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D L Munz

Publications and source records attributed to D L Munz.

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

Combined thallium-201 and dynamic iodine-123 iodophenylpentadecanoic acid single-photon emission computed tomography in patients after acute myocardial infarction with effective reperfusion.

BACKGROUND: Considerable derangements of energy metabolism are to be expected during ischemia and reperfusion. In ischemic myocardium, the oxidative degradation of carbohydrates is shifted toward the anaerobic production of lactate and the oxidation of fatty acids is suppressed. HYPOTHESIS: The aim of this study was to examine the uptake and metabolism of iodine-123 (123I) iodophenylpentadecanoic acid (IPPA) in stunned myocardium. METHODS: In 15 patients, SPECT with 201Tl and 123I IPPA as well as echocardiography with low-dose dobutamine stimulation were performed 12 +/- 5 days after myocardial infarction with reperfusion. Follow-up echocardiography was carried out 24 +/- 8 days later for documentation of functional improvement. Uptake of 201Tl and 123I IPPA were obtained in five left ventricular segments, and dynamic SPECT imaging was used for calculation of the fast and the slow components of the biexponential myocardial 123I IPPA clearance. RESULTS: Wall motion improved in 14 of 26 dysfunctional segments (54%). Stunned segments were characterized by a reduced 123I IPPA extraction, a shorter half-life of the fast, and a longer half-life of the slow clearance component. All parameters of the combined 201Tl/123I IPPA study predicted functional recovery with similar accuracies (area under the receiver operator characteristic curves between 0.68 and 0.76; p = NS). Analysis of 201Tl uptake alone could not predict functional recovery in this study. CONCLUSIONS: Stunned myocardium is characterized by a disturbance of fatty acid metabolism. For prediction of functional improvement, 123I IPPA imaging added significant diagnostic information.

Adult↗
PubMed2000

Recovery correction for quantitation in emission tomography: a feasibility study.

In emission tomography, the spread of regional tracer uptake to surrounding areas caused by limited spatial resolution of the tomograph must be taken into account when quantitating activity concentrations in vivo. Assuming linearity and stationarity, the relationship between imaged activity concentration and true activity concentration is only dependent on the geometric relationship between the limited spatial resolution of the tomograph in all three dimensions and the three-dimensional size and shape of the object. In particular it is independent of the type of object studied. This concept is characterized by the term "recovery coefficient". Recovery effects can be corrected for by recovery coefficients determined in a calibration measurement for lesions of simple geometrical shape. This method works on anatomical structures that can be approximated to simple geometrical objects. The aim of this study was to investigate whether recovery correction of appropriate structures is feasible in a clinical setting. Measurements were done on a positron emission tomography (PET) scanner in the 2D and 3D acquisition mode and on an analogue and digital single-photon emission tomography (SPET) system using commercially available software for image reconstruction and correction of absorption and scatter effects. The results of hot spot and cold spot phantom measurements were compared to validate the assumed conditions of linearity and stationarity. It can be concluded that a recovery correction is feasible for PET scanners down to lesions measuring about 1.5xFWHM in size, whereas with simple correction schemes, which are widely available, an object-independent recovery correction for SPET cannot be performed. This result can be attributed to imperfections in the commercially available methods for attenuation and scatter correction in SPET, which are only approximate.

Feasibility Studies↗
PubMed2000

Regional cerebral glucose metabolism in healthy volunteers determined by fluordeoxyglucose positron emission tomography: appearance and variance in the transaxial, coronal, and sagittal planes.

PURPOSE: In this study, the contribution of the transaxial, coronal, and sagittal planes in evaluations of regional cerebral glucose metabolism was investigated in healthy volunteers as determined by fluorine-18-labeled 2-deoxy-2-fluoro-D-glucose (FDG) and high-resolution positron emission tomography (PET). METHODS: One hundred twenty-seven healthy right-handed volunteers were injected with 4.2 MBq/kg (0.11 mCi) body weight FDG and imaged in a PENN PET H 240 scanner. Images were corrected for scatter and random coincidences and reconstructed in all three planes into 6- to 8-mm-thick slices. The reconstructed images were corrected for attenuation using the Chang algorithm. The transverse, coronal, and sagittal images were read independently of each other using a qualitative scale in which 1 = equal to, 2 = mildly, 3 = moderately, and 4 = markedly less than the area with the highest glucose metabolism in the respective plane. RESULTS: The areas with the highest glucose metabolisms were the posterior cingulate gyri with mean scores of 1.1 to 1.2, thalami (1.2 to 1.3), basal ganglia (1.5 to 1.9), and visual cortex (1.6). The lowest values were found in the occipital cortex (2.7 to 2.8) and the cerebellum (2.3 to 2.4). Whereas reliable analysis of the mesial temporal aspects was not feasible in the sagittal plane, the anterior poles of the temporal and frontal lobes could not be evaluated in the coronal or the inferior temporal areas in the transaxial slices. In all three planes, regional glucose metabolism was less in the lateral temporal areas on the left than on the right (P < 0.001). The consistency of readings as measured in terms of coefficients of variation was greatest in the coronal plane for the caudates and posterior cingulate gyri, in the transaxial plane for the lateral temporal regions, and in the sagittal plane for the visual cortex. Age-dependent decreases in regional glucose metabolism in the inferior and lateral frontal regions and the parietal lobes were found in all three planes. CONCLUSIONS: All three projection planes must be used for a comprehensive qualitative evaluation of the regional glucose metabolism of the brain.

Adult↗
PubMed2000

Classification of the lymphatic drainage status of a primary tumour: a proposal.

AIM: Creation of a classification of the lymphatic drainage status of a primary tumour. It shall enable comparison of different approaches, standardization and quality control. METHODS: Identification and topographic localization of the sentinel node(s) using lymphatic radionuclide gamma camera imaging and/or gamma probe detection and/or vital dye mapping. RESULTS: A classification comprising four classes (D-Class I-IV) and distinct subclasses (A-E) proved to be simply to be learned and applicable as well as reliably reproducible. It is based on the number of sentinel lymph nodes and their locations and can be combined with the pathological and molecular biological lymph node status. D-classes/subclasses obtained in 420 patients with malignant melanoma of the skin are presented. CONCLUSIONS: The classification is applicable to different approaches. Its diagnostic, therapeutic and prognostic value should be studied prospectively in those primary tumours which preferably metastasis via their draining lymphatic vessels.

Documentation↗
PubMed1999

Nuclear medicine imaging of endocarditis.

Infective endocarditis is a serious disease which requires early diagnosis and adequate therapy. Echocardiography plays a key role in diagnosis and follow-up. Subacute infective endocarditis, however, is often difficult to prove echocardiographically due to its more subtle morphological changes. Also, echocardiography cannot reliably differentiate florid vegetations from residual structural changes of the affected valves in cured patients. Therefore, scintigraphy of infection and inflammation, a functional imaging procedure, has been investigated as a complementary tool in diagnosis and follow-up of infective endocarditis. So far, results obtained with Gallium-67 scintigraphy are not convincing, although an improvement by using modern acquisition techniques seems possible. Scintigraphy with Indium-111 labelled leukocytes has an unacceptably low sensitivity, which is probably due to the small number of cells involved and unfavourable imaging characteristics of 111In-Technetium-99m labelled leukocytes have been investigated in few patients, so final judgement is not yet possible. SPECT imaging might enhance the detectability of diseased heart valves. Immunoscintigraphy with the 99mTc labelled antigranulocyte antibody in SPECT technique is complementary to echocardiography and seems to assess the floridity of the underlying inflammatory process. The combined use of both imaging modalities allows detection of virtually all cases of subacute infective endocarditis. SPECT immunoscintigraphy with the antigranulocyte antibody seems useful in doubtful cases of infective endocarditis, especially, if echocardiography is non-diagnostic and valve pathology pre-existing. The method may be used for follow-up and monitoring antibiotic therapy.

Antibodies, Monoclonal↗
PubMed1998

Changes in perfusion pattern using ECD-SPECT indicate frontal lobe and cerebellar involvement in exercise-induced paroxysmal dystonia.

The clinical features of exercise-induced paroxysmal dystonia (EPD) are delineated in a pedigree including two affected members (both male) showing an autosomal-dominant inheritance trait. Gait analysis using kinematic electromyography during the motor attacks revealed coactivation of antagonistic calf muscles characteristic of dystonia. In the interval, impaired muscular alternation was observed. To characterize further the pathophysiological basis of the condition, ictal and interictal cerebral perfusion SPECT studies using technetium 99m-ethyl cysteinate dimer (ECD) were performed to establish whether cortical hyperactivity indicative of epilepsy is present during the motor attacks and to identify regional changes in the ictal perfusion pattern that could indicate an anatomic structure relevant to the disease. During the motor attacks, decreased ictal perfusion of the frontal cortex was found in both patients. In contrast, increased cerebellar perfusion was observed. The perfusion of the basal ganglia also decreased. No cortical hyperperfusion indicative of an epileptic nature was seen. Cerebellar hyperactivity in connection with prominent frontal hypoactivity has also been described in both the idiopathic and the symptomatic forms of dystonia. Our findings therefore suggest that EPD represents a paroxysmal movement disorder rather than epilepsy. It is concluded that changes in frontal and in cerebellar function are relevant to the pathophysiology of EPD.

Adolescent↗
PubMed1998

Somatostatin receptor scintigraphy in small-cell lung cancer: results of a multicenter study.

UNLABELLED: The aims of this study were to determine the accuracy of somatostatin receptor scintigraphy in the detection of the primary tumor and its metastases in small-cell lung cancer (SCLC) in a large patient population, and to investigate the course of somatostatin uptake in primary tumors during therapy. METHODS: In a total of 100 patients, 134 examinations were performed. Twenty-seven of the patients were examined before and after chemotherapy. Planar whole-body images were acquired 4 hr and 24 hr after injection of approximately 200 MBq (111)In-pentetreotide. SPECT of the thorax was performed after 24 hr. Tumor-to-background (T/B) ratios for the primary tumor were averaged from anterior and posterior projections. RESULTS: Compared to conventional investigations, somatostatin receptor scintigraphy (SRS) visualized the primary tumor with varying degrees of uptake in 96% of the examinations. Regional metastases and distant metastases were detected in 60% and 45% of the examinations, respectively. The uptake of the somatostatin analog by the primary tumor was significantly lower in the patients examined during chemotherapy as compared to those examined before treatment (T/B ratio = 1.94+/-0.79 versus 2.35+/-0.9, p < 0.005). A decrease in T/B ratio was noted in patients with remission at the time of SRS (from 2.40+/-1.56 to 1.63+/-0.72, p < 0.05). No difference in the pretreatment uptake of octreotide by the primary tumor was identified between patients with tumor progression and those with partial or complete remission. CONCLUSION: Somatostatin receptor scintigraphy has a high sensitivity in the detection of the primary tumor in SCLC but fails in the detection of metastases. Thus, SRS does not provide useful information for staging of SCLC. Since somatostatin uptake by the primary tumor is affected by chemotherapy, it may be used to follow up on the course of SCLC.

Adult↗
PubMed1998

[Septal myocardial perfusion in complete left bundle branch block: case report and review of the literature].

Myocardial scintigraphy was performed three times in a 55-year-old woman with left bundle branch block (LBBB). A significant LAD stenosis had been excluded by coronary angiography. The first scintigraphy was performed with Tc-99m sestamibi after submaximal bicycle exercise and revealed a septal perfusion deficit. This deficit could not be reproduced in the following examinations after pharmacological stress testing with dipyridamole using both Tl-201 and Tc-99m sestamibi. Perfusion at rest assessed with Tl-201 was normal in all studies. It is concluded that pharmacological stress testing with dipyridamole is to be preferred in patients with LBBB. With respect to the accuracy of myocardial perfusion imaging the choice of the radiopharmaceutical plays a less important role.

Bundle-Branch Block↗
PubMed1998

Clinical value of immunoscintigraphy in patients with fever of unknown origin.

UNLABELLED: The aim of our study was to evaluate the clinical value of immunoscintigraphy with the monoclonal antibody 99mTc-BW 250/183 in patients with fever of unknown origin (FUO). The antibody BW 250/183 is an immunoglobulin G1 subtype that binds to the antigen NCA-95, which is expressed on the cell membrane surface of granulocytes. METHODS: We studied 51 patients who were referred with the diagnosis of FUO. Thirty-five percent of the patients suffered from infection, 17% had autoimmune diseases, 14% had neoplasms and 8% had other diseases. The remaining 28% of the patients did not have a diagnosis. Planar imaging was performed in all patients, and 19 patients underwent SPECT. In our analysis, both cold and hot spots were considered diagnostic. RESULTS: Pyogenic infections were visualized correctly in 13 foci. The diagnosis of endocarditis (n = 4) could be determined only by SPECT. False-negative results were found in 4 patients and false-positive uptake was seen in 2 patients. No false-positive uptake or cold spots in the central bone marrow were found in patients with viral, granulomatous and autoimmune diseases or in those patients in whom no FUO cause was found in a 6-mo follow-up. In these patients, a negative scan did not change their diagnostic work-up. Cold spots in the central bone marrow were correctly interpreted in 5 of 6 patients. Sensitivity in detecting pyogenic foci was 73% and specificity was 97%. Positive and negative predictive values were 93% and 87%, respectively. Including areas of decreased uptake in the analysis, sensitivity for detecting an underlying inflammatory or malignant process for FUO was 81 % and specificity was 87%. Positive and negative predictive values were 81% and 87%, respectively. CONCLUSION: Immunoscintigraphy with 99mTc-BW 250/183 in patients with FUO has clinical potential for the diagnosis and exclusion of pyogenic causes of FUO. Metastatic malignant disease and high-grade spondylodiskitis could be diagnosed early in a diagnostic work-up by a characteristic cold spot pattern in the bone marrow. SPECT is indispensible for scintigraphic imaging of endocarditis.

Adult↗
PubMed1998

Scintigraphic localization of lymphatic leakage site after oral administration of iodine-123-IPPA.

UNLABELLED: Chylothorax can occur secondary to traumatic lesions of the thoracic duct caused by chest injuries, surgical procedures involving the pleural space, neoplasms or malformations of the lymphatics. METHODS: Lymphatic leakage sites were localized by scintigraphy after oral administration of the 123I-labeled long-chain fatty acid derivative iodophenyl pentadecanoic acid (IPPA). We report on three patients with different lymphatic leakage sites and on one normal control subject. RESULTS: IPPA scintigraphy localized the lymphatic leakage site correctly in all three patients. In two of them, the method even guided the successful surgical treatment of the leakage. CONCLUSION: This approach is suitable for detecting lymphatic leakages of intestinal origin.

Administration, Oral↗
PubMed1997

Anti-carcinoembryonic antigen antibodies versus somatostatin analogs in the detection of metastatic medullary thyroid carcinoma: are carcinoembryonic antigen and somatostatin receptor expression prognostic factors?

BACKGROUND: Surgery is currently the only potentially curative approach in the treatment of medullary thyroid carcinoma (MTC). In many instances however, postsurgically elevated or rising plasma calcitonin and/or carcinoembryonic antigen (CEA) levels indicate persistent metastatic disease, although conventional diagnostic procedures (computed tomography (CT), magnetic resonance imaging (MRI), and invasive venous catheterization) fail to localize the responsible lesions. Recently, anti-CEA antibodies and somatostatin analogs have shown promising results in the staging of MTC. The aim of this study was to compare the sensitivity of both methodologies, especially for the detection of occult MTC, and to assess whether there may be correlations between the scintigraphic behavior and the patients' prognosis. METHODS: A total of 26 patients with medullary thyroid carcinoma were examined at our institution between 1977 and 1996. Ten of them had known disease, 14 had occult metastatic MTC, and 2 were free of disease at the time of presentation. Fourteen patients were investigated with anti-CEA monoclonal antibodies (MAbs) (receiving a total of 35 injections: clones BW431/26, BW431/31, IMACIS, or F023C5, labeled with 99mTc, (111)In or (131)I), and 8 patients were studied with (111)In-labeled octreotide. Two patients received potentially therapeutic doses of (131)I-labeled anti-CEA antibodies. All patients underwent conventional radiologic evaluation (ultrasonography, CT, and MRI) and/or biopsy within 4 weeks. Additional imaging was performed with 99mTc-(V)-DMSA, (131)I-metaiodobenzylguanidine, 201thallium chloride, 99mTc-methylene diphosphate, and/or 18F-fluorodeoxyglucose-positron emission tomography. Clinical follow-up was obtained. RESULTS: All patients with established disease had elevated plasma CEA (range, 6.8-345 ng/mL; calcitonin levels between 92 and 11,497 pg/mL), whereas in 9 of 14 occult cases, levels were < or = 5 ng/mL (range, 0.6-829 ng/mL; calcitonin, 72-2920 pg/mL). In patients with known disease, the overall lesion-based sensitivity was 86% for the anti-CEA MAbs, whereas octreotide was unable to target any tumor in patients with rapidly progressing disease or distant metastases (overall sensitivity, 47%). In all patients with occult MTC, anti-CEA MAbs and octreotide were able to localize at least one lesion (patient-based sensitivity, virtually 100%). In patients with postsurgically persistent hypercalcitoninemia, cervical lymph nodes were identified as the most frequent site of metastases, whereas in patients with occult and slowly progressing disease several years after primary surgery, anti-CEA MAbs and octreotide showed bilateral involvement of mediastinal lymph nodes; however, tumor to nontumor ratios were usually higher with octreotide in these cases. With anti-CEA Mabs, the highest tumor to nontumor ratios were observed in clinically aggressive, rapidly progressing disease. The sensitivity of all other diagnostic modalities was, at < or = 50%, significantly lower. Indication for antitumor effects was observed in a patient receiving 65 mCi of (111)I-labeled F(ab')2 fragments of the clone F023C5. CONCLUSIONS: For the detection of occult MTC, anti-CEA MAbs and octreotide seem to have a sensitivity that is superior to conventional diagnostic modalities, especially also when used in combination. Better detectability with anti-CEA antibodies (which may result in higher CEA expression) seems to be associated with more aggressively growing forms of MTC, whereas somatostatin receptor expression at normal CEA plasma levels and weaker MAb targeting may be associated with a more benign clinical course. This is in accordance with the study of Busnardo et al. (Cancer 1984; 53:278-85), who showed higher CEA serum levels to be associated with a worse prognosis, as well as with the in vitro findings of Reubi et al. (Lab Invest 1991;64:567-73), who demonstrated lower somatostatin receptor expression in less differentiated MTC. Fu

Adult↗
PubMed1997

Somatostatin receptor scintigraphy in the staging of lymphomas.

In this prospective study we evaluated the somatostatin receptor scintigraphy in the initial staging of 19 patients suffering from Hodgkin's (HD) and non-Hodgkin's lymphomas (NHL) and in the restaging of 16 patients. Scintigraphy was compared to the results of the methods applied for adequate staging of lymphoma patients in the large multicentre trials. Planar imaging and SPECT was performed after intravenous injection of 110 or 220 MBq of 111In-pentetreotide. The patient-based analysis yielded an overall sensitivity of 88%, contrasting lesion-based sensitivities of 57%, 35%, and 43% in HD, low-grade NHL and high-grade NHL, respectively. The best results were obtained in the head-and-neck region and the worst in the abdomen (sensitivities of 61% and 24%, respectively). Bone marrow infiltration was visible in 1/12 cases only. There was no significant difference between the outcomes of patients in the initial staging and restaging and no influence of the amount of injected radiopharmaceutical on the results. In terms of the Ann-Arbor classification, 10/35 patients were concordant whereas 22 were understaged and 3 overstaged scintigraphically. In conclusion, somatostatin receptor scintigraphy is not useful in the initial staging or restaging of malignant lymphomas, especially NHL, due to low lesion detection rates most probably because of low receptor densities. In addition, intraindividual heterogeneity of somatostatin receptor expression has to be considered.

Adult↗
PubMed1997

Immunoscintigraphy of the bone marrow: normal uptake values of technetium-99m-labeled monoclonal antigranulocyte antibodies.

UNLABELLED: The aim of our study was to determine the normal range of the 99mTc-labeled anti-NCA 95 antigranulocyte antibody (AGAb) uptake in the bone marrow using the sacroiliac-to-background uptake ratio in the posterior view. METHODS: We made 169 planar bone marrow scans on 162 patients who were each injected with 555 MBq AGAb. Fifty patients with the diagnosis of infection/pyrexia of unknown origin (PUO) and with completely normal bone marrow scintigraphy were defined as the normal group. Uptake ratios were calculated drawing irregular regions of interest around the sacroiliac and a background area, respectively. RESULTS: The normal group revealed a mean uptake ratio of 7.3 +/- 2.3 (range 4.4-12.6). Similar uptake ratios were obtained in patients with the primary diagnosis of infection/PUO and bone marrow extension (7.4 +/- 2.2, range 4.2-11.7), suggesting that the bone marrow reacts on infection primarily by extension into the periphery, without any significant increase of the activity of the central hemopoietic/granulopoietic bone marrow. Mean uptake ratios also were not significantly different in patients with normal bone marrow scintigraphy and the primary diagnosis of solid malignant tumors, lymphomas and plasmacytomas, and in patients with focal lesions visible on bone marrow scintigraphy (soft tissue inflammation or cold lesions in the bone marrow but with normal sacroiliac regions). Mean uptake ratios in the normal group were significantly age related, amounting to 8.5 +/- 1.8, 7.5 +/- 1.9 and 6.1 +/- 2.0 in patients younger than 40 yr, between 40 and 59 yr, and 60 yr or older, respectively (p = 0.0025). The method revealed good inter- and intraobserver agreement with correlation coefficients of about r = 0.90 and r = 0.95, respectively. Inter- and intraobserver coefficients of variation were 6.6% and 4.6%, respectively. CONCLUSION: Determination of the bone marrow uptake ratio is simple and reproducible. The normal values established in this study were age dependent, which has to be considered when interpreting bone marrow uptake ratios. The presence of infection/PUO, solid malignant tumors, lymphomas and plasmacytomas does not seem to alter the AGAb uptake ratio significantly. The most important application of the quantitative analysis of bone marrow scintigraphy could be the diagnosis and follow-up of diseases with depression of the central hemopoietic activity.

Antibodies, Monoclonal↗