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Yam J.C.S.,Chinese University of Hong Kong | Kwok A.K.H.,Hong Kong Sanatorium and Hospital
International Ophthalmology

The objective of this study is to review the association between ultraviolet (UV) light and ocular diseases. The data are sourced from the literature search of Medline up to Nov 2012, and the extracted data from original articles, review papers, and book chapters were reviewed. There is a strong evidence that ultraviolet radiation (UVR) exposure is associated with the formation of eyelid malignancies [basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)], photokeratitis, climatic droplet keratopathy (CDK), pterygium, and cortical cataract. However, the evidence of the association between UV exposure and development of pinguecula, nuclear and posterior subcapsular cataract, ocular surface squamous neoplasia (OSSN), and ocular melanoma remained limited. There is insufficient evidence to determine whether age-related macular degeneration (AMD) is related to UV exposure. It is now suggested that AMD is probably related to visible radiation especially blue light, rather than UV exposure. From the results, it was concluded that eyelid malignancies (BCC and SCC), photokeratitis, CDK, pterygium, and cortical cataract are strongly associated with UVR exposure. Evidence of the association between UV exposure and development of pinguecula, nuclear and posterior subcapsular cataract, OSSN, and ocular melanoma remained limited. There is insufficient evidence to determine whether AMD is related to UV exposure. Simple behaviural changes, appropriate clothing, wearing hats, and UV blocking spectacles, sunglasses or contact lens are effective measures for UV protection. © 2013 Springer Science+Business Media Dordrecht. Source

Wan T.S.K.,University of Hong Kong | Ma E.S.K.,Hong Kong Sanatorium and Hospital
Chang Gung Medical Journal

Cytogenetic aberrations may escape detection or recognition in traditional karyotyping. The past decade has seen an explosion of methodological advances in molecular cytogenetics technology. These cytogenetics techniques add color to the black and white world of conventional banding. Fluorescence in-situ hybridization (FISH) study has emerged as an indispensable tool for both basic and clinical research, as well as diagnostics, in leukemia and cancers. FISH can be used to identify chromosomal abnormalities through fluorescent labeled DNA probes that target specific DNA sequences. Subsequently, FISH-based tests such as multicolor karyotyping, comparative genomic hybridization (CGH) and array CGH have been used in emerging clinical applications as they enable resolution of complex karyotypic aberrations and whole global scanning of genomic imbalances. More recently, cross species array CGH analysis has also been employed in cancer gene identification. The clinical impact of FISH is pivotal, especially in the diagnosis, prognosis and treatment decisions for hematological diseases, all of which facilitate the practice of personalized medicine. This review summarizes the methodology and current utilization of these FISH techniques in unraveling chromosomal changes and highlights how the field is moving away from conventional methods towards molecular cytogenetics approaches. In addition, the potential of the more recently developed FISH tests in contributing information to genetic abnormalities is illustrated. Source

Fung W.W.K.,Hong Kong Sanatorium and Hospital | Wu V.W.C.,Hong Kong Polytechnic University | Teo P.M.L.,Central Comprehensive Cancer Center
Medical Dosimetry

Adaptive radiotherapy (ART) has been introduced to correct the radiation-induced anatomic changes in head and neck cases during a treatment course. This study evaluated the potential dosimetric benefits of applying a 3-phase adaptive radiotherapy protocol in nasopharyngeal carcinoma (NPC) patients compared with the nonadaptive single-phase treatment protocol. Ten NPC patients previously treated with this 3-phase radiation protocol using Hi-Art Tomotherapy were recruited. Two new plans, PII-ART and PIII-ART, were generated based on the up-to-date computed tomography (CT) images and contours and were used for treatment in phase two (PII; after 25th fraction) and phase three (PIII; after 35th fraction), respectively. To simulate the situation of no replanning, 2 hybrid plans denoted as PII-NART and PIII-NART were generated using the original contours pasted on the PII- and PIII-CT sets by CT-CT fusion. Dosimetric comparisons were made between the NART plans and the corresponding ART plans. In both PII- and PIII-NART plans, the doses to 95% of all the target volumes (D 95) were increased with better dose uniformity, whereas the organs at risk (OARs) received higher doses compared with the corresponding ART plans. Without replanning, the total dose to 1% of brainstem and spinal cord (D 1) significantly increased 7.87 ± 7.26% and 10.69 ± 6.72%, respectively (P = 0.011 and 0.001, respectively), in which 3 patients would have these structures overdosed when compared with those with two replannings. The total maximum doses to the optic chiasm and pituitary gland and the mean doses to the left and right parotid glands were increased by 10.50 ± 10.51%, 8.59 ± 6.10%, 3.03 ± 4.48%, and 2.24 ± 3.11%, respectively (P = 0.014, 0.003, 0.053, and 0.046, respectively). The 3-phase radiotherapy protocol showed improved dosimetric results to the critical structures while keeping satisfactory target dose coverage, which demonstrated the advantages of ART in helical tomotherapy of NPC. © 2012 American Association of Medical Dosimetrists. Source

Ng D.S.,Tung Wah Eastern Hospital | Kwok A.K.,Hong Kong Sanatorium and Hospital | Chan C.W.,Tung Wah Eastern Hospital
Clinical and Experimental Ophthalmology

Myopic choroidal neovascularization (CNV) is a vision-threatening complication in the eyes with pathological myopia, which is particularly prevalent among young and middle-aged Asians globally. To date, the verteporfin in photodynamic therapy study is the only randomized-controlled study in treatment of subfoveal myopic CNV. However, its long-term benefit is controversial. Recently, intravitreal injections of anti-vascular endothelial growth factors have shown promising results. In the absence of randomized-controlled trial comparing the efficacy of anti-vascular endothelial growth factors with photodynamic therapy and placebo, the purpose of this article is to review the current studies on functional and anatomical outcomes in both subfoveal and juxtafoveal myopic CNV. Furthermore, the influences of various doses and frequencies, as well as age and previous photodynamic therapy treatment on its effect are described. © 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists. Source

Chan S.W.W.,Kowloon East Cluster Breast Center | Chueng P.S.Y.,Hong Kong Sanatorium and Hospital | Lam S.H.,Kowloon East Cluster Breast Center
World Journal of Surgery

Background: Since breast-conserving surgery demonstrated identical long term survival on seven randomized trials, it has become the preferred treatment option over mastectomy. Oncoplastic surgery applying simple reshaping and displacement techniques allows inclusion of patients with large tumors in the group selected for breast-conserving surgery. However, the cosmetic outcome and the degree of patient satisfaction, especially in relation to the original breast volume and the percentage of breast tissue excised is not well documented. Objective: The present study was designed to assess patient satisfaction with cosmetic outcome after oncoplastic breast-conserving surgery, and to establish the correlation between patient satisfaction and percentage of breast volume excision (PBVE). Materials and methods: A total of 169 Asian patients underwent breast-conserving surgery for primary breast cancer at either United Christian Hospital (UCH) or Hong Kong Sanatorium and Hospital (HKSH) from Nov 2007 to Jan 2008 by two breast surgeons. Among this group, 162 patients with breast-conserving surgery incorporating oncoplastic techniques were prospectively recruited for study. Tumor characteristics, patient satisfaction, cosmetic outcome and surgeons' score were prospectively documented. Breast volume (BV) calculation was based on preoperative mammography (BV = 1/3πr1r2h), which was validated by our previous study to correlate strongly with actual BV (r = 0.98). PBVE was calculated by dividing the fresh specimen weight by the calculated BV. A standardized questionnaire was used to assess patient satisfaction and surgeons' score on cosmetic outcome during the first 1-3 postoperative months. The correlation between PBVE and patient satisfaction was studied. Results: The median age of the group of patients studied was 52 years (range: 20-96 years). The median tumor size was 2.5 cm (range: 0.6-5 cm). The median breast volume was 493 cm3 (range: 210-1,588 cm3). The median PBVE was 7.4% (range: 1-42%), and 94% of patients were very satisfied or satisfied with the cosmetic outcome. In addition, 85% of patients felt that the treated breast was nearly identical with or only slightly different from the untreated breast. In scoring breast shape, surgeons indicated that 89% of the treated breasts were identical to or only minimally different from the untreated breast. Patient satisfaction decreased significantly when the PBVE exceeded 20%. Neither tumor location nor distance of the tumor from the nipple had any effect on patient satisfaction. Conclusions: This study showed high patient satisfaction and good cosmetic outcome after oncoplastic breast-conserving surgery, even in small breast sized Asian women. The application of oncoplastic technique allows large volume excision, and satisfaction remains high with breast volume excision less than 20% regardless of tumor location or distance of the tumor from the nipple. More complicated oncoplastic techniques, e.g., breast replacement, might be required if breast volume excision exceeds 20%. © 2009 Société Internationale de Chirurgie. Source

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