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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. [ABSTRACT FROM AUTHOR]

Background: Repeatability and validity are important components of precision in any measurement system. Aim: This study aimed to determine the effect of change in head and neck position and body posture on the repeatability of intraocular pressure (IOP) measurements with PT-100 non-contact tonometer and compare with Goldmann, PT-100 and Schiøtz tonometer readings. Setting: Optometry clinic, Saudi Arabia. Methods: The IOP was measured in one selected eye of 84 healthy participants (mean aged 21.9 ± 2.0 years) using PT-100 in three head and body positions, Goldmann tonometer and Schiøtz on two separate visits, in a randomised fashion. Central corneal thickness (CCT) was measured using an ultrasound pachymeter. The repeatability, agreement and correlations between CCT and IOP differentials were assessed. Results: The IOP measured in three head and body positions with the PT-100 were similar and comparable to Goldmann IOPs in sessions one and two with 74% and 86% of PT-100 measurements within ±3 mmHg of the Goldmann tonometry, respectively, for sessions one and two. The Schiøtz tonometer-measured IOP was higher than the Goldmann IOPs (p < 0.05) with 60% and 44% of Schiøtz IOPs within ±3 mmHg of the Goldmann tonometer IOP in sessions one and two, respectively. The limits of repeatability and reproducibility were best with the PT-100 and worst with the Schiøtz tonometer. The mean CCT (552±36 µm) was negatively correlated with differences between Goldmann and both PT-100 and Schiøtz-measured IOP. Conclusion: Postural changes did not affect the validity and repeatability of PT-100 readings. PT-100 measurements were interchangeable with Goldmann tonometer. Schiøtz overestimated Goldmann IOP in thicker corneas more than the PT-100. [ABSTRACT FROM AUTHOR]

Background: Over 700,000 New Zealanders (NZ), particularly elderly and Māori, 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 [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose: To compare the effect of nonpreserved oxybuprocaine and preserved artificial tears on central corneal thickness (CCT) obtained by 2 pachymeters. Methods: In this prospective, placebo-controlled study, involving a random sample of 100 eyes of 50 subjects, aged 24±2.3 years, CCT readings were obtained in 2 separate sessions with the Topcon SP-3000P and ultrasound pachymetry (USP), respectively, before, 5 and 10 min after instillation of a drop each of either oxybuprocaine hydrochloride (oxybuprocaine HCl) (group 1) or carboxymethylcellulose sodium, thera tears (group 2), and placebo. Results: The baseline mean CCT for SP-3000P was 509±38 μm and 542±36 μm for USP. No statistical significant differences between baseline CCTs ( P>0.05 for both devices) in both groups. In both group experimental eyes, neither SP-3000P nor USP-measured CCTs varied significantly from the control eyes at 5 ( P>0.05) and 10 ( P>0.05) mins postinstillation of drops in both sessions. In group one, the 95% confidence intervals (CIs) for the SP-3000P CCTs were similar at 5 (−16 to 17 μm) and 10 min (−16 to 17 μm), but in the USP-measured CCTs, it was wider at 10 min (−41 to 46 μm) than at 5 min (−30 to 41 μm) postinstillation. In group two, the 95% CIs at 5 and 10 mins postinstillation, respectively, ranged between −20 and 47 μm, −21 and 43 μm (SP-3000P) and −29 and 23 μm, −26 and 23 μm (USP). Within groups and between groups, variations in CCT were similar at both times intervals in all comparisons. Conclusion: Although oxybuprocaine HCl and thera tears consistently did not affect the mean CCT obtained by both devices at both time intervals, variation in SP-3000P measured CCT was more consistent in both sessions and narrower in relation to USP-measured CCT. It may be reasonable to suggest that measurements of CCT in normal patients be taken before examinations requiring instillation of anesthetics or such measurements when obtained postinstillation of either oxybuprocaine or preserved artificial tears be interpreted with caution. [ABSTRACT FROM AUTHOR]

Purpose: To compare the effect of tetracaine 1% on central corneal thickness (CCT) measurements obtained by the ultrasound pachymetry (USP) and Topcon SP-3000P specular microscope. Methods: In the following sequence, SP-3000P before anesthesia, USP before anesthesia, SP-3000P 10 mins after anesthesia, USP 10 mins after anesthesia, CCT measurements were obtained from 100 randomly selected eyes of 50 oculo-visually young adults in 2 measurement sessions. Results: The CCT before instilling anesthetic did not vary significantly in each technique within session ( P>0.05) and between sessions ( P>0.05). Baseline CCT measurements obtained by the USP were significantly ( P<0.0001) higher than that of SP-3000P by about 28 μm and 29 μm in sessions 1 and 2, respectively. A small but statistically insignificant increase in CCT ( P>0.05) was observed 10 mins after instilling one drop of 1% tetracaine in both sessions of SP-3000P, whereas a statistically significant increase ( P<0.05) in CCT in both sessions of USP was observed. The precision of the effects of anesthesia in the USP for sessions 1 and 2 was±15 μm and±31 μm, and in SP-3000P sessions 1 and 2, respectively, was±16 μm and±13 μm. Conclusion: Topical anesthetic might have an effect on CCT measurements made with the ultrasound pachymeter. Such an effect could be due to instability of the tear film caused by the anesthetic, and this effect was not measurable with the SP-3000P suggesting that the difference in the principles of operation of both pachymetry devices might play a significant role in the detection of changes in CCT induced by topical anesthetic and the difference in CCT measurements observed between techniques. [ABSTRACT FROM AUTHOR]

Background: The intraocular pressures and biomechanical parameters measured by the ocular response analyzer make the analyzer a useful tool for the diagnosis and management of anterior segment disease. This observational study was designed to investigate the effect of topical anesthesia on the parameters measured by the ocular response analyzer: corneal hysteresis, corneal resistance factor, Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc). Methods: Two sets of measurements were made for 78 eyes of 39 subjects, approximately 1 week apart. In session 1, each eye of each subject was randomized into one of three groups: polyvinyl alcohol (0.5%), tetracaine hydrochloride (0.5%), or oxybuprocaine hydrochloride (0.4%). In session 2, eyes that were in the polyvinyl alcohol group in session 1 were assigned to the tetracaine group, those in the tetracaine group in session 1 were assigned to oxybuprocaine group, and those in the oxybuprocaine group in session 1 were assigned to the polyvinyl alcohol group. For both sessions, each subject first had his or her central corneal thickness assessed with a specular microscope, followed by measurements of intraocular pressure and corneal biomechanical parameters with the Ocular Response Analyzer. All measurements were repeated for 2 minutes and 5 minutes following the instillation of either polyvinyl alcohol, tetracaine, or oxybuprocaine. The level of statistical significance was 0.05. Results: Polyvinyl alcohol, tetracaine hydrochloride, and oxybuprocaine hydrochloride had no statistically significant (P > 0.05) effect on any of the biomechanical parameters of the cornea. There was no statistically significant effect on either IOPg (P > 0.05) or IOPcc (P > 0.05) 2 minutes after the eye drops were instilled in either session. Five minutes after the eye drops were instilled, polyvinyl alcohol showed no statistically significant effect on either IOPg (P > 0.05) or IOPcc (P > 0.05) in either session. Oxybuprocaine and tetracaine caused statistically significant (P < 0.05) reductions in IOPg in session 1, but only tetracaine had a significant (P < 0.05) effect in session 2. Tetracaine also caused a statistically significant (P < 0.05) reduction in IOPcc in session 1. Conclusion: The statistically significant effect of topical anesthesia on IOPg varies with the anesthetic used, and while this effect was statistically significant in this study, the small effect is probably not clinically relevant. There was no effect on any of the biomechanical parameters of the cornea. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to assess the repeatability and limits of agreement of corneal thickness values measured by a high-frequency ultrasound (Artemis-2), hand-held ultrasound pachymeter (DGH-500) and a specular microscope (SP-3000P). Methods: Central corneal thickness (CCT) was analyzed in this prospective randomized study that included 32 patients (18 men and 14 women) aged 21-24 years. Measurements were obtained in two sessions, one week apart, by two examiners with three devices in a randomized order. Nine measurements were taken (three with each device) on one randomly selected eye of each patient in each measurement session. The coefficient of repeatability and interobserver reproducibility for the values of each method were calculated. The limits of agreement between techniques were also evaluated. Results: There were no significant differences in CCT values between sessions for each of the three devices (P > 0.05). The repeatability coefficients for the Artemis-2 (±8 μm/±9 μm) were superior to those of the SP-3000P (±9 μm/±11 μm) and DGH 500 (±12 μm/±12 μm) in session 1/session 2 respectively, while the interobserver reproducibility index (differences between session 1 and session 2) was superior for the SP-3000P (±17 μm) with respect to DHG-500 (±29 μm) and the Artemis-2 (±31 μm). In session 1 and session 2, the limits of agreement between the techniques were 35 μm to -31 μm and 34 to -20 μm, respectively, for DGH-500 versus Artemis-2, 73 μm to 3 μm and 60 μm to 9 μm for Artemis-2 versus SP-3000P, and 58 μm to 22 μm and 72 μm to 10 μm for DGH-500 versus SP-3000P comparisons. The DGH-500 and Artemis-2 gave similar values (P > 0.05) in both sessions, but both (Artemis-2 and DGH-500) values were significantly greater than that of the SP-3000P (P < 0.05) in both sessions. Conclusion: Repeatability was comparably good for the three techniques. However, interobserver reproducibility was approximately twice as good with the SP-3000P compared with the other two devices. The Artemis-2 CCT values consistently agreed with the DGH-500 and less so with the SP-3000P. The Artemis-2 provided CCT values that were, on average, 38 μm and 34 μm greater than that of the SP-3000P in session 1 and session 2, respectively. [ABSTRACT FROM AUTHOR]

Purpose: Comparison of the magnitude and repeatability of the intraocular pressure (IOP) measured with the Ocular Response Analyzer (ORA) to that measured with the Goldmann tonometer. Methods: Two sets of IOP measurements were made, for 89 eyes of eighty-nine subjects, approximately 1-week apart. Goldmann tonometry was performed subsequent to non-contact tonometry, in which the order of measurement was randomized between the ORA and the Topcon CT80 non-contact tonometer (CT80). Each method was assessed twice for intrasession repeatability. The limits of agreement between each non-contact pressure and that measured with the Goldmann tonometer were assessed once per session. The level of statistical significance was 0.05. Results: The mean differences between the ORA-corneal compensated, Goldmann-correlated, and CT80-IOP (ORA-IOPcc; ORA-IOPg and CT80-IOP) versus the Goldmann IOP were −0.3 ± 2.7 mmHg (mean ± SD), −0.3 ± 2.2 mmHg and −0.3 ± 2.1 mmHg, respectively for session 1 and 0.3 ± 3.0 mmHg, 0.2 ± 2.2 mmHg, and −0.5 ± 2.2 mmHg, respectively, for session 2. The repeatability coefficients were ± 5.3 mmHg, ± 4.2 mmHg, ± 2.5 mmHg, and ± 1.9 mmHg, respectively for ORA-IOPcc, ORA-IOPg, CT80-IOP, and Goldmann IOP in session 1 and ± 3.8 mmHg, ± 3.6 mmHg, ± 1.6 mmHg, and ± 1.9 mmHg, respectively for session 2. Conclusion: The repeatability indices for the ORA were poorer than those with the Goldmann tonometer and the CT80 in both sessions. However, the average IOP measured with the ORA did not vary significantly from those measured with the other two tonometers in either session. The ORA provides valid, repeatable measures of IOP. [ABSTRACT FROM AUTHOR]

Background: Several authors believe it is necessary to randomise the order in which contact and non-contact tonometers are used in comparison studies. This study was carried out to investigate the effect of repeated applanation on the measured intraocular pressure. Methods: One set of measurements per session was made on each of three sessions (one session per day) with the Goldmann and two non-contact tonometers (Topcon CT80 and Keeler Pulsair EasyEye), in a pre-determined order, on one randomly selected eye of 120 subjects randomised to one of two groups. For session one, only the non-contact tonometers were used to assess the intraocular pressure of both groups. For session two, either non-contact or Goldmann tonometry was performed first and this order was reversed for session 3. Average intraocular pressures were compared between sessions to determine the presence or absence of effects on the intraocular pressure caused by prior repeated applanation with the Goldmann or either one (or both) of the non-contact tonometers. Results: Prior applanation with a non-contact tonometer did not cause a significant (p > 0.05) reduction of the mean pressure measured with either non-contact tonometer. The mean pressure was slightly but significantly (p < 0.05) reduced (for both non-contact tonometers in both subject groups) when non-contact tonometry was performed after Goldmann tonometry. There was no significant difference (p > 0.05) between the pressures measured with the Goldmann tonometer prior to and subsequent to non-contact tonometry, in both subject groups. Conclusion: A small but statistically significant reduction in the intraocular pressure was found following applanation with the Goldmann tonometer but not with either one of two non-contact tonometers. [ABSTRACT FROM AUTHOR]

Background: In studies aimed at assessing the accuracy and repeatability of non-contact tonometers, the order in which these tonometers and the Goldmann tonometer are used is usually randomised despite studies in the literature that demonstrate an ocular massage effect that occurs post-applanation but not after non-contact tonometry. The purpose of this study was to investigate the effect of repeated corneal applanation on subsequent assessments of IOP. Methods: Data were obtained from 65 left eyes of 65 young, oculovisual normals. Three sets of IOP measurements were obtained, one set with the Goldmann applanation tonometer and two with the Topcon CT80 non-contact tonometer (one set each before and after applanation with the Goldmann tonometer), in each one of two separate measurement sessions, one week apart. Results: The average (and SD) IOP measured with the Goldmann tonometer in the first session (14.8 ± 2.9 mmHg) did not vary significantly from the IOP measured with the non-contact tonometer (pre-applanation) in both sessions or with the average Goldmann IOP in the second session. The bias (mean difference ± SD) between methods was 0.3 ± 1.4 mmHg and 0.4 ± 1.4 mmHg, respectively, for the first and second sessions, with the CT80 (pre-applanation) recording the higher IOP in both sessions. The within-session repeatability coefficients were ±2.3 mmHg, ±2.6 mmHg, ±2.1 mmHg and ±2.0 mmHg for the CT80 (pre-applanation) in the first and second sessions, and the Goldmann tonometer in the first and second sessions, respectively. Test-retest repeatability coefficients were ±2.8 mmHg and ±2.5 mmHg for the CT80 (pre-applanation) and the Goldmann tonometer respectively. Post-applanation with the Goldmann tonometer, there was a statistically significant (p < 0.05) reduction (1.5 ± 1.2 mmHg in session 1) in the IOP measured with the non-contact tonometer in both sessions. Conclusion: These results suggest that repeated corneal applanation leads to a statistically significant reduction in IOP on subsequent measurements. [ABSTRACT FROM AUTHOR]

Background: The reliability of non-contact tonometers has been reported extensively in the literature. This study was designed to assess reliability of the new Topcon CT80 non-contact tonometer in normotensive subjects, using the Goldmann tonometer as the standard. Methods: The accuracy of the Topcon CT 80 non-contact tonometer was assessed by comparing its IOP assessments with those of the Goldmann applanation tonometer, on 60 right eyes of young healthy subjects with normal intraocular pressures. Each subject’s intraocular pressure was assessed with each technique on two separate occasions, one week apart. The reliability of each technique was determined by the assessment of its inter-session repeatability using the Bland-Altman method. The 95 per cent limits of agreement for the two methods were also determined. Results: No statistically significant difference was found between the average intraocular pressures measured with the two techniques (p > 0.05). The inter-session repeatability indices for the two techniques did not differ significantly (p > 0.05). The mean difference in intraocular measurements between the two techniques was 0.2 ± 1.5 mmHg (mean ± SD) and the 95 per cent limits of agreement were -3.14 and +2.74 mmHg, with the non-contact tonometer returning higher readings than the Goldmann tonometer. Conclusion: In this sample of normotensive subjects, the Topcon CT80 non-contact tonometer proved to be accurate and as reliable as the Goldmann tonometer in the assessment of intraocular pressure. Thus, it can be used as an objective clinical method for the assessment of normal intraocular pressure. [ABSTRACT FROM AUTHOR]

Purpose: To compare the axial anterior chamber depth (ACD) using the Smith method, in patients under treatment for primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG), with an age-matched control group.Materials and Methods: Triplicate just-touching-slit-length (JTSL) measurements of the axial anterior chamber depth were determined in 198 eyes of 99 patients (39 control; 36 POAG; and 24 PACG) recruited from King Saud University clinics, Riyadh, Saudi Arabia. Goldmann tonometry and gonioscopy were carried out as a part of the patient's routine examination. Subjects with a history of intraocular surgery for glaucoma or any other anterior segment disease were excluded form the study. The average ACD estimate by the JTSL method were compared among the various groups.Results: The average JTSL estimates were: Control group 2.33+/-0.68 mm (axial ACD estimate = JTSL estimate x 1.4); POAG group 1.98+/-0.97 mm; PACG group 0.65+/-0.41 mm. There was no significant reduction (P = 0.068) of the JTSL estimate in the POAG group, compared to the control group. There was a statistically significant (P < 0.001) reduction of the JTSL estimate in the PACG group, compared to both the control and POAG groups.Conclusion: The Smith-method JTSL technique may be used for non-invasive rapid screening, to help identify patients at risk of developing angle-closure, during routine examination of patients in the ophthalmology clinic. [ABSTRACT FROM AUTHOR]

Background: Elevated intraocular pressure (IOP) remained the most important known risk factor for glaucoma. Aim: To compare the postural and diurnal IOP variations using the iCare rebound tonometer (RT) and Perkins applanation tonometer (PAT). Setting: Kakamega County Hospital, Kenya. Methods: Elevated intraocular pressure measurements were taken by two (masked) examiners with two devices in the morning (06:00–09:00), midday (12:00–15:00) and evening (18:00–21:00), in the sitting followed by supine positions in one randomly selected eye of 24 oculo-visual healthy hospital-admitted patients. Effects of the time of the day and position of the body within and between devices were analysed with the Statistical Package for Social Sciences. Results: The mean IOP measured by the RT ranged from 6 mmHg to 24 millimetres of mercury (mmHg) in the sitting position and from 10 mmHg to 26 mmHg in the supine position. The mean IOP measured using PAT ranged from 6 mmHg to 21 mmHg in the sitting position and from 8 mmHg to 24 mmHg in the supine position. The IOP measured by both devices significantly varied with position (p < 0.05). Perkins applanation tonometer on average gave a significantly higher IOP (1.7 mmHg [ p = 0.003] and 1.3 mmHg [ p = 0.034]) at 06:00 compared to that at 12:00 and 18:00, respectively. The IOP readings with the RT were on average 2.2 mmHg and 3.0 mmHg higher at 06:00 compared to that at 12:00 and 18:00, respectively (p < 0.0005). Conclusion: Significant reductions were observed in postural and diurnal IOPs in the sitting positions and in the afternoon, respectively. Diurnal IOP variations were slightly higher when measured by RT compared to when measured by PAT. [ABSTRACT FROM AUTHOR]

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.

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.

Aim: To compare the precision of the Topcon SP-3000P noncontact specular microscope (NCSM) and the DGH 500 ultrasound pachymeter (USP)., Methods: Triplicate measurements of central corneal thickness (CCT) for 100 eyes were taken with an NCSM and a USP in 2 visits separated by 1 week. Repeatability was assessed by computing the differences between all 3 readings from each subject. Coefficients of repeatability and reproducibility were computed., Results: MEAN CCT AS MEASURED BY EACH INSTRUMENT WERE: 518.53 ± 34.96 μm (range 417.33-592.67) and 516.94 ± 33.60 μm (range 431.67-582.67) for sessions 1 and 2 respectively, with the NCSM; 546.69 ± 36.62 μm (range 457.33-617.00) and 549.78 ± 35.26 μm (range 454.00-618.67) for sessions 1 and 2 respectively, with the USP. The ultrasound CCT measurements were consistently higher than those obtained with the NCSM in both sessions 28.17 ± 19.20 μm (mean ± SD, session 1) and 32.81 ± 14.04 (mean ± SD, session 2). The repeatability coefficient for the NCSM was better in both sessions than those for USP (±10 μm vs ± 12 μm in session 1 and ±8 μm vs ±10 μm in session 2). The reproducibility coefficient with the NCSM was half that with the USP (±21 μm vs ±41 μm)., Conclusion: The SP-3000P NCSM is a more precise and reproducible instrument for measurement of CCT than the USP, but both instruments are reliable, useful instruments for measuring CCT.

Purpose: To evaluate the accuracy and reliability of the Keeler Pulsair EasyEye noncontact tonometer in a normotensive population., Methods: This masked prospective clinical study included 72 right eyes of 72 subjects. Two sets of intraocular pressure measurements were made 1 week apart. Intraocular pressure assessment with the Goldmann tonometer was always subsequent to that with the noncontact tonometer. Each method was assessed for within-session and test-retest repeatability and both methods were assessed for limits of agreement, twice. The level of significance for this study was 0.05., Results: Both methods were repeatable within-sessions to within +/-2 mm Hg, and between sessions to within +/-3 mm Hg. Neither the within-session differences nor the between session differences differed significantly between the Goldmann tonometer and the Pulsair EasyEye noncontact tonometer. The mean differences (+/-SD) between both methods (0.1 +/- 1.6 mm Hg and 0.05 +/- 1.7 mm Hg, for the first and second sessions, respectively) were not statistically significant, but the intraocular pressure measured with the Pulsair EasyEye tonometer was consistently higher than that measured with the Goldmann tonometer., Conclusions: The Pulsair EasyEye noncontact tonometer is considered an accurate reliable method in the normotensive population studied but because of a systematic bias in a small number of subjects, it cannot be used interchangeably with the Goldmann tonometer.

Purpose: To determine the limits of agreement between central corneal thickness (CCT) measurements made with the slit lamp-attached optical pachymeter and the SP2000P noncontact specular microscope., Methods: Triplicate readings for CCT were obtained for each of 130 (right) eyes of 130 patients, using the slit lamp-attached optical pachymeter and then the SP2000P noncontact specular microscope. The average CCT measured by each method was compared. Subsequently, the mean difference between both sets of measurements was assessed, and the 95% confidence interval (limits of agreement) between both techniques was determined., Results: The mean +/- SD CCT measured by the optical pachymeter was 543 +/- 34 microm and 532 +/- 34 microm for the specular microscope. We found a statistically significant (P < 0.001) mean bias of 10 mum between CCT values measured with both types of equipment, with the optical pachymeter returning the higher values. The coefficient of variation was 6.3% for the optical pachymeter and 6.4% for the specular microscope., Conclusions: The right eye CCT measurements made by the optical pachymeter are, on average, 10 mum thicker than those made with the SP2000P specular microscope, which suggests that both pieces of equipment cannot be used interchangeably to monitor CCT changes in patients. Excluding left eye measurements, the reliability of the optical pachymeter is identical to that of the noncontact specular microscope.