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1.
Eur Radiol ; 16(6): 1237-43, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16447048

ABSTRACT

Thirty-seven consecutive patients with elevated PSA levels and negative tumor prostate biopsies underwent a MR-guided prostate biopsy in a 1.5-T scanner in the supine position. After localization of suspected tumor areas using an endorectal coil and two body-phased array coils, the biopsy device was positioned without any repositioning of the patient. The biopsy device consisted of a mount, a ball joint, a positioning stage and an insertion stage with a needle guide, which was filled with a MR-visible fluid to control positioning of the needle using a balanced steady-state free precession sequence (TrueFISP) and a high-resolution turbo spin echo (T2-TSE) sequence. Core biopsies were taken manually in the magnet. The biopsy needle could be correctly positioned in all cases. Suspected lesions with a diameter > or =10 mm could be successfully punctured. Four to nine (mean = 6) biopsies were taken per patient. In 14 patients, prostate cancer was confirmed at histology. Twenty-four biopsies positive for cancer were performed in 14 patients. A correct correlation was found between the site of biopsy and histology. MR-guided prostate biopsy can be effective in increasing primary positive tumor biopsy results in patients with a history of negative tumor TRUS-guided prostate biopsies.


Subject(s)
Biopsy, Needle/methods , Magnetic Resonance Imaging/methods , Prostate/pathology , Radiology, Interventional/methods , Supine Position , Adenocarcinoma/pathology , Aged , Biopsy, Needle/instrumentation , Contrast Media , Equipment Design , Humans , Image Enhancement/methods , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/instrumentation , Male , Middle Aged , Prostate-Specific Antigen/analysis , Prostatic Hyperplasia/pathology , Prostatic Neoplasms/pathology , Prostatitis/pathology
2.
Eur Radiol ; 14(1): 99-105, 2004 Jan.
Article in English | MEDLINE | ID: mdl-12845463

ABSTRACT

The aim of this study was presentation of a whole-body MRI technique with a moving table as a screening tool for bone metastases in patients with breast cancer. Twenty-two patients with breast carcinoma underwent both a planar whole-body bone scintigraphy and whole-body MRI at 1.5 T. The MRI images were acquired with a moving table at six different anatomical positions within a measurement time of 20 min. Coronal images were acquired using a short-tau inversion recovery sequence, accomplished by an axial T2-weighted turbo-spin-echo sequence through the head, and a T1-weighted opposed-phase sagittal 2D fast low-angle shot sequence covering the whole spine. The MRI findings indicating bone metastases were compared with findings from bone scintigraphy. Metastatic lesions were confirmed by follow-up examinations over 1 year. Twelve patients showed bone metastases. Whole-body MRI was superior to bone scintigraphy in predicting lesion origin with a sensitivity of 92% (bone scintigraphy 83%), a specificity of 90% (scintigraphy 80%) and an accuracy of 91% (scintigraphy 82%). The MRI showed additional findings such as metastases of the lung and liver. Whole-body MRI with moving table technique may be an effective method of total body screening for bone in selected patients with breast carcinoma and a high risk of distant metastases, although with the higher costs of MRI bone scintigraphy must still be considered as the first method for screening patients with breast cancer.


Subject(s)
Bone Neoplasms/diagnosis , Bone Neoplasms/secondary , Breast Neoplasms/pathology , Magnetic Resonance Imaging/methods , Radiographic Image Enhancement , Radionuclide Imaging/methods , Aged , Aged, 80 and over , Breast Neoplasms/surgery , Cohort Studies , Female , Follow-Up Studies , Humans , Middle Aged , Neoplasm Invasiveness/diagnostic imaging , Neoplasm Invasiveness/pathology , Neoplasm Staging , Risk Assessment , Sensitivity and Specificity , Technetium Tc 99m Medronate
3.
Eur Radiol ; 10(12): 1947-53, 2000.
Article in English | MEDLINE | ID: mdl-11305577

ABSTRACT

The aim of this study was to predict the benign or malignant nature of a prostatic lesion by defining a threshold value of signal intensity ratio and a limiting value of serum prostate-specific antigen (PSA) in patients with elevated PSA level. Twenty-six patients with elevated PSA level and no hypoechogenic lesions at endosonography underwent MR imaging using an endorectal body phased-array coil at 1.5 T (Siemens Magnetom Symphony). A T2-weighted turbo-spin-echo (TSE) pulse sequence was applied in a transverse orientation. Two radiologists evaluated the images. In the presence of a pathological finding they defined regions of interest (ROI) in the suspicious pathological area of the peripheral zone and in muscle for reference. The quotient of the two ROIs was calculated and then correlated with the actual PSA level. Diagnosis was confirmed by prostate biopsy. Ten of 12 patients with quotients smaller than 4 showed cancer at histology. Nine of 12 men with cancer proven by biopsy had PSA levels higher than 10 ng/ml. A significant difference (p < 0.001) was found between the quotients of cancer and quotients of chronic prostatitis, fibrosis, or glandular atrophy. The accuracy of tumor differentiation of the method was 77%. Measurement of signal intensity quotients in the peripheral zone of the prostate in combination with knowledge of defined limits of PSA levels the technique could be helpful in detecting additional cancer areas for prostate biopsy. False-negative tumor results of standard sextant biopsy can be reduced. In men with high PSA values the method has a role in differentiating between patients who require prostate biopsy and those of clinical observation.


Subject(s)
Magnetic Resonance Imaging , Prostate-Specific Antigen/blood , Prostate/pathology , Prostatic Neoplasms/diagnosis , Adult , Aged , Biopsy, Needle , Diagnosis, Differential , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Sensitivity and Specificity
5.
Eur Radiol ; 7(5): 643-8, 1997.
Article in English | MEDLINE | ID: mdl-9166559

ABSTRACT

A total of 18 patients with clinical suspicion of a pancreatic tumor underwent dynamic contrast-enhanced CT and MRI examinations. A fat-suppressed T1-weighted 2D fast-low-angle-shot (FLASH) sequence and a T2-weighted spin-echo (SE) sequence were applied in a transverse orientation using a circularly polarized (CP) body phased-array coil. The FLASH sequence was repeated after Gd-DTPA administration. The highest spatial resolution was 1.37 x 1.37 x 3.00 mm3. In two cases a half Fourier single-shot turbo-SE sequence (HASTE) was additionally applied. In a comparison between CT and MRI, pancreatic masses could be demonstrated and characterized with excellent image quality. The fat-saturated 2D FLASH sequence yielded the highest contrast-to-noise ratios after Gd-DTPA administration between pancreas and inflammatory or neoplastic lesion. One non-contour deforming carcinoma could be detected only with MRI and was only retrospectively visible on CT with an element of uncertainty. Magnetic resonance imaging using a CP body phased-array coil and fat-suppressed T1- and T2-weighted FLASH, SE, and turbo-SE sequences offers diagnostic possibilities in improved imaging of the pancreas.


Subject(s)
Magnetic Resonance Imaging/instrumentation , Pancreas/pathology , Pancreatic Neoplasms/diagnosis , Aged , Contrast Media , Female , Gadolinium , Gadolinium DTPA , Humans , Magnetic Resonance Imaging/methods , Male , Organometallic Compounds , Pancreatic Diseases/diagnosis , Pentetic Acid/analogs & derivatives , Tomography, X-Ray Computed
6.
Eur Radiol ; 7(5): 737-42, 1997.
Article in English | MEDLINE | ID: mdl-9166575

ABSTRACT

Conventional myelography was compared with a new type of MR technique using a fat-suppressing 3D fast imaging with steady precession (FISP) sequence for diagnosis of the lumbar root compression syndrome. 80 patients with discogenic disease in the lumbar spine were examined with a 1.0-T whole-body MR system (Siemens Magnetom Impact, Erlangen, Germany). A strongly T2(*)-weighted 3D FISP sequence was applied in the sagittal orientation. To obtain fat suppression, a frequency-selective 1-3-3-1 prepulse was applied prior to the imaging sequence. The acquired 3D data set was evaluated using a maximum intensity projection (MIP) program. The measurement time was 7 min, 47 s. Magnetic resonance myelography has significant advantages over conventional myelography, particularly in cases of extreme spinal canal stenosis. Compared with the conventional method, this new MR technique shows comparable sensitivity in the visualization of the spinal nerve roots in the lumbar spine.


Subject(s)
Intervertebral Disc Displacement/diagnosis , Lumbar Vertebrae/pathology , Magnetic Resonance Imaging/methods , Myelography , Nerve Compression Syndromes/diagnosis , Spinal Nerve Roots/pathology , Spinal Stenosis/diagnosis , Case-Control Studies , Female , Humans , Image Processing, Computer-Assisted , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged , Sensitivity and Specificity , Spinal Nerve Roots/diagnostic imaging
7.
Eur Radiol ; 7(9): 1485-91, 1997.
Article in English | MEDLINE | ID: mdl-9369519

ABSTRACT

The aim of this study was to compare a new MRI method for detecting the existence of cerebrospinal fluid (CSF) fistulae, i. e. MR cisternography, with CT cisternography. In a prospective study, 30 patients with post-traumatic CSF fistulae were examined. The MR examinations were performed with a 1.0-T whole-body MR system, using two T2(*)-weighted sequences, a 3D PSIF (time-inversed fast imaging with steady-state precession, FISP) and a 3D constructive interference steady-state (CISS) sequence. The results of MRI and CT cisternography were compared with the surgical findings. The sensitivity in detecting CSF fistulae with MR cisternography (PSIF: 89.9 %; CISS: 93.6 %) was higher than with CT cisternography (72.3 %). The sensitivity of CT cisternography at detecting CSF fistulae in patients with a size of dural lesion less than 2 mm or in patients with multiple dural lesions is significantly lower compared with the MR method. Although the localization of CSF fistulae always proved possible with MR cisternography, this could only be accomplished wih CT in 70 % of cases. The MR cisternography technique is a new examination method with a higher sensitivity for the detection of CSF fistulae than CT cisternography. The CISS technique is superior compared with PSIF and should be used in patients with high-flow CSF fistulas.


Subject(s)
Central Nervous System Diseases/diagnosis , Cerebrospinal Fluid , Dura Mater , Fistula/diagnosis , Magnetic Resonance Imaging/methods , Adolescent , Adult , Central Nervous System Diseases/diagnostic imaging , Cerebrospinal Fluid Rhinorrhea/diagnosis , Cerebrospinal Fluid Rhinorrhea/diagnostic imaging , Dura Mater/diagnostic imaging , Dura Mater/injuries , Dura Mater/pathology , Female , Fistula/diagnostic imaging , Humans , Male , Middle Aged , Prospective Studies , Sensitivity and Specificity , Subarachnoid Space/diagnostic imaging , Subarachnoid Space/pathology , Tomography, X-Ray Computed
8.
Rofo ; 167(6): 605-11, 1997 Dec.
Article in German | MEDLINE | ID: mdl-9465956

ABSTRACT

PURPOSE: We compared a new MR method for diagnosis of CSF fistulas with CT cisternography. MATERIAL AND METHODS: In a prospective case study we examined 35 patients with posttraumatic CSF fistulas and compared the results with the intraoperative findings. The MR investigation was performed using a 1.0T whole body MR-system. We used a strongly T2*-weighted 3D-CISS sequence. The examinations were performed in prone position, in patients with severe CSF rhinorrhoea additionally in supine position. RESULTS: The sensitivity and specificity of the MR method (88.9% and 95.1%) is higher compared with CT cisternography (77.8% and 87.8%). The reason for the lower sensitivity of CT compared with MRI are complex fracture systems, involving several paranasal cavities in patients with false positive results in CT cisternography. Reasons for the lower specificity of CT cisternography are false negative results in patients with small dural lesions below 2 mm2. CONCLUSION: Using a new method MRI can detect CSF-fistulas. The MR method is superior to CT cisternography, is noninvasive, the administration of contrast and agent is no longer necessary.


Subject(s)
Cerebrospinal Fluid Rhinorrhea/diagnosis , Fistula/diagnosis , Magnetic Resonance Imaging/methods , Adolescent , Adult , Cerebrospinal Fluid Rhinorrhea/diagnostic imaging , Cisterna Magna/diagnostic imaging , Dura Mater/diagnostic imaging , Dura Mater/injuries , Ethmoid Bone/diagnostic imaging , Ethmoid Bone/injuries , Evaluation Studies as Topic , Female , Fistula/diagnostic imaging , Humans , Male , Middle Aged , Prospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed
9.
Aktuelle Radiol ; 6(6): 344-7, 1996 Nov.
Article in German | MEDLINE | ID: mdl-9081410

ABSTRACT

PURPOSE: To determine the reliability and the measuring agreement between two radiologists in the identification of relevant structures of prostate anatomy in patients with prostate carcinoma. PATIENTS AND METHOD: 15 patients with prostate carcinoma proved by histology underwent MR Imaging on 1.5 Tesla MR-system (Siemens Erlangen). T1- and T2-weighted sequences were used in the depiction of important anatomic structures for diagnosing prostate cancer. 5 sequences of every patient were evaluated for 5 times by each reader. Reliability was proved by the intraclass correlation coefficient and the measuring agreement was proved by Cohen's cappa test. RESULTS: Only the T2-weighted sequence was of sufficient sensitivity to reach a moderate reliability (r1 = 0.74) and a moderate measurement agreement between the two readers (kappa = 0.5). CONCLUSION: For the evaluation of MR images in staging prostate carcinoma, besides the validity and the measuring agreement, the reliability of the radiologist is the important factor.


Subject(s)
Magnetic Resonance Imaging/statistics & numerical data , Prostatic Neoplasms/diagnosis , Analysis of Variance , Humans , Male , Observer Variation , Prostate/pathology , Prostatic Neoplasms/pathology
10.
MAGMA ; 3(2): 77-81, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7496889

ABSTRACT

An anatomical study was carried out to determine the extent to which magnetic resonance imaging (MRI) could delineate inner ear structures. Anatomical preparations of human petrous temporal bone were examined and compared with the results of MRI in 20 healthy subjects to see whether the structures of the inner ear could be visualized. Imaging of the subjects was carried out in a 1.0-T MRI scanner (Siemens Magnetom Impact). Two strongly T2*-weighted sequences were used: a 3D-PSIF sequence and a 3D-CISS sequence. The 3D data sets were postprocessed using a Maximum Intensity Projection (MIP) program. Our investigations show that it is possible to obtain accurate visualization of structures with a diameter of under 1 mm. In all 20 subjects it was possible to identify both the endolymphatic duct and the endolymphatic sac.


Subject(s)
Endolymphatic Duct/anatomy & histology , Endolymphatic Sac/anatomy & histology , Adult , Female , Humans , Magnetic Resonance Imaging/methods , Male
11.
Aktuelle Radiol ; 4(6): 313-7, 1994 Nov.
Article in German | MEDLINE | ID: mdl-7819293

ABSTRACT

65 patients with nerve root compression syndrome were examined using a new type of MR-technique, which is comparable to the conventional X-ray myelography. The results of the prospective case study were compared with previous clinical experiences (1). For the examinations a 1.0T whole body MR-system (Siemens Magnetom Impact) was used. A strong T2*-weighted 3D-FISP sequence (TR = 73 ms, TE = 21 ms, alpha = 7 degrees) was applied in sagittal orientation using a circularly polarized oval spine coil. To obtain fat suppression a frequency selective 1-3-3-1 prepulse was applied prior to the imaging sequence. The acquired 3D-data set was evaluated using a Maximum Intensity Projection (MIP) program. Our results confirmed earlier experiences which showed that the diagnostic sensitivity of 3D-MR myelography (3D-MRM) is comparable to that of conventional X-ray myelography. In cases of severe spinal canal stenosis and spondylolisthesises, and in cases of postoperative scar tissue with nerve root compressions, the sensitivity of the 3D-MRM is higher as compared to that of conventional X-ray myelography.


Subject(s)
Image Processing, Computer-Assisted/instrumentation , Magnetic Resonance Imaging/instrumentation , Myelography/instrumentation , Nerve Compression Syndromes/diagnosis , Spinal Nerve Roots , Adult , Aged , Aged, 80 and over , Cicatrix/diagnosis , Female , Humans , Intervertebral Disc Displacement/diagnosis , Intervertebral Disc Displacement/surgery , Lumbar Vertebrae/pathology , Lumbar Vertebrae/surgery , Male , Middle Aged , Nerve Compression Syndromes/surgery , Neurilemmoma/diagnosis , Neurilemmoma/surgery , Peripheral Nervous System Neoplasms/diagnosis , Peripheral Nervous System Neoplasms/surgery , Postoperative Complications/diagnosis , Prospective Studies , Spinal Nerve Roots/pathology , Spinal Nerve Roots/surgery , Spinal Stenosis/diagnosis , Spinal Stenosis/surgery , Spondylolisthesis/diagnosis , Spondylolisthesis/surgery
14.
Rofo ; 160(1): 59-65, 1994 Jan.
Article in German | MEDLINE | ID: mdl-8305694

ABSTRACT

MR studies using turbo spin-echo pulse sequences (TSE) were performed on 27 patients with histologically confirmed prostate cancer. A prospective study was conducted in 15 patients who underwent radical prostatectomy. Turbo SE pulse sequences generate strongly T2-weighted images of excellent quality with reduction of measurement time by a factor of 4-6. A comparison with standard T2-weighted spin-echo pulse sequences indicated an objective improvement in the contrast of pathological structures (p < 0.001). With respect to differentiation of stages T2 and T3 (TNM) during pathohistological correlation, sensitivity of 80%, specificity of 40% and an accuracy rate of 67% were obtained. Sensitivity of 71% and specificity of 75% were obtained when decoding cases of infiltration into the seminal vesicles, with an accuracy rate of 73%.


Subject(s)
Adipose Tissue/pathology , Magnetic Resonance Imaging/methods , Prostate/pathology , Prostatic Neoplasms/pathology , Aged , Evaluation Studies as Topic , False Negative Reactions , False Positive Reactions , Humans , Lymphatic Metastasis , Magnetic Resonance Imaging/instrumentation , Magnetic Resonance Imaging/statistics & numerical data , Male , Middle Aged , Neoplasm Recurrence, Local/epidemiology , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Prospective Studies , Prostatic Neoplasms/epidemiology , Seminal Vesicles/pathology , Sensitivity and Specificity
16.
J Magn Reson Imaging ; 2(6): 731-4, 1992.
Article in English | MEDLINE | ID: mdl-1446119

ABSTRACT

A strongly T2*-weighted, three-dimensional (3D) PSIF (time-reversed FISP [fast imaging with steady-state precession]) gradient-echo magnetic resonance (MR) sequence, with postprocessing of the 3D data set with a maximum-intensity projection (MIP) algorithm, produced x-ray myelography-equivalent images. The method was tested in 10 healthy volunteers to optimize sequence parameters and was evaluated in 30 patients with proven lumbar disk disease. MIP myelograms, unlike two-dimensional MR images, could not show the pathologic disks themselves but clearly demonstrated the effect on the thecal sac, giving a clear overall view of its geometry and dimensions, especially when displayed in a cine loop. All 28 medial and mediolateral disk herniations could be visualized, whereas only three of eight intraforminal disk herniations were seen on MR myelograms.


Subject(s)
Image Processing, Computer-Assisted , Intervertebral Disc Displacement/diagnosis , Magnetic Resonance Imaging/methods , Spinal Cord/anatomy & histology , Adult , Female , Humans , Male , Middle Aged
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