Search results for "030218 nuclear medicine & medical imaging"
showing 10 items of 1054 documents
Focal or whole-gland salvage prostate brachytherapy with iodine seeds with or without a rectal spacer for postradiotherapy local failure: How best to…
2016
International audience; PURPOSE: Salvage prostate permanent implant (sPPI) for postradiation local failure provides high rates of biochemical control. The cumulative dose delivered to the prostate and the rectum is still unknown. METHODS AND MATERIALS: We reviewed the postimplant CT-based dosimetry of 18 selected patients who underwent sPPI with I-125 seeds for isolated biopsy-proven local failure several years after external beam radiation therapy. Ten patients had whole-prostate sPPI, and 8 patients had multiparametric MRI-based focal sPPI. In 8 patients, hyaluronic acid (HA) gel was injected into the prostate rectum space. RESULTS: The median cumulative biological effective dose after EB…
Interobserver variability in rectum contouring in high-dose-rate brachytherapy for prostate cancer: A multi-institutional prospective analysis
2017
PURPOSE: The aim of this study was to evaluate the interobserver variability (KW) of rectum contouring, and its dosimetric consequences, for high-dose-rate brachytherapy in patients with prostate cancer across multiple institutions. METHODS AND MATERIALS: Five radiation oncologists contoured rectums in 10 patients on transperineal ultrasound image sets after establishing a delineation consensus. The D-0.1cc, D-1cc, and D-2cc rectum volume parameters were determined. The mean, standard deviation, and range of each dose-volume histogram parameter were evaluated for each patient. The JOY was determined using the coefficient of variation, and the dosimetric impacts on the total dose were analyz…
Acute and late toxicity and preliminary outcomes report of moderately hypofractionated helical tomotherapy for localized prostate cancer: a mono-inst…
2019
Aims: To assess toxicity and clinical outcomes of moderately hypofractionated helical tomotherapy (HT) for the curative treatment of localized prostate cancer (PC). Methods: From December 2012 to May 2018, 170 patients were treated with definitive intent for PC. Thirty-four percent were low risk, 30% intermediate risk (IR) and 36% high risk (HR). All patients received 70 Gy in 28 fractions to the prostate; 61.6 Gy were delivered to the seminal vesicles for IR; pelvic lymph nodes irradiation for a total dose of 50.4 Gy was added in the HR subgroup. Toxicity was assessed using CTCAE V4.0, and biochemical failure was defined following Phoenix criteria. Time-to-event data were analyzed using th…
Preliminary experience with a transcranial magnetic resonance-guided focused ultrasound surgery system integrated with a 1.5-T MRI unit in a series o…
2018
OBJECTIVETranscranial magnetic resonance–guided focused ultrasound surgery (tcMRgFUS) is one of the emerging noninvasive technologies for the treatment of neurological disorders such as essential tremor (ET), idiopathic asymmetrical tremor-dominant Parkinson’s disease (PD), and neuropathic pain. In this clinical series the authors present the preliminary results achieved with the world’s first tcMRgFUS system integrated with a 1.5-T MRI unit.METHODSThe authors describe the results of tcMRgFUS in a sample of patients with ET and with PD who underwent the procedure during the period from January 2015 to September 2017. A monolateral ventralis intermedius nucleus (VIM) thalamic ablation was pe…
Effects of manganese injected into rat nostrils: implications for in vivo functional study of olfaction using MEMRI.
2011
WOS: 000298212500007; International audience; Manganese-enhanced magnetic resonance imaging (MEMRI) is a powerful tool for visualizing neuronal pathways and mapping brain activity modulation. A potential drawback of MEMRI lies in the toxic effects of manganese (Mn), which also depend on its administration route. The aim of this study was to analyze the effects of Mn doses injected into the nostrils of rats on both olfactory perception and MRI contrast enhancement. For this purpose, doses in the range 0-8 μmol MnCl(2) were tested. Behavioral items were quantified with and without odor stimulation during the first 2 h following Mn injection. The MRI study was performed after 16 h of intermitt…
Imaging of Orthotopic Glioblastoma Xenografts in Mice Using a Clinical CT Scanner: Comparison with Micro-CT and Histology
2016
Purpose There is an increasing need for small animal in vivo imaging in murine orthotopic glioma models. Because dedicated small animal scanners are not available ubiquitously, the applicability of a clinical CT scanner for visualization and measurement of intracerebrally growing glioma xenografts in living mice was validated. Materials and Methods 2.5x106 U87MG cells were orthotopically implanted in NOD/SCID/ᵞc-/- mice (n = 9). Mice underwent contrast-enhanced (300 μl Iomeprol i.v.) imaging using a micro-CT (80 kV, 75 μAs, 360° rotation, 1,000 projections, scan time 33 s, resolution 40 x 40 x 53 μm) and a clinical CT scanner (4-row multislice detector; 120 kV, 150 mAs, slice thickness 0.5 …
Higher vascularity at infiltrated peripheral edema differentiates proneural glioblastoma subtype
2020
[EN] Background and purpose Genetic classifications are crucial for understanding the heterogeneity of glioblastoma. Recently, perfusion MRI techniques have demonstrated associations molecular alterations. In this work, we investigated whether perfusion markers within infiltrated peripheral edema were associated with proneural, mesenchymal, classical and neural subtypes. Materials and methods ONCOhabitats open web services were used to obtain the cerebral blood volume at the infiltrated peripheral edema for MRI studies of 50 glioblastoma patients from The Cancer Imaging Archive: TCGA-GBM. ANOVA and Kruskal-Wallis tests were carried out in order to assess the association between vascular fea…
Hemorragic presentation of Listeria Monocytogenes rhombencephalic abscess.
2020
Listeria monocytogenes (LM) bacterium is a cause of central nervous system (CNS) infection and the most common cause of rhombencephalitis in immunocompetent elderly. A prompt identification of this condition should be always desirable, since its clinical manifestations are often unspecific with prodromal symptoms leading to high rates of morbidity and mortality if underestimated. CNS listeriosis magnetic resonance imaging (MRI) findings are generally not specific. However, in the appropriate clinical setting, focal brainstem hyperintensity on T2-weighted pulse sequences associated with ring-enhancement pattern after i.v. contrast media injection should be suspicious of LM abscess. The diagn…
Tolerance-Inducing Dose of 3-Nitropropionic Acid Modulates bcl-2 and bax Balance in the Rat Brain: A Potential Mechanism of Chemical Preconditioning
2000
Many studies have reported ischemia protection using various preconditioning techniques, including single dose 3-nitropropionic acid (3-NPA), a mitochondrial toxin. However, the cellular signal transduction cascades resulting in ischemic tolerance and the mechanisms involved in neuronal survival in the tolerant state still remain unclear. The current study investigated the mRNA and protein expression of the antiapoptotic bcl-2 and the proapoptotic bax, two antagonistic members of the bcl-2 gene family, in response to a single dose of 3-NPA, to global cerebral ischemia–reperfusion, and to the combination of both 3-NPA-pretreatment and subsequent global cerebral ischemia–reperfusion. Brain h…
Changes of sonographic, magnetic resonance tomographic, electromyographic, and histopathologic findings within a 2-month period of examinations after…
1998
This study compares sonographical, histopathological, magnetic resonance imaging (MRI), and electromyographical (EMG) findings following acute muscle denervation. We performed an experimental denervation of the supraspinatus and infraspinatus muscles on 35 New Zealand white rabbits by segment resection of the suprascapular nerve. The sonographical appearance of the supraspinatus muscle was followed and documented at short time intervals within a 2-month follow-up period. The sonographical, histopathological, and MRI changes due to denervation suggest a regular pattern. Apart from the reduction of the muscle diameter, there were considerable sonographical signs of denervation with an increas…