Effect of Manganese Content on the Magnetic Susceptibility of Ferrous-Manganese Alloys: Correlation between Microstructure on X-Ray Diffraction and Size of the Low-Intensity Area on MRI

PURPOSE: There is an ongoing search for a stent material that produces a reduced susceptibility artifact. This study evaluated the effect of manganese (Mn) content on the MRI susceptibility artifact of ferrous-manganese (Fe-Mn) alloys, and investigated the correlation between MRI findings and measurements of Fe-Mn microstructure on X-ray diffraction (XRD). MATERIALS AND METHODS: Fe-Mn binary alloys were prepared with Mn contents varying from 10% to 35% by weight (i.e., 10%, 15%, 20%, 25%, 30%, and 35%; designated as Fe-10Mn, Fe-15Mn, Fe-20Mn, Fe-25Mn, Fe-30Mn, and Fe-35Mn, respectively), and their microstructure was evaluated using XRD. Three-dimensional spoiled gradient echo sequences of cylindrical specimens were obtained in parallel and perpendicular to the static magnetic field (B0). In addition, T1-weighted spin echo, T2-weighted fast spin echo, and T2*-weighted gradient echo images were obtained. The size of the low-intensity area on MRI was measured for each of the Fe-Mn binary alloys prepared. RESULTS: Three phases of alpha'-martensite, gamma-austenite, and epsilon-martensite were seen on XRD, and their composition changed from alpha'-martensite to gamma-austenite and/or epsilon-martensite, with increasing Mn content. The Fe-10Mn and Fe-15Mn specimens comprised alpha'-martensite, the Fe-20Mn and Fe-25Mn specimens comprised gamma+epsilon phases, and the Fe-30Mn and Fe-35Mn specimens exhibited a single gamma phase. The size of the low-intensity areas of Fe-Mn on MRI decreased relative to its microstructure on XRD with increasing Mn content. CONCLUSION: Based on these findings, proper conditioning of the Mn content in Fe-Mn alloys will improve its visibility on MR angiography, and a Mn content of more than 25% is recommended to reduce the magnetic susceptibility artifacts on MRI. A reduced artifact of Fe-Mn alloys on MRI is closely related to the paramagnetic constitution of gamma-austenite and/or epsilon-martensite.

Small Bowel Obstruction in Children: Usefulness of CT for Diagnosis and Localization

PURPOSE: To evaluate the usefulness of CT for the diagnosis of the cause and localization of small bowel obstruction. MATERIALS AND METHODS: Out of a group of children who underwent a CT examination for a suspected small bowel obstruction, 19 patients with confirmed underlying disorders were identified and included in the study. Neonates and patients with duodenal obstruction were excluded from the study. The CT findings were analyzed for the location of obstruction site, abnormalities of the mesentery and mesenteric vessels, bowel wall thickening, closed loop obstruction, and strangulation. The obstruction site was divided into five parts. The preoperative CT diagnosis was compared with the final diagnosis. RESULTS: Causes of small bowel obstruction were intussusception (n = 6), appendiceal perforation (n = 4), transmesenteric internal hernia (n = 2), postoperative bands (n = 1), idiopathic multiple bands (n = 1), a foreign body (n = 1), a small bowel adenocarcinoma (n = 1), Meckel's diverticulitis (n = 1), tuberculous peritonitis (n= 1) and Salmonella enteritis with bowel perforation (n = 1). The CT findings showed mesenteric vascular prominence (n = 13), omental or mesenteric infiltration (n = 10), localized bowel wall thickening (n = 7), closed loops obstruction (n = 3) and strangulation (n = 1). The obstruction site was identified in all cases. The causes of obstruction could be diagnosed preoperatively in 14 cases, but a preoperative diagnosis was difficult in 5 cases. CONCLUSION: The causes of small bowel obstruction in children are variable, and CT is useful for evaluating the cause and localization of small bowel obstruction.

A Study for Apoptosis and Its Mechanism of Allogeneic Activated T Lymphocytes Induced by Mouse Liver Immature Dendritic Cells

PURPOSE: Mouse liver nonparenchymal cells play an important role in the development of active apoptosis in graft- infiltrating cytotoxic T lymphocytes, and this apoptosis can be an explanation for liver graft acceptance. We intended to clarify whether immature mouse liver dendritic cells can induce apoptosis in allogeneic activated T cells and determine which mechanism is involved in this phenomenon. METHODS: A radiometric DNA fragmentation test ("JAM" assay) was used to determine whether mouse liver dendritic cells were able to induce activated T-cell apoptosis in vitro. In addition, immunohistochemical staining for Bax and Bcl-2 was examined to clarify whether Bax or Bcl-2 was involved in this apoptosis. RESULTS: Immature mouse liver dendritic cells were quite strong inducers of activated T cell apoptotic death in allogeneic mice in vitro (39.2+/-13.2% at E/T ratio=12.5/1) compared with spleen cells as effectors (4.7+/-13.4% at E/T ratio=12.5/1) (P<0.0001). By using immunohistochemical staining, we also showed that Bax might play some role in this phenonenon, but that Bcl-2 might not. CONCLUSION: Our data indicate that immature mouse liver dendritic cells might have a strong apoptotic activity toward activated T cells in allogeneic mice in vitro through a Bax-involved mechanism.

A Preliminary Gastric Emptying Study Using 99mTc-DTPA Scan after Pylorus-Preserving Pancreatoduodenectomy

PURPOSE: Pylorus-preserving pancreatoduodenectomy (PPPD) is an alternative surgical procedure for periampullary lesions. Early delayed gastric emptying is the most common and frustrating complication in the immediate postoperative period after PPPD and late delayed gastric emptying has been reported in some long-term follow-up studies. We evaluated the incidence of early delayed gastric emptying and analyzed temporal changes in gastrointestinal function after PPPD. METHODS: The incidence of early delayed gastric emptying was retrospectively evaluated from the medical records of 15 patients who underwent PPPD. Gastric emptying tests (GETs) using 99mTc-DTPA scan were performed on 11 of the patients every three months until 1 year, where possible. RESULTS: The incidence of early delayed gastric emptying was 6.7%. Five of the eight patients (62.5%) and six of the eight (75%) who underwent scintigraphy at 3 months and 6 months respectively, showed delayed gastric emptying. But at 12 months, all of the four patients who underwent GETs showed normal gastric emptyings. CONCLUSION: The incidence of early delayed gastric emptying after PPPD was 6.7%. Though there were few symptoms in long-term follow-up study using 99mTc-DTPA scan, delayed gastric emptying was frequently observed 3 to 9 months after PPPD. However, gastric emptying might be normalized in almost all patients around 1 year after PPPD.

Factors Affecting Osteoporosis Following Renal Transplantation

PURPOSE: Chronic renal failure is known to occur with many disturbances in calcium metabolism including osteoporosis, bone decalcification, osteitis fibrosa cystica, and parathyroid hyperplasia. Renal transplantation may benefit the patients with chronic renal failure by reversing these disturbances, but it can also have deleterious effects on the bone. Osteoporosis remains one of the most frequent and serious complications after renal transplantation. The aim of this retrospective study is to evaluate the factors affecting osteoporosis after renal transplantation. METHODS: Bone mineral density (BMD) was measured a median 46 months (range 1~121) after renal transplantation in 118 of 274 patients between March 1991 and May 2002. At the time of bone examination, sex, age, duration of dialysis before transplantation, posttransplantation period, cumulative doses of prednisone, number of rejection, serum levels of cyclosporine, BUN, Cr, Ca, P, alkaline phosphatase (ALP), osteocalcin, urine levels of deoxypyridinoline, and cumulative doses of prednisone were measured. RESULTS: Duration between renal transplantation and BMD measurement (Ed-confirm this addition) was longer, and cumulative doses of prednisone were higher in patients whose lumbar vertebrae BMD was osteoporotic with statistical significance (P=0.023 and P=0.011, respectively). Longer duration between renal transplantation and BMD measurement and higher cumulative doses of prednisone were also seen in patients whose femoral neck BMD was osteoporotic, but without a statistical significance (P=0.186 and P=0.184, respectively). Cyclosporine level did not correlate well with either lumbar vertebrae or femoral neck BMD (P=0.800 and P=0.474). Nor did other factors show a statistically significant correlation. CONCLUSION: Our data indicated that longer duration between renal transplantation and BMD measurement and higher cumulative doses of prednisone were the statistically significant factors affecting patients with osteoporotic BMD at the lumbar vertebrae and femoral neck. To prevent osteoporosis after renal transplantation, it is important to restrict the cumulative doses of prednisone as early as possible following renal transplantation.

Carcinoma of ampulla of vater with extensive invasion to the whole pancreas / 대한내과학회지

Carcinoma of ampulla of Vater is a papillary neoplasm arising in the last centi meter of the common bile duct (CBD) where it passes through the wall of the duodenum and ampulla of Vater. We report the case of an ampulla of Vater cancer with the characteristic extensive invasion to the whole pancreas. A 53-year old female was admitted to our hospital with chief complaint of epigastric pain, steatorrhea, and weight loss for 2 months. On physical examination, epigastric tenderness was detected. Gastroduodenoscopic biopsy from the mass revealed well differentiated adenocarcinoma. Abdominal CT demonstrated intraduodenal protruding mass with diffuse invasion to the whole pancreas. Arterial phase helical CT scan revealed intense heterogenous enhancement of entire pancreas. She underwent the Whipple procedure with total pancreatectomy. Final pathologic diagnosis was adenocarcinoma of ampulla of Vater with invasion of the whole pancreas and metastasis to the large number of regional lymph nodes.

Mast Cells in Renal Allografts

PURPOSE: Chronic rejection is the enemy in the battle for long term survival after renal allografts. Interstitial fibrosis is known to be the important finding in renal allografts with chronic rejection. Mast cells secrete a large number of fibrogenic factors and have been involved in chronic inflammation and tissue fibrosis. In this study the authors evaluated the relationship between mast cells and fibrosis in renal allografts with chronic rejection. METHODS: The authors evaluated 42 biopsied specimens of renal allografts. Immunohistochemistry using anti-mast cell tryptase (Dako, 1 : 200) and an LSAB kit (Dako) was applied to detect mast cells. The mean number of mast cells (MNM) per 10 high power fields was counted. RESULTS: MNM of implantation biopsies was 0.640+/-0.537, of acute rejection -1.969+/-1.216, of chronic rejection -6.0+/-3.133 (P0.05). CONCLUSION: Our data show that the number of mast cells in renal allograft was significantly associated with chronic rejection, donor sex and hypercholesterolemia.

A Case of Living Donor Liver Transplantation for Unresectable Hepatoblastoma / 대한소아혈액종양학회지

Hepatoblastoma is a rare pediatric malignancy which frequently presents at an advanced unresectable stage. Complete surgical resection after chemotherapy is the definitive treatment for hepatoblastoma. Liver transplantation should be considered for children who have unresectable hepatoblastoma. We report a case of a 18-month-old boy with unresectable hepatoblastoma who had transplantation with pre- and post-operative chemotherapy.

Native Ureterotransplant Ureterostomy for Ureteral Obstruction after Simultaneous Pancreas Kidney Transplantation

Significant surgical complications occur in about half of patients after simultaneous pancreas kidney transplantation (SPK) with bladder drainage. Urologic complications are very common in bladder-drained pancreas transplants. Urinary obstruction occurs in either the early or the late period following transplantation. Predictors of urological complications after transplantation have not been well established. Early obstruction is usually diagnosed by an increment of serum creatinine or through imaging studies, such as ultrasound and antegrade pyelogram. Surgical management is inevitable when conservative managements fails. If the length of the donor ureter is sufficient, it is possible to redo the ureteroneocystostomy. However, if this is not the case or the stricture is at a high level, a native ureterotransplant ureterostomy may be the procedure of choice. SPK was performed on a 36 year old male patient with insulin dependent diabetes mellitus and diabetic nephropathy. The pancreatic exocrine secretion was drained by duodenocystostomy. The patient developed an obstruction in upper ureter on the postoperative 16th day. On the postoperative 32nd day, a native ureterotransplant ureterostomy with a double J stent was performed. The postoperative course was uneventful. The double J stent was removed on postoperative 112nd day by cystoscope. A subsequent follow up showed excellent pancreatic and renal function.

Clinicopathologic Features of Early Recurrence Cases after Pancreatoduodenectomy in Periampullary Carcinoma / 한국간담췌외과학회지

BACKGROUND/AIMS: Periampullary carcinoma could recur early even after curative resection in the small-sized lesion. The aim of this study is to clarify the clinicopathologic features of early recurrence cases after pancreatoduodenectomy in periampullary carcinoma. METHODS: 15 cases (group I) of recurrence within 6 months after pancreatoduodenectomy were compared clinicopathologically with 17 cases (group II) of no recurrence until 2 years after pancreatoduodenectomy between 1991 and 2000 in Hallym medical center. RESULTS: There were no differences in sex and age distri- butions between two groups (M/F ratio=8/7 vs 8/9, and average age=56.9 vs 57.5). The distributions of primary lesions were 4 cases of ampulla of Vater, 6 cases of common bile duct, 5 cases of pancreatic head in group I; 7 cases of ampulla of Vater, 8 cases of common bile duct, 2 cases of pancreatic head in group II, respectively. There were no differences in tumor size (2.8+/-1.1 cm vs. 2.4+/-1.5 cm), the number of lymph node metastasis, AJCC tumor stage, histological differentiation, neural or lymphatic invasion between two groups. The number of direct invasion to adjacent organs in group I was more than that in group II (p<0.05). CONCLUSION: The increased number of direct invasion to adjacent organs could be an important prognostic factor of early recurrence after pancreatoduodenectomy even in small-sized or no lymph node-metastasized periampullary carcinoma.

Characteristics of Adult-Onset Choledochal Cyst

PURPOSE: Choledochal cyst is a rare disease associated with an anomalous junction of the pancreaticobiliary ductal system (AJPBDS). We intended to demonstrate the characteristics of adult-onset choledochal cyst retrospectively. METHODS: ERCP findings of nineteen adult cases of choledochal cyst were compared with those of nine normal persons, in respect to the length and diameter of the common channel, and the angle of the pancreaticobiliary ductal junction. RESULTS: Patients of adult-onset choledochal cyst displayed a long, ectatic common channel and a larger angle of the pancreaticobiliary junction (p<0.05). All patients except one had AJPBDS. Thirteen patients were classified as Todani type Ia, one as type Ic and five as type IVa. Fourteen patients were classified as choledochopancreatic (C-P) type, two as pancreaticocholedochal (P-C) type, and three were unclassified by Kimura's classification. Sixteen patients were compatible with cystic type and three with cylindrical type by Okada's classification. Among the three cylindrical type patients two of them were classified as P-C type and one as C-P type. Histologically cystic type patients showed mild glandular or fibrotic patterns, however cylindrical type patients tended to show the severe glandular pattern. CONCLUSION: Adult-onset choledochal cyst was closely related with AJPBDS, although the reflux of pancreatic juice due to AJPBDS would not be the only cause to determine the morphology of adult-onset choledochal cyst. The meaning of this tendency toward a severe glandular pattern in cylindrical type patients requires elucidation.

Liver Non-Parenchymal Cells Induce Apoptosis in Activated T Cells in Vitro / 대한이식학회지

PURPOSE: Liver, unlike heart or skin, allografts transplanted between MHC-disparate mouse strains are spontaneously accepted without any immunosuppressive therapy. Despite the allograft acceptance, the recipients continue to exhibit donor-specific immune responses in vitro (MLR and generation of CTL). High levels of CTL apoptosis evident within tolerated liver grafts have been postulated as a mechanism underlying this 'split' tolerance. METHODS and RESULTS: By using radiometric DNA fragmentation test ("JAM" assay) and TUNEL staining, we present the evidence here that liver nonparenchymal cells (NPC) are quite strong inducers of activated T cell apoptotic death in allogeneic mice. This phenomenon occurs the similar level in activated T cells of syngeneic or third-party mice. Liver cells from gld (FasL-deficient) mice exert similar apoptosis-inducing effect on activated T cells from normal mice. Tumor necrosis factor receptor (TNFR): Fc fusion protein, and concanamycin A, an inhibitor of perforin pathway, fail to inhibit the apoptotic activity. CONCLUSION: These data indicate that liver NPC play important role in causing active apoptosis in graft-infiltratingCTL which favors liver graft acceptance, and liver-induced activated T cell apoptosis may not mediated by Fas, TNF or perforin pathways.

Two cases of Mirizzi syndrome / 한국간담췌외과학회지

Impaction of a gallstone in the cystic duct or neck of the gallbladder can cause partial hepatic duct obstruction. Mirizzi originally described the syndrome of obstructive jaundice presented in the patient with gallstone in 1948. Cholecystobiliary fistula is a complicated form of Mirizzi syndrome in longstanding cholecystitis. A 70 year-old female was admitted due to jaundice. On laparotomy, the right heaptic duct was compressed by distended gallbladder. The other 60 year-old male patient was referred with jaundice. The patient underwent laparoscopic cholecystectomy two years ago. A large stone was migrated from remnant cystic duct through a cholecystocholedochal fistula. We report two cases of Mirizzi syndrome with a review of literature.

A Case of Choledochal Web / 한국간담췌외과학회지

A web arising in the bile duct is a rare disease. Most cases are found at operation or autopsy becasue of the rare incidence and absence of specific clinical manifestations. However, early diagnosis has been feasible with the development of radiologic studies. We report a case of choledochal web with a review of the literature.

Two Cases of Acute Mesenteric Infarction Due to Superior Mesenteric Arterial and Venous Branch Occlusion

Acute mesenteric infarction is a catastrophic illness representing a diverse spectrum of pathologic conditions which ultimately lead to necrosis of the intestine and which is uniformly fatal if left untreated. Despite better understanding of the disease process, acute mesenteric infarction continues to be a lethal disorder with high mortality rate. We experienced two cases of acute mesenteric infarction due to superior mesenteric arterial and venous branch occlusion, respectively, in recent years: One case was focal segmental ischemia with normal radiologic finding including angiography, successfully treated with segmental resection of the necrotized ileum, another case was mesenteric venous thrombosis, also treated with resection of necrotized small intestine followed by second look operation.

Pulmonary Infection after Kidney Transplantation / 대한이식학회지

The infectious complications after renal transplantation remain as an important causes of both mortality and graft loss. The lung is the most common target for post-transplant infection. We analyzed the causative agents, treatments and outcomes of post-transplant pulmonary infections. From 1990 to 1998, 192 renal allografts were performed at Hallym University Hospital. Seven cases (3.6%) of 5 males and 2 females developed serious pulmonary infections and required hospitalization. The mean age was 42.6 years. The onsets of pulmonary infections were from a month to 6 months in 3 cases, from 6 months to a year in one case and after a year in 3 cases. Triple therapy regimen was used in 4 cases as an immunosuppression therapy. Acute rejections developed in 6 cases. Causative organisms were Cytomegalovirus in 2 cases, Mycobacteria in 2 cases, Aspergillus in a case, Nocardia in a case and unknown in a case. Despite appropriate antibiotics, four patients did not respond to the treatment and died. The early recognition of infection and appropriate therapy is important to reduce fatal consequence.

Clinical Experience of Kidney Transplantation in the Hallym University Hospital / 대한이식학회지

Renal transplantation has been adopted as the treatment of choices for most patients with a end stage renal disease. This is the presentation of our experience of renal transplantation at Hallym University Hospital. From March 1984 to July 1998, 207 cases of renal transplantations were performed, 15 cases out of which were lost during follow-up period and excluded from the study. The mean age of recipients was 37.1 years. The male to female ratio was 1.5:1. Eighty nine renal allografts (46.4%) were from living unrelated donors, 59 (30.7%) from living donors and 44 (22.9%) from cadaveric donors. As an immunosuppression theray, a triple regimen was used in 104 cases (54.2), a double regimen in 86 (44.8%) and a single regimen in one (0.5%). The overall rejection developed in 87 cases (45.3%). The rejection rate was 59.3% in renal allografts from living related donors, 37.1% from living unrelated donors and 43.2% from cadavaric donors. The OKT3 and the antilymphocyte globulin (ALG) were used for steroid resistent rejection in 8 and 2 cases, respectively. Post-transplant diabetes mellitus were noticed in 22 cases (11.5). The most common complication was infection (28.1%), and 11 recipeints (5.7%) died during follw-up period. Infection was the leading cause of mortality. The overall graft survival was 92.2% at 1 year span and 83.1% at 3 year span. The overall patient survival was 95.6% at 1 year span and 92.5% at 3 year span.

Liver Resection under Total Vascular Occlusion for Hepatoma in Contact with Hepatic Vein or Inferior Vena Cava / 한국간담췌외과학회지

Total vascular occlusion (TVO) of the liver was used during parenchyma resection in two patients with large hepatoma located near hepatic vein or inferior vena cava. This technique was achieved by clamping the porta hepatis as well as suprahepatic and infrahepatic IVC. Durations of TVO were 15 and 25 minutes respectively. Three and four units of packed RBC were transfused for each patient. Postoperative hepatic or renal failure did not occur. The technique of TVO is easy and safe for resection of large and critically located tumors that would otherwise present operative risk.

A Case of Liver Transplantation using a Jump Graft in a Patient with Portal Vein Thrombosis and Postoperative Chylous Ascites

Venous anomalies, including portal vein thrombosis (PVT) and prior portosystemic shunts, are not uncommon in orthotopic liver transplantation (OLT) and require vascular reconstruction. PVT has been considered as a contraindication to OLT because of surgical complexity and increased postoperative morbidity and mortailty rates. Postoperative chylous ascites occur following disruption of abdominal lymphatics after retroperitoneal dissection. Chyloperitoeum after OLT is very rare. We report a case of piggyback OLT in a cirrhotic patient with portal vein thrombosis. A thromboendarterectomy was attempted first, and a venous jump graft was required between the donor portal vein and the infrapancreatic superior mesenteric vein. An aortic conduit was used for the hepatic arterial reconstruction. Retroperitoneal dissection was inevitable. Chylous ascites developed after the operation and were managed successfully with a low-at diet. In conclusion, we suggest that the presence of PVT is not a contraindication for OLT. Chylous ascites are rare after OLT, and the treatment of choice is a conservative one based on diet control.

Clinical Analysis of PTFE Graft Arteriovenous Fistula: The long-term patency rate and factors affecting the patency rate

Expanded polytetrafluoroethylene(PTFE) graft fistulas are widely used as secondary vascular access for patients receiving long-term hemodialysis. It is well known also that several factors should be considered in order to maintain PTFE graft fistula adequately. To elucidate these factors, we reviewed 71 cases of PTFE graft arteriovenous fistula that performed at Hallym University Hospitals from March 1991 to December 1995 and analysed it for regard to age, serum creatinine level, diabetes mellitus, hypertension, diameter of graft and operation site and method. The resultes were as follows: 1) The mean duration of patency of PTFE graft fistula was 10month and the 6 month, 12 month and 24 month patency rate was 64.9%, 39.4% and 36.1% respectively. 2) The complication rate was 45%. 3) Of these factors, diabetes mellitus was the only factor that decreased the patency rate(P<0.05).