PubMed Health⌕ Search

Biomedical subjects

M Steinborn

Publications and source records attributed to M Steinborn.

27 records · Page 2Linked to original sources
PubMed1998

Parametrial invasion in cervical carcinoma: evaluation of detection at MR imaging with fat suppression.

PURPOSE: To evaluate detection of parametrial invasion at magnetic resonance (MR) imaging with fat suppression. MATERIALS AND METHODS: In 35 patients with cancer of the cervix, MR imaging was performed with the following sequences: T2-weighted turbo spin echo (SE), turbo short inversion time inversion recovery (STIR), and unenhanced or gadolinium-enhanced T1-weighted SE with and without excitation-spoiling fat suppression. Images obtained with each sequence were evaluated for parametrial invasion by two blinded radiologists separately, who scored their level of diagnostic confidence from 0 to 10 (no confidence to high confidence). Then, all images were evaluated together and findings were correlated with histopathologic findings. RESULTS: No statistically significant differences were found between staging with T2-weighted turbo SE, turbo STIR, and T1-weighted fat-suppressed gadolinium-enhanced SE images. Staging with T1-weighted SE, T1-weighted gadolinium-enhanced SE, and T1-weighted fat-suppressed SE images was significantly worse (P < .05). Diagnostic confidence was lower (P < .001) with T1-weighted gadolinium-enhanced SE and T1-weighted fat-suppressed gadolinium-enhanced SE images (5.5 and 6.2 points, respectively) compared to staging with T2-weighted turbo SE and turbo STIR images (8.2 and 7.6 points, respectively). No statistically significant improvement in staging accuracy was found when all images were evaluated together. CONCLUSION: In MR diagnosis of parametrial invasion, the addition of fat-suppressed or gadolinium-enhanced MR images did not improve the accuracy with T2-weighted turbo SE images alone.

Cervix Uteri↗
PubMed1998

Lateral ankle ligaments and tibiofibular syndesmosis. 13-MHz high-frequency sonography and MRI compared in 20 patients.

To test the ability of ultra-high frequency ultrasound (13 MHz scanner) to distinguish between intact and ruptured ligaments on the lateral side of the ankle, we examined 20 patients with an acute inversion injury with MRI and ultrasound. When judged by the MRI diagnosis, an injured anterior talofibular ligament was correctly diagnosed by ultrasound in 13 of 14 and an intact anterior talofibular ligament in 5 of 6 patients. In the case of the calcaneofibular ligament, 4 ruptured and 16 intact ligaments were diagnosed equally well with both methods. The injured anterior tibiofibular ligament was correctly diagnosed by ultrasound in 6 of 9 patients, while the intact ligament was correctly recognized in 10 of 11 patients. Our findings indicate that it is possible to distinguish injured from intact ligaments sonographically.

Fibula↗
PubMed1998

Magnetic resonance imaging and knee stability following ACL reconstruction.

This study was undertaken to determine whether there is a correlation between magnetic resonance imaging (MRI) and clinical success after reconstruction of the anterior cruciate ligament (ACL). In a prospective study, 28 patients underwent clinical and MRI examination 3 to 5 years after ACL reconstruction with either the semitendinosus tendon (n = 15) or patellar ligament (n = 13). Knee stability was assessed both clinically and by KT-1000 arthrometer testing. Magnetic resonance imaging was performed with a 0.2-T dedicated system (Artoscan, Esaote, Italy) including sagittal and oblique coronal T1 and T2-weighted images. Magnetic resonance images were evaluated by two readers with regard to signal intensity and continuity of the ACL reconstruction and presence or absence of posterior cruciate ligament buckling. Knee stability and MRI evaluation were each summarized in a 6-point score. Statistical correlation was checked with the Spearman ranked correlation for testing non-normal distributed samples. Statistical testing of all patients' results together showed a significant correlation with a prediction value of 12%, indicating no significant correlation between clinical results and MRI evaluation. Separate statistical testing of the patellar ligament and semitendinosus patients' results showed no significant correlation in either group at all. Thus, no correlation between clinical stability and MRI could be established. Magnetic resonance images after ACL reconstruction using the techniques mentioned above should be interpreted with caution, as they may not relate to the clinical function of the ligament.

Adolescent↗
PubMed1997

[Examination of the hand and wrist joints with a dedicated low-field MRI device].

Purpose of this study was to evaluate the diagnostic value of a low field dedicated MRI system in hand and wrist imaging. All 308 exams of the hand and wrist, that were performed on a low-field dedicated MRI system (Artoscan, Esaote Biomedica, Italy) in our institution in 1996, and high-field MRI exams performed in addition as part of the diagnostic work-up, were evaluated and correlated to final operative (n = 64) and histologic (n = 12) reports. 90% of all low-field MRI scans stated a diagnosis according to clinical suspicion. In 62% the clinical question was answered, and in 26% additional pathologies were identified. An MR-diagnosis completely different from the clinical suspicion was stated in 2%. High field exams contributed additional information in 6 of 36 patients. In 3 patients a tumor was not shown completely in the limited field-of-view of the dedicated low-field MRI-system. Frequency-selective fat-suppression pulse sequences and a better spatial resolution were the reasons for the additional information obtained in the other three patients. Low-field dedicated MR-imaging is a valuable method in the extensive work-up of the hand and wrist. Osseous, ligamentous and tendinous pathologies are well depicted. Large or infiltrative tumors should be referred to a high-field system.

Adolescent↗
PubMed1997

[Lymph node staging in cervix carcinomas: the results of high-resolution magnetic resonance tomography (MRT) with a phased-array body coil].

PURPOSE: To determine the diagnostic value of high resolution MR imaging with a circularly polarised (c.p.) body phased-array coil for the staging of pelvic lymph nodes in cervical carcinoma. MATERIAL AND METHODS: 42 patients with histologically proven carcinoma of the cervix were studied on a 1.5 T scanner by using a c.p. body phased-array coil. The imaging protocol included T2-weighted turbo-spin-echo (TSE) and T1-weighted spin-echo sequences pre and post i.v. application of Gd-DTPA; slice thickness was 5-7 mm and pixel size 0.53 mm2. Lymph nodes with a diameter of > or = 8 mm were considered to have metastatic involvement. MR imaging results were compared with histopathologic findings. RESULTS: MR imaging showed enlarged lymph nodes (> or = 8 mm) in 16 of 18 patients with histologic proof of lymph node metastases (sensitivity 89%). In 22 of 24 cases MR findings were true negative (specificity 92%). Diagnostic accuracy was 91%. CONCLUSION: High-resolution MR imaging with a c.p. body phased-array coil provides high sensitivity, specificity, and diagnostic accuracy for pelvic lymph node staging in cervical carcinoma.

Adult↗
PubMed1994

[MR angiography of the heart and thoracic blood vessels. Use of rapid ECG-triggered techniques with multiplanar reconstruction capability].

Segmented 2D times-of-flight (TOF) magnetic resonance angiography (MRA) with ECG gating is a suitable adjunct to conventional magnetic resonance tomography. Based on our experience with 106 patients, cardiovascular MRA primarily aids in the diagnosis of congenital heart disease, but is of minor importance for the evaluation of acquired cardiovascular disease, such as aortic aneurysms. Changes in flow dynamics as a result of spin dephasing may render partial signal loss. Due to flow turbulence and resulting signal loss distal to stenoses, difficulties may arise in correctly determining the degree of stenosis and differentiating between partial thrombosis and slowly flowing blood. The most promising approach for optimizing 2D TOF MRA is enhancement of the intravascular signal and suppression of background signal. For the equipment we use with a 0.5 Tesla scanner, the most powerful combination to enhance intravascular signal and suppress back-ground noise was applying a flip angle of 65 degrees and a short inversion prepulse. The influence of the flip angle and prepulse on the intravascular signal varies, dependent on the flow velocities and heart rates. Secondary reconstructions, such as the MIP technique, contribute to better spatial orientation by using rotating projection views. To avoid overprojection artifacts and loss of diagnostic information, 2D single slices should be the primary source of image analysis.

Aortic Diseases↗
PubMed1982

Teaching an autistic child pedestrian skills.

An autistic child was taught pedestrian skills in a classroom by use of a model of the streets and the intersection she most often frequented. She manipulated a doll and verbalized what the doll was doing to get to the designated location. After mastering the pedestrian skills on the model, video recordings familiarized her with traffic at local intersections. She successfully generalized the pedestrian skills to the natural environment.

Accident Prevention↗
PubMedDate not supplied

MR angiography of congenital heart disease: value of segmented two-dimensional inflow technique and maximum-intensity-projection display.

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40-50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65 degrees and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.

Aorta↗