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ABSTRACT: BACKGROUND AND PURPOSE:Patients with cervical spine syndrome often experience pain during the MR examination. Our aim was to compare the quality of cervical spine MR images obtained by parallel imaging with those of nonaccelerated images, with the goal of shortening the examination time while preserving adequate image quality.MATERIALS AND METHODS:A phantom study and examinations of 10 volunteers and 26 patients were conducted on a clinical 3T scanner. Acquisitions included axial T2WI, sagittal T2WI, T1WI, and T2TIRM sequences. Nonaccelerated sequences and accelerated sequences with different numbers of averages and different accelerations, with a scanning time reduction of 67%, were performed. For quantitative analysis, the SNR was obtained from the phantom measurements, and the NU was calculated from the volunteer measurements. For qualitative analysis, 3 independent readers assessed the delineation of anatomic structures in volunteers and the visibility of degenerative disease in patients.RESULTS:In the phantom study, as expected, the SNR of the nonaccelerated images was higher than the SNR of the same sequence with parallel imaging. In vivo, the NU was higher when applying fewer averages or parallel imaging, compared with the nonaccelerated images. The analysis of the subjective parameters in the volunteers and patients showed that a scanning time of 48% of the original protocol could be obtained by combining the following sequences: sagittal T1WI with 1 average; sagittal T2WI with acceleration factor 3; sagittal T2TIRM with acceleration factor 2; and axial T2* GRE with acceleration factor 2.CONCLUSIONS:Parallel imaging of the cervical spine at 3T allows shortening of the examination time by 52%, preserving adequate image quality.
American Journal of Neuroradiology 05/2012; · 2.93 Impact Factor
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ABSTRACT: Das Spektrum pathologischer Veränderungen in den anatomischen Sektionen des Hypopharynx erstreckt sich von benignen Pathologien
bis zum Hypopharynxkarzinom (CA). Neben dem klinischen Befund und einer endoskopischen Abklärung durch den Hals-Nasen-Ohren-Arzt
kommt den bildgebenden Verfahren im Rahmen der prä- und posttherapeutischen Diagnostik sowie im Follow-up hypopharyngealer
Krankheitsbilder, insbesondere bei bösartigen Veränderungen, eine entscheidende Rolle zu. Die konventionelle Röntgenschluckuntersuchung
sowie die kontrastmittelverstärkte Multidetektorcomputertomographie (MDCT) und Magnetresonanztomographie (MRT) und auch die
Positronenemissionstomographie (PET) und Positronenemissionstomographie-Computertomographie (PET-CT) kommen hier je nach Fragestellung
bzw. Krankheitsbild zum Einsatz. Insbesondere in der radiologischen Onkologie ist es wichtig, in klinisch schwierig beurteilbaren
Regionen die exakte Lokalisation und Ausdehnung hypopharyngealer Pathologien zu erfassen, um für den Patienten die optimale
Therapie zu planen.
Der folgende Artikel demonstriert das radiologische Erscheinungsbild pathologischer Veränderungen des Hypopharynx und diskutiert
insbesondere das Hypopharynx-CA im Brennpunkt der prä- und posttherapeutischen Bildgebung.
The spectrum of pathological changes in anatomical sections of the hypopharynx ranges from benign pathologies to hypopharyngeal
carcinoma. Beside the clinical status and the endoscopic evaluation performed by ear, nose and throat specialists, imaging
techniques play an important role in pre-therapeutic and post-therapeutic diagnostics and in the follow-up of pharyngeal disease
patterns, especially for malignant lesions. A conventional x-ray swallow examination, contrast-enhanced multidetector computed
tomography (MDCT) and magnetic resonance imaging (MRI), as well as positron emission tomography (PET) and positron emission
tomography computed tomography (PET-CT) are applied depending on the medical question and disease. Especially in radiological
oncology, it is extremely important in regions which are clinically difficult to assess to determine the exact localization
and extent of hypopharyngeal pathologies to plan the optimal therapy for the patient.
This article demonstrates the radiological appearance of pathological changes of the hypopharynx and discusses in particular
the hypopharynx carcinoma in the focus of pre-therapeutic and post-therapeutic imaging.
Der Radiologe 12/2008; 49(1):36-42. · 0.61 Impact Factor
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ABSTRACT: Larynx und Pharynx repräsentieren sowohl anatomisch als auch funktionell ein sehr komplexes Organsystem, das als Luft- und
Speiseweg dient. Die Kenntnis der Anatomie und anatomischen Topographie ist daher die elementare Grundlage für die Beurteilung
jeglicher pathologischer Prozesse.
Neben der klinischen Untersuchung und der Endoskopie durch den Hals-Nasen-Ohren-Arzt kommt den bildgebenden Verfahren in der
prä- und posttherapeutischen Diagnostik eine entscheidende Rolle zu. Der Radiologe bedient sich hierbei – in Abhängigkeit
von der Fragestellung – der konventionellen Röntgenschluckuntersuchung, der kontrastmittelverstärkten Multidetektorcomputertomographie
(MDCT), der Magnetresonanztomographie (MRT), der Positronenemissionstomographie (PET) und der Positronenemissionstomographie-Computertomographie
(PET-CT).
Der folgende Artikel demonstriert die funktionelle und insbesondere die strukturelle Anatomie des Larynx und Pharynx. Darüber
hinaus wird das breite Spektrum der bildgebenden Verfahren im klinischen Einsatz diskutiert.
The larynx and the pharynx represent anatomically as well as functionally a very complex organ which serves as an airway and
a nutrition channel. Knowledge of anatomy and anatomical topography is therefore a fundamental basis for the evaluation of
any pathological process.
Beside the clinical examination and endoscopy performed by ear, nose and throat specialists, imaging techniques play a crucial
role in pre-therapeutic and post-therapeutic diagnostics. The radiologist employs a conventional x-ray swallow examination,
as well as contrast-enhanced multidetector computed tomography (MDCT), magnetic resonance imaging (MRI), positron emission
tomography (PET) and positron emission tomography-computed tomography (PET-CT), depending on the medical problem in question.
The following article demonstrates the functional and especially the structural anatomy of the larynx and the pharynx. Furthermore,
the broad range of imaging techniques in clinical use is discussed.
Der Radiologe 12/2008; 49(1):8-16. · 0.61 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The spectrum of pathological changes in anatomical sections of the hypopharynx ranges from benign pathologies to hypopharyngeal carcinoma. Beside the clinical status and the endoscopic evaluation performed by ear, nose and throat specialists, imaging techniques play an important role in pre-therapeutic and post-therapeutic diagnostics and in the follow-up of pharyngeal disease patterns, especially for malignant lesions. A conventional x-ray swallow examination, contrast-enhanced multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI), as well as positron emission tomography (PET) and positron emission tomography computed tomography (PET-CT) are applied depending on the medical question and disease. Especially in radiological oncology, it is extremely important in regions which are clinically difficult to assess to determine the exact localization and extent of hypopharyngeal pathologies to plan the optimal therapy for the patient. This article demonstrates the radiological appearance of pathological changes of the hypopharynx and discusses in particular the hypopharynx carcinoma in the focus of pre-therapeutic and post-therapeutic imaging.
Der Radiologe 12/2008; 49(1):36-42. · 0.61 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The larynx and the pharynx represent anatomically as well as functionally a very complex organ which serves as an airway and a nutrition channel. Knowledge of anatomy and anatomical topography is therefore a fundamental basis for the evaluation of any pathological process. Beside the clinical examination and endoscopy performed by ear, nose and throat specialists, imaging techniques play a crucial role in pre-therapeutic and post-therapeutic diagnostics. The radiologist employs a conventional x-ray swallow examination, as well as contrast-enhanced multidetector computed tomography (MDCT), magnetic resonance imaging (MRI), positron emission tomography (PET) and positron emission tomography-computed tomography (PET-CT), depending on the medical problem in question. The following article demonstrates the functional and especially the structural anatomy of the larynx and the pharynx. Furthermore, the broad range of imaging techniques in clinical use is discussed.
Der Radiologe 12/2008; 49(1):8-16. · 0.61 Impact Factor
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[hide abstract]
ABSTRACT: To demonstrate intratumoral susceptibility effects in malignant brain tumors and to assess visualization of susceptibility effects before and after administration of the paramagnetic contrast agent MultiHance (gadobenate dimeglumine; Bracco Imaging), an agent known to have high relaxivity, with respect to susceptibility effects, image quality, and reduction of scan time.
Included in the study were 19 patients with malignant brain tumors who underwent high-resolution, susceptibility-weighted (SW) MR imaging at 3 T before and after administration of contrast agent. In all patients, Multihance was administered intravenously as a bolus (0.1 mmol/kg body weight). MR images were individually evaluated by two radiologists with previous experience in the evaluation of pre- and postcontrast 3-T SW MR images with respect to susceptibility effects, image quality, and reduction of scan time.
In the 19 patients 21 tumors were diagnosed, of which 18 demonstrated intralesional susceptibility effects both in pre- and postcontrast SW images, and 19 demonstrated contrast enhancement in both SW images and T1-weighted spin-echo MR images. Conspicuity of susceptibility effects and image quality were improved in postcontrast images compared with precontrast images and the scan time was also reduced due to decreased TE values from 9 min (precontrast) to 7 min (postcontrast).
The intravenous administration of MultiHance, an agent with high relaxivity, allowed a reduction of scan time from 9 min to 7 min while preserving excellent susceptibility effects and image quality in SW images obtained at 3 T. Contrast enhancement and intralesional susceptibility effects can be assessed in one sequence.
Neuroradiology 02/2008; 50(1):9-16. · 2.82 Impact Factor
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K Pinker, I M Noebauer-Huhmann,
I Stavrou,
R Hoeftberger,
P Szomolanyi,
G Karanikas,
M Weber,
A Stadlbauer,
E Knosp,
K Friedrich,
S Trattnig
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ABSTRACT: The purpose of this work was to demonstrate susceptibility effects (SusE) in various types of brain tumors with 3T high-resolution (HR)-contrast-enhanced (CE)-susceptibility-weighted (SW)-MR imaging and to correlate SusE with positron-emission tomography (PET) and histopathology.
Eighteen patients with brain tumors, scheduled for biopsy or tumor extirpation, underwent high-field (3T) MR imaging. In all of the patients, an axial T1-spin-echo (SE) sequence and an HR-SW imaging sequence before and after IV application of a standard dose of contrast agent (MultiHance) was obtained. Seven patients preoperatively underwent PET. The frequency and formation of intralesional SusE in all of the images were evaluated and correlated with tumor grade as determined by PET and histopathology. Direct correlation of SusE and histopathologic specimens was performed in 6 patients. Contrast enhancement of the lesions was assessed in both sequences.
High-grade lesions demonstrated either high or medium frequency of SusE in 90% of the patients. Low-grade lesions demonstrated low frequency of SusE or no SusE. Correlation between intralesional frequency of SusE and histopathologic, as well as PET, tumor grading was statistically significant. Contrast enhancement was equally visible in both SW and SE sequences. Side-to-side comparison of tumor areas with high frequency of SusE and histopathology revealed that intralesional SusE reflected conglomerates of increased tumor microvascularity.
3T HR-CE-SW-MR imaging shows both intratumoral SusE not visible with standard MR imaging and contrast enhancement visible with standard MR imaging. Because frequency of intratumoral SusE correlates with tumor grade as determined by PET and histopathology, this novel technique is a promising tool for noninvasive differentiation of low-grade from high-grade brain tumors and for determination of an optimal area of biopsy for accurate tumor grading.
American Journal of Neuroradiology 09/2007; 28(7):1280-6. · 2.93 Impact Factor
