bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of an Intravenously Injected Bolus
Authors: Samuel A. M. , Raikar U. R. , Atmaram S. H. , Ganatra R. D. 
Published: March 2018

SummaryA study of some parameters affecting the time activity histogram of an intravenous bolus injection of radioactivity was performed. A scoring system for bolus compactness was attempted. A score of 2 and above was considered to be a satisfactory bolus. Volumes less than 1 ml tended to result in a satisfactory bolus. The nature of radiopharmaceutical injected, different injecters and age of the patient did not affect the score. Thyrotoxic patients gave the best bolus score.
Mechanism of 67Ga Accumulation in Normal Rat Liver Lysosomes
Authors: Gebhardt A. , Schulz E. , Haubold U. , Hristowa M. , Zeggel B. , Aulbert E. 
Published: March 2018

Summary
67Ga accumulates in various malignant tumors and parenchymatous tissues. It was found to be associated with the soluble fraction of lysosomes (11). The present work investigates the mechanism of 67Ga accumulation in normal liver cells.Lysosomes were isolated from rat liver after intravenous injection of carrier free 67Ga. The soluble lysosomal fraction was obtained by sonication followed by centrifugation at 105,000 xg for 2 hrs. Gel filtration on Sephadex G 25 superfine was carried out on the soluble lysosomal fraction in order to investigate the stability of the 67Ga-protein complex within the lysosomes under EDTA treatment. After treatment with 1 mM/1 EDTA a considerable amount of the protein bound radioactivity was found to be liberated. In further experiments the 67Ga binding lysosomal proteins were fractionated by electrophoresis on 7% Polyacrylamide gels (0.5 cm x 5.5 cm). After staining with Coomassie blue 18 separated protein bands were apparent. 67Ga distribution within the gels was assessed by direct counting of radioactivity in gel slices. A considerable amount of the intralysosomal protein bound radioactivity migrated with a relative mobility of 0.36 corresponding to a protein band of molecular weight 85,000 — 90,000. This peak corresponded to the peak of 67Ga labeled purified transferrin in control gels. These data were confirmed by Immunoelectrophoresis combined with autoradiography: within the soluble lysosomal fraction a slight transferrin line could be identified.We conclude that 67Ga which is transported in the blood by transferrin (23) and taken up by the hepatic cell through endocytosis (32) is accumulated in the lysosomes associated with transferrin and its degraded fragments.
Attenuation correction for myocardial perfusion imaging
Authors: Khorsand A. , Stix G. , Nekolla S. , Becherer A. , Kletter K. , Dudczak R. , Sochor H. , Maurer G. , Porenta G. , Graf S. 
Published: March 2018

SummaryAim: We investigated the impact of photon attenuation in myocardial perfusion imaging with SPECT and PET in patients with coronary artery disease. In fact, the regional tracer distribution can be quantitatively assessed by polar map analysis if the effects of photon attenuation are accounted for. PET imaging permits accurate measurement of and correction for photon attenuation, whereas results of attenuation correction in SPECT imaging have been inconsistent. Patients, methods: We compared photon attenuation in resting perfusion imaging studies with SPECT (99mTc-sestamibi) and PET (13N-ammonia) from 21 patients. Transaxial images were reconstructed with and without attenuation correction and reoriented into short axis images. Polar map analysis was utilized to generate regional tracer uptake in six anatomical segments. Results: Average segmental photon attenuation calculated as the ratio of counts in corrected and uncorrected images was 7.2 ± 1.4 in SPECT and 14.0 ± 3.1 in PET imaging (p <0.01). This attenuation factor was significantly related to body mass index for both methods (p <0.001). While attenuation correction for SPECT imaging did compensate for attenuation effects in the inferior wall (from –15% to +6% vs. PET), relative tracer uptake in the anterior wall in SPECT images was significantly reduced after attenuation correction (from –2% to –18% vs. PET, p <0.01). Conclusion: Differential effects of attenuation correction for myocardial SPECT perfusion imaging need to be considered when algorithms designed to compensate effects of photon attenuation in SPECT imaging are employed in clinical practice.
FDG gamma camera PET equipped with one inch crystal and XCT
Authors: Khorsand A. , Graf S. , Dobrozemsky G. , Oezer S. , Kletter K. , Dudczak R. , Pirich C. , Beheshti M. 
Published: March 2018

SummaryMetabolic imaging with 2-[fluorine-18]-fluoro- 2-deoxy-D-glucose (FDG) is actually considered as the best method to detect and quantitatively assess myocardial tissue viability. The aim of this study was to investigate the accuracy of FDG gamma camera positron emission tomography (GCPET) imaging equipped with one inch NaI crystals in comparison to FDG dedicated PET (dPET) imaging as a „gold standard“ in phantom and clinical studies. Patients, methods: Nineteen patients with coronary artery disease (CAD) underwent both imaging modalities. Phantom and clinical GCPET imaging were performed with a dual-headed, coincidence based gamma camera equipped with 1 inch thick NaI crystals and an x-ray tube (XCT) for attenuation correction (AC), as well as with a dedicated PET scanner with AC. 99mTc tetrofosmin single-photon emission tomography (SPET) studies were performed for assessment of myocardial perfusion, with AC. Results: Phantom studies showed a significant relation in segmental activity between FDG imaging with AC using GCPET and dPET (r = 0.91, p <0.001). In clinical studies with AC correlation coefficients of mean segmental FDG uptake and regional defect size were r = 0.87 (p <0.0001) and r = 0.83 (p <0.0001), respectively. In regional analysis close agreement was even found in the most attenuated regions of the heart if AC was used in GCPET imaging. The overall agreement for detection of viable myocardium was 81% between FDG-dPET (AC) and FDG-GCPET (AC) and 74% between FDG-dPET (AC) and FDG-GCPET (NC). Conclusion: This study suggests that the assessment of myocardial metabolism by means of FDG is feasible with a coincidence based gamma camera equipped with 1 inch thick NaI crystals if AC is performed. The results reveal a close concordance and agreement between FDG-dPET (AC) and FDG-GCPET (AC) as compared to FDG-GCPET (NC).
Use of statistical parametric mapping of 18F-FDG-PET in frontal lobe epilepsy
Authors: Amthauer H. , Merschhemke M. , Lüdemann L. , Hartkop E. , Ruf J. , Gutberlet M. , Bertram H. , Meencke H.-J. , Felix R. , Venz St. , Plotkin M. 
Published: March 2018

Summary:
Aim: Evaluation of the use of statistical parametrical mapping (SPM) of FDG-PET for seizure lateralization in frontal lobe epilepsy. Patients: 38 patients with suspected frontal lobe epilepsy supported by clinical findings and video-EEG monitoring. Method: Statistical parametrical maps were generated by subtraction of individual scans from a control group, formed by 16 patients with negative neurological/psychiatric history and no abnormalities in the MR scan. The scans were also analyzed visually as well as semiquantitatively by manually drawn ROIs. Results: SPM showed a better accordance to the results of surface EEG monitoring compared with visual scan analysis and ROI quantification. In comparison with intracranial EEG recordings, the best performance was achieved by combining the ROI based quantification with SPM analysis. Conclusion: These findings suggest that SPM analysis of FDG-PET data could be a useful as complementary tool in the evaluation of seizure focus lateralization in patients with supposed frontal lobe epilepsy.
Radiation exposure of patients undergoing nuclear medicine procedures in Germany between 1996 and 2000
Authors: Schnell-Inderst P. , Noßke D. , Weiss M. , Stamm-Meyer A. , Brix G. , Hahn K. , Hacker M. 
Published: March 2018

Summary:The aim of this study was to estimate both the frequency and effective dose of nuclear medicine procedures performed in Germany between 1996 and 2000 for different subgroups of patients. Methods: Electronically archived data from 14 hospitals and 10 private practices were restored and statistically analyzed. The effective dose per examination was calculated according to ICRP publication 80 using the tissue weighting factors given in ICRP publication 60. Based on the data collected, statistical parameters were computed to characterize the frequency and effective dose of the various nuclear medicine procedures. Results: In total, 604,771 nuclear medicine procedures performed in 433,709 patients were analyzed. On average, 1.4 examinations were carried out per patient and year. The median effective dose was 1.7 [5.-95. percentile; mean: 0.4–8.5; 2.9] mSv per examination and 2.3 [0.5–11.2; 3.5] mSv per patient. Interestingly, the mean effective dose per examination, but not the number of examinations per year increased with the age of the patients. Most frequent were examinations of the thyroid (36.7%), the skeleton (27.1%) and the cardiovascular system (11.1%), which were associated with a median effective dose of 0.5 [0.5–1.1; 0.7] mSv, 3.4 [2.9–5.1; 3.6] mSv and 7.3 [3.2–21.0; 9.5] mSv, respectively. Over the five-year period examined, the total annual number of PET procedures (222.3%) as well as of examinations of thyroid (24.5%), skeleton (17.9%), and the cardiovascular system (14.9%) increased markedly, whereas a decrease was observed for brain (-39.3%), lung (-20.2%) and renal (-15.0%) scans. Conclusion: The age- and gender-specific data presented in this study provide detailed public health information on both the current status and recent trends in the practice of diagnostic nuclear medicine examinations.
Comparison of manual and automated quantification methods of 123I-ADAM
Authors: Koskela A. , Diemling M. , Keski-Rahkonen A. , Sihvola E. , Ahonen A. , Kauppinen T. 
Published: March 2018

Summary:
123I-ADAM is a novel radioligand for imaging of the brain serotonin transporters (SERTs). Traditionally, the analysis of brain receptor studies has been based on observer-dependent manual region of interest definitions and visual interpretation. Our aim was to create a template for automated image registrations and volume of interest (VOI) quantifications and to show that an automated quantification method of 123I-ADAM is more repeatable than the manual method. Patients, methods: A template and a predefined VOI map was created from 123I-ADAM scans done for healthy volunteers (n = 15). Scans of another group of healthy persons (HS, n = 12) and patients with bulimia nervosa (BN, n = 10) were automatically fitted to the template and specific binding ratios (SBRs) were calculated by using the VOI map. Manual VOI definitions were done for the HS and BN groups by both one and two observers. The repeatability of the automated method was evaluated by using the BN group. Results: For the manual method, the interobserver coefficient of repeatability was 0.61 for the HS group and 1.00 for the BN group. The intraobserver coefficient of repeatability for the BN group was 0.70. For the automated method, the coefficient of repeatability was 0.13 for SBRs in midbrain. Conclusion: An automated quantification gives valuable information in addition to visual interpretation decreasing also the total image handling time and giving clear advantages for research work. An automated method for analysing 123I-ADAM binding to the brain SERT gives repeatable results for fitting the studies to the template and for calculating SBRs, and could therefore replace manual methods.
Combined 18F-FDG-PET/CT imaging of the head and neck
Authors: Raupach R. , Beyer T. , Schäfers K. P. 
Published: March 2018

Summary:PET/CT imaging is particularly promising for head/neck malignancies, but dental implants lead to biased CT attenuation and PET activity values following CT-based attenuation correction (CT-AC). Objective: Here, we implement a metal artifact correction procedure (MAR) as part of the CT-AC for PET/CT imaging. Results: Phantom studies indicate a maximum quantitative bias in CT and PET of 1000 HU and 30 %, which is reduced to 230 HU and 6 %, respectively following MAR. These results were verified in selected patients. Conclusion: Artifacts and biases from dental implants can be reduced in PET/CT imaging by applying a simple MAR as part of the CT-AC.
Joint accumulations of FDG in whole body PET scans
Authors: Meier N. , Stumpe K. D. M. , von Schulthess G. K. 
Published: March 2018

Summary
Purpose: To retrospectively evaluate FDG accumulations in major joints in a large series of non-absorption corrected partial body and whole body FDG-PET scans, and to determine the frequency and intensity of accumulation. Materials and methods: 354 consecutive PET partialand whole body non-transmission corrected scans of patients obtained for tumor staging were examined with respect to FDG accumulations in the acromio-clavicular (AC)-, gleno-humeral-, hip-, knee- and talo-tlblal joints. FDG-uptake was graded using a semi-quantitative scale from 0 (no accumulation) to 4 (very strong accumulation comparable to brain uptake). Results: Joint activity of grade 1-2 was noted frequently, while grade 3 was rare, occurring only in the knee and shoulder joints, and grade 4 was inexistent. The 43 patients with grade 3 accumulations or with at least 4 joints showing grade 2 uptake were interviewed, but all denied pain specifically referred to a joint. Joint accumulations were seen in 50% of the acromio-clavicular-, 80% in the gleno-humeral-, 50% in the hip-, 90% in the knee and 80% in the talo-tibial joints. The intensities of joint accumulations correlated positively and significantly with patient age, ranging from r = 0.7 and ñ <0.05 in the knee to r = 0.96 and ñ <0.0001 in the AC joint. Conclusions: FDG accumulations in the joints in whole body FDG-PET scans are frequent and are very likely not related to symptoms. As there is a strong age correlation, and FDG is known to accumulate in inflammatory lesions, the findings are most likely a result of sub-clinical inflammatory synovial proliferation or other chronic inflammatory processes occurring in aging joints.
FDG PET and CT in locally advanced adenocarcinomas of the distal oesophagus
Authors: Stollfuss J. , Ott K. , Wieder H. , Fink U. , Schwaiger M. , Weber W. A. , Stahl A. 
Published: March 2018

SummaryAim: The incidence of adenocarcinomas of the distal oesophagus (ADE) has dramatically increased in Western countries. The clinical importance of a FDG PET finding discordant with CT was determined in patients with locally advanced ADE. In addition, tumour standardized uptake values (SUV) were correlated with patient survival. Patients, methods: 40 consecutive patients were analyzed retrospectively. All patients underwent an attenuation corrected FDG PET scan (neck, chest, abdomen) and contrast enhanced helical CT of the chest and abdomen. PET and CT scans were reviewed independently and concomitantly with respect to metastases in predefined lymph node sites and organs. Any discordance between PET and CT was assessed for clinical relevance. Clinical relevance was defined as a change in the overall therapeutic concept (curative vs. palliative). Follow-up imaging and histological evaluation served as the gold standard. Mean tumour SUVs were determined by 1.5 cm regions of interest placed over the tumour’s maximum. Results: When read independently from the CT scan FDG PET indicated a clinically relevant change in tumour stage in 9/40 patients (23%) and a non-relevant change in 11/40 patients (28%). PET was correct in 5/9 patients (56%) with clinically relevant discordances. In 4/9 patients PET was incorrect (3 false positive due to suspicion of M1-lymph nodes or lung metastases, 1 false negative in disseminated liver metastases). With concomitant reading, PET indicated a clinically relevant change in tumour stage in 6/40 patients (15%) and a non-relevant change in 5/40 patients (13%). PET was correct in 5/6 patients (83%) with clinically relevant discordances. The patient with disseminated liver disease remained the single false negative. Overall, the benefit from PET was based on its higher diagnostic accuracy at organ sites. Tumour SUV did not correlate with patient survival. Conclusion: About half of discordances between FDG PET and CT are clinically relevant. Concomitant reading of PET and CT is advisable as it reduces the overall rate of discordances and enhances the accuracy of PET in clinical relevant discordances (from 56% to 83%).
State-of-the-art of small animal imaging with high-resolution SPECT
Authors: Wirrwar A. , Antke C. , Kley K. , Müller H.-W. , Nikolaus S. 
Published: March 2018

SummaryDuring the recent years, in vivo imaging of small animals using SPECT has become of growing relevance. Along with the development of dedicated high-resolution small animal SPECT cameras, an increasing number of conventional clinical scanners has been equipped with single or multipinhole collimators. This paper reviews the small animal tomographs, which are operating at present and compares their performance characteristics. Furthermore, we describe the in vivo imaging studies, which have been performed so far with the individual scanners and survey current approaches to optimize molecular imaging with small animal SPECT.
Wie sicher sind pädiatrische Arzneimittelverordnungen?
Authors: Grimm Martin , Gebauer Corinna , Kapellen Thomas , Brosteanu Oana , Kiess Wieland 
Published: March 2018

ZusammenfassungHintergrund: Viele pädiatrisch eingesetzte Arzneimittel sind für Kinder nicht zugelassen. Der Mangel an Informationen zu Anwendung und Nebenwirkungen ist in der Frühgeborenen- und Intensivmedizin besonders hoch.Ziel: Das Ziel bestand in der Untersuchung des Zulassungsstatus der Medikamentenverordnungen an einer universitären Kinderklinik zur Priorisierung und Planung von Arzneimittelstudien.Material und Methoden: Auf einer interdisziplinären, einer neonatologischen Intensivstation und einer allgemeinpädiatrischen Station wurden über einen Zeitraum von 3 Monaten alle Arzneimittelverordnungen erfasst. Zur Analyse des Zulassungsstatus dienten die „Rote Liste®” und die Fachinformationen.Ergebnisse: 377 Patienten erhielten 2486 Verordnungen. Die häufigsten Arzneimittel waren Paracetamol, Vitamin K und Acetylcystein (ACC). Unlizensiert waren 5,5% aller Verordnungen; 39,5% wurden außerhalb der Altersgrenzen, 16,7% mit nicht zugelassener Indikation angewendet.Schlussfolgerung: Die unlizensierte und Off-Label-Arzneimittelanwendung ist noch weit verbreitet. Durch systematische Analysen können in Zusammenarbeit mit EMEA (European Medicines Agency) und PAED-Net Prioritätenlisten für Studien erstellt werden, die die Arzneimittelsicherheit erhöhen.
Diagnostik und Therapie der Hüftdysplasie
Authors: Ziegler Jörg , Günther Klaus Peter , Thielemann Falk 
Published: March 2018

ZusammenfassungHüftreifungsstörungen zählen zu den häufigsten Skeletterkrankungen weltweit. Zwischen 2–4% der Säuglingshüften in deutschsprachigen Ländern zeigen sonografische Merkmale einer relevanten Entwicklungsverzögerung d. h. Dysplasie. Genetische, hormonelle und mechanische Faktoren spielen ätiologisch bei der Entstehung einer Hüftdysplasie oder -luxation eine Rolle. Prinzipiell können Hüftreifungsstörungen damit zu jedem Zeitpunkt der kindlichen Entwicklung manifest werden.Instabilitätszeichen der Hüfte, seitendifferente Bewegungsmuster, Beinlängendifferenzen oder funktionelle Beschwerden sind klinische Hinweiszeichen dieser Fehlentwicklung.Die Etablierung eines geeigneten klinischen und sonografischen Screeningverfahrens und eines stadienabhängigen Therapieprogrammes war Grundvoraussetzung einer statistisch nachweisbaren Senkung notwendiger erster operativer Behandlungsmaßnahmen. Restdysplasien oder Reifungsstörungen, die sich erst in der weiteren Entwicklung manifestieren, können durch operative Reorientierungen an der Hüftpfanne und seltener auch am koxalen Femurende wirkungsvoll behandelt werden. Die Entstehung einer sekundären Arthrose als Spätfolge einer dysplastischen Hüftreifung lässt sich bei der Mehrzahl der Kinder damit vermeiden.Die frühe Diagnosestellung und adäquate Behandlung der Hüftreifungsstörung sind gute prognostische Faktoren.
Der Kurzdarm-Patient
Authors: Reinshagen Konrad , Waag Karl-Ludwig 
Published: March 2018

ZusammenfassungEs wird über 53 Patienten mit einem Kurzdarm und einem mittleren Alter von 25 Monaten berichtet, die nach der Methode von Bianchi einer longitudinalen Halbierung des Darmes zur Darmverlängerung aufgrund eines Kurzdarmsyndroms unterzogen wurden. Die Operationsindikation ergab sich aus der Notwendigkeit persistierender parenteraler Ernährung, aus der aggravierenden Cholestase, aus unkontrollierbarer Stuhlfrequenz und Stuhlqualität und aus der Ausschöpfung der letzten adäquaten zentral-venösen Zugänge.Das Follow-up betrug 79,5 Monate. 77,36% aller Patienten haben bis heute überlebt. 80% der Patienten werden langfristig komplett enteral ernährt.Darmverlängerungsoperationen sind bei Patienten mit einem Kurzdarmsyndrom, die eine sekundäre Dünndarmdilatation und noch keine irreversible Leberfunktionsstörung zeigen, die Therapie der ersten Wahl. Der Transplantation sollten nur solche Patienten zugeführt werden, die nach der Dünndarmverlängerung nicht von der parenteralen Ernährung entwöhnt werden können und eine zunehmende Leberfunktionsstörung entwickeln.
Adipositaschirurgie im Kindesund Jugendalter
Authors: Blüher Susann , Keller Alexandra , Till Holger , Muensterer Oliver 
Published: March 2018

ZusammenfassungSowohl Prävalenz als auch Ausmaß der Adipositas haben im Kindes- und Jugendalter in den letzten Jahrzehnten drastisch zugenommen. Im Gegensatz zu Erwachsenen gibt es für die operative Behandlung der morbiden Adipositas im Kindes- und Jugendalter kaum Erfahrungen. Sie lehnen sich hauptsächlich an die bereits etablierten Techniken in der Allgemeinchirurgie an. Am häufigsten wird das Magenbanding, die Roux-en-Y-Bypassoperation, die Schlauchmagenplastik oder die Platzierung eines Magenballons durchgeführt. Ziel der Behandlung ist neben einer Verbesserung der Lebensqualität vor allem die Besserung bereits vorhandener metabolischer, kardiovaskulärer und orthopädischer Begleiterkrankungen (arterieller Hypertonus, Typ-2-Diabetes mellitus, Fettstoffwechselstörungen, Hyperurikämie, Gelenkprobleme oder Schlafapnoe). Die publizierten klinischen Studien zeigen eine hohe Effektivität für die postoperative Gewichtsabnahme, wobei langfristige Ergebnisse bei Kindern noch nicht vorliegen. Aufgrund der präoperativ bestehenden Sekundärerkrankungen und des massiven Übergewichts ist die Adipositaschirurgie allerdings mit spezifischen Risiken behaftet. Alle Patienten bedürfen daher neben einer sorgfältigen, postoperativen Evaluierung und Risikostratifizierung einer interdisziplinären Betreuung in einem spezialisierten Zentrum.
Thorakoskopie im Kindesalter
Authors: Metzelder Martin , Glüer Sylvia , Ure Benno 
Published: March 2018

ZusammenfassungThorakoskopische Techniken kommen heute bei Kindern zur Diagnostik und Therapie zahlreicher Krankheitsbilder zur Anwendung. Mehr als 20 Eingriffstypen sind für alle Altersgruppen einschließlich Neugeborener beschrieben. Belegt ist, dass minimal-invasive Techniken im Thorax unter Berücksichtigung der speziellen Verhältnisse des Kindes sicher und zuverlässig anwendbar sind. Studien belegen zudem eine niedrigere Morbidität, verkürzte Krankenhausverweildauer, niedrigere Kosten und ein besseres kosmetisches Ergebnis. Die funktionellen Resultate sind mit denen der konventionellen Thoraxchirurgie vergleichbar. Limitiert ist der Einsatz minimal-invasiver Techniken bei onkologischen Erkrankungen, insbesondere bei der Resektion thorakaler Tumoren, für die bisher Erfahrungen aus nur wenigen Zentren mit niedrigen Fallzahlen vorliegen. Dieser Artikel gibt einen Überblick über das Spektrum der derzeit am häufigsten und mit einer gewissen Standardisierung durchgeführten thorakoskopischen Eingriffe im Kindesalter.