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S Dresel

Publications and source records attributed to S Dresel.

At least 37 records · Page 2Linked to original sources
PubMed2000

Clinical and biological findings in a case with 48-hour bipolar ultrarapid cycling before and during valproate treatment.

BACKGROUND: The rare cases of patients with 48-hour ultrarapid cycling allow close investigation of mood cycles in affective disorders, because rhythmic changes in psychopathologic state and biological parameters happen very precisely. METHOD: A 67-year-old white man who had experienced bipolar 48-hour ultrarapid cycling (DSM-IV 296.80) for several years was studied without any medication and then again studied 4 weeks later during treatment with valproate (1800 mg/day). RESULTS: Objective and self ratings revealed pronounced manic states 1 day and depressed states the following day, which were found to be accompanied by rhythmic fluctuations in behavior and electroencephalographic parameters, blood cortisol and growth hormone levels (both elevated on depressive days), and urinary metanephrine (dopamine metabolite) and norepinephrine levels (both elevated on manic days). Using single photon emission computed tomography, regional blood flow in the left thalamus was lower than in the right thalamus on the manic day, while symmetric perfusion of the thalamus was found on the depressive day. Under valproate treatment, the patient remitted completely, and significant rhythmic changes in most of the biological parameters were no longer detectable. CONCLUSION: The biological findings in this patient with bipolar 48-hour ultrarapid cycling, which correspond to those in other types of affective disorders, suggest that disturbances in the diencephalon-pituitary axis may be especially correlated to pathologic changes of mood.

Aged↗
PubMed2000

Quantitative comparison of automatic and interactive methods for MRI-SPECT image registration of the brain based on 3-dimensional calculation of error.

UNLABELLED: A wide range of techniques for registration of medical images has been devised in recent years. The aim of this study is to quantify the overall spatial registration error of 3 different methods for image registration: interactive matching, surface matching, and uniformity index matching as described by Woods. METHODS: MRI and ethylcysteinate dimer-SPECT images of the brain were registered for 15 patients. The matching error was assessed by determining intra- and interobserver variability of registrations. Quantification of the registration error was based on the mean spatial distance of 5000 voxels between 2 image positions. The mean position after repeated registrations in each patient was used as the gold standard. To evaluate the coherence of the 3 different registration methods, intermethod variability was determined. RESULTS: Interactive matching showed an intraobserver/interobserver variability of 1.5+/-0.3 mm/1.6+/-0.3 mm (mean +/- SD). The time demand for this method was 11+/-5 min. Surface matching revealed a variability of 2.6+/-1.1 mm/3.8+/-1.0 mm and a time demand of 26+/-12 min. Reproducibility of Woods' algorithm was 2.2+/-0.8 mm with a time demand of 9+/-3 min. In 4 of the 15 cases, Woods' method failed. The mean deviation between all 3 methods was 2.3+/-0.8 mm. CONCLUSION: With a suitable user interface, interactive matching had the lowest registration error. The influence of subjectivity was shown to be negligible. Therefore, interactive matching is our preferred technique for image fusion of the brain.

Adult↗
PubMed2000

[Metastases in malignant melanoma despite histologically negative sentinel lymph node: should the concept be changed?].

AIM: The Sentinel Lymph Node (SLN) is of considerable prognostic relevance, because extended lymph node dissection may not be performed in patients presenting with histologically negative SLN. The aim of the present study was to prove the prognostic value of the SLN-concept in these patients. METHODS: So far the clinical follow-up of 162 patients with histologically proven malignant melanoma and metastatically uninvolved (negative) SLN was investigated. Histological examination included standard methods (HE-Test) and special histochemical techniques (S-100, HMB-45). All patients underwent clinical examination, ultrasonic diagnosis of the regional lymph nodes, and x-ray of the chest every 3 months. RESULTS: Despite of negative SLN-findings in 8/162 patients metastases of the malignant melanoma were found after a time period of 5-27 months. Three patients presented with recurrence in the previously mapped (negative) SLN-basin. In another case the scintigraphically visualized SLN could not be identified intraoperatively by means of the hand-held gamma probe. One patient showed intransit-metastases or skin-metastases, respectively; another patient recurred in the scar area. One patient showed hematogenic dissemination (liver) which is not detectable by lymphoscintigraphy; in another patient metastases were found outside the primary lymphatic basin (cervical). CONCLUSION: In our patient group 4.9% presented with metastases despite negative SLN while published data report up to 11% (observation period 35 months), among them only 3 patients (1.9%) being real concept failures. Our results underline that there is no evidence to change this concept in patients with clinically early stage.

Adult↗
PubMed1999

In vivo effects of olanzapine on striatal dopamine D(2)/D(3) receptor binding in schizophrenic patients: an iodine-123 iodobenzamide single-photon emission tomography study.

Olanzapine is a new atypical antipsychotic agent that belongs to the same chemical class as clozapine. The pharmacological efficacy of olanzapine (in contrast to that of risperidone) has been shown to be comparable to that of clozapine, but olanzapine has the advantage of producing a less pronounced bone marrow depressing effect than clozapine. The specific aims of this study were (a) to assess dopamine D(2)/D(3) receptor availability in patients treated with olanzapine by means of iodine-123 iodobenzamide [(123)I]IBZM single-photon emission tomography (SPET), (b) to compare the results with findings of [(123)I]IBZM SPET in patients under treatment with risperidone and (c) to correlate the results with the occurrence of extrapyramidal side-effects (EPMS). Brain SPET scans were performed in 20 schizophrenic patients (DSM III R) at 2 h after i.v. administration of 185 MBq [(123)I]IBZM. Images were acquired using a triple-head gamma camera (Picker Prism 3000 XP). For semiquantitative evaluation of D(2)/D(3) receptor binding, transverse slices corrected for attenuation were used to calculate specific uptake values [STR-BKG]/BKG (STR=striatum; BKG=background). The mean daily dose of olanzapine ranged from 0.05 to 0.6 mg/kg body weight. The dopamine D(2)/D(3) receptor binding was reduced in all patients treated with olanzapine. Specific IBZM binding [STR-BKG]/BKG ranged from 0.13 to 0.61 (normal controls >0.95). The decreased D(2)/D(3) receptor availability revealed an exponential dose-response relationship (r=-0.85, P<0.001). The slope of the curve was similar to that of risperidone and considerably higher than that of clozapine as compared with the results of a previously published study. EPMS were observed in only one patient, presenting with the lowest D(2)/D(3) availability. The frequency of EPMS induced by olanzapine (5%) was considerably lower than the frequency under risperidone treatment (40%). Our findings suggest an exponential relationship between the daily dose of olanzapine striatal and decreased D(2)/D(3) striatal binding availability. The results are consistent with the findings of in vitro experiments reporting a higher D(2)/D(3) receptor affinity and a similar 5HT(2) receptor affinity of olanzapine as compared with clozapine. Thus, the decreased tendency to induce EPMS at therapeutic doses is not due to the limited occupancy of striatal D(2)/D(3) receptors in vivo. Patients are protected from EPMS by other intrinsic effects of the drug, i.e. the combination of both D(2)/D(3) and 5HT(2) receptor antagonism.

Adult↗
PubMed1999

Kinetic modeling of [99mTc]TRODAT-1: a dopamine transporter imaging agent.

UNLABELLED: [99mTc]Technetium[2-[[2-[[[3-(4-chlorophenyl)-8-methyl-8-azabicyclo [3.2.1] oct-2-yl]-methyl] (2-mercaptoethyl) amino] ethyl] amino] ethane-thiolato(3-)-N2,N2',S2,S2']oxo-[1R-(exo-exo)] ([99mTc] TRODAT-1) is a useful imaging agent for central nervous system dopamine transporters. The purpose of this study was to characterize the in vivo binding potential and kinetic rate constants of this agent in nonhuman primates. METHODS: A series of four SPECT scans were performed on each of two female baboons with a bolus injection of [99mTc]TRODAT-1 (717+/-78 MBq; 19.38+/-2.12 mCi). Dynamic images of the brain were acquired over 4 h using a triple-head camera equipped with fan-beam collimators. Arterial and venous blood were sampled frequently using a peristaltic pump throughout the duration of the study. Regions of interest were drawn on the corresponding MRI scan to which each functional image was coregistered. Using analytical solutions to the three-compartment model with the Levenberg-Marquardt minimization technique, each study was individually fitted to a kinetic parameter vector (method I). Additionally, within each subject, three corresponding intrasubject studies were fitted simultaneously to a single parameter vector by constraining the binding potential, distribution volume and dissociation rate constant to improve the identifiability of the parameter estimates (method II). RESULTS: The results clearly indicated that [99mTc] TRODAT-1 localized in the striatum with slower washout rate than other brain regions. A maximal target/nontarget ratio of 3.5 between striatum and cerebellum was obtained. SPECT image analysis of the striatum yielded unconstrained k3/k4 values of 3.4+/-1.4, 2.4+/-0.7, 3.0+/-1.5, and 4.0+/-10.3, with respective constrained (fixed k4) values of 2.9 +/- 0.4, 2.4 +/- 0.4, 1.7+/-0.4 and 1.8+/-0.4 in one baboon using method I. With method II, the corresponding simultaneously fitted values were 2.1+/-0.3 using no constraints and 2.2+/-0.2 using a fixed k4. The second baboon had similar results. CONCLUSION: These findings suggest that the binding potential and corresponding kinetic rate constants can be reliably estimated in nonhuman primates with dynamic SPECT imaging of the dopamine transporter using a technetium-based tropane analogue. Furthermore, method II parameter vectors compare favorably to those produced using method I based on SEEs.

Animals↗
PubMed1998

Iodine-123-iodobenzamide SPECT assessment of dopamine D2 receptor occupancy in riperidone-treated schizophrenic patients.

UNLABELLED: The recently introduced neuroleptic, risperidone, was expected to block fewer dopamine D2 receptors than typical neuroleptics (e.g., haloperidol), but at comparable potency. The aim of this study was to evaluate the degree of dopamine D2 receptor occupancy in relation to the neuroleptic dosage and to correlate the findings with the presence of extrapyramidal symptoms (EPS). Additionally, the data were compared to previous iodobenzamide (IBZM) SPECT findings in patients treated with other neuroleptics, haloperidol and clozapine. METHODS: In 20 patients with schizophrenia [Diagnostic and Statistical Manual of Mental Disorders (Third Edition-Revised)] treated with mean daily doses of risperidone ranging from 0.029 to 0.128 mg/kg body weight, SPECT was performed 2 hr after intravenous injection of 185 MBq 123I-IBZM, a selective dopamine D2 receptor ligand. Striatal IBZM binding was assessed by calculating a striatal/frontal cortex ratio, expressed as a percentage of the control value. RESULTS: Selective dopamine D2 receptor binding of the ligand was reduced in all treated patients, with binding values ranging from 7% to 68%. The degree of occupancy displayed an exponential dose-response relationship (r = -0.86; p < 0.0001). The slope of the curve was between those of haloperidol and clozapine but was closer and more similar in shape to the curve of haloperidol. Extrapyramidal symptoms were observed in 8 of 20 patients with binding values between 7% and 47%. However, there was no clear relationship between the degree of receptor occupancy and the presence of EPS. CONCLUSION: The findings suggest an exponential dose-response relationship between the daily dosage of risperidone and the dopamine D2 receptor occupancy. The blockade of specific striatal IBZM binding found under therapy with risperidone is between those of haloperidol and clozapine. The dose-response curve for risperidone, however, shows greater similarity to that of haloperidol.

Adult↗
PubMed1998

[Diagnosis of sentinel lymph node in malignant melanoma: preoperative lymphoscintigraphy and intraoperative gamma probe guidance].

AIM: The sentinel lymph node (SLN) has shown to reflect the histologic features of the remainder of the lymphatic basin in patients with melanoma and is of considerable prognostic relevance. Aim of the study was to localize the SLN pre and intraoperatively by means of lymphoscintigraphy and gamma probe guidance. METHODS: 38 patients with histologically proven malignant melanoma (tumor thickness > 0.75 mm) were preoperatively examined by injecting 40 MBq 99mTc-Nanocoll intradermally around the lesion. The first lymph node identified was marked on the skin. Immediately after scintigraphy patients were referred to the operation room and intraoperatively mapped using a handheld gamma probe. Activity of the SLN and of the adjacent nodes was measured ex vivo. After excision of the SLN, the lymphatic basin was re-checked for radioactivity and activity of the SLN and of the adjacent nodes was re-measured after removal. RESULTS: The hottest reading was found in all patients in vivo and ex vivo in the preoperatively marked lymph node. Morphologically (macroscopically, ultrasound, CT) all nodes were unsuspicious. Histologically, in 8 patients metastatic involvement of the lymph node was found which led to a wide exploration of the lymphatic basin with consecutive lymph node excision in 7 patients. CONCLUSION: The findings suggest that combined preoperative lymphoscintigraphy and intraoperative mapping with a gamma probe is a powerful approach for exact localization of the SLN. Diagnostic detection of the SLN may have considerable impact for patient management, since extended lymph node dissection may be confined to patients presenting with positive SLN.

Adult↗
PubMed1997

Partial restoration of scintigraphically assessed cardiac sympathetic denervation in newly diagnosed patients with insulin-dependent (type 1) diabetes mellitus at one-year follow-up.

Diabetic neuropathy is thought to comprise a reversible metabolic and an irreversible structural component of neuronal abnormality. To investigate whether the cardiac sympathetic denervation recently described in newly diagnosed, but metabolically stabilized, diabetic patients without myocardial perfusion abnormalities reflects transient or permanent sympathetic abnormalities, 123-I-metaiodobenzylguanidine (123-I-MIBG) scintigraphy was performed in 16 patients with insulin-dependent (Type 1) diabetes mellitus (IDDM) 1 year after initial assessment and diagnosis. All patients had been treated with an intensified insulin therapy for 1 year. HbA1c had fallen from 11.5 +/- 2.0% to 6.3 +/- 0.9% (p < 0.001). The global myocardial 123-I-MIBG uptake (score 1-6) had improved in 7 patients at 1 year, remained unchanged in 7, and deteriorated in 2 patients. Regionally, the myocardial uptake score of the posterior and septal regions had improved significantly (p < 0.01, p = 0.02) with a mean uptake score in the groups of 3.8 +/- 1.1 and 3.4 +/- 1.2 at diagnosis versus 2.6 +/- 0.5 and 2.5 +/- 0.9 at 1 year. Myocardial uptake scores of the anterior, lateral, and apical regions had also improved in 7, 6, and 9 patients, but the mean changes of these scores did not reach significance. The study demonstrates that scintigraphically assessed cardiac sympathetic denervation in newly diagnosed, but metabolically stabilized, IDDM patients is partially reversed with improved metabolic control after 1 year of intensified insulin therapy. We suggest that even in the early stage of IDDM, cardiac sympathetic dysfunction is composed of reversible and irreversible neuronal abnormalities.

3-Iodobenzylguanidine↗
PubMed1997

Detection of hepatocellular carcinoma with a new alpha-fetoprotein antibody imaging kit.

PURPOSE: The aim of this phase II study was to assess the clinical utility and safety of AFP-Scan (Immunomedics, Inc, Morris Plains, NJ), a technetium-99m (99mTc)-labeled anti-alpha-fetoprotein (AFP) Fab' imaging kit, in the evaluation of hepatocellular carcinoma (HCC), in comparison to computed tomography (CT). PATIENTS AND METHODS: Twenty-five consecutive patients with a history of HCC were examined by planar and single-photon emission computed tomography (SPECT) imaging at 6 and 24 hours after intravenous (I.V.) injection of 1 mg AFP-Scan labeled with 925 MBq 99mTc. RESULTS: In 20 patients, there was a specific binding of the Fab' antibody to the tumor, whereas in four patients who presented with elevated serum AFP levels, no specific targeting was found and no malignant lesions were evident by CT or biopsy. One patient was diagnosed as false-negative by AFP-Scan. In five of six patients with normal serum AFP levels, focal uptake was demonstrated. In one case, metastatic disease in the lower abdomen was found. In all patients, diagnostically relevant information was provided by the 24-hour antibody images, especially with SPECT. Comparing AFP-Scan versus CT, the former showed a higher sensitivity (95% v 63%) and specificity (67% v 17%), with an overall accuracy of 88% versus 52% for AFP-Scan versus CT, even in patients with normal serum AFP titers. No adverse reactions or human antimouse antibody (HAMA) elevations were found in any of the patients. CONCLUSIONS: AFP-Scan appears to be a promising new antibody imaging kit for the disclosure of sites of HCC and should aid in the management of these patients by revealing primary, recurrent, and metastatic disease with a single imaging modality.

Adult↗
PubMed1996

Autoantibodies against sympathetic ganglia and evidence of cardiac sympathetic dysinnervation in newly diagnosed and long-term IDDM patients.

To investigate the presence of autoantibodies against sympathetic nervous tissue and their correlation with cardiac sympathetic dysinnervation in insulin-dependent diabetes mellitus (IDDM), 20 newly diagnosed (age 26 +/- 6 years) and 48 long-term IDDM patients (age 40 +/- 13 years, duration of diabetes 22 +/- 12 years) without myocardial perfusion abnormalities (normal 99mTC-methoxyisobutylisonitrile uptake) were assessed for myocardial 123I-metaiodo benzylguanidine (123I-MIBG) uptake and complement-fixing sympathetic ganglia (CF-SG) autoantibodies. Both groups of patients were also studied for islet cell antibodies (ICA) and ECG-based cardiac autonomic neuropathy. Eighty control subjects (age 18-49 years) were investigated for CF-SG autoantibodies. Eight newly diagnosed (40%) and 12 long-term (25%) IDDM patients exhibited CF-SG autoantibodies, compared to 4 control subjects (5%; p < 0.01, p < 0.05). In long-term diabetic patients, the reduction of global but not of regional myocardial 123I-MIBG uptake correlated with CF-SG autoantibodies (r = 0.34, p = 0.02). Newly diagnosed diabetic patients did not show an association between CF-SG autoantibodies and global or regional myocardial 123I-MIBG uptake. ECG-based cardiac autonomic neuropathy (> or = two of five cardiac reflex tests abnormal) was present in 22 and absent in 26 long-term IDDM patients, of whom 9 (41%) and 3 (12%), respectively were positive for CF-SG autoantibodies (p = 0.02). Only 1 newly diagnosed IDDM patient demonstrated ECG-based cardiac autonomic neuropathy and was also positive for CF-SG autoantibodies. Although they are somewhat suggestive, results concerning autoantibodies against sympathetic nervous tissue and cardiac sympathetic dysinnervation do not strongly support the view that autoimmune mechanisms play a major role in the pathogenesis of cardiac sympathetic neuropathy in IDDM.

3-Iodobenzylguanidine↗
PubMed1996

Reduced myocardial 123I-metaiodobenzylguanidine uptake in newly diagnosed IDDM patients.

123I-labeled metaiodobenzylguanidine (123I-MIBG) scintigraphy is a novel technique for the assessment of cardiac sympathetic dysinnervation. To evaluate defects of the cardiac autonomic nervous system at the onset of IDDM, this technique together with conventional electrocardiogram (ECG)-based cardiac reflex tests and measurement of the QT interval was applied to 22 newly diagnosed metabolically stabilized IDDM patients without myocardial perfusion abnormalities (99mTc-labeled methoxyisobutylisonitrile scintigraphy) and 9 matched control subjects. Seventeen diabetic patients (77%), but none of the control subjects, were observed to have a reduced global myocardial uptake of 123I-MIBG. In contrast, only two diabetic patients (9%) demonstrated an ECG-based cardiac autonomic neuropathy (two or more of five age-related cardiac reflex tests abnormal) (P < 0.001). In newly diagnosed IDDM patients, the uptake of 123I-MIBG was reduced more in the posterior myocardial region compared with the lateral and apical region (P < 0.01, P = 0.03). The septal myocardial region exhibited a smaller uptake than the lateral myocardial region (P = 0.02). The maximum/minimum 30:15 ratio correlated with the global, anterior, lateral, and septal myocardial uptake of 123I-MIBG (P < 0.05, P < 0.05, P < 0.01, P < 0.05). A correlation between global and regional myocardial 123I-MIBG uptake and HbA1c or QT interval was not observed. Newly diagnosed metabolically stabilized IDDM patients without myocardial perfusion defects show evidence of cardiac sympathetic dysinnervation, as indicated by a reduction of 123I-MIBG uptake, at a significant higher proportion than ECG-based cardiac autonomic neuropathy. Furthermore, they present with regional differences of myocardial 123I-MIBG uptake.

3-Iodobenzylguanidine↗
PubMed1996

[111IN-octreotide and 123I-MIBG scintigraphy in the diagnosis of small intestinal carcinoid tumors--results of a comparative investigation].

AIM: This study compares the diagnostic value of 111In-Octreotide- and 123I-MIBG scintigraphy in the diagnostic imaging of carcinoids and correlates the results with CT findings. METHODS: Twenty-eight patients underwent octreotide-, MIBG scintigraphy and CT examination within a short time period. RESULTS: In 13/15 preoperatively examined patients somatostatin receptor expression of the tumor was demonstrated; MIBG-uptake was found in 8/15 cases. Octreotide and MIBG scintigraphy revealed liver metastases in 26 and 19 cases, respectively. CT-examinations detected liver metastases in 22 cases. The number of metastatic lesions found by MIBG and CT was lower than with octreotide. In 3 patients unknown mediastinal lesions were detected by the octreotide scan, 2/3 did not show MIBG uptake. In 5 non-hormone secreting tumors shown by octreotide scintigraphy, no MIBG uptake was found. With respect to the diagnostic accuracy octreotide scintigraphy appeared superior to MIBG. CONCLUSION: MIBG scans do not provide additional diagnostic information compared to octreotide scintigraphy. MIBG scintigraphy may be potentially useful in terms of planning 131I-MIBG therapy only.

3-Iodobenzylguanidine↗
PubMed1995

Diagnostic approach in acute pulmonary embolism: perfusion scintigraphy versus spiral computed tomography.

For diagnosing acute pulmonary embolism, perfusion scintigraphy in combination with ventilation studies is a well-established and sensitive method. Recently, computed tomography (CT) incorporating an angiographic technique was introduced for evaluating the pulmonary arterial system without breathing artefacts. The present study compared lung scans with spiral CT data to establish the diagnostic value of the latter approach. Twenty-five patients with a clinical suspicion of acute pulmonary embolism were examined using both methods. Perfusion and ventilation lung scans were done and spiral volumetric CT studies were performed. In 18 patients, pulmonary embolism was diagnosed using both methods. However, the results were interpreted differently. Particularly when centrally localized emboli were present in both pulmonary arteries, assessment of the more affected side was difficult on CT and depended on the experience of the physicians interpreting the scans. Small, (sub-)segmental emboli could not be demonstrated on CT. This may explain the false-positive and false-negative results, respectively. Spiral CT enables an exact demonstration of thrombosis in severe, centrally localized emboli. In incompletely occluded vessels, estimation of the degree and the location of perfusion defects is better with scintigraphy. Based on the present results and the technical equipment necessary for spiral CT, it is concluded that perfusion scintigraphy remains the method of choice for diagnosing acute pulmonary emboli.

Acute Disease↗
PubMed1993

MR imaging with Gd-DTPA in lesions of the head and neck.

The diagnostic value of MR in the head and neck with special emphasis on the contrast medium Gd-DTPA will be demonstrated. A total of 1,260 patients underwent MR with different pulse sequences plain and with Gd-DTPA. The sequences were analyzed and compared with CT. Due to the different pattern of enhancement the contrast medium helped in differentiating malignant and benign tumors from other processes like cysts and inflammatory changes. Except lesions with small bony erosion and inflammatory changes of the salivary glands MR with Gd-DTPA proved to be diagnostically advantageous in all cases. Gd-DTPA improved the delineation of tumor margins. MR in combination with Gd-DTPA offers a lot of new advantages for diagnosing lesions of the head and neck. However, due to the prolonged examination time and the lack of noninvasiveness the use of Gd-DTPA has to be considered critical for every single area of the head and neck.

Blood Vessels↗
PubMed1992

[The diagnostic value of nuclear magnetic resonance tomography in Sjögen's disease].

Sjögren's syndrome is characterised by xerostomia, xerophthalmia and recurrent parotid swelling. There is a high coincidence with rheumatoid diseases. A variety of clinical and laboratory parameters offers important information for diagnosis, but none of them is specific for this disease. 36 patients with clinical diagnosis of Sjögren's syndrome were examined in a prospective study to evaluate the diagnostic significance of this technique. 34 patients showed an inhomogeneous, nodular pattern in the parotid gland. The signal intensity was very high, especially in the T2-weighted sequences. There was a significant correlation of the radiologic changes with the course of the disease. Four patients with the clinical diagnosis of sialadenosis demonstrated bilateral enlarged glands with a homogeneous signal pattern. Patients with acute purulent parotitis demonstrated enlargement of the gland without an alteration in the signal pattern. Patients with chronic recurrent parotitis and patients with radiogenic sialadenitis showed little inhomogeneous increase of signal intensity. Our results indicate that MRI is presently the radiological method of choice in the evaluation of Sjögren's syndrome.

Abscess↗
PubMed1991

MRI in tracheal stenosis by innominate artery in children.

Pediatric airway obstruction due to anomalies of the course of the innominate artery may produce respiratory distress. MR imaging of the trachea was performed after bronchoscopy on forty-one children with congenital tracheal stenosis. Bronchoscopy only allows the evaluation of the lumen of the trachea, and the degree and location of collapse, and it may be difficult to determine the etiology of the tracheal narrowing. In eighteen out of the forty-one patients MR imaging showed a compression of the trachea by the innominate artery. The MR imaging diagnoses were subsequently compared for accuracy with the diagnoses determined by direct surgical observations. MR imaging of the trachea, the surrounding tissue and vessels allows the evaluation of the cause of tracheal compression and the degree and location of collapse. For evaluation of the cause of airway obstruction. MRI is an ideal method depicting detailed anatomic structure without employing ionizing radiation or intravenous contrast medium.

Brachiocephalic Trunk↗
PubMed1991

[Magnetic resonance tomography of the oropharynx and oral cavity with Gd-DTPA. An optimized study technic and its diagnostic value].

In the evaluation of space-occupying lesions of the oropharynx it is necessary to perform modern imaging methods, such as magnetic resonance imaging additionally to clinical and endoscopical methods. 126 patients were examined using T1-weighted (TR = 500 ms, TE = 25 ms) and T2-weighted (TR = 3000 ms, TE = 25/90 ms) spin-echo-sequences before and after i.v. application of Gd-DTPA. Superficially growing lesions of stage T1 could not be delineated from isointense mucosa. The preoperative staging of T2-T4 lesions can be markedly improved by using T1- and T2-weighted sequences in combination with Gd-DTPA. MR imaging with Gd-DTPA is recommended as the primary diagnostic tool for diagnosing lesions in the region of the oropharynx.

Adenoma↗