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G Lutterbey

Publications and source records attributed to G Lutterbey.

At least 19 recordsLinked to original sources
PubMed2006

Initial experience with lung-MRI at 3.0T: Comparison with CT and clinical data in the evaluation of interstitial lung disease activity.

OBJECTIVES: We evaluated the feasibility of highfield lung-MRI at 3.0T. A comparison with Computed Tomography (CT) and clinical data regarding the assessment of inflammatory activity in patients with diffuse lung disease was performed. MATERIAL AND METHODS: Prospective evaluation of 21 patients (15 males, 6 females, 43-80 y) with diffuse lung diseases who underwent clinical work-up inclusive laboratory tests, lung-function tests and transbronchial biopsy. After routine helical CT (additional 12 HRCT) a lung-MRI (3.0 Intera, Philips Medical Systems, Best, The Netherlands) using a T2-weighted, cardiac and respiratory triggered Fast-Spinecho-Sequence (TE/TR=80/1500-2500 ms, 22 transverse slices, 7/2mm slice-thickness/-gap) was performed. A pneumologist classified the cases into two groups: A=temporary acute interstitial disease or chronic interstitial lung disease with acute episode or superimposed infection/B=burned out interstitial lung disease without activity. Two blinded CT-radiologists graded the cases in active/inactive disease on the basis of nine morphological criteria each. A third radiologist rated the MRI-cases as active/inactive, depending on the signal-intensities of lung tissues. RESULTS: The pneumologist classified 14 patients into group A and 7 patients into group B. Using CT, 6 cases were classified as active, 15 cases as inactive disease. With MRI 12 cases were classified as active and 9 cases as inactive. In the complete group of 21 patients MRI decisions and CT decisions respectively were false positive/false negative/correct in 2/4/15 respectively 0/8/13 cases. Correct diagnoses were obtained in 72% (MRI) respectively 62% (CT). In the subgroup of 12 cases including HRCT, MRI respectively CT were false positive/false negative/correct in 2/1/9 respectively 0/5/7 cases. Correct diagnoses were obtained in 75% (MRI) respectively 58% (CT). CONCLUSION: Highfield MRI of the lung is feasible and performed slightly better compared to CT in the determination of activity in patients with interstitial lung diseases.

Adult↗
PubMed2006

Is the body-coil at 3 Tesla feasible for the MRI evaluation of the painful knee? A comparative study.

The purpose of this study was to compare the in-built body coil of the 3.0-Tesla (T) scanner with a dedicated surface coil of a 1.5 T system regarding knee imaging. We performed an intraindividual prospective clinical trial on 17 patients with knee pain using magnetic resonance imaging (MRI) at 1.5 and 3.0 T systems equipped with identical gradient systems. Proton-density-weighted turbo spin echo sequences with the same spatial resolution and comparable contrast parameters were used. A quantitative measurement of signal to noise ratio (SNR), relative contrast (RC) and contrast to noise ratio (CNR) between muscle and bone marrow was performed, followed by a qualitative assessment of anatomic/pathologic structures and the extent of artefacts. At 3.0 T, 30 lesions (91%) compared to 33 lesions at 1.5 T were detected. The SNR/CNR/RC were moderately reduced at 3.0 T versus 1.5 T (muscle 42 vs 47 and bone 83 vs 112/46 vs 69/0.33 vs 0.43). Motion artefacts from the pulsating popliteal artery were significantly increased at 3.0 T. A visible and measurable signal loss occurred at 3.0 T using the built-in body coil compared with the dedicated 1.5 T knee coil, but nearly all clinically important information could be obtained.

Adult↗
PubMed2006

[Recurring, severe upper abdominal pain in a 45 year old patient].

A 45-year-old patient presented with a history of recurrent abdominal pain of unknown origin. The CT scan of the abdomen demonstrated a thickened mesenteric root and a segmental ileus of the jejunum. Laparotomy revealed a neuroendocrine tumour of the small bowel. Such tumours are rare causes of recurrent abdominal pain. Especially when the CT scan of the abdomen reveals mesenteric abnormalities (desmoplastic reaction) and/or a segmental ileus, a neuroendocrine tumour of the small bowel should be considered. The therapy of choice is resection of the tumour followed by systemic therapy including somatostain analogues and chemotherapy in the case of a hormone secreting tumour or metastases.

Abdominal Pain↗
PubMed2004

3.0-T high-field magnetic resonance imaging of the female pelvis: preliminary experiences.

The purpose of this study was to evaluate if 3.0 T allows for clinically useful pelvic magnetic resonance imaging, i.e. if familiar image quality and tissue contrast can be achieved at 3.0 T as compared with at 1.5 T. Adapting a 1.5-T protocol to the 3.0-T environment is subject to a variety of factors. In order to reduce the number of potential variables, we chose two cornerstones: the 3.0-T sequence should have similar spatial resolution and acquisition time; furthermore, the contrast parameters repetition time (TR) and echo time (TE) were kept identical. Based on this modified 3.0-T T2-weighted turbo spin-echo sequence (TR/TE 2,705/80 ms; 0.7x1.04x4 mm measured voxel size; field of view 360 mm; 4.03-min scan time) we performed an intraindividual study on 19 patients with the 1.5-T sequence as the standard of reference. Two radiologists analyzed the examinations in consensus with regard to tissue contrast (visualization of zonal anatomy of the uterus and/or delineation of pathologic findings) rated on a three-point scale (3 is 3.0 T better; 2 is 3.0 T equal; 1 is 3.0 T worse than 1.5 T). In addition, the signal difference between muscle and bone marrow was measured as a marker for tissue contrast. The analysis of the image quality comprised the level of the artifacts (rated on a five-point scale: 1 is no artifacts; 5 is nondiagnostic study), the visual signal-to-noise ratio (rated on a three-point scale) and detail delineation. Only minor artifacts were observed at both 1.5 and 3.0 T; the difference was not statistically significant. The visual signal-to-noise ratio and the delineation of image details were rated equal for 1.5 and 3.0 T. With regard to image contrast, both qualitative analysis as well as quantitative analysis revealed comparable image contrast for the 1.5- and 3.0-T protocols. Pathological findings were seen equally well with both field strengths. Clinically diagnostic pelvic studies of high image quality can be obtained using a 3.0-T scanner with our modified examination protocol. To fully exploit the capability of the high-field technique, and to point out potential advantages, further intraindividual studies are needed, with the adjustment of other imaging parameters to the high-field environment.

Adult↗
PubMed2004

Lung MRI at 3.0 T: a comparison of helical CT and high-field MRI in the detection of diffuse lung disease.

The purpose of this study was to evaluate the feasibility of high-field magnetic resonance imaging (MRI) of the lung using a T2-weighted fast-spin echo (TSE) sequence. Comparison was made with helical computed tomography CT findings in patients with diffuse pulmonary diseases. Prospective segment-wise analysis of high-field MR imaging findings in 15 patients with diffuse pulmonary diseases was made using helical CT and HRCT as the standard of reference. The MR studies were performed on a 3.0-T whole body system (Intera 3T, Philips Medical Systems) using a T2w TSE sequence with respiratory and cardiac gating (TE 80 ms TR 1,500-2,500 ms; turbo factor 17; 22 slices with 7/2-mm slice thickness and gap; 256x192 matrix). MR artifacts were graded on a three-point scale (low, moderate, high). Lung MR studies were prospectively analyzed segment-by-segment and diagnosed as healthy or pathological; results were compared with helical CT findings. In all 15 patients, MR imaging of the lung was successful. All 15 MR studies were compromised by artifacts; however, the severity of these artifacts was classified as low or moderate in 8/15, respectively, 7/15 cases. A total of 143/285 lung segments showed diffuse lung disease in helical CT. With MRI, 133 of these 143 segments (93%) were judged to be diseased. The ten segments that received false negative MR diagnoses displayed non-acute pulmonary lesions with inherently low proton density (scars, granulomas). MRI at 3.0 T can detect diffuse pulmonary disease with a high sensitivity. Based on this experience, further pulmonary studies with high-field systems appear justified and promising.

Adult↗
PubMed2000

MR imaging of pneumonia in immunocompromised patients: comparison with helical CT.

OBJECTIVE: A T2-weighted turbo spin-echo sequence was compared with CT in immunocompromised patients with opportunistic pneumonia. SUBJECTS AND METHODS: Sixteen patients with pneumonia shown on helical CT were examined using MR imaging within 2 days. MR examinations were performed on a 1.5-T system with a transversal T2-weighted ultrashort turbo spin-echo sequence using expiratory gating and diastolic triggering. Two radiologists reviewed the MR and CT images independently. The number, localization, and morphology of lesions were noted. MR image quality was rated using a 4-point scale. RESULTS: The results of the CT and MR examinations concerning the number and morphology of pulmonary lesions caused by pneumonia were identical in 75% of the patients (n = 12). MR imaging was able to depict all typical features of pneumonia including different stages of parenchymal infiltration (ground-glass versus consolidation). MR imaging depicted early necrotizing pneumonia not shown on contrast-enhanced CT in 25% of the patients (n = 4); 82% of the MR examinations were rated as excellent (1 point) or good (2 points). CONCLUSION: T2-weighted turbo spin-echo imaging is able to depict characteristic features of pneumonia and shows excellent results compared with CT. This MR technique offers advantages in patients with pneumonia because of its higher sensitivity for necrotizing pneumonia.

Adolescent↗
PubMed1999

[MRT versus CT in the diagnosis of pneumonias: an evaluation of a T2-weighted ultrafast turbo-spin-echo sequence (UTSE)].

PURPOSE: To evaluate a T2-weighted URSE sequence for the assessment of pulmonary infiltrations in comparison to CT. METHODS: 28 MRT scans of 22 patients with confirmed pneumonia were recorded on a 1.5 Tesla apparatus with an expiratory and diastolic triggered, T2-weighted ultrafast-spin-echo sequence in axial slice mode with the following parameters: TReff/TE/Turbo-factor 2000-4000/90 ms/21-23; slice thickness/separation 6/0.6 mm; FOV 360 mm; 24 slices. 24 spiral CTs (since thickness/table advance: 1-2 mm/10mm) were available for comparison. The separate evaluation of MRTs and CTs was performed by three radiologists in a consensus procedure with regard to pulmonary lesions (e.g., infiltration, round foci, net patterns) and image quality of the MRTs (4-step scale). RESULTS: In 71% of the cases the CTs and MRTs agreed with the diagnosis and representation of the lesions, in 25% MRT was superior. MRT was better for the detection of pulmonary abscesses. In 93% the image quality of the MRT was very good to good. CONCLUSIONS: MRT in the technique presented here is in most cases equal to CT for the detection of pneumonia. Diagnosis of pulmonary abscesses seems to be better with MRT.

Adult↗
PubMed1998

[A rational study of the great abdominal veins using 2D-TOF- and turbo-spin-echo sequences].

PURPOSE: Development of a fast and reliable protocol for the detection and exclusion of abdominal venous thrombosis with an optimised T2-TSE- and 2D-TOF sequence. MATERIAL AND METHOD: Evaluation of the flow-void phenomenon with a flow phantom on a 1.5 and 0.5 Tesla system using different echo times. Examination of 22 patients with suspected abdominal shunt- or abdominal vein-thrombosis with a optimum T2-TSE- and 2D-TOF sequence with a 1.5 or 0.5 Tesla system. Confirmation of thrombosis with contrast-enhanced computed tomography or digital subtraction angiography. RESULTS: The most effective combination of strong flow-void phenomena, signal/noise ratio and scan time was found with the following parameters: TE 120 ms, TR 2000 ms, 5 mm slice gap. In the patient group two complete and two partial thromboses were diagnosed with both sequences. One wrong positive thrombosis occurred in a stenotic anastomosis with the 2D-inflow sequence. CONCLUSION: With optimum parameters the T2-TSE sequence produces a strong "flow-void" phenomenon suitable for "black-blood"-MRA. The use of this sequence alone or in combination with 2D-inflow MRA, if "bright-blood" MRA is recommended, allows a reliable evaluation of thrombosis in abdominal veins without high-tech MRA equipment and contrast media.

Abdomen↗
PubMed1998

[Detection of focal lung lesions with magnetic resonance tomography using T2-weighted ultrashort turbo-spin-echo-sequence in comparison with spiral computerized tomography].

PURPOSE: To compare spiral CT and MRT for the detection of focal pulmonary lesions. PATIENTS AND METHODS: 50 patients with focal pulmonary lesions confirmed by spiral CT were examined using a T2-weighted UTSE sequence (TE: 90 ms, TR: 1500-3000 ms, echo interval 9 ms, 8 mm slice thickness, diastolic triggering, expiratory breath gating). Image quality was compared using a 4-stage scale. Lesions with a minimum size of 2 mm were counted and measured in the CT image. The results were compared with the MRT images. RESULTS: The image quality in CT examinations with an average value of 1.22 better than that in MRT (1.78). In total 163 pulmonary lesions with a size of 2-115 mm were found by CT. MRT found 151/163 lesions (92.6%). Of the 12 lesions not detected, 9 were smaller than 4 mm, 1 corresponded to a 12 mm large, completely calcified granuloma. In 2 cases there was a 4 or 5 mm large unspecific scar. Thus, 160/163 (98.1%) of all lesions larger than 3 mm were detected. CONCLUSIONS: MRT with use of a suitable UTSE sequence is an alternative to CT for the detection of focal pulmonary lesions with a size larger than 3 mm.

Adolescent↗
PubMed1997

[Indirect MR arthrography in the diagnosis of lesions of the labrum glenoidale].

PURPOSE: It has been shown that intravenous administration of contrast media produces an MR arthrographic effect without the need for intraarticular injection. This is the first study evaluating this new technique of indirect MR arthrography in the diagnosis of glenoid labrum tears. METHODS: 28 patients with clinically suspected labral injuries were prospectively investigated (1.5 Tesla, flexible surface coil). A plain MR examination of the shoulder (transverse and oblique-coronal orientation, T1-weighted spin- [TE/TR 15/675], proton density- and T2*-weighted gradient echo [TE/TR/Flip 14,32/600/30 degrees] sequences) and indirect MR arthrography (transverse and oblique-coronal orientation, fat-suppressed T1-weighted spin-echo sequences [TE/TR 15/675], intravenous injection of gadopentetate dimeglumine [0.1 mmol/kg], followed by 10-15 min of joint movement) were performed. Results were confirmed by arthroscopy and/or open surgery. RESULTS: Indirect MR arthrography significantly improved delineation of the glenoid labrum and hyaline cartilage (p < 0.05). Sensitivity and specificity of indirect MR arthrography in the diagnosis of labral injuries were 90% and 89%, compared to 79% and 67% of the native MR examination. CONCLUSION: Indirect MR arthrography is a promising non-invasive technique in the evaluation of the glenoid labrum.

Adult↗
PubMed1997

Healthy premenopausal breast parenchyma in dynamic contrast-enhanced MR imaging of the breast: normal contrast medium enhancement and cyclical-phase dependency.

PURPOSE: To define the range of normal contrast medium enhancement, the variability in contrast medium enhancement patterns in healthy premenopausal breast parenchyma, and the implications for management strategies in cases with incidental contrast medium-enhancing foci on breast magnetic resonance (MR) images. MATERIALS AND METHODS: Twenty healthy volunteers (aged 21-41 years) were examined on a 1.5-T system (dynamic two-dimensional gradient-echo protocol with subtraction postprocessing) during each week of a menstrual cycle (group 1) or over 4 months (group 2). The authors evaluated changes in the number of enhancing foci and the respective enhancement patterns within a cycle and between cycles. RESULTS: Both diffuse and nodular enhancement of breast parenchyma occurred during all phases of the menstrual cycle, especially in weeks 1 and 4. Enhancement was lowest in week 2. A total of 60 enhancing foci (73% of which resolved completely during follow-up) were found in 16 of 20 volunteers. Twenty-six foci demonstrated enhancement velocities beyond the malignancy threshold (>80% increase in the 1st minute). CONCLUSION: Contrast-enhancing foci are normal in healthy premenopausal breasts, even when formal malignancy criteria of enhancement velocity are met. This has to be kept in mind to avoid false-positive results, especially in younger patients.

Adult↗
PubMed1996

[A new application of MR tomography of the lung using ultra-short turbo spin echo sequences].

PURPOSE: Development of an improved MR sequence for examining the lung. METHOD: T2 weighted ultra-short turbo spin echo sequences were used in five individuals with variations in echo times, delayed triggering and echo intervals. To reduce movement artifacts all examinations were carried out with ECG and respiratory triggering. The sequences giving optimal image quality were then employed in 19 patients having various pulmonary abnormalities. Image resolutions, artifacts, image contrasts and diagnostic value were then judged by two observers and compared with CT. RESULTS: In the first study, a diastole-triggered UTSE sequence with the shortest echo proved optimal (TE = 90 ms, TR = 2-4 s, echo = 9 ms, turbo factor = 19). In the patient series studied, MRT was inferior to CT with regard to resolution and number of artifacts, but better in respect of contrast and diagnostic value. CONCLUSION: Using UTSE of the lung, MRT can produce images of good quality. Compared with CT, contrast is better with MRT, offering diagnostic advantages for MRT.

Diagnosis, Differential↗
PubMed1996

[Standardization and acceleration of quantitative analysis of dynamic MR mammographies via parametric images and automatized ROI definition].

PURPOSE: To evaluate quantitative analysis of dynamic breast MRI studies using a dedicated PC based diagnosis system (DS) providing parametric images and automatic ROI definition as compared to the standard subtraction image, manual-ROI based procedure. METHODS: We compared the diagnostic usefulness of parametric versus subtraction images in terms of visualisation of enhancement inhomogeneities and enhancement velocities. Quantitative analysis of enhancing lesions of 15 breast MRI studies was performed using both the DS and the system's console software (SC). We assessed the time needed for complete quantitative analysis and number of lesions evaluated. This was followed by assessment of within-reader and between-reader variability or within-case reproducibility of results of quantitative analysis. RESULTS: Parametric images are superior to subtraction images in visualizing enhancement inhomogeneities or ring enhancement in breast cancers. Mean time needed for analysis at DS and SC was 4 (3-5) min. and 23 (8-39) min., respectively. During this time period, significantly more lesions were evaluated per case using the DS as compared to the SC (2-14 vs. 1-6). Mean within-reader variability of enhancement velocities of the same lesions was 0% and 25% (DS and SC); between-reader variability of enhancement values obtained in the same lesions was 11% (DS) versus 41% (SC). CONCLUSION: The DS significantly cuts down the time needed for quantitative analysis. It significantly improves reproducibility of quantitative enhancement values due to standardization of ROI analysis.

Adult↗
PubMed1996

[Intramural hematoma of the thoracic aorta: diagnostic imaging and differential diagnosis].

PURPOSE: Aortic wall thickening due to intramural hemorrhage may be the only sign of aortic dissection. The aim of this study was to evaluate the incidence, imaging features and differential diagnoses of intramural hemorrhage (IMH) of the thoracic aorta. METHODS: 98 patients with clinically suspected aortic dissection were investigated via Spiral-CT and MRT. Diagnosis of IMH based on the presence of smooth crescentic or concentric wall thickening over a longer segment of the thoracic aorta without flow visualization and without compression or distortion of the aortic lumen. RESULTS: 69 patients had classic aortic dissections and 7 patients were diagnosed to have IMH of thoracic aorta. One patient with IMH of the ascending aorta died of aortic rupture and subsequent pericardial tamponade 12 hours after onset of symptoms. In one patient with IMH of the descending aorta on initial examination, there was a progression of overt aortic dissection at follow-up after three weeks. In two patients with IMH of the descending aorta, wall thickening decreased in size at follow-up (10-15 weeks), whereas in one patient it remained unchanged. CONCLUSION: IMH of the aorta should be considered a precursor of aortic dissection. At follow-up IMH may decrease in size, rupture or progress to overt aortic dissection.

Adult↗
PubMed1996

Aortic dissection: a comparative study of diagnosis with spiral CT, multiplanar transesophageal echocardiography, and MR imaging.

PURPOSE: To compare the usefulness of spiral computed tomography (CT), multiplanar transesophageal echocardiography (TEE), and magnetic resonance (MR) imaging in the diagnosis of thoracic aortic dissection and arch vessel involvement. MATERIALS AND METHODS: Forty-nine symptomatic patients with clinically suspected aortic dissection were examined with contrast material-enhanced spiral CT, multiplanar TEE, and 0.5-T MR imaging (T1-weighted, cardiac-gated, spin-echo sequences). Imaging results were confirmed at autopsy (five patients), intraoperative exploration (23 patients), angiography (nine patients), and follow-up (12 patients). RESULTS: Sensitivity in the detection of thoracic aortic dissection was 100% for all techniques. Specificity was 100%, 94%, and 94% for spiral CT, multiplanar TEE, and MR imaging, respectively. In the assessment of aortic arch vessel involvement, sensitivity was 93%, 60%, and 67%, respectively, and specificity was 97%, 85%, and 88%, respectively. CONCLUSION: Spinal CT and multiplanar TEE are as valuable as MR imaging in the detection of thoracic aortic dissection. In the assessment of the supraaortic branches, spiral CT is superior (P<.05).

Adult↗
PubMed1995

[Value of Turbo-FLAIR sequence in the diagnosis of brain diseases at 0.5 tesla].

PURPOSE: Aim of the study was to evaluate FLAIR combined with Turbo-Spin-Echo (Turbo-FLAIR) at 0.5 tesla in comparison to conventional T1- and T2-weighted spin-echo images (SE) in MRI of the brain. MATERIAL AND METHODS: A Turbo-FLAIR sequence was optimised for 0.5 Tesla (Philips Gyroscan T5-II) that provided seventeen 5 mm sections in 4:21 minutes (TR = 6075 ms, T1 = 1600 ms, TE = 120 ms and a turbofactor = 17). Images were compared with T1- (TR = 500 ms, TE = 15 ms) proton density and T2-weighted spin-echo (TR = 2500 ms, TE = 20/90 ms) studies in 10 healthy volunteers and 30 patients with various brain pathologies. RESULTS: Turbo-FLAIR could effectively eliminate the CSF signal in all studies except ventricular areas with CSF inflow. Contrast-to-noise ratios (C/N) for the contrast between lesions and CSF was superior in Turbo-FLAIR. C/N between lesions and grey matter was significantly higher in Turbo-FLAIR than in proton density (PD)-weighted SE. C/N between lesions and white matter was equal to PD-weighted SE but significantly smaller than on T2-weighted SE. Visual analysis showed greater lesions conspicuity with Turbo-FLAIR and a higher frequency of detection of cortical and subcortical lesions. CONCLUSIONS: Turbo-FLAIR is a reliable and practical technique on 0.5 Tesla, that is more sensitive than SE sequences especially for the detection of cortical, subcortical lesions and lesions surrounded by CSF.

Adolescent↗