Accuracy of Computed Tomography in the Assessment of Milan Criteria in Liver Transplantation for Hepatocellular Carcinoma.

BACKGROUND: Despite worldwide debate on optimal selection of patients with hepatocellular carcinoma (HCC) for liver transplantation, the Milan criteria remain the benchmark for comparisons. Moreover, morphologic tumor features are universally considered important in pretransplant patient evaluation. The aim of this study was to establish the diagnostic accuracy of multiphasic computed tomography (CT) in assessing HCC burden before liver transplantation with special reference to Milan criteria fulfillment. METHODS: This retrospective study was based on a data from 27 HCC patients after liver transplantation with available CT performed within 30 days pretransplant. CT results were compared with explant pathology with respect to Milan criteria fulfillment, tumor number, and diameter of the largest tumor. RESULTS: Out of 19 patients within the Milan criteria on CT, 3 fell beyond the criteria on explant pathology with a gross underestimation rate of 15.8%. Out of 8 patients beyond the Milan criteria on CT, 3 were within the criteria on explant pathology with a gross overestimation rate of 37.5%. Regarding tumor number, CT was accurate only in 14 patients (51.9%), while overestimation and underestimation occurred in 5 (18.5%) and 8 (29.6%) patients, respectively. Overestimation and underestimation of largest tumor size by at least 1 cm occurred in 4 (14.8%) and 7 (25.9%) patients, respectively. DISCUSSION: Multiphasic CT is associated with a remarkable risk of both under- and overestimation of HCC burden before transplantation. Transplant eligibility should not be solely based on CT results.

Uncommon branching pattern of the hepatic arteries in a living donor: a case report and brief literature review.

Numerous variations of the hepatic arteries are common in surgical patients. We present a 35-year-old woman who was admitted to our department in order to assess possibility of becoming living donor. Preoperative computed tomography scan revealed anomalous branching pattern of the hepatic arteries. In this case right posterior sectoral artery has been given off by the greater pancreatic artery, left hepatic artery has been replaced by the artery arising from the left gastric artery and double segment 4 branches have been observed. To the best of our knowledge, this pattern has not been described in the literature, yet.

Outcomes following liver transplantation for metastatic neuroendocrine tumors.

INTRODUCTION: Metastatic disease is generally considered as an absolute contraindication for liver transplantation. However, due to relatively low aggressiveness and slow progression rates, liver metastases from neuroendocrine tumors (NETs) form an exception to this rule. Given the scarcity of available data, the purpose of this study was to evaluate long-term outcomes following liver transplantation for NET metastases. MATERIAL AND METHODS: There were 12 primary liver transplantations in patients with NET metastases out of 1334 liver transplantations performed in the Department of General, Transplant and Liver Surgery (Medical University of Warsaw) in the period between December 1989 and October 2013. Overall survival (OS) and disease-free survival (DFS) were set as primary and secondary outcome measures, respectively. RESULTS: Median follow-up was 7.9 years. For all patients, OS rate was 78.6% at 10 years and DFS rate was 15.5% at 9 years. Intraoperative transfusions of packed red blood cells (P = .021), Ki-67 proliferative index more than 2% (P = .048), and grade 2 tumors (P = .037) were identified as factors significantly associated with worse DFS. Notably, loss of E-cadherin expression (P = .444), mitotic rate (P = .771), extent of liver involvement (P = .548), primary tumor site (P = .983), and recipient age (P = .425) were not significantly associated with DFS. CONCLUSIONS: Excellent long-term OS rates support liver transplantation for unresectable NET metastases despite almost universal post-transplantation tumor recurrence. Selection of patients with G1 tumors with Ki-67 index not exceeding 2% and reducing the requirement for intraoperative blood transfusions might improve DFS rates.

Role of 16-multidetector computerized tomography in evaluation of graft failure risk in patients with pancreatic graft thrombosis after simultaneous pancreas and kidney transplantation.

BACKGROUND: Thrombosis of the pancreatic graft vessels is a common complication in patients after pancreas transplantation. The aim of this study was to evaluate the usefulness of 16-multidetector computerized tomography (16-MDCT) with volume rendering (VR) and maximum intensity projection (MIP) reconstruction as a predicting method of pancreatic graft loss after simultaneous pancreas and kidney transplantation. METHODS: Within 6-8 days after combined kidney-pancreas transplantation, MDCT was performed in 60 patients. Secondary reconstructions were obtained with the application of VR and MIP algorithms. Vessel anastomosis, extra- and intrapancreatic arteries, venous morphology, and enhancement of graft's parenchyma were evaluated. The stenosis grade of pancreatic graft vessels and the areas of graft parenchyma malperfusion were evaluated. RESULTS: Thrombosis of pancreatic graft vessels was recognized in 26 patients (43%), however only one-half of them required graftectomy. There were 17 cases of large vessel thrombosis and 9 cases of small intragraft vessel thrombosis. In 13 (86.6%) out of 15 recipients parenchymal malperfusion resulted in graft lost. It appeared that vessel narrowing >40% was a threshold for pancreatic graft loss with sensitivity and false positive values of 100% and 9%, respectively. For parenchyma nonenhancement >60% the sensitivity and false positive values of 100% and 0% were significantly associated with pancreatic graft loss (P < .0001). CONCLUSIONS: Vascular occlusion of >40% and necrosis >60% of parenchymal volume correspond with pancreatic graft loss.

Liver regeneration in 120 consecutive living-related liver donors.

BACKGROUND: Living-related liver transplantation for pediatric patients has become an acceptable, low-risk treatment option. The aim of this study was to assess the extent of donor liver regeneration. MATERIALS AND METHODS: Between October 1999 and January 2008, 120 living-related donors provided 109 grafts consisting of segments II and III and 11 grafts consisting of segments II, III, and IV. Volumetric assessment of the donor liver and selected segments was performed using computed tomography. After procurement every graft was weighed. At 7 and 30 days, as well as 12 months after the operation the donor liver remnant was evaluated for differences in volume. RESULTS: A significant correlation was observed between the liver graft mass and its volume as assessed by computed tomography (r = 0.781; P < .05). Twelve months after procurement, the average regeneration index was significantly higher among donors of segments II, III, and IV (144 +/- 23%) versus donors of segments II and III (114 +/- 15%; P < .05). CONCLUSION: Liver regeneration after procurement of selected liver segments from living donors is a consistent finding. Computed tomography is an accurate imaging modality to track changes in liver volume. This study showed a positive correlation between the size of the liver graft and the regeneration of the liver remnant in the donor.

Usefulness of 16-row multidetector computed tomography with volume rendering and maximum intensity projection reconstruction as a monitor pancreatic graft vessel patency during the early postoperative period.

Thrombosis of the pancreatic graft vessels is the most common complication after transplantation. It leads to loss of 5% to 8% of grafts during the early postoperative period. The aims of this study were to evaluate the usefulness of 16-row multidetector computed tomography (16-MDCT) with volume rendering (VR) and maximum intensity projection (MIP) reconstruction to monitor pancreatic graft vessel patency during the early postoperative period and the efficacy of a heparin infusion as a treatment for graft thrombosis. Among 40 consecutive simultaneous pancreas-kidney transplant recipients, 16-MDCT was performed at 6 to 8 days after the operation. Secondary reconstructions were obtained with VR and MIP algorithms to evaluate the morphology and patency of the extra- and intrapancreatic arteries and veins. In cases of thrombosis, every patient was treated with an infusion of unfractionated heparin. In 15 recipients, thrombosis of the large vessels was detected by 16-MDCT. Heparin infusions saved five pancreatic grafts (5/15; 33.3%), but the other 10 pancreatic grafts were removed. In another four recipients (4/40; 10%) the thrombi were localized only in small intrapancreatic vessels. Treatment with heparin infusion was successful in 3/4 (75%) cases with patent vessels upon control computed tomography examination. We compared the efficacy of heparin treatment depending on the diameter of the thrombosed vessel, observing a significant difference (5/15 vs 3/4; P < .01; chi-square). 16-MDCT with secondary reconstruction by application of VR and MIP algorithms was an efficient method to visualize not only large pancreatic graft arteries and veins but also intrapancreatic parenchymal vessels. In cases of thrombosis of small intrapancreatic vessels, unfractionated heparin infusion significantly decreased graft loss.

Evaluation of donor's liver regeneration after left lobe harvesting for living-related liver transplantation.

BACKGROUND: Computerized tomography-assisted volumetry permits one to estimate the volume of the liver graft as well as to monitor the regeneration in the donor for living- related liver transplantation (LRLT). METHODS: The size of the whole liver and of the segments II, III, and IV was assessed in 64 living-related liver donors by preoperative computerized tomography (CT) volumetry. Segments II and III were harvested in 56 cases; segments II, III, and IV in 8 cases. The remnant liver was assessed by CT volumetry on postoperative days 7 and 30. RESULTS: There was a linear correlation between the calculated volume of the graft and its weight (R = 0.61, P < .04). Postoperative CT volumetry of the liver from a living-related donor showed a different pattern of volume restoration (regeneration index) both at 7 and 30 days among donors who sacrificed segments II and III versus segments II, III, and IV. The mean regeneration indices were significantly higher among donors of segments II, III, and IV compared with donors of segments II and III after 7 and 30 days (P < .05). DISCUSSION: It is possible that the donor liver displays a different pattern of growth due to the alteration in the blood supply to segment IV.

Imaging of pancreatic transplant vessels and anastomoses with 16-row multidetector computed tomography.

The aim of this study was to evaluate the usefulness of 16-row multidetector computed tomography (16-MDCT) in the assessment of the potency of arterial and venous vessels in combined kidney-pancreas transplant and detection of transplant-related complications. Fifteen patients underwent a combined kidney-pancreatic transplantation. On the seventh day after the operation, we performed 16-MDCT in arterial and portal venous phase to evaluate vessels, anastomotic sites, and pancreatic parenchymal vascularization as well as peripancreatic fluid collections. We visualized the pancreatic vessels and anastomosis sites in all cases. In 12 recipients, there were no abnormal findings as regards the patency of the arterial and venous vessels and the vascularization of the pancreatic parenchyma. In two patients, complete arterial thrombosis of the body and tail pancreatic graft vessels was recognized at 2 weeks after transplantation, resulting in graft removal. Thrombi were localized in the distal part of anastomoses. None of the patients had venous thrombosis. One recipient had stenosis of the venous anastomosis. Peripancreatic fluid collections were observed in seven patients. In conclusion, 16-MDCT is an efficient method to estimate pancreatic transplant vessels, localize thrombi, and detect other transplant-related complications.

Immune response to and tissue localization of the Wolbachia surface protein (WSP) in dogs with natural heartworm (Dirofilaria immitis) infection.

Human and animal parasitic filarial nematodes, including the agent of canine and feline heartworm disease Dirofilaria immitis, harbour intracellular bacteria of the genus Wolbachia (Rickettsiaies). It is thought that these bacteria play an important role in the pathogenesis and immune response to filarial infection. Immunoglobulin G (total IgG, IgG1, IgG2) production against and immunohistochemical staining of tissues for the Wolbachia surface protein (WSP) from dogs with natural heartworm infection were evaluated. All infected dogs had significant total anti-WSP IgG levels compared to healthy controls. Interestingly, WSP was recognized by the IgG2 subclass in both microfilariemic dogs and in dogs with no circulating microfilariae (occult infection). However, microfilariemic dogs also produced gG1 antibodies. Positive staining for WSP was observed in lungs, liver and kidneys, in particular in glomerular capillaries of naturally infected dogs who had died from heartworm disease. Our results show for the first time that Wolbachia is recognized specifically by D. immitis--infected dogs and that the bacteria is released into host tissue. Furthermore, microfilariemic status appears to effect immune responses to this endosymbiont.

Simultaneous endovascular exclusion of thoracic aortic aneurysm with open abdominal aortic aneurysm repair.

BACKGROUND: The treatment of aneurysms at multiple sites within the aorta is problematic. METHODS: Between March 2002 and June 2003 in the Department of General, Vascular and Transplant Surgery, Medical University of Warsaw six patients with coexisting abdominal and descending thoracic aortic aneurysms underwent simultaneous open abdominal aortic aneurysm (AAA) repair and endoluminal thoracic aortic aneurysm (TAA) repair. The indication for a combined procedure was a diagnosed descending TAA and AAA with no significant risk factors for open aortic surgery or technical contraindications for endovascular treatment of TAA. RESULTS: One patient died in the peri-operative period while the other five patients all recovered well after surgery and were discharged with both aneurysms excluded. CONCLUSION: Endovascular treatment of TAA combined with a simultaneous open AAA repair is an efficient and relatively safe treatment modality in patients with TAA and AAA disqualified from endovascular repair. The fact that thoracotomy is not a necessity significantly lowers the complication rate in these patients.

Anatomical alteration of the vascular tree observed during living related liver transplantation.

INTRODUCTION: The number of available cadaveric donor organs has reached a plateau. One current solution has been to increase number of living related liver transplantations. MATERIAL AND METHODS: Since October 1999 in the Department of General, Transplant and Liver Surgery, Medical University of Warsaw, 40 living related liver transplantation have been carried out. RESULTS: In 31 (77.5%) cases, a normal arterial supply was observed: the common hepatic artery arose from a celiac trunk. In two cases (5.0%), there was a partial arterial blood supply by the right accessory hepatic artery originating from the superior mesenteric artery. In two cases (5.0%), a right hepatic artery arose completely from the superior mesenteric artery (replaced artery). In one case (2.5%), a common hepatic artery originated from the superior mesenteric artery. In two cases (5.0%), an accessory left segmental artery originated from the left gastric artery. In two cases (5.0%), the function of an absent left hepatic artery was assumed by a replaced left hepatic artery originating from the left gastric artery. In two (5.0%) cases, there were two separate ducts draining the right hemiliver. There were two (5.0%) cases of an accessory duct draining segment IV, originating within the confluence of the right and left hepatic ducts. In one (2.5%) case, the common hepatic duct showed a trifurcation. CONCLUSION: During harvesting from a living donor knowledge of anatomical variants must be used to optomize the liver graft.

Harvesting liver fragments from living-related donors: a single-center experience.

The aim of the study was to estimate the risk of harvesting a liver fragment from a living-related adult donor. Liver fragments were harvested from 44 donors. Liver segments II and III were harvested from 36 donors. Liver segments II, III, IV were harvested from 6 donors, 2 donors gave segments V, VI, VII, and VIII. After preliminary donor selection volumetric assessment of liver segments by computed tomography and arteriography was performed to visualize the cenac trunk and superior mesenteric artery. None of the donors died. No complications were observed during the operation. Only one case, a bile collection, was observed after surgery. We treated this patient with a satisfactory result by sonography-guided drainage. We observed temporary elevation of bilirubin and transaminase levels and a decrease in prothrombin index value. Blood transfusion was not necessary during any of the procedures. Mean hospitalization time after the surgery was 9.4 days. Mean graft weight/recipient weight ratio was 2.54%. The risk of the harvesting liver fragment from a living-related adult donor seems to be minimal.

The impact of experience of a transplantation center on the outcomes of orthotopic liver transplantation.

The so-called learning factor has been disregarded for many years in analyzing the causes of surgical complications and post-operative mortality; it is also the case for OLT. In our center until April 2003, 209 OLT were performed in 196 patients. We evaluated the impact of experience of the transplantation team on the outcomes of liver transplantation. Thirty-four patients died (mortality rate, 16%) and 1-year survival rate, 64%. Mortality rates varied during different periods of observation due to increasing experience of the transplantation team. The causes of mortality were assessed for a series of 34 patients: it was 75% at the beginning of transplantation procedures while recent deaths have not recently exceeded 10% of cases.

Vascular complications after liver transplantation.

Vascular complications following liver transplantation is reviewed based upon literature data and our own results. Our study conclusions are mostly based on literature data, because our center does not have the liver transplantation experience of other centers worldwide. Thus, we may conclude, that the number and character of complications does not differ from those reported by other centers. The enbloc technique used in liver harvesting minimizes the risk of arterial damage in case of vascular anomalies. Recipient retransplantation is the most effective treatment method in cases of hepatic arterial occlusion. Doppler ultrasound examinations are effective to monitor vascular blood flow in the transplanted liver.

Liver regeneration in living-related donors after harvesting of liver segments II and III or II, III and IV.

BACKGROUND: CT-assisted volumetry permits an estimation of the volume of the graft in liver transplantation, as well as monitoring the donor's liver regeneration. The aim of the study was to observe the restitution of liver tissue in donors after harvesting of the liver fragment for living-related liver transplantation (LRLT). METHODS: The size of the whole liver and of segments II, III and IV was assessed by preoperative CT volumetry in 29 living-related liver donors. Segments II and III were harvested in 22 patients, segments II, III and IV in 6 patients. The remnant liver was assessed by CT volumetry on the 7th and 30th postoperative days. RESULTS: The correlation between the calculated volume of the graft and its weight was linear (r=0.56, p<0.04). Postoperative CT volumetry of the liver of living-related donors showed a different pattern of volume restoration (regeneration index) at both 7 and 30 days between donors who sacrificed segments II and III and those who sacrificed segments II, III and IV. The mean regeneration indexes were significantly higher in donors of segments II, III and IV as compared with donors of segments II and III (7 days, p<0.02; 30 days, p<0.05). DISCUSSION: It is possible that the donor's liver displays a different pattern of growth due to the alteration in blood supply to segment IV.

Diagnostic value of transoesophageal echocardiography in suspected haemodynamically significant pulmonary embolism.

OBJECTIVE: To assess the value of transoesophageal echocardiography (TOE) for diagnosing suspected haemodynamically significant pulmonary embolism and signs of right ventricular overload at standard echocardiography. METHODS: 113 consecutive patients (58 male; 55 female), mean (SD) age 53.6 (13.3) years, in whom there was clinical suspicion of pulmonary embolism and right ventricular overload on transthoracic echocardiography, underwent TOE in addition to routine diagnostic procedures to identify pulmonary artery thrombi. RESULTS: TOE revealed thrombi in 32 of 51 patients who had suspected acute pulmonary embolism and in 31 of 62 with suspected chronic pulmonary embolism. In one patient a pulmonary angiosarcoma rather than chronic pulmonary embolism was found at surgery. The diagnosis of pulmonary embolism was confirmed in 77 patients by scintigraphy, spiral computed tomography, angiography, or necropsy (reference methods). While TOE failed to provide a diagnosis of pulmonary embolism in 15 of these 77 patients, no false positive findings were reported (sensitivity 80.5%, specificity 97.2%). In 11 and 26 cases, respectively, the thrombi were confined to the left or right pulmonary artery. Bilateral thrombi were found in 25 patients. Mobile thrombi were observed only in acute pulmonary embolism (in 19 of 32 patients). No complications of TOE were noted. CONCLUSIONS: TOE permits visualisation of pulmonary arterial thrombi, confirming the diagnosis in the majority of patients with pulmonary embolism and right ventricular overload. This may be useful for prompt decision making in patients with haemodynamic compromise considered for thrombolysis or embolectomy.