Development of a Device to Measure Dark Adaptation

NCT02090751 | Completed

• 1 other identifier: II-LB-0712-20001
• Study Type: observational
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

Age Related Macular Disease (AMD) is easily the leading cause of blindness in older people in developed countries. It affects between 30 and 50 million individuals worldwide, with around 30% of the over 65's showing early signs of the disease. Severe AMD has a devastating impact on the quality of life; it causes extensive visual impairment, making reading difficult and driving impossible. Patients lose their independence and become a major burden on public health systems. Present treatment options are limited. Many new therapies are under development and all will need evaluation using a test with high specificity and sensitivity for early AMD. The present application will develop such an instrument. The prototype was funded by a previous i4i FS (feasibility study ll-FS-0110-14036). The new device measures sensitivity to a dim flickering light using the same principle as an established european conformity marked (CE marked) instrument. The original method involved lights of different wavelengths and higher intensities. The instrument in this study assesses night vision, which is selectively damaged in early stage AMD. In low lighting, the investigators vision depends on specialized rod photoreceptors. Cone photoreceptors, which provide daytime vision, remain normal in the early stages of the disease. By the time patients complain of reduced (cone-based) visual acuity, they will have had the disease for many years and lost many thousands of photoreceptors.

Conditions

Macular Degeneration; Age-Related Macular Degeneration

Keywords

Retinal Rod Photoreceptor Cells; Dark Adaptation

Outcome Measures

Primary Outcomes (1)

• The rate of recovery of the rod phase S2

  Dark adaptation will be measured in 40 participants; 20 healthy and 20 with early macular disease. This index of retinal health will be analysed for its sensitivity and specificity for the identification participants with macular disease.

  At participant visit only

Secondary Outcomes (2)

• Lifestyle questionnaire

  At participant visit only.

• Participant Experience Questionnaire

  Within one month of participant visit.

Study Arms (2)

No Maculopathy

Aged 50 to 80 with no macular disease

Early Maculopathy

Aged 50 to 80 with early AREDS defined 2,3 age related maculopathy

Eligibility Criteria

• Age: 50 Years - 80 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Participants will be recruited from a the greater manchester area by a call for volunteers, through the local newspaper, a university email list and through the Hale Barns Macular Disease Association

You may qualify if:

• They understand their rights as a research Participant and are willing and able to sign a Statement of Informed Consent.
• They are over 50 years and less than 80 years of age.
• They are willing and able to perform the experimental task required.
• They are not a current participant in other studies. Lifestyle factors
• Diet that includes animal and/or vegetable fats. Health factors
• Good ocular health, the following will be admitted Pseudophakia, aphakic with good VA (better than 6/12), AMD with AREDS category 1,2,or 3.
• Good systemic health, the following may be admitted Hypertension Thyroid disease Arthritis Depression
• Medication, that is not hepatotoxic or retinotoxic directly or by treating a disease that is may be admitted. Use British National Formulary (BNF) to check if unsure.

You may not qualify if:

• Unlikely to be available, willing, and able to attend
• Unable to give consent.
• Current participant in other studies.
• Subject to any condition that may adversely affect fat intake (proxy for Vit A) or retinal function.
• Lifestyle factors
• Diet that excludes animal and/or vegetable fats.
• Health factors
• Ocular Any active disease, e.g. · Glaucoma, Cataract if VA worse than 6/12 · Diabetic Retinopathy · Retinal detachment · Uveitis Treatments · Laser Sx. to cornea, capsule or retina · Recent cataract extraction within 12 weeks · Drops
• Systemic Diabetes Liver disease, Hepatitis: Past or present Digestive disorders, e.g. Crohns, irritable bowel syndrome (IBS), lactose intolerance Bowel surgery, stomach staple, ileostomy, colostomy Kidney disorder (elevated iron) Chronic alcoholism or drug abuse
• Medication, hepatotoxic or retinotoxic directly or by treating a disease that is. If unsure use BNF and seek advice of ophthalmologist/study leader. Examples include:
• Interferon alpha
• Vitamin A derivatives (Chronic eczema)
• Amiodarone (Heart disease)
• Chloroquine/Hydrochloroquine (Plaquenil) (Rheumatoid Arthritis/ Malaria)
• Tamoxifen (Breast Cancer)

Sponsors & Collaborators

• University of Manchester: lead

Study Sites (1)

University of Manchester

Manchester, Greater Manchester, M13 9PL, United Kingdom

Location

MeSH Terms

Conditions

Macular Degeneration

Condition Hierarchy (Ancestors)

Retinal Degeneration; Retinal Diseases; Eye Diseases

Study Officials

• Ian J Murray, PhD

  University of Manchester

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: NIHR i4i Researcher

Study Record Dates

• First Submitted: March 12, 2014
• First Posted: March 18, 2014
• Study Start: July 1, 2014
• Primary Completion: February 1, 2015
• Study Completion: April 1, 2015
• Last Updated: July 6, 2016

Record last verified: 2016-07

Locations

GB (1)