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O T Terpstra

Publications and source records attributed to O T Terpstra.

At least 19 recordsLinked to original sources
PubMed1992

[Percutaneous bile duct drainage; experiences with a new type of endoprosthesis].

Self expandable stents were placed percutaneously in 105 patients with malignant biliary obstruction. Stent diameter was 1 cm; length, 3.5-10.5 cm. Of the 60 patients with common bile duct obstruction, 50 died 0.2-12 months (median 3 months) after stent insertion. Two patients developed recurrent jaundice and cholangitis after 6 and 12 months, respectively. One patient underwent reintervention. Ten patients, one after a successful reintervention, were alive without jaundice 1-8 months (median 5 months) after stent placement. Of the 45 patients with hilar lesions, 26 died 0.7-18 months (median 5 months) after stent placement, five of them with signs of cholangitis. Nineteen are alive 1-21 months (median 7 months) afterwards. Reinterventions were carried out in 13 patients (29%). The most common cause of stent malfunction was tumour overgrowth. Stent-related complications were seen in three patients.

Adult↗
PubMed1992

[3-year results of 'gallstone outpatient clinic' in an academic hospital].

On April 1st 1988 an outpatient clinic solely for patients with gallstones was started. 594 patients visited the gallstone outpatient clinic during the first three years of its existence and the data of all these patients were collected and examined retrospectively. Mean age was 49.0 years (SD: 15; range: 20-88), male-female ratio was 0.34 and the majority of patients were symptomatic (86.9%). 60.3% were referred by their general practitioners, 21.7% by another specialist en 18.0% sought help on their own initiative. In 8.1% of the cases there were acute biliary problems and 2.4% had an increased surgical mortality risk. Cholecystectomy was advised in the majority of patients (51.9%), expectant management in 20.2%, analysis was stopped in 2.5% and the others (25.4%) were advised a treatment alternative to cholecystectomy. Medical, but most of all public interest in the different therapeutic modalities for symptomatic cholelithiasis has a trend-sensitive character which is reflected in patterns of referral, diagnostic procedures and therapeutic advice given.

Academic Medical Centers↗
PubMed1992

Graft regeneration and host liver atrophy after auxiliary heterotopic liver transplantation for chronic liver failure.

We studied the size of the liver graft and the host liver in six consecutive patients undergoing auxiliary heterotopic liver transplantation for chronic end-stage liver disease. In all cases, a liver reduced in size by left lateral hepatectomy was inserted. The sizes of the graft and host liver were estimated by planimetry of two-dimensional di-isopropyl iminodiacetic acid scintigrams taken 3, 7, 21, 90 and 180 days after surgery. Graft size increased from a mean of 12.2 cm2 (95% confidence interval = 10.2 to 14.1) on day 3 to a maximum of 14.8 cm2 (95% confidence interval = 13.4 to 16.1) on day 21 and remained stable thereafter; in contrast, the host liver decreased in size from 9.6 cm2 (95% confidence interval = 6.8 to 12.3) on day 3 to 3.9 cm2 (95% confidence interval = 3.0 to 4.8) at mo 6. We conclude that in patients with chronic liver failure, an auxiliary allograft reduced in size and placed adjacent to the host liver shows regenerative growth within 3 wk, whereas the host liver atrophies in 3 to 6 mo.

Adult↗
PubMed1992

Increased tissue-type plasminogen activator activity in orthotopic but not heterotopic liver transplantation: the role of the anhepatic period.

The major cause of the increased tissue-type plasminogen activator activity during orthotopic liver transplantation is still unclear. Both the lack of hepatic clearance of tissue-type plasminogen activator in the anhepatic period and increased endothelial release from the graft on reperfusion have been proposed as the major causes. Heterotopic liver transplantation avoids the resection of the host liver and is a useful model to help differentiate between these two possibilities. In this study the fibrinolytic system was evaluated in 10 orthotopic liver transplantations, 18 heterotopic liver transplantations and a control group of 10 partial hepatic resections. A marked increment in tissue-type plasminogen activator activity, from 0.2 to 5.2 IU/ml (p less than 0.02), was observed during the anhepatic period of orthotopic liver transplantation, which rapidly normalized after reperfusion. In contrast, tissue-type plasminogen activator activity levels remained normal in heterotopic liver transplantation and partial hepatic resections. In orthotopic liver transplantation and in heterotopic liver transplantation no increase occurred in tissue-type plasminogen activator activity after reperfusion. The first venous hepatic outflow after reperfusion did not contain elevated tissue-type plasminogen activator activity levels. Plasma degradation products of fibrin and fibrinogen increased during the anhepatic period of orthotopic liver transplantation (from 2.60 to 8.80 micrograms/ml [p less than 0.008] and from 0.40 to 1.60 micrograms/ml [p less than 0.04], respectively) and remained elevated thereafter. In heterotopic liver transplantation and partial hepatic resections these levels remained low. In conclusion, the lack of hepatic clearance during the anhepatic period is probably the most important factor in the evolution of increased tissue-type plasminogen activator activity during orthotopic liver transplantation.

Blood Transfusion↗
PubMed1992

New aspects of heterotopic liver transplantation.

In this report the history and clinical results of heterotopic liver transplantation (HLT) are reviewed and some special aspects of current research on HLT are high-lighted. The first laboratory experiments on liver transplantation were performed with auxiliary heterotopic grafts. The initial clinical results of HLT, however, were disappointing and orthotopic liver transplantation (OLT) evolved to be the procedure of choice. Of all the patients who received a heterotopic graft before 1980, only two survived. Since 1980, 50 HLTs are known to have been performed on 48 patients. Results of HLTs after 1986 are clearly better than earlier ones, and survival rates come within the range of those reported for OLT. Intraoperative fibrinolysis is found in the anhepatic phase of OLT, something which is absent in HLT. Tissue-type plasminogen activator (t-PA) is said to be responsible for this phenomenon, as well as for the postreperfusion hyperfibrinolysis. Parallel to the hemostatic changes, the intraoperative hemodynamic stability may be impaired by deleterious substances that arise during liver transplantation. Furthermore, the interaction between the two livers, the effect of HLT on portal pressure and hypersplenism, and the possible role of HLT in inborn errors of hepatic metabolism are described. Special attention is given to the treatment of acute hepatic failure. OLT, in an early phase of the disease, negates the possibility of spontaneous recovery, while delay of the decision to transplant may lead to further deterioration of the patient's clinical condition. As the procedure of HLT is reversible, the decision to transplant can be made more quickly. The clinical experience with HLT for acute liver failure is reported in detail.

Fibrinolysis↗
PubMed1992

Selective accumulation of endogenously produced porphyrins in a liver metastasis model in rats.

The possibility of using the porphyrin precursor 5-aminolevulinic acid to cause selective porphyrin accumulation in tumors was examined. Syngeneic colon carcinomas CC531 were implanted in the livers of Wag/Rij rats. Groups of three to six animals each were given 2 mg/mL of 5-aminolevulinic acid in drinking water from the 8th, 14th, or 17th day after tumor implantation. Two other groups received either 2.5 or 5 mg/kg of Photofrin II (Photomedica Inc., Raritan, NJ) intravenously on day 17. On day 19 the livers were removed and porphyrin concentrations were measured in normal livers and tumors by solvent extraction and high-performance liquid chromatography. Protoporphyrin accumulated progressively in tumors with increasing duration of 5-aminolevulinic acid administration (P = 0.0001), whereas no increase was found in normal livers. After 11 days of 5-aminolevulinic acid administration the porphyrin concentration ratio between tumors and livers was 4:1. In contrast, after Photofrin II administration the concentration was higher in normal livers than in tumors (1:3 ratio, tumor to liver). Enzyme measurements showed a threefold decrease in ferrochelatase activity in tumors compared with livers (P less than 0.001). In conclusion, oral administration of 5-aminolevulinic acid results in progressive accumulation of protoporphyrin in a transplantable colon carcinoma without accumulation in the surrounding liver tissue. This selective accumulation of porphyrins appears to be caused by a relative ferrochelatase deficiency in malignant tissue. 5-Aminolevulinic acid administration may be a suitable approach to photosensitizing liver tumors for photodynamic therapy or to early detection of tumors by fluorescence in ultraviolet light.

Aminolevulinic Acid↗
PubMed1992

Treatment of experimental liver metastases with a noncontact neodymium: YAG laser.

The extent of tumor and liver damage after treatment with the neodymium:yttrium-aluminum-garnet (Nd:YAG) laser was investigated in a rat tumor model. Colon carcinoma CC531 was implanted in the liver and treated with 60 J (14 tumors), 120 J (15 tumors), or 180 J (12 tumors) at a power setting of 20 W. To assess the effects upon the tissues three animals were sacrificed immediately after treatment and 1, 2, 4, and 8 days later. Sections from the tumor sites were evaluated by light microscopy and the maximal depth and width of different zones of tissue damage were measured. Laser effects could be determined most accurately on Days 1 and 2 after treatment. Multiple linear regression analysis of the data indicated a linear relationship between laser energy and depth of tumor damage (P less than 0.01). The results of this study show the potential of the Nd:YAG laser to produce tumor coagulation necrosis with minimal liver necrosis.

Aluminum↗
PubMed1992

Course of hepatitis B and D virus infection in auxiliary liver grafts in hepatitis B-positive patients. A light-microscopic and immunohistochemical study.

Four patients who received an auxiliary partial liver graft for decompensated liver cirrhosis due to hepatitis B (HBV), associated in two cases with hepatitis D virus (HDV) superinfection, were studied. The sequential appearance of hepatitis B and D antigens in the grafts was investigated in serial liver biopsies by immuno-histochemical methods and compared with the viral antigenic profiles of the host livers. The histological changes in the liver grafts were studied in relation to the viral expression patterns. One week after transplantation, expression of HBsAg was already apparent in two grafts. HBcAg was found in the graft of the only patient with HBcAg in the host liver. HDAg was expressed in the grafts of both patients with HDV superinfection; in one of these cases HDAg was present without HBsAg. At 3 months, viral antigen expression was maximal. Expression of HBsAg and HBcAg in the grafts of the two HDV-positive patients was, however, less extensive than in the two HBV-positive patients. All patients developed a mild lobular hepatitis, histologically demonstrated between the 47th and 107th posttransplantation day. In the two HBV-positive, HDV-negative patients, cirrhotic transformation of the graft occurred within 1 year. In the HDV-positive patients only a mild chronic active hepatitis with slight or moderate fibrosis was observed after 1 year. We conclude that recurrence of HBV and HDV infection in auxiliary liver grafts is demonstrable within 1-3 weeks. HBV infection in liver grafts may be a rapidly progressive disease. Coinfection with HDV does not aggravate the acute hepatitis and may even suppress the progression of chronic HBV.

Adult↗
PubMed1992

Interstitial photodynamic therapy in a rat liver metastasis model.

Photodynamic therapy (PDT) of hepatic tumours has been restricted owing to the preferential retention of photosensitizers in liver tissue. We therefore investigated interstitial tumour illumination as a means of selective PDT. A piece of colon carcinoma CC531 was implanted in the liver of Wag/Rij rats. Photofrin was administered (5 mg kg-1 i.v.) 2 days before laser illumination. Tumours with a mean (+/- s.e.) diameter of 5.7 +/- 0.1 mm (n = 106, 20 days after implantation) were illuminated with 625 nm light, at 200 mW cm-1 from a 0.5 cm cylindrical diffuser and either 100, 200, 400, 800 or 1600 J cm-1. Control groups received either laser illumination only, Photofrin only or diffuser insertion only. Short-term effects were studied on the second day after illumination by light microscopy and computer-assisted integration of the circumference of damaged areas. Long-term effects were studied on day 36. To determine the biochemistry of liver damage and function, serum ASAT and ALAT levels were measured on day 1 and 2, and antipyrine clearance on day 1. Tumour and surrounding liver necrosis increased with light dose delivered (P < 0.001). Best long-term results were obtained at 800 J cm-1 with complete tumour remission in 4 out of 6 animals. No deterioration in liver function was found. The results of this study show the ability of interstitial PDT to cause major destruction of tumour tissue in the liver combined with minimal liver damage.

Adenocarcinoma↗
PubMed1992

Evidence of metabolic activity of adult and fetal rat hepatocytes transplanted into solid supports.

This study was undertaken to assess the metabolic effect of fetal and adult hepatocyte transplantation in the Gunn rat, genetically incapable of bilirubin conjugation. A comparison was made between fetal and adult hepatocytes transplanted into the spleen, and those injected into polytetrafluoroethylene (PTFE) solid supports that had previously been implanted intraperitoneally. Between 4 and 12 weeks after intrasplenic transplantation of adult liver cells, serum bilirubin was significantly decreased when compared with control animals (39.6 +/- 5.6%; P less than 0.01 vs. controls). Intrasplenic transplantation of fetal hepatocytes resulted in a maximal decrease of 33.2 +/- 9.1% at 8 weeks postoperatively (P less than 0.02 vs. controls). Similar declines of serum bilirubin levels were found after transplantation of adult or fetal liver cells into the solid supports. At 12 weeks after transplantation, bilirubin conjugates were detectable in the bile of all animals that underwent intrasplenic hepatocyte transplantation and in 60% of those that underwent the solid support procedure, whereas none could be detected in control animals. Histological evidence of surviving cells was obtained in all but one animal at 12 weeks, and confirmed at 12 months postoperatively. It is concluded that the PTFE solid support technique offers an attractive alternative to the intrasplenic route, and that both fetal and adult hepatocytes, transplanted in either way still exert their conjugating activity after 12 weeks.

Animals↗
PubMed1992

The effects of long-term graft preservation and prostaglandin E1 on intraoperative hemodynamic changes in liver transplantation. A comparison between orthotopic and heterotopic transplantation in the pig.

The study aimed to compare the intraoperative hemodynamic changes during orthotopic liver transplantation (OLT) with those during heterotopic liver transplantation (HLT) after different durations of cold storage of the graft. The effect of prostaglandin E1 (PGE1) on these parameters was also studied. Sixty-nine female Yorkshire pigs underwent either OLT (n = 32) or HLT (n = 37) with a graft stored for 2 hr (n = 31), 24 hr (n = 16), 48 hr (n = 7), or 72 hr (n = 15). In 16 transplantations in the various groups, PGE1 was given intravenously to both donor and recipient animals and it was added to the preservation and flushing solutions. Univariate nonparametric tests (Mann-Whitney and Wilcoxon rank-sum) were used for analysis of cardiac output (CO), mean arterial pressure (MAP), left and right ventricular minute work (LVMW, RVMW), pulmonary capillary wedge pressure (PCWP), and systemic and pulmonary vascular resistance (SVR, PVR), at different intervals during the operative procedure. For the three main variables--i.e., the type of transplantation, the use of PGE1, and the preservation time, multiple regression analysis was performed. During HLT, portal vein clamping lowered MAP and CO, while during the anhepatic phase in OLT, SVR increased and CO dropped. After recirculation of the graft, an increase in PVR and a decrease in SVR were found in both OLT and HLT. At different stages of the surgical procedure, longer graft storage time diminished CO and MAP (P less than 0.001), especially in OLT. PGE1 appeared to reduce the cardiovascular reserves needed to compensate the changes after recirculation of the graft. The observed differences in intraoperative hemodynamics between OLT and HLT can partly be attributed to differences in operative techniques. Extension of the graft preservation period resulted in poor cardiac performance, more so in OLT than HLT. The native liver in HLT might be able to metabolize the presumed myocardial depressant factors, released by the graft upon reperfusion. Prostaglandin E1 did not protect against the reperfusion syndrome.

Alprostadil↗
PubMed1992

Accuracy of ultrasound and oral cholecystography in assessing the number and size of gallstones: implications for non-surgical therapy.

Prior to non-surgical therapy of gallstones it is important to assess their number and size. In order to evaluate the accuracy of ultrasound (US) and oral cholecystography (OCG) in counting and measuring gallstones, a prospective blind study was conducted to compare the results of US (n = 99) and OCG (n = 36), either alone or in combination (n = 34), with the number and size of gallstones retrieved after cholecystectomy. The number of gallstones was accurately estimated by US and OCG in 74% and 69% of the cases, respectively. In assessing the presence of up to three, five or 10 gallstones both US and OCG proved reliable. In measuring the size of gallstones, there was 19% accuracy with US compared with only 3% with OCG. With an accepted measurement error of 3 mm these values increased to 80% for US and 44% for OCG. US proved more reliable than OCG in discriminating gallstones smaller or larger than 10 mm and smaller or larger than 20 mm, but with US, detection of gallstones larger than 30 mm was problematic. Both US and OCG underestimated gallstone size. The combination of both techniques did not significantly improve the assessment of either number or size of gallstones compared with the results obtained with US or OCG alone. It is concluded that (1) both US and OCG have some limitations in assessing the number and size of gallstones, (2) the combination of both examinations does not improve accuracy, and (3) patient selection for non-surgical treatment of gallstones can be started by US alone.

Adult↗
PubMed1992

Electromagnetic shock wave lithotripsy of gallbladder stones: a wide range of inclusion criteria.

From April 1988 until November 1990, 83 patients with symptomatic gallbladder stones were treated in the University Hospital "Dijkzigt" Rotterdam with extracorporeal shock wave lithotripsy (ESWL) followed by oral administration of bile acids (urso- and chenodeoxycholic acid). According to our inclusion criteria, patients with up to 10 stones without any limit to the size of the stone(s) were accepted for treatment. On average, these patients underwent two sessions of ESWL with an electromagnetic lithotriptor (Lithostar and Lithostar Plus, Siemens AG, Erlangen, Germany). Fragmentation of stones was achieved in 70/83 (84% patients). The best results were achieved in patients with a solitary gallstone (50% of these patients were stone-free 12 months after ESWL). Four percent of the patients with two to three stones, and 12% of the patients with four to 10 stones were free of stones 12 months after ESWL. Twenty-eight (34%) patients suffered from biliary colics after ESWL, and three patients (3.5%) developed pancreatitis. The administration of oral bile acids was complicated by transient diarrhoea in 15 (18%) patients. ESWL followed by oral bile acid therapy is a relatively effective and safe therapy for a highly select population of patients with gallbladder stones, which can be performed on an outpatient basis. Although the results for multiple stones were poor, the usage of wide inclusion criteria (up to 10 stones of any size) did not affect the success rate of ESWL for multiple stones.

Adult↗
PubMed1991

[Favorable results of auxiliary heterotopic liver transplantation in patients with end-stage chronic liver insufficiency].

Auxiliary heterotopic liver transplantation (HLT), which avoids removal of the host liver, may improve the results of liver transplantation in patients with end-stage chronic liver disease. However, the results of HLT have so far been disappointing. In 1986 a program of HLT was started in the University Hospital Rotterdam-Dijkzigt. Eighteen patients with chronic liver failure underwent HLT. Twelve out of 18 (67%) patients were discharged 25 days after transplantation with normal liver function. Six patients died within 3 months after operation due to septic causes. Three months after transplantation ascites was no longer detectable and oesophageal varices had disappeared in all surviving recipients of HLT. The actuarial 3 and 12 months survival rate was 67%. Hepatitis B virus reinfection was seen in all patients. In two patients cirrhosis of the graft developed within one year. These data suggest that HLT in patients with chronic liver failure gives long-term metabolic support and adequate decompression of portal system, and is associated with a morbidity and mortality comparable to that of orthotopic liver transplantation.

Adult↗
PubMed1991

[Liver transplantation in acute liver insufficiency: definitive replacement or auxiliary liver?].

Orthotopic liver transplantation (OLT) has greatly improved the chances of survival in patients with acute hepatic failure. However, this mode of treatment requires lifelong immunosuppressive medication and negates the potential recovery of the host liver. In theory, auxiliary heterotopic liver transplantation (HLT) offers the diseased host liver a chance to regenerate, so that immunosuppression can be tapered off and eventually stopped. In the University Hospital Rotterdam Dijkzigt OLT and HLT were performed in two patients, with acute and subacute hepatic failure respectively. The patient undergoing OLT recovered quickly but needed a successful re-OLT after a serious rejection episode. The removed diseased liver showed no signs of regeneration at histology. The patient undergoing HLT also recovered well. HIDA scanning as well as liver biopsies of the host liver and the grafted liver 1 and 6 months after transplantation indicated full recovery of the host liver, so that immunosuppression is being tapered off.

Adult↗