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S Trattnig

Publications and source records attributed to S Trattnig.

At least 55 records · Page 3Linked to original sources
PubMed1999

Cerebral blood flow velocities in an infant with moyamoya disease.

Moyamoya disease is a progressive cerebrovascular disorder with bilateral occlusion of the basal circulation and development of collateral blood supply. In a 6-month-old female with multifocal ischemic infarctions, transcranial pulsed Doppler sonography revealed extremely high and low cerebral blood flow velocities, dampened waveforms, reversed flow, and musical murmurs. Magnetic resonance angiography revealed different degrees of vascular stenosis and an abnormal collateral network. Moyamoya disease was confirmed by conventional angiography at the age of 10.5 months. Pulsed-wave transcranial Doppler sonography is a noninvasive screening method in infants at risk of moyamoya disease.

Blood Flow Velocity↗
PubMed1999

[Occult fractures of the wrist joint: high resolution image magnification roentgen versus MRI].

PURPOSE: To compare the diagnostic value of high definition macroradiography and MRI in patients with the suspicion of occult wrist fractures. MATERIALS AND METHODS: In a prospective study, 23 patients with clinically suspected wrist fractures and normal initial plain radiographs underwent high resolution macroradiography and MR imaging shortly after trauma. Macroradiographs were taken with a microfocus tube using an anode of 0.03-0.3 mm providing a 4x magnification of the wrist, which was obtained in 4 projections. MR images were performed on a 1.0 T MR unit in coronal planes using T1 weighted SE, T2.-weighted 3D GE, and Turbo-STIR sequences. Follow-up radiographs after 6 weeks were used to confirm the diagnosis of a primary occult wrist fracture. RESULTS: Macroradiography depicted 5 wrist fractures: 4 fractures of the scaphoid bone and 1 fracture of the capitate bone. MRI demonstrated 11 fractures (one of them false-positive): 9 fractures of the scaphoid bone and two fractures of the capitate bone. Using macroradiography, the sensitivity for the detection of occult fractures of the wrist was 50% with a specificity of 100%, using MRI the sensitivity was 100% with a specificity of 92%. CONCLUSION: MRI seems to be superior to high resolution macroradiography in the detection of occult scaphoid fractures and thus is recommended in the management of patients with clinically suspected scaphoid fractures not evident on initial plain films.

Adolescent↗
PubMed1999

Importance of subchondral bone to articular cartilage in health and disease.

The almost absolute barrier to diffusion of nutrients between articular cartilage and subchondral bone does not exist. These anatomic regions represent a functional unit. Repetitive overloading in degenerative disease leads primarily to lesions in the subchondral region (including vessels), which in turn impede flow of nutrition to articular cartilage. As a result, in degenerative joint disease the subchondral region shows reactive enhanced vascularization and heightened metabolism with insufficient repair. In aging, however, vascularization and metabolism are decreased; no repair takes place. In many cases, MRI allows visualization of these subchondral abnormalities. It also demonstrates the basic similarities of degenerative osteoarthritis, osteochondritis dissecans, and avascular necrosis. These different entities may have the same basic etiology but with different disease severity.

Arthrography↗
PubMed1999

The postoperative shoulder.

Because disability and pain may persist or recur after shoulder surgery, visualization of the postoperative shoulder before further treatment is of great interest. Postoperative status is reevaluated most frequently after rotator cuff repair, capsulorrhaphy in patients with chronic instability, and acromioplasty, where postoperative symptoms are clinically difficult to distinguish from rerupture or inadequate surgical results. Postoperative evaluation or follow-up after surgical treatment of tumors or surgical repair of shoulder injuries are other potential indications. Whereas surgical procedures for osseous components primarily will be evaluated by plain film radiographs, magnetic resonance imaging is a valuable tool for other sites of surgical treatment, such as soft-tissue components, with further potential indication for magnetic resonance arthrography. This article focuses on normal and abnormal postoperative findings in the shoulder, with emphasis of magnetic resonance imaging, and discusses specific findings based on magnetic resonance arthrography.

Acromion↗
PubMed1999

Magnetic resonance imaging of the postoperative hip.

Magnetic resonance imaging (MRI) of the postoperative hip for delineation of various pathological conditions has been established in addition to conventional radiography and computed tomography. MRI provides superior soft-tissue contrast than the other imaging modalities, and it can be used for visualization of structures and pathological entities that cannot be depicted by conventional radiography and computed tomography. These entities include bone marrow changes such as bone marrow edema and avascular necrosis, and infiltration of the bone marrow by tumor recurrence or infections after insertion of metallic osteosynthetic material. The image quality of MRI, which is reduced as result of artifacts caused by metal alloys, can be optimized by using spin-echo or fast spin-echo sequences, and by adapting phase- and frequency-encoding directions in cases where metallic osteosynthetic materials were used. MRI, in addition to computed tomography and conventional radiography, appears to be a valuable tool for imaging the different pathological conditions of the postoperative hip, including after implantation of metallic osteosynthetic material.

Arthroplasty, Replacement, Hip↗
PubMed1999

Magnetic resonance imaging of the postoperative knee.

Due to the recent development of arthroscopic techniques in meniscal surgery and anterior cruciate ligament reconstruction, an increasing number of postoperative patients are referred for a magnetic resonance examination of the knee because of recurrent injury. Contrary to the nonoperative patient, T2-weighted sequences and, in unequivocal cases, magnetic resonance arthrography play the most important role in the evaluation of a possible meniscal retear. In patients with anterior cruciate ligament reconstruction, the changes of the magnetic resonance appearance of the anterior cruciate ligament graft during the first year after surgery must be considered in the diagnosis of retears. Recent developments in articular cartilage defect repair and the possible role of magnetic resonance imaging in the follow-up are discussed.

Anterior Cruciate Ligament↗
PubMed1999

Posturographic findings in patients with idiopathic cervical dystonia before and after local injections with botulinum toxin.

In this posturographic study, whole-body postural control was impaired in more than 75% of patients with idiopathic cervical dystonia (ICD) before local injections with botulinum toxin type A (BTX-A) and the impairment was independent of the direction of the torticollis. Six weeks after therapy with BTX-A, the number of pathological posturographic parameters had decreased by almost 30%, and the improvement reached statistical significance for sway path, sway area and anteroposterior sway during stance on foam with eyes closed. From a pathophysiological point of view, this improvement may be explained - at least in part - by a reduction of abnormal proprioceptive input from the neck. Accordingly, it seems possible that neck proprioceptive input plays a role in whole-body postural control in ICD patients, even though previous studies suggested that the neck input is relatively ignored in these patients.

Adult↗
PubMed1999

[Chronic diseases of the ankle joint].

The etiology of chronic diseases of the ankle joint comprises a wide spectrum including chronic inflammatory processes and chronic degenerative, tumorous and neuropathic processes, as well as some specific syndromes based on chronic changes of the ankle joint. Of the inflammatory processes, chronic juvenile arthritis (JVC) is the most common disease. However, also Reiter disease, psoriasis or chronic monoarthritid diseases such as gout, as well as granulomatous diseases (tuberculosis, sarcoidosis) and fungal infections, may affect the ankle joint in a chronic course. Chronic degenerative changes are usually secondary due to abnormal positioning of the joint constituents or repetitive trauma. Neuropathic changes, as frequently seen in the course of diabetes, present with massive osseous destruction and malposition of the articular constituents. Chronic osseous as well as cartilaginous and synovial changes are seen in hemophilic patients. Chronic traumatic changes are represented by pigmented villonodular synovitis (PVNS), and chondromatosis, both with a predilection for the ankle joint. Due to the possibilities of magnetic resonance imaging (MRI), diagnosis of chronic ankle changes includes chronic ligamentous, tendinous and soft tissue changes. With the use of MRI, specific syndromes can be defined which particularly affect the ankle joint in a chronic way, such as the os trigonum syndrome, the anterolateral impingement syndrome and the sinus tarsi syndrome. Nevertheless, plain film radiographs are still the basic element of any investigation. MRI, however, can be potentially used as a second investigation, saving an unnecessary cascade of investigations with ultrasound and CT. The latter investigations are used only with very specific indications, for instance CT for subtle bone structures and sonography for a limited investigation of tendons or evaluation of fluid. Particularly due to the possibilities of MRI and the development of special gradient-echo imaging or high-resolution coils, the investigation of the ankle joint still offers a wide spectrum of innovation for the next years, which is particularly enforced by the increasing demand for specific diagnosis of chronic diseases in orthopedic medicine.

Adolescent↗
PubMed1999

Elastofibroma dorsi. Study of two cases and magnetic resonance imaging findings.

Two cases of elastofibroma dorsi (one bilateral, one unilateral) in the periscapular and infrascapular region of two male patients are described. Magnetic resonance imaging revealed a tumorous mass of typical low signal intensity with interspersed areas of high signal intensity on T1 and T2 weighted spin echo sequences. In contrast to previous studies that reported mild enhancement within elastofibromas after administration of intravenous contrast agent, marked enhancement in one of two elastofibromas was found. This is considered to be atypical for benign lesions. After biopsy and histopathologic examination, an intended marginal resection was performed in both cases. Laboratory values, radiographs, and computed tomography may not be helpful in differentiating elastofibroma from malignant tumors. In addition to careful clinical investigation, magnetic resonance imaging is the method of choice leading to a presumptive diagnosis. Because marked enhancement on contrast agent images was observed, which is characteristic for malignant tumors, one should be aware that this feature does not exclude the presence of elastofibroma. Accurate diagnosis should be made preferably by biopsy and histopathologic evaluation before additional treatment is administered. Marginal resection is curative in patients with symptoms. Despite its low incidence, this pseudotumoral lesion should be known generally to differentiate it from malignant tumors and to avoid unnecessary wide or radical surgery.

Back↗
PubMed1999

Influence of radiation synovectomy on articular cartilage, synovial thickness and enhancement as evidenced by MRI in patients with chronic synovitis.

UNLABELLED: Radiation synovectomy is a safe and effective treatment for chronic synovitis that is refractory to the repetitive, intra-articular application of glucocorticosteroids in patients with rheumatoid or seronegative arthritis. Short-term and long-term effects of radiation synovectomy on articular cartilage, synovial enhancement and thickness were assessed in a prospective, clinical trial by MRI. METHODS: Thirteen patients (mean age 39+/-13 y) were treated with a median activity of 8.4 GBq 165Dy ferric hydroxide, a radionuclide with favorable physical properties and a well-documented clinical safety and efficacy profile. MRI was performed on a 1.5-T MR unit using a circular polarized knee coil. RESULTS: After a mean observation period of 13 mo, a marked reduction in synovial enhancement was observed in 10 patients. The mean reduction in baseline synovial thickness (mean 7.6+/-3.0 mm) was 24% (P = 0.03) at 1 wk and 42% (P = 0.01) about 1 y after treatment, respectively. Clinically, 9 of 13 patients (69%) exhibited persistent response to radiation synovectomy. The local clinical score, as defined by the reduction in pain, pannus, joint effusion and by the increase in the range of motion, improved significantly (P = 0.01), from a median of 7 (range 4-10) to a median of 2 (range 0-9). One year after treatment, changes in the local clinical score were related to the decrease in synovial enhancement in MRI (r = 0.7, P = 0.008, n = 12). There were no persistent adverse effects, nor was there evidence for any severe radiation-induced damage to the articular cartilage. On later follow-up images, the structure of the articular cartilage remained unaltered in all but 3 patients, who had new, superficial erosions most likely attributed to an active disease with persistence of inflammation. CONCLUSION: This study suggests that radiation synovectomy with 165Dy-ferric hydroxide is effective in terms of reducing chronic synovitis without causing detectable harm to the articular cartilage, as shown by MRI.

Adult↗
PubMed1998

[Prospective comparison of MRI vs. direct magnification radiography in occult fractures of the scaphoid bone].

The diagnosis of occult fractures of the scaphoid bone is even more challenging than that of conventional fractures of the scaphoid. This study aimed to compare prospectively the gold standard method (plain radiographs in four projections, after about 14 days) and the primary findings with direct magnification radiography (DIMA) and magnetic resonance imaging (MRI). Primary MRI showed much higher diagnostic power than plain radiography at 10-14 days in occult scaphoid fractures and in detection of associated carpal injuries. This may lead to a decreasing time of disease. DIMA was inferior in detecting occult fractures of the scaphoid.

Adolescent↗
PubMed1998

Morphological dissociation between visual pathways and cortex: MRI of visually-deprived patients with congenital peripheral blindness.

MRI was used to study possible morphological changes in the visual system in 12 patients suffering from congenital blindness of peripheral (ocular) origin. While their optical pathways showed degeneration, hypoplasia or atrophy in 7 out of 12 cases, the occipital cortex appeared normal in all cases. This dissociation between afferent pathways and the cortex is contrary to the assumption that visually deprived cortex may undergo degeneration. The finding is congruent with evidence that the occipital cortex is used for other, nonvisual functions.

Adult↗
PubMed1998

Kinking and stenosis of the carotid artery associated with homolateral ischaemic brain infarction in a patient treated with cyclosporin A.

UNLABELLED: We present a 3-year-old patient with stenotic kinking of the left internal carotid artery (ICA) who developed an ischaemic infarction of the left brain hemisphere followed by severe neurological sequelae after a prolonged generalized seizure. At time of the seizure the boy was in biological remission of a nephrotic syndrome and received prednisolone and cyclosporin A (CsA) treatment. The haemodynamic consequences of inborn kinking of the ICA is discussed controversely in the literature. The presented case shows that stenotic kinking of the ICA may significantly impair the blood flow towards the homolateral hemisphere and therefore may result in an ischaemic infarction. The influence of CsA on seizure activity is discussed. CONCLUSION: This case provides clinical and radiological evidence supporting an association between stenotic kinking of the carotid artery and homolateral hemispheric brain infarction.

Carotid Artery, Internal↗
PubMed1998

[Dental magnetic resonance tomography (dental MRI) as a method for imaging maxillo-mandibular tooth retention structures].

PURPOSE: To establish a new method for dental imaging using magnetic resonance tomography named Dental-MRT and to demonstrate its usefulness in diagnosing dentogen pathologies of the mandible and maxilla. METHODS: Seven healthy volunteers, three patients with pulpitis, two patients with dentigerous cysts, two patients after tooth transplantation, and three patients with atrophic mandibles have been evaluated. Optimized axial T1- and T2-weighted gradient echo and spin echo sequences in 2D and 3D technique have been established to perform studies of the jaws. The acquired images were reconstructed with a standard dental software package on a work-station as panorama and cross-sectional views of the mandible or maxilla. RESULTS: The entire maxillo-mandibular bone, teeth, dental pulp, and the content of the mandibular canal were well depicted. Patients with pulpitis demonstrate bone marrow edema in the periapical region. Dentigerous cysts and their relation to the surrounding structures are clearly shown. After contrast media administration marked enhancement of the dental pulp can be demonstrated. CONCLUSION: Dental-MRT promises to provide a new tool for visualization and detection of dental diseases.

Adolescent↗
PubMed1998

MR imaging in shoulder trauma. Value of STIR images.

PURPOSE: To determine the adequacy of MR standard protocols by analyzing conventional T1- and T2-weighted SE sequences, and to evaluate the usefulness of additional fat-suppressed (STIR) images in shoulder trauma. MATERIAL AND METHODS: Paracoronal T1-weighted, T2-weighted, SE, and STIR images were obtained on a 0.5 T superconductive system in 25 patients with shoulder trauma. In a separate evaluation of T1/T2 images and a combined evaluation of T1/T2 SE- and STIR images, we compared the number of patients with evidence of Hill-Sachs lesions, bone bruises, and/or rotator-cuff lesions. RESULTS: Compared to the combined evaluation of T1/T2 and STIR images, the separate evaluation of T1/T2 SE images revealed identical results for rotator-cuff lesions and Hill-Sachs lesions, but different results for the bone bruises in the area of the major tubercle. CONCLUSION: Occult fractures of the major tubercle, indicated by areas of bone bruising, might be missed with MR using conventional SE images. We recommend the use of additional paracoronal fat-suppressed sequences in patients with clinically suspected lesions and equivocal findings on plain radiographs and on standard SE sequences.

Adult↗
PubMed1998

MR imaging of the inner ear and cerebellopontine angle: comparison of three-dimensional and two-dimensional sequences.

OBJECTIVE: The aim of the study was to compare the ability of three-dimensional (3D) T2-weighted turbo spin-echo and gadolinium-enhanced 3D T1-weighted gradient-echo sequences with two-dimensional (2D) T2-weighted turbo spin-echo and gadolinium-enhanced T1-weighted spin-echo sequences to reveal anatomic and pathologic structures of the inner ear and cerebellopontine angle. SUBJECTS AND METHODS: Thirty-one patients underwent axial 2D T2-weighted turbo spin-echo and 3D T2-weighted turbo spin-echo MR imaging, axial and coronal 2D T1-weighted spin-echo MR imaging before and after i.v. injection of gadopentetate dimeglumine, and gadolinium-enhanced axial 3D T1-weighted gradient-echo MR imaging. The visualization of anatomic and pathologic structures on the different sequences was evaluated. Statistical analysis was performed from the data obtained from the visual evaluation of the anatomic structures on the different sequences. Signal-to-noise and contrast-to-noise ratios were calculated for the gadolinium-enhanced 3D T1-weighted gradient-echo and 2D T1-weighted spin-echo sequences, and statistical evaluation was performed. RESULTS: The 3D sequences enabled excellent visualization of 94% of all evaluated anatomic structures, and the 2D sequences enabled excellent visualization in only 3% of these structures. Pathologic structures were revealed in all cases by one or both of the 3D sequences. Diagnosis in all patients could be made by using the combination of the 3D T2-weighted turbo spin-echo and the gadolinium-enhanced 3D T1-weighted gradient-echo sequences. However, the 2D sequences failed to show pathologic structures in three patients. We found a significant statistical difference for the visualization of anatomic structures with the 3D and 2D sequences (p < .0001) and no significant statistical difference for the signal-to-noise and contrast-to-noise ratios with the 3D T1-weighted gradient-echo and 2D T1-weighted spin-echo sequences. CONCLUSION: The 3D sequences revealed anatomic structures significantly better than did the 2D sequences and showed pathologic structures considerably more often than did the 2D sequences in all patients. MR imaging of the inner ear and cerebellopontine angle performed with 3D T2-weighted turbo spin-echo and gadolinium-enhanced 3D T1-weighted gradient-echo sequences provided the most accurate imaging leading to diagnosis in cases of abnormality.

Adult↗
PubMed1997

[MRI on low-field tomography systems (0.2 Tesla). A quantitative comparison with equipment of medium-field strength (1.0 Tesla)].

AIM OF THE STUDY: Using phantom studies, a dedicated low-field MR system with 0.2 T and a whole-body MR-scanner with 1.0 T were compared. METHODS: A spin-echo sequence was performed on the 0.2-T MR unit using the knee coil and on the 1.0-T MR unit with the head coil. In a water-filled phantom, signal-to-noise ratios (SNR) were calculated and contrast measurements on gels with well-defined relaxation times were obtained and compared to nominal relaxation times. Measurements of T1 and T2 relaxation times on the low-field system were compared to the 1.0-T unit. As a parameter for geometrical image quality, magnetic field distortions were calculated. In theory, influence of field strength and and receiver bandwidth on the minimal echo time and on chemical shift artifacts were calculated. RESULTS: The SNR was 63.2 on the 0.2-T and 179.6 on the 1.0-T MR unit (difference factor 3, against a theoretical difference of 5-16). Relaxation times on the low-field system were significantly (around 40-50%) lower. Measurements of contrast were similar on both systems. On the low-field system geometrical distortions of several pixels were recorded. The minimal echo time on the low-field system was 21.3 ms with the low receiver bandwidth and 4.3 ms on the 1.0-T MR unit. The amount of chemical shift artefacts was the same on both systems. DISCUSSION: On low-field MR systems SNR is markedly improved by small read-out gradients and a low receiver bandwidth (factor 3 vs 5-16 in comparison with the 1.0-T MR unit). However, an optimal homogeneous magnetic field is required, since inhomogeneities may create severe geometrical distortion.

Artifacts↗