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Mammographic calcification is an important radiologic feature of early breast carcinoma whose index of suspicion for malignancy may be reported by a five‐tier R‐category system. This study aims to describe the histologic diagnoses underlying screen‐detected mammographic calcifications using both digital and screen‐film mammography, and to correlate these findings with radiologic R‐categories. Patients attending the Merrion Breast Screening Unit in Dublin between 2000 and 2011 were identified, who underwent needle‐core biopsy for assessment of mammographic calcifications without associated mass or architectural distortion. Radiologic R‐category was correlated with biopsy and excision histology reports. A total of 776 cases of calcification were identified, involving 769 individual patients. The radiologic R‐categories were as follows: R3 513 (66.1%), R4 192 (24.7%), R5 71 (9.1%). The positive predictive values for malignancy were R3 32.6%, R4 69.8%, R5 95.8%. Several histologic features of DCIS were associated with R5 rather than R3 radiology: high nuclear grade, solid or cribriform architecture, necrosis, periductal inflammation or fibrosis, and associated microinvasive or invasive carcinoma. Mammographic lesions and histologic whole and invasive tumors increased in size from R3 to R5. Radiologic size of calcifications correlated with whole (but not invasive) tumor size, although it tended to underestimate it by several millimeters. Digital‐detected calcifications were more likely than screen‐film detected to be categorized as R3 and less likely R4 or R5, and there was no significant difference in positive predictive value between the two imaging techniques in any R‐category. In conclusion, histologic features of DCIS, in particular those associated with high grade, are associated with R5 radiology. There is no significant difference in positive predictive value for malignancy in any R‐category between digital and screen‐film mammography.  相似文献   
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Introduction: Pacemakers and implantable cardioverter-defibrillators (ICDs) are vulnerable to inappropriate sensing of electromagnetic interference (EMI), such as from nerve conduction studies. We conducted a prospective study to assess the safety of repetitive nerve stimulation (RNS). Methods: Fourteen patients undergoing insertion of 10 ICDs and 4 pacemakers under general anesthesia received RNS of the median, axillary, and spinal accessory nerves at 2 HZ and 50 HZ . We recorded detection of EMI and whether or not this resulted in an arrhythmia diagnosis or change in pacing output. Results: EMI was visible in 2 ICDs, without spurious tachyarrhythmia detection. EMI was observed in 3 of the 4 pacemakers, which led to pacing inhibition and a pause in 2, both of which were programmed to a unipolar sensing configuration. Conclusions: RNS is safe in patients with ICDs. In pacemaker patients, RNS appears safe during bipolar sensing, but caution is recommended in pacemaker patients with unipolar sensing. Muscle Nerve 47: 840–844, 2013  相似文献   
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Introduction: Nerve entrapment due to osseous callus formation is a rare complication after bone fracture. Electrodiagnostic studies and routine radiographic imaging often fail to demonstrate the pathology. The diagnosis is difficult and is often made incidentally upon surgical exploration. Nerve ultrasonography has not been used routinely to assess such lesions. Methods: We report 5 cases of nerve entrapment in osseous callus after fractures that occurred in 2011 and 2012. The diagnosis was made by ultrasound (US). We then performed a review of the relevant literature. Conclusions: US is becoming an invaluable tool for diagnosing peripheral nerve entrapments. The current cases suggest that nerve US should be strongly considered as an adjunctive diagnostic tool for nerve palsies developing after trauma. Muscle Nerve 48 : 445–450, 2013  相似文献   
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Treatment effect in Huntington disease (HD) clinical trials has relied on primary outcome measures such as total motor score or functional rating scales. However, these measures have limited sensitivity, particularly in pre‐ to early stages of the disease. We performed a systematic review of HD clinical studies to identify endpoints that correlate with disease severity. Using standard HD keywords and terms, we identified 749 published studies from 1993 to 2011 based on the availability of demographic, biochemical, and clinical measures. The average and variability of each measure was abstracted and stratified according to pre‐far, pre‐close, early, mild, moderate, and severe HD stages. A fixed‐effect meta‐analysis on selected variables was conducted at various disease stages. A total of 1,801 different clinical variables and treatment outcomes were identified. Unified Huntington Disease Rating Scale (UHDRS) Motor, UHDRS Independence, and Trail B showed a trend toward separation between HD stages. Other measures, such as UHDRS Apathy, Verbal Fluency, and Symbol Digit, could only distinguish between pre‐ and early stages of disease and later stages, whereas other measures showed little correlation with increasing HD stages. Using cross‐sectional data from published HD clinical trials, we have identified potential endpoints that could be used to track HD disease progression and treatment effect. Longitudinal studies, such as TRACK‐HD, are critical for assessing the value of potential markers of disease progression for use in future HD therapeutic trials. A list of variables, references used in this meta‐analysis, and database is available at http://www.cmmt.ubc.ca/research/investigators/leavitt/publications . © 2013 International Parkinson and Movement Disorder Society  相似文献   
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Thirty‐four patients have been studied from the time of initiation of pharmacological treatment in a long‐term prospective study of levodopa effects and disease progression in Parkinson's disease. Objective motor scoring of the response to levodopa in defined off states was performed every 3 years. The mean time from the initiation of levodopa treatment to the most recent measurements was 18.2 years. Of 8 patients who are still alive, only 3 had none of the features of the advanced disease phase (dementia, hallucinations, frequent falling). Off‐phase motor function worsened at a yearly rate of 1.9% of the maximum disability score, although the plots of the serial scores showed that the magnitude of the levodopa response is well preserved. There was little difference in the rate of progression between patients with tremor‐dominant and non‐tremor‐dominant motor subtypes. Those who developed dementia had more rapid deterioration of motor scores, with significantly worse off‐phase (P = .008) and on‐phase (P = .03) motor function. A graph of serial scores of patients who have died, aligned for time of death, showed an upward curving trend of motor disability in the last 5 years of the disease course. Its advanced phase may reveal that Parkinson's disease has an exponential pattern of progression. © 2013 Movement Disorder Society  相似文献   
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