Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 3 de 3
Filter
Add more filters










Database
Language
Publication year range
1.
Insights Imaging ; 8(3): 301-310, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28439719

ABSTRACT

OBJECTIVES: To determine the advantages of radiological imaging of a collection of full-term teratological fetuses in order to increase their scientific and educational value. BACKGROUND : Anatomical museums around the world exhibit full-term teratological fetuses. Unfortunately, these museums are regularly considered as "morbid cabinets". Detailed dysmorphological information concerning the exhibited specimens is often lacking. Moreover, fetuses with severe and complex congenital anomalies are frequently diagnosed incompletely, incorrectly or not at all. METHODS: In order to verify diagnoses and to enrich their educational and scientific value, we imaged 41 out of the 72 teratological specimens present in the collection of our Anatomy and Pathology Museum in Nijmegen (The Netherlands) by means of magnetic resonance imaging (MRI) and computed tomography (CT). Additionally, contemporary dysmorphological insights and 3D models are implemented in the teratology education of medical students and residents. CONCLUSIONS: Full-term teratological fetuses have become increasingly rare and deserve a prominent place in every anatomical museum; they are suitable for contemporary teratological research and education. Modern radiological techniques markedly enhance their scientific and didactic value. TEACHING POINTS: • To explore the scientific and educational potential of institutionalised teratological collections • To understand the additional value of radiological imaging in diagnosing teratological specimens • To learn about the specific settings of MRI parameters when scanning fixed specimens • To recognise specific internal dysmorphology in several congenital anomalies.

2.
NMR Biomed ; 28(3): 306-16, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25581510

ABSTRACT

The purpose of this work was to harmonize data acquisition and post-processing of single voxel proton MRS ((1) H-MRS) at 7 T, and to determine metabolite concentrations and the accuracy and reproducibility of metabolite levels in the adult human brain. This study was performed in compliance with local institutional human ethics committees. The same seven subjects were each examined twice using four different 7 T MR systems from two different vendors using an identical semi-localization by adiabatic selective refocusing spectroscopy sequence. Neurochemical profiles were obtained from the posterior cingulate cortex (gray matter, GM) and the corona radiata (white matter, WM). Spectra were analyzed with LCModel, and sources of variation in concentrations ('subject', 'institute' and 'random') were identified with a variance component analysis. Concentrations of 10-11 metabolites, which were corrected for T1 , T2 , magnetization transfer effects and partial volume effects, were obtained with mean Cramér-Rao lower bounds below 20%. Data variances and mean concentrations in GM and WM were comparable for all institutions. The primary source of variance for glutamate, myo-inositol, scyllo-inositol, total creatine and total choline was between subjects. Variance sources for all other metabolites were associated with within-subject and system noise, except for total N-acetylaspartate, glutamine and glutathione, which were related to differences in signal-to-noise ratio and in shimming performance between vendors. After multi-center harmonization of acquisition and post-processing protocols, metabolite concentrations and the sizes and sources of their variations were established for neurochemical profiles in the healthy brain at 7 T, which can be used as guidance in future studies quantifying metabolite and neurotransmitter concentrations with (1) H-MRS at ultra-high magnetic field.


Subject(s)
Brain/metabolism , Metabolome , Adult , Female , Humans , Magnetic Resonance Spectroscopy , Male , Models, Theoretical , Reproducibility of Results , Signal-To-Noise Ratio
3.
Cancer Imaging ; 11: 259-65, 2012 Jan 12.
Article in English | MEDLINE | ID: mdl-22245974

ABSTRACT

OBJECTIVE: To assess the early vascular effects of sunitinib in patients with renal cell carcinoma (RCC) with diffusion-weighted magnetic resonance imaging (DWI), dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and T2* perfusion MRI. PATIENTS AND METHODS: In 10 patients with abdominal RCC lesions, DWI, DCE-MRI and T2* perfusion MRI measurements at 3 Tesla were performed at baseline, 3 and 10 days after start of sunitinib. VEGF-A plasma levels were measured on days 0, 3 and 10. RESULTS: DWI showed a significant increase in the apparent diffusion coefficient (×10(-6) s/mm(2)) from baseline (mean 1158, range 814-2003) to day 3 (mean 1306, range 1008-2097, P = 0.015) followed by a decrease to baseline levels at day 10 (mean 1132, range 719-2005, P = 0.001). No significant changes were found in mean DCE-MRI parameters. T2* perfusion MRI showed a significant decrease in relative tumor blood volume (rBV) and relative tumor blood flow (rBF) at day 3 (rBV P = 0.037, rBF P = 0.018) and day 10 (rBV P = 0.006, rBF P = 0.009). VEGF-A plasma levels significantly increased after 10 days, but did not correlate with MRI parameters. CONCLUSIONS: Sunitinib induces antiangiogenic effects as measured by DWI and T2*-perfusion MRI, 3 and 10 days after the start of the initial treatment. DCE-MRI did not show significant changes. In the near future, early functional MRI-based evaluation can play an important role in tailoring treatment to the individual patient with RCC. Further investigation is warranted.


Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Renal Cell/blood supply , Carcinoma, Renal Cell/drug therapy , Indoles/therapeutic use , Kidney Neoplasms/blood supply , Kidney Neoplasms/drug therapy , Magnetic Resonance Imaging/methods , Pyrroles/therapeutic use , Aged , Carcinoma, Renal Cell/diagnosis , Female , Humans , Kidney Neoplasms/diagnosis , Male , Middle Aged , Pilot Projects , Sunitinib , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL
...