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M Breitenseher

Publications and source records attributed to M Breitenseher.

At least 55 records · Page 3Linked to original sources
PubMed1997

Imaging of avascular necrosis of bone.

The etiology of avascular necrosis (AVN) is multifactorial. Independent of its etiology and localization it shows typical pathologies and radiological images. In the early stages localized subchondral edema is characteristic. In 50 % of all cases accompanying joint effusion may be found. Due to necrosis of the cells of bone marrow and bone fibrovascular, reactions with hyperemia can be delineated. These reactions allow us to visualize necrosis indirectly. The best imaging methods are MRI and, to a lesser extent, bone scintigraphy. In later stages calcification as well as new bone formation and microfractures are typically demonstrated and visualized best with plain X-rays and CT. Why reparations in many cases, particularly in the hip, are incomplete and may stop in any stage is unknown. Over years clinically complete silent AVNs are not an uncommon finding. Prognosis depends on the localization and size of the AVN. The number of repair mechanisms is best outlined with contrast-enhanced MRI and return of fatty marrow.

Bone and Bones↗
PubMed1997

Reduction of adverse events in MRI of the breast by personal patient care.

PURPOSE: To determine the difference in anxiety reactions in patients undergoing standard (non-breast) magnetic resonance imaging (MRI) compared to breast magnetic resonance imaging (MRM) and to evaluate the influence of patient information before the breast imaging examination on the rate of premature termination of the procedure. MATERIALS AND METHODS: Over 2 years, 5837 non-breast and 336 breast magnetic resonance examinations were performed at our institution. One group of breast MRM patients (n = 144) received detailed information and a second group (n = 189) received only routine information before MRI. The rates of premature termination were recorded for all groups. RESULTS: In 0.5% (27/5837) of patients undergoing standard MRI examinations the study had to be stopped prematurely. Of the breast MRM patients, those who had received only routine information had a significantly higher rate of premature termination when compared to the better-informed patients and those undergoing standard MRI (5.5%, 10/189, P= 0.01). A significantly lower rate of premature termination occurred in the better-informed breast group (0%, 0/144). CONCLUSION: MRM is associated with an increase in patient anxiety and higher rates of incomplete examination than other MR procedures. We recommend careful patient preparation including detailed verbal information before MRM and support during the procedure to obtain optimal patient compliance.

Anxiety↗
PubMed1997

Sonomorphology of the gallbladder in critically ill patients. Value of a scoring system and follow-up examinations.

PURPOSE: The aim of the study was to assess the value of a scoring system for the diagnosis of acalculous cholecystitis (AC) on ultrasound (US) follow-up examinations and to discuss the merits of scoring system compared to clinical outcome and pathohistologic findings. MATERIAL AND METHODS: In this prospective study, 21 patients at the intensive care unit (ICU) of a medical department were examined by follow-up US. Sonographic parameters of the gallbladder (GB) were obtained (longitudinal and transversal diameter, wall thickening, contents, and pericholecystic fluid) and scored (2 points: distension of GB, thickening of GB wall; 1 point: striated thickening of GB wall, sludge, and pericholecystic fluid; range (0-8). The US findings were correlated with clinical findings and histology at cholecystectomy or autopsy. RESULTS: Of a total of 77 follow-up examinations in these 21 patients, US demonstrated GB distension in 19 patients, wall thickening in 18, sludge in 15, striated thickening of the GB wall in 13, and pericholecystic fluid in 12 patients. Of these, 41 (53%) examinations were scored > or = 6, and 36 (47%) examinations < or = 5. None of the patients with a maximum score during follow-up of < or = 5 (n = 8) had pathohistologic proof of AC or died due to GB complications. Patients with maximum scores of > or = 6: had pathohistologic proof of AC (n = 4); survived with normalization of GB morphology (n = 4); had a normal GB at autopsy (n = 1); or were lost for pathohistologic proof at autopsy (n = 2). CONCLUSION: Our results indicate that regular, short-term follow-up allows early diagnosis and immediate therapy for AC. The scoring system could be helpful in differentiating between patients with an abnormal GB without AC (score < or = 5) and those with an abnormal GB (score > or = 6) with a suspicion of AC. In the latter group, more aggressive diagnostic and therapeutic procedures may be indicated.

Adolescent↗
PubMed1997

MR-guided joint puncture and real-time MR-assisted contrast media application.

OBJECTIVE: To develop, in MR arthrography of the shoulder joint, an MR-guided technique for localizing the needle puncture and confirming the intracapsular needle-tip position by visualization of the contrast media inflow. MATERIAL AND METHODS: Three unfixed human shoulder specimens were examined on a 1.0 T MR unit. On the basis of MR-compatible markers, the optimal entrance point for puncturing the joint was determined. The precise localization of the needle tip (MR-compatible 0.7-mm needle) in the shoulder joint was determined with rapid localizer GRE sequences in 2 orthogonal planes. To confirm the intracapsular position of the needle tip, diluted Gd-DTPA was applied via a long connecting tube and contrast medium inflow into the joint space was controlled on an LCD screen in real-time MR imaging (local-look technique). RESULTS: MR-compatible markers on the skin allowed the rapid determination of the optimal entrance point for needle puncture. An adequate localization of the intra-articular needle-tip position was possible in all specimens although significant artifacts were present on rapid localizer GRE sequences which resulted in an increase in the apparent width of the needle shaft. Real-time MR imaging of the contrast medium inflow was made possible by the local-look technique and LCD screen on the MR unit and this allowed confirmation of the intracapsular position. CONCLUSION: In MR arthrography of the shoulder, an MR-guided technique in conjunction with the LCD screen and real-time MR imaging would seem to be a practical alternative to conventional fluoroscopic guidance.

Artifacts↗
PubMed1997

GRASE: ultra-fast turbo gradient spin-echo sequence. A new approach to fast MR imaging of the musculoskeletal system.

PURPOSE: Ultra-fast gradient and spin-echo (GRASE) imaging is a hybrid of turbo spin-echo (TSE) and echo-planar imaging (EPI). One scan consists of several spin echoes (SEs) (turbo factor, TF), each of which consists of a number of gradient echoes (EPI factor, EF). The aim of our study was to evaluate different combinations of TF and EF in GRASE imaging and to test its usefulness in musculoskeletal imaging. MATERIAL AND METHODS: On a 1.0 T MR unit, 11 GRASE sequences with different combinations of TF and EF (TR/TE 2150/120 ms) were evaluated in phantom studies with respect to signal-to-noise (S/N) ratio, nonuniformity of images, and geometrical distortion. From this study, the optimal GRASE-sequence was applied to 25 patients with different joint pathologies and compared to a T2-weighted TSE sequence (TR/TE 2855/130 ms). Lesion visualization, conspicuity, overall image quality, and artifacts were qualitatively analyzed by two observers independently of each other. RESULTS: With respect to S/N ratio, signal nonuniformity, and geometrical distortion, the GRASE sequence with TF/EF 7/3 (S/N 47; signal nonuniformity 11.7%; distortion 1 pixel) proved to be superior to the other GRASE sequences within a scanning time of less than 120 s. In a clinical study, the GRASE sequence proved superior to T2-weighted TSE (without fat suppression) in the visualization of bone-marrow and soft-tissue lesions (p < 0.001) and ligamentous injuries, although the image quality was inferior.

Artifacts↗
PubMed1997

Diagnostic patterns for bone marrow oedema syndrome and avascular necrosis of the femoral head in dynamic bone scintigraphy.

This study used logistic regression analysis to assess qualitative patterns of tracer accumulation in an attempt to improve the diagnostic utility of bone scintigraphy for the detection of the bone marrow oedema syndrome (BMOS) and avascular necrosis (AVN) of the femoral head. Forty-eight symptomatic patients aged 44 +/- 9 years (mean +/- S.D.) with a final diagnosis of AVN (n = 29 hips), BMOS (n = 22), nine other hip disorders or a normal hip were examined with dynamic bone scintigraphy and qualitatively assessed for 11 scintigraphic signs in four phases by three blinded investigators. The accuracy for a correct diagnosis based on individual experience was 60-61% for the three observers, even if different signs were emphasized. A cold spot in the femoral head in both blood pool phases and the bone phase was seen only in 24% of AVN hips. Diffuse tracer accumulation in the femoral head, neck and the intertrochanteric region in the blood pool phases was seen only in 36% of BMOS hips. The arterial phase and the finding of a normal acetabulum in the bone phase had no diagnostic utility in this study. The presence of uptake increased the accuracy of differentiating AVN and BMOS from other disorders or normal hips to 88%. AVN could be differentiated from BMOS with an accuracy of 86% if the signs of the femoral head and inter-trochanteric uptake were combined into a diagnostic pattern. The scintigraphic pattern described increases the diagnostic accuracy of planar dynamic bone scintigraphy for BMOS and AVN.

Adult↗
PubMed1996

[Differential diagnosis of diseases of the Achilles tendon. A clinico-sonographic concept].

Ultrasound of the Achilles tendon is a suitable means of differentiating various diseases of the tendon and the surrounding tissue. Different forms of degenerative disease (tendinitis, peritendinitis or bursitis, fibroosteitis, and Haglund's disease) can be discriminated from rheumatic and metabolic diseases. Congenital and developmental abnormalities can also be detected. Tendon degeneration mainly occurs in the ventral part of the medial third of the tendon ("critical zone"). Immature tissue in this area leads to temporary [correction of temorary] instability of the tendon with a high risk of rupture ("vulnerable phase"). With sonography, lesions of the Achilles tendon are visible early in the course of the disease.

Achilles Tendon↗
PubMed1996

[CT and MRI of small intestine interposition after oropharyngeal tumor resection].

Freely transplanted, microvascularly anastomosed jejunal patches can be used to cover soft tissue defects in the oral cavity or oropharynx after the resection of malignant tumors. Even a patch without complications or alteration from tumor recurrence is morphologically diverse. Therefore it is difficult to distinguish between malignant and benign alterations, and knowledge of the possible morphological spectrum and the significance of an alteration is of practical interest. Computed tomography (CT; n = 30) and magnetic resonance imaging (MRI; n = 13) were used for follow-up examinations in patients who had an operative reconstruction with a jejunal patch. Three parts of a patch were differentiated with both imaging modalities: the region of the anastomosis, the mesenterial fatty tissue and the intestinal wall. The morphology of the patches correlated with clinical findings in the following cases. The patches were identified satisfactorily by CT and MRI. The appearance of patches without complications was influenced by a variable degree of fibrosis and by persistent intestinal folds. Recurrent tumors only infiltrated the margins of the patches. Destructive alterations in the patches were always less severe than those in the original orofacial soft tissue. Postoperative follow-up examinations with CT and MRI are particularly important when tumor recurrences spread under a patch, since these tumors are invisible in the clinical examinations. CT was advantageous in demonstrating osseous alterations and showed less loss of image quality in patients for whom the implantation of multiple metallic hardware during the operation had been necessary.

Adult↗
PubMed1996

[Primary chronic polyarthritis of the knee joint].

Rheumatoid arthritis is a chronic, multisystemic disease. The characteristic feature is persistent inflammatory synovitis. The knee joint is commonly involved with synovial hypertrophy, chronic effusion, and frequently ligamentous laxity. Pain and swelling behind the knee may be caused by extension of inflamed synovium into the popliteal space (Baker's cyst). Plain radiographs of the knee joint remain the basic radiological procedure, although early in the disease they might not provide significant changes. Sonography sufficiently reveals synovial fluid and Baker cysts, but cannot be recommended for evaluation of synovial proliferations or pannus formation. Computer tomography has only limited indications and may be used for the evaluation of subtle erosive lesions or the quantitation of osteoporotic changes. Magnetic resonance imaging has shown excellent visualization of cartilage, fluid, synovium and soft tissues and is the method of choice for the demonstration of early affection and the evaluation of pannus activity and therapy control. With administration of contrast agents (gadolinium), dynamic studies may demonstrate inflammatory activity. Modern MR sequences, such as T1 SE "fat sat" or magnetization transfer, further improve the discrimination of cartilage, pannus and synovial fluid.

Arthritis, Rheumatoid↗
PubMed1996

[MRI-guided MRI arthrography of the shoulder].

PURPOSE: To develop an MR-guided technique for joint puncture in MR arthrography of the shoulder and to confirm the intracapsular position of the needle tip by visualization of the flow of contrast media into the joint. MATERIALS AND METHODS: Three unfixed human shoulder joint specimens were examined on a LOT unit. The optimal point of entrance and depth for joint puncture were estimated by means of MR-compatible markers on the skin. Needle orientation and localization of the needle tip (MR-compatible 22-gauge needle) in the shoulder joint were monitored by rapid localizer gradient-echo sequences in two or thogonal planes. To confirm the intracapsular position of the needle tip, diluted gadolinium-DTPA was administered via a long connecting tube and the flow of contrast media into the joint was viewed directly on an LCD screen using real-time MR imaging (local look technique). RESULTS: The MR-compatible markers on the skin allowed determination of the optimal point of entrance and estimation of the depth for joint puncture. Passive visualization of the MR-compatible needle due to spin dephasing and signal loss provided adequate localization of the intra-articular needle tip position in all specimens, although significant artefacts were present on rapid localizer gradient-echo sequences with an increase in width of the apparent needle shaft. Real-time MR imaging of the flow of contrast media was possible using the local look technique and the LCD screen of the MR unit and allowed confirmation of the intracapsular position. CONCLUSION: MR-guided joint puncture and real-time MR-assisted contrast media application results in improved MR-arthrography and may replace conventional fluoroscopic guidance.

Contrast Media↗
PubMed1996

[Diagnostic imaging in osteomyelitis. Characteristics in childhood].

The prognosis of acute hematogenous osteomyelitis in children is mainly influenced by early diagnosis and prompt initiation of antibiotic and surgical therapy. In this age group, two forms of manifestation are differentiated: osteomyelitis in infants up to 18 months and juvenile osteomyelitis until the closure of the epiphyseal plate. Osteomyelitis in infants is often accompanied by septic arthritis of the adjacent joint. In juvenile osteomyelitis, the disease is mostly confined to the metaphysis. Plain films and ultrasonography represent the basic imaging modalities. Depending on the age of the child, the clinical course of the disease and the availability of the various methods, MRI and multiphase bone scintigraphy can be performed for further imaging. CT is of only limited value and should only be used for special cases concerning chronic osteomyelitis.

Acute Disease↗
PubMed1996

[MR arthrography of the shoulder joint in a postoperative patient sample].

Indications of MR arthrography were analyzed in this prospective study. The aim was to evaluate possible advantages over conventional MRI, establish diagnostic criteria and to analyze its meaning further for the therapeutic management of postoperative patients. MR arthrography was performed in eight patients who had undergone surgical repair of rotator cuff lesions (modified Neer acromioplasty) and in six patients who had undergone arthroscopic therapy of recurrent unidirectional dislocation of the shoulder by combined arthroscopic intra- and extracapsular repair. MR investigations were performed before and after application of a contrast solution (2 mmol Gd-DTPA). All patients suffered from chronic postoperative pain. In patients with rotator cuff lesions, a partial tear could be verified in one patient and excluded in all others. In patients after arthroscopic therapy by combined intra- and extracapsular repair, a radiologically patulous-appearing capsule correlated with clinically recurrent dislocations. In all other patients diagnostic criteria, such as distribution of the intra-articular contrast solution, proliferation of scar tissue, nodular appearance of the glenohumeral ligaments and capsule thickness, correlated with a regular postoperative status. MR arthrography of the shoulder represents a promising method in the evaluation of the postoperative shoulder. It might further improve the evaluation of reactive capsule alterations, scar tissue proliferation, and the labroligamentous complex, as well as the ability to differentiate partial and complete rerupture from degenerative changes of the rotator cuff.

Adult↗
PubMed1996

[Ultrasound morphology of the Achilles tendon and differential diagnosis].

AIM: To correlate sonographic findings and clinical disorders of the Achilles tendon, considering newer aspects of their etiology and pathogenesis. METHOD: In a retrospective cross-sectional study the sonographic findings in 52 patients with tendonitis, heel swelling, or suspected rupture were analysed and correlated with the final diagnosis. Tendon lesions due to lipid storage diseases or rheumatic diseases were analysed on the basis of reports in the literature. RESULTS: Ultrasound abnormalities were found in 41 of the 52 symptomatic patients (40 degenerative changes of the tendon and/or the peritendinous tissue, 1 inflammatory rheumatologic process, 1 metabolic disorder, 8 ruptures, 2 congenital or developmental abnormalities). Ultrasound signs were not specific for each of the diagnoses but typical combinations of distinctive signs together with clinical findings led to the correct diagnoses. CONCLUSION: Patients with suspected lesions of the Achilles tendon should undergo an ultrasound investigation both to promote the exact diagnosis and to define the extent of the disease.

Achilles Tendon↗
PubMed1996

Magnetic resonance imaging of occult scaphoid fractures.

Occult fractures of the scaphoid bone occur frequently and may lead to nonunions. In a prospective blind study, we performed magnetic resonance imaging (MRI) examinations on 32 patients who had sustained a wrist injury and in whom a scaphoid fracture was clinically suspected, but could not be confirmed on the original set of two routine and four scaphoid view radiographs. The MRI examinations were performed an average time of 2.8 days after the trauma. This prospective study proved that MRI is able to diagnose occult scaphoid fractures without delay and without the use of radioactive diagnostic means. Sensitivity and specificity of MRI were 100%. This conventional method could save $7,200 (US) per 100,000 inhabitants in providing an immediate and correct diagnosis and avoiding unnecessary cast immobilization. Additional injuries that may be misdiagnosed by conventional radiographs are also detected with a specificity and sensitivity of 100%.

Adolescent↗
PubMed1996

Comparison between conventional and fast spin-echo stir sequences.

PURPOSE: To evaluate the common characteristics and differences in contrast behavior of short-TI-inversion-recovery (STIR) and short-TI-inversion-recovery fast spin-echo (TurboSTIR) sequences. MATERIAL AND METHODS: Phantoms doped with increasing doses of Gd-DTPA and a pork-fat phantom were used to evaluate the dependence of the STIR and TurboSTIR signals on the T1 relaxation time. Clinical TurboSTIR images were obtained from 30 patients with musculoskeletal abnormalities and compared to conventional STIR images in 15 cases and to postcontrast TurboSTIR images in another 15 cases. RESULTS: In the phantom measurements, a significantly shorter inversion time (TI) was needed to achieve fat suppression on TurboSTIR images, and, with an identical number of signal averages, contrast-to-noise ratios were lower on TurboSTIR images. These differences between STIR and TurboSTIR can be attributed to the contribution of stimulated echoes to overall TurboSTIR signal and can be compensated by a shorter TI and a higher number of signal averages for TurboSTIR, respectively. With these adaptations, clinical TurboSTIR and STIR images showed an identical contrast behavior with fat suppression and a high sensitivity to pathological lesions but TurboSTIR saved a significant amount of scan time and reduced some types of artifacts. Contrast uptake impaired lesion conspicuity on TurboSTIR images. CONCLUSION: TurboSTIR sequences should replace conventional STIR sequences and should be performed before contrast administration.

Adolescent↗
PubMed1996

Preoperative imaging of lower extremity varicose veins: color coded duplex sonography or venography.

We prospectively examined 137 limbs in 112 consecutive patients with clinical evidence of severe varicosis by color coded duplex sonography and ascending venography (including varicography in 48 limbs) to evaluate the diagnostic capabilities of color coded duplex sonography in the assessment of venous anatomy, variant varicosis, postthrombotic changes, and incompetence of the superficial and perforating venous system. Additionally, descending venography was performed in the first 52 limbs and compared to color coded duplex sonography in the diagnosis of deep and superficial venous reflux. Variant venous anatomy (21 cases) was missed in two limbs and misinterpreted in one limb by ascending venography compared to surgery. Color coded duplex sonography was inconclusive in two cases. Variant varicosis (59 cases) was missed in seven surgically proved cases by venography and in one case by color coded duplex sonography. Color coded duplex sonography was inconclusive in five cases. Ascending venography was slightly superior to color coded duplex sonography in the detection of postphlebitic changes. Good agreement was found between color coded duplex sonography and descending venography in the grading of superficial (k = 0.75) and deep venous reflux (k = 0.79). Excellent agreement was found between ascending venography in the grading of long (k = 0.96) and short (k = 0.94) saphenous vein reflux. More incompetent perforating veins were detected by ascending venography, (and varicography) than by color coded duplex sonography, but the latter technique allows direct preoperative marking of the skin, which is beneficial for the surgeon. We conclude that color coded duplex sonography is a valuable imaging tool before venous stripping and is capable of replacing invasive ascending and descending venography. Only patients with inconclusive color coded duplex sonographic results (e.g., complex variant venous anatomy) should proceed to venography.

Adult↗