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51.
David C. Johnson Steven S. Raman Sohrab A. Mirak Lorna Kwan Amirhossein M. Bajgiran William Hsu Cleo K. Maehara Preeti Ahuja Izak Faiena Aydin Pooli Amirali Salmasi Anthony Sisk Ely R. Felker David S.K. Lu Robert E. Reiter 《European urology》2019,75(5):712-720
Background
Multiparametric magnetic resonance imaging (mpMRI) undoubtedly affects the diagnosis and treatment of localized prostate cancer (CaP). However, clinicians need a better understanding of its accuracy and limitations in detecting individual CaP foci to optimize management.Objective
To determine the per-lesion detection rate for CaP foci by mpMRI and identify predictors of tumor detection.Design, setting, and participants
We carried out a retrospective analysis of a prospectively managed database correlating lesion-specific results from mpMRI co-registered with whole-mount pathology (WMP) prostatectomy specimens from June 2010 to February 2018. Participants include 588 consecutive patients with biopsy-proven CaP undergoing 3-T mpMRI before radical prostatectomy at a single tertiary institution.Outcome measurements and statistical analysis
We measured mpMRI sensitivity in detecting individual CaP and clinically significant (any Gleason score ≥7) CaP foci and predictors of tumor detection using multivariate analysis.Results and limitations
The final analysis included 1213 pathologically confirmed tumor foci in 588 patients with primarily intermediate- (75%) or high-risk (12%) CaP. mpMRI detected 45% of all lesions (95% confidence interval [CI] 42–47%), including 65% of clinically significant lesions (95% CI 61–69%) and nearly 80% of high-grade tumors. Some 74% and 31% of missed solitary and multifocal tumors, respectively, were clinically significant. The majority of missed lesions were small (61.1% ≤1 cm); 28.3% were between 1 and 2 cm, and 10.4% were >2 cm. mpMRI missed at least one clinically significant focus in 34% of patients overall, and in 45% of men with multifocal lesions. On multivariate analysis, smaller, low-grade, multifocal, nonindex tumors with lower prostate-specific antigen density were more likely to be missed. Limitations include selection bias in a prostatectomy cohort, lack of specificity data, an imperfect co-registration process, and uncertain clinical significance for undetected lesions.Conclusions
mpMRI detects less than half of all and less than two-thirds of clinically significant CaP foci. The moderate per-lesion sensitivity and significant proportion of men with undetected tumor foci demonstrate the current limitations of mpMRI.Patient summary
Magnetic resonance imaging of the prostate before surgical removal for prostate cancer finds less than half of all individual prostate cancer tumors. Large, solitary, aggressive tumors are more likely to be visualized on imaging. 相似文献52.
Angela M. Auriat Jennifer K. Ferris Sue Peters Joel Ramirez Sandra E. Black Claudia Jacova Lara A. Boyd 《Journal of stroke and cerebrovascular diseases》2019,28(2):381-388
Background and Aims
In addition to overt stroke lesions, co-occurring covert lesions, including white matter hyperintensities (WMH) and covert lacunar infarcts (CLI), contribute to poststroke outcome. The purpose of this study was to examine the relationship between covert lesions, and motor and cognitive outcomes in individuals with chronic stroke.Methods
Volumetric quantification of clinically overt strokes, covert lesions (periventricular and deep: pWMH, dWMH, pCLI, dCLI), ventricular and sulcal CSF (vCSF, sCSF), and normal appearing white (NAWM) and gray matter (NAGM) was performed using structural magnetic resonance imaging. We assessed motor impairment and function, and global cognition, memory, and other cognitive domains. When correlation analysis identified more than one MR parameter relating to stroke outcomes, we used regression modeling to identify which factor had the strongest impact.Results
Neuropsychological and brain imaging data were collected from 30 participants at least 6 months following a clinically diagnosed stroke. Memory performance related to vCSF (r = ?0.52, P = .004). The strongest predictor of nonmemory domains was pCLI (r2 = 0.28, P = .004). Motor impairment and function were most strongly predicted by the volume of stroke and NAWM (r2 = 0.36; P = .001), and dWMH (r2 = 0.39; P = .001) respectively.Conclusions
Covert lesion type and location have important consequences for post-stroke cognitive and motor outcome. Limiting the progression of covert lesions in aging populations may enhance the degree of recovery post-stroke. 相似文献53.
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55.
Soft tissue sarcomas (STS) are rare tumours presenting as soft tissue lumps. Ultrasound is often the primary modality for the initial assessment, with MRI the mainstay for lesion characterisation. PET/CT along with other emerging MRI sequences are used in certain situations as an adjunct and problem solving tool in STS staging and assessment of disease recurrence. Recent advances include the promise of whole body MRI, hybrid PET/MRI, diffusion weighted imaging, dynamic contrast enhanced MRI and advances in artificial intelligence. This article discusses current concepts in extremity STS imaging and highlights recent advances. 相似文献
56.
BackgroundSmoking is a poor prognostic factor for healing after rotator cuff repair and is associated with inferior results. We hypothesized that smokers would have higher recurrent tear rates and more postoperative myotendinous junction (MTJ) retraction in healed repairs than nonsmokers three months postoperatively.MethodsRotator cuff repairs (RCRs) were retrospectively reviewed over a 2-year period. Patients underwent magnetic resonance imaging (MRI) within 6 months prior to surgery and again at 3 months postoperatively. Seventy-nine patients were included and stratified by smokers versus nonsmokers. Baseline patient demographics, tear characteristics, and surgical factors were collected. Preoperative and postoperative MRIs were assessed to quantify the MTJ position and to establish the recurrent tear rate.ResultsFor the total cohort (nonsmokers, n = 56; smokers, n = 23), significant differences in age, race, and traumatic onset of injury existed between groups. There were no significant differences in recurrent tear between smokers (26%) and nonsmokers (27%), but nonsmokers were more satisfied. For patients with healed RCRs (nonsmokers, n = 41; smokers, n = 17), there were significant differences in race. On univariate analysis, nonsmokers had a significantly more lateral MTJ postoperatively (P = 0.05). On multivariable regression analysis, medialized postoperative MTJ position in healed cuffs was driven only by greater preoperative rotator cuff retraction preoperatively. There were no significant differences in MTJ position based on smoking status for patients with healed RCRs.ConclusionSmoking does not appear to be an independent risk factor for postoperative MTJ retraction in healed RCRs, also known as failure in continuity. Preoperative tear size and retraction play the biggest roles in predicting postoperative MTJ position, regardless of smoking status. There are no significant differences in patient-reported outcomes for patients with healed RCRs, but nonsmokers had more satisfaction following RCR in the total cohort.Level of EvidenceLevel III; Retrospective cohort study; Diagnostic study 相似文献
57.
《Brain stimulation》2021,14(5):1118-1125
BackgroundWhen repetitive transcranial magnetic stimulation (rTMS) is used to treat medication refractory depression, the treatment pulse intensity is individualized according to motor threshold (MT). This measure is often acquired only on the first day of treatment, as per the protocol currently approved by Food and Drug Administration.ObjectiveHere, we aimed to assess daily MT variability across an rTMS treatment course and simulate the effects of different schedules of MT assessment on treatment intensity.MethodsWe conducted a naturalistic retrospective study with 374 patients from a therapeutic rTMS program for depression that measures MT daily.ResultsFor each patient, in almost half the TMS sessions, MT varied on average more than 5% as compared to the baseline MT acquired in the first treatment day. Such variability was only minimally impacted by having different TMS technicians acquiring MT in different days. In a smaller cohort of healthy individuals, we confirmed that the motor hotspot localization method, a critical step for accurate MT assessment, was stable in different days, arguing that daily MT variability reflects physiological variability, rather than an artifact of measurement error. Finally, in simulations of the effect of one-time MT measurement, we found that half of sessions would have been 5% or more above or below target intensity, with almost 5% of sessions 25% above target intensity. The simulated effects of weekly MT measurements were significantly improved.ConclusionsIn conclusion, MT varies significantly across days, not fully dependent on methods of MT acquisition. This finding may have important implications for therapeutic rTMS practice regarding safety and suggests that regular MT assessments, daily or at least weekly, would ameliorate the effect. 相似文献
58.
《Clinical neurophysiology》2021,132(10):2639-2653
ObjectiveThis study brought together over 60 transcranial magnetic stimulation (TMS) researchers to create the largest known sample of individual participant single and paired-pulse TMS data to date, enabling a more comprehensive evaluation of factors driving response variability.MethodsAuthors of previously published studies were contacted and asked to share deidentified individual TMS data. Mixed-effects regression investigated a range of individual and study level variables for their contribution to variability in response to single and paired-pulse TMS data.Results687 healthy participant’s data were pooled across 35 studies. Target muscle, pulse waveform, neuronavigation use, and TMS machine significantly predicted an individual’s single-pulse TMS amplitude. Baseline motor evoked potential amplitude, motor cortex hemisphere, and motor threshold (MT) significantly predicted short-interval intracortical inhibition response. Baseline motor evoked potential amplitude, test stimulus intensity, interstimulus interval, and MT significantly predicted intracortical facilitation response. Age, hemisphere, and TMS machine significantly predicted MT.ConclusionsThis large-scale analysis has identified a number of factors influencing participants’ responses to single and paired-pulse TMS. We provide specific recommendations to minimise interindividual variability in single and paired-pulse TMS data.SignificanceThis study has used large-scale analyses to give clarity to factors driving variance in TMS data. We hope that this ongoing collaborative approach will increase standardisation of methods and thus the utility of single and paired-pulse TMS. 相似文献
59.
60.
《The Foot》2021
Few studies have reported about isolated contracture in the extensor hallucis longus (EHL) muscle, but none of the EHL muscle contracture after distal tibial physeal injury. Two such cases in 16- and 14-year-old boys who underwent surgeries for distal physeal injury of the tibia at a previous hospital are presented. Extension contracture of the hallux appeared 1–2 months post-surgery. Physical examinations revealed that the extension contracture of the first metatarsophalangeal joint was aggravated in plantar flexion of the ankle due to a tenodesis effect, and magnetic resonance imaging showed atrophy and signal changes in the anterior compartment muscles. This was diagnosed as EHL muscle contracture due to anterior compartment syndrome (ACS) after distal tibial physeal injury. The EHL tendon transfers were performed in both cases, with favorable short-term results. Therefore, the EHL tendon transfer might be preferable in case of the EHL muscle contracture due to partial ACS. 相似文献