Search results for "imagin."
showing 10 items of 7170 documents
Quantitative myocardial perfusion imaging using different autocalibrated parallel acquisition techniques
2008
Purpose To compare three different autocalibrated parallel acquisition techniques (PAT) for quantitative and semiquantitative myocardial perfusion imaging. Materials and Methods Seven healthy volunteers underwent myocardial first-pass perfusion imaging at rest using an SR-TrueFISP pulse sequence without PAT and while using GRAPPA, mSENSE, and TSENSE. signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), normalized upslopes (NUS), and myocardial blood flow (MBF) were calculated. Artifacts, image noise, and overall image quality were qualitatively assessed. Furthermore, the relation between signal intensity (SI) and contrast medium (CM) concentration was determined in phantoms. Results …
The Functional Role of Large-scale Brain Network Coordination in Placebo-induced Anxiolysis
2018
Abstract Anxiety reduction through mere expectation of anxiolytic treatment effects (placebo anxiolysis) has enormous clinical importance. Recent behavioral and electrophysiological data suggest that placebo anxiolysis involves reduced vigilance and enhanced internalization of attention; however, the underlying neurobiological mechanisms are not yet clear. Given the fundamental function of intrinsic connectivity networks (ICNs) in basic cognitive processes, we investigated ICN activity patterns associated with externally and internally directed mental states under the influence of an anxiolytic placebo medication. Based on recent findings, we specifically analyzed the functional role of the…
Evidence for modulation of opioidergic activity in central vestibular processing: A [(18)F] diprenorphine PET study.
2009
Animal and functional imaging studies had identified cortical structures such as the parieto‐insular vestibular cortex, the retro‐insular cortex, or the anterior cingulate cortex belonging to a vestibular cortical network. Basic animal studies revealed that endorphins might be important transmitters involved in cerebral vestibular processing. The aim of the present study was therefore to analyse whether the opioid system is involved in vestibular neurotransmission of humans or not. Changes in opioid receptor availability during caloric air stimulation of the right ear were studied with [(18)F] Fluoroethyl‐diprenorphine ([(18)F]FEDPN) PET scans in 10 right‐handed healthy volunteers and compa…
Prevalence and clinical significance of incidental findings on multiparametric prostate MRI.
2019
Purpose: To assess the prevalence and clinical significance of incidental findings (IFs) detected at multiparametric prostate MRI examination. Materials and methods: Multiparametric prostate MRIs of 647 consecutive patients (mean age 67.1 ± 8.0 years) were retrospectively evaluated by two radiologists recording the presence of all extra-prostatic IFs. Findings were classified as related to or not related to genitourinary system and divided into three classes, according to their clinical significance, as follows: group 1, not significant or scarcely significant; group 2, moderately or potentially significant; and group 3, significant. Differences in distribution of IFs between patients ≤ 65 …
Subcutaneous interferon β-1a may protect against cognitive impairment in patients with relapsing-remitting multiple sclerosis: 5-year follow-up of th…
2013
ObjectiveTo assess the effects of subcutaneous (sc) interferon (IFN) -1a on cognition over 5 years in mildly disabled patients with relapsing-remitting multiple sclerosis (RRMS).MethodsPatients aged 18-50 years with RRMS (Expanded Disability Status Scale score ≤4.0) who had completed the 3-year COGIMUS study underwent standardized magnetic resonance imaging, neurological examination, and neuropsychological testing at years 4 and 5. Predictors of cognitive impairment at year 5 were identified using multivariate analysis.ResultsOf 331 patients who completed the 3-year COGIMUS study, 265 participated in the 2-year extension study, 201 of whom (75.8%; sc IFN β-1a three times weekly: 44 µg, n = …
Focal nodular hyperplasia-like lesions in patients with cavernous transformation of the portal vein: prevalence, MR findings and natural history.
2011
PURPOSE: To retrospectively investigate the prevalence, MR findings, natural history, and association with other hepatic lesions of focal nodular hyperplasia (FNH)-like lesions in a cohort of consecutive patients with cavernous transformation of the portal vein (CTPV). MATERIALS AND METHODS: This retrospective IRB-approved study comprised 58 patients (32 men, 26 women; average age, 50 years) with CTPV who underwent liver MR imaging between 2000 and 2008. MR images were assessed by two radiologists in consensus for the presence of (a) FNH-like lesions and other liver lesions, and (b) other imaging findings. Patients were assigned to a stable or progressive clinical course based on lesion cha…
Academia in cardiovascular radiology: are we doing enough for the future of the subspecialty?
2021
Aim To explore barriers to academic activities that cardiovascular radiology-oriented radiology trainees face worldwide. Materials and methods An international call for participation in an online survey was distributed via social media and radiological societies to radiology trainees. Questions covered barriers and involvement in academic activities during radiology training. Participants interested in cardiovascular radiology were selected for analysis with appropriate statistical methods. Results Of the 892 respondents, 120 (13.5%) reported an interest in cardiovascular imaging. The majority (63.3%, 76/120) were from Europe and 57.5% (69/120) were men. There were gender discrepancies in a…
Management of intralabyrinthine schwannomas
2006
Abstract Objectives Our protocol to manage the intralabyrinthine schwannoma (ILS). Methods Retrospective chart review of 7 consecutive patients managed for ILS. Results Five patients underwent surgical removal of the lesions and none experienced significant complications or recurrent disease. One patient refused surgical treatment and was closely followed by serial MRI scans with no signs of tumor growth. One patient is presently managed conservatively due to a good hearing. Conclusions Diagnosis of ILS is based on high resolution MRI scans and should be included in the differential diagnosis of patients investigated for cochleovestibular symptoms. Treatment modality of ILS is controversial…
Perihepatic lymph nodes and antiviral response in chronic HCV-associated hepatitis.
2003
To identify predictive factors of response to interferon alpha (IFN-alpha) plus ribavirin therapy in patients with chronic hepatitis C (CHC), the presence of lymphadenopathy (LyA) of the hepatoduodenal ligament and other variables were investigated. A total of 110 patients with histologically proven CHC were enrolled in this study. Ultrasound (US) was performed at the start and end of therapy and 6 months after stopping therapy. At baseline, LyA was present in 35 (43.7%) of 80 patients with alanine aminotransferase (ALT) values and grading was significantly higher than in the LyA-negative group. LyA was more frequent in nonresponders (nonR) than in relapsers (relR) or sustained responders (…
Analysis of Internal Jugular Vein Insufficiency—A Comparison of Two Ultrasound Methods
2006
Abstract Jugular venous valve insufficiency is a contributing factor to different pathologic conditions. For assessment of insufficiency, two ultrasound techniques have been developed, that are based on very different methodology (direct Doppler assessment versus air contrast ultrasound venography [ACUV]). This study was conducted to compare these two methods to improve comparability of existing studies and diagnostic accuracy in future studies. The function of 40 valves was determined in 20 individuals during a Valsalva maneuver. For direct Doppler assessment, valvular competence was assessed on basis of Doppler recordings, following recently established criteria. Valvular insufficiency in…