Single imaging modality evaluation of living donors in liver transplantation: magnetic resonance imaging

BACKGROUND

Liver graft size, anatomy of the bile duct and the vascular inflow and outflow are essential for living related liver transplantation (LRLT). Preoperative delineation of those variations that would change the operative procedure to achieve a successful result especially in an emergency condition.

PURPOSE

Our aim was to develop a rapid and noninvasive imaging diagnostic method for the detection of anatomical variants that is mandatory for a safe operation when selecting potential liver transplant living donors. We used a different magnetic resonance (MR) imaging technique, which enabled to us to exploit the anatomical landmark of the liver, signal enhancement of blood flow in the abdomen, and the intrahepatic biliary routes inside the liver. Then, with the help of Advantage Window workstation reconstruction, the reconstructed single vascular or biliary systems were displaced in a three-dimensional fashion and the whole examination finished within 30 min.

METHODS

Modification of the standard MR technique was performed on a superconductive 1.5T whole body image scanner, MR arteriogaphy, venography, and cholangiography with three-dimensional reconstruction in evaluating the anatomy of the hepatic arteries, hepatic veins, portal venous system, bile ducts, and liver size in potential liver transplant living donors. These anatomical structures were compared with traditional imaging methods.

RESULTS

In all 38 cases, as well as delineation of the portal vein detail to the segmental level was satisfactorily obtained in this MR study. The images were well displayed in a three-dimensional fashion, which had good correlation with images from traditional imaging modalities and operative findings. In 86.8% cases, the MR arteriography was well matched with the celiac angiography. Of those 17 operative cases, estimation of liver volume was well correlated with the liver graft within 3.9-12.5% variation. In the major hepatic vein, we obtained 100% accuracy and 88.2% in the minor branches. Of 12 donors received intraoperative cholangiography during liver donation, good correlation of biliary anatomy was achieved. One donor was excluded from graft donation due to the complicated arterial supply to the left liver. According to the anatomical variation, surgical procedures in graft harvesting and anastomosis were readjusted and no major complications were found in those donors and all recipients survived after liver transplantation.

CONCLUSION

MR volumetry, venography, angiography, and cholangiography with three-dimensional reconstruction is sufficient for all major imaging evaluation. It may replace the traditional conventional catheter angiography, computed tomography, sonography and endoscopic retrograde cholangiography as a single investigation in the evaluation of the potential liver transplant donors. Angiography is only valuable in suboptimal cases and intraoperative cholangiography is only performed in biliary ductile variants.

N,N'-bis[4-(N-alkylamidino)phenyl]homopiperazines as anti-Pneumocystis carinii agents

The synthesis, anti-Pneumocystis carinii activity and DNA binding properties of eight new N,N'-bis[4-(N-alkylamidino)phenyl]homopiperazines are reported. Compounds 2 and 8 were the most potent and caused about 70% inhibition of Pneumocystis carinii growth in a cell culture model at 1 microM concentrations.

Serum cholesterol levels in mood disorders associated with physical violence or suicide attempts in Taiwanese

BACKGROUND

Many previous studies have discussed the relationships between serum cholesterol levels and depression, violence and suicide in Western countries. In this paper, the relationships between serum cholesterol levels and mood disorders, physical violence and suicide attempts in Taiwanese psychiatric inpatients were reported.

METHODS

A review of medical charts over a 1-year period was carried out in a population of 213 Taiwanese psychiatric inpatients that included 61 patients with affective disorders. The collected data included age, body weight, height, and serum cholesterol levels.

RESULTS

There were no significant differences in the serum cholesterol levels between patients with mania and major depression, between patients with and without physical violence, or between patients who had and had not made a suicide attempt using analysis of covariance after age or body mass index adjustment.

CONCLUSION

Due to the limitations of case numbers and study methods, the results need to be further clarified with larger numbers of patients and in controlled studies.

Neuroleptic malignant syndrome associated with long-term clozapine treatment: report of a case and results of a clozapine rechallenge

Clozapine has recently been found to be associated with neuroleptic malignant syndrome (NMS) after long-term treatment. Here, I report on a 34-year-old Taiwanese woman who had been diagnosed with schizophrenic disorder 17 years previously. She had received clozapine 250 mg/day monotherapy for 7 years. She had sudden onset of NMS signs with high fever, profuse diaphoresis, severe muscular rigidity, elevated creatine phosphokinase level and consciousness disturbance. Brain computed tomography, blood culture and cerebral spinal fluid studies were negative. She had no muscle rigidity and fever after treatment with normal saline 1500 ml/day and diazepam 30 mg/day for 8 days. On day 15, a rechallenge with clozapine was done with caution because the patient was experiencing auditory hallucinations and delusions of persecution. The dose was slowly increased to 250 mg/day over 18 days. She had no active psychotic symptoms or NMS again in the following year. I reported this case to remind readers of the possibility of induced NMS with long-term use of clozapine and successful clozapine rechallenge.

Interventional radiologic procedures in liver transplantation

Postoperative biliary and vascular complications contribute significantly to morbidity and mortality in liver transplantation. Interventional radiologists are an integral part of the multidisciplinary team necessary for optimizing the management of these complications. During a 15-year period, 39 cadaveric and 25 living related liver transplantations were performed at the Chang Gung Memorial hospital, Taiwan. Of 64 liver transplant recipients, 9 (3 adult and 6 pediatric) underwent 13 interventional radiological procedures for the treatment of biliary sludge-casts (n = 2), bile duct occlusion or stenosis (n = 2), hepatic veins thrombosis (n = 1), hepatic veins stenosis (n = 1), portal vein stenosis with splenorenal shunting (n = 1), biloma (n = 1), and infected fluid collection or ascites (n = 4). Antegrade or retrograde interventional approach was used to successfully treat all biliary complications, and all percutaneous drainage procedures were effective in the control of intra-abdominal fluid collections. Portal vein stenosis was treated by balloon dilatation, and the associated splenorenal shunt was closed by metallic coil embolization via transhepatic catheterization of the portal vein. Hepatic vein stenosis was effectively treated by balloon dilatation and expandable metallic stent deployment via transfemoral and jugular venous approaches, respectively. Hepatic vein thrombosis was only partially lysed by transvenous streptokinase administration, and surgical thrombectomy was needed to achieve complete recanalization. The total success rate of the interventional procedures was 92 % with no procedure-related complications. The overall survival rate in this series is 89 %, and all patients who underwent living related liver transplantation maintain to date a 100 % survival rate. We can conclude that interventional radiological procedures are very useful for managing biliary and vascular complications after liver transplantation. These techniques provide a cure in most situations, thus obviating the need for further surgical intervention or re-transplantation.

Nitrogen removal from wastewater by a catalytic oxidation method

The ammonia-containing waste produced in industries is usually characterized by high concentration and high temperature, and is not treatable by biological methods directly. In this study, a hydrophobic Pt/SDB catalyst was first used in a trickle-bed reactor to remove ammonia from wastewater. In the reactor, both stripping and catalytic oxidation occur simultaneously. It was found that higher temperature and higher oxygen partial pressure enhanced the ammonia removal. A reaction pathway, which involves oxidizing ammonia to nitric oxide, which then further reacts with ammonia to produce nitrogen and water, was confirmed. Small amounts of by-products, nitrites and nitrates were also detected in the resultant reaction solution. These compounds came from the absorption of nitrogen oxides. Both the minimum NO2- selectivity and maximum ammonia removal were achieved when the resultant pH of treated water was near 7.5 for a feed of unbuffered ammonia solution.

Assessment of donor fatty livers for liver transplantation

AIM

The effect of fatty liver on graft survival, especially with reference to macrovesicular and microvesicular steatosis, is still uncertain. This preliminarily study was designed to create a noninvasive method for the quantification of the hepatic fat content in vivo and to establish provisional criteria for the assessment of fatty donor livers before liver transplantation among transplant surgeons, radiologists, and pathologists.

METHODS AND MATERIALS

Different degrees of rat fatty liver model were established by feeding rats a diet deficient in choline and methionine for different periods of time. Computed tomography (CT) with test tubes containing variable percentages of fat equivalent substance were used to assess the severity of fatty change of the rat liver. This was then correlated with the histological classification, level of hepatic enzymes, and graft survival.

RESULTS

Linear correlation between the fat volume fraction added to the test tubes and CT density were found. The process of producing a fatty liver via diet alteration peaked at week 3. At this time hepatic enzymes, radiological fat content, and posttransplantation survival were worse (P=0.013), compared with other time points. Radiological assessment of fatty liver correlated well with survival and serum glutamic oxaloacetic transaminase and glutamic pyruvate transaminase levels.

CONCLUSION

Severe microvesicular steatosis does not influence recipient survival, however, macrovesicular steatosis affects graft survival. Caliber CT is a practical and simple method that allows an accurate noninvasive quantitative assessment of hepatic fatty infiltration. It has potential to be a useful parameter for the assessment of donor livers for clinical liver transplantation.

Biliary complications in living related liver transplantation

BACKGROUND

Biliary tract reconstruction has long been considered the Achilles' heel of liver transplantation as biliary complications can increase morbidity and mortality especially in partial liver graft transplantation.

METHODS

Thirty-four living related liver transplants were performed at Chang Gung Memorial Hospital in Kaohsiung for 33 children and 1 adolescent during a 5.5-year period. All potential donors underwent a detailed preoperative imaging study of the vascular and biliary anatomy, including three-dimensional helical computed tomographic cholangiography (n = 20), magnetic resonance cholangiography (n = 14), and intra-operative cholangiography (n = 31) before graft retrieval. All hepatic artery anastomoses were performed in the standard microsurgery fashion and their patency was confirmed intra-operatively using Doppler ultrasound.

RESULTS

The biliary complication rate was 8.8% (3/34), including multiple intrahepatic biliary stenosis of unknown origin (n = 1), bile leakage from the Roux-en-Y loop (n = 1), and a missed biliary radicle (n = 1) which were treated via interventional radiological and surgical procedures. The overall graft and patient survival rates were 100%.

CONCLUSION

The biliary complication rate in this series was low compared to those of other experienced centers. Complete study of the variations of intrahepatic duct ramification pre-and-intra-operatively provided adequate information on the appropriate transection plane. Furthermore, intra-operative Doppler ultrasound verification of vessel patency helps prevent vascular complications, which has been identified as a cause of biliary complications.

Outflow tract reconstruction in living donor liver transplantation

BACKGROUND

Hepatic venous reconstruction is critical in living donor liver transplantation because outflow obstruction may lead to graft dysfunction or loss. We describe our experience and analyze outcomes with a technique of creating a single outflow tract using venoplasties of the graft and recipient hepatic veins.

PATIENTS AND METHODS

A retrospective study was done on 38 consecutive living donor liver transplants performed from June 1994 to March 2000. The grafts included 36 left-side grafts and 2 right-side grafts. Nine grafts had multiple hepatic veins and required a venoplasty of two or three hepatic veins to create a single outflow orifice. Triple recipient hepatic venoplasty was performed in 32 patients, double venoplasty in 5 and none in 1.

RESULTS

There were four cases of outflow obstruction, three occurring in patients with a double recipient venoplasty. Two of the problems were remedied intraoperatively by adjusting the position of the graft although two were structural in nature and required the insertion of expandable metallic vascular stents. All donors and recipients with their original grafts are alive at a mean follow-up period of 27 months.

CONCLUSION

A triple recipient venoplasty with a matching venoplasty of multiple graft hepatic veins to create a single wide outflow orifice is recommended in living donor liver transplantation using left side grafts.

Removal of chlorophenols from aqueous solution by fly ash

Fly ash from coal-fired thermal power plants can be used for the removal of 2-chlorophenol (2-CP) and 2,4-dichlorophenol (2,4-DCP) with enthalpy changes of about -3 kcal/mol. The amounts of 2-CP and 2,4-DCP removed are affected by the pH value of the solution. The efficiency of removal improves when the pH value is less than the pK(a) values of 2-CP and 2,4-DCP, respectively. The adsorbed amount of chlorophenol by fly ash is also affected by particle diameter, carbon content, and the specific surface area of the ash used in this study. As expected, more adsorption takes place with fly ash of higher carbon content and larger specific surface area. Moreover, the adsorbed amount of chlorophenol is not influenced by the matrix in the wastewater, as shown by studying the removal of 2-CP and 2, 4-DCP in wastewater from a synthetic fiber plant. Chlorophenols in the wastewater were also removed efficiently through a fly ash column, with breakthrough times being inversely proportional to flow rates.

Minimal blood loss living donor hepatectomy

BACKGROUND

Donor hepatectomy with maximal safety while preserving graft viability is of principal concern in living donor liver transplantation. There are compelling reasons for avoiding blood transfusion, even with autologous blood, to avoid the potential risks it imposes on healthy donors. This study aims to describe the surgical technique and clinical outcomes of living donor hepatectomy with minimal blood loss requiring no blood transfusion.

METHODS

Donor hepatectomy was performed in 30 living donors according to a detailed preoperative imaging study of the vascular and biliary anatomy. Liver parenchymal transection was carried out with strict adherence to a meticulous surgical technique without vascular inflow occlusion to either side of the liver. Pre-, intra-, and postoperative data were gathered, and factors related to blood loss were analyzed retrospectively.

RESULTS

The intraoperative blood loss ranged from 20 to 300 ml with a mean of 72.0+/-58.9 ml (median, 55 ml), and neither homologous nor autologous blood transfusion was required in any of the donors intra- and postoperatively. All 30 donors were discharged with minimal complications, and remain well at a mean follow-up of 24 months after donation. Excellent graft viability was verified by the fact that all 30 recipients are alive and well with a few manageable complications. The actual graft and patient survival are both 100% at the time of writing.

CONCLUSIONS

Regardless of the extent of donor hepatectomy, blood loss can and should be kept to a minimum, and living donor hepatectomy without blood transfusion is a realistic objective.

Treatment of complicated hepatolithiasis with intrahepatic biliary stricture by ductal dilatation and stenting: long-term results

A group of 190 cases of hepatolithiasis with postoperative residual stones located proximal to the stricture sites were managed with the aim of complete clearance of stones and relief of bile stasis to decrease the potential risk of recurrence. All procedures were performed through a T-tube track with gradual dilatation and stent placement through the stricture sites, creating a channel that allows cholangioscopy and electrohydraulic lithotripsy. Complete clearance of intrahepatic duct (IHD) stones was achieved in 88.4% of cases. Multiple sharply angulated IHD strictures in right-sided hepatolithiasis constituted a major cause of failure. Recurrent stone formation and repeated cholangitis, subsequent drainage, and liver resection are associated with high mortality rates particularly if there is late development of a cholangiocarcinoma. We concluded that postoperative ductal dilatation and stenting through the T-tube track combined with endoscopic electrohydraulic lithotripsy is effective and safe for managing complicated hepatolithiasis. Persistent irreversible aneurysmal dilatation of IHD and atrophic change of the affected hepatic lobe at follow-up were ominous signs of recurrence and cholangiocarcinoma development. Early drainage with stone extraction combined with surgical intervention can prevent subsequent morbidity and mortality.

Repeated hypotensive episodes due to hepatic outflow obstruction during liver transplantation in adult patients

We report two cases of unusual repeated hypotension, decreased cardiac output, decreased mixed venous oxygen saturation, decreased central venous pressure, pulmonary artery pressure, and pulmonary wedge pressure after the completion of all vascular anastamoses of liver transplantation. These unstable hemodynamics appear to reflect a clinically relevant picture of hypovolemia. However, the real cause was partial hepatic outflow obstruction. The obstruction was suspected because hypotension was alleviated by elevating the full-sized liver graft ventrally and to the left. Doppler ultrasound examination confirmed that the flow velocity of the hepatic vein outflow was insufficient when the liver fell to its resting position in the right hepatic fossa. An additional side-to-side cavo-caval anastomosis resolved the problem in one patient, whereas the other required not only the additional anastomosis, but also application of a tissue expander filled with 770 mL normal saline beneath the liver to eliminate the obstruction. We emphasize that obstruction of the hepatic outflow causes only temporal hypovolemia because of a decrease of venous return and that treatment of this complication should be surgical intervention to relieve the obstruction. Blind resuscitation with fluids will not solve the problem and, in fact, may result in fluid overload with subsequent complications.

Treatment refusal: analysis of 15 cases

BACKGROUND

In this paper, we investigate the reasons for treatment refusal at Linkou and Kaohsiung Chang Gung Memorial Hospitals, and offer ways to improve the doctor-patient relationship.

METHODS

Cases were collected during a 2-year period according to the criterion of notification of "refused treatment" on consultation sheets, with a total of 1631 consultation sheets. All cases were discussed once a week in detail by psychiatrists and the consulting medical staff, and were followed up from 1 to 4 weeks. All cases were treated by the processes of informed consent and crisis intervention. The final results for the reasons of treatment refusal and psychiatric diagnoses were made by psychiatrists and the consulting medical staff.

RESULTS

The number of cases compatible with the criterion was 15 (10 men and 5 women). The reasons for treatment refusal included poor communication, inadequate information, lack of competency, denial and shock reaction, reappearance of the suffered experience, and autonomy of patients. The distribution of psychiatric diagnoses included 8 with major depressive disorders, 2 with delirium, 1 with schizophrenic disorder, 1 with adjustment disorder, 1 with acute stress disorder (post-traffic accident), 1 with alcohol dependence, and 1 was deferred. After adequate processes of informed consent and crisis intervention, 12 persons accepted medical treatment.

CONCLUSION

We should give patients adequate informed consent and crisis intervention to establish a good doctor-patient relationship and to respect the patients' autonomy for their choice of treatment.