Calcineurin-inhibitor induced pain syndrome (CIPS): a severe disabling complication after organ transplantation.

Bone pain after transplantation is a frequent complication that can be caused by several diseases. Treatment strategies depend on the correct diagnosis of the pain. Nine patients with severe pain in their feet, which was registered after transplantation, were investigated. Bone scans showed an increased tracer uptake of the foot bones. Magnetic resonance imaging demonstrated bone marrow oedema in the painful bones. Pain was not explained by other diseases causing foot pain, like reflex sympathetic dystrophy, polyneuropathy, Morton's neuralgia, gout, osteoporosis, avascular necrosis, intermittent claudication, orthopaedic foot deformities, stress fractures, and hyperparathyroidism. The reduction of cyclosporine- or tacrolimus trough levels and the administration of calcium channel blockers led to relief of pain. The Calcineurin-inhibitor Induced Pain Syndrome (CIPS) is a rare but severe side effect of cyclosporine or tacrolimus and is accurately diagnosed by its typical presentation, magnetic resonance imaging and bone scans. Incorrect diagnosis of the syndrome will lead to a significant reduction of life quality in patients suffering from CIPS.

Ultrasound demonstration of mammographically detected microcalcifications.

PURPOSE: To evaluate the capabilities of breast ultrasound (US) for identifying microcalcifications in benign breast changes, in situ carcinomas, and small nonpalpable invasive carcinomas. MATERIAL AND METHODS: Forty-six consecutive patients with 49 clustered microcalcifications detected by mammography were included in this prospective study. Patients with palpable breast lesions were excluded. Breast US was performed with knowledge of mammographic findings for presence and visibility of microcalcifications, and for parenchymal structure abnormalities. Mammographic and US findings were compared with histology. RESULTS: Nine ductal in situ carcinomas, 2 lobular in situ carcinomas, 11 invasive carcinomas and 27 benign lesions were confirmed by histology. For all lesions, US achieved a sensitivity of 75% in the detection of microcalcifications. The detection rate for microcalcification in invasive and in situ carcinomas was 100%. In 11 cases, no microcalcifications were visible on US; they all proved to be benign on histology. CONCLUSION: Microcalcifications in malignant lesions are reliably recognized by US. They are, however, difficult to detect in fibrocystic breast changes.

Comparison of cystourethrography and dynamic MRI in bladder neck descent.

PURPOSE: The purpose of this work was to test whether there are statistically significant differences between dynamic MR and lateral cystourethrogram measurement results in patients with bladder neck descent. METHOD: Twenty-seven women (39-83 years old, mean 60.6 years old) with urinary incontinence and bladder neck descent were examined by dynamic MRI using a single shot fast spin echo sequence with half-Fourier data acquisition. Bladder neck position, angle of inclination of the urethral axis, posterior vesicourethral angle, and depth of cystoceles were measured at perineal contraction and at maximal pelvic strain. The nonparametric Wilcoxon test for paired values was used to analyze whether there were statistically significant differences between lateral cystourethrogram and dynamic MR measurement results. The Spearman correlation coefficient (rs) was calculated for all parameter pairs. RESULTS: Measurements at maximal pelvic strain showed the greatest levels of agreement between MRI and cystourethrography. The best results were attained for the cystocele measurements (p > 0.5, rs = 0.95). Bladder neck position showed the second best agreement; if MR measurements were corrected by 0.46 cm, no statistically significant difference (p > 0.2, rs = 0.92) was calculated. Measurements at perineal contraction tallied least, probably due to the different positions adopted during the two examinations. CONCLUSION: Measurement data on dynamic MRI for the bladder neck position and the extension of cystocele at maximal pelvic strain are comparable with lateral cystourethrogram data.

Real-time interactive virtual endoscopy of the tracheo-bronchial system: influence of CT imaging protocols and observer ability.

OBJECTIVE: To evaluate the influence of different spiral CT examination protocols suitable for clinical use on image quality and to assess the observer dependence in interactive real-time virtual bronchoscopy. METHODS AND PATIENTS: Real-time perspective volume rendering of the airways in twenty normal patients based on four different spiral CT examination protocols was evaluated by four observers in regard to the order of depictable bronchi. RESULTS: Best results were obtained using an examination protocol with a small beam collimation and a maximum pitch. Depending on the observer's ability to control the fly path and the orientation of the bronchi with respect to the slice plane up to sixth order bronchi could be depicted. Inter-observer variability was up to two branching orders. CONCLUSION: The performance of virtual bronchoscopy strongly depends on the applied CT examination protocol and the observers experience with perspective volume rendering. Both of which have to be taken into account when virtual bronchoscopy is compared with fiberoptic bronchoscopy.

MRI of heart morphology. Comparison of nongradient echo sequences with single- and multislice acquisition.

RATIONALE AND OBJECTIVES: A large variety of cardiac MRI sequences have been introduced for heart morphology evaluation. The aim of this study was to establish a practicable and robust examination protocol for standard high-field systems applying nongradient echo sequences with single- and multi-slice acquisition. METHODS: Fifty-one patients received electrocardiogramgated MRI of the heart with "black-blood" preparation, comparing three single-slice and three multislice sequences with a T1-weighted turbo spin echo reference sequence. Demarcation of the left ventricular myocardium and cavity and the extent of flow and motion artifacts were assessed. RESULTS: The myocardium and left ventricular cavity were depicted best with the single-slice T1- and T2-weighted turbo spin echo sequence. The nonbreath-hold multislice sequences produced marked artifacts and therefore were of poor diagnostic value. The TIRM haste sequence was best suited for fat suppression. The T2-weighted breath-hold single-shot sequence with half-Fourier imaging proved to be most appropriate for multislice imaging. CONCLUSIONS: Sufficient depiction of heart morphology with comprehensive evaluation of signal changes can be achieved using nongradient spin echo and turbo spin echo sequences with breath-holding. For rational imaging of myocardial and heart chamber morphology, multislice and single-slice sequences should be combined.

Chest wall infiltration by lung cancer: value of thin-sectional CT with different reconstruction algorithms.

The aim of this investigation was to evaluate whether thin-sectional CT with different reconstruction algorithms can improve the diagnostic accuracy with regard to chest wall invasion in patients with peripheral bronchogenic carcinoma. Forty-one patients with intrapulmonary lesions and tumor contact to the thoracic wall as seen on CT staging underwent additional 1-mm CT slices with reconstruction in a high-resolution (HR) and an edge blurring, soft detail (SD) algorithm. Five criteria were applied and validated by histological findings. Using the criteria of the intact fat layer, HRCT had a sensitivity of 81 % and a specificity of 79 %, SD CT had a sensitivity of 96 % and a specificity of 78 %, and standard CT technique had a sensitivity of 50 % and a specificity of 71 %, respectively. Regarding changes of intercostal soft tissue, HRCT achieved a sensitivity of 71 % and a specificity of 96 %, SD CT had a sensitivity of 94 % and a specificity of 96 % (standard CT technique: sensitivity 50 % and specificity 96 %). For the other criteria, such as pleural contact area, angle, and osseous destruction, no significant differences were found. Diagnostic accuracy of chest wall infiltration can be improved by using thin sectional CT. Especially the application of an edge-blurring (SD) algorithm increases sensitivity and specificity without additional costs.

Contrast-enhanced subtraction MR angiography in occlusive disease of the pelvic and lower limb arteries: results of a prospective intraindividual comparative study with digital subtraction angiography in 76 patients.

PURPOSE: The purpose of this work was to evaluate the feasibility and clinical use of MR angiography (MRA) for examining the pelvic and lower limb arteries in patients with arterial occlusive disease. METHOD: Seventy-six patients with clinical signs of peripheral arterial occlusive disease were included in the study. MRA was performed using a fast contrast-enhanced high-resolution 3D technique that covered the area from the distal abdominal aorta to the distal lower limbs in two examination steps. RESULTS: In all patients, diagnostic images comparable with those of conventional intraarterial digital subtraction angiography (DSA) could be obtained. No false-negative findings were seen in the iliac, femoral, or popliteal arteries. Ten to 16% of the mild stenoses and 6-14% of the severe stenoses, mainly in the crural vessels, were overgraded compared with intraarterial DSA. Particularly in patients with proximal severe obstructions or occlusions, the crural segments could be depicted more clearly due to decreased arterial runoff in conventional angiography. CONCLUSION: The consistency of the excellent depiction of the vascular territories of the distal aorta and the pelvic and lower limb arteries in a standardized setting suggests great potential for the use of MRA in the primary diagnosis of peripheral arterial occlusive disease.

Indirect MR arthrography of the unexercised glenohumeral joint in patients with rotator cuff tears.

RATIONALE AND OBJECTIVES: To evaluate the diagnostic utility of indirect MR arthrography of the unexercised glenohumeral joint in patients with rotator cuff tears confirmed by arthroscopy or arthrotomy as the gold standard. METHODS: Twenty-six patients underwent conventional MR imaging and indirect MR arthrography of the stationary glenohumeral joint using a wrap-around surface coil. Unenhanced T1-weighted spin echo/T2-weighted fast spin echo sequences and T1-weighted gradient echo sequences, adding spectral fat suppression after intravenous administration of contrast medium, were performed in the oblique coronal and oblique sagittal planes. Images were analyzed by three experienced radiologists in consensus. Levels of diagnostic confidence were evaluated using a four-point scale of diagnostic certainty. RESULTS: Performing indirect MR arthrography of the unexercised shoulder leads to a diagnostically efficient enhancement of joint fluid (120% at 4 minutes and 145% at 8 minutes after intravenous injection of gadodiamide). In terms of soft tissue delineation, characterization of rotator cuff tears was significantly improved by using enhanced fat-suppressed T1-weighted gradient echo sequences compared with conventional MR imaging. CONCLUSIONS: Indirect MR arthrography without glenohumeral joint exercise in the diagnosis of rotator cuff tears is feasible and represents a more convenient and less time-consuming alternative to indirect MR arthrography after joint exercise.

Comparison between a screen-film system and a selenium radiography system. An ROC study using simulated thoracic lesions.

RATIONALE AND OBJECTIVES: To evaluate the diagnostic image quality of the hard copies of a commercially available selenium detector-based computed radiography system compared to that of a conventional screen-film system. METHODS: Ten radiographs of an anthropomorphic chest phantom with simulated nodular and linear-reticular lesions were produced using either system. Each radiograph was subdivided into 15 fields containing zero lesions, one nodular lesion, one linear-reticular lesion, or both lesions. The total of 150 fields for each modality was reviewed by six radiologists, and receiver operating analysis was performed. RESULTS: The conventional screen-film system performed significantly better for nodular lesions, whereas no statistically significant difference was found between the detection rates of both systems for linear-reticular lesions. CONCLUSIONS: The better detection of nodules with the dedicated selenium detector can be explained by the higher dynamic range of the system. Detection of linear-reticular lesions was slightly but not significantly better with the screen-film system, but the detection rate of the selenium detector might be further improved with a different image processing technique.

[Kinematic versus static MRI study of the cervical spine in patients with rheumatoid arthritis]. / Kinematische versus statische MRT-Untersuchung der Halswirbelsäule bei Patienten mit rheumatoider Arthritis.

PURPOSE: The objective of this study was to compare the diagnostic value of cinematic magnetic resonance imaging with static MRI examinations in patients with rheumatoid arthritis and concomitant attack of the cervical spine. METHODS: Dynamic functional MRI examinations of the cervical spine were performed one five subjects without complaints and 20 patients with rheumatoid arthritis. For the functional studies, a positioning frame was used that allowed infinitely variable forward and backward inclinations of the head. RESULTS: Functional magnetic resonance imaging made possible a sufficiently good differentiation of the extension of pannus tissue cranial, ventral, and dorsal of the dens with possible displacing and impinging effects on the spinal cord during flexing and stretching movements. In addition, it is suitable for demonstration of the degree of instability in the atlanto-occipital and atlanto-axial planes. In contrast to conventional X-rays, CT, and static MRI, basilary impression as well as compressions and angulations of the cervical bone marrow are better visualized by cinematic magnetic resonance tomography. CONCLUSIONS: Functional magnetic resonance tomography is an important diagnostic method for the induction of the cervical spine in patients with rheumatoid arthritis. In particular, fusion and instabilities as well as compressions of the bone marrow often can only be detected with the help of functional MRI.

Comparison of turbo inversion recovery magnitude (TIRM) with T2-weighted turbo spin-echo and T1-weighted spin-echo MR imaging in the early diagnosis of acute osteomyelitis in children.

OBJECTIVE: To compare turbo inversion recovery magnitude (TIRM) with standard T1-weighted (T1-W) and T2-weighted (T2-W) MR sequences in the very early detection of acute osteomyelitis in children. MATERIALS AND METHODS: In 15 children with osteomyelitis, 15 sets of T1-W spin-echo (SE) (TR/TE, 400-640/12-17), T2-W turbo spin-echo (TSE) (TR/TE/ETL, 3290-4465/112-120/11), and TIRM (TR/TE/TI, 4000-6120/60/160) images were acquired with a 1.0-T magnet. Contrast-to-noise (C/N) ratios and percentage of signal between lesion and normal bone marrow were analysed with a computer-assisted image analysing system in a region of interest (ROI). RESULTS: In 13 of 15 patients, the absolute signal enhancement in a ROI on the TIRM images was better than on the T1-W SE and T2-W TSE images and in 14 of 15 cases, C/N ratios were also better on the TIRM images than on the other sequences. In the other cases, the TIRM signal was diagnostically equivalent. On the TIRM images, the signal difference between normal and pathological tissue was increased to 43-281% (mean 124%). On the T2-W TSE images, this signal difference was 4-79% (mean 36%) and on the T1-W SE images 6-77% (mean 37%). Conclusion. The TIRM sequence is highly sensitive for detecting bone marrow oedema in the very early stage of acute osteomyelitis in children. MRI utilising the TIRM sequence allowed for an early diagnosis. With scan time of less than 4 minutes, this sequence is superior to T1-W SE and T2-W TSE images for detecting early osteomyelitis-associated bone marrow oedema.

Functional MR imaging of the cervical spine in patients with rheumatoid arthritis.

PURPOSE: To evaluate functional MR imaging in patients with rheumatoid arthritis (RA) involving the cervical spine. MATERIAL AND METHODS: We used a device that allows MR examination to be made of the cervical spine in infinitely variable degrees of flexion and extension. Dynamic functional MR imaging was performed on 25 patients with RA. RESULTS: Functional MR imaging was able to show the degree of vertebral instability of the occipito-atlantal or atlanto-axial level as well as the subaxial level. By performing functional MR imaging, we were able to demonstrate the extent of synovial tissue around the dens, and the impingement and displacement of the spinal cord during flexion and extension. The basilar impression, the cord impingement into the foramen magnum, the cord compression, the slipping of vertebrae, and the angulation of the cord were all much more evident in functional than in static MR imaging. CONCLUSION: Functional MR imaging provided additional information in patients with RA, and is valuable in patients who have a normal MR study in the neutral position and yet have signs of a neurological deficit. Functional MR imaging is important in the planning of stabilizing operations of the cervical spine.

Human articular cartilage: in vitro correlation of MRI and histologic findings.

The aim of our study was to correlate MRI with histologic findings in normal and degenerative cartilage. Twenty-two human knees derived from patients undergoing amputation were examined with 1.0- and 1. 5-T MR imaging units. Firstly, we optimized two fat-suppressed 3D gradient-echo sequences. In this pilot study two knees were examined with fast imaging with steady precession (FISP) sequences and fast low-angle shot (FLASH, SPGR) sequence by varying the flip angles (40, 60, 90 degrees) and combining each flip angle with different echo time (7, 10 or 11, 20 ms). We chose the sequences with the best visual contrast between the cartilage layers and the best measured contrast-to-noise ratio between cartilage and bone marrow. Therefore, we used a 3D FLASH fat-saturated sequence (TR/TE/flip angle = 50/11 ms/40 degrees) and a 3D FISP fat-saturated sequence (TR/TE/flip angle = 40/10 ms/40 degrees) for cartilage imaging in 22 human knees. The images were obtained at various angles of the patellar cartilage in relation to the main magnetic field (0, 55, 90 degrees). The MR appearances were classified into five categories: normal, intracartilaginous signal changes, diffuse thinning (cartilage thickness < 3 mm), superficial erosions, and cartilage ulcers. After imaging, the knees were examined macroscopically and photographed. In addition, we performed histologic studies using light microscopy with several different stainings, polarization, and dark field microscopy as well as electron microscopy. The structural characteristics with the cartilage lesions were correlated with the MR findings. We identified a hyperintense superficial zone in the MR image which did not correlate to the histologically identifiable superficial zone. The second lamina was hypointense on MRI and correlated to the bulk of the radial zone. The third (or deep) cartilage lamina in the MR image seemed to represent the combination of the lowest portion of the radial zone and the calcified cartilage. The width of the hypointense second zone correlated weakly to the accumulation of proteoglycans in the radial zone. The trilaminar MRI appearance of the cartilage was only visible when the cartilage was thicker than 2 mm. In cartilage degeneration, we found either a diffuse thinning of all layers or circumscribed lesions ("cartilage ulcer") of these cartilage layers in the MR images. Early cartilage degeneration was indicated by a signal loss in the superficial zone, correlating to the histologically proven damage of proteoglycans in the transitional and radial zone along with destruction of the superficial zone. We found a strong effect of cartilage rotation in the main magnetic field, too. A rotation of the cartilage structures caused considerable variation in the signal intensity of the second lamina. Cartilage segments in a 55 degreesangle to the magnetic main field had a homogeneous appearance, not a trilaminar appearance. The signal behavior of hyaline articular cartilage does not reflect the laminar histologic structure. Osteoarthrosis and cartilage degeneration are visible on MR images as intracartilaginous signal changes, superficial erosions, diffuse cartilage thinning, and cartilage ulceration.

Magnetic resonance diagnosis of the anterior labrum and capsule. Effect of field strength on efficacy.

RATIONALE AND OBJECTIVES: The authors compare the performance of high-field and low-field magnetic resonance (MR) systems in the evaluation of shoulder instability, 35 patients were examined at field strengths of 1.0 T and of 0.2 T. METHODS: Surface coils were used in both systems. Because arthroscopy was used as gold standard, a preselected patient-population was obtained for the study. RESULTS: The sensitivity/specificity/accuracy of MR images acquired at 1.0 T for labrum pathology were 91%/67%/91% and 70%/80%/71% for the capsular complex. Compared with the above, the sensitivity/specificity/accuracy for 0.2 T MR images revealed 91%/67%/91% for the labrum pathology and 63%/80%/66% for the capsular complex respectively. In the evaluation of capsular lesions a comparison between the 0.2 T MR system and the 1.0 T system indicated a higher sensitivity and accuracy for the high-field images. Concerning labral lesions, the sensitivity and accuracy of the 0.2 T MR imager and the 1.0 T imager were comparable. CONCLUSIONS: Given differences in imaging protocols, imaging at 0.2 T does not adversely affect the assessment of shoulder instability when compared with imaging at 1.0 T. These preliminary results warrant more extensive clinical comparison of results obtained at different magnetic field strengths.

Comparison of MR sequences in quantifying in vitro cartilage degeneration in osteoarthritis of the knee.

Magnetic resonance imaging of amputated human knees was performed to determine optimal sequences for depicting articular cartilage. 24 knees were examined with eight different sequences in a 1.0 T imager. Each cartilage lesion was graded from 1 to 4 (Outerbridge staging system). The results of each sequence were compared with the macroscopic findings and statistically tested against each other. The FLASH sequence (TR = 50 ms) with combination of flip angle of 40 degrees and echo time of 10 ms and the FISP sequence (TR = 40 ms) with combination of flip angle of 40 degrees and echo time of 11 ms were best for depicting cartilage structure and internal detail. There was no significant difference between fat-saturated three-dimensional FLASH (FS-3D-FLASH) and FS-3D-FISP (p = 0.05). These FS-3D sequences were significantly better than sequences without fat saturation (p = 0.05). There was no significant difference between magnetization transfer (MT) 3D-FLASH, MT-3D-FISP and 3D-FISP. All 3D sequences showed significantly (p = 0.05) better results than spin echo or fast spin echo sequences. The T1 weighted SE pulse sequence was significantly (p = 0.005) better than the T2 weighted TSE sequence. Fast T2 weighted spin echo was not suitable for early and accurate detection of cartilage lesions.

A mild form of Proteus syndrome.

Proteus syndrome is a rare congenital hamartomatous syndrome. We report on the clinical and radiological appearances of a boy in order to illustrate the typical signs which include subcutaneous masses, in mild forms partial gigantism of hands and feet, hemihypertrophy, and bony abnormalities. We discuss how to make the definitive diagnosis on the basis of using a known rating scale, important aspects of differential diagnosis and clinical features, and diagnostic management.

[Recent developments and applications of MRI sequence technique. I: turbo spin echo, HASTE, turbo inversion recovery, turbo gradient echo, turbo gradient spin sequences]. / Neuere Entwicklungen und Anwendungen in der MR-Sequenztechnik. Teil I: Turbo-Spin-Echo, HASTE, Turbo-Inversion-Recovery, Turbo-Gradienten-Echo, Turbo-Gradienten-Spin-Echo-Sequenzen.

Goal of this two-part report is to provide clinical MRI radiologists with a guide to the world of new and clinically available MRI pulse sequences. Discussed are the principles of rapid scan techniques like multiple spin-echo imaging, multiple gradient echo imaging, echo planar imaging, diffusion and perfusion imaging, and future perspectives (review article).

Cartilage destruction in small joints by rheumatoid arthritis: assessment of fat-suppressed three-dimensional gradient-echo MR pulse sequences in vitro.

PURPOSE: To assess the accuracy of different MR sequences for the detection of articular cartilage abnormalities in rheumatoid arthritis. DESIGN AND PATIENTS: Ten metacarpophalangeal joints and 10 metatarsophalangeal joints (specimens from arthritis patients undergoing ablative joint surgery) were examined with a fat-suppressed (FS) 3D FLASH, a FS 3D FISP, a FS 2D fast spin-echo T2-weighted, and a 2D FS spin-echo T1-weighted sequence. Each cartilage lesion and each cortical lesion was graded from 0 to 4 (modified Outerbridge staging system). Subsequently, the results of each sequence were compared with the macroscopic findings and statistically tested against each other. RESULTS: The study shows that 3D gradient-echo sequences with fat suppression were best for imaging and grading of cartilage lesions in arthritis of the small joints of the hands and feet. Using 3D techniques, all grade 2, grade 3, and grade 4 lesions of cartilage or cortical bone were detected. CONCLUSION: FS 3D gradient-echo techniques were best for the detection and grading of hyaline cartilage and subchondral bone lesions in rheumatoid arthritis. MRI has a great potential as an objective method of evaluating cartilage damage and bone erosions in rheumatoid arthritis.