Thrombosis of mechanical cardiac valves: a qualitative comparison of the silastic ball valve and the tilting disc valve.

A review of 817 mitral and aortic Silastic ball valve implantations with a follow-up of 3,554 total patient-years yielded only seven cases of valve thrombosis. Time-related risk was 0.4% per patient-year in the mitral position and 0.1% per patient-year in the aortic position. Four of five mitral and one of two aortic ball valve thromboses were successfully managed by valve rereplacement . At least five of the seven patients presented with a prodrome (lasting at least 3 months) of symptoms of progressive heart failure and, occasionally, embolic episodes due to gradually increasing prosthetic stenosis by thrombus. This lengthy time course is in contrast to the more frequent rapid catastrophic thrombosis that occurs with the Björk-Shiley tilting disc valve. Recognition of the prodrome of Silastic ball valve thrombosis provides an opportunity for life-saving surgical intervention.

Late results of combined mitral valve replacement and coronary bypass surgery.

The incremental risk of coronary bypass surgery was analyzed in 718 patients undergoing mitral valve replacement between 1971 and 1983. Ninety-eight patients (14%) had significant coronary artery disease requiring coronary bypass surgery. In 70 of these patients, the origin of the mitral valve disease was nonischemic, whereas 28 patients had ischemic mitral regurgitation unsuitable for conservative valve surgery. There were six operative deaths (9%) and four perioperative myocardial infarctions (6%) after mitral valve replacement and coronary bypass surgery for nonischemic mitral valve disease. Operative mortality was related to low output cardiac failure before operation or perioperative myocardial infarction. Actuarial curves predict survival (+/- standard error) of 55 +/- 7% at 5 years and 43 +/- 8% at 10 years. Preoperative functional class was the only significant predictor of long-term survival in this group (p less than 0.05). The actuarial survival of the 620 patients without coronary artery disease who underwent mitral valve replacement alone was 63 +/- 3% at 10 years. This was significantly better than that of the 70 patients who underwent mitral valve replacement and coronary bypass surgery for nonischemic mitral valve disease (p less than 0.001). Conversely, 5 year survival of the 28 patients with ischemic mitral regurgitation was 43 +/- 10%. This confirms the negative detrimental effect of an ischemic origin of mitral valve disease on survival after mitral valve replacement and coronary bypass surgery (p less than 0.0001).

The impact of a laparoscopic colorectal surgeon on the laparoscopic colectomy experience of a single academic center.

BACKGROUND: The objective of this study was to evaluate the impact of a laparoscopic colorectal surgeon (LCRS) on the laparoscopic colectomy experience of a single academic center. METHODS: We performed a retrospective review of case complexity, patient characteristics, operative and preparation time, and trends over time for the LCRS compared to two veteran laparoscopic surgeons (VLS). RESULTS: The LCRS performed 48 of the procedures (83%) and the VLS 10 (17%) for a total of 58 laparoscopic colon cases. The LCRS handled a greater number of complex cases (p = 0.07). For less complex cases, overall operative time differed for the two groups (LCRS = 220 +/- 11 vs VLS = 152 +/- 15 min, p = 0.004). Overall hospital stay was 4.8 +/- 0.6 days (range, 2-33). Minor complications occurred in 12 cases (21%); major complications in occurred in seven cases (12%). Among procedures performed by the LCRS, comparison of the first 24 cases to the second 24 demonstrated that operative and preparation time decreased in the second cohort (all p < 0.05). CONCLUSION: The addition of an LCRS had a significant impact on this center's experience with laparoscopic colectomies in terms of both volume and case complexity.

Decreased patient analgesic requirements after liver transplantation and associated neuropeptide levels.

BACKGROUND: Decreased morphine requirements have been reported after liver transplantation when compared with other types of major abdominal surgery. The aim of this study was to examine plasma concentrations of three neuropeptides involved in pain modulation-metenkephalin (ME), beta-endorphin (BE), and substance P (SP)-in patients undergoing orthotopic liver transplantation (OLT) and in control patients undergoing other liver operations. We then compared the postoperative analgesic requirements in these two groups of patients. METHODS: Plasma levels of ME, BE, and SP were measured by radioimmunoassay at preincision, preemergence, and for 3 days after operation in 13 patients undergoing OLT and in 10 control patients. Patient-controlled analgesia morphine delivery was recorded for all patients postoperatively, and plasma morphine, its metabolites, and patient pain and sedation scores were also measured. RESULTS: ME levels were elevated in all OLT patient samples when compared with control patient samples. BE levels were not significantly different at any time. SP levels were significantly decreased only in preincision and preemergence OLT patient samples. Total patient-controlled analgesia morphine delivered during the first 3 postoperative days was significantly less in OLT patients (70+/-8 mg) than in control patients (101+/-12 mg). Plasma morphine, morphine-3-glucuronide, and morphine-6-glucuronide levels were decreased in OLT patients, however, statistical significance was seen only in the morphine-6-glucuronide results. CONCLUSIONS: We have shown that postoperative analgesic requirements are decreased in OLT patients, and we suggest that associated increased peripheral ME levels may be contributing to this decreased requirement. Based on our results, circulating BE and SP are less significant factors affecting postoperative analgesic requirements.

Plasma prostaglandin E1 concentrations and hemodynamics during intravenous infusions of prostaglandin E1 in humans and swine.

Prostaglandin (PG) E1 administered intravenously has been used for the treatment of primary nonfunction of hepatic allografts and fulminant hepatic failure. It has been proposed that this therapy may improve hepatic blood flow via the vasodilating properties of PGE1. However, PGE1 undergoes extensive metabolic inactivation by the lung and the concentration of PGE1 reaching the liver during intravenous administration has not been determined. Thus, we measured plasma PGE1 concentrations in patients with hepatic dysfunction being treated with PGE1 and in a swine model of PGE1 infusion. We also determined the hemodynamic effects of PGE1 infusion in swine. Blood was sampled from the pulmonary artery, carotid artery, portal vein, and hepatic vein in swine infused with PGE1 (range, 0.67-4.9 microg/kg/hr) demonstrating: (1) a pulmonary extraction ratio of PGE1 of 0.78 +/- 0.12, (2) a splanchnic extraction ratio of PGE1 of 0.54 +/- 0.23, and (3) levels of PGE1 in the systemic circulation of

Staging recurrent metastatic colorectal carcinoma with PET.

UNLABELLED: Accurate detection of recurrent colorectal carcinoma remains a diagnostic challenge. The purposes of this study were to assess the accuracy of 18FDG-PET in patients with recurrent colorectal carcinoma in detecting liver metastases compared with computed tomography (CT) and CT portography, detecting extrahepatic metastases compared with CT and evaluating the impact on patient management. METHODS: Fifty-two patients previously treated for colorectal carcinoma presented on 61 occasions with suspected recurrence and underwent 18FDG-PET of the entire body. PET, CT and CT portography images were analyzed visually. The final diagnosis was obtained by pathology (n = 44) or clinical and radiological follow-up (n = 17). The impact on management was reviewed retrospectively. RESULTS: A total of 166 suspicious lesions were identified. Of the 127 intrahepatic lesions, 104 were malignant, and of the 39 extrahepatic lesions, 34 were malignant. Fluorine-18-fluorodeoxyglucose imaging was more accurate (92%) than CT and CT portography (78% and 80%, respectively) in detecting liver metastases and more accurate than CT for extrahepatic metastases (92% and 71%, respectively). Fluorine-18-fluorodeoxyglucose detected unsuspected metastases in 17 patients and altered surgical management in 28% of patients. CONCLUSION: These data identify that 18FDG-PET is the most accurate noninvasive method for staging patients with recurrent metastatic colorectal carcinoma and plays an important role in management decisions in this setting.

Optimal interpretation of FDG PET in the diagnosis, staging and management of pancreatic carcinoma.

UNLABELLED: This study had two purposes: to optimize the semiquantitative interpretation of 18F-fluorodeoxyglucose (FDG) PET scans in the diagnosis of pancreatic carcinoma by analyzing different cutoff levels for the standardized uptake value (SUV), with and without correction for serum glucose level (SUV(gluc)); and to evaluate the usefulness of FDG PET when used in addition to CT for the staging and management of patients with pancreatic cancer. METHODS: Sixty-five patients who presented with suspected pancreatic carcinoma underwent whole-body FDG PET in addition to CT imaging. The PET images were analyzed visually and semiquantitatively using the SUV and SUV(gluc). The final diagnosis was obtained by pathologic (n = 56) or clinical and radiologic follow-up (n = 9). The performance of CT and PET at different cutoff levels of SUV was determined, and the impact of FDG PET in addition to CT on patient management was reviewed retrospectively. RESULTS: Fifty-two patients had proven pancreatic carcinoma, whereas 13 had benign lesions, including chronic pancreatitis (n = 10), benign biliary stricture (n = 1), pancreatic complex cyst (n = 1) and no pancreatic pathology (n = 1). Areas under receiver operating characteristic curves were not significantly different for SUV and SUV(gluc). Using a cutoff level of 3.0 for the SUV, FDG PET had higher sensitivity and specificity than CT in correctly diagnosing pancreatic carcinoma (92% and 85% versus 65% and 61%). There were 2 false-positive PET (chronic pancreatitis, also false-positive with CT) and 4 false-negative PET (all with true-positive CT, abnormal but nondiagnostic) examinations. There were 5 false-positive CT (4 chronic pancreatitis and 1 pancreatic cyst) and 18 false-negative CT (all with true-positive FDG PET scans) examinations. FDG PET clarified indeterminate hepatic lesions or identified additional distant metastases (or both) in 7 patients compared with CT. Overall, FDG PET altered the management of 28 of 65 patients (43%). CONCLUSION: FDG PET is more accurate than CT in the detection of primary tumors and in the clarification and identification of hepatic and distant metastases. The optimal cutoff value of FDG uptake to differentiate benign from malignant pancreatic lesions was 2.0. Correction for serum glucose did not significantly improve the accuracy of FDG PET. Although FDG PET cannot replace CT in defining local tumor extension, the application of FDG PET in addition to CT alters the management in up to 43% of patients with suspected pancreatic cancer.

Histopathology of the donor gallbladder removed at orthotopic liver transplantation: correlation with graft function.

The histopathology of 50 consecutive donor gallbladders removed during orthotopic liver transplantation was reviewed and correlated with graft function. Multiple sections of the gallbladders were examined for the presence of mucosal congestion, hemorrhage, and necrosis, without prior knowledge of the clinical outcome. Each pathologic feature was graded as absent (0), involving less than 10% (1+), 10% to 50% (2+), or more than 50% (3+) of the histologically examined mucosa. Graft function was determined by two transplant surgeons, a poor diagnosis being worsening of liver function tests associated with declining mental status and resulting in immediate retransplantation or early postoperative death; all others were categorized as good. Of 39 patients with good graft function, 18 had normal donor gallbladders, 11 had congestion only, and 10 had hemorrhage and/or necrosis. Of 11 patients with poor graft function, eight had hemorrhage and/or necrosis (2+ in seven), three had congestion only, and none had a normal gallbladder mucosa. Congestion alone was found to be a poor predictor of graft damage. Presence of any grade of hemorrhage and/or necrosis in donor gallbladders as related to poor liver graft function had a sensitivity of 73%, a specificity of 74%, a positive predictive value of 44%, and a negative predictive value of 91%. When hemorrhage and/or necrosis of 2+ severity was separately grouped and correlated with poor graft function, the specificity rose to 97% and the positive predictive value to 88%, and the negative predictive value was similar at 90%. We conclude that donor gallbladders often show mucosal abnormalities consisting of varying degrees of congestion, hemorrhage, and necrosis. The finding of hemorrhage and/or necrosis affecting more than 10% of the mucosa appears to be a specific lesion of ischemic damage that correlates highly with poor liver graft function.

Valvotomy for pulmonary atresia with intact ventricular septum. A disciplined approach to achieve a functioning right ventricle.

During the past 20 years, a consistent policy in applying early valvotomy has resulted in a unique opportunity to appraise the long-term results of this approach in pulmonary atresia with intact ventricular septum. Since 1964, 27 of 35 patients with pulmonary atresia with intact ventricular septum had type 1 or 2 right ventricle, 25 of these had early valvotomy, seven with and 18 without concomitant shunt. The remaining two patients with type 2 right ventricle and the eight patients with type 3 right ventricle received a shunt alone. Overall operative mortality was 34%; for those patients weighing more than 3 kg and those operated upon since 1977, it was 18% and 16%, respectively. There were 17 survivors of early valvotomy: 11 had valvotomy alone and six had valvotomy with shunt; 12 had type 1 right ventricle and five had type 2 right ventricle. Survival rates (+/- standard error) for these 17 patients were 85% +/- 10% and 68% +/- 17% at 5 and 10 years, respectively. The probability of reoperation was 100% by 6 years of age; outflow patch reconstruction was employed in all patients in whom reoperation has been performed. Aggressive follow-up and early recatheterization were essential features of management. Delayed reconstruction after shunt alone was unsuccessful in three patients. Primary valvotomy without shunt is the operation of choice for patients with pulmonary atresia with intact ventricular septum and type 1 right ventricle. Concomitant shunt may be required for some patients with type 1 and most with type 2 right ventricle, selected preoperatively by angiography or after valvotomy by clinical necessity. Delayed right ventricular reconstruction after shunt alone is not an acceptable approach when an outflow tract is present.

Late surgical results for ischemic mitral regurgitation. Role of wall motion score and severity of regurgitation.

The indication for concomitant valve operations for ischemic mitral regurgitation is examined in 120 consecutive patients with regurgitation who had coronary bypass. Ischemic mitral regurgitation was mild in 56%, moderate in 18%, and severe in 27%. Compared with patients without mitral regurgitation who underwent coronary bypass, significantly more patients with regurgitation had cardiomegaly (31% versus 5%), left heart failure (42% versus 6%), and abnormal wall motion scores (71% versus 42%). Eighty-three patients (69%) with ischemic mitral regurgitation had coronary bypass alone and 37 (31%) also had a valve operation. All patients with mild ischemic mitral regurgitation were treated by coronary bypass alone, as compared to 67% with moderate and 6% with severe regurgitation. Operative mortalities for mild, moderate, and severe ischemic mitral regurgitation were 4%, 10%, and 38%, respectively; 5 year survival rates were 82%, 60%, and 48%, respectively. Other significant determinants of survival were wall motion score, shock, cardiomegaly, left heart failure, and acute and multiple myocardial infarctions. Patients with mild ischemic mitral regurgitation and a low wall motion score (n = 40) had a 5 year survival rate of 94%. For patients with either moderate/severe regurgitation (n = 27) or a high wall motion score (n = 25), but not both, the 5 year survival rate was 70%. In 20 patients with both a high wall motion score and moderate/severe regurgitation, it was 33%. An additive detrimental effect is apparent. The change from mild to moderate/severe ischemic mitral regurgitation was equivalent to an increase of about 8 wall motion score units in terms of effect on survival. Ischemic mitral regurgitation is a powerful additive risk factor to wall motion score in coronary bypass. Mild regurgitation is best managed by coronary bypass alone. If regurgitation is moderate, it may still be possible to avoid a valve operation and have acceptable results. Severe ischemic mitral regurgitation usually necessitates coronary bypass and a mitral valve operation.

Lung allocation in the United States, 1995-1997: an analysis of equity and utility.

BACKGROUND: Waiting time for organ transplantation varies widely between programs of different sizes and by geographic regions. The purpose of this study was to determine if the current lung-allocation policy is equitable for candidates waiting at various-sized centers, and to model how national allocation based solely on waiting time might affect patients and programs. METHODS: UNOS provided data on candidate registrations; transplants and outcomes; waiting times; and deaths while waiting for all U.S. lung-transplant programs during 1995-1997. Transplant centers were categorized based on average yearly volume: small (< or = 10 pounds sterling transplants/year; n = 46), medium (11-30 transplants/year; n = 29), or large (>30 transplants/year; n = 6). This data was used to model national organ allocation based solely on accumulated waiting time for candidates listed at the end of 1997. RESULTS: Median waiting time for patients transplanted was longest at large programs (724-848 days) compared to small and medium centers (371-552 days and 337-553 days, respectively) and increased at programs of all sizes during the study period. Wait-time-adjusted risk of death correlated inversely with program size (365 vs 261 vs 148 deaths per 1,000 patient-years-at-risk at small, medium, and large centers, respectively). Mortality as a percentage of new candidate registrations was similar for all program categories, ranging from 21 to 25%. Survival rates following transplantation were equivalent at medium-sized centers vs large centers (p = 0.50), but statistically lower when small centers were compared to either large- or medium-size centers (p < or = 0.05). Using waiting time as the primary criterion lung allocation would acutely shift 10 to 20% of lung-transplant activity from medium to large programs. CONCLUSIONS: 1) Waiting list mortality rates are not higher at large lung-transplant programs with long average waiting times. 2) A lung-allocation algorithm based primarily on waiting-list seniority would probably disadvantage candidates at medium-size centers without improving overall lung-transplant outcomes. 3) If fairness is measured by equal distribution of opportunity and risk, we conclude that the current allocation system is relatively equitable for patients currently entering the lung-transplant system.

Acute lung injury after hepatic cryoablation: correlation with NF-kappa B activation and cytokine production.

BACKGROUND: Previous clinical reports have documented multisystem organ injury after hepatic cryoablation. We hypothesized that hepatic cryosurgery, but not partial hepatectomy, induces a systemic inflammatory response characterized by distant organ injury and overproduction of nuclear factor kappa B (NF-kappa B)-dependent, proinflammatory cytokines. METHODS: In this study, rats underwent either cryoablation of 35% of liver parenchyma or a similar resection of left hepatic tissue. Serum tumor necrosis factor-alpha and macrophage inflammatory protein-2 levels and NF-kappa B activation were assessed by electrophoretic mobility shift assay at 30 minutes 1, 2, 6, and 24 hours after either procedure. RESULTS: Cryoablation of 35% of liver (n = 22 rats) resulted in lung injury and a 45% mortality rate within 24 hours of surgery, whereas 7% treated with 35% hepatectomy (n = 15 rats) died during the 24 hours after surgery (P < .05, cryoablation vs hepatectomy). Serum tumor necrosis factor-alpha and macrophage inflammatory protein-2 levels were markedly increased in rats (n = 10 rats) 1 hour after hepatic cryoablation compared with rats that underwent partial hepatectomy (P < .005). We evaluated NF-kappa B activation by electrophoretic mobility shift assay in nuclear extracts of liver and lung after cryosurgery and found that NF-kappa B activation was strikingly increased in the liver but not the lung at 30 minutes and in both organs 1 hour after cryosurgery, and returned to baseline in both organs by 2 hours. In rats undergoing 35% hepatectomy, no increase in NF-kappa B activation was detected in nuclear extracts of either liver or lung at any time point. CONCLUSIONS: These data show that hepatic cryosurgery results in systemic inflammation with activation of NF-kappa B and increased production of NF-kappa B-dependent cytokines. Our data suggest that lung injury and death in this animal model is mediated by an exaggerated inflammatory response to cryosurgery.

Effect of donor-disseminated intravascular coagulation in liver transplantation.

It is not known whether disseminated intravascular coagulation, present in a large percentage of organ donors, affects patient outcome after liver transplantation. We reviewed our first 55 liver transplantations and identified 10 donors with disseminated intravascular coagulation. We compared the perioperative courses of the 10 recipients of these transplanted livers with those of 10 matched controls whose donors did not have disseminated intravascular coagulation. Disseminated intravascular coagulation recipients did not require more blood products during or after surgery; their hepatic enzyme levels and prothrombin times after surgery were not statistically significantly higher than those of the controls. There was no difference in hospital stay, number of episodes of rejection, retransplantations, or deaths. The presence of disseminated intravascular coagulation in donors did not adversely affect graft function or patient outcome and should not be a sole criterion for rejecting a liver for transplantation.

Long-term results with primary retroperitoneal tumors.

Primary retroperitoneal tumors represent a variety of lesions, with different treatments and prognoses. Of 182 patients in our study, retroperitoneal tumor was recognized preoperatively in only 39% of them. Sarcomas were most common (43% of patients), followed by lymphomas (23%), benign tumors (11%), undifferentiated malignant tumors (11%), carcinomas (8%), and germ cell tumors (4%). In 81 patients since 1960, the resection rate was 50%. Operative determinants of resectability were pathologic category and grade and extent of tumor. Resection included segments of the gastrointestinal tract (30% of the patients), kidney (25%), and pancreas, bladder, spleen, aorta, and vena cava (for each, 5% or less of the patients). The operative mortality was 6%. Tumor caused late death in 95% of the patients. Pathologic findings were a significant determinant of survival in the 81 patients. For sarcomas, 69% of the patients underwent resection, and the 1- and 5-year actuarial survival rates were 80% and 43%, respectively. Sixty percent of these patients underwent multiple operations. For lymphomas, most patients were treated with radiotherapy and chemotherapy; the 1- and 5-year survival rates were 67% and 35%, respectively. Benign tumors, almost all resected, yielded a 5-year survival rate of 100%. Undifferentiated tumors and carcinomas, most treated with radiotherapy and chemotherapy, had a 1-year survival rate of less than 33%. Other determinants of survival were age, weight loss, grade of tumor, and extent of tumor. Patients who underwent palliative resection had the same survival rate as patients who underwent biopsy alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatic cryoablation-induced acute lung injury: pulmonary hemodynamic and permeability effects in a sheep model.

HYPOTHESIS: Hepatic cryoablation of 30% to 35% or more of liver parenchyma in a sheep model results in eicosanoid and nuclear factor-kappaB (NF-kappaB)-mediated changes in pulmonary hemodynamics and lung permeability. SETTING: Laboratory. INTERVENTIONS: At initial thoracotomy, catheters were placed in the main pulmonary artery, left atrium, right carotid artery, and efferent duct of the caudal mediastinal lymph node for subsequent monitoring in adult sheep. After a 1- to 2-week period of recovery, animals underwent laparotomy and left-lobe cryoablation (approximately 35% by volume) with subsequent awake monitoring and on postoperative days 1 to 3. MAIN OUTCOME MEASURES: Cryoablation-induced lung permeability and hemodynamic changes were compared with baseline values in sheep that underwent instrumentation. Similarly handled sheep underwent resection of a similar volume of hepatic parenchyma or had pulmonary artery pressure increases induced by mechanical left atrial obstruction. Activation of NF-kappaB was assessed with electrophoretic mobility shift assay, and serum thromboxane levels were measured with mass spectroscopy. RESULTS: Cryoablation resulted in acutely increased mean pulmonary (20 to 35 cm water) and systemic pressures, which returned to baseline at 24 hours with no change in cardiac output. Serum thromboxane levels increased 30 minutes after cryoablation (9-fold) and returned to baseline at 24 hours. Activation of NF-kappaB was present in liver and lung tissue by 30 minutes after cryoablation. Lung lymph-plasma protein clearance markedly exceeded the expected increase from pulmonary pressures alone, and increased lymph-plasma protein ratio persisted after pulmonary artery pressures normalized. Similar changes were not associated with 35% hepatic resection. CONCLUSIONS: This study demonstrates that 35% hepatic cryoablation results in an acute but transient increase in pulmonary artery pressure that may be mediated by increased thromboxane levels. Increases in pulmonary capillary permeability are not accounted for by pressure changes alone, and may be a result of NF-kappaB-mediated inflammatory mechanisms. These data show that cryosurgery causes pathophysiological changes similar to those observed with endotoxin and other systemic inflammatory stimuli.

Evaluation of benign vs malignant hepatic lesions with positron emission tomography.

BACKGROUND: In most malignant cells, the relatively low level of glucose-6-phosphatase leads to accumulation and trapping of [18F]fluorodeoxyglucose (FDG) intracellularly, allowing the visualization of increased uptake compared with normal cells. OBJECTIVES: To assess the value of FDG positron emission tomography (PET) to differentiate benign from malignant hepatic lesions and to determine in which types of hepatic tumors PET can help evaluate stage, monitor response to therapy, and detect recurrence. DESIGN: Prospective blinded-comparison clinical cohort study. SETTING: Tertiary care university hospital and clinic. PATIENTS: One hundred ten consecutive referred patients with hepatic lesions 1 cm or larger on screening computed tomographic (CT) images who were seen for evaluation and potential resection underwent PET imaging. There were 60 men and 50 women with a mean (+/-SD) age of 59 +/- 14 years. Follow-up was 100%. INTERVENTIONS: A PET scan using static imaging was performed on all patients. The PET scan imaging and biopsy, surgery, or both were performed, providing pathological samples within 2 months of PET imaging. All PET images were correlated with CT scan to localize the lesion. However, PET investigators were unaware of any previous interpretation of the CT scan. MAIN OUTCOME MEASURES: Visual interpretation, lesion-to-normal liver background (L/B) ratio of radioactivity, and standard uptake value (SUV) were correlated with pathological diagnosis. RESULTS: All (100%) liver metastases from adenocarcinoma and sarcoma primaries in 66 patients and all cholangiocarcinomas in 8 patients had increased uptake values, L/B ratios greater than 2, and an SUV greater than 3.5. Hepatocellular carcinoma had increased FDG uptake in 16 of 23 patients and poor uptake in 7 patients. All benign hepatic lesions (n = 23), including adenoma and fibronodular hyperplasia, had poor uptake, an L/B ratio of less than 2, and an SUV less than 3.5, except for 1 of 3 abscesses that had definite uptake. CONCLUSIONS: The PET technique using FDG static imaging was useful to differentiate malignant from benign lesions in the liver. Limitations include false-positive results in a minority of abscesses and false-negative results in a minority of hepatocellular carcinoma. The PET technique was useful in tumor staging and detection of recurrence, as well as monitoring response to therapy for all adenocarcinomas and sarcomas and most hepatocellular carcinomas. Therefore, pretherapy PET imaging is recommended to help assess new hepatic lesions.

Image-guided surgery: preliminary feasibility studies of frameless stereotactic liver surgery.

BACKGROUND: Liver surgery can be difficult because there are few external landmarks defining hepatic anatomy and because the liver has significant vascularity. Although preoperative tomographic imaging (computed tomography or magnetic resonance imaging) provides essential anatomical information for operative planning, at present it cannot be used actively for precise localization during surgery. Interactive image-guided surgery involves the simultaneous real-time display of intraoperative instrument location on preoperative images (computed or positron-emission tomography or magnetic resonance imaging). Interactive image-guided surgery has been described for tumor localization in the brain (frameless stereotactic surgery) and allows for interactive use of preoperative images during resections or biopsies. HYPOTHESIS: The application of interactive image-guided surgery (IIGS) is feasible for hepatic procedures from a biomedical engineering standpoint. METHODS: We developed an interactive image-guided surgery system for liver surgery and tested a porcine liver model for tracking liver motion during insufflation; liver motion during respiration in open procedures in patients undergoing hepatic resection; and tracking accuracy of general surgical instruments, including a laparoscope and an ultrasound probe. RESULTS: Liver motion due to insufflation can be quantified; average motion was 2.5+/-1.4 mm. Average total liver motion secondary to respiration in patients was 10.8 +/-2.5 mm. Instruments of varying lengths, including a laparoscope, can be tracked to accuracies ranging from 1.4 to 2.1 mm within a 27-m3 (3 X 3 X 3-m) space. CONCLUSION: Interactive image-guided surgery appears to be feasible for open and laparoscopic hepatic procedures and may enhance future operative localization.

Late right ventricular reconstruction following valvotomy in pulmonary atresia with intact ventricular septum.

Experience over two decades in the surgical management of pulmonary atresia with intact ventricular septum demonstrates that eventual right ventricular (RV) reconstruction is possible in the majority of patients surviving valvotomy in infancy. Ten of 17 operative survivors of early valvotomy have eventually received a patch graft to the RV outflow tract, with no reoperative deaths (mean follow-up, 7.4 years). RV systolic pressures, suprasystemic prior to reoperation, are near normal after outflow patch reconstruction. Serial cineangiograms show evidence of RV growth by measurement of tricuspid annulus diameter (TAD), and demonstrate a rate of growth [d(TAD)/d(body length)] greater than a normal rate derived from autopsy data. The mean TAD growth rate is significantly greater than that of patients with less favorable ventricle types treated with a systemic-pulmonary shunt alone. Measurement of TAD is a useful method for following RV growth, and may aid in selecting patients for RV reconstruction.

Experience with transplantation in the treatment of liver cancer.

Thirteen patients with hepatic tumors, from the Boston Center for Liver Transplantation, have been transplanted among a total of 169 recipients. Ten were transplanted primarily for tumor, while three other patients harbored incidental tumors. Two perioperative deaths occurred (15%). Eight patients had hepatocellular carcinoma, one hepatoblastoma and four bile duct (Klatskin) tumors. Two of the bile duct cancers recurred with patient deaths at 9 and 10 months. The remaining nine patients are alive from between 1 month and 36 months postoperatively. A selected review of the literature allowed analysis of follow-up on 185 patients transplanted for tumor. Overall, the proportion of patients transplanted for tumor was 16%. Fifty-two percent of patients had hepatocellular carcinomas (HCC), 24% cholangiocarcinomas, 10% other primary liver tumors, and 14% metastatic hepatic tumors. Median survival for HCC was 1 year; 90-day mortality was 30%. Actuarial survival for 1, 2 and 3 years was 49%, 37% and 30% respectively. Fibrolamellar HCC and incidental HCC had significantly better results than other HCC. Tumor recurrence was present in 72% of autopsies after 90 days. Transplantation for HCC has satisfactory results in selected patients and may be improved by adjuvant chemotherapy. The median survival with cholangiocarcinomas was 8 months; 90-day mortality was 40%. Actuarial survival for 1 year was 36%. Recurrence was present in 100% of autopsies after 90 days. Survival after transplantation for this tumor was similar to that observed in patients not undergoing surgical treatment. Median survival for 18 other primary hepatic tumors was 16 months. Transplantation in carefully selected patients with these other primary tumors appears warranted. Although experience overall with transplantation for metastatic disease has been relatively unfavorable, each histological type must be considered independently.

General surgical complications after cardiopulmonary bypass surgery.

In a single institution, 142 general surgical complications were found in a total of 82 patients after 5,682 cardiac procedures. There were 54 complications in 40 patients within 6 weeks of surgery and 88 complications more than 6 weeks after surgery. There were 12 deaths in the early group and one death in the late group. The incidence of these general surgical complications was low in both the early and late groups (0.9 percent and 1.6 percent, respectively). The mortality rate of general surgical complication within the early group was 23 percent. After 6 weeks the mortality rate was less than 2 percent. Mortality was higher following valve procedures than following coronary artery bypass operations in the early period. Anticoagulation and arrhythmias were both minimal management problems after general surgical operations. The anatomic area most frequently involved was the biliary tract. Documented low cardiac output preceded many of these complications in the early group.