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81.
Kevin Martell Hans Chung Gerard Morton Danny Vesprini Chia-Lin Tseng Ewa Szumacher Patrick Cheung Will Chu Stanley Liu Andrew Loblaw 《Canadian Urological Association journal》2022,16(8):E437
IntroductionWe aimed to determine the minimum cross-sectional ellipsoid area on magnetic resonance (MR) of intraprostatic nodules that best predicts for subsequent targeted biopsies revealing ≥ grade group (GG) 2 disease.MethodsForty-six patients previously diagnosed with GG 1 prostate adenocarcinoma who received cognitively fused, MR-guided, transperineal targeted biopsies in addition to six random biopsies were included in this analysis. A Youden cutpoint analysis was used to determine the ellipsoid area in the axial plane best predicting for ≥GG 2 disease within the targeted biopsy cores and logistic regression used to assess the result.ResultsMedian time from MR imaging to targeted biopsy was 2.4 (1.4–5.5) months. Forty of 46 (87%) patients had one nodule and 6/46 (13%) had two separate nodules on MR that received targeted biopsy. Of the 52 nodules, five (10%), 33 (63%), and 14 (27%) were Prostate Imaging-Reporting and Data System (PI-RADS) 3, 4, and 5, respectively. Thirteen (25%), six (12%), and 33 (64%) were in the anterior, medial, and posterior regions of the prostate, respectively. Median area was 0.72 (0.49–1.29) cm2 (average diameter 9.5 mm). Fifteen of 46 (33%) patients had ≥1 random biopsy and 20/52 (38%) nodules had ≥1 targeted biopsy revealing ≥GG 2 disease. The optimal area cutpoint was ≥0.7 cm2, with an area under the curve of 0.671 (0.510–0.832). On logistic regression, area ≥0.7 cm2 was solely predictive of targeted biopsy revealing ≥GG 2 disease (odds ratio 6.5, 1.3–32.4, p=0.022).ConclusionsNodule area ≥0.7 cm2 may predict for transperineal-based targeted biopsies being positive for ≥GG 2 disease when 1–2 cores are taken. 相似文献
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David J. Schenk Dave Hesk Rosemary Marques Roy Helmy Patty Cheung 《Journal of labelled compounds & radiopharmaceuticals》2012,55(12):447-449
The specific activities for a series of S‐35 tracers were found to vary from the decay‐corrected specific activity of the labeled reagent. If not known before the stock solution preparation and binding assay, this variation would have resulted in performing the assay at approximately two to three times over the targeted concentration, thereby leading to considerable error in the calculated binding and related conclusions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
84.
通过回顾香港地区肿瘤放射治疗设备、人员、技术等情况的进展,可为广大读者提供一个简单清晰的脉络,并帮助了解香港地区肿瘤放射治疗学创建与发展过程。此报告是对香港地区肿瘤放射治疗学发展的宣传与肯定,也更是为扩大放射肿瘤学科交流和发展提供契机。 相似文献
85.
Metastases of prostate carcinoma to the central nervous system are rare, while dural metastases are even rarer. Patients are often clinically asymptomatic or present with non-specific symptoms, rendering the condition unsuspected. The imaging findings could resemble benign conditions and be misdiagnosed as such when the diagnosis is not considered. We present an unusual case of dural metastasis from carcinoma of the prostate mimicking acute sub-dural hematoma as shown on non-contrast-enhanced CT. The radiological features are analyzed, and clues to differentiating the two conditions are discussed. 相似文献
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The authors present a method for obtaining magnetic resonance (MR) images of intra- and extracranial vessels from thin contiguous transaxial sections. A section-selective gradient refocusing pulse sequence with a short repetition time caused flow-related enhancement from spins that flowed perpendicular to the transaxial sections. The signal was further enhanced by means of flow compensation gradients to rephase any phase shifts resulting from moving spins in the presence of the imaging gradients. Coronal and sagittal sections, reformatted from multiple transaxial sections, are shown to have excellent vessel contrast without the use of contrast material. These images were obtained in 12 minutes of acquisition time from as many as 60 sections of 3-mm thickness. Such a technique shows significant promise for MR angiography. 相似文献
88.
We surveyed cognitively normal teens with and without chronic illness regarding the perceived physical and social impact of various chronic diseases including asthma.The overall physical impact of asthma was perceived equivalently to diabetes and arthritis, but less than epilepsy, Down's syndrome, leukemia, and human immunodeficiency virus infection. However, asthma was rated to more commonly cause physical disability (p < 0.001) and restrict activities (p < 0.0005). The social impact of asthma was perceived equivalently to diabetes, but more favorably than the other chronic diseases surveyed. Specifically, teens with asthma were perceived as having fewer behavior problems, being more honest, popular, and fun to be around, but less adept at sports. Only 6 of 149 (4%) teens surveyed expressed any degree of reluctance to befriend peers with asthma. 相似文献
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90.
Jen-Li Looi Lily Cheung Alex Pui-Wai Lee 《The international journal of cardiovascular imaging》2013,29(3):529-531
An 85-year-old man with history of hypertension presented with fever, cough and abdominal pain. Unfortunately fever and leukocytosis persisted despite treatment. Blood cultures obtained on admission grew Salmonella enteritidis. Subsequently he developed increasing back pain and transoesophageal echocardiography (TOE) was performed, demonstrating a complex ulcer at the aortic arch with multiple small mobile strandlike densities suggestive of vegetation. Contrast thoracic CT scan confirmed an ulcerated atherosclerotic plaque which progressively increasing in size over 3 months despite antibiotics. Therefore, a stent was deployed in view of high risk of perforation and he was placed on prolonged antibiotics. Post-stenting CT scan a few months later showed a patent stent with the aneurysm remained stable in size. Cardiovascular infections develop in approximately 25 % of patients with Salmonella bacteremia. Most patients with Salmonella aortitis have preexisting atherosclerosis at the site of the subsequently infected aneurysm. The diagnosis of S. aortitis can be challenging, because the clinical course may be indolent and the symptoms are nonspecific. A high index of suspicion is required to make the diagnosis of S. aortitis, especially in patients with Salmonella bacteraemia, fever, back pain and/or abdominal pain. This case highlights the usefulness of TOE in the evaluation of diseases involving the thoracic aorta, leading to a successful intervention. 相似文献