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Diffusion‐weighted imaging (DWI) is an established functional imaging technique that interrogates the delicate balance of water movement at the cellular level. Technological advances enable this technique to be applied to whole‐body MRI. Theory, b‐value selection, common artifacts and target to background for optimized viewing will be reviewed for applications in the neck, chest, abdomen, and pelvis. Whole‐body imaging with DWI allows novel applications of MRI to aid in evaluation of conditions such as multiple myeloma, lymphoma, and skeletal metastases, while the quantitative nature of this technique permits evaluation of response to therapy. Persisting signal at high b‐values from restricted hypercellular tissue and viscous fluid also permits applications of DWI beyond oncologic imaging. DWI, when used in conjunction with routine imaging, can assist in detecting hemorrhagic degradation products, infection/abscess, and inflammation in colitis, while aiding with discrimination of free fluid and empyema, while limiting the need for intravenous contrast. DWI in conjunction with routine anatomic images provides a platform to improve lesion detection and characterization with findings rivaling other combined anatomic and functional imaging techniques, with the added benefit of no ionizing radiation. J. Magn. Reson. Imaging 2013;38:253–268. © 2013 Wiley Periodicals, Inc.  相似文献   
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NOWELL SOLISH  MD  FRCPC    VINCE BERTUCCI  MD  FRCPC    ALAIN DANSEREAU  MD  FRCPC    H. CHIH-HO HONG  MD  FRCPC    CHARLES LYNDE  MD  FRCPC    MARK LUPIN  MD  FRCPC    KEVIN C. SMITH  MD  FRCPC  FACP    GREG STORWICK  MD  FRCPC 《Dermatologic surgery》2007,33(8):908-923
BACKGROUND: Hyperhidrosis can have profound effects on a patient's quality of life. Current treatment guidelines ignore disease severity. OBJECTIVE: The objective was to establish clinical guidelines for the recognition, diagnosis, and treatment of primary focal hyperhidrosis. METHODS AND MATERIALS: A working group of eight nationally recognized experts was convened to develop the consensus statement using an evidence-based approach. RECOMMENDATIONS: An algorithm was designed to consider both disease severity and location. The Hyperhidrosis Disease Severity Scale (HDSS) provides a qualitative measure that allows tailoring of treatment. Mild axillary, palmar, and plantar hyperhidrosis (HDSS score of 2) should initially be treated with topical aluminum chloride (AC). If the patient fails to respond to AC therapy, botulinum toxin A (BTX-A; axillae, palms, soles) and iontophoresis (palms, soles) should be the second-line therapy. In severe cases of axillary, palmar, and plantar hyperhidrosis (HDSS score of 3 or 4), both BTX-A and topical AC are first-line therapy. Iontophoresis is also first-line therapy for palmar and plantar hyperhidrosis. Craniofacial hyperhidrosis should be treated with oral medications, BTX-A, or topical AC as first-line therapy. Local surgery (axillary) and endoscopic thoracic sympathectomy (palms and soles) should only be considered after failure of all other treatment options. CONCLUSIONS: These guidelines offer a rapid method to assess disease severity and to treat primary focal hyperhidrosis according to severity.  相似文献   
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INTRODUCTION: Monopolar radiofrequency is an effective means of nonsurgical facial skin tightening. OBJECTIVE: The objective of this study was to determine whether using larger tips at lower energy and multiple passes, using patient feedback on heat sensation and treating to a clinical end point of visible tightening, would yield better results than single passes with small tips at high energy, as measured by patient and physician satisfaction. METHODS: Fourteen physicians from four specialties were surveyed to determine the answers to the following three questions. (1) Is patient's feedback on heat sensation a valid and preferred method for optimal energy selection? (2) Do multiple passes at moderate energy settings yield substantial and consistent efficacy? (3) Is treating to a clinical end point of visible tightening predictable of results? RESULTS: A total of 5,700 patient treatments were surveyed. Comparisons were made using the original algorithm of high-energy, single pass to the new algorithm of lower energy and multiple passes with visible tightening as the end point of treatment. Using the original treatment algorithm, 26% of patients demonstrated immediate tightening, 54% observed skin tightening 6 months after treatment, 45% found the procedure too painful, and 68% of patients found the treatment results met their expectations. With the new multiple-pass algorithm, 87% observed immediate tightening, 92% had the tightening six months after treatment, 5% found the procedure too painful, while 94% found the treatment results met their expectations. CONCLUSIONS: Patient feedback on heat sensation is a valid, preferable method for optimal energy selection in monopolar radiofrequency skin-tightening treatments.  相似文献   
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PURPOSE: The objective of this survey was to examine the services offered by multidisciplinary pain treatment facilities (MPTFs) across Canada and to compare access to care at these MPTFs. METHODS: A MPTF was defined as a clinic that advertised specialized multidisciplinary services for the diagnosis and management of patients with chronic pain, having a minimum of three different health care disciplines (including at least one medical speciality) available and integrated within the facility. The search method included approaching all hospital and rehabilitation centre administrators in Canada, the Insurance Bureau of Canada, the Workplace Safety and Insurance Board or similar body in each province. Designated investigators were responsible for confirming and supplementing MPTFs from the preliminary list for each province. Administrative leads at each eligible MPTF were asked to complete a detailed questionnaire regarding their MPTF infrastructure, clinical, research, teaching and administrative activities. RESULTS: Completed survey forms were received from 102 MPTFs (response rate 85%) with 80% concentrated in major cities, and none in Prince Edward Island and the Territories. The MPTFs offer a wide variety of treatments including non-pharmacological modalities such as interventional, physical and psychological therapy. The median wait time for a first appointment in public MPTFs is six months, which is approximately 12 times longer than non-public MPTFs. Eighteen pain fellowship programs exist in Canadian MPTFs and 64% engage in some form of research activities CONCLUSION: Canadian MPTFs are unable to meet clinical demands of patients suffering from chronic pain, both in terms of regional accessibility and reasonable wait time for patients' first appointment.  相似文献   
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Deep brain stimulation (DBS) is a well‐established treatment option for movement disorders, especially for Parkinson's disease (PD). There is a need to determine the role of expectation of benefit and the use of placebo to better understand the effects of electrode placement including the (micro)lesion effect. These factors must be understood to better interpret and attribute the therapeutic value of DBS. In this review, we critically present currently available data on the placebo, nocebo, lessebo, and lesion effects in the context of DBS. We provide a discussion of strategies that have the potential for controlling these effects in the setting of future DBS trials. We conclude that there is a need to standardize definitions for nocebo and (micro)lesion effects and that there are intrinsic limitations in defining the effect of expectation of benefit in DBS. These issues will be challenging to overcome especially with current technology and available study designs. New stimulation paradigms, better study designs, and the use of adaptive closed‐loop DBS devices may facilitate a more accurate assessment of the placebo, nocebo, and lessebo effects in future DBS trials. © 2016 International Parkinson and Movement Disorder Society  相似文献   
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Murad Alam  MD    Jeffrey S. Dover  MD  FRCPC    Kenneth A. Arndt  MD 《Dermatologic surgery》2003,29(7):681-685
BACKGROUND. : Pulsed-dye laser treatment has been shown to be highly effective for the treatment of facial telangiectasia. Posttreatment purpura after such treatment has limited patient acceptance of the procedure. OBJECTIVE. : To determine whether purpura-free treatment with recently introduced variable-pulsed pulsed-dye lasers can effectively reduce facial telangiectasia. METHODS. : This was a prospective, randomized, controlled, nonblinded trial. Eleven patients received variable-pulse pulsed-dye laser treatment with and without induction of purpura. Telangiectasia were graded on a "telangiectasia density scale," on which a 1 signified extremely fine, sparsely distributed telangiectasia, and 5 referred to thick, ropelike telangiectasia covering the affected area. For each subject, two areas on either side of the facial midline with equivalent telangiectasia density ratings were randomized to the purpura and purpura-free treatment groups, respectively. All treatments used a 7-mm spot size and a 10-ms pulse duration. The fluence associated with the purpura threshold for each patient was determined in test areas. Purpura-free treatment entailed a fluence 1.0 J/cm2 less than the purpura threshold, and purpura-level treatment entailed a fluence 0.5 J/cm2 greater than the threshold. RESULTS. : Six weeks after a single purpura-free treatment, mean telangiectasia ratings were reduced from 2.7 to 2.4. Purpura-level treatments resulted in a decrease to 1.4 from the same baseline. Thicker, denser telangiectasia appeared to benefit more from purpura-level treatment (a mean telangiectasia density scale reduction of 1.7) than finer, sparser telangiectasia (a mean reduction of 0.8). In 81% of cases, both investigators and patients rated the side treated with purpura as undergoing a greater reduction in telangiectasia density. CONCLUSION. : Although facial telangiectasia do improve after a single purpura-free treatment with the variable-pulse pulsed-dye laser, they improve more after purpura is induced. Purpura-free and purpura-level treatments may be close to equivalent for treating fine telangiectasia, but purpura-level treatments have a distinct advantage for treating thicker telangiectasia. Significantly, the variable-pulse pulsed-dye laser offers patients the option of effective treatment of some telangiectasia without bruising.  相似文献   
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The os calcis is the most frequently fractured tarsal bone. In 1992 Sanders developed a classification system based on coronal and axial computed tomography (CT) scans of the calcaneus. This classification is the one used most frequently today in treatment decision making and reporting of results. The objective of this study was to assess the degree of interobserver variability in using this classification system. Thirty CTs of calcaneal fractures were chosen randomly from the past 5 years in 2 tertiary care centers. The CTs were reviewed by 3 orthopedic surgeons and one senior orthopedic resident who classified the fractures according to Sanders' classification. The results were first tabulated and analyzed by using a weighted kappa test including the subcategories. The weighted kappa value achieved was.56, with a 95% confidence interval of.45-.67. The subcategories of the classification were then further combined and a second weighted kappa test was performed to assess agreement between general classes. The weighted kappa value achieved was.48, with a 95% confidence interval of 0.37-0.59. We concluded that Sanders' classification system did prove to achieve moderate agreement among users, thus representing a useful classification system.  相似文献   
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