ABSTRACT
PURPOSE: A pilot investigation to transfer the established corneal collagen crosslinking (CXL) procedure in European eyes into clinically affected African eyes and to optimize the treatment by adapting the riboflavin composition. MATERIALS AND METHODS: CXL was performed in 15 eyes (11 patients) with advanced stages of keratoconus in the Eye Clinic of Bafoussam in the West Region of Cameroon. The following six riboflavin compositions with different portions of active swelling additives were applied: Solution 1 (0.5% methylhydroxypropylcellulose [MHPC]), solution 2 (1.0% MHPC), solution 3 (1.7% MHPC), solution 4 (5% dextran), solution 5 (10% dextran) and solution 6 (no active swelling ingredient). The central corneal thickness (CCT) was measured by ultrasound pachymetry before and after de-epithelialization and at least every 10 min during CXL. RESULTS: THE APPLICATION OF THE RIBOFLAVIN SOLUTIONS RESULTED IN THE FOLLOWING MEAN FINAL CCT VALUES: 172 ± 15% using solution 1 (60 min/n = 5); 183 ± 8% using solution 2 (60 min/n = 5); 170% using solution 3 (60 min/n = 1); 80% using solution 4 (45 min/n = 1); 99% using solution 5 (45 min/n = 1) and 150 ± 13% using solution 6 (50 min/n = 2). CONCLUSIONS: The combination of riboflavin compositions with swelling and stabilizing effects on the corneal stroma seems necessary in African eyes with advanced keratoconus. Further studies are required to confirm these primary results.
Subject(s)
Black People , Collagen/metabolism , Corneal Stroma/pathology , Cross-Linking Reagents/therapeutic use , Keratoconus/drug therapy , Photosensitizing Agents/therapeutic use , Riboflavin/therapeutic use , Adolescent , Adult , Child , Corneal Pachymetry , Corneal Stroma/metabolism , Cross-Linking Reagents/chemistry , Female , Humans , Hypromellose Derivatives , Keratoconus/ethnology , Keratoconus/metabolism , Male , Methylcellulose/analogs & derivatives , Methylcellulose/therapeutic use , Photochemotherapy/methods , Photosensitizing Agents/chemistry , Pilot Projects , Riboflavin/chemistry , Ultraviolet Rays , Young AdultABSTRACT
PURPOSE: To quantify glaucoma-related parameters in a rural African region. MATERIAL AND METHOD: In a population-based investigation, 635 persons in six villages underwent slit-lamp examination including investigation of the optic nerve head with a 90D lens and Goldmann applanation tonometry. The mean age of the persons was 49.4 +/- 19 years, minimum 5, maximum 90, median 52 years. The inferior, superior, nasal and temporal margin width of the optic nerve head (ONH) were estimated as fractions of the total disk diameter, thus allowing the evaluation of the horizontal and vertical cup-disk ratio (CDR), the ratio of the elliptical cup area to the total disk area (area CDR), and violations of the ISNT rule (Inferior>or=Superior>or=Nasal>or=Temporal ONH rim). RESULTS: Area CDR significantly increased with age, on average from 0.1 in the youngest to 0.47 in the oldest person, corresponding to an increase of linear CDR from 0.32 to 0.68. The total fraction of eyes exceeding an area CDR of 0.5 (i.e. linear 0.7) was 13.4%. In addition, the intraocular pressure (IOP) increased on average from 14 mmHg in the youngest to 20 mmHg in the oldest persons, but nevertheless many high CDR values were found in eyes with normal to moderately elevated IOP. Violations of the ISNT rule were found in approximately 25% of the eyes. Application of a combination of glaucoma criteria as commonly used in literature resulted in a total prevalence of 18.7% of the screened persons, corresponding to a prevalence of 8.2% after age correction for the--on average--very young Cameroonian population. CONCLUSION: Compared to Europe, glaucoma prevalence appears to be nearly an order of magnitude higher in this rural African population.
