Evaluation of retinal vascular caliber in Malay children

Background: Digital retinal vessel imaging is evolving as a non-invasive method of evaluating the microvasculature. In children, the general absence of disease-related confounding factors makes them an ideal study population. However, childhood studies in this field are limited, especially among Malays, the main ethnicity in South East Asia. The present study aims to evaluate the influence of ocular and systemic factors on retinal vessel caliber in a childhood Malay population. Methods: This was a cross-sectional study involving 86 Malay children aged 6 to 12 years old in Hospital Universiti Sains Malaysia, Malaysia. Ocular examination, refraction, retinal photography and axial length were performed by standardized protocols. Anthropometric measurements including blood pressure were likewise obtained. Retinal vessel diameters were summarized as the central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) using validated computerbased methods. Multiple linear regression was used to determine the effect of systemic and ocular biometry on CRAE and CRVE. Results: After correcting for ocular magnification, the mean CRAE and CRVE were 171.40 um and 248.02 um respectively. Blood pressure (SBP, DBP, MAP) and axial length were the main factors affecting the CRAE. After multivariable adjustment, each unit (1 mm Hg) increase in mean arterial pressure was associated with a 0.451 um reduction in CRAE (p=0.013). Each 1 mm increase in axial length was associated with a 4.582 um narrowing of CRAE (p=0.024). All variables analyzed in our study had no statistically significant effect on the CRVE. Conclusion: The mean retinal CRAE and CRVE in Malay children were 171.40 um and 248.02 um. Retinal arteriolar calibers are narrower in healthy children with higher blood pressure and longer axial lengths. These associations suggest that the pathological changes in the microvasculature seen hypertension and pathological myopia may be an amplification of the normal physiological response of blood vessels to various systemic and ocular dynamics

Syringomyelia presenting with unilateral optic neuropathy: a case report

Purpose: In this case report, we present two cases of syringomyelia with optic neuropathy. Findings: In Case 1, a 36-year-old Malay lady presented to our clinic with acute onset of blurring of vision in her left eye that she experienced since past 1 month. She was diagnosed with syringomyelia 12 years ago and was on conservative management. Her visual acuity was 6/6 in the right eye and counting fingers at 1 m in the left. There was a positive relative afferent pupillary defect in her left eye. Optic nerve functions of her left eye were reduced. Visual field showed a left inferior field defect. Her extraocular muscle movements were full. Magnetic resonance imaging of the brain and spine showed syringomyelia at the level of C2–C6 and T2–T9. Both of her optic nerves were normal. Her condition improved with intravenous and oral corticosteroids. In Case 2, a 44-year-old Malay lady presented to our clinic with a progressive central scotoma in her right eye that she experienced since past 1 month. She had previous history of recurrent episodes of weakness in both of her lower limbs from past 8 months. Visual acuity in her right and left eye was 6/9 and 6/6, respectively. The relative afferent pupillary defect in her right eye was positive. Optic nerve functions of her right eye were affected. Visual field showed a central scotoma in her right eye. Her extraocular muscle movements were full. Fundoscopy of her right eye showed a pale optic disc. Her left eye fundus was normal. Magnetic resonance imaging of the brain and spine showed syringomyelia at T3–T6. Both of her optic nerves were normal. A diagnosis of syringomyelia with right optic atrophy was performed. Her condition improved with intravenous and oral corticosteroids. Conclusion: Optic neuropathy is a rare neuro-ophthalmic manifestation in patients with syringomyelia. Prompt diagnosis and timely management are essential to avoid a poor visual outcome. Intravenous corticosteroids are beneficial in the treatment of early optic neuropathy in syringomyelia

Visual electrophy siological tests in obstructive sleep apnoea

AIM:To compare the pattern electroretinogram (PERG) and pattern visual evoked potential ( PVEP ) between obstructive sleep apnoea (OSA) patients and controls. METHODS: This was a prospective cross - sectional study involving 40 OSA patients and 31 control subjects in Hospital Universiti Sains Malaysia. Patients with a confirmed diagnosis of OSA who had no ocular pathology were randomly selected to participate in the study. The apnoea-hypopnoea index (AHI) was obtained from their records and used for stratification of OSA severity. Electrophysiological tests ( PVEP and PERG ) were performed on each patient by a trained technician in the electrophysiology laboratory of the Department of Ophthalmology, USM. The results obtained were recorded as median values. Data analysis was done using IBM Statistics Version 21. 0. RESULTS: Among OSA patients, we observed a significant reduction of the PERG amplitude P50 ( P < 0.001) and the PVEP amplitude P100 (P<0. 001) compared to the control group. OSA patients also had a significant increase in PVEP time to peak P100 (P = 0. 003) and time to peak N75 (P = 0. 004). However, no significant differences were detected in PERG time to peak between OSA patients and controls. There were likewise no significant differences in PVEP or PERG between OSA patients with different disease severity. CONCLUSION: OSA patients have significant abnormalities in PVEP amplitude and time to peak, as well as PERG amplitude. This may reflect subclinical optic nerve dysfunction in OSA. Further research is needed to determine the association between the severity of OSA and the degree of optic nerve dysfunction

Psychometric properties of the health-promoting lifestyle profile II: cross-cultural validation of the Malay language version

Background: Health-promoting behaviour is an important concept for health education. Unfortunately, there is a dearth of validated instruments to measure levels of health-promoting behaviour in the Malaysian context. The purpose of this study was to validate a Malay-language version of the Health-Promoting Lifestyle Profile II (HPLP-II) using a confirmatory approach. Methods: Participants were 997 university undergraduate students, with a mean age of 21 years (SD = 1.58). The majority of the participants (80.4%) were female. Health-promoting behaviour was assessed using the 52-item HPLP-II, which measures six components of health-promoting behaviour outcomes. HPLP-II was translated into the Malay language using standard forward and backward translation procedures. Participants then completed the HPLP-II Malay version (HPLP-II-M). Confirmatory factor analysis (CFA) was conducted using Mplus 8.0 software on the six domains of HPLP-II-M model. Results: The CFA result based on the hypothesised measurement model of six factors was aligned with the original HPLP-II, except for two low loading items which were subsequently removed from the CFA analysis. The final CFA measurement model with 50 items resulted in a good fit to the data based on RMSEA and SRMR fit indices (RMSEA = 0.046, 90%CI = 0.045, 0.048, SRMR = 0.062). The construct reliabilities for the HPLP-II-M subscales were acceptable, ranging from 0.737 to 0.878. Conclusion: The HPLP-II-M with six components of health-promoting behaviour outcomes and 50 items was considered valid and reliable for the present Malaysian sample.Research University Individual, Universiti Sains Malaysia (1001/PPSP/8012250

Effect of stenting and mucosal flap preservation on outcome of endoscopic dacryocystorhinostomy

AIM: To determine the effect of stenting and flap preservation on the outcome of endoscopic dacryocystorhinostomy. METHODS: Retrospective study of all endoscopic dacryocystorhinostomy cases performed between 2007 - 2011 at Hospital Universiti Sains Malaysia. A total of 25 cases with nasolacrimal duct obstruction underwent this procedure. Outcome of endoscopic dacryocystorhinostomy was evaluated based on relief of epiphora and anatomical patency by lacrimal syringing and nasal endoscopy upon follow-up at 1, 6 and 12 months post- op. The outcome was considered to be successful only if all three criteria were fulfilled at one year follow - up post - op. Multiple logistic regression was used to determine the association of stenting and flap creation with a successful outcome. RESULTS: Stents were inserted in 13 cases out of 25, and likewise for flaps. The success rate of endoscopic dacryocystorhinostomy at one year post - op was 64% . There was no significant association of stenting with outcome (P = 0. 694), whereas mucosal flap creation was significantly associated with a better outcome (adjusted OR= 7.926; 95%CI: 1. 172-53. 620, P = 0. 034). The main postoperative complication was adhesions, which occurred in 50% of cases. There was no significant association between stenting or flap preservation with complications. CONCLUSION: Preservation of a mucosal flap is significantly associated with a successful outcome of endoscopic dacryocystorhinostomy in nasolacrimal duct obstruction, while stenting is not. Neither stenting nor mucosal flap creation is significantly associated with complications

Factors predicting visual improvement post pars plana vitrectomy for proliferative diabetic retinopathy

誗AIM: To identify factors predicting visual improvement post vitrectomy for sequelae of proliferative diabetic retinopathy (PDR). 誗METHODS: This was a retrospective analysis of pars plana vitrectomy indicated for sequelae of PDR from Jan. to Dec. 2014 in Hospital Sultanah Bahiyah, Alor Star, Kedah, Malaysia. Data collected included patient demographics, baseline visual acuity ( VA ) and post - operative logMAR best corrected VA at 1y. Data analysis was performed with IBM SPSS Statistics Version 22郾0. 誗RESULTS: A total of 103 patients were included. The mean age was 51郾2y. On multivariable analysis, each preoperative positive deviation of 1 logMAR from a baseline VA of 0 logMAR was associated with a post - operative improvement of 0郾859 logMAR (P < 0郾001). Likewise, an attached macula pre - operatively was associated with a 0郾374 (P = 0郾003) logMAR improvement post vitrectomy. Absence of iris neovascularisation and absence of post - operative complications were associated with a post vitrectomy improvement in logMAR by 1郾126 (P = 0郾001) and 0郾377 ( P = 0郾005 ) respectively. Absence of long - acting intraocular tamponade was associated with a 0郾302 (P = 0郾010) improvement of logMAR post vitrectomy. 誗CONCLUSION: Factors associated with visual improvement after vitrectomy are poor pre-operative VA, an attached macula, absence of iris neovascularisation, absence of post - operative complications and abstaining from use of long - acting intraocular tamponade. A thorough understanding of the factors predicting visual improvement will facilitate decision - making in vitreoretinal surgery

Evaluation of anatomical and visual function for early detection of ethambutol toxicity among tuberculosis patients

AIM: To evaluate if early ethambutol toxicity can be detected by comparing pre - and post - treatment anatomical and visual function using retinal nerve fiber thickness, pattern visual evoked potentials and conventional optic nerve function tests. METHODS:This was a prospective study involving 72 eyes of 36 patients treated with ethambutol according to directly observed treatment short-course(DOTS) strategy in Hospital Universiti Sains Malaysia, Kelantan, Malaysia. The visual acuity and optic nerve function tests were performed by a single investigator. Likewise, Humphrey automated perimetry, optical coherence tomography ( OCT ) measurement of the retinal nerve fibre layer (RNFL) and pattern visual evoked potential (PVEP) were performed by a single technician. The examinations were performed before initiating ethambutol treatment and 3mo after that. RESULTS: There was no change in visual acuity, colour vision, light brightness, red saturation and fundus findings pre and post ethambutol. However, there was a statistically significant deterioration in the mean deviation of the visual field post treatment (P = 0. 010). There were also significant changes on OCT and PVEP, with increased RNFL thickness in all quadrants ( P < 0. 05 ) and PVEP delayed P100 peak latency and amplitude (P<0. 001). CONCLUSION: Ethambutol toxicity is a known complication of tuberculosis treatment. Early detection of this toxicity may prevent severe irreversible visual loss. The use of OCT to detect RNFL thickness and PVEP to assess P100 latency and amplitude can assist in the detection of subclinical anatomical and visual function changes prior to development of abnormalities on conventional optic nerve function tests

Concurrent hyphema and orbital apex syndrome following herpeszoster ophthalmicus in a middle aged lady

INTRODUCTION: Hyphema and orbital apex syndrome occurring concurrently in a patient with herpeszoster ophthalmicus have not been reported previously. We present a case with these unique findingsand discuss the pathogenesis of these conditions and their management.PRESENTATION OF CASE: A 59-year-old Malay lady with underlying diabetes mellitus presented withmanifestations of zoster ophthalmicus in the left eye. Two weeks later, she developed total hyphema,and complete ophthalmoplegia suggestive of orbital apex syndrome. She was treated with combinationof intravenous acyclovir and oral corticosteroids, and regained full recovery of ocular motility. Totalhyphema persisted, and she required surgical intervention.DISCUSSION: Hyphema is postulated to occur due to an immune vasculitis affecting the iris vessels. Orbitalapex syndrome is probably due to an occlusive vasculitis affecting the vasculature of the extraocular mus-cles and optic nerve, resulting from a direct invasion by varicella zoster virus or infiltration of perivascularinflammatory cells. Magnetic Resonance Imaging of the brain is essential to exclude possibility of localcauses at the orbital apex area.CONCLUSION: Herpes zoster ophthalmicus is an uncommon ocular presentation. Managing two concur-rent complications; persistent total hyphema and orbital apex syndrome is a challenging clinical situation.Early diagnosis and prompt treatment are essential to prevent potential blinding situation

Concurrent hyphema and orbital apex syndrome following herpeszoster ophthalmicus in a middle aged lady

INTRODUCTION: Hyphema and orbital apex syndrome occurring concurrently in a patient with herpes zoster ophthalmicus have not been reported previously. We present a case with these unique findings and discuss the pathogenesis of these conditions and their management. PRESENTATION OF CASE: A 59-year-old Malay lady with underlying diabetes mellitus presented with manifestations of zoster ophthalmicus in the left eye. Two weeks later, she developed total hyphema,and complete ophthalmoplegia suggestive of orbital apex syndrome. She was treated with combinationof intravenous acyclovir and oral corticosteroids, and regained full recovery of ocular motility. Totalhyphema persisted, and she required surgical intervention. DISCUSSION: Hyphema is postulated to occur due to an immune vasculitis affecting the iris vessels. Orbitalapex syndrome is probably due to an occlusive vasculitis affecting the vasculature of the extraocular muscles and optic nerve, resulting from a direct invasion by varicella zoster virus or infiltration of perivascularinflammatory cells. Magnetic Resonance Imaging of the brain is essential to exclude possibility of localcauses at the orbital apex area. CONCLUSION: Herpes zoster ophthalmicus is an uncommon ocular presentation. Managing two concur-rent complications; persistent total hyphema and orbital apex syndrome is a challenging clinical situation.Early diagnosis and prompt treatment are essential to prevent potential blinding situation

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe