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T Vogl

Publications and source records attributed to T Vogl.

At least 91 records · Page 5Linked to original sources
PubMed1995

[Comparison of the diagnostic value of CT and MRI in injuries of the cervical vertebrae].

The aim of our study was to compare the diagnostic capacities of computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnostic evaluation of acute cervical spinal column injuries. We examined 39 patients with cervical spine injury suspected either clinically or by plain radiography, or even confirmed. In 30 patients, 86 acute traumatic lesions were observed in the area of the cervical spine, 83% of which were retrospectively recognisable by CT and 95% on MRI films. In nine patients, no acute traumatic pathologic pattern could be found either by CT or by MRI or any other subsequently employed diagnostic methods. CT yielded 100% of the osseous acute traumatic findings, the degenerative lesions narrowing the spinal channel, and of the dislocations, but only 33% of the lesions of the longitudinal ligaments, 50% of intramedullary haemorrhages, 60% of paravertebral soft tissue haematomas, 83% of vertebral disc herniations of protrusions, and none of the six nonhaemorrhagic spinal cord contusions. Without exception, MRI revealed all the traumatic medullary and paravertebral soft tissue changes, dislocations, and spondylophytes narrowing the spinal channel, but only 50% of the C2-odonteous fractures, 89% of the transverse processes', and 92% of the vertebral lamina fractures. Basing on these results, after primary plain film radiograph imaging, the performance of MRI seems to be recommendable prior to CT in diagnostic evaluation of traumatic cervical spinal lesions, if possible with regard to the patient's clinical state and the global organization, unless immediate CT imaging of other body regions (i.e. of the head) is already being planned anyway, Nevertheless, MRI should not be abandoned within the overally framework of this disease pattern.

Adult↗
PubMed1995

Muscle edema in MR imaging of neuromuscular diseases.

Muscle edema has been described as a typical finding on MR images in acute neuromuscular disorders, predominantly in acute inflammatory myopathies, but also in neuro- and myopathies. The purpose of this study was to examine the frequency of muscle edema and the diagnostic usefulness of Gd-DTPA in neuromuscular diseases. 144 consecutive patients with various generalized neuromuscular diseases were examined by MR imaging. Areas of high signal intensity, relative to normal muscle, were seen in 36% of T2-weighted images, whereas the corresponding T1-weighted images showed normal or lower signal intensities. These edema-like abnormalities--enlargement of the extracellular fluid space--were found more often in inflammatory and metabolic myopathies, but were also seen in degenerative myopathies. Contrast-enhanced T1-weighted images in 25 patients were not more sensitive than plain T2-weighted images.

Acute Disease↗
PubMed1995

[Diagnostic significance and therapeutic consequences of computerized tomography (patient outcome research). II: General surgical diagnosis].

Computed tomography is one of the indispensable diagnostic methods in the treatment of many surgical patients. On the other hand, the high cost of equipment and effort and the expensive examination must be taken into account. For the purposes of a patient-outcome study all CT examinations of surgical patients performed in March to May 1993 were analysed under medical and economic aspects. 49% of the 210 examinations (153 patients) were primary examinations, 51% served as control examinations. In 61% the diagnosis was already known, but additional information with decisive influence on the further treatment was obtained. In 17% the supposed diagnosis could be verified and in 22% it was rejected. In 170 examinations (81%) the necessity of an operation was the question. 53% of all CT examinations revealed that indication for an operation was absent, and in 28% an operative intervention was performed. The CT examination of surgical patients cannot be substituted by lower-cost methods. The use of an efficient planning of the therapeutic procedures, shortcutting of many other diagnostic examinations, and the avoidance of unnecessary surgical interventions result in shortening the duration of treatment and are instrumental in reducing the total treatment cost.

Adult↗
PubMed1995

[Diagnostic value and therapeutic consequences of computerized tomography (patient outcome research)--1: Diagnosis in traumatology].

During three months of 1993, 201 primary traumatologic patients (125 m, 76 f, x = 42.6 years) underwent 230 computed tomography examinations (= one CT of one body region) in the radiologic department of the Rudolf Virchow University Hospital. 87.0% of the CT's were performed completely without contrast media, 2.6% exclusively supported by intravenously given contrast media, 9.1% in both ways, and 1.3% after intra-articular contrast media administration. 97.4% served for primary diagnostic purposes and 2.6% for the control of therapeutic results. In 47.8% of the CT's, the principle diagnosis in the scanned body region was known before CT, i.e. by conventional X-ray examinations, but further detailed information was necessary to clarify the indication for operation and to choose the operative mode. In 52.2%, the diagnosis without CT was impossible by other, non-invasive and not more expensive methods. The CT diagnoses were correctly positive in 58.7% (suspected diagnosis verified, additional detail information...) and correctly negative in 41.3% (suspected diagnosis excluded). 60.9% of CT's demonstrated a missing indication for operation in the examined body region; in 39.1% the operation followed. The most frequently performed diagnostic methods before CT were conventional X-ray and sonography, whereas after CT further examinations were seldom needed. We conclude that traumatologic CT's contribute decisively to the reduction of costs by avoiding more expensive examination methods, avoiding redundant operations, and abridging stay duration in the hospital because of more efficient therapy planning.

Abscess↗
PubMed1994

Clinical progressive supranuclear palsy: differential diagnosis by IBZM-SPECT and MRI.

In order to in vivo identify subgroups in eight patients with the clinical diagnosis of progressive supranuclear palsy (PSP), we have performed 123I-iodobenzamide single photon emission computed tomography (IBZM-SPECT), a nuclear medicine technique, to visualize dopamine D2 receptors in vivo, and high resolution (TE/TR 2900/20-90) magnetic resonance imaging (MRI) to evaluate morphological CNS changes. All patients exhibited similar clinical features including supranuclear vertical gaze palsy, especially of downward gaze, predominantly axial rigidity especially in the neck, bradykinesia, instability of balance with easy falls, and poor response to dopaminergic drugs. Specific striatal dopamine D2 receptor binding in IBZM-SPECT, as calculated by a basal ganglia to frontal cortex ratio (BG/FC) was reduced in 5 patients, but normal in 3 patients. In MRI, these 3 patients exhibited multiple hyperintense white matter lesions; 2 of them had no midbrain atrophy. In contrast, all 5 patients with reduced IBZM binding lacked multiple white matter lesions in MRI, but 4 of them showed marked midbrain atrophy. This pilot study with IBZM-SPECT for in vivo imaging of striatal dopamine D2 receptors and T2-weighted MRI supports published neuropathological findings that clinical signs of PSP appeared to be due to heterogeneous neuropathology.

Aged↗
PubMed1994

An alternative interpretation of the heat capacity changes associated with protein unfolding.

The present study devises a method to get quantitative information for proteins on the theoretically important heat capacity at constant volume. For this purpose expansion coefficients of both the native and unfolded state of a variety of proteins have been determined and used together with compressibility coefficients to calculate the difference between isobaric and isochoric heat capacity, (cp - cv), for the unfolding transition. This difference delta (cp - cv) = (c - c) - (c - c) turns out to be a positive number that is larger than the experimental isobaric heat capacity change (formula:see text) [corrected] for the proteins studied. The generally observed positive heat capacity change on unfolding can therefore alternatively be interpreted as resulting from the difference in work involved in changing the intra- and intermolecular interactions including the weak, highly distance-dependent, van der Waals interactions, for the unfolded and native state, respectively. The difference in expansion work against the atmospheric pressure is negligible. This macroscopic interpretation cannot rule out that part of the denaturational heat capacity increase is also due to the different interaction with water of the native and unfolded conformations of the protein.

Calorimetry↗
PubMed1994

[Improved diagnosis of stress fractures with contrast MRI].

MRI is of growing importance for diagnosing bone pathology. Application of additional gadolinium-DTPA contrast medium allows safe differentiation of stress fractures from pathological fractures due to the characteristic perifocal contrast enhancement in the T1 sequences. This phenomenon is exemplified by a case report of a stress fracture of the femoral neck in a long-distance runner.

Adult↗
PubMed1994

[Non-squamous epithelial malignancies of the larynx with special reference to MRT diagnosis].

Non-squamous malignancies of the larynx are extremely rare, usually subsurface in origin and mostly diagnosed only in an advanced stage. Two cases representative of this group are described, namely, an adenoid cystic carcinoma and a pleomorphic rhabdomyosarcoma. The clinicopathological data of these unusual tumours are presented and the current therapeutic modalities discussed. The diagnostic value of MRI with contrast medium is emphasised by demonstrating an otherwise not recognised far advanced tumour stage. The pleomorphic rhabdomyosarcoma was also examined via electron microscopy.

Carcinoma, Adenoid Cystic↗
PubMed1994

[Cystic lymphoepithelial lesions in the head and neck area in HIV-infected patients].

Benign lymphoepithelial cysts (BLC) are rare disorders of salivary glands (0.6%). In patients infected by HIV, they are seen more often. In comparison to sporadic BLC, the patients are younger, the diameter of the cysts is up to 5 cm and they are often located bilaterally. At the Department of ENT, Head and Neck Surgery of the Ludwig-Maximilians-University, Munich, ten HIV-infected patients (two females) showed lymphoepithelial cysts (six times bilaterally). One of these revealed a metastasis of a small cell neoplasma near the cysts, another patient showed a non-Hodgkin's lymphoma of low grade malignancy (MALT-type), and one patient additionally had bilateral Warthin's tumours. The BLCs were mostly located in the parotid tail. In three cases, the cysts were found on the inferior border of the parotid and once at the submandibular gland. The age ranged from 27 to 71 years (medium 45.7 years). The mode of HIV infection was homosexuality five times, drug abuse twice, heterosexuality once, and blood products once. In two cases, the channel of transmission was unknown. The majority of the patients showed minor HIV illness (CDC II [n = 2]/CDC III [n = 4]); the rest had advanced immunodeficiency (CDC IV [n = 4]). All the cysts were examined by ultrasonography and NMR. According to the clinical findings and the general stage of health, BLCs were either enucleated (n = 8) or a superficial parotidectomy (n = 5) and selective biopsy of lymph nodes (n = 3) suspected to be malignant were performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Arteria lusoria--a rare cause of dysphagia].

A rare case of a 29-year old woman with aberrant right subclavian artery (A. lusoria) causing dysphagia is presented. This abnormality is generally silent and often an incidental x-ray finding. By means of a median thoracotomy the anomalous vessel was divided at its point of origin and an anastomosis to the ascending aorta with a graft was performed.

Adult↗
PubMed1994

Cerebral involvement in McLeod syndrome.

McLeod syndrome is an Xp21-linked Kell blood group variant due to lack of erythrocyte protein Kx with associated RBC membrane dysfunction such as acanthocytosis. A man with this syndrome developed chorea and slight neuropsychological impairment. He had caudate atrophy on cerebral imaging and reduced striatal dopamine D2-receptor binding on single-photon emission computed tomography. Since Xp21 was partly deleted in the patient, the missing gene product (possibly Kx) may be essential for the integrity of the striatum.

Benzamides↗
PubMed1994

Treatment with D-penicillamine improves dopamine D2-receptor binding and T2-signal intensity in de novo Wilson's disease.

We report the results of in vivo striatal dopamine D2-receptor binding assessed by PET using 11C-raclopride (only one patient) and by single-photon emission computed tomography (SPECT) using 123I-iodobenzamide (123I-IBZM) and the findings of T2-weighted MRIs in two de novo Wilson's disease patients before and 4 months after initiation of D-penicillamine treatment. Before treatment, specific 11C-raclopride binding (only patient 1) was markedly reduced, with a putamen to cerebellum ratio of 1.99 (controls: 3.99 +/- 0.55, n = 15) and a caudate to cerebellum ratio of 2.52 (controls: 3.65 +/- 0.59, n = 15). Specific 123I-IBZM binding was reduced in both patients, with a basal ganglia to frontal cortex ratio of 1.25 (patient 1) and of 1.41 (patient 2) controls: 1.57 +/- 0.04, n = 5). After 4 months of therapy, 11C-raclopride-PET improved to a putamen to cerebellum ratio of 2.52 and a caudate to cerebellum ratio of 3.06 (patient 1). 123I-IBZM-SPECT revealed an increase of basal ganglia to frontal cortex ratios of 1.34 (patient 1) and 1.55 (patient 2). On heavily T2-weighted MRI sequences, hyperintense signal changes before therapy within the putamen (both patients), brainstem (only patient 1), and caudate (only patient 2) greatly diminished after treatment. Reduced striatal dopamine D2-receptor binding in these Wilson's disease patients improved under therapy, suggesting, in part, a reversible defect of striatal neurons.

Adolescent↗
PubMed1994

Characterization of recombinant proteins: biochemical and biophysical criteria for the identity of native and renatured human tissue plasminogen activator and its mutants.

Rapid progress in recombinant DNA techniques has led to the production of a great variety of native and modified proteins in bacteria which, however, frequently occur in non-native conformations or in aggregated form. Renaturation methods must necessarily include criteria for the confirmation of the native structure and function of the refolded macromolecules. This Review describes some of the spectroscopic and thermodynamic techniques which can provide powerful tests for the identity of native and renatured proteins. Emphasis was laid on the concentration requirements of the methods and on the ease of application and availability of instrumentation. As an example we used the single-chain recombinant tissue plasminogen activator (rt-PA) at different pH values and buffer systems. t-PA is a monomeric serine proteinase of M(r) 68,000 that converts plasminogen into plasmin, thereby promoting the degradation of the fibrin network. This enzyme is a promising candidate for thrombolytic therapy of acute myocardial infarction. On the basis of the cDNA sequence the 527 amino acids of t-PA are likely to occur in five distinct structural domains. Specifically we exemplify the application of microcalorimetric studies for the verification of structural identity on rt-PA.

Amino Acid Sequence↗
PubMed1994

[Magnetic resonance applied to the diagnosis of Sjogren disease].

In order to characterize typical MRI-findings in patients with Sjögren's syndrome who present recurrent parotid swelling 15 patients with clinical diagnosis of this disease were examined in a prospectives study. Most of the patients showed bilateral enlarged glands with an inhomogeneous, nodular pattern. The signal intensity was very high, especially in the T2 weighted sequences.

Adult↗
PubMed1994

[Superparamagnetic iron particles. The clinical results in the MR diagnosis of liver metastases].

The diagnostic value of superparamagnetic iron particles as a tissue-specific MR contrast medium of the reticulo-endothelial system was studied in 30 patients. All patients had liver metastases (maximally 5 known metastases on MR). The patients were examined on a 1.5 Tesla scanner before and after a slow intravenous injection of iron particles (AMI-25) at a dose of 15 mumol/kg. Contrast injection led to a significant reduction of signal strength in the liver parenchyma (p < or = 0.001) but not in the metastases. Contrast enhanced spin echo sequences (SE 2300/45) provided the most marked liver/tumour contrast, greater than the contrast values of T1- and T2-weighted images (p < or = 0.01). After the intravenous injection of iron particles, small metastases in particular are more easily demonstrated. A new, rapid T2-weighted pulse sequence (PSIF 10/15/15 degrees) results in the elimination of vascular signals and leads to better differentiation between lesions and intrahepatic vessels. The use of superparamagnetic iron particles as an MR contrast medium improves the demonstration of liver metastases.

Contrast Media↗
PubMed1993

Endovascular treatment of traumatic arterio-venous fistulas of the vertebral artery.

Cervical vertebral artery fistulas are rare arteriovenous malformations between the vertebral artery and veins of the neighbourhood. The etiology of the fistulas may be traumatic or spontaneous. Management and the results in two patients with large arterio-venous fistulas of the cervical vertebral artery with severe deterioration of spinal function by using the detachable balloon technique are discussed. Complete angiographic and clinical cure was achieved in both patients and no complications related to the embolization procedure occurred. The detachable balloon technique is an effective method for selective occlusion of the fistula. Good radiographic monitoring facilities are required to make endovascular procedures effective and safe.

Adult↗