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2.
Altan Ahmed John A. Stauffer Jordan D. LeGout Justin Burns Kristopher Croome Ricardo Paz-Fumagalli Gregory Frey Beau Toskich 《Journal of gastrointestinal oncology.》2021,12(2):751
BackgroundNeoadjuvant yttrium-90 transarterial radioembolization (TARE) is increasingly being used as a strategy to facilitate resection of otherwise unresectable tumors due to its ability to generate both tumor response and remnant liver hypertrophy. Perioperative outcomes after the use of neoadjuvant lobar TARE remain underinvestigated.MethodsA single center retrospective review of patients who underwent lobar TARE prior to major hepatectomy for primary or metastatic liver cancer between 2007 and 2018 was conducted. Baseline demographics, radioembolization parameters, pre- and post-radioembolization volumetrics, intra-operative surgical data, adverse events, and post-operative outcomes were analyzed.ResultsTwenty-six patients underwent major hepatectomy after neoadjuvant lobar TARE. The mean age was 58.3 years (17–88 years). 62% of patients (n=16) had primary liver malignancies while the remainder had metastatic disease. Liver resection included right hepatectomy or trisegmentectomy, left or extended left hepatectomy, and sectorectomy/segmentectomy in 77% (n=20), 8% (n=2), and 15% (n=4) of patients, respectively. The mean length of stay was 8.3 days (range, 3–33 days) and there were no grade IV morbidities or 90-day mortalities. The incidence of post hepatectomy liver failure (PHLF) was 3.8% (n=1). The median time to progression after resection was 4.5 months (range, 3.3–10 months). Twenty-three percent (n=6) of patients had no recurrence. The median survival was 28.9 months (range, 16.9–46.8 months) from major hepatectomy and 37.6 months (range, 25.2–53.1 months) from TARE.ConclusionsMajor hepatectomy after neoadjuvant lobar radioembolization is safe with a low incidence of PHLF. 相似文献
3.
Factors predicting tracer uptake in somatostatin receptor and MIBG scintigraphy of metastatic gastroenteropancreatic neuroendocrine tumors. 总被引:1,自引:0,他引:1
Samer Ezziddin Timur Logvinski Charlotte Yong-Hing Hojjat Ahmadzadehfar Hans-Peter Fischer Holger Palmedo Jan Bucerius Michael J Reinhardt Hans-Jürgen Biersack 《Journal of nuclear medicine》2006,47(2):223-233
Radiolabeled octreotide analogs (Oct) and metaiodobenzylguanidine (MIBG) offer 2 different approaches for imaging and targeting metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NET). Despite successful establishment of the revised World Health Organization (WHO) classification, which distinguishes between low- and high-grade malignant GEP-NET, there is a lack of scintigraphic studies comparing uptake behavior on the basis of this categorization. This study aims to define predisposing factors of tracer uptake for both imaging principles implementing the updated tumor criteria of the current WHO classification. METHODS: Fifty-seven consecutive patients with histologically confirmed metastatic GEP-NET evaluated with both 111In-pentetreotide and 123I/131I-MIBG scintigraphy were included in this study. Intensity of tracer uptake was graded according to the different metastatic regions. Patients were classified as overall positive when avid uptake in the clinically relevant tumor lesions was present. Correlation was tested between the proportion of positive patients and tumor origin, function, and malignancy. RESULTS: Overall, 52 patients (91.2%) were Oct positive and 28 patients (49.1%) were MIBG positive. The proportion of tracer-positive patients was significantly higher (P < 0.05) in low-grade malignant tumors for both tracers and in functioning as well as in gastroenteral NET for MIBG. Five patients were negative for both tracers. None of the Oct-negative patients proved to be MIBG positive. CONCLUSION: Oct affinity is observed with high frequency throughout the subgroups of metastatic GEP-NET, whereas corresponding MIBG uptake is overall less prevalent and more group dependent. Tumor differentiation significantly impacts both Oct and MIBG uptake, whereas functionality predisposes only for MIBG accumulation. Though clearly inferior to Oct-based radioimaging in most GEP-NET, MIBG achieves a remarkable rate of radioligand accumulation in functioning midgut enterochromaffin cell metastases (>80% of patients positive). These results may have implications for patient management and potentially for selection and performance of targeted therapy. 相似文献
4.
杨娅 Thomas Bartel Loredana Latina Guido Caspari 王新房 Raimund Erbel 《华中科技大学学报(医学英德文版)》2002,22(2):158-163
Coronary flow reserve (CFR) has been used toassess coronary microcirculation and epicardial coro-nary stenoses[1— 3 ] . CFR is defined as the ratio ofcoronary flow under maximal coronary vasodilatationto coronary flow under resting conditions[4 ] .Whenthe cross- sectional area of epicardial coronary arteriesis constant,coronary flow velocity (CFV) ratios areequal to volume flow ratios.The most common method used clinically formeasuring CFVR is intracoronary Doppler flow(ICD) analysis re… 相似文献
5.
Sylke Andreas Jörg Dirmaier Timo Harfst Stephan Kawski Uwe Koch Holger Schulz 《European psychiatry》2009,24(2):105-111
The aim of this study was to evaluate a case-mix system to classify inpatients with mental disorders in Germany by means of self-report and expert-rated instruments. The use of case-mix systems enhances the transparency of performance and cost structure and can thus improve the quality of mental health care. We analysed a consecutive sample of 1677 inpatients with mental disorders from 11 hospitals using regression tree analysis. The model assigns patients to 17 groups, accounting for 17% of the variance for duration of stay. Patients with eating disorders had a longer duration of stay than patients with anxiety disorder, duration of mental illness of less than 3–5 years, lower levels of interpersonal problems and higher occupational position. The results showed that besides diagnosis, variables such as duration of illness and interpersonal problems are important for classifying inpatients with mental disorders. The results of the study should be critically reviewed regarding the empirical results of other studies and the appropriateness of case group concepts for inpatients with mental disorders. 相似文献
6.
V. K. Sharma G. Tsivgoulis A. Y. Lao M. Flaster J. L. Frey M. D. Malkoff A. V. Alexandrov 《European journal of neurology》2007,14(2):237-240
Although common carotid artery (CCA) occlusions are rare, acute clinical presentations vary from mild to devastating strokes primarily due to tandem occlusions in the intracranial arteries. Three patients with acute CCA occlusions were treated with systemic tissue plasminogen activator (TPA). Blood pressures were kept at the upper limits allowed with TPA therapy with fluid balance and the 'head-down' position. Recanalization occurred in intracranial vessels only. Marked early neurological improvement occurred in two of three patients. CCA occlusions should not be considered contra-indication to systemic thrombolysis. 相似文献
7.
Xin He Jonathan M. Links Karen L. Gilland Benjamin M. W. Tsui Eric C. Frey 《Journal of nuclear cardiology》2006,13(3):345-353
BACKGROUND: The optimal projection data acquisition strategy for myocardial perfusion (MP) single photon emission computed tomography (SPECT) remains controversial. METHODS: We compared MP SPECT using 180 degrees and 360 degrees projection data obtained with the same acquisition time, reconstructed either with filtered back projection (FBP) or the iterative ordered-subsets expectation maximization (OS-EM) algorithm with various combinations of attenuation, detector response, and scatter compensation using mathematical observers and a myocardial defect detection task. We used Monte Carlo-simulated projection data from a population of 3-dimensional nurbs-based cardiac-torso (NCAT) phantoms with ranges of variability in patient anatomy, organ uptake, defect location, defect size, and noise level based on clinical data. Projection data from 180 degrees and 360 degrees acquisitions were generated by assuming the same acquisition time. After iterative or FBP reconstruction, standard postprocessing methods were applied. For each acquisition and reconstruction method, we optimized the number of iterations and cut-off frequency of the Butterworth filter using the Channelized Hotelling Observer methodology. The optimum set of parameters was that which gave the maximum area under the curve. RESULTS: For both acquisition protocols, OS-EM with compensations provided better performance than FBP or OS-EM without compensation. For FBP, the optimized 180 degrees acquisition provided a statistically significant increase in AUC as compared with optimized 360 degrees acquisition. For OS-EM, the AUCs for 180 degrees were slightly larger than for 360 degrees acquisitions when comparing images reconstructed with the same compensations. However, the differences were smaller and not statistically significant. CONCLUSION: With optimized reconstruction and filtering parameters, 180 degrees acquisition provided a statistically significant improvement over 360 degrees acquisition for FBP reconstruction. However, for OS-EM the differences were small and not statistically significant. 相似文献
8.
Isolde Hausser Wilhelm Doerr Rudolf Frey Adolf Ueberle 《Journal of cancer research and clinical oncology》1949,56(4-5):449-481
Ohne ZusammenfassungMit 24 Textabbildungen.Vorgetragen: 1. I. Hausser, Ultraschall-Arbeitstagung Erlangen, 3. 5. 49; s. Kongreßbericht. 2. W. Doerr, ebendort; infolge Erkrankung vertreten durch I. Hausser. 3. R. Frey, Deutscher Chirurgenkongreß in Frankfurt, 9. 6. 49. 相似文献
9.
On- and off-eye spherical aberration of soft contact lenses and consequent changes of effective lens power. 总被引:1,自引:0,他引:1
BACKGROUND: Soft contact lenses produce a significant level of spherical aberration affecting their power on-eye. A simple model assuming that a thin soft contact lens aligns to the cornea predicts that these effects are similar on-eye and off-eye. METHODS: The wavefront aberration for 17 eyes and 33 soft contact lenses on-eye was measured with a Shack-Hartmann wavefront sensor. The Zernike coefficients describing the on-eye spherical aberration of the soft contact lens were compared with off-eye ray-tracing results. Paraxial and effective lens power changes were determined. RESULTS: The model predicts the on-eye spherical aberration of soft contact lenses closely. The resulting power change for a +/- 7.00 D spherical soft contact lens is +/- 0.5 D for a 6-mm pupil diameter and +/- 0.1 D for a 3-mm pupil diameter. Power change is negligible for soft contact lenses corrected for off-eye spherical aberration. CONCLUSIONS: For thin soft contact lenses, the level of spherical aberration and the consequent power change is similar on-eye and off-eye. Soft contact lenses corrected for spherical aberration in air will be expected to be aberration-free on-eye and produce only negligibly small power changes. For soft contact lenses without aberration correction, for higher levels of ametropia and large pupils, the soft contact lens power should be determined with trial lenses with their power and p value similar to the prescribed lens. The benefit of soft contact lenses corrected for spherical aberration depends on the level of ocular spherical aberration. 相似文献
10.
Dr. Egon Frey 《Journal of neurology》1930,115(1-3):9-26
Zusammenfassung An einem genealogisch zusammenhängenden Menschenmaterial von über 100 Personen wurde bis jetzt an 55 ein streng dominant erbliches, von Geburt an bestehendes Kinnmuskelzittern nachgewiesen.Bei vielen Trägern dieses Merkmals ist dieses mit gewissen bahnenden Tätigkeiten verknüpft, denen ein gemeinsamer spezifischer Gemütszustand (Achtsamkeit) innezuwohnen scheint, zu dessen Darstellung das Phänomen unter Umständen dienen könnte.Verf. sieht in dieser Verknüpfung eine Verwandtschaft des Phänomens mit den Affektäußerungen und mimischen Ausdrucksbewegungen des Menschen.Nach einem am 28. III. 1930 in der Wiener Gesellschaft der Ärzte gehaltenen Vortrage, wobei sieben Träger des Phänomens (Nr. 26, 28, 31, 34, 47, 50 und 52 des Stammbaums) vorgeführt wurden.Das Geburtsjahr wurde darum überall mitangeführt, weil es eine Hypothese, die sog. H. Swobodasche Siebenjahrlehre gibt, die den Einfluß eines Zeitfaktors in Form einer meist siebenjährigen Periodizität auf das erbliche Geschehen behauptet. Wie man sieht, könnte mau bei weniger ausführlichem Studium durch einige Beispiele (3, 11, 40!) versucht sein, auch aus dem vorliegenden Stammbaum ein solches Gesetz zu konstruieren. Genauerer Hinblick gibt aber schlagende Gegenbeispiele. Denn wie will H. Swoboda das unmittelbare Alternieren von Merkmalträgern und Merkmalfreien mit seiner Theorie in Einklang bringen? Z. B. Franz Sch. (4) ist tatsächlich 21, also dreimal sieben Jahre nach seiner Mutter Barbara (2) geboren. Der Einfluß dieses Siebenjahres muß nun aber schon im nächsten Jahr nach Swoboda erloschen sein, da ja der 1847 geborene Josef das KMZ. nicht bekam. Dann müßte aber das nächste Siebenjahr (1853) einen viel breiteren Einflußbereich (volle 5 Jahre) gehabt haben, da ihm sowohl Johanna (1850) wie Anton (1855) ihr KMZ. verdanken sollten. Das nächste Siebenjahr aber blieb überhaupt wirkungslos, denn Josefa (1860) ist frei von KMZ. Nun, was für das eine Siebenjahr recht ist, muß für das andere billig sein. Dies nur ein Beispiel für viele, das genugsam zeigt, wie trügerisch solches Spiel mit Zahlen ist. Und es ist immerhin bedenklich, wenn eine Lehre, die sich bis zu eugenetisehen Ratschlägen an hereditär belastete Eltern versteigt (!), an einem Erbmerkmal von so ungeheurer Durchschlagskraft, wie es das hier besprochene ist, ihre Gültigkeit nicht zeigen kann. 相似文献