ABSTRACT Subcellular structures are mainly responsible for light scattering in tissue. Since thes... more ABSTRACT Subcellular structures are mainly responsible for light scattering in tissue. Since these structures change their outer shape during hypoxia, backscattered light intensity should be useful in monitoring of tissue in hypoxic or ischemic situations. In a new model of isolated perfused pig heart we investigated the relation between three-dimensional functional structures caused by tissue light scattering and the perfusion pressure during reoxygenation after hypoxia. By use of EMPHO-Oxyscan we could see that there is a clear relation between the perfusion pressure and the level of 3D structures. At very low perfusion pressures there is a delay in recovery of myocardium. Increase in perfusion pressure accelerates the recovery. With functional 3D images created by use of EMPHO-Oxyscan, we now have an instrument for depicting these processes. This technique will be useful in clinical monitoring in cardiac surgery, intraoperative as well as postoperative.
ABSTRACT Light scattering in tissue of mammals and humans is affected by subcellular structures. ... more ABSTRACT Light scattering in tissue of mammals and humans is affected by subcellular structures. Since these structures correlate well with the status of cells and tissue, light scattering seems to be ideal for monitoring of functional tissue state. By use of EMPHO SSK Oxyscan we investigated functional parameters in a novel kind of isolated perfused pig heart model. In this perfusion model we use organs obtained by the local slaughterhouse that are reanimated at our institute by application of a heart-lung machine. By creating 3D-images of tissue scattering we found an interesting relation between anatomical structures of myocardium and the 3D-images. Additionally, we detected coherence between backscattered light intensity and functional tissue status. Furthermore, we got a sight into the redox state of cytochrome aa3, b and c by creating difference spectra. We believe that this new kind of tissue imaging method will give us the opportunity to get new insights into myocardial function.
Living tissue of mammals contains a large amount of subcellular particles like mitochondria that ... more Living tissue of mammals contains a large amount of subcellular particles like mitochondria that are involved in light scattering. Since these particles correlate in a certain way with the functional status of cells, light scattering may be useful for monitoring of functional tissue state. With EMPHO SSK Oxyscan we investigated functional parameters in a new kind of isolated perfused pig heart model. In this perfusion model we use organs obtained from the abattoir that are reperfused by use of a heart-lung machine. By creating 3D images of tissue light scattering we found an interesting relation between morphological structures of myocardium and the patterns of the 3D images. Additionally, we created 3D images of myoglobin oxygenation. Furthermore, we got spectra showing the redox state of cytochromes. We believe that this new kind of tissue imaging method will give us the opportunity to get new insights into myocardial function.
ABSTRACT Imaging in the microcosm of capillaries and cells in intact tissues opened new fields fo... more ABSTRACT Imaging in the microcosm of capillaries and cells in intact tissues opened new fields for research and patient monitoring. The experimental separation of scattering ((mu) s) and absorption ((mu) a) in organs can be improved drastically by visualization of subcellular structures. Improved evaluation techniques which apply matrices for storage of determined optical signals are very favorable.
Objective: To define benchmark values for adult-to-adult living-donor liver transplantation (LDLT... more Objective: To define benchmark values for adult-to-adult living-donor liver transplantation (LDLT). Background: LDLT utilizes living-donor hemiliver grafts to expand the donor pool and reduce waitlist mortality. Although references have been established for donor hepatectomy, no such information exists for recipients to enable conclusive quality and comparative assessments. Methods: Patients undergoing LDLT were analyzed in 15 high-volume centers (≥10 cases/year) from 3 continents over 5 years (2016–2020), with a minimum follow-up of 1 year. Benchmark criteria included a Model for End-stage Liver Disease ≤20, no portal vein thrombosis, no previous major abdominal surgery, no renal replacement therapy, no acute liver failure, and no intensive care unit admission. Benchmark cutoffs were derived from the 75th percentile of all centers’ medians. Results: Of 3636 patients, 1864 (51%) qualified as benchmark cases. Benchmark cutoffs, including posttransplant dialysis (≤4%), primary nonfunction (≤0.9%), nonanastomotic strictures (≤0.2%), graft loss (≤7.7%), and redo-liver transplantation (LT) (≤3.6%), at 1-year were below the deceased donor LT benchmarks. Bile leak (≤12.4%), hepatic artery thrombosis (≤5.1%), and Comprehensive Complication Index (CCI®) (≤56) were above the deceased donor LT benchmarks, whereas mortality (≤9.1%) was comparable. The right hemiliver graft, compared with the left, was associated with a lower CCI® score (34 vs 21, P < 0.001). Preservation of the middle hepatic vein with the right hemiliver graft had no impact neither on the recipient nor on the donor outcome. Asian centers outperformed other centers with CCI® score (21 vs 47, P < 0.001), graft loss (3.0% vs 6.5%, P = 0.002), and redo-LT rates (1.0% vs 2.5%, P = 0.029). In contrast, non-benchmark low-volume centers displayed inferior outcomes, such as bile leak (15.2%), hepatic artery thrombosis (15.2%), or redo-LT (6.5%). Conclusions: Benchmark LDLT offers a valuable alternative to reduce waitlist mortality. Exchange of expertise, public awareness, and centralization policy are, however, mandatory to achieve benchmark outcomes worldwide.
Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2017
Our program routinely used fluorodeoxyglucose-positron emission tomography/computed tomography as... more Our program routinely used fluorodeoxyglucose-positron emission tomography/computed tomography as part of the liver transplant evaluation of patients with hepatocellular carcinoma. The aim of this study was to evaluate the role of this imaging modality in the pretransplant work-up. This was a retrospective chart review of our liver transplant database from January 2011 to December 2014 for all patients with hepatocellular carcinoma who underwent a liver transplant. Collected data included age, sex, cause of liver disease, imaging modality, fluorodeoxyglucose-positron emission tomography/computed tomography results, explant tissue analysis, type of transplant, and transplant outcome. During the study period, 275 liver transplants were performed. Fifty-three patients had hepatocellular carcinoma; 41 underwent fluorodeoxyglucose-positron emission tomography/computed tomography. Twenty-nine patients underwent living-donor liver transplant, and 12 patients underwent deceased-donor liver ...
* Available as a photocopy reprint only. Allow two weeks reprinting time plus standard delivery t... more * Available as a photocopy reprint only. Allow two weeks reprinting time plus standard delivery time. No discounts or returns apply. ... Standard delivery in the US is 7 to 10 business days and outside the US delivery is 4 to 6 weeks or longer. For further details, please see shipping policy. ... Listed below are the papers found in this volume. Click the paper title to view an abstract or to order an individual paper.
Einleitung: Aufgrund der Organknappheit wird die Verteilung von Organen an Patienten mit potentie... more Einleitung: Aufgrund der Organknappheit wird die Verteilung von Organen an Patienten mit potentiell schlechtem postoperativem Überleben kontrovers diskutiert. Wir untersuchten den Einfluss von unmittelbar präoperativer Beatmungspflichtigkeit auf das Outcome der Lebertransplantation in einer[for full text, please go to the a.m. URL]
Advances in Experimental Medicine and Biology, 1998
Processes like angiogenesis are critically dependent on local oxygen supply. It is known that hyp... more Processes like angiogenesis are critically dependent on local oxygen supply. It is known that hypoxia induces an up-regulation of the vascular endothelial growth factor (VEGF, Giaccia et al. 1995, Goldberg and Schneider 1994, Hlatky et al. 1995, Shweiki et al. 1992) gene, increased synthesis of the peptide and an increased proliferation of endothelial cells. Also tumour growth is associated with angiogenesis (Bikfalvi 1995) and it has been shown that different tumour cells increase the VEGF production during hypoxia.
Severe hyponatremia has been described after elective surgery with subsequent permanent brain dam... more Severe hyponatremia has been described after elective surgery with subsequent permanent brain damage. Other authors, however, have noted that morbidity and mortality rates of severe hyponatremia have been greatly overestimated. We retrospectively examined 19 patients (8 male, 11 female) who developed severe hyponatremia (100 to 124 mmol/liter) after transsphenoidal surgery for pituitary adenomas. Eight patients had hormonally inactive adenomas, 5 ACTH-secreting adenomas, 2 GH-secreting adenomas and 4 prolactin-secreting adenomas. The mean age of the patients was 47.5 years, with a range from 16 to 71 years. The mean preoperative serum sodium level was 137.8 mmol/liter. The timing of hyponatremia showed two different patterns. Five patients developed early postoperative hyponatremia (mean 114.0 mmol/liter +/- 4.85) and 14 patients showed the lowest mean serum level one week after surgery (118.1 mmol/liter +/- 6.86). Patients with early hyponatremia had fewer and less severe symptoms ...
ABSTRACT Subcellular structures are mainly responsible for light scattering in tissue. Since thes... more ABSTRACT Subcellular structures are mainly responsible for light scattering in tissue. Since these structures change their outer shape during hypoxia, backscattered light intensity should be useful in monitoring of tissue in hypoxic or ischemic situations. In a new model of isolated perfused pig heart we investigated the relation between three-dimensional functional structures caused by tissue light scattering and the perfusion pressure during reoxygenation after hypoxia. By use of EMPHO-Oxyscan we could see that there is a clear relation between the perfusion pressure and the level of 3D structures. At very low perfusion pressures there is a delay in recovery of myocardium. Increase in perfusion pressure accelerates the recovery. With functional 3D images created by use of EMPHO-Oxyscan, we now have an instrument for depicting these processes. This technique will be useful in clinical monitoring in cardiac surgery, intraoperative as well as postoperative.
ABSTRACT Light scattering in tissue of mammals and humans is affected by subcellular structures. ... more ABSTRACT Light scattering in tissue of mammals and humans is affected by subcellular structures. Since these structures correlate well with the status of cells and tissue, light scattering seems to be ideal for monitoring of functional tissue state. By use of EMPHO SSK Oxyscan we investigated functional parameters in a novel kind of isolated perfused pig heart model. In this perfusion model we use organs obtained by the local slaughterhouse that are reanimated at our institute by application of a heart-lung machine. By creating 3D-images of tissue scattering we found an interesting relation between anatomical structures of myocardium and the 3D-images. Additionally, we detected coherence between backscattered light intensity and functional tissue status. Furthermore, we got a sight into the redox state of cytochrome aa3, b and c by creating difference spectra. We believe that this new kind of tissue imaging method will give us the opportunity to get new insights into myocardial function.
Living tissue of mammals contains a large amount of subcellular particles like mitochondria that ... more Living tissue of mammals contains a large amount of subcellular particles like mitochondria that are involved in light scattering. Since these particles correlate in a certain way with the functional status of cells, light scattering may be useful for monitoring of functional tissue state. With EMPHO SSK Oxyscan we investigated functional parameters in a new kind of isolated perfused pig heart model. In this perfusion model we use organs obtained from the abattoir that are reperfused by use of a heart-lung machine. By creating 3D images of tissue light scattering we found an interesting relation between morphological structures of myocardium and the patterns of the 3D images. Additionally, we created 3D images of myoglobin oxygenation. Furthermore, we got spectra showing the redox state of cytochromes. We believe that this new kind of tissue imaging method will give us the opportunity to get new insights into myocardial function.
ABSTRACT Imaging in the microcosm of capillaries and cells in intact tissues opened new fields fo... more ABSTRACT Imaging in the microcosm of capillaries and cells in intact tissues opened new fields for research and patient monitoring. The experimental separation of scattering ((mu) s) and absorption ((mu) a) in organs can be improved drastically by visualization of subcellular structures. Improved evaluation techniques which apply matrices for storage of determined optical signals are very favorable.
Objective: To define benchmark values for adult-to-adult living-donor liver transplantation (LDLT... more Objective: To define benchmark values for adult-to-adult living-donor liver transplantation (LDLT). Background: LDLT utilizes living-donor hemiliver grafts to expand the donor pool and reduce waitlist mortality. Although references have been established for donor hepatectomy, no such information exists for recipients to enable conclusive quality and comparative assessments. Methods: Patients undergoing LDLT were analyzed in 15 high-volume centers (≥10 cases/year) from 3 continents over 5 years (2016–2020), with a minimum follow-up of 1 year. Benchmark criteria included a Model for End-stage Liver Disease ≤20, no portal vein thrombosis, no previous major abdominal surgery, no renal replacement therapy, no acute liver failure, and no intensive care unit admission. Benchmark cutoffs were derived from the 75th percentile of all centers’ medians. Results: Of 3636 patients, 1864 (51%) qualified as benchmark cases. Benchmark cutoffs, including posttransplant dialysis (≤4%), primary nonfunction (≤0.9%), nonanastomotic strictures (≤0.2%), graft loss (≤7.7%), and redo-liver transplantation (LT) (≤3.6%), at 1-year were below the deceased donor LT benchmarks. Bile leak (≤12.4%), hepatic artery thrombosis (≤5.1%), and Comprehensive Complication Index (CCI®) (≤56) were above the deceased donor LT benchmarks, whereas mortality (≤9.1%) was comparable. The right hemiliver graft, compared with the left, was associated with a lower CCI® score (34 vs 21, P < 0.001). Preservation of the middle hepatic vein with the right hemiliver graft had no impact neither on the recipient nor on the donor outcome. Asian centers outperformed other centers with CCI® score (21 vs 47, P < 0.001), graft loss (3.0% vs 6.5%, P = 0.002), and redo-LT rates (1.0% vs 2.5%, P = 0.029). In contrast, non-benchmark low-volume centers displayed inferior outcomes, such as bile leak (15.2%), hepatic artery thrombosis (15.2%), or redo-LT (6.5%). Conclusions: Benchmark LDLT offers a valuable alternative to reduce waitlist mortality. Exchange of expertise, public awareness, and centralization policy are, however, mandatory to achieve benchmark outcomes worldwide.
Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2017
Our program routinely used fluorodeoxyglucose-positron emission tomography/computed tomography as... more Our program routinely used fluorodeoxyglucose-positron emission tomography/computed tomography as part of the liver transplant evaluation of patients with hepatocellular carcinoma. The aim of this study was to evaluate the role of this imaging modality in the pretransplant work-up. This was a retrospective chart review of our liver transplant database from January 2011 to December 2014 for all patients with hepatocellular carcinoma who underwent a liver transplant. Collected data included age, sex, cause of liver disease, imaging modality, fluorodeoxyglucose-positron emission tomography/computed tomography results, explant tissue analysis, type of transplant, and transplant outcome. During the study period, 275 liver transplants were performed. Fifty-three patients had hepatocellular carcinoma; 41 underwent fluorodeoxyglucose-positron emission tomography/computed tomography. Twenty-nine patients underwent living-donor liver transplant, and 12 patients underwent deceased-donor liver ...
* Available as a photocopy reprint only. Allow two weeks reprinting time plus standard delivery t... more * Available as a photocopy reprint only. Allow two weeks reprinting time plus standard delivery time. No discounts or returns apply. ... Standard delivery in the US is 7 to 10 business days and outside the US delivery is 4 to 6 weeks or longer. For further details, please see shipping policy. ... Listed below are the papers found in this volume. Click the paper title to view an abstract or to order an individual paper.
Einleitung: Aufgrund der Organknappheit wird die Verteilung von Organen an Patienten mit potentie... more Einleitung: Aufgrund der Organknappheit wird die Verteilung von Organen an Patienten mit potentiell schlechtem postoperativem Überleben kontrovers diskutiert. Wir untersuchten den Einfluss von unmittelbar präoperativer Beatmungspflichtigkeit auf das Outcome der Lebertransplantation in einer[for full text, please go to the a.m. URL]
Advances in Experimental Medicine and Biology, 1998
Processes like angiogenesis are critically dependent on local oxygen supply. It is known that hyp... more Processes like angiogenesis are critically dependent on local oxygen supply. It is known that hypoxia induces an up-regulation of the vascular endothelial growth factor (VEGF, Giaccia et al. 1995, Goldberg and Schneider 1994, Hlatky et al. 1995, Shweiki et al. 1992) gene, increased synthesis of the peptide and an increased proliferation of endothelial cells. Also tumour growth is associated with angiogenesis (Bikfalvi 1995) and it has been shown that different tumour cells increase the VEGF production during hypoxia.
Severe hyponatremia has been described after elective surgery with subsequent permanent brain dam... more Severe hyponatremia has been described after elective surgery with subsequent permanent brain damage. Other authors, however, have noted that morbidity and mortality rates of severe hyponatremia have been greatly overestimated. We retrospectively examined 19 patients (8 male, 11 female) who developed severe hyponatremia (100 to 124 mmol/liter) after transsphenoidal surgery for pituitary adenomas. Eight patients had hormonally inactive adenomas, 5 ACTH-secreting adenomas, 2 GH-secreting adenomas and 4 prolactin-secreting adenomas. The mean age of the patients was 47.5 years, with a range from 16 to 71 years. The mean preoperative serum sodium level was 137.8 mmol/liter. The timing of hyponatremia showed two different patterns. Five patients developed early postoperative hyponatremia (mean 114.0 mmol/liter +/- 4.85) and 14 patients showed the lowest mean serum level one week after surgery (118.1 mmol/liter +/- 6.86). Patients with early hyponatremia had fewer and less severe symptoms ...
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