Fixation disparity and refractive error among first-year optometry students / Disparidad de fijación y error de refracción entre estudiantes de primer año de optometría

Purpose: To determine the fixation disparity and refractive error of first-year optometry students to ascertain any relationship between them and also identify any association between fixation disparity and visual symptoms at near. Method: It was an analytical cross-sectional study involving 85 participants aged 17 to 27 years (18.60 ± 1.37), 41% of whom were males. Subjective refraction was done at 3 m and fixation disparity was measured with and without spectacle correction using the Wesson Fixation Disparity Card. All analysis was set within a 95% confidence interval with a p-value ≤ 0.05 considered statistically significant. Results: Refractive error ranged from 0.25 SEQ (spherical equivalent) to 5.50 SEQ. Mean fixation disparity ranged from 2.9 ± 2.6 to 3.9 ± 2.8 min arc. There was no statistically significant correlation between refractive error and fixation disparity without correction (r = −0.180, p = 0.098) and with correction (r = 0.155, p = 0.157). For fixation disparity in the ortho and exo direction, mean fixation disparity with correction of participants who experienced headaches during or after reading (5.1 ± 2.6 min arc) was significantly higher (p = 0.032) than participants who did not (2.0 ± 2.6 min arc). Conclusion: Myopia is common among first-year optometry students. Refractive error has no significant effect on fixation disparity. Headache is significantly associated with exo fixation disparity at near.(AU)

Fixation disparity and refractive error among first-year optometry students.

PURPOSE: To determine the fixation disparity and refractive error of first-year optometry students to ascertain any relationship between them and also identify any association between fixation disparity and visual symptoms at near. METHOD: It was an analytical cross-sectional study involving 85 participants aged 17 to 27 years (18.60 ± 1.37), 41% of whom were males. Subjective refraction was done at 3 m and fixation disparity was measured with and without spectacle correction using the Wesson Fixation Disparity Card. All analysis was set within a 95% confidence interval with a p-value ≤ 0.05 considered statistically significant. RESULTS: Refractive error ranged from 0.25 SEQ (spherical equivalent) to 5.50 SEQ. Mean fixation disparity ranged from 2.9 ± 2.6 to 3.9 ± 2.8 min arc. There was no statistically significant correlation between refractive error and fixation disparity without correction (r = -0.180, p = 0.098) and with correction (r = 0.155, p = 0.157). For fixation disparity in the ortho and exo direction, mean fixation disparity with correction of participants who experienced headaches during or after reading (5.1 ± 2.6 min arc) was significantly higher (p = 0.032) than participants who did not (2.0 ± 2.6 min arc). CONCLUSION: Myopia is common among first-year optometry students. Refractive error has no significant effect on fixation disparity. Headache is significantly associated with exo fixation disparity at near.

Ophthalmic services utilisation and associated factors in the Ashanti region, Ghana

Objective: This survey determined the utilisation of eye care services and associated factors among adults in the Ashanti region of Ghana. Design: A population-based cross-sectional descriptive study Method: Data for this study was collected from 1615 randomly selected individuals in the Ashanti region of Ghana, using a structured, pretested interviewer-guided questionnaire. Information regarding the accessibility and determinants of, and barriers to, eye care services was based on self-reports, using the WHO Eye Care Services Assessment Questionnaire. Inferential analyses were performed using the chi-square test for statistical significance, set at p=0.05.Setting: Ashanti Region, Ghana Participants: One thousand six hundred and fifteen randomly selected adults Results: Public eye care facilities were used by 58.2% of the participants for their last eye exam. Of the participants, 47.0% had travelled less than five kilometres for their last eye exam. Waiting time and service cost were participants' most frequently cited challenges in seeking care. No need felt (40.1%), self-medication (37.7%) and cost (22.2%) were the most frequently mentioned barriers to seeking ophthalmic services. Conclusion: The major challenges encountered in seeking eye care services were waiting time and cost of service. Major barriers to ophthalmic services utilisation were no need felt, self-medication and cost. Factors such as cost, lack of felt need and self-medication, which serve as barriers to utilising eye care services, should be addressed by stakeholders through eye health education and promotion

Prevalence of keratoconus in Ghana: A hospital-based study of tertiary eye care facilities.

PURPOSE: To estimate the prevalence of keratoconus in tertiary eye care facilities in Ghana. METHODS AND ANALYSIS: In this hospital-based retrospective cohort study, medical records of patients from tertiary/referral eye care facilities in Ghana were reviewed. Included in the study were records of individuals who visited the eye care facilities and were diagnosed of keratoconus within the period of January 2016 to December 2019 inclusive. Data on patients' demographics, severity of keratoconus, mode of diagnosis, treatment, and visual acuity outcomes were analysed. RESULTS: Out of the total of 142,209 records reviewed, 75 patients were diagnosed of keratoconus in at least one eye (127 eyes; 86.8% bilateral cases), representing a prevalence estimate of 53 per 100000 (95% confidence interval (CI): 41 to 65 per 100000). The mean ± SD age of patients at the time of diagnosis was 21.1 ± 9.5 years (66.2% males). The mean ± SD keratometry in keratoconus patients was 52.1 ± 7.0: majority (76.5%) of the cases were moderate to severe keratoconus. The main primary treatment regimen was corneal transplant (58.8%) followed by spectacles (25.0%), crosslinking (8.8%) and rigid contact lens (7.3%). There was a significant association between post-treatment visual acuity outcomes and treatment type (p < 0.001). CONCLUSION: Our study represents the first prevalence estimate of keratoconus in Ghana. The prevalence of keratoconus estimated in our study is lower than that reported in countries with tropical climates. This could be due to lower uptake of referrals, underdiagnosis and/or misdiagnosis of the condition in lower-level health facilities.

Relationship between peripheral refraction, axial lengths and parental myopia of young adult myopes

Purpose: To determine the relationship between peripheral refraction at the horizontal retina, axial length and parental history of myopia between myopic adults who have positive parental myopia and those with negative parental myopia.Methods: 69 males and 44 females in the age range of 18–25 years were assigned either a negative parental myopia (NPM) or positive parental myopia (PPM) group. In the corrected and uncorrected states, peripheral refractive error was measured up to 30° horizontally in 10° steps using an open field autorefractor. Axial length was measured using an Opto US1000 Fine A-Scan Ultrasonography (model US1000).Results: Relative peripheral refractive error showed more hyperopic defocus that was statistically significantly more increased in the positive parental myopia group than in the negative parental myopia group (P ≥ 0.02). The overall mean ± SD axial length of all subjects was 23.38 ± 0.32 mm (range 23.01–25.01 mm). The study showed a statistically significant difference (P = 0.005) in axial lengths of young adult myopes (23.45 ± 0.36 mm) with parental myopia compared to those with similar spherical equivalent refraction who have non-myopic parents (23.28 ± 0.19 mm).Conclusion: There was significantly more hyperopic defocus at 30° N and 30° T retina in the corrected states of young adult myopes who had myopic parents compared to their counterparts with non-myopic parents. (AU)

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.

Relationship between peripheral refraction, axial lengths and parental myopia of young adult myopes.

PURPOSE: To determine the relationship between peripheral refraction at the horizontal retina, axial length and parental history of myopia between myopic adults who have positive parental myopia and those with negative parental myopia. METHODS: 69 males and 44 females in the age range of 18-25 years were assigned either a negative parental myopia (NPM) or positive parental myopia (PPM) group. In the corrected and uncorrected states, peripheral refractive error was measured up to 30° horizontally in 10° steps using an open field autorefractor. Axial length was measured using an Opto US1000 Fine A-Scan Ultrasonography (model US1000). RESULTS: Relative peripheral refractive error showed more hyperopic defocus that was statistically significantly more increased in the positive parental myopia group than in the negative parental myopia group (P ≥ 0.02). The overall mean ± SD axial length of all subjects was 23.38 ± 0.32 mm (range 23.01-25.01 mm). The study showed a statistically significant difference (P = 0.005) in axial lengths of young adult myopes (23.45 ± 0.36 mm) with parental myopia compared to those with similar spherical equivalent refraction who have non-myopic parents (23.28 ± 0.19 mm). CONCLUSION: There was significantly more hyperopic defocus at 30° N and 30° T retina in the corrected states of young adult myopes who had myopic parents compared to their counterparts with non-myopic parents.

Assessment of availability, awareness and perception of stakeholders regarding preschool vision screening in Kumasi, Ghana: An exploratory study.

BACKGROUND: Regardless of the importance of preschool vision screening (PSVS), there is limited data on the current state of these programs in Africa (particularly Ghana). This study sought to investigate the level of awareness and perception of stakeholders regarding PSVS, its availability and related policies/programmes in the Kumasi Metropolis, Ghana. METHODS: This descriptive cross-sectional study included 100 systematically sampled preschools in the metropolis (using probability proportional-to-size method); 72 private schools and 28 public schools. Convenience sampling was used to recruit stakeholders of preschools (teachers, head teachers, proprietors, administrators, directors, and educationists), and were interviewed using a well-structured questionnaire. Questionnaires were administered to all eligible respondents who were present at the time of data collection. RESULTS: A total of 344 respondents participated in the study; 123 (35.8%) males and 221 (64.2%) females. The overall mean age of respondents was 37.63 ±12.20 years (18-71 years). Of the respondents, 215 (62.5%), 94 (27.3%), and 35 (10.2%) were enrolled from private schools, public schools, and Metropolitan Education Directorate, respectively. 73.8% of respondents reported the absence of routine PSVS in schools whereas 90.1% reported no written policies for PSVS in schools. Only 63.6% of respondents were aware of PSVS whereas more than half (59.6%) of all respondents perceived PSVS to be very important for preschoolers. Private school ownership was significantly associated with availability of PSVS whereas age, teachers, private school ownership, and preschool experience > 10 years were significantly associated with awareness of PSVS (P < 0.05). However, there was no significant association between sociodemographic factors and perception of PSVS. CONCLUSION: PSVS is largely unavailable in most Ghanaian schools. Majority of stakeholders were aware of PSVS and agreed to its implementation and incorporation into schools' health programmes. There is the need to implement a national programme/policy on preschool vision screening in Ghana.

Refractive error and visual impairment in private school children in Ghana.

PURPOSE: To assess the prevalence of refractive error and visual impairment in private school children in Ghana. METHODS: A random selection of geographically defined classes in clusters was used to identify a sample of school children aged 12 to 15 years in the Ashanti Region. Children in 60 clusters were enumerated and examined in classrooms. The examination included visual acuity, retinoscopy, autorefraction under cycloplegia, and examination of anterior segment, media, and fundus. For quality assurance, a random sample of children with reduced and normal vision were selected and re-examined independently. RESULTS: A total of 2454 children attending 53 private schools were enumerated, and of these, 2435 (99.2%) were examined. Prevalence of uncorrected, presenting, and best visual acuity of 20/40 or worse in the better eye was 3.7, 3.5, and 0.4%, respectively. Refractive error was the cause of reduced vision in 71.7% of 152 eyes, amblyopia in 9.9%, retinal disorders in 5.9%, and corneal opacity in 4.6%. Exterior and anterior segment abnormalities occurred in 43 (1.8%) children. Myopia (at least -0.50 D) in one or both eyes was present in 3.2% of children when measured with retinoscopy and in 3.4% measured with autorefraction. Myopia was not significantly associated with gender (P = 0.82). Hyperopia (+2.00 D or more) in at least one eye was present in 0.3% of children with retinoscopy and autorefraction. CONCLUSIONS: The prevalence of reduced vision in Ghanaian private school children due to uncorrected refractive error was low. However, the prevalence of amblyopia, retinal disorders, and corneal opacities indicate the need for early interventions.