Risk of major myopia-associated non-communicable ocular health disorders in Ghana.

OBJECTIVE: To assess the differential association of myopia with major non-communicable ocular diseases in an African clinical cohort. METHODS: A five-year hospital-based retrospective study of myopia cases. Patients' folders, Optical Coherence Tomography scans, and fundus photographs were reviewed for the abstraction of relevant data. Only records that employed recognized standards and classification systems for diagnosing and staging the various ocular conditions were included. Demographic characteristics, non-cycloplegic objective refractive findings, and non-communicable eye diseases were retrieved from the records. Myopia-associated risk factors were then determined using logistic regression and correlation. RESULTS: Some 16018 patients (32027 eyes) met the inclusion criteria for at least one eye comprising 50.8% males (n = 8137) and 49.2% females (n = 7881). The mean age of the patients was 43.14 ± 17.88 years (range: 2-98 years). The mean spherical equivalent± Standard deviation for myopia was -2.30±3.23 DS (range: -0.50 to -25DS). Binary logistic regression analysis showed that myopic eyes had a higher odd of AC (OR, 0.53; 95% CI, 0.50-0.57), POAG (OR, 6.0; 95% CI, 5.26-6.82), DR (OR, 10.70; 95% CI, 3.91-29.27) and cataracts (OR, 20; 95% CI, 15.32-26.20) but not dry eye (OR, 0.74, 95% CI, 0.68-0.81), macular degeneration and pterygium (OR, 0.36; 95% CI, 0.32-0.40). CONCLUSION: Africans with myopia are more at risk of developing allergic conjunctivitis, cataracts, POAG, and DR but not for dry eye, macular degeneration, and pterygium.

Efficacy of intravitreal bevacizumab on diabetic macular oedema in an African population.

PURPOSE: To evaluate the short-term effect of intravitreal bevacizumab (avastin) injection on visual outcomes of patients with diabetic macular oedema. METHODS: A retrospective cross-sectional study was conducted to evaluate 39 eyes of thirty-nine patients (mean age ± SD: 61.4 ± 15.0 years) that received intravitreal bevacizumab injection (1.25 mg in 0.05 ml) as treatment for diabetic macular oedema between January 2014 and July 2019 in Ghana. Data on visual acuity and central macular thickness before treatment and 6 weeks post-treatment were collected and analysed using paired t-test. Ordinary least squares linear regression analysis was also conducted to determine the relationship between improvement in visual acuity and central macular thickness after treatment and other predictor variables. RESULTS: The mean ± SD visual acuity (LogMAR-equivalent of Snellen) of patients with diabetic macular oedema significantly improved from 0.84 ± 0.58 LogMAR before treatment to 0.69 ± 0.58 LogMAR at 6 weeks post-treatment (mean difference: 0.15 ± 0.32 LogMAR; 95% CI: 0.04 to 0.25; p = 0.01). Mean macular thickness ± SD on the other hand, reduced significantly (p < 0.001) from 316.54 ± 75.35 µm before treatment to 275.54 ± 57.43 µm after treatment. While age and worse pre-treatment visual acuity predicted improvement in visual acuity after treatment, a higher central macular thickness before treatment predicted an improvement in central macular thickness after intravitreal bevacizumab injection. CONCLUSION: Treatment with intravitreal bevacizumab injection produces short-term improvement in vision and reduction in central macular thickness in African patients with diabetic macular oedema.

Comparison of anterior segment parameters in myopia with and without primary open-angle glaucoma.

PURPOSE: To compare anterior segment parameters between myopes with and without primary open-angle glaucoma using Pentacam scheimpflug tomography. METHODS: This was a single-center retrospective cross-sectional study. Records of patients examined with a Pentacam scheimpflug tomographer (Wavelight-Allegro Oculyzer, GmbH, Erlangen, Germany) were reviewed. Variables studied were recorded from the topographic map and included anterior chamber angle, anterior chamber volume, anterior chamber depth, keratometric readings, and corneal thickness. A general linear model for age-and spherical equivalent refraction-adjusted intergroup comparisons of the anterior segment parameters was conducted. RESULTS: The study included myopes previously diagnosed with primary open-angle glaucoma (POAG) [Mild defect, n = 81; Moderate-severe defect, n = 50] and non-glaucomatous myopes (n = 247). The results revealed a smaller anterior chamber angle, shallower anterior chamber depth, and flatter cornea curvature in the mildly glaucomatous group compared to the non-glaucomatous group (p < 0.05). Smaller anterior chamber angle, shallower anterior chamber depth, and thinner cornea thickness were also observed in the moderate-severely glaucomatous group compared to the non-glaucomatous group (p < 0.05). CONCLUSION: Glaucomatous damage in myopic patients with POAG was associated with comparatively small anterior chamber angle, shallow anterior chamber depth, flat cornea curvature, and thin cornea.

Age- and sex-related differences in the measures of anterior segment parameters in a myopic clinical sample using Pentacam Scheimpflug tomography.

PURPOSE: To assess age-and sex-related differences of anterior segment parameters in a myopic clinical sample. METHODS: This clinic-based retrospective study involved eligible subjects grouped into myopia (i.e., low-to-moderate) and high myopia. Demographics and anterior segment parameters measures were recorded and analyzed. RESULTS: Some 153 eligible eyes were analyzed-98 myopia and 55 high myopia-comprising 87 males and 66 females. The mean ages and ranges were 28.47 years (SD = 9.59 years), 8-50 years, and 27.82 years (SD = 9.69 years), 10-51 years, for the myopia and the high myopia groups, respectively. The means of the spherical equivalents were - 3.02 D (SD = 1.46 D, range: - 0.50 to - 5.85 D), for the myopia group and - 10.42 D (SD = 5.50 D, range: - 6.00 to - 21.86 D) for the high myopia group. No significant difference was found between degree of myopia and anterior segment measures. Males had larger anterior chamber volume (mean 175.71 ± 26.27, range: 124-225 mm3); (P = 0.007) and deeper anterior chamber depth (3.73 ± 0.27, range: 3.06-4.41 mm) (P = 0.017) than females in the myopia group. Females also had significantly steeper anterior corneal curvature, Km (ant.) but flatter posterior corneal curvature, Km (post.), (- 6.31 ± 0.25, range - 7.00 to - 5.90 D) in both the myopia group [Km (ant.): 44.06 D ± 1.33 D, range: 41.30-47.10; Km (post.): - 6.31 D ± 0.25 D, range: - 7.00 to - 5.90; P = 0.008, P = 0.002, respectively] and the high myopia group [Km (ant.): 43.79 D ± 0.33 D, range: 41.00-47.10; Km (post.): - 6.22 D ± 0.30 D, range: - 6.80 to - 5.60; P = 0.034, P = 0.049, respectively]. Age was not correlated with the anterior segment parameters in both degrees of myopia. CONCLUSION: Sex has significant influence on the corneal curvature, anterior chamber volume and anterior chamber depth regardless of the degree of myopia.

The utility of measures of anterior segment parameters of a Pentacam Scheimpflug tomographer in discriminating high myopic astigmatism from keratoconus.

The study aimed to evaluate and compare anterior segment parameters between keratoconic eyes and eyes with high myopic astigmatism using Pentacam Scheimpflug tomography. This was a retrospective cross-sectional study that included sixty keratoconic eyes (thirty-two persons) and seventy-three eyes (forty-six persons) with high myopic astigmatism with mean ages 24.72 ± 11.65years and 26.60 ± 10.69years, respectively. Twenty-three parameters from the topographic map and fifteen parameters from the Belin-Ambrosió enhanced ectasia display map of the printouts of a Scheimpflug principle-based Pentacam tomographer were evaluated for their diagnostic accuracy using Receiver Operating Characteristic (ROC) curve. All parameters except cornea volume, anterior chamber volume, and anterior chamber angle indicated a significant difference between high myopic astigmatism and keratoconic eyes. The area under the receiver operating characteristic (AUROC) of eighteen Pentacam parameters was excellent (0.9-1.0) in discriminating keratoconus from high myopic astigmatism, out of which four {anterior minimum sagittal curvature (ant. Rmin), posterior minimum sagittal curvature (post. Rmin), maximum Ambrosió relational thickness (ART max) and total deviation value (D)} indicated excellent (>90%) sensitivity and specificity in addition to the excellent AUROC values. Topographic and Belin-Ambrosió enhanced ectasia display (BAD) maps of a Scheimpflug principle-based Pentacam tomographer are useful in enhancing the diagnosis of keratoconus and may also provide valuable information in effectively screening for keratoconus cases among refractive surgery candidates with high myopic astigmatism.

Contact Lens- and Patient-related Factors Associated with Contact Lens Discomfort among Contact Lens Wearers in an African Cohort.

SIGNIFICANCE: No information is available on contact lens discomfort in any African population. Such information may be helpful in developing the scope and priorities for intervention. PURPOSE: The purpose of the study was to examine contact lens- and patient-related factors associated with contact lens discomfort among wearers in Ghana. METHODS: In this multicenter cross-sectional study, contact lens wearers 18 years and older were recruited. The Contact Lens Dry Eye Questionnaire-8 and a standardized scripted interview were administered to 72 contact lens wearers at five clinical sites, and 40 participants' lens storage cases were collected and cultured. A variety of patient- and contact lens-related factors were examined. Univariate and multivariate logistic regression modeling were used to assess risk factors associated with contact lens discomfort. RESULTS: Seventy-two contact lens wearers aged 18 to 45 years completed the study. The mean age was 27.5 ± 6.4 years, 65.3% of them were females, 86.1% wore soft contact lens, and 13.9% wore rigid gas-permeable lens. Contact lens discomfort was reported by 66.7% of the subjects. Most frequent lens storage cases isolates were Bacillus species (40%) and fungi (31.1%). Significant association was found between disinfecting with tap water (5.98; 95% confidence interval [CI], 1.22 to 29.27; P = .03), heavy visual display terminal use (3.39; 95% CI, 1.01 to 11.34; P = .05), high water content (1.16; 95% CI, 1.02 to 1.33; P = .03), and contact lens discomfort. Demographic factors, wear modality, and care solutions were not significant (all P > .05). CONCLUSIONS: In considering the use of contact lenses for refractive correction in this population, strategies for preventing contact lens discomfort that should be targeted include use of low-water-content lenses, disinfecting with multipurpose solutions, and reducing the time spent daily on visual display terminal use.

Epidemiology and clinical presentation of glaucoma in a referral facility in Ghana: Any lessons for public health intervention?

The purpose of this study was to evaluate the epidemiological and clinical profile of patients living with glaucoma and receiving care in a tertiary eye center in Ghana. This was a hospital-based retrospective study of clinical records of glaucoma patients from January 2010 to December 2019. The study involved collating demographic information of patients, clinical presentation, and the management of glaucoma. A total of nineteen thousand (19,000) charts were retrieved from the eye center's archives. Out of these, 660 (3.5%) records of patients qualified for the study and were analyzed. There were 398 (60.3%) males and 262 (39.7%) females. Their ages ranged from 9 to 86 years (mean age = 47.30; SD ± 16.86 years). The averages of ocular parameters of 1,320 eyes (660 patients) were visual acuity = 0.26 ± 0.55 logMAR; intraocular pressure: 17.31 ± 6.11 mmHg; cup-to-disc ratios: 0.67 ± 0.17 D; and the average retinal nerve fibers thickness was 95.03 ± 21.74 µm. The mainstay of treatment was the sole use of medication. Males were the major group receiving glaucoma care at the tertiary level. Glaucoma cases included juveniles but the mean age suggests most were of adult-onset. Socio-demographic characteristics affected the diagnosis and management of glaucoma among patients receiving care at a referral center. Public health, stakeholders, and policymakers' interventions can help identify individuals with glaucoma.

Optical coherence tomography indices in the diagnosis and discrimination of stages of primary open-angle glaucoma in an African population.

PURPOSE: The objective of this study was to determine the structure-function association of the optical coherence tomography (OCT) indices (retinal nerve fibre layer (RNFL), ganglion cell complex (GCC) and optic nerve head (ONH) parameters) with the visual field sensitivity and their diagnostic ability at different stages of primary open-angle glaucoma (POAG) among a population West-African descent. METHODS: The study was a clinic-based prospective study which employed purposive sampling in the recruitment of clinically diagnosed POAG and non-glaucoma patients. OCT and visual field test (VFT) results were collated. Classification of the POAG cases was done using the Hodapp-Parrish-Anderson criteria. ROC was used for assessing the diagnostic ability of OCT indices. Pearson's correlation was used to assess the structure-function association. P value < 0.05 was considered statistically significant. CONCLUSIONS: Of the 497 subjects (497 eyes), 301 (60.6%) were males and 196 (39.4%) were females. The average, superior and inferior RNFL and GCC showed a strong positive correlation with the visual field sensitivity, but the average RNFL had the highest correlation (r = 0.673, p < 0.001). The parameters of the ONH showed a moderate-to-weak correlation with the visual field sensitivity. However, there was no significant correlation between structure and function in early POAG (p > 0.05). Superior GCC showed the highest diagnostic ability for POAG (AUC = 0.655; p < 0.001) comparable to the RNFL. Macula (GCC) and (RNFL) have a comparable ability to diagnose POAG at all the stages of POAG and can be used complimentarily for glaucoma assessment and diagnosis.

The Association of Central Corneal Thickness and Intraocular Pressure Measures by Non-Contact Tonometry and Goldmann Applanation Tonometry among Glaucoma Patients.

BACKGROUND: The aim of this study was to determine whether Central Corneal Thickness (CCT) is associated with intraocular pressure measurement (IOP) with a Non-contact tonometer and the Goldmann applanation tonometer in glaucoma patients. MATERIALS AND METHODS: The study involved two hundred and thirty-two eyes of clinically diagnosed glaucoma patients receiving care at a referral facility. IOP measurements were obtained using both the Non-Contact Tonometer (NCT) and Goldmann Applanation Tonometer (GAT). The association between age, ethnicity, and CCT, as well as CCT on the measures of NCT and GAT, were analyzed. RESULTS: There were 64(55.2%) males and 52 (44.8%) females and their ages ranged from 18 to 85 years (mean age = 47.72; SD ± 15.75 years). There was a weak positive correlation between the CCT and NCT findings in the right eye (r = 0.19, n = 116, p < 0.05) and in the left eye (r = 0.25, n = 116, p < 0.05). However, there was no correlation between CCT and GAT measurements. Age had a significant correlation with CCT while gender and ethnicity had no significant correlation. CONCLUSION: The study found a significant association between CCT and NCT. However, there was no significant association between CCT and GAT. CCT had an association with age but independent of gender and ethnicity since there was no significant relationship between these variables.

Comparative Assessment of The Goldmann Applanation and Noncontact Tonometers in Intraocular Pressure Measurements in a Sample of Glaucoma Patients in the Cape Coast Metropolis, Ghana.

OBJECTIVES: The objective of the study was to explore the usage of the Goldmann applanation tonometry and noncontact tonometry interchangeably in the measurement of intraocular pressure (IOP) in glaucoma patients. MATERIALS AND METHODS: The study involved 441 clinically diagnosed glaucoma patients receiving care at a referral facility. IOP measurements were obtained using both the Noncontact tonometer and Goldmann applanation tonometer The repeatability of the measures was analyzed by comparing the repeated measures of the devices using paired t-test and calculating the correlation coefficient. A Bland-Altman analysis was used to determine the limits of agreement between the two procedures. RESULTS: There were 271 (61.5%) males and 170 (38.5%) females and their age ranged from 18 to 73 years (mean age = 49.37; standard deviation ± 14.81 years). The findings of the study showed significantly lower readings (P < 0.001) of the GAT (right eye = 17.40 ± 7.48 mmHg; left eye = 16.80 ± 7.49 mmHg) compared to the NCT (right eye = 20.15 ± 8.30 mmHg; left eye = 19.74 ± 8.31 mmHg). There was a strong positive correlation between the GAT and NCT findings in the right eye (r = 0.871, n = 441, P < 0.001) and in the left eye (r = 0.887, n = 441, P < 0.001). There was a wide limit of agreement between NCT and GAT measurements. CONCLUSION: There was statistically significant higher measures obtained with NCT than the GAT but did not exceed the allowable inter-device difference. There was a strong positive correlation between GAT and NCT measurements. However, it is strongly recommended that these devices are not used interchangeably in the monitoring of IOP in glaucoma due to the wide range of limits of agreement.