Mikio Masuda

Transcatheter coil embolization of an iatrogenic superior mesenteric arteriovenous fistula: Report of a case

A 37-year-old male patient presented with abdominal pain and diarrhea. Computed tomography showed a large superior mesenteric vein aneurysm. The patient had a history of Crohn’s disease and underwent an ileocecal resection 7 years previously. A selective angiogram of the superior mesenteric artery revealed that a dilated branch of this artery fed directly into the superior mesenteric vein. The iatrogenic superior mesenteric arteriovenous fistula was successfully closed by transarterial coil embolization. Successful endovascular treatment for a superior mesenteric arteriovenous fistula has been recently reported; however, the complications of this new modality are not well understood. We herein review the current literature and discuss endovascular treatment.

A technique using a rectus abdominis muscle flap in the treatment of adult congenital tracheoesophageal fistulas

The authors successfully treated an adult with congenital tracheoesophageal fistula (TEF) Gross-C type by the addition of an effective pedicled muscle flap. This patient had undergone 2 thoracotomies when he was an infant at another hospital; however, the fistula recurred. After transection and closure of the fistula, a right rectus abdominis muscle flap between the 2 stumps was interposed. The current case followed a favorable postoperative course; neither fistula nor abdominal hernia occurred.

Clinical study of biocompatibility between open and closed heparin-coated cardiopulmonary bypass circuits.

The objective of this study was to investigate the difference between the closed circuit system and the open circuit system in clinical heparin-coated cardiopulmonary bypass (CPB) circuits with a centrifugal pump. We evaluated the coagulation, fibrinolysis, and inflammatory response in valvular heart surgery. Nineteen patients were assigned at random to a group for the closed circuit system or the open circuit system. This is the first report on the effect of a closed circuit in valvular surgery. We measured the platelet count, white blood cell count, plasma fibrinogen concentration, thrombin–antithrombin III complex, plasmin-Α2 plasmin inhibitor complex, D-dimer, interleukin-6, polymorphic neutrophil-elastase, and the plasma free hemoglobin. Blood samples were collected before the start of perfusion, 15 and 60 min after the start of perfusion, 60 min after the administration of protamine, and 1 day after the operation. During the perfusion, coagulation, fibrinolysis, and inflammatory responses were activated; however, no significant differences between the two groups were noted. In this clinical investigation with suction and the cell saving system, the closed circuit was not found to be superior to the open circuit with regard to biocompatibility.

Thymic epithelial cells expressed unusual follicular dendritic cell markers: Thymic extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue

Described herein is a case of thymic extranodal marginal zone B‐cell lymphoma of mucosa‐associated lymphoid tissue. Using immunohistochemical double staining it was found that most of the thymic lymphoid follicles in this case possessed cytokeratin‐positive and follicular dendritic cell (FDC) marker‐positive cells. Moreover, using immunoelectron microscopy it was confirmed that some of the double‐positive cells were thymic epithelial cells. The candidate of cytokeratin subtype expressed on the double‐positive cells was cytokeratin 1 (CK1), which was expressed only by the epithelium of Hassalls corpuscles in thymuses from age‐matched patients with myasthenia gravis. The present case indicates a possibility that some thymic epithelial cells become FDC, although it was uncertain whether they were derived from the epithelia of Hassalls corpuscles or whether they were at the same differentiation stage as Hassalls corpuscles.

Technical considerations using a composite graft for aortic root replacement.

We performed modified aortic root replacement using a composite graft in seven patients over a 7-year-period. Six patients underwent emergency surgery for acute aortic dissection and one patient underwent elective surgery for an aortic aneurysm. To make the composite graft, we chose an artificial valve that was 1 mm larger than the graft, and when performing the proximal anastomosis, we sutured only the graft edge using the horizontal mattress suture technique, applying an additional running suture for reinforcement. The button technique was routinely used for coronary reattachment. To assess hemostasis of the aortic proximal and coronary suture line, cardioplegia was injected via the left atrial vent, which enabled us to confirm hemostasis before performing the distal anastomosis. Blood loss and the need for blood transfusion were minimized by this modified technique. None of the six survivors has required reoperation during 7-year period. Our technique of aortic root replacement based on a composite graft with some operative modifications seems to be safe and reliable, resulting in a satisfactory outcome.

A case of granulocyte colony-stimulating factor and interleukin 6 receptor-producing mediastinal mature cystic teratoma with somatic-type malignancy.

Mediastinal germ cell tumor with somatic‐type malignancy is a rare neoplasm. We describe one such case in a 49‐year‐old Japanese man who had shown an elevated serum concentration of granulocyte colony‐stimulating factor (GCSF) and leukocytosis without a shift to the left. Histologically, the tumor formed a teratomatous cyst whose wall contained benign epithelial components, well‐differentiated tubular and mucinous adenocarcinoma, and poorly‐differentiated pleomorphic carcinoma. Immunohistochemically, both the well differentiated adenocarcinoma and poorly differentiated pleomorphic carcinoma expressed GCSF. Immunohistochemistry and molecular analysis revealed that both components also produced interleukin 6 receptor (IL6R). We diagnosed this tumor as a GCSF‐ and IL6R‐producing mediastinal mature cystic teratoma with somatic‐type malignancy. The tumor showed immunohistochemical expression of activated signal transducer and activator of transcription 3. The patient died 6 months after developing systemic symptoms. For a GCSF‐producing tumor, complete resection appears to offer the best outcome at present. For any patient presenting with leukocytosis without a shift to the left, a thorough analysis should be conducted, and the tumor diagnosed as early as possible.