A survey of first-year biology student opinions regarding live lectures and recorded lectures as learning tools.

A cohort of first-year biology students was surveyed regarding their opinions and viewing habits for live and recorded lectures. Most respondents (87%) attended live lectures as a rule (attenders), with 66% attending more than two-thirds of the lectures. In contrast, only 52% accessed recordings and only 13% viewed more than two-thirds of the available recordings. Respondents regarded lectures as efficient for information delivery (75%), and 89% enjoyed live lectures because they were useful for learning (89%), understanding coursework (94%), and keeping up with the subject (93%). Lecture enjoyment was driven less by entertainment (34%) or interaction with the lecturers (47%), although most students preferred an entertaining lecturer to a factual expert (72%). Exam marks were positively correlated with the number of lectures attended (P < 0.001) and negatively correlated with the number of recordings viewed (P < 0.05), although marks were similar for lecture attenders and nonattenders (P > 0.05). Lecture attenders mostly missed lectures to complete assessments during the same week (68%), whereas nonattenders were more likely to miss lectures due to outside commitments or preference for study from books or recorded lectures (P < 0.001). Recordings were used to replace missed lectures (64%), rather than for revision, and were viewed mostly alone (96%) in one sitting (65%). Only 22% of respondents agreed that some lectures could be replaced by recordings, but 59% agreed with having some videoconference lectures from experts on another campus. Overall, this cohort showed a clear preference for live lectures over recordings, with limited support for synchronous videoconference lectures.

Effect of topical atropine on astigmatism.

AIM: The aim of this study was to determine if topical atropine, used to retard axial length elongation and myopia progression, had any effect on ocular astigmatism. METHODS: Data collected from subjects enrolled in the Atropine in the Treatment of Myopia (ATOM) study were analysed. In this study, 400 myopic children (aged 6-12 years) were randomly assigned to administer atropine 1% or a placebo daily to a randomly selected eye for 2 years. Cycloplegic autorefraction and keratomy readings were measured using a Canon RK5 autorefractor. The refractive error was then split into its power vector components: J0 and J45. RESULTS: Astigmatism increased by 0.12-0.16 D per year in both treated and placebo groups. There was no difference between groups (p = 0.182). The increase was mirrored by an increase in corneal astigmatism of 0.10-0.13 D per year, suggesting that most of the change was corneal in nature. There was an increase in J0 vector (with-the-rule astigmatism) with no change in the J45 (oblique) vector over time. The change in the J0 vector was significantly larger in the atropine-treated versus atropine-untreated eyes during the 2-year treatment period (p = 0.011), but this difference disappeared after atropine was stopped. CONCLUSION: The use of atropine on a daily basis over 2 years did not have any clinically significant effect on astigmatism.

Uncorrected refractive error in Singapore teenagers.

AIM: To study the prevalence rate of uncorrected refractive error and associated risk factors among Singapore schoolchildren aged 12-16 years (grade 7). METHODS: A cross sectional study of 628 participants (participation rate 99.8%) was conducted in two schools. An interviewer led questionnaire asking about sociodemographic variables and risk factors was administered. Refractive errors were measured using a table mounted autorefractor. Participants with habitual visual acuity (VA) of 0.2 logMAR or worse underwent subjective refraction. Uncorrected refractive error was defined as improvement of at least 0.2 logMAR in best corrected visual acuity after subjective refraction. RESULTS: The prevalence rate of uncorrected refractive error was 22.3% (95% confidence interval (CI) 19.0% to 25.5%). The multivariate adjusted odds ratio of uncorrected refractive error in students with the lowest academic ability was 2.24 (95% CI 1.34 to 3.73). Increasing time interval since the last visit to an eye care provider increased the risk of uncorrected refractive error (trend p = 0.001). CONCLUSION: Uncorrected refractive error was a significant problem among Singapore students aged 12-16 years (grade 7). Uncorrected refractive error was more common among students with low academic ability or those who had not visited an eye care provider for a long time.

Eye growth changes in myopic children in Singapore.

AIMS: To assess the longitudinal changes in biometric parameters and associated factors in young myopic children aged 7--9 years followed prospectively in Singapore. METHODS: Children aged 7--9 years from three Singapore schools were invited to participate in the SCORM (Singapore Cohort study Of the Risk factors for Myopia) study. Yearly eye examinations involving biometry measures were performed in the schools. Only myopic children (n=543) with 3 year follow up data were included in this analysis. RESULTS: The 3 year increases in axial length, anterior chamber depth, lens thickness, vitreous chamber depth, and corneal curvature were 0.89 mm, -0.02 mm, -0.01 mm, 0.92 mm, and 0.01 mm, respectively. Children who were younger, female, and who had a parental history of myopia were more likely to have greater increases in axial length. After adjustment for school, age, sex, race, parental myopia and reading in books per week, the age (p<0.001), sex (p=0.012), and parental myopia (p=0.027) remained significantly associated with the 3 year change in axial length. Reading in books per week, however, was not associated with axial length change. Children with faster rates of progression of myopia had greater increases in axial length (Pearson correlation coefficient (r)=-0.69) and vitreous chamber depth (r=-0.83). CONCLUSIONS: The 3 year change in axial length of Singapore children aged 7--9 years at baseline was high and greater in younger children, females, and children with a parental history of myopia. Myopia progression was driven largely by vitreous chamber depth increase.

Myopia and night lighting in children in Singapore.

AIM: To examine the role of night time lighting and myopia in children in Singapore METHODS: A cross sectional study was conducted on 1001 children in two Singapore schools. Cycloplegic refraction and A-scan biometry measurements were made in both eyes. A detailed questionnaire was completed by the parents to obtain information on night time lighting, near work activity, educational and demographic factors. RESULTS: There was no difference in myopia prevalence rates in children exposed to night time light (33.1%) compared with children who slept in the dark (31.4%) before age 2. In addition, vitreous chamber depth was not related to night light (p = 0.58) before age 2. These results remained even after controlling for near work. CONCLUSION: Myopia is not associated with night light in Asian populations.

Myopia: gene-environment interaction.

INTRODUCTION: Myopia has reached epidemic proportions in Japan, Hong Kong, Taiwan and Singapore. This review summarises the evidence for environmental and genetic factors as well as gene-environment interaction for myopia for both epidemiologic studies as well as animal models. METHODS: A literature review was conducted after a Medline search on articles on the genetic or environmental aetiology of myopia in animal or epidemiologic studies. Articles on the methodology of gene-environment studies were also reviewed. All articles reviewed were articles published in peer-reviewed journals. RESULTS: Cross-sectional studies have found a positive association between myopia and near work activity such as reading and writing. Likewise, laboratory research has shown that environmental factors such as visual deprivation may lead to the development of myopia in animals. While linkage studies in humans are currently being conducted to identify possible markers for myopia in the human genome, several neurotransmitters, modulators and growth factors that influence refractive development have already been identified in animal models that may help identify candidate genes. Epidemiologic studies have also evaluated the combined effects of hereditary factors, environmental factors and gene-environment interaction on myopia development. CONCLUSIONS: Both genes and environmental factors may be related to myopia. There are no conclusive studies at present, however, that identify the nature and extent of possible gene-environment interaction. Further linkage analysis, affected sib-pair studies, and family-based association studies may better identify the nature of gene-environment interaction.

The surgical anatomy of thoracic facet denervation.

Thoracic percutaneous facet denervation has been employed for the treatment of thoracic zygapophysial joint pain. But the surgical anatomy of this procedure has been assumed to be the same as for lumbar medial branch neurotomy. To establish the anatomical basis for thoracic medial branch neurotomy, an anatomical study was undertaken. Using an X40 dissecting microscope, a total of 84 medial branches from 7 sides of 4 embalmed human adult cadavers were studied. The medial branches of the thoracic dorsal rami were found to assume a reasonably constant course. Upon leaving the intertransverse space, they typically crossed the superolateral corners of the transverse processes and then passed medially and inferiorly across the posterior surfaces of the transverse processes before ramifying into the multifidus muscles. Exceptions to this pattern occurred at mid-thoracic levels (T5-T8). Although the curved course remained essentially the same, the inflection occurred at a point superior to the superolateral corner of the transverse process. At no time during the dissection were nerves encountered crossing the junctions between the superior articular processes and transverse processes which have been the target points advocated for thoracic facet denervation. Rather, the results of this study indicate that the superolateral corners of the transverse processes are more accurate target points.