Zusammenfassung GRUNDLAGEN: Wir untersuchten die Sicherheit und Wirksamkeit eines neuen endovask... more Zusammenfassung GRUNDLAGEN: Wir untersuchten die Sicherheit und Wirksamkeit eines neuen endovaskulären Radiofrequenzkatheters (VesCoag) für den Arterienverschluss beim Management von Lebertumoren. METHODIK: Die Patienten hatten einen nicht resektablen primären oder sekundären Lebertumor. Der primäre Endpunkt war, ob VesCoag in das Zielgefäß eingebracht werden konnte, der sekundäre Endpunkt, ob es zu einem Angiographie-geprüften Verschluss des Gefäßes kam. ERGEBNISSE: VesCoag wurde bei 13 Patienten
Recent advances in regenerative medicine, including hematopoietic stem cell (HSC) transplantation... more Recent advances in regenerative medicine, including hematopoietic stem cell (HSC) transplantation, have brought hope for patients with severe alcoholic liver cirrhosis (ALC). The aim of this study was to assess the safety and efficacy of administering autologous expanded mobilized adult progenitor CD34+ cells into the hepatic artery of ALC patients and the potential improvement in the liver function. Nine patients with biopsy-proven ALC, who had abstained from alcohol for at least 6 months, were recruited into the study. Following granulocyte colony-stimulating factor (G-CSF) mobilization and leukapheresis, the autologous CD34+ cells were expanded in vitro and injected into the hepatic artery. All patients were monitored for side effects, toxicities, and changes in the clinical, hematological, and biochemical parameters. On average, a five-fold expansion in cell number was achieved in vitro, with a mean total nucleated cell count (TNCC) of 2.3 x 10(8) pre infusion. All patients tole...
The purpose of this study was to present a radiofrequency (RF) endovascular occlusion device (ie,... more The purpose of this study was to present a radiofrequency (RF) endovascular occlusion device (ie, Habib VesCoag Catheter; EMcision Ltd, London, UK) and to evaluate safety and efficacy of the device for complete occlusion of normal porcine vessels. The study included 20 pigs. In each pig, a segmental branch of the right hepatic artery, a branch of the splenic artery, and a branch of one of the renal arteries were catheterized. A single or multiple applications of RF energy were performed until vessel occlusion was achieved. Fifteen days later, angiography was repeated to assess vessel patency. The vessels were then excised for pathological analysis. Vessels 2.5 to 6 mm in diameter were treated. Complete occlusion with a single attempt was achieved using a mean amount of energy of 110.67 J in vessels 2.5 to 3 mm, 111.67 J in vessels 3.5 to 4 mm, and 116.63 J in vessels 5 to 6 mm in diameter and was confirmed by angiography at the 15-day follow-up. Vascular occlusion can be effectively and safely achieved by endovascular application of RF energy to normal porcine arteries using the Habib VesCoag catheter.
The aim of the study was to evaluate the diagnostic accuracy of Color Doppler US, CT Angiography ... more The aim of the study was to evaluate the diagnostic accuracy of Color Doppler US, CT Angiography (CTA), and GD-enhanced MR Angiography (MRA) compared with digital subtraction angiography (DSA) for the detection of renal artery stenosis in patients with clinically suspected renovascular hypertension. Fifty-eight patients with suspected renovascular hypertension were enrolled in the study. All patients underwent Color Doppler US, CTA and GD-enhanced MRA. DSA was the gold standard method for the number of renal arteries, existence and degree of stenosis, or evidence of fibromuscular dysplasia. DSA depicted 132 renal arteries, 16 stenoses, and 4 arteries with fibromuscular dysplasia. Color Doppler US failed to detect 1 main and 14 polar arteries. CTA depicted all main renal arteries and 7/16 polar arteries, but failed to detect stenosis in two accessory vessels. Likewise, MRA did not detect stenotic accessory renal arteries, depicted 9/16 polar renal arteries, but missed two main renal arteries. All methods depicted the four main renal arteries with fibromuscular dysplasia. The overall sensitivity, specificity, and positive and negative predictive accuracy were 75%, 89.6%, 60% and 94.6%, respectively, for color Doppler US; 94%, 93%, 71%, and 99%, respectively, for CTA; and 90%, 94.1%, 75%, and 98%, respectively, for GD-enhanced MRA. CTA and GD-enhanced MRA have comparable and satisfactory results with respect to the negative predictive accuracy of the suspected renal artery stenosis. The concept of an imaging algorithm including US as screening test when appropriate and CTA or MRA as the second step-procedure is suggested. Therefore, DSA may be reserved for cases with major discrepancies or therapeutic interventions.
Laparoscopic sleeve gastrectomy (LSG) is a relatively new bariatric procedure, and data regarding... more Laparoscopic sleeve gastrectomy (LSG) is a relatively new bariatric procedure, and data regarding the learning curve are scarce. The aim of this study is to assess how the procedure can be safely implanted in a newly established bariatric unit and to define the learning curve. Proctorship and mentorship in bariatric surgery were attended by two surgeons who were previously experienced in advanced laparoscopic surgery. The first consecutive 102 patients who underwent LSG in our newly established bariatric center were included. Patients were divided into three groups of 34 (groups 1, 2, and 3) according to case sequence. Data on demographics, operative time, conversion rate, hospital stay, morbidity, mortality, and excess weight loss (EWL) over time were compared between the groups. The operative time was significantly lower in groups 2 (p = 0.016) and 3 (p = 0.003) compared to group 1. The learning curve was flat up to the 68th case. A significant decrease in hospital stay was noted for group 3 compared to groups 1 (p < 0.001) and 2 (p = 0.002). The conversion rate, mortality and morbidity rates, and EWL did not differ significantly between the groups. Mortality was 0.98% and procedure-related morbidity was 7.8%. LSG can be safely and efficiently performed in a newly established bariatric center following a mentorship procedure. Proficiency seems to require 68 cases. The operative time and hospital stay may significantly decrease with experience early in the learning curve, as opposed to mortality and morbidity rates, conversion rate, and EWL.
Journal of Laparoendoscopic & Advanced Surgical Techniques, 2010
Hemorrhage control in severe splenic and hepatic injuries remains a challenge, despite recent imp... more Hemorrhage control in severe splenic and hepatic injuries remains a challenge, despite recent improvements in equipment technology. Radiofrequency (RF) energy-assisted surgery for the spleen and liver has been recently reported; however, the technique has not gained wide acceptance, mainly due to surgeons' unfamiliarity with the technique and the risk of complications caused by uncontrolled disseminated energy. In this study, the safety and efficacy of the Habib 4X (AngioDynamics, Latham, NY), a hand-held bipolar RF energy device, was evaluated in a porcine trauma model. Five white male Landrace pigs were included in the study. Multiple stab wounds were inflicted to the splenic and hepatic parenchyma, both centrally and peripherally. Hemostasis was achieved by using the Habib 4X RF bipolar device. The pigs were humanely sacrificed 6 weeks postoperatively, and histology of the ablated spleen and liver was evaluated. Hemorrhage was successfully controlled at all bleeding sites, using appropriate RF generator settings. The splenic artery and vein, as well as the hepatic veins, were successfully ligated using the device. No complications were noted immediately postoperatively or 6 weeks following the procedure. The bipolar Habib 4X device delivers RF energy that can achieve hemostasis of the injured splenic and hepatic parenchyma. The method is feasible and safe. Clinical studies are warranted to assess short- and long-term results of this promising technique and compare it to the gold standards.
To develop a new rabbit model of arterial stenosis using endovascular radiofrequency (RF) energy.... more To develop a new rabbit model of arterial stenosis using endovascular radiofrequency (RF) energy. Ten rabbits were used for multiple endovascular RF applications to the aorta and left common carotid artery through the Habib™ VesCoag™ catheter. Angiography and color Doppler ultrasound were used to assess vessel patency immediately following the procedure and six weeks later. One rabbit was sacrificed following the procedure for histopathologic analysis of the vessel wall. Two rabbits died of aortic and carotid rupture, respectively, immediately after the procedure. The remaining seven rabbits were sacrificed after six-week follow-up for histopathological analysis. Optimal RF generator settings to induce significant arterial stenosis (>50%) without complications were standardized at 24-26 watts (W) for 1.5 min for the aorta and 6 W for 1 min for the common carotid artery. The six-week follow-up showed permanent results in all surviving rabbits. Histopathology revealed intima and medial smooth muscle layer necrosis. We have developed a novel rabbit model of arterial stenosis using endovascular RF energy. Our model is fast, safe, inexpensive, and reproducible. It would be useful for experimental investigations and new therapeutic devices.
To investigate the use of a new endovascular radiofrequency (RF) device, the Habib™ VesCoag™ Cath... more To investigate the use of a new endovascular radiofrequency (RF) device, the Habib™ VesCoag™ Catheter, to induce vascular remodeling and dilatation of arterial stenosis in a rabbit model. RF was used to induce arterial stenosis in 10 rabbits and this was confirmed by angiography and color Doppler ultrasound. Two groups of five animals were then subjected to (1) balloon dilatation of the stenosis (intervention group), (2) no intervention (control group). Two rabbits from each group were sacrificed following the procedures to investigate vessel histopathology. At six weeks, the remaining six rabbits underwent follow-up angiogram and color Doppler ultrasound to assess vessel patency. They were then sacrificed and the vessels prepared for histopathological analysis. Three-dimensional images with confocal microscopy of the arterial lumen were also acquired. In the intervention group, stenosis was reversed and patency confirmed by angiography and color Doppler ultrasound six weeks later in all surviving rabbits. Histopathology revealed degenerative changes of elastic fibers, focal losses of elastica lamella, disorganization of myocytes and extensive hyalinization of the tunica adventitia. Focal elastin changes of the arterial elastic lamella were also shown by three-dimensional confocal microscopy images. We have developed a novel endovascular RF catheter that can be safely and effectively used to induce vascular remodeling and dilatation of arterial stenosis in an experimental rabbit model.
We validated the association of simple renal cysts with abdominal aortic aneurysm and other cardi... more We validated the association of simple renal cysts with abdominal aortic aneurysm and other cardiovascular factors and assessed simple renal cysts' impact on renal function before and after endovascular abdominal aortic aneurysm repair. A retrospective analysis of prospectively collected data was conducted. Computed tomography angiograms of 100 consecutive male patients with abdominal aortic aneurysm who underwent endovascular abdominal aortic aneurysm repair (Group 1) were reviewed and compared with 100 computed tomography angiogram of aged-matched male patients without abdominal aortic aneurysm (Group 2). Patients' demographic data, risk factors, abdominal aortic aneurysm diameter, the presence of simple renal cyst and laboratory tests were recorded. No difference was observed between the two groups in respect to other cardiovascular risk factors except hyperlipidemia with higher prevalence in Group 1 (p < 0.05). Presence of simple renal cysts was independently associated with age (p < 0.05) and abdominal aortic aneurysm (p = 0.0157). There was no correlation between simple renal cysts and abdominal aortic aneurysm size or pre-operative creatinine and urea levels. No difference was observed in post-operative creatinine and urea levels either immediately after endovascular abdominal aortic aneurysm repair or in 12-month follow-up. In male patients, the presence of simple renal cysts is associated with abdominal aortic aneurysm and is increasing with age. However, their presence is neither associated with impaired renal function pre-endovascular abdominal aortic aneurysm repair and post-endovascular abdominal aortic aneurysm repair nor after 12-month follow-up.
Zusammenfassung GRUNDLAGEN: Wir untersuchten die Sicherheit und Wirksamkeit eines neuen endovask... more Zusammenfassung GRUNDLAGEN: Wir untersuchten die Sicherheit und Wirksamkeit eines neuen endovaskulären Radiofrequenzkatheters (VesCoag) für den Arterienverschluss beim Management von Lebertumoren. METHODIK: Die Patienten hatten einen nicht resektablen primären oder sekundären Lebertumor. Der primäre Endpunkt war, ob VesCoag in das Zielgefäß eingebracht werden konnte, der sekundäre Endpunkt, ob es zu einem Angiographie-geprüften Verschluss des Gefäßes kam. ERGEBNISSE: VesCoag wurde bei 13 Patienten
Recent advances in regenerative medicine, including hematopoietic stem cell (HSC) transplantation... more Recent advances in regenerative medicine, including hematopoietic stem cell (HSC) transplantation, have brought hope for patients with severe alcoholic liver cirrhosis (ALC). The aim of this study was to assess the safety and efficacy of administering autologous expanded mobilized adult progenitor CD34+ cells into the hepatic artery of ALC patients and the potential improvement in the liver function. Nine patients with biopsy-proven ALC, who had abstained from alcohol for at least 6 months, were recruited into the study. Following granulocyte colony-stimulating factor (G-CSF) mobilization and leukapheresis, the autologous CD34+ cells were expanded in vitro and injected into the hepatic artery. All patients were monitored for side effects, toxicities, and changes in the clinical, hematological, and biochemical parameters. On average, a five-fold expansion in cell number was achieved in vitro, with a mean total nucleated cell count (TNCC) of 2.3 x 10(8) pre infusion. All patients tole...
The purpose of this study was to present a radiofrequency (RF) endovascular occlusion device (ie,... more The purpose of this study was to present a radiofrequency (RF) endovascular occlusion device (ie, Habib VesCoag Catheter; EMcision Ltd, London, UK) and to evaluate safety and efficacy of the device for complete occlusion of normal porcine vessels. The study included 20 pigs. In each pig, a segmental branch of the right hepatic artery, a branch of the splenic artery, and a branch of one of the renal arteries were catheterized. A single or multiple applications of RF energy were performed until vessel occlusion was achieved. Fifteen days later, angiography was repeated to assess vessel patency. The vessels were then excised for pathological analysis. Vessels 2.5 to 6 mm in diameter were treated. Complete occlusion with a single attempt was achieved using a mean amount of energy of 110.67 J in vessels 2.5 to 3 mm, 111.67 J in vessels 3.5 to 4 mm, and 116.63 J in vessels 5 to 6 mm in diameter and was confirmed by angiography at the 15-day follow-up. Vascular occlusion can be effectively and safely achieved by endovascular application of RF energy to normal porcine arteries using the Habib VesCoag catheter.
The aim of the study was to evaluate the diagnostic accuracy of Color Doppler US, CT Angiography ... more The aim of the study was to evaluate the diagnostic accuracy of Color Doppler US, CT Angiography (CTA), and GD-enhanced MR Angiography (MRA) compared with digital subtraction angiography (DSA) for the detection of renal artery stenosis in patients with clinically suspected renovascular hypertension. Fifty-eight patients with suspected renovascular hypertension were enrolled in the study. All patients underwent Color Doppler US, CTA and GD-enhanced MRA. DSA was the gold standard method for the number of renal arteries, existence and degree of stenosis, or evidence of fibromuscular dysplasia. DSA depicted 132 renal arteries, 16 stenoses, and 4 arteries with fibromuscular dysplasia. Color Doppler US failed to detect 1 main and 14 polar arteries. CTA depicted all main renal arteries and 7/16 polar arteries, but failed to detect stenosis in two accessory vessels. Likewise, MRA did not detect stenotic accessory renal arteries, depicted 9/16 polar renal arteries, but missed two main renal arteries. All methods depicted the four main renal arteries with fibromuscular dysplasia. The overall sensitivity, specificity, and positive and negative predictive accuracy were 75%, 89.6%, 60% and 94.6%, respectively, for color Doppler US; 94%, 93%, 71%, and 99%, respectively, for CTA; and 90%, 94.1%, 75%, and 98%, respectively, for GD-enhanced MRA. CTA and GD-enhanced MRA have comparable and satisfactory results with respect to the negative predictive accuracy of the suspected renal artery stenosis. The concept of an imaging algorithm including US as screening test when appropriate and CTA or MRA as the second step-procedure is suggested. Therefore, DSA may be reserved for cases with major discrepancies or therapeutic interventions.
Laparoscopic sleeve gastrectomy (LSG) is a relatively new bariatric procedure, and data regarding... more Laparoscopic sleeve gastrectomy (LSG) is a relatively new bariatric procedure, and data regarding the learning curve are scarce. The aim of this study is to assess how the procedure can be safely implanted in a newly established bariatric unit and to define the learning curve. Proctorship and mentorship in bariatric surgery were attended by two surgeons who were previously experienced in advanced laparoscopic surgery. The first consecutive 102 patients who underwent LSG in our newly established bariatric center were included. Patients were divided into three groups of 34 (groups 1, 2, and 3) according to case sequence. Data on demographics, operative time, conversion rate, hospital stay, morbidity, mortality, and excess weight loss (EWL) over time were compared between the groups. The operative time was significantly lower in groups 2 (p = 0.016) and 3 (p = 0.003) compared to group 1. The learning curve was flat up to the 68th case. A significant decrease in hospital stay was noted for group 3 compared to groups 1 (p < 0.001) and 2 (p = 0.002). The conversion rate, mortality and morbidity rates, and EWL did not differ significantly between the groups. Mortality was 0.98% and procedure-related morbidity was 7.8%. LSG can be safely and efficiently performed in a newly established bariatric center following a mentorship procedure. Proficiency seems to require 68 cases. The operative time and hospital stay may significantly decrease with experience early in the learning curve, as opposed to mortality and morbidity rates, conversion rate, and EWL.
Journal of Laparoendoscopic & Advanced Surgical Techniques, 2010
Hemorrhage control in severe splenic and hepatic injuries remains a challenge, despite recent imp... more Hemorrhage control in severe splenic and hepatic injuries remains a challenge, despite recent improvements in equipment technology. Radiofrequency (RF) energy-assisted surgery for the spleen and liver has been recently reported; however, the technique has not gained wide acceptance, mainly due to surgeons' unfamiliarity with the technique and the risk of complications caused by uncontrolled disseminated energy. In this study, the safety and efficacy of the Habib 4X (AngioDynamics, Latham, NY), a hand-held bipolar RF energy device, was evaluated in a porcine trauma model. Five white male Landrace pigs were included in the study. Multiple stab wounds were inflicted to the splenic and hepatic parenchyma, both centrally and peripherally. Hemostasis was achieved by using the Habib 4X RF bipolar device. The pigs were humanely sacrificed 6 weeks postoperatively, and histology of the ablated spleen and liver was evaluated. Hemorrhage was successfully controlled at all bleeding sites, using appropriate RF generator settings. The splenic artery and vein, as well as the hepatic veins, were successfully ligated using the device. No complications were noted immediately postoperatively or 6 weeks following the procedure. The bipolar Habib 4X device delivers RF energy that can achieve hemostasis of the injured splenic and hepatic parenchyma. The method is feasible and safe. Clinical studies are warranted to assess short- and long-term results of this promising technique and compare it to the gold standards.
To develop a new rabbit model of arterial stenosis using endovascular radiofrequency (RF) energy.... more To develop a new rabbit model of arterial stenosis using endovascular radiofrequency (RF) energy. Ten rabbits were used for multiple endovascular RF applications to the aorta and left common carotid artery through the Habib™ VesCoag™ catheter. Angiography and color Doppler ultrasound were used to assess vessel patency immediately following the procedure and six weeks later. One rabbit was sacrificed following the procedure for histopathologic analysis of the vessel wall. Two rabbits died of aortic and carotid rupture, respectively, immediately after the procedure. The remaining seven rabbits were sacrificed after six-week follow-up for histopathological analysis. Optimal RF generator settings to induce significant arterial stenosis (>50%) without complications were standardized at 24-26 watts (W) for 1.5 min for the aorta and 6 W for 1 min for the common carotid artery. The six-week follow-up showed permanent results in all surviving rabbits. Histopathology revealed intima and medial smooth muscle layer necrosis. We have developed a novel rabbit model of arterial stenosis using endovascular RF energy. Our model is fast, safe, inexpensive, and reproducible. It would be useful for experimental investigations and new therapeutic devices.
To investigate the use of a new endovascular radiofrequency (RF) device, the Habib™ VesCoag™ Cath... more To investigate the use of a new endovascular radiofrequency (RF) device, the Habib™ VesCoag™ Catheter, to induce vascular remodeling and dilatation of arterial stenosis in a rabbit model. RF was used to induce arterial stenosis in 10 rabbits and this was confirmed by angiography and color Doppler ultrasound. Two groups of five animals were then subjected to (1) balloon dilatation of the stenosis (intervention group), (2) no intervention (control group). Two rabbits from each group were sacrificed following the procedures to investigate vessel histopathology. At six weeks, the remaining six rabbits underwent follow-up angiogram and color Doppler ultrasound to assess vessel patency. They were then sacrificed and the vessels prepared for histopathological analysis. Three-dimensional images with confocal microscopy of the arterial lumen were also acquired. In the intervention group, stenosis was reversed and patency confirmed by angiography and color Doppler ultrasound six weeks later in all surviving rabbits. Histopathology revealed degenerative changes of elastic fibers, focal losses of elastica lamella, disorganization of myocytes and extensive hyalinization of the tunica adventitia. Focal elastin changes of the arterial elastic lamella were also shown by three-dimensional confocal microscopy images. We have developed a novel endovascular RF catheter that can be safely and effectively used to induce vascular remodeling and dilatation of arterial stenosis in an experimental rabbit model.
We validated the association of simple renal cysts with abdominal aortic aneurysm and other cardi... more We validated the association of simple renal cysts with abdominal aortic aneurysm and other cardiovascular factors and assessed simple renal cysts' impact on renal function before and after endovascular abdominal aortic aneurysm repair. A retrospective analysis of prospectively collected data was conducted. Computed tomography angiograms of 100 consecutive male patients with abdominal aortic aneurysm who underwent endovascular abdominal aortic aneurysm repair (Group 1) were reviewed and compared with 100 computed tomography angiogram of aged-matched male patients without abdominal aortic aneurysm (Group 2). Patients' demographic data, risk factors, abdominal aortic aneurysm diameter, the presence of simple renal cyst and laboratory tests were recorded. No difference was observed between the two groups in respect to other cardiovascular risk factors except hyperlipidemia with higher prevalence in Group 1 (p < 0.05). Presence of simple renal cysts was independently associated with age (p < 0.05) and abdominal aortic aneurysm (p = 0.0157). There was no correlation between simple renal cysts and abdominal aortic aneurysm size or pre-operative creatinine and urea levels. No difference was observed in post-operative creatinine and urea levels either immediately after endovascular abdominal aortic aneurysm repair or in 12-month follow-up. In male patients, the presence of simple renal cysts is associated with abdominal aortic aneurysm and is increasing with age. However, their presence is neither associated with impaired renal function pre-endovascular abdominal aortic aneurysm repair and post-endovascular abdominal aortic aneurysm repair nor after 12-month follow-up.
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