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Aim: To study the prevalence of filtration-bleb transconjunctival oozing in the first postoperative year after various glaucoma procedures. Methods: Cross-sectional, single-point examination of all filtration blebs in eyes which had glaucoma surgery in the last year. Eyes were examined 3-12 months after surgery and were grouped into non-penetrating (NPGS) and penetrating (PGS)  相似文献   
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The recalculation of 1 fraction from a patient treatment plan on a phantom and subsequent measurements have become the norms for measurement-based verification, which combines the quality assurance recommendations that deal with the treatment planning system and the beam delivery system. This type of evaluation has prompted attention to measurement equipment and techniques. Ionization chambers are considered the gold standard because of their precision, availability, and relative ease of use. This study evaluates and compares 5 different ionization chambers: phantom combinations for verification in routine patient-specific quality assurance of RapidArc treatments. Fifteen different RapidArc plans conforming to the clinical standards were selected for the study. Verification plans were then created for each treatment plan with different chamber-phantom combinations scanned by computed tomography. This includes Medtec intensity modulated radiation therapy (IMRT) phantom with micro-ionization chamber (0.007 cm3) and pinpoint chamber (0.015 cm3), PTW-Octavius phantom with semiflex chamber (0.125 cm3) and 2D array (0.125 cm3), and indigenously made Circular wax phantom with 0.6 cm3 chamber. The measured isocenter absolute dose was compared with the treatment planning system (TPS) plan. The micro-ionization chamber shows more deviations when compared with semiflex and 0.6 cm3 with a maximum variation of ?4.76%, ?1.49%, and 2.23% for micro-ionization, semiflex, and farmer chambers, respectively. The positive variations indicate that the chamber with larger volume overestimates. Farmer chamber shows higher deviation when compared with 0.125 cm3. In general the deviation was found to be <1% with the semiflex and farmer chambers. A maximum variation of 2% was observed for the 0.007 cm3 ionization chamber, except in a few cases. Pinpoint chamber underestimates the calculated isocenter dose by a maximum of 4.8%. Absolute dose measurements using the semiflex ionization chamber with intermediate volume (0.125 cm3) shows good agreement with the TPS calculated among the detectors used in this study. Positioning is very important when using smaller volume chambers because they are more sensitive to geometrical errors within the treatment fields. It is also suggested to average the dose over the sensitive volume for larger-volume chambers. The ionization chamber-phantom combinations used in this study can be used interchangeably for routine RapidArc patient-specific quality assurance with a satisfactory accuracy for clinical practice.  相似文献   
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The collateral perfusion via the hypertrophied internal thoracic arteries and rich anastomosis between the epigastric arteries reconstituting femoral artery are an important route in patients with peripheral vascular disease (chronic aortoiliac occlusion), providing blood flow to the lower extremities. Selective angiography of the internal thoracic artery plays a major role in the preoperative evaluation in patients with severe aortoiliac occlusive disease undergoing coronary bypass surgery and may prevent a major potential postoperative complication of acute lower extremity ischemia in these patients.  相似文献   
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The XCEDE (XML-based Clinical and Experimental Data Exchange) XML schema, developed by members of the BIRN (Biomedical Informatics Research Network), provides an extensive metadata hierarchy for storing, describing and documenting the data generated by scientific studies. Currently at version 2.0, the XCEDE schema serves as a specification for the exchange of scientific data between databases, analysis tools, and web services. It provides a structured metadata hierarchy, storing information relevant to various aspects of an experiment (project, subject, protocol, etc.). Each hierarchy level also provides for the storage of data provenance information allowing for a traceable record of processing and/or changes to the underlying data. The schema is extensible to support the needs of various data modalities and to express types of data not originally envisioned by the developers. The latest version of the XCEDE schema and manual are available from .  相似文献   
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PURPOSE: The number of very elderly patients waiting for cataract surgery is predicted to increase. The aim of our study was to determine the clinical outcome following cataract surgery in this age group. METHODS: In this retrospective study, patients aged 96 years and above, who underwent cataract surgery between June 1993 and January 2001, were identified. Clinical data were retrieved from their medical records. Living patients were further invited for clinical examination. RESULTS: In all, 34 eyes of 21 patients (20 females) were identified. Six patients were deceased. In total, 30/34 eyes had phacoemulsification and four had extracapsular extraction. Preoperative vision was or=6/60 in 25/34 eyes (73.53%), >or=6/18 in 21/34 eyes (61.76%), and >or=6/9 in 10/34 eyes (29.41%). Visual acuity improved in 24/34 eyes (70.59%) and remained the same in 6/34 eyes. Complications included anterior capsule tear (three), zonular dialysis with vitreous loss (one), posterior capsule rupture with vitreous loss (one), incarceration of iris to paracentesis wound (two), postoperative uveitis (two), and posterior capsular opacification (19). In all, 7/34 eyes had undergone YAG capsulotomy. CONCLUSION: Surgeons should not be deterred from offering cataract surgery to the very elderly as successful visual rehabilitation is the norm. A further prospective multicentre study is required to confirm the benefits and assess the risks of cataract surgery in this age group.  相似文献   
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STUDY DESIGN: Single case report. OBJECTIVE: To report a case of urethral obstruction because of calculus in a subject with spinal cord injury (SCI). SETTING: Bangalore, India. CASE REPORT: A 25-year-old man sustained complete SCI at C(6) level following a road traffic accident. After 14 months, while on self-intermittent catheterization he noticed difficulty in introducing catheter and acute retention of urine. X-ray examination revealed a calculus in the penile urethra at the level of the glans penis. CONCLUSION: Impaction of calculi in penile urethra, although rare, can manifest with acute painless urinary retention in patients with SCI.  相似文献   
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