Filters








2,375 Hits in 1.3 sec

Is hybrid SPECT/CT necessary for pre-interventional 3D quantification of relative lobar lung function?

Daniela Knollmann, Jerome Avondo, Wolfgang M. Schaefer
2018 European Journal of Hybrid Imaging  
In pulmonary malignancies pre-interventional 3D estimation of relative lobar perfusion is established to predict post-interventional functional outcome particularly in patients with borderline lung function. Aim was to test whether quantification from SPECT-scanners (non-hybrid) is as accurate as from SPECT/CTscanners (hybrid) when using dedicated software. Methods: Sixty-one patients suffering from pulmonary tumours underwent lung SPECT/CT using Tc-99m MAA to predict postoperative residual
more » ... function prior to surgical treatment. Quantification was done using "HERMES Hybrid 3D-Lung Lobe Quantification". In the hybrid approach SPECT and combined lowdoseCT/ diagnosticCT were used. In the non-hybrid approach SPECT and diagnosticCTs were used, lowdoseCTs were omitted. Bland Altman analysis was done to test for agreement. Results: Three hundred five lobes were quantified. Evaluation time was 6:37 ± 0. 55 min (hybrid) versus 6:34 ± 0.51 min (non-hybrid). Mean lobar value was 20.0 ± 10. 5% (range from 0 to 55%) for hybrid and 20.0 ± 10.6% (range from 0 to 58%) for the non-hybrid approach, mean absolute difference was 1.31%, no significant differences were found when analysing all values (p > 0.9). Correlation was excellent (R = 0.984, slope of the regression line 1.001 (p < 0.0001)). Intraclass correlation coefficient was 0. 9843. Bland Altman limits were -3.67% and 3.67%. Conclusion: Excellent concordance was found for 3D-quantification of relative lung perfusion when comparing a hybrid vs. non-hybrid approach. Using sophisticated software combining the generally available diagnosticCT and conventional SPECTdata reliable results for lobar perfusion can be obtained without the need for costly investment of SPECT/CT systems for this clinical question.
doi:10.1186/s41824-018-0036-0 fatcat:4hnjwvc7ujhodpykudwq6wp6na

Depression and anxiety as major determinants of neck pain: a cross-sectional study in general practice

Eva Blozik, Daria Laptinskaya, Christoph Herrmann-Lingen, Helene Schaefer, Michael M Kochen, Wolfgang Himmel, Martin Scherer
2009 BMC Musculoskeletal Disorders  
Although psychosocial factors are known to be highly linked with neck pain, current therapies focus on somatically based interventions such as medicinal or manipulatory therapies. This study examines how socio-demographic, psychosocial and medical history and healthpromoting lifestyle factors interact with neck pain in general practice patients. Methods: This is a cross-sectional survey including 448 patients from a general practice setting in Germany. Participants completed a comprehensive
more » ... tionnaire including the Neck Pain and Disability Scale German version (NPAD-d) and the Hospital Anxiety and Depression Scale. Crude and adjusted regression analyses were done to assess the relationship between neck pain and socio-demographic, psychosocial and medical history and health-promoting lifestyle factors. Results: Both in crude and adjusted regression analyses, depression and anxiety were highly significantly linked with increasing levels of neck pain. Educational level, deficits in social support and physical exercise were associated with neck pain in bivariate analyses, but these associations did not persist with adjustment for depression and anxiety. When investigating levels of depression and anxiety by NPAD-d quartile subgroups, those who were identified to have depressive mood or to be anxious were very likely to be in the group with the highest levels of neck pain. Conclusion: The higher the neck pain level, the more attention should be paid to psychosocial distress as a related burden. Further research is needed to elucidate the causality and the direction of the association between psychosocial distress and neck pain and to determine the benefit of psychosocial interventions.
doi:10.1186/1471-2474-10-13 pmid:19171034 pmcid:PMC2636754 fatcat:46k3fxdb35gw7lqkmyc3p6r7ei

MVAC-therapy for advanced urothelial carcinoma in an anuric renal transplant recipient

Fritz K. Matzkies, Bernd Tombach, Markus Dietrich, Klaus Kisters, Michael Barenbrock, Roland M. Schaefer, Wolfgang E. Berdel, Karl H. Rahn
2000 Nephrology, Dialysis and Transplantation  
Stö ckle M, Wellek S, Meyenburg W et al.  ...  McCaffrey JA, Hilton S, Mazumdar M et al.  ... 
doi:10.1093/ndt/15.1.110 pmid:10607779 fatcat:6krhmiosuvevzjeoue56ccznem

Q/V-SPECT CT in times of COVID-19: Changing the order to improve safety without sacrificing accuracy

Wolfgang M Schaefer, Daniela Knollmann, Philipp T Meyer
2021 Journal of Nuclear Medicine  
doi:10.2967/jnumed.120.261263 pmid:33963044 pmcid:PMC8882886 fatcat:c5prpyfhkvgeplnewdzm3ub5qu

Brain and Plasma Pharmacokinetics of Aripiprazole in Patients With Schizophrenia: An [18F]Fallypride PET Study

Gerhard Gründer, Christine Fellows, Hildegard Janouschek, Tanja Veselinovic, Christian Boy, Anno Bröcheler, Katrin M. Kirschbaum, Sandra Hellmann, Katja M. Spreckelmeyer, Christoph Hiemke, Frank Rösch, Wolfgang M. Schaefer (+1 others)
2008 American Journal of Psychiatry  
Objective: Aripiprazole at clinically effective doses occupies some 90% of striatal dopamine 2 and 3 (D 2 /D 3 ) receptors. In order to further characterize its extrastriatal and time-dependent binding characteristics, the authors conducted positron emission tomography (PET) studies with the D 2 /D 3 antagonist [ 18 F]fallypride at varying time points after the last aripiprazole administration in patients with schizophrenia. Method: Sixteen inpatients with a DSM-IV diagnosis of schizophrenia or
more » ... schizoaffective disorder receiving treatment with aripiprazole underwent an [ 18 F]fallypride PET scan. Receptor occupancy was calculated as the percentage reduction in binding potential relative to unblocked values measured in eight age-matched, medication-free patients with schizophrenia. In addition, aripiprazole serum concentrations were determined as part of a routine therapeutic drug monitoring program in a large group of patients (N=128) treated with aripiprazole. Results: Mean dopamine D 2 /D 3 receptor occupancy was high in all brain regions investigated, with no binding difference across brain regions. Nonlinear regression analysis revealed maximum attainable receptor occupancy (E max ) values close to saturation. The values for serum concentration predicted to provide 50% of E max (EC 50 ) were in the range of 5-10 ng/ml in all brain regions. The D 2 /D 3 receptors were completely saturated when serum aripiprazole concentration exceeded 100-150 ng/ml. The mean concentration in the large clinical patient sample was 228 ng/ml (SD=142). Conclusions: Because of its high affinity for D 2 /D 3 receptors and its long elimination half-life, aripiprazole at clinical doses occupies a high fraction of its target receptor everywhere in the brain. Its dissociation from those receptors is very slow, such that the authors calculate from the results that in patients with serum aripiprazole concentrations in the range typical for clinical practice, D 2 /D 3 receptors must remain nearly saturated for as long as 1 week after the last dose. (Am J Psychiatry Gründer et al.; AiA:1-8) AJP in Advance.
doi:10.1176/appi.ajp.2008.07101574 pmid:18381901 fatcat:lookdkkxzza5dej2po3fobfth4

Cardiac resynchronization therapyhomogenizes myocardial glucosemetabolism and perfusion in dilatedcardiomyopathy and left bundle branch block

Bernd Nowak, Anil M Sinha, Wolfgang M Schaefer, Karl-Christian Koch, Hans-Juergen Kaiser, Peter Hanrath, Udalrich Buell, Christoph Stellbrink
2003 Journal of the American College of Cardiology  
OBJECTIVES We investigated whether cardiac resynchronization therapy (CRT) affects myocardial glucose metabolism and perfusion in dilated cardiomyopathy (DCM) and left bundle branch block (LBBB). BACKGROUND Patients with DCM and LBBB present with asynchronous left ventricular (LV) activation, leading to reduced septal glucose metabolism. Cardiac resynchronization therapy recoordinates LV activation, but its effects on myocardial glucose metabolism and perfusion remain unknown. METHODS In 15
more » ... ents (10 females; 61 Ϯ 13 years) with DCM and LBBB (QRS width 165 Ϯ 15 ms), gated 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and technetium-99m ( 99m Tc)-sestamibi single-photon emission computed tomography were performed before and after two weeks of CRT. Uptake of FDG and 99m Tc-sestamibi was determined in four LV wall areas. Ejection fraction and volumes were calculated from gated PET. RESULTS Baseline FDG uptake was heterogeneous (p Ͻ 0.0001), with lowest uptake in the septal region (56 Ϯ 12%) and highest uptake in the lateral region (89 Ϯ 6%). During CRT, septal and anterior increases (p Ͻ 0.01) and lateral decreases (p Ͻ 0.01) resulted in homogeneously distributed glucose metabolism. Baseline heterogeneity (p Ͻ 0.0001) in 99m Tc-sestamibi uptake was modest (lowest septal 65 Ϯ 10%; maximum lateral 84 Ϯ 5%) and also reduced with CRT, although some heterogeneity (p Ͻ 0.05) remained. The septal-to-lateral ratio increased with CRT for FDG (0.62 Ϯ 0.12 to 0.91 Ϯ 0.26, p Ͻ 0.001) and 99m Tc-sestamibi uptake (0.77 Ϯ 0.13 to 0.85 Ϯ 0.16, p Ͻ 0.01). The LV end-diastolic and end-systolic volumes decreased from 293 Ϯ 160 to 272 Ϯ 158 ml (p Ͻ 0.05) and from 244 Ϯ 164 to 220 Ϯ 160 ml (p Ͻ 0.01), respectively. Ejection fraction increased from 22 Ϯ 12% to 25 Ϯ 13% (p Ͻ 0.01). CONCLUSIONS Glucose metabolism is reduced more than perfusion in the septal compared with LV lateral wall in patients with DCM and LBBB. Cardiac resynchronization therapy restores homogeneous myocardial glucose metabolism with less influence on perfusion. (J Am Coll Cardiol 2003;41:1523-8)
doi:10.1016/s0735-1097(03)00257-2 pmid:12742293 fatcat:s343xa7tsje3xnouqutmjibj7i

Configuration of the Optic Chiasm in Humans with Albinism as Revealed by Magnetic Resonance Imaging

Bernd Schmitz, Torsten Schaefer, Christoph M. Krick, Wolfgang Reith, Martin Backens, Barbara Ka¨smann-Kellner
2003 Investigative Ophthalmology and Visual Science  
PURPOSE. To determine whether the size and configuration of the optic chiasm in humans with albinism is different from that in normal control subjects. METHODS. Seventeen patients and 15 control subjects underwent magnetic resonance imaging of the entire head. Images were reformatted to the chiasm region and analyzed with observer-independent morphometry and measurements by a blinded observer. RESULTS. The albino group showed significantly smaller chiasmatic widths, smaller optic nerves and
more » ... ts, and wider angles between nerves and tracts. Statistical morphometry showed a different configuration of the optic chiasm. CONCLUSIONS. Size and configuration of the optic chiasm in humans with albinism are distinctly different from those in normal control subjects and reflect the atypical crossing of optic fibers. (Invest Ophthalmol Vis Sci. 2003;44:16 -21)
doi:10.1167/iovs.02-0156 pmid:12506050 fatcat:zthyroyaxzff5bju4i2f5cgwjy

Vulnerability to psychotogenic effects of ketamine is associated with elevated D2/3-receptor availability

Ingo Vernaleken, Majken Klomp, Olaf Moeller, Mardjan Raptis, Arne Nagels, Frank Rösch, Wolfgang M. Schaefer, Paul Cumming, Gerhard Gründer
2012 International Journal of Neuropsychopharmacology  
Previous positron emission tomography (PET) studies employing competition paradigms have shown either no change or substantial declines in striatal [ 11 C]-raclopride binding after challenge with psychotogenic doses of the N-methyl-D-aspartate antagonist ketamine. We sought to probe the relationship between the severity of ketamine-induced psychotic symptoms and altered dopamine D 2/3 receptor availability throughout brain using the high affinity ligand [ 18 F]-fallypride (FP). PET recordings
more » ... re obtained in a group of 10 healthy, young male volunteers, in a placebo condition, and in the course of an infusion with ketamine at a psychotomimetic dose. Administration of the Positive and Negative Syndrome Scale and the Thought and Language Index in both conditions revealed a substantial emergence of mainly negative symptoms of schizophrenia, persisting until the end of the 3 h PET recordings. The baseline FP binding in cortex, caudate nucleus and other brain regions was highly predictive of the individual severity of psychotic symptoms in the ketamine condition. However, there was no evidence of ketamine-evoked reductions in FP binding. In the context of earlier findings, we speculate that high baseline D 2/3 -receptor availability may impart benefits with regard to cognitive flexibility, but increases the risk of maladaptive information processing in the face of environmental stresses and challenges.
doi:10.1017/s1461145712000764 pmid:22906553 fatcat:ovnunnfrnjarzjpq5caolqwlku

Comparison of regional myocardial blood flow and perfusion in dilated cardiomyopathy and left bundle branch block: role of wall thickening

Bernd Nowak, Christoph Stellbrink, Wolfgang M Schaefer, Anil M Sinha, Ole A Breithardt, Hans-Juergen Kaiser, Patrick Reinartz, Peter Hanrath, Ulrich Buell
2004 Journal of Nuclear Medicine  
This finding was confirmed by M-mode echocardiography from corresponding regions.  ...  Values were determined from parasternal echocardiographic M-mode recordings. TABLE 1 1 Clinical Characteristics Patient no.  ... 
pmid:15001681 fatcat:gf64awh36naajb7joviycr4lvi

HMG-CoA reductase inhibitors in kidney transplant recipients receiving tacrolimus: statins not associated with improved patient or graft survival

Nizar Younas, Christine M Wu, Ron Shapiro, Jerry McCauley, James Johnston, Henkie Tan, Amit Basu, Heidi Schaefer, Cynthia Smetanka, Wolfgang C Winkelmayer, Mark Unruh
2010 BMC Nephrology  
0.6 ± 0.4 0.61 HbsAg positive (%; N = 615) 2.3 0.5 1.1 0.05 Anti-HCV positive (%; N = 615) 6.3 8.4 7.6 0.59 CMV IgG positive (%; N = 612)* 73.3 81.3 78.4 0.02 Total cholesterol (3 m)  ...  transplant (y; N = 615)* 51 ± 12 48 ± 15 50 0.002 Male (%; N = 614) 62.4 63.3 63.0 0.82 Race (N = 615) White (%) 86.9 81.5 83.4 0.08 Other (%) 13.1 18.5 16.6 Body Mass Index (kg/m  ... 
doi:10.1186/1471-2369-11-5 pmid:20359353 pmcid:PMC2855559 fatcat:6mrpmdotbjal7ev3pyzoutexbe

Myocardial viability assessment by endocardial electroanatomic mapping: comparison with metabolic imaging and functional recovery after coronary revascularization

Karl-Christian Koch, Juergen vom Dahl, Monika Wenderdel, Bernd Nowak, Wolfgang M Schaefer, Alexander Sasse, Christoph Stellbrink, Udalrich Buell, Peter Hanrath
2001 Journal of the American College of Cardiology  
OBJECTIVES The objective of this study was to compare electroanatomic mapping for the assessment of myocardial viability with nuclear metabolic imaging using positron emission computed tomography (PET) and with data on functional recovery after successful myocardial revascularization. BACKGROUND Animal experiments and first clinical studies suggested that electroanatomic endocardial mapping identifies the presence and absence of myocardial viability. METHODS Forty-six patients with prior (Ն2
more » ... ks) myocardial infarction underwent fluorine-18 fluorodeoxyglucose (FDG) PET and Tc-99m sestamibi single-photon emission computed tomography (SPECT) before mapping and percutaneous coronary revascularization. The left ventricular endocardium was mapped and divided into 12 regions, which were assigned to corresponding nuclear regions. Functional recovery using the centerline method was assessed in 25 patients with a follow-up angiography. RESULTS Regional unipolar electrogram amplitude was 11.0 mV Ϯ 3.6 mV in regions with normal perfusion, 9.0 mV Ϯ 2.8 mV in regions with reduced perfusion and preserved FDG-uptake and 6.5 mV Ϯ 2.6 mV in scar regions (p Ͻ 0.001 for all comparisons). At a threshold amplitude of 7.5 mV, the sensitivity and specificity for detecting viable (by PET/SPECT) myocardium were 77% and 75%, respectively. In infarct areas with electrogram amplitudes Ͼ7.5 mV, improvement of regional wall motion (RWM) from Ϫ2.4 SD/chord Ϯ 1.0 SD/chord to Ϫ1.5 SD/chord Ϯ 1.1 SD/chord (p Ͻ 0.01) was observed, whereas, in infarct areas with amplitudes Ͻ7.5 mV, RWM remained unchanged at follow-up (Ϫ2.3 SD/ chord Ϯ 0.7 SD/chord to Ϫ2.4 SD/chord Ϯ 0.7 SD/chord). CONCLUSIONS These data suggest that the regional unipolar electrogram amplitude is a marker for myocardial viability and that electroanatomic mapping can be used for viability assessment in the catheterization laboratory. (J Am Coll Cardiol 2001;38:91-8)
doi:10.1016/s0735-1097(01)01314-6 pmid:11451302 fatcat:ckymio6lvfhdxk3pyopreyk7py

Comparison of microsphere-equivalent blood flow (15O-water PET) and relative perfusion (99mTc-tetrofosmin SPECT) in myocardium showing metabolism-perfusion mismatch

Wolfgang M Schaefer, Bernd Nowak, Hans-Juergen Kaiser, Karl-Christian Koch, Stephan Block, Juergen vom Dahl, Udalrich Buell
2003 Journal of Nuclear Medicine  
MATERIALS AND METHODS Patients Forty-two consecutively admitted patients (35 men, 7 women; mean age Ϯ SD, 63 Ϯ 11 y; age range, 40 -78 y; mean body mass index, 26.0 Ϯ 3.3 kg . m Ϫ2 ) with severe CAD  ...  Arbab et al. also reported that 99m Tc-tetrofosmin-incubated cells released 38% of the accumulated tracer if they were treated with carbonyl cyanide m-chlorophenylhydrazone, an uncoupler of oxidative phosphorylation  ... 
pmid:12515874 fatcat:wnw6u6hrqzglzaaqf6c5zsf43a

CFTR and sphingolipids mediate hypoxic pulmonary vasoconstriction

Christoph Tabeling, Hanpo Yu, Liming Wang, Hannes Ranke, Neil M. Goldenberg, Diana Zabini, Elena Noe, Adrienn Krauszman, Birgitt Gutbier, Jun Yin, Michael Schaefer, Christoph Arenz (+5 others)
2015 Proceedings of the National Academy of Sciences of the United States of America  
*P ≤ 0.05, **P ≤ 0.01 vs. control group. thickness of small (20-50 μm), medium-sized (50-100 μm), and large pulmonary arteries (100-150 μm) (Fig. 2 B and C) ; and a higher degree of muscularization in  ...  Schaefer, Rudolf-Boehm-Institute of Pharmacology and Toxicology, University of Leipzig, Leipzig, Germany), acid sphingomyelinase (aSMase) inhibitor ARC39 (10 μmol/L; provided by C.  ... 
doi:10.1073/pnas.1421190112 pmid:25829545 pmcid:PMC4386337 fatcat:p5rsvgvwzrhlfohmknbqzy5pja

Prone versus supine patient positioning during gated 99mTc-sestamibi SPECT: effect on left ventricular volumes, ejection fraction, and heart rate

Wolfgang M Schaefer, Claudia S A Lipke, Harald P Kühl, Karl-Christian Koch, Hans-Juergen Kaiser, Patrick Reinartz, Bernd Nowak, Udalrich Buell
2004 Journal of Nuclear Medicine  
MATERIALS AND METHODS Study Population Forty-eight patients (36 men and 12 women; mean age, 59 Ϯ 13 y; age range, 33-82 y; body-mass index, 28.3 Ϯ 4.0 kg ϫ m Ϫ2 ) scheduled for routine myocardial perfusion  ...  Heart rate was significantly higher for prone than for supine acquisitions in PRONE VERSUS SUPINE GATED SPECT • Schaefer et al. both groups (smaller-ventricle group, 70.4 min Ϫ1 for prone vs. 68.2 min  ... 
pmid:15585475 fatcat:4deoa4jvibhgln4rwj4ctpeac4

Landscape genetics of California mule deer (Odocoileus hemionus): the roles of ecological and historical factors in generating differentiation

KATHERINE M. PEASE, ADAM H. FREEDMAN, JOHN P. POLLINGER, JOHN E. MCCORMACK, WOLFGANG BUERMANN, JEFF RODZEN, JIM BANKS, ERIN MEREDITH, VERNON C. BLEICH, ROBERT J. SCHAEFER, KEN JONES, ROBERT K. WAYNE
2009 Molecular Ecology  
John McCormack and Wolfgang Buermann are members of the Center for Tropical Research at UCLA.  ...  For the 10 loci typed at UCLA, an M-13 hybrid primer process was used to dye-label the primer (Boutin-Ganache et al. 2001) .  ... 
doi:10.1111/j.1365-294x.2009.04112.x pmid:19302356 fatcat:btmmttdxlncajhpetncoxgeuyi
« Previous Showing results 1 — 15 out of 2,375 results