

Laboratory Investigations:

• Full Blood Count: to rule out other systemic causes of visual loss

• Serum Electrolytes: to check for any imbalances, which can sometimes occur in syndromic forms of retinitis pigmentosa

• Genetic Testing: to identify mutations associated with retinitis pigmentosa and to aid in diagnosis

Imaging:

• Optical Coherence Tomography (OCT): provides detailed images of the retina, allowing for assessment of retinal thickness and structure, which may show thinning of the retinal layers

• Fundus Fluorescein Angiography (FFA): can highlight changes in the retinal vasculature and pigment epithelium, common in retinitis pigmentosa

Invasive:

• Electroretinogram (ERG): measures the electrical responses of various cell types in the retina, including the photoreceptors (rods and cones), inner retinal cells (bipolar and amacrine cells), and the ganglion cells. Diminished or absent responses can confirm diagnosis of retinitis pigmentosa

Other Tests:

• Visual Field Testing: to determine the extent of peripheral vision loss

• Visual Acuity Test: to assess the extent of central vision loss

• Dark Adaptation Test: measures sensitivity to light and can identify problems with night vision, a key symptom of retinitis pigmentosa

• Color Vision Testing: to assess the function of the cone cells in the retina

• Audiometry: if Usher syndrome is suspected, which is a condition that causes both hearing loss and vision loss.

Management

General Management:

• Genetic counselling: to understand the implications for the patient and their family

• Patient education: about the nature and course of the disease

• Regular follow-ups: for monitoring disease progression and adjusting management accordingly

• Low vision aids: such as magnifying glasses, and night vision scopes for improved quality of life

• Occupational therapy: to help with adapting to changes in vision

• Psychological support: to manage potential mental health issues related to chronic vision loss

Medical Management:

• Vitamin A supplementation: some studies suggest it may slow the progression of the disease

• Lutein supplementation: may help preserve central vision, although more research is needed

• Omega-3 fatty acids: may slow disease progression

• Oral valproic acid: still experimental, but some evidence suggests it may slow the progression of the disease

• Regular ophthalmological evaluations: to detect and manage complications like cataracts and macular oedema

Surgical Management:

• Cataract surgery: to manage cataracts, a common complication of retinitis pigmentosa

• Implantable miniature telescope: can improve central vision in late-stage disease

• Retinal implants: experimental treatment for severe vision loss

Other Management:

• Physical activity and healthy diet: general measures to maintain overall health

• Support groups: to help cope with the emotional aspects of the disease

• Use of sunglasses: to protect the eyes from sun damage, as the eyes can be more sensitive to light

• Research trials: participation in ongoing research to access experimental therapies