Demographic factors associated with myopia knowledge, attitude and preventive practices among adults in Ghana: a population-based cross-sectional survey.

PURPOSE: Knowledge, positive attitude and good preventive practices are keys to successful myopia control, but information on these is lacking in Africa. This study determined the KAP on myopia in Ghana. METHODS: This was a population-based cross-sectional survey conducted among adults (aged 18 years and older) living across 16 regions of Ghana between May and October 2021. Data on socio-demographic factors (sex, age, gender, level of education, working status, type of employment, monthly income, and region of residence), respondents' awareness, and knowledge, attitude and preventive practices (KAP) about myopia were collected. Composite and mean scores were calculated from eleven knowledge (total score = 61), eight attitude (48), and nine preventive practice items (33). Differences in mean scores were assessed using one-way analysis of variance (ANOVA) and standardized coefficients (ß) with 95% confidence intervals (CI), using multiple linear regression to determine the associations between the dependent (KAP) and demographic variables. RESULTS: Of the 1,919 participants, mean age was 37.4 ± 13.4 years, 42.3% were aged 18-30 years, 52.6% were men, 55.8% had completed tertiary education, and 49.2% had either heard about myopia, or accurately defined myopia as short sightedness. The mean KAP scores were 22.9 ± 23.7, 33.9 ± 5.4, and 22.3 ± 2.8, respectively and varied significantly with many of the demographic variables particularly with age group, region, marital status, and type of employment. Multiple linear regression analyses revealed significant associations between region of residence and knowledge (ß =-0.54, 95%CI:-0.87, -0.23, p < 0.001), attitude (ß =-0.24, 95%CI:-0.35,-0.14, p < 0.001) and preventive practices (ß = 0.07, 95%CI: 0.01, 0.12, p = 0.015). Preventive practices were also associated with type of employment (self-employed vs employee: ß = 0.25, 95%CI: 0.15, 4.91, p < 0.05). Knowledge scores were significantly higher in those who lived in the Greater Accra (39.5 ± 18.5) and Eastern regions (39.1 ± 17.5) and lower among those who lived in the Upper West region (6.4 ± 15.6). Government employees and those with tertiary education had significantly higher mean knowledge scores compared with non-government employees (ß = 4.56, 95%CI 1.22, 7.89, p = 0.007), and those with primary/no education (ß = 18.35, 95%CI: 14.42, 22.27, p < 0.001). CONCLUSION: Ghanaian participants had adequate knowledge of myopia but showed poor attitude and low preventive practices, which varied significantly between regions and were modified by socio-demographic factors. Further research into how education can be used to stimulate Ghanaians' engagement in preventive practices is needed.

Profiling and factors associated with glaucoma diagnostic practice in sub-Saharan Africa-a cross sectional study of Nigerian and Ghanaian optometrists.

BACKGROUND: Ghana and Nigeria are the two countries in Africa that currently run the Doctor of Optometry (OD) program in sub-Saharan Africa (SSA). Optometrists in these countries are licensed to provide glaucoma care. Despite the clinically relevant practice guidelines for glaucoma, there is no data on the practice patterns for glaucoma eye care in SSA, a region with the highest prevalence of glaucoma. This study aimed to profile glaucoma diagnosis adherence to practice guidelines among optometrists in two neighbouring anglophone countries (Nigeria and Ghana). METHODS: A web-based cross-sectional survey of practising optometrists was conducted in both countries. Each country data was weighted to reflect the total number of licensed and practising optometrists at the time of this survey. Descriptive analyses were performed against demography and practice factors using survey commands to adjust for sampling weights when estimating confidence intervals (CI) around prevalence estimates. Simple and multiple logistic regression analyses were performed to identify factors associated with glaucoma diagnosis. RESULTS: A total of 493 optometrists (238, 48.3% and 255, 51.7%) from Ghana and Nigeria respectively, responded to the survey-the first to document and compare the glaucoma diagnostic criteria between optometrists in Ghana and Nigeria. More Ghanaian than Nigerian optometrists diagnosed glaucoma and over 90% in both countries reported that they frequently performed either tonometry, visual field testing, or fundus examination during glaucoma diagnosis. Ghanaian optometrists were significantly more likely to diagnose glaucoma than Nigerian optometrists (adjusted odd ratio, AOR = 6.15, 95%CI:1.63-23.15, P = .007). Optometrists who have practiced for more than 10 years (AOR = 7.04; 95%CI:1.74-28.47, P = .006) and private practice optometrists (AOR = 3.33; 95%CI:1.13-9.83, P = .03) were more likely to diagnose glaucoma. CONCLUSIONS: The study provides information for evaluating glaucoma assessment for optometrists in both countries. Optometrists in both countries are reasonably well-equipped to diagnose glaucoma and are practicing at an adequate level, but with room for improvement.

Trends in myopia management attitudes and strategies in clinical practice: Survey of eye care practitioners in Africa.

PURPOSE: There remains a lack of information on the perception and adoption of myopia control strategies among African eye care practitioners (ECPs). This study provides an African perspective to similar previous studies conducted in other parts of the world. METHODS: A self-administered survey in English and French was distributed to ECPs across Africa. The items on the questionnaire assessed their level of concern about the increasing prevalence of paediatric myopia, perceived efficacy, opinions on, and adoption of various myopia management modalities. RESULTS: Responses were obtained from 330 ECPs working in 23 African countries. Respondents were highly concerned about the increasing prevalence of paediatric myopia in their clinic (median 8/10) and perceived approved myopia control soft contact lenses as the most effective at slowing myopia progression (mean perceived reduction in myopia progression ± SD; 53.9 ± 27.1%), followed by single vision spectacles (53.1 ± 30.9%), and orthokeratology (52.8 ± 28.0%). Multifocal soft contact lenses (40.4 ± 25.8%) and pharmaceutical agents such as topical atropine drops (39.5 ± 27.1%) were perceived as least effective in slowing myopia progression. Although ECPs reported being aware of various myopia control strategies, they still mainly prescribed single vision spectacles to a large proportion (64.3 ± 29.9%) of young progressing myopes. Nearly one-third (27%) of ECPs who prescribed single vision lenses stated they were concerned about the cost implications to patients. Other reported concerns included safety of, and inadequate information about myopia control options. CONCLUSIONS: African ECPs continue to prescribe single vision lenses for progressing myopes despite being aware of the various myopia control options. Practitioners' perceptions of the efficacy of several modalities to slow myopia progression do not align with the current best evidence. Clear practice guidelines and continuing education on myopia control are warranted to inform and guide the management of myopic patients in Africa.

Systematic review and meta-analysis of myopia prevalence in African school children.

PURPOSE: Increased prevalence of myopia is a major public health challenge worldwide, including in Africa. While previous studies have shown an increasing prevalence in Africa, there is no collective review of evidence on the magnitude of myopia in African school children. Hence, this study reviews the evidence and provides a meta-analysis of the prevalence of myopia in African school children. METHODS: This review was conducted using the 2020 Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Five computerized bibliographic databases, PUBMED, Scopus, Web of Science, ProQuest, and Africa Index Medicus were searched for published studies on the prevalence of myopia in Africa from 1 January 2000 to 18 August 2021. Studies were assessed for methodological quality. Data were gathered by gender, age and refraction technique and standardized to the definition of myopia as refractive error ≥ 0.50 diopter. A meta-analysis was conducted to estimate the prevalence. Significant heterogeneity was detected among the various studies (I2 >50%), hence a random effect model was used, and sensitivity analysis was performed to examine the effects of outliers. RESULTS: We included data from 24 quality assessed studies, covering 36,395 African children. The overall crude prevalence of myopia over the last two decades is 4.7% (95% CI, 3.9-5.7) in African children. Although the prevalence of myopia was slightly higher in females (5.3%, 95%CI: 4.1, 6.5) than in males (3.7%, 95% CI, 2.6-4.7; p = 0.297) and higher in older [12-18 years 5.1% (95% CI, 3.8-6.3) than younger children (aged 5-11 years, 3.4%, 95% CI, 2.5-4.4; p = 0.091), the differences were not significant. There was a significantly lower prevalence of myopia with cycloplegic compared with non-cycloplegic refraction [4.2%, 95%CI: 3.3, 5.1 versus 6.4%, 95%CI: 4.4, 8.4; p = 0.046]. CONCLUSIONS: Our results showed that myopia affects about one in twenty African schoolchildren, and it is overestimated in non-cycloplegic refraction. Clinical interventions to reduce the prevalence of myopia in the region should target females, and school children who are aged 12-18 years.

A Systematic Review of Current Teleophthalmology Services in New Zealand Compared to the Four Comparable Countries of the United Kingdom, Australia, United States of America (USA) and Canada.

BACKGROUND: Over 700,000 New Zealanders (NZ), particularly elderly and Maori, live without timely access to specialist ophthalmology services. Teleophthalmology is a widely recognised tool that can assist in overcoming resource and distance barriers. Teleophthalmology gained unprecedented traction in NZ during the COVID-19 pandemic and subsequent lockdown. However, its provision is still limited and there are equity issues. The aim of this study was to conduct a systematic review identifying, describing and contrasting teleophthalmology services in NZ with the comparable countries of Australia, USA, Canada and the United Kingdom. METHODS: The electronic databases Embase, PubMed, Web of Science, Google Scholar and Google were systemically searched using the keywords: telemedicine, ophthalmology, tele-ophthalmology/teleophthalmology. The searches were filtered to the countries above, with no time constraints. An integrative approach was used to synthesise findings. RESULTS: One hundred and thirty-two studies were identified describing 90 discrete teleophthalmology services. Articles spanned from 1997 to 2020. Models were categorised into general eye care (n=21; 16%); emergency/trauma (n=6; 4.5%); school screening (n=25; 19%); artificial intelligence (AI) (n=23; 18%); and disease-specific models of care (MOC) (n=57; 43%). The most common diseases addressed were diabetic retinopathy (n=23; 17%); retinopathy of prematurity (n=9; 7%); and glaucoma (n=8; 6%). Programs were mainly centred in the US (n=72; 54.5%), followed by the UK (n=29; 22%), then Canada (n=16; 12%), Australia (n=13; 10%), with the fewest identified in NZ (n=3; 2%). Models generally involved an ophthalmologist consultative service, remote supervision and triaging. Most models involved local clinicians transmitting fed-forward or live images. CONCLUSION: Teleophthalmology will likely play a crucial role in the future of eye care. COVID-19 has offered a unique opportunity to observe the use of teleophthalmology services globally. Feed-forward and, increasingly, live-based teleophthalmology services have demonstrated feasibility and cost-effectiveness in similar countries internationally. New Zealand's teleophthalmology services, however, are currently limited. Investing in strategic partnerships and technology at a national level can advance health equities in ophthalmic care.

Morphological alterations of the cornea following crosslinking treatment (CXL).

INTRODUCTION: Corneal crosslinking (CXL) has revolutionized the treatment of keratoconus during the past decade. In the present study, the morphological changes in the corneal collagen fibrils (CFs) following crosslinking treatment are described. MATERIALS AND METHODS: Ten pairs of porcine and rabbit corneas were retrieved. In each pair, one cornea was the control and the other underwent CXL treatment. The central corneal thickness (CCT) was measured before and after CXL treatment. Each treated and control cornea was examined with light microscopy and by transmission electron microscopy. RESULTS: (a) The mean CCT was significantly reduced following treatment. (b) CFs were more closely packed in the anterior region and loosely packed in the posterior region. (c) CF diameter increased significantly in the anterior and intermediate regions but declined gradually towards the deeper regions. (d) There was a statistically significant decrease in the interfibrillar distance over the different regions of the cornea, except for the posterior region in porcine corneas, where there was no change. (e) The distance between adjacent collagen lamellae was significantly decreased in all regions of treated rabbit corneas. There was no change in porcine corneas. CONCLUSION: CXL treatment resulted in increased the CF diameter and decreased interfibrillar distance in the anterior and intermediate regions, while its effects on the posterior region differed among species. The effect on interlamellar distance was more prominent in the rabbit model than the porcine model. CXL treatment stiffened the corneas by increasing CF diameter and decreasing interfibrillar distance in both rabbit and pig corneas.

Animal model with structural similarity to human corneal collagen fibrillar arrangement.

Rabbit and porcine corneas have been used in scientific research due to their structural similarity to the human cornea. Currently, there are no studies that have compared corneal collagen fibrillar diameter, interfibrillar distance and interlamellar distance between human and animal models. Ten pairs of porcine, rabbit, and human corneas were used. These were analysed using light and Transmission Electron microscopy. The collagen fibrillar diameter, interfibrillar distance and interlamellar distance were statistically compared between porcine, rabbit and human corneas. The human, porcine and rabbit; mean collagen fibrillar diameters were: 24.52 ± 2.09 nm; 32.87 ± 0.87 nm; and 33.67 ± 1.97 nm. The mean interfibrillar distances were: 46.10 ± 2.44 nm; 53.33 ± 2.24 nm; and 52.87 ± 2.73 nm, respectively. The collagen fibrillar diameter and interfibrillar distance of porcine and rabbit corneas were significantly different (p < 0.001) to the human corneal values but not form each other. The interlamellar distance of human, porcine and rabbit corneas was: 2190 ± 820 nm; 6460 ± 1180 nm; and 4410 ± 1330 nm, respectively. All the comparisons were statistically different, in porcine versus rabbit at the p < 0.01 level and both porcine and rabbit versus human at the p < 0.001 level. Histologically, all five layers (epithelium, Bowman's layer, stroma, Descemet membrane and endothelium) of the cornea were visible in all the three species. While neither animal model was structurally identical to the human cornea, they are both relatively close to being used as models to study the biomechanical effects of external insults/treatments to be extrapolated to the human cornea.

Dynamic Pupillometry in Type 2 Diabetes: Pupillary Autonomic Dysfunction and the Severity of Diabetic Retinopathy.

PURPOSE: Autonomic dysfunction may precede the microvascular changes that characterise diabetic retinopathy. The aim of this pilot study was to measure and compare pupillometry indices in type 2 diabetes (T2DM) patients - with and without diabetic retinopathy - and in healthy, age-matched controls. METHODS: Two hundred and eleven participants with T2DM aged 45-80 years were recruited from Dunedin Hospital Eye Department, Dunedin, New Zealand. They were categorised into three groups - no, mild/moderate, or severe diabetic retinopathy. Seventy age-matched, diabetes screen negative control participants were recruited from the Dunedin city community. Dynamic pupillometry was performed using an infrared pupillometer. The main outcome measures were maximum constriction velocity, average constriction velocity, absolute constriction amplitude, relative reflex amplitude, average dilation velocity and 75% re-dilation (recovery) time. Outcome measures were compared between study groups using the Kruskal-Wallis nonparametric test (with Dunn's multiple comparison post-test). RESULTS: Pupillary parasympathetic function differed between groups. Maximum constriction velocity (p <0.001) and average constriction velocity (p <0.001) were slower, and absolute constriction amplitude (p <0.001) and relative reflex amplitude (p <0.05) were lower in the three diabetes groups compared with controls. There were no significant differences in pupillary sympathetic function between the four groups for re-dilation time, but the diabetes groups had significantly slower average dilation velocity times. CONCLUSION: Pupillary light reflex is significantly impaired with diabetic retinal neuropathy, before clinically observable signs of diabetic retinopathy. Dynamic pupillometry may be a cheap, clinically relevant test, but sensitivity and specificity need to be determined before utilising as a screening tool for diabetic retinopathy.

The Detection of Spontaneous Venous Pulsation with Smartphone Video Ophthalmoscopy.

PURPOSE: Spontaneous venous pulsation (SVP) has a high negative predictive value for raised intracranial pressure and is a useful sign when assessing patients with headache. The objective was to determine if smartphone-based video ophthalmoscopy can detect SVP. PATIENTS AND METHODS: In total 233 patients and 291 eyes were recruited from the Dunedin Hospital eye clinic from July to November 2018. Patients were examined by a clinician and graded for SVP with a slit lamp and 78 Dioptre lens. Videos were taken with a smartphone ophthalmoscope and graded by two separate clinicians blinded to the slit lamp findings. RESULTS: Only 272 eyes of 215 patients were included, as others failed in the inclusion criteria for overall video quality. Sensitivity was calculated as how likely the presence of SVP on video was indicative of the presence of SVP on slit lamp. Sensitivity was 84.77% for Observer 1, with 128 videos graded as positive for SVP on video ophthalmoscopy of the 151 identified as positive on slit lamp examination. Sensitivity was 76.82% for Observer 2 with 116 videos correctly identified. The false positive rate was calculated as the number of videos graded positive for SVP that had been graded as negative on slit lamp examination. This was 10.74% for observer 1 and 31.40% for observer 2. CONCLUSION: This study demonstrates that SVP is detected by video ophthalmoscopy. This may be a useful triage, telemedicine and referral tool to be used for patients with headache in a primary care setting.

Development of an artificial intelligence system to classify pathology and clinical features on retinal fundus images.

IMPORTANCE: Artificial intelligence (AI) algorithms are under development for use in diabetic retinopathy photo screening pathways. To be clinically acceptable, such systems must also be able to classify other fundus abnormalities and clinical features at the point of care. BACKGROUND: We aimed to develop an AI system that can detect several fundus pathologies and report relevant clinical features. DESIGN: Convolutional neural network training with retrospective data set. PARTICIPANTS: Colour fundus photos were obtained from publicly available fundus image databases. METHODS: Images were uploaded to a web-based AI platform for training and validation of AI classifiers. Separate classifiers were created for each fundus pathology and clinical feature. MAIN OUTCOME MEASURES: Accuracy, sensitivity, specificity and area under receiver operating characteristic curve (AUC) for each classifier. RESULTS: We obtained 4435 images from publicly available fundus image databases. AI classifiers were developed for each disease state above. Although statistical performance was limited by the small sample size, average accuracy was 89%, average sensitivity was 75%, average specificity was 89% and average AUC was 0.58. CONCLUSION AND RELEVANCE: This study is a proof-of-concept AI system that could be implemented within a diabetic photo-screening pathway. Performance was promising but not yet at the level that would be required for clinical application. We have shown that it is possible for clinicians to develop AI classifiers with no previous programming or AI knowledge, using standard laptop computers.

Current perspectives on corneal collagen crosslinking (CXL).

Corneal collagen crosslinking has revolutionized the treatment of keratoconus and post-refractive corneal ectasia in the past decade. Corneal crosslinking with riboflavin and ultraviolet A is proposed to halt the progression of keratectasia. In the original "Conventional Dresden Protocol" (C-CXL), the epithelium is removed prior to the crosslinking process to facilitate better absorption of riboflavin into the corneal stroma. Studies analyzing its short- and long-term outcomes revealed that although there are inconsistencies as to the effectiveness of this technique, the advantages prevail over the disadvantages. Therefore, corneal crosslinking (CXL) is widely used in current practice to treat keratoconus. In an attempt to improve the visual and topographical outcomes of C-CXL and to minimize time-related discomfort and endothelial-related side effects, various modifications such as accelerated crosslinking and transepithelial crosslinking methods have been introduced. The comparison of outcomes of these modified techniques with C-CXL has also returned contradictory results. Hence, it is difficult to clearly identify an optimal procedure that can overcome issues associated with the CXL. This review provides an up-to-date analysis on clinical and laboratory findings of these popular crosslinking protocols used in the treatment of keratoconus. It is evident from this review that in general, these modified techniques have succeeded in minimizing the immediate complications of the C-CXL technique. However, there were contradictory viewpoints regarding their effectiveness when compared with the conventional technique. Therefore, these modified techniques need to be further investigated to arrive at an optimal treatment option for keratoconus.

Agreement Between Autorefraction and Subjective Refraction in Keraring-Implanted Keratoconic Eyes.

OBJECTIVES: To assess the agreement between subjective refraction and autorefraction and to explore the relationship between the magnitude of higher order aberration, and visual acuity and refraction, before and after keraring implantation. METHODS: This prospective, randomized, interventional study enrolled 27 subjects (mean age 28.1±6.5 years) with keratoconus. Noncycloplegic refraction was performed subjectively by one clinician and with an autorefractor by another clinician, before and 6 months after surgery. The limit of agreement (LoA) between methods was assessed, and the relationships between the corrected distance visual acuity, logMAR on the one hand and refraction measurements and higher-order aberrations on the other, were examined. RESULTS: The agreement in mean spherical equivalent refraction (MSER) between methods was good postoperatively but poor preoperatively. The autorefractor gave a more myopic refraction than subjective refraction preoperatively (-3.28±3.06 D; LoA -9.27 to +2.71 D, P<0.0001) and postoperatively (-0.63±1.64 D; LoA -3.85 to +2.58 D, P=0.055), and returned higher negative cylinders preoperatively (-1.10±1.17 D; LoA -3.40 to +1.19 D, P<0.0001) and postoperatively (-1.08±1.27 D; LoA -3.60 to +1.41 D, P<0.0001) in keratoconic eyes. The difference in MSER between methods was significantly related to the refractive error at both visits (P<0.05) and to the magnitude of higher-order aberrations in keratoconic eyes preoperatively (P<0.05). The logMAR visual acuity achieved subjectively worsened as the magnitude of higher-order aberrations increased preoperatively (P<0.001). CONCLUSIONS: The autorefractor returns values that are significantly more myopic in MSER and higher negative cylinders than subjective refraction, preoperatively, but the MSER was similar between devices postoperatively. The autorefactor seems a valid starting point for subjective refraction in keratoconic eyes treated with keraring, but the cylinder should be corrected by about +1 D. The instruments agree more in less myopic than high myopic eyes.

Clinical evaluation of two types of intracorneal ring segments (ICRS) for keratoconus.

PURPOSE: To compare the outcome measures following implantation of two types of ICRS. METHODS: Forty-four eyes of keratoconic patients (aged 18-50 years) were randomly assigned to femtosecond laser-assisted Keraring ICRS (Group A) or MyoRing (Group B) implantation. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, keratometry (K), and aberrations were compared preoperatively, at 3 and 6 months postoperatively. A survey was conducted to assess patient's satisfaction, 6 months postoperatively. RESULTS: In Groups A (n = 26) and B (n = 18), UDVA was increased (P < 0.05), but CDVA increased only in Group A (P < 0.05) 6 months postoperatively. The mean K was reduced by 4.55 D (P < 0.0001) in Group A and 6.51 D (P < 0.001) in Group B. Six months postoperatively, the mean refraction spherical equivalent (MRSE) decreased by 2.90 and 3.60 D in Groups A and B, respectively (P < 0.0001). Between groups, coma was more reduced (P = 0.035) in Group B than A, 6 months postoperatively. On motivation for surgery, 88.9% of patients' ranked "desire to improve unaided vision" and "relief from glasses" (77%) topmost. Seventy-seven (77%) of Group A and 89% of Group B patients were satisfied with their unaided vision at the final visit, after 6 months. CONCLUSIONS: KeraRing (A) and MyoRing (B) corneal implants both performed well in improving vision and stabilising the cornea. Implantation of the MyoRing caused greater reduction in coma and better patient satisfaction, but CDVA improved only in the Keraring group, at the final visit.

Effectiveness of in-office blood pressure measurement by eye care practitioners in early detection and management of hypertension.

AIM: To investigate the number of hypertensive patients, the optometrist is able to identify by routinely taking blood pressure (BP) measurements for patients in "at-risk" groups, and to sample patients' opinions regarding in-office BP measurement. Many of the optometrists in Saudi Arabia practice in optical stores. These stores are wide spread, easily accessible and seldom need appointments. The expanding role of the optometrist as a primary health care provider (PHCP) and the increasing global prevalence of hypertension, highlight the need for an integrated approach towards detecting and monitoring hypertension. METHODS: Automated BP measurements were made twice (during the same session) at five selected optometry practices using a validated BP monitor (Omron M6) to assess the number of patients with high BP (HBP) -in at-risk groups-visiting the eye clinic routinely. Prior to data collection, practitioners underwent a two-day training workshop by a cardiologist on hypertension and how to obtain accurate BP readings. A protocol for BP measurement was distributed and retained in all participating clinics. The general attitude towards cardiovascular health of 480 patients aged 37.2 (±12.4)y and their opinion towards in-office BP measurement was assessed using a self-administered questionnaire. RESULTS: A response rate of 83.6% was obtained for the survey. Ninety-three of the 443 patients (21.0%) tested for BP in this study had HBP. Of these, (62 subjects) 66.7% were unaware of their HBP status. Thirty of the 105 subjects (28.6%) who had previously been diagnosed with HBP, still had HBP at the time of this study, and only 22 (73.3%) of these patients were on medication. Also, only 25% of the diagnosed hypertensive patients owned a BP monitor. CONCLUSION: Taking BP measurements in optometry practices, we were able to identify one previously undiagnosed patient with HBP for every 8 adults tested. We also identified 30 of 105 previously diagnosed patients whose BP was poorly controlled, twenty-two of whom were on medication. The patients who participated in this study were positively disposed toward the routine measurement of BP by optometrists.

One-Year Clinical Outcomes of a Two-Step Surgical Management for Keratoconus-Topography-Guided Photorefractive Keratectomy/Cross-Linking After Intrastromal Corneal Ring Implantation.

PURPOSE: To present the results of same-day topography-guided photorefractive keratectomy (TG-PRK) and corneal collagen cross-linking (CXL) after intrastromal corneal ring (ISCR) implantation in patients with keratoconus. METHODS: Thirty-three patients (41 eyes) aged between 19 and 45 years were included in this prospective study. All patients underwent a femtosecond laser-enabled (Intralase FS; Abbott Medical Optics, Inc.) placement of intracorneal ring segments (Kerarings; Mediphacos, Brazil). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and keratometry readings remained stable for 6 months. Same-day PRK and CXL was subsequently performed in all patients. RESULTS: After 12 months of completion of the procedure, mean UDVA in log of minimal angle of resolution was significantly improved (0.74±0.54-0.10±0.16); CDVA did not improve significantly but 85% of eyes maintained or gained multiple lines of CDVA; mean refraction spherical equivalent improved (from -3.03±1.98 to -0.04±0.99 D), all keratometry readings were significantly reduced, from preoperative values, but coma did not vary significantly from preoperative values. Central corneal thickness and corneal thickness at the thinnest point were significantly (P<0.0001) reduced from 519.76±29.33 and 501.87±31.50 preoperatively to 464.71±36.79 and 436.55±47.42 postoperatively, respectively. Safety and efficacy indices were 0.97 and 0.88, respectively. From 6 months up until more than 1 year of follow-up, further significant improvement was observed only for UDVA (P<0.0001). CONCLUSIONS: Same-day combined TG-PRK and CXL after ISCR implantation is a safe and effective option for improving visual acuity and visual function, and it halts the progression of the keratoconus. The improvements recorded after 6 months of follow-up were maintained or improved upon 1 year after the procedure.

Reliability and reproducibility of a handheld videorefractor.

PURPOSE: To assess the performance of the 2Win eccentric videorefractor in relation to subjective refraction and table-mounted autorefraction. METHODS: Eighty-six eyes of 86 adults (46 male and 40 female subjects) aged between 20 and 25 years were examined. Subjective refraction and autorefraction using the table-mounted Topcon KR8800 and the handheld 2Win videorefractor were carried out in a randomized fashion by three different masked examiners. Measurements were repeated about 1 week after to assess instrument reproducibility, and the intertest variability was compared between techniques. Agreement of the 2Win videorefractor with subjective refraction and autorefraction was assessed for sphere and for cylindrical vectors at 0 degrees (J0) and 45 degrees (J45). RESULTS: Reproducibility coefficients for sphere values measured by subjective refraction, Topcon KR8800, and 2Win (±0.42, ±0.70, and ±1.18, respectively) were better than their corresponding J0 (±1.0, ±0.85, and ±1.66) and J45 (±1.01, ±0.87, and ±1.31) vector components. The Topcon KR8800 showed the most reproducible values for mean spherical equivalent refraction and the J0 and J45 vector components, whereas reproducibility of spherical component was best for subjective refraction. The 2Win videorefractor measurements were the least reproducible for all measures. All refractive components measured by the 2Win videorefractor did not differ significantly from those of subjective refraction, in both sessions (p > 0.05). The Topcon KR8800 autorefractometer and the 2Win videorefractor measured significantly more positive spheres and mean spherical equivalent refraction (p < 0.0001), but the J0 and J45 vector components were similar (p > 0.05), in both sessions. CONCLUSIONS: The 2Win videorefractor compares well, on average, with subjective refraction. The reproducibility values for the 2Win videorefractor were considerably worse than either subjective refraction or autorefraction. The wide limits of reproducibility of the 2Win videorefractor probably limit its usefulness as a primary screening device.

Factors influencing Saudi Arabian optometry candidates' career choices and institution of learning. Why do Saudi students choose to study optometry?

BACKGROUND: Optometry is a primary health-care profession (PHCP) and this study aimed to elucidate the factors influencing the choice of optometry as a career for Saudi students, the students' perceptions of optometry and the effect of gender. METHODS: Two hundred and forty-seven students whose average age was 21.7 ± 1.5 (SD) years and who are currently enrolled in two colleges of optometry in Saudi Arabia--King Saud University (KSU) and Qassim University (QU)--completed self-administered questionnaires. The survey included questions concerning demography, career first choice, career perception and factors influencing career choices. RESULTS: The response rate was 87.6 per cent and there were 161 male (64.9 per cent) students. Seventy-nine per cent of the participants were from KSU (males and females) and 20.6 per cent were from QU (only males). Seventy-three per cent come from Riyadh and 19 per cent are from Qassim province. Regarding the first choice for their careers, the females (92 per cent) were 0.4 times more likely (p = 0.012) to choose optometry than males (78.3 per cent). The males were significantly more likely to be influenced by the following factors: the Doctor of Optometry (OD) programs run at both universities, good salary and prospects (p < 0.05, for all). The women were significantly less likely to be influenced by another individual (p = 0.0004). Generally, more than two-thirds of the respondents viewed the desire to help others, professional prestige and the new OD programs as the three most influential factors in opting for a career in optometry. CONCLUSION: Females were more likely to opt for a career in optometry and males were more likely to be influenced by the new OD programs, good salary and job prospects. Service provision to others in the community was a primary motivation to opt for a career in optometry among young Saudis.