Detection of Neovascularization Based on Fractal and Texture Analysis with Interaction Effects in Diabetic Retinopathy

Diabetic retinopathy is a major cause of blindness. Proliferative diabetic retinopathy is a result of severe vascular complication and is visible as neovascularization of the retina. Automatic detection of such new vessels would be useful for the severity grading of diabetic retinopathy, and it is an important part of screening process to identify those who may require immediate treatment for their diabetic retinopathy. We proposed a novel new vessels detection method including statistical texture analysis (STA), high order spectrum analysis (HOS), fractal analysis (FA), and most importantly we have shown that by incorporating their associated interactions the accuracy of new vessels detection can be greatly improved. To assess its performance, the sensitivity, specificity and accuracy (AUC) are obtained. They are 96.3%, 99.1% and 98.5% (99.3%), respectively. It is found that the proposed method can improve the accuracy of new vessels detection significantly over previous methods. The algorithm can be automated and is valuable to detect relatively severe cases of diabetic retinopathy among diabetes patients.published_or_final_versio

Incidence and Risk Factors for Retinopathy of Prematurity in Multiple Gestations: a Chinese population study

To determine the incidence and risk factors of retinopathy of prematurity (ROP) among new-born Chinese infants of multiple gestations. A retrospective review of medical records was performed for all neonates of multiple gestations screened for ROP between January 2007 and December 2012 in 2 neonatal intensive care units in Hong Kong. Screening was offered to very low birth weight (VLBW; ≤1500g) and/or preterm (gestation ≤32 weeks) neonates using the Royal College of Ophthalmologists ROP guideline and the International Classification of ROP by 3 pediatric ophthalmologists. Maternal and neonatal covariates were analyzed using univariate and multivariate regression analyses for both ROP and Type 1 ROP. A total of 153 Chinese infants of multiple gestations were included in the study. The mean gestational age (GA) was 30.8±2.4 weeks and the mean birth weight (BW) was 1284.8±267.4g. The incidence of ROP and Type 1 ROP was 11.8% and 3.9%, respectively. On univariate analysis, younger GA, lighter birth weight, postnatal hypotension, inotropes use, bronchopulmonary disease, and intraventricular hemorrhage were common independent risk factors for the development of ROP and Type 1 ROP (all P≤0.04). On multivariate analysis, younger GA, surfactant use, invasive mechanical ventilation, higher mean oxygen concentration, thrombocytopenia, intraventricular hemorrahage, total parental nutrition, and hypoglycemia were significant risk factors for ROP. For Type 1 ROP, there were no significant dependent risk factors. In preterm Chinese infants born from multiple gestations, prematurity, lighter weight, postnatal hypotension, inotropes use, bronchopulmonary dysplasia, and an intraventricular hemorrhage were common independent risk factors for the development of ROP and Type 1 ROP.published_or_final_versio

Differences in risk factors for retinopathy of prematurity development in paired twins: A Chinese population study

2014-2015 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Evaluation of an automated immunochemical faecal occult blood test for colorectal neoplasia screening in a Chinese population

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Drug audit in Hong Kong with special reference to antibiotics

In Hong Kong, antibiotic orientated audits have been conducted with respect to (1) the use of paediatric tetracyclines, and (2) ward usage of expensive antibiotics. Consistent with the very high local prevalence of discolouration in the secondary dentition among young persons in the early 1980s, the use of paediatric tetracyclines (sales of liquid formulations) was more than ten-fold greater than the corresponding usage in the UK (inferred from retail prescription surveys). With educational efforts and feedback of such data to doctors, follow-up audits confirm a dramatic reduction in such use of tetracyclines in Hong Kong. A one-month audit of expensive antibiotic administration and dispensing in a single medical ward of Queen Mary Hospital revealed that: (a) much larger amounts of β-lactams were dispensed than administered to patients, and (b) the amount of Unasyn® being given intravenously was probably excessive, considering the good oral bioavailability of this pro-drug. Possible reasons for these anomalies, their expenditure implications and appropriate steps to correct them are discussed.link_to_subscribed_fulltex

Evaluation of five commercial serological tests for the detection of Helicobacter pylori infection in Chinese

Background: Commercial serological tests for the detection of Helicobacter pylori infection must be locally validated. We evaluated the accuracy of five commercial tests in the Chinese population. Methods: Serum samples were collected from patients referred for upper endoscopy. Antral biopsies were taken for histological examination and culture of H. pylori. The gold standard for diagnosing H. pylori infection was positive histological staining and/or positive H. pylori culture. The serum samples were tested for H. pylori antibodies using the following tests: (i) Cobas Core Anti-H. pylori EIA: (ii) GAP IgG; (iii) GAP IgM; (iv) H. pylori microwell EIA (Quidel): and (v) Premier H. pylori. The sensitivity, specificity and accuracy of each test was calculated according to the manufacturers' instructions or according to a new cut-off value. Results: A total of 158 patients were recruited amongst whom 114 (72%) were H. pylori-positive. Indeterminate results varied from 7% to 19%. The accuracy of the tests varied from 57% to 85%. By using new cut-off values, the accuracy was much improved, ranging from 73.4:% to 86.7%. Conclusions: By defining new cut-off values for the Chinese population, we were able to improve the performance of some of the serology tests. This illustrates the importance of local validation.link_to_OA_fulltex

Cetuximab beyond progression in Kras wild-type metastatic colorectal cancer

Posters: P-0254BACKGROUND: Cetuximab and bevacizumab have proven efficacy in the treatment of metastatic colorectal cancer (mCRC). Although new agents such as panitumumab, aflibercept and regorafenib emerge with modest clinical benefit, they are still not widely available. With limited options of target therapy, treatment with individual agent beyond progression is an attractive strategy and use of bevacizumab in this setting has been shown to improve survival. However, evidence for applying the same strategy to cetuximab is not clear. We performed a retrospective analysis to evaluate the clinical benefit of cetuximab beyond progression in Kras wild-typ…link_to_OA_fulltex