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A Staudenherz

Publications and source records attributed to A Staudenherz.

33 records · Page 2Linked to original sources
PubMed1997

The diagnostic value of planar and SPET scintimammography in different age groups.

Planar scintimammography (SMM) with 99Tcm-sestamibi (99Tcm-MIBI) has proved to be a useful method in the evaluation of breast lesions. The aim of our study was to determine the diagnostic value of planar and single photon emission tomograpic (SPET) SMM in different age group. We investigated women with breast lesions for which the surgeon recommended biopsy or careful follow-up. Seventy consecutive patients underwent supine planar SMM, while supine SPET was performed in 68 of the patients. Twenty-seven carcinomas in 23 patients and 35 benign lesions in 31 patients were confirmed histologically. In the remaining 16 patients, the findings were classified as benign at follow-up. The carcinomas and benign lesions had a mean (+/- S.D.) diameter of 25 +/- 17 and 17 +/- 11 mm respectively (P < 0.05). A sensitivity/specificity of 67/96% and 88/91% was obtained with the planar and SPET techniques respectively. The accuracy of both techniques was 90%. In patients aged 40 years or less, SPET increased the sensitivity from 50 to 100% (P < 0.01), whereas it decreased the specificity and accuracy from 94 to 81% and 91 to 81% respectively (N.S.). In patients aged 41-50 years, the sensitivity increased from 63 to 100% (P < 0.01), whereas there was a small decrease in specificity and an increase in accuracy (from 91 to 89% and 86 to 91% respectively, N.S.) We conclude that, in younger patients, a negative SPET SMM study indicates the need for careful follow-up rather than biopsy. However, the addition of SPET in supine scintimammography does-not change the overall accuracy significantly.

Adult↗
PubMed1997

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

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

Adult↗
PubMed1997

Differentiation of benign and malignant breast lesions: MR imaging versus Tc-99m sestamibi scintimammography.

PURPOSE: To compare the accuracies of magnetic resonance (MR) imaging and scintimammography in differentiating benign from malignant breast lesions. MATERIALS AND METHODS: MR imaging was performed in 66 women with 75 lesions during intravenous administration of gadopentetate dimeglumine. Planar and single photon emission computed tomographic (SPECT) scintimammography were performed (with 740 MBq technetium-99m sestamibi administered intravenously) in all 66 patients with 75 lesions and in 64 patients with 73 lesions, respectively. MR imaging and scintimammographic studies were independently evaluated by using signal intensity measurements versus time or focal tracer uptake to differentiate benign from malignant lesions. Histopathologic proof was obtained in 63 lesions. Twelve lesions were monitored with follow-up. RESULTS: MR imaging was false-negative in one and false-positive in nine lesions. Planar scintimammography was false-negative in 10 and false-positive in six lesions. SPECT scintimammography was false-negative in four and false-positive in 10 lesions. Sensitivities and specificities for malignancy were, respectively, 96% and 82% for MR imaging, 62% and 88% for planar scintimammography, and 83% and 80% for SPECT scintimammography. CONCLUSION: Both MR imaging and scintimammography are useful in the evaluation of breast cancer. MR imaging is more sensitive and as specific as scintimammography.

Adult↗
PubMed1996

Pattern recognition in five-phase bone scintigraphy: diagnostic patterns of reflex sympathetic dystrophy in adults.

The objective of this study was to assess qualitative and quantitative patterns of tracer accumulation to increase the diagnostic utility of bone scintigraphy in reflex sympathetic dystrophy (RSD). Of 120 patients with high clinical suspicion for RSD, 96 were confirmed as having RSD during follow-up, while the remaining 24 were used as controls. Clinical parameters were measured and correlated to five activity ratios (0-30 s, 0.5-5 min, 5-15 min, 3 h, 24 h) and five scintigraphic signs. Monitoring three dynamic phases revealed different tracer kinetics of potential diagnostic utility; however, the 24-h bone phase offered no additional diagnostic contribution and can be omitted. Quantification provided objective parameters for the duration of symptoms, pain and impairment of movement but not for surface temperature differences, swelling and impairment of physical force. It is of limited use for diagnosis except for the exclusion of disease. Discriminant analysis revealed the combination of three signs (diffuse uptake in carpus/tarsus+diffuse uptake in all small joints+increased activity ratio in the late blood pool phase) to be the pattern with the highest diagnostic accuracy independent of localisation, sex, age and precipitating factors. It is concluded that the scintigraphic confirmation of RSD is based on lateralisation in the late blood pool phase and the described pattern in the early bone phase.

Adult↗
PubMed1996

Utility of technetium-99m-sestamibi to assess osseous tumor spread.

We report the staging results and the surgical outcome of a male patient with squamous-cell carcinoma in the floor of the mouth and a bone SPECT scan suggestive of local tumor infiltration of the mandible. Additional 99mTc-sestamibi SPECT imaging of the primary tumor and superimposing of both studies excluded osseous tumor spread and less extensive surgery was performed. Pathohistological examination confirmed the scintigraphic results and indicated a nonspecific periostal reaction as the cause of the positive bone scan. Nevertheless, a high-resolution camera and careful superimposition of both studies is mandatory if the differential diagnosis of an osseous tumor spread of a malignant tumor in the floor of the mouth and possibly less extensive surgery is at stake.

Carcinoma, Squamous Cell↗
PubMed1996

Five phase bone scintigraphy supports the pathophysiological concept of a subclinical inflammatory process in reflex sympathetic dystrophy.

This study evaluates quantitative and qualitative patterns of bone scintigraphy and correlates them to laboratory findings and clinical signs to reveal possible inflammatory reactions in RSD. Activity ratios between the affected hand/foot and the contralateral side were calculated in 99mTc DPD-bone scintigraphy for five phases (arterial: 0-30 sec, early blood pool: 0.5-5 min. late blood pool: 5-15 min, 3 hrs early bone, 24 hrs late bone phase) and the presence of five scintigraphic signs in the bone phases was assessed. Activity ratios of all phases correlated with ESR those in the early and late bone phase correlated with alpha 2 globulin and beta globulin concentrations and those in the arterial, the early and late blood pool phase with the gamma globulin concentrations, respectively. Clinical features such as pain, swelling, physical force, temperature differences and the duration of symptoms did not correlate to the activity ratios. However, three signs in the bone phase were negatively correlated to albumin concentrations. Positive correlations were found for alpha 2, gamma globulin concentrations, ESR, neutrophil cell counts and individual uptake patterns. We conclude that the quantitative analysis of five phase bone scintigraphy in RSD reveals different aspects of tracer kinetics and provides different pathophysiological information. Lateralization of regional hyperemia, increased micro vascular permeability and bone metabolism in RSD parallels shifts in protein concentrations and blood cell counts that are suggestive of a subacute inflammatory process, even in patients with no overt signs of inflammation.

Beta-Globulins↗
PubMed1995

Three-phase bone scintigraphy of hydroxyapatite ocular implants.

Hydroxyapatite ocular implants are replicas of lamellar bone tissue derived from the exoskeleton of a reef-building coral by a hydrothermal chemical exchange reaction. Attached to the eye muscles, they act as a passive framework for fibrovascular ingrowth and can be drilled to hold the visible part of the artificial eye and allow synchronous eye movement. Fibrovascular ingrowth has to be confirmed by bone scintigraphy before the drilling procedure. This study monitored the vascular ingrowth into the implant in ten patients over 12 months to establish a clinically feasible imaging protocol. Tracer accumulation was monitored visually and quantitatively in dynamic and single-photon emission tomography (SPET) scans after the intravenous administration of 600 MBq of 99mTc-DPD. The implants showed no tracer accumulation in the arterial or blood pool phase. Accordingly, dynamic scintigraphy can be omitted from the imaging protocol. Delayed tracer accumulation appeared no earlier than 2 and no later than 6 months after surgery. Planar scintigraphy is not recommended as high-resolution SPET is necessary to separate the implant from the surrounding bone. We conclude that imaging can be confined to high-resolution SPET 3 h after tracer injection, no earlier than 3 months after surgery. The vascularized hydroxyapatite orbital implant is an important in vivo model for bone-seeking agents to study their uptake kinetics independently of any soft tissue and bone disease. Our results provide evidence that in normal bones the chemical absorption of 99mTc-DPD into the crystalline structure of hydroxyapatite is the only quantitatively relevant uptake mechanism.

Diphosphonates↗
PubMed1995

Parenchymal and nonparenchymal uptake of technetium-99m, indium-111, and iodine-125 low-density lipoprotein in the normal and estradiol-stimulated rat liver: tracer validation for quantitative low-density lipoprotein scintigraphy.

This study quantifies the parenchymal and nonparenchymal uptake of technetium-99m (99mTc)- and indium-111 (111In)-low-density lipoprotein (LDL) in different states of hepatic LDL-receptor activity to validate quantitative LDL scintigraphy. Iodine-125 (125I)-LDL was used as reference tracer. Four Sprague-Dawley rats with 17-alpha-ethinyl estradiol (EE)-stimulated LDL-receptor activity and five controls received all three tracers simultaneously 90 minutes before collagenase liver perfusion and metrizamide gradient cell separation. Total liver uptake of 99mTc-, 111In-, and 125I-LDL was 1.8 +/- 1.0, 1.6 +/- 0.8, and 0.2 +/- 0.2% injected dose/g organ weight, respectively. The contribution of nonparenchymal cells to total hepatic tracer uptake was 5.4 +/- 4.7%, 11.6 +/- 10.3%, and 9.6 +/- 7.6% in controls. Estradiol treatment increased total liver uptake to 2.4 +/- 0.5, 2.0 +/- 0.2, and 0.5 +/- 0.3% injected dose/g and reduced nonparenchymal cell contribution to 2.3 +/- 2.6%, 4.2 +/- 4.8%, and 2.6 +/- 2.9%, respectively. Dual-isotope scintigraphy in EE-treated and control rats confirmed these data, with a lower total hepatic uptake of 111In-LDL in comparison with 99mTc-LDL but a comparative degree of increase by EE treatment. Both behave quantitatively comparable as residualizing tracers, yet 99mTc-LDL shows a higher affinity to the LDL receptor pathway of parenchymal cells. However, the nonspecific uptake of both tracers can be neglected for quantitative LDL scintigraphy, and external imaging of hepatic tracer uptake primarily reflects LDL-receptor activity of parenchymal cells.

Animals↗
PubMed1995

[Satisfaction of paid thrombocyte donors with instrumental thrombocytapheresis].

OBJECTIVE: The increasing need for single-donor platelet concentrates makes it necessary to motivate platelet donors to donate regularly. The authors examined the contentment of existing donors in order to create a basis for improvements and to raise the attractiveness of donation. DESIGN: Open empirical data acquisition. SETTING: Institute for Transfusion Medicine at the General Hospital Vienna. PARTICIPANTS: 211 platelet donors. INTERVENTIONS: Interview with a self-developed questionnaire. RESULTS: Whereas donors rate the work of the staff as being very good, they are less content with the surroundings in the pheresis unit. Younger and higher-educated donors as well as persons who have been donating for less than 5 years show more negative ratings than comparable groups. The financial compensation is important to ensure a high donation frequency. CONCLUSIONS: The attractiveness of donation could be raised by improving certain aspects of donation. In order to ensure a high donation frequency donors should be granted a financial compensation, as otherwise particularly younger donors, who are more likely to be seronegative for antibodies to CMV, would not donate any more or at least not that often.

Adult↗
PubMed1995

Heterogeneity of myocardial perfusion provides the physiological basis of perfusable tissue index.

UNLABELLED: Assessment of viable from nonviable myocardium is critical for the care of patients being considered for revascularization procedures. Recently, the perfusable tissue index (PTI) has been proposed as an index of myocardial viability. METHODS: Computer simulations were performed for homogeneously and heterogeneously perfused tissue over a wide range of flows (0.04-6.4 ml/g/min) using both bolus and infusion inputs. RESULTS: PTI estimated from simulated homogeneously perfused tissue did reflect the amount of tissue being perfused independent of absolute level of flow, type of input or model configuration, whereas PTI obtained from simulated heterogeneously perfused tissue was consistently lower than the simulated "true" PTI and varied with flow, type of input function and model configuration. Flow estimated with 15O-water was not significantly different from that measured with radio labeled microspheres. CONCLUSION: Oxygen-15-water can diffuse into both acutely and chronically ischemic myocardium irrespective of its functional status. The results suggest that PTI is most likely an index of the heterogeneity of myocardial flow rather than an index of the amount of tissue being perfused. Its utility for delineating myocardial viability is thus related to the amount of tissue perfused that has low absolute levels of perfusion or high degrees of flow heterogeneity.

Analysis of Variance↗
PubMed1995

Scintigraphic pitfalls in giant parathyroid glands.

We report a case of hyperparathyroidism with surgically confirmed bilaterally enlarged parathyroid glands mimicking a normal thyroid gland. Technetium-99m-pertechnetate-201Tl chloride subtraction scintigraphy was inconclusive because of suppressed thyroidal [99mTc]pertechnetate uptake after coronary angiography. Technetium-99m-sestamibi double-phase scintigraphy showed homogeneous 99mTc-sestamibi uptake that mimicked a normal thyroid gland and no differential washout, thus leading to an erroneous visual interpretation of a normal scan. Semiquantitative assessment of tracer washout, however, can differentiate between normal thyroid tissue and symmetrical parathyroid uptake mimicking normal thyroid tissue. We conclude that semiquantitative assessment of tracer washout increases the diagnostic sensitivity of 99mTc-sestamibi double-phase scintigraphy if: (a) the interpreter is unaware of the anatomical situation, (b) the scintigraphic delineation of the thyroid is hampered by a blocked tracer uptake or (c) the visual interpretation reveals no differential washout in the neck region.

Aged↗
PubMed1994

Effectiveness of coronary heart disease risk management in high-risk patients.

The purpose of this study was to investigate the efficacy of the patient-based coronary heart disease (CHD) risk management strategy in general practice by analyzing patients who were sent to a specialized center as refractory to conventional treatment. Of the 452 patients studied, 152 were excluded because of secondary hyperlipidemia. The effects of a food protocol-monitored dietary/drug treatment on lipid profiles and CHD risk indices and the compliance to this approach were monitored for 12 months in 300 of 452 patients. CHD risk classification was performed according to NIH criteria by the referring physicians, but secondary hyperlipidemia was not identified and treated appropriately. Physicians did not fully utilize dietary and drug treatment and referred the patients to a specialized center too early. The initiated food protocol-controlled treatment was more efficient than pretreatment in general practice, with a compliance of 80.3% by patients selected according to their CHD risk. Long-term CHD risk reduction was persistent for 12 months in compliant patients; however, a cumulative dropout rate of 43% after 6 months and of 68% after 12 months was noted. Statistical analysis failed to reveal consistent prognostic factors of long-term compliance.

Apolipoproteins A↗
PubMed1993

Technetium-99m labelled LDL as a tracer for quantitative LDL scintigraphy. II. In vivo validation, LDL receptor-dependent and unspecific hepatic uptake and scintigraphic results.

The purpose of this study was to determine whether the hepatic uptake of dialysed technetium-99m labelled low-density lipoprotein (99mTc-LDL) reflects the hepatic LDL receptor activity and to what extent the non-LDL receptor-dependent 99mTc-LDL uptake by non-parenchymal cells relates to the diagnostic utility of quantitative 99mTc-LDL scintigraphy of the liver. New Zealand White rabbits and Watanabe Heritable Hyperlipidaemic rabbits, which were sacrificed 24 h after simultaneous injection of 99mTc-LDL and iodine-125 labelled LDL, were clearly discriminated by their hepatic 99mTc-LDL uptake according to their genetically different hepatic LDL receptor activity. Yet the hepatic 99mTc-LDL uptake exceeded the 125I-LDL uptake in all animals. The different hepatic uptake of the tracers was elucidated in the isolated perfused rat liver and was due to rapid intracellular degradation and the release of low molecular catabolites of 125I-LDL. In contrast, 99mTc activity was trapped in the liver. Analysis of biliary 99mTc activity provided evidence for the excretion of 99mTc-labelled apolipoprotein B. The amount of biliary excreted protein-bound 99mTc was linked to total hepatic 99mTc-LDL uptake and presumably reflected LDL receptor-mediated apolipoprotein excretion. Collagenase liver perfusion in Sprague-Dawley rats 90 min following simultaneous injection of 99mTc- and 125I-LDL and subsequent cell separation by gradient centrifugation revealed that 99mTc-LDL and 125I-LDL had a comparably low uptake into non-parenchymal cells; thus its contribution can be neglected for scintigraphic purposes. Planar scintigraphy was performed in New Zealand White and Watanabe Heritable Hyperlipidaemic rabbits.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗