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Mathias Goyen

Publications and source records attributed to Mathias Goyen.

At least 37 records · Page 2Linked to original sources
PubMed2005

Elective full-body screening examinations: a plea for MRI.

The use of imaging is generally focussed on detecting and characterising suspected or known disease in symptomatic patients. Experience with preventative imaging, aiming at the detection of disease prior to its symptomatic manifestation, is limited. Screening involves the evaluation of asymptomatic individuals at risk for the presence of a particular disease. A screening test is designed to detect a targeted disease at a stage which still permits treatment to succeed in avoiding morbidity and/or mortality. Diseases worthy of screening should be associated with high morbidity and/or mortality if proper treatment is not applied sufficiently early. The screening test itself must not cause harm to the examined subjects. For the test to be cost-effective, the target disease should be highly prevalent in the screened population. Restricting screening to a population known to be at increased risk for the target disease enhances the test's effectiveness.

Colonic Diseases↗
PubMed2004

Contrast-enhanced MR Angiography of the renal arteries: blinded multicenter crossover comparison of gadobenate dimeglumine and gadopentetate dimeglumine.

PURPOSE: To prospectively and intraindividually compare 0.1 mmol/kg gadobenate dimeglumine with 0.2 mmol/kg gadopentetate dimeglumine for contrast material-enhanced magnetic resonance (MR) angiography of the renal arteries. MATERIALS AND METHODS: Institutional review board approval was granted by each of three participating centers. The study accorded with international standards for good clinical practice and Declaration of Helsinki and subsequent amendments. Patients gave written informed consent before enrollment. Patients (n = 34) underwent two MR angiographic examinations more than 48 hours but less than 12 days apart. Gadobenate dimeglumine followed by gadopentetate dimeglumine was administered in 18 patients; the order of administration was reversed in 16 patients. A 1.5-T MR imager was used with a phase-encoded three-dimensional spoiled breath-hold pulse sequence. Two blinded independent readers qualitatively assessed randomized subtracted maximum intensity projection images. A three-point scale for diagnostic quality (0, poor; 1a or 1p, moderate; and 2a or 2p, adequate [a and p refer, respectively, to absence and presence of vascular lesions]) was used to score each of nine segments of the abdominal aorta and both renal arteries (possible overall score, 18). Quantitative assessment (vessel signal-to-noise ratio [SNR], vessel-muscle contrast-to-noise ratio [CNR]) of source images was performed for regions of interest in supra-, juxta-, and infrarenal aorta segments and psoas muscle. Data were tested with analysis of variance for two-period crossover design. Interreader agreement was evaluated with Cohen kappa statistics. RESULTS: No difference in mean image quality between the two contrast agents was observed; scores for gadobenate dimeglumine and gadopentetate dimeglumine were 15.15 and 15.23 for reader 1 and 16.77 and 17.01 for reader 2. The order of contrast material administration likewise produced no quality differences: readers 1 and 2 reported scores of 14.4 +/- 4.2 (standard deviation) and 16.7 +/- 2.3, respectively, when gadobenate dimeglumine was given first, and 15.2 +/- 1.8 and 16.6 +/- 1.6, respectively, when gadopentetate dimeglumine was given first. Results of quantitative evaluation showed increasing SNR and CNR with gadobenate dimeglumine in segments at progressively lower levels of the aorta, but increases in SNR and CNR at the infrarenal aorta (48.3 vs 40.6 and 44.2 vs 36.4, respectively) were not significant (P = .05 for both). CONCLUSION: Gadobenate dimeglumine at a dose of 0.1 mmol/kg is comparable to gadopentetate dimeglumine at 0.2 mmol/kg for contrast-enhanced renal MR angiography.

Adult↗
PubMed2004

MR-based full-body preventative cardiovascular and tumor imaging: technique and preliminary experience.

Recent improvements in hardware and software, lack of side effects, as well as diagnostic accuracy make magnetic resonance imaging a natural candidate for preventative imaging. Thus, the purpose of the study was to evaluate the feasibility of a comprehensive 60-min MR-based screening examination in healthy volunteers and a limited number of patients with known target disease. In ten healthy volunteers (7 men, 3 women; mean age, 32.4 years) and five patients (4 men, 1 woman; mean age, 56.2 years) with proven target disease we evaluated the performance of a comprehensive MR screening strategy by combining well-established organ-based MR examination components encompassing the brain, the arterial system, the heart, the lungs, and the colon. All ten volunteers and five patients tolerated the comprehensive MR examination well. The mean in-room time was 63 min. In one volunteer, insufficient colonic cleansing on the part of the volunteer diminished the diagnostic reliability of MR colonography. All remaining components of the comprehensive MR examination were considered diagnostic in all volunteers and patients. In the five patients, the examination revealed the known pathologies [aneurysm of the anterior communicating artery ( n=1), renal artery stenosis ( n=1), myocardial infarct ( n=1), and colonic polyp ( n=2)]. The outlined MR screening strategy encompassing the brain, the arterial system, the heart, the lung, and the colon is feasible. Further studies have to show that MR-based screening programs are cost-effective in terms of the life-years saved.

Adult↗
PubMed2004

Gadopentetate dimeglumine-enhanced three-dimensional MR-angiography: dosing, safety, and efficacy.

Noninvasiveness, inherent three-dimensionality allowing reformations in any desired plane, and safe contrast agents, coupled with high diagnostic accuracy have driven the rise in popularity of contrast-enhanced MR angiography (CE-MRA) within the medical community. Reflecting its dominant market share as a paramagnetic contrast agent, gadopentetate dimeglumine (Gd-DTPA) has been used for the majority of clinically-performed MRA exams. Over the period January 1994 to February 2002, a total of 172 original studies describing the use of gadolinium-enhanced MRA in more than three human subjects were identified. Of these, 117 described the use of Gd-DTPA as the contrast agent for MRA. A total of 4046 subjects who received Gd-DTPA for MRA are described in these studies. Analysis of these data demonstrate Gd-DTPA to be a safe contrast agent for MRA when applied in a dose ranging from 0.1 to 0.3 mmol/kg of bodyweight. The documented clinical results show Gd-DTPA to be efficacious in the assessment of the arterial system. The effectiveness of Gd-DTPA-enhanced MRA extends beyond the detection, localization, and characterization of arterial disease, and encompasses choice and planning of appropriate therapy, as well as evaluation of therapeutic effectiveness.

Adult↗
PubMed2004

Whole body MR angiography screening.

Lack of side effects, diagnostic accuracy and recent improvements in technology qualify magnetic resonance imaging for preventive cardiovascular imaging. The purpose of this study was to assess the feasibility of a comprehensive contrast-enhanced three-dimensional whole-body MR (magnetic resonance) angiography examination technique using a rolling table platform system with a 1.5-T MR system. The examination yielded diagnostic image quality in 5312 out of 5400 (98.3%) evaluated vascular segments in 180 consecutive patients with peripheral vascular disease. Besides the proved peripheral vascular disease, additional relevant vascular disease was found in 65 vessel segments in 42 patients: carotid artery stenosis (n=21), subclavian artery stenosis (n=5), renal artery stenosis (n=27) abdominal aortic aneurysm (n=7), aortic dissection (n=5). In 20 patients additional imaging studies confirmed the results of whole-body MRA without false positive or false negative findings. The described whole-body MR angiography protocol appears well suited for comprehensive evaluation of the arterial system beyond the peripheral vasculature.

Adult↗
PubMed2004

Peripheral vasculature: whole-body MR angiography with midfemoral venous compression--initial experience.

Five volunteers and 10 patients suspected of having peripheral vascular disease underwent multistation contrast material-enhanced three-dimensional whole-body magnetic resonance (MR) angiography. The first examination, based on standard protocol, lasted 72 seconds, while the following two examinations, performed with a high-spatial-resolution T1-weighted gradient-recalled-echo sequence for the last two stations (lower extremities) lasted 170 seconds. In the second high-resolution examination, midfemoral venous compression was used. Intraindividual comparison showed the high-resolution protocol with venous compression resulted in the best qualitative and quantitative image quality through higher signal-to-noise and contrast-to-noise ratios in the calf arteries. Despite prolonged acquisition times, there was no venous contamination. The data suggest that midfemoral venous compression should be incorporated in multistation protocols of the lower extremities to improve depiction of calf arteries without disturbing venous overlap.

Adult↗
PubMed2004

Biomechanical incompatibility of popliteal stent placement.

Peripheral stents or endografts in specific arterial segments are exposed to extreme mechanical stress. Despite high rates of primary technical success, mechanical bending due to knee joint flexion can limit long-term patency of stents or endografts in the popliteal artery or the femoropopliteal segment. Every stent or endograft responds differently to bending during knee joint flexion, which can be revealed only by functional investigation. Mechanical bending has to be considered in future studies to assess the influence of differences in stent design, material, or postinterventional drug treatment on the long-term patency of endoprostheses in the femoropopliteal segment. To demonstrate the concept of biomechanical incompatibility, we present several illustrations of different stent designs placed in the popliteal artery.

Arterial Occlusive Diseases↗
PubMed2004

Whole-body 3D MR angiography of patients with peripheral arterial occlusive disease.

OBJECTIVE: We assessed the diagnostic performance of whole-body 3D contrast-enhanced MR angiography in comparison with digital subtraction angiography (DSA) of the lower extremities in patients with peripheral arterial occlusive disease. SUBJECTS AND METHODS. Fifty-one patients with clinically documented peripheral arterial occlusive disease referred for DSA of the lower extremity arterial system underwent whole-body MR angiography on a 1.5-T MR scanner. Paramagnetic gadobutrol was administered and five contiguous stations were acquired with 3D T1-weighted gradient-echo sequences in a total scanning time of 72 sec. DSA was available as a reference standard for the peripheral vasculature in all patients. Separate blinded data analyses were performed by two radiologists. Additional vascular disease detected by whole-body MR angiography was subsequently assessed on sonography, dedicated MR angiography, or both. RESULTS: All whole-body MR angiography examinations were feasible and well tolerated. AngioSURF-based whole-body MR angiography had overall sensitivities of 92.3% and 93.1% (both 95% confidence intervals [CIs], 78-100%) with specificities of 89.2% and 87.6% (both CIs, 84-98%) and excellent interobserver agreement (kappa = 0.82) for the detection of high-grade stenoses. Additional vascular disease was detected in 12 patients (23%). CONCLUSION: Whole-body MR angiography permits a rapid, noninvasive, and accurate evaluation of the lower peripheral arterial system in patients with peripheral arterial occlusive disease, and it may allow identification of additional relevant vascular disease that was previously undetected.

Adult↗
PubMed2004

The future of hospital-based radiological imaging.

Radiologic imaging has made dramatic progress over the last decades. The authors analyse all areas of current radiological imaging including conventional radiology, ultrasonography, computed tomography, magnetic resonance imaging, interventional radiology and nuclear medicine. Future opportunities and challenges regarding the subsequent development of imaging in general and radiology in particular are highlighted. Thus, the authors seek answers to questions such as: Will there be a need for radiologists? Will imaging become too costly? Possible remedies are suggested.

Diagnostic Imaging↗
PubMed2003

Detection of atherosclerosis: systemic imaging for systemic disease with whole-body three-dimensional MR angiography--initial experience.

In 100 consecutive patients with peripheral vascular disease whole-body three-dimensional magnetic resonance (MR) angiography was performed by using the rolling table platform system with a 1.5-T MR unit and five three-dimensional MR angiographic data sets during 72 seconds (0.2 mol per kilogram of body weight of gadobenate dimeglumine). Apart from the proved peripheral vascular disease, additional clinically relevant disease was found in 33 segments in 25 patients as follows: renal arterial narrowing (n = 15), carotid arterial stenosis (n = 12), subclavian arterial stenosis (n = 2), and abdominal aortic aneurysms (n = 4). Confirmatory studies performed in 11 patients in this study revealed no false-positive or false-negative findings at examination.

Adult↗
PubMed2003

MRI of the liver: can True FISP replace HASTE?

PURPOSE: To determine the diagnostic accuracy of two fast breath-hold magnetic resonance (MR) imaging sequences, half-Fourier acquired single turbo spin-echo (HASTE) and true fast imaging with steady state precession (TrueFISP), for the detection and characterization of focal liver lesions MATERIALS AND METHODS: A total of 186 patients with suspected focal liver lesions were enrolled in this study. All patients underwent the same standardized study protocol including HASTE and TrueFISP. A consensus reading based on all available image data served as a standard of reference for classifying lesions into cysts, hemangiomas, focal nodular hyperplasia, or malignant/other lesions. All malignant lesions, as well as hepatic adenomas and abscesses, were histologically verified. Each separated by an eight-week interval, HASTE and TrueFISP images were retrospectively reviewed in random order for the detection and characterization of focal hepatic lesions. Finally, a receiver operating characteristic (ROC) analysis was calculated. RESULTS: HASTE images had an overall sensitivity of 0.86 and a specificity of 0.91, whereas TrueFISP showed an overall sensitivity and specificity of 0.79 and 0.83, respectively (p>0.1). CONCLUSION: Neither HASTE nor TrueFISP alone are sufficient for the detection and characterization of hepatic lesions.

Female↗
PubMed2003

Using a 1 M Gd-chelate (gadobutrol) for total-body three-dimensional MR angiography: preliminary experience.

PURPOSE: To determine whether higher concentrated gadolinium chelates are advantageous for the recently introduced concept of total-body magnetic resonance angiography (MRA), allowing whole-body coverage, extending from the carotid arteries to the runoff vessels, in merely 72 seconds. MATERIALS AND METHODS: Total-body three-dimensional (3D) MRA using a 1 M Gd-chelate (gadobutrol, Gadovist, Schering, Berlin, Germany) at a dosage of 0.2 mmol/kg body-weight (biphasic injection protocol: 1.3 mL/second and 0.7 mL/second) was performed on three healthy volunteers and ten consecutive patients with DSA-documented peripheral vascular disease. Separated by at least 72 hours, the three healthy volunteers also underwent the same MRA-protocol, using gadopentetate dimeglumine in equimolar dosages. RESULTS: Compared to equimolar dosages, mean signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) values in the three volunteers were significantly higher (up to 32.5% for the arteries of the thighs and calves) using gadobutrol. In the ten patients, gadobutrol-based total-body MRA accurately assessed significant stenoses (luminal narrowing > 50%) with sensitivities and specificities of 96.2% (95% CI 0.83-0.97) and 95.7% (95% CI 0.84-0.96), respectively, compared to digital subtraction angiography. CONCLUSION: The MRA image quality for total-body MRA provided by the administration of gadobutrol is superior to that obtained following administration of an identical dose of gadopentetate dimeglumine, and therefore shows promise for use as a comprehensive single exam assessing the entire arterial system for the presence of atherosclerotic disease manifestations.

Adult↗
PubMed2003

Assessment of normal, inflammatory, and tumor-bearing lymph nodes with contrast-enhanced interstitial magnetic resonance lymphography: preliminary results in rabbits.

PURPOSE: To assess different gadolinium (Gd)-based contrast agents for interstitial magnetic resonance (MR) lymphography in normal, inflammatory, and tumor-bearing lymph nodes in rabbits. MATERIALS AND METHODS: Three paramagnetic contrast agents were assessed: a standard extracellular 0.5 M Gd-chelate, gadoterate meglumine (Gd-DOTA), and two macromolecular agents, P792 and P760 (all Guerbet, Aulnay-sous-Bois, France). A volume of 0.5 mL of each agent were injected subcutaneously into the dorsal footpads of six rabbits (three groups, 18 rabbits). Imaging was performed prior to as well as two weeks following induction of either reactive (complete Freund adjuvant) or tumorous (VX2 tumor) lymph nodes. T1-weighted three-dimensional gradient-echo and maximum intensity projection (MIP) images were obtained up to 120 minutes as well as 24 hours after administration of the different compounds. Signal-to-noise ratios (SNRs) of enhancing lymph nodes were calculated. The different compounds were compared regarding nodal enhancement over time, depiction of regional nodes, and lymphatic vessels. Furthermore, enhancement patterns were compared between normal, inflammatory, and metastasized nodes. RESULTS: Inguinal and iliac lymph nodes and lymph vessels revealed enhancement following interstitial injection of all evaluated compounds. For all agents, inflammatory lymph nodes revealed no significantly different SNRs compared to normal nodes (P > 0.2), whereas tumorous nodes showed signal voids and significantly lower SNRs (P < 0.05). Compared to P760 and P792, depiction of tumor-bearing nodes with Gd-DOTA was less reliable. CONCLUSION: Interstitial MR lymphography with P760 and P792 allows differentiation of tumor-bearing lymph nodes from reactive inflammatory and normal nodes based on a contrast uptake pattern assessed qualitatively as well as quantitatively.

Animals↗
PubMed2003

MR angiography of the chest.

Using the described strategies all relevant disease processes of the thoracic vessels can be fully depicted using contrast-enhanced three-dimensional MRA. The aorta and the major neck and arm vessels are well visualized. Vascular pathologies, such as aneurysms, dissections, and occlusions, are readily recognized. With the implementation of high-performance gradients, three-dimensional MRA of the pulmonary vasculature has become possible even in dyspneic patients. Congenital lesions, such as coarctations, are particularly well suited for analysis with these techniques.

Aorta↗
PubMed2003

Intraindividual comparison of gadopentetate dimeglumine, gadobenate dimeglumine, and gadobutrol for pelvic 3D magnetic resonance angiography.

RATIONALE AND OBJECTIVES: To compare the effect on image quality of a 1.0 mol/L gadolinium chelate with that of two 0.5 mol/L gadolinium compounds. MATERIALS AND METHODS: Five healthy volunteers underwent a mono-station 3D MRA exam (Siemens SONATA, Erlangen, Germany) four times using four separate gadolinium preparations. All subjects first received a fixed volume of undiluted gadobutrol (1 mol/L), which corresponded to a dose between 0.1 and 0.15 mmol/kg body weight. This gadobutrol dosage was then diluted with saline into twice the volume and administered as a bolus at twice the injection rate. For Gd-DTPA and Gd BOPTA, because these contrast agents are 0.5 mol/L preparations, the volume and flow rate were doubled to match diluted gadobutrol volume and concentration. Quantitative and qualitative analysis of the angiographic data sets was performed on nine arterial segments. RESULTS: Image quality was rated diagnostic for all image data sets without statistically significant differences between any of the compounds (P > 0.3). Quantitative measurements of Gd BOPTA (SNR: 81.15; CNR: 68.91) and both standard and diluted forms of gadobutrol (SNR: 84.33; CNR: 71.62; SNR(diluted): 79,23; CNR(diluted): 66.26) yielded significantly higher results (P < 0.02) in comparison with Gd-DTPA (SNR: 49.55; CNR: 38.24). The difference between either form of gadobutrol and Gd BOPTA was not shown to be statistically significant (P > 0.3), whereas both the SNR and CNR of standard gadobutrol were significantly higher than diluted gadobutrol. CONCLUSION: Gadobutrol- and Gd BOPTA-MRA exams lead to improved delineation of the pelvic arterial morphology compared with MRA exams performed with Gd-DTPA.

Adult↗
PubMed2003

Comprehensive time-resolved MRI of peripheral vascular malformations.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of MRI and MR angiography for the assessment of peripheral vascular malformations compared with the usefulness of conventional duplex sonography, venography, and arteriography. SUBJECTS AND METHODS. Nineteen patients (age range, 8-64 years; 11 males and eight females) with clinically diagnosed or suspected angiodyplastic abnormalities of the extremities were examined on a 1.5-T whole-body MR scanner. Using parameters based on a fast localizer sequence, we acquired transverse or coronal T1-, T2-, short tau inversion recovery (STIR), and contrast-enhanced T1-weighted images. Dynamic contrast-enhanced three-dimensional (3D) gradient-echo MRIs were acquired to determine the extent and type of the arteriovenous malformation for each patient. MR data sets were evaluated for lesion depiction, determination of the extent of the malformation, involvement of neighboring structures, vascular detail, and treatment planning. Results were compared with findings from duplex sonography, venography, and intraarterial digital subtraction angiography. RESULTS: All MRIs were of diagnostic quality and revealed 12 venous vascular malformations, four arteriovenous malformations, and three hemangiomas. The STIR sequence was helpful for determining the extent of the vascular malformation, which was often underestimated using contrast-enhanced 3D MR angiography alone, whereas dynamic contrast-enhanced 3D MR angiography was required for classifying the type of the lesion. MR angiography was inferior to conventional angiography for revealing vascular detail and for planning intervention. CONCLUSION: MRI and MR angiography appear to be valuable for the assessment of vascular malformations of the extremities. The protocol for imaging such malformations should combine dynamic contrast-enhanced 3D gradient-echo MRI with STIR sequences. However, digital subtraction angiography and venography are still required for definitive treatment decisions.

Adolescent↗
PubMed2002

Safety of contrast-enhanced MR angiography employing gadobutrol 1.0 M as contrast material.

Our objectives were to evaluate the safety of intravenous 1.0-M gadobutrol injections in patients with an indication for contrast-enhanced magnetic resonance angiography (CE MRA) of supra-aortal, pelvic, or peripheral arteries by examining and assessing adverse events, laboratory values, vital signs and ECG findings for clinical significance. In 435 patients, recruited in three multicenter trials for safety evaluations of the new contrast agent 1.0-M gadobutrol, CE MRA was performed with 1.0- to 1.5-T scanners using three-dimensional gradient-echo sequences and phased-array coils. The study population comprised 312 men and 123 women with a mean age of 60.9 years. Two hundred seven patients had an indication for imaging of body arteries and 228 had an indication for imaging of peripheral arteries. Blood laboratory values and urinalysis results of 124 patients as well as heart rate, blood pressure, and 12-lead-electrocardiogram readings of 93 patients obtained during a follow-up period of up to 72 h after the injection of contrast media were available for safety analysis. Contrast media application was performed as intravenous bolus injection of 1.0-M gadobutrol in fixed doses according to the patients' body weight (b.w.) and indication for CE MRA and was followed by a 20- to 40-ml saline flush. Mean dose actually applied was 0.1 0.27 mmol/kg b.w. Flow rate ranged between 0.2 and 2.0 ml/s. Safety evaluations found a good tolerability with only 4.6% of at least "possibly related" adverse reactions and no clinically relevant changes in blood and urine samples including no transmetallation effect on serum zinc values. Analysis of renal tolerance showed no influence on renal function irrespective of preexisting renal impairment. The ECG analysis (rhythm analysis, pace-setting disturbances, conduction disturbances, and time interval measurements, including uncorrected and corrected QT) showed no clinically relevant effect of the injection of 1.0-M gadobutrol on the cardiac conduction system. Intravenous injection of 1.0-M gadobutrol at a dose of up to 0.1 0.27 mmol/kg b.w. in the indication CE MRA is safe and causes no clinically relevant changes in safety parameters such as heart rate, blood pressure, blood and urine laboratory values, and cardiac conduction system.

Adult↗