Cone Rescue in Retinitis Pigmentosa by the Treatment of Lycium Barbarum

The study was a randomized controlled trial with a double-masked, placebo-controlled design. All the subjects were randomly allocated into either LB (treatment) group or placebo (control) group.

All the eligible subjects had the eye examination, including VA using the Early Treatment of Diabetic Retinopathy Study (ETDRS) chart, refractions, tonometry, external and internal ocular health assessments, and fundus photo-documentation. Three additional tests were conducted to investigate the functional and structural changes in the RP patients, including Ganzfeld Electroretinogram, Humphrey Visual Field Analyser (Zeiss, Dublin, USA) and Spectral-domain Optical Coherent Tomography (SD-OCT) (Heidelberg Engineering, USA).

Inclusion criteria

Ocular conditions:

• Retinitis pigmentosa;
• best corrected VA LogMAR 0.20 or better;
• Humphrey Visual Field Analysis (HVFA) 30-2 total mean defect > or = 250 Decibel;
• Intra-ocular pressure (IOP) <21 mmHg;
• van Herrick ratio < or = 0.5;
• no other ocular diseases

Dietary conditions:

• Fruit and vegetable intake <10 servings/day;
• spinach or kale intake < or = serving/day;
• dietary lutein intake < or = 5.4mg/day;
• no intake of cod liver oil or omega-3 capsules;
• dietary Lycium barbarum intake < or =10 fruits/week;
• supplement intake < or = 5000 IU/day of Vit. A and < or = 30 IU/day of Vit. E;
• alcoholic consumption < or = 3 beverages/day

Exclusion criteria

• BMI > 40;
• intake of any anticoagulants (especially Warfarin),
• pregnant or planning to be pregnant;
• smoking;
• other clinically significant systemic diseases, eg. diabetes, liver disease and heart disease