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Objectives: The role of bypass to the distal arteries for patients with Buerger's disease (thromboangiitis or TAO) remains controversial because of the high incidence of graft failure. We retrospectively reviewed the results of 71 bypasses to evaluate their efficacy., Materials and Methods: We performed 71 autogenous vein bypasses in 61 patients with TAO. Of the patients, 97% were heavy smokers. The indications for surgery were claudication in 41%, and ischaemic ulcer or gangrene in 59%. Of the bypasses 85% were to the crural arteries or to the arteries below the ankle. The grafts used were 53 single saphenous veins, and 18 venovenous composite grafts., Results: There were 38 graft failures, the main causes including anastomosis to a diseased artery, disease progression (which occurred in smokers after surgery), and vein graft stenosis. Of 38, 10 were restored to patency by revision surgery. Primary and secondary patency rates were 48.8% and 62.5% at 5 years, and 43.0% and 56.3% at 10 years, respectively. The patency rates of the postoperative non-smoking group was significantly higher than that of the smoking group (66.8% vs. 34.7%, p < 0.05). Thirty-six patients (59%) had successful revascularisation and returned to full-time work. However, of 28 with secondary failure, 11 underwent amputation, while 14 had persistent disabling claudication., Conclusion: Bypass to the distal arteries is an effective treatment for TAO patients, and the long-term patency is quite satisfactory as long as patients stop smoking.

A 56-yr-old housewife with cerebral astrocytoma was reported with positron emission tomography findigns using 11C-methyl-L-methionine (11C-Met) and 18F-fluorophenylalanine (18F-Phe) tracers. 11C-Met and 18F-Phe accumulated intensely in tumor lesions, although CT scans showed only a foggy low-density area. Five years and one month after, an enhancing mass appeared on CT scans. Thus, amino acid tracers may play a important role in the early diagnosis of gliomas.

To accurately differentiate nontumor central nervous system (CNS) diseases from brain tumors, we retrospectively evaluated the cerebral circulation and metabolism in patients with nontumor CNS diseases using positron emission tomography (PET). Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), oxygen extraction fraction (rOEF), the metabolic rates of oxygen (rCMRO2), and of glucose (rCMRGI), and the uptake of 11C-methyl-L-methionine (11C-Met) were visually evaluated in lesions and compared with values for the contralateral white matter regions. PET findings were correlated with those of x-ray computed tomography (CT) and magnetic resonance imaging (MRI), and were analyzed for nontumor CNS diseases and cerebral gliomas. rCBF and rCBV were changeable from disease to disease or from stage to stage of disease progression. rOEF and rCMRO2 remained low in 5 and 6, respectively, of 9 nontumor CNS diseases examined, whereas these parameters were increased in CNS infections such as brain abscess. Overall, noteworthy was the locally increased rOEF and rCMRO2 in the patients with a brain abscess in contrast to the values for patients with gliomas. rCMRGI reflected biological characteristics of each disease, and correlated with cell density, whether reactive glial cells or inflammatory cells. 11C-Met was accumulated at a certain stage of nontumor CNS diseases, which implied uptake of the tracer as a result of disruption of the blood-brain barrier as well as metabolic incorporation.

Twenty children with primary mediastinal tumor underwent surgical treatment. Ten patients had benign tumor and the other patients were malignant. Seven of ten patients with malignant tumor were neurogenic, and 3 patients were of germ cell tumor. In the clinical manifestation, 11 patients were asymptomatic. All of benign tumors were resected completely, but in a few patients with malignant tumors, the complete resection not possible. However, except for one patient with immature teratoma, all patients with malignant tumor have been surviving following postoperative chemotherapy and radiotherapy. Two infants with bronchogenic cyst were operated on their respiratory distress syndrome in emergency, and have been salvaged.

cis-diamminedichloroplatinum (II) (CDDP) has been used both alone and in combination with other chemotherapeutics for cancer chemotherapy. Although CDDP acts primarily on DNA, it can also act at the tumor-cell membrane to inhibit methionine transport. The latter mechanism of CDDP is reported to have an important role as a chemical modulator in enhancing chemotherapeutic effects of 5-fluorouracil in tumor cells. We report here the effects of CDDP on methionine uptake in an in vivo brain-tumor model. C6 brain-tumor cells were stereotactically inoculated in the right basal ganglia of 6-week-old male Sprague-Dawley rats. Ten days after the inoculation, autoradiographic images were obtained using (14C-methyl)-L-methionine. The tracer uptake, represented as differential absorption ratio (DAR) and an acid-insoluble fraction (AIF), was measured in both brain tumors and normal brain with or without an intravenous injection of CDDP. The tumor/non-tumor DAR and AIF decreased significantly (P < 0.01, as determined by the Mann-Whitney U-test) after CDDP treatment, whereas the non-tumor DAR and AIF remained almost unchanged. These findings indicate that CDDP inhibits methionine uptake selectively in brain-tumor tissue and may therefore be a potent chemical modulator in the chemotherapy of brain tumors.

To elucidate the mechanism of large neutral amino acid (LNAA) transport in cerebral gliomas and to evaluate the clinical usefulness of positron emission tomography (PET) with fluorine-18 fluorophenylalanine (18F-Phe), we examined 18 patients with cerebral glioma using dynamic PET and 18F-Phe. By employing two-compartment model analysis, the influx rate K1, the efflux rate k2 and the distribution volume (Vd) of 18F-Phe were estimated in tumour tissue and contralateral normal grey matter. 18F-Phe showed increased accumulation in tumour tissue regardless of the grade of malignancy in all patients. The rate of uptake of 18F-Phe in high-grade glioma was significantly higher than in low-grade glioma (P <0.05). However, it was difficult to evaluate the tumour grade only from the 18F-Phe accumulation in individual cases. Values of K1 and Vd were significantly increased in the tumour tissue. The K1 value of the tumour tissue tended to decrease with increasing LNAA concentration in plasma. Therefore, influx of 18F-Phe into tumour tissue is mainly related to the carrier-mediated active transport. It is concluded that PET with 18F-Phe is of clinical value for tumour detection rather than assessment of tumour malignancy.

In this paper the current technical trend for femoro-popliteal bypasses (FP) was discussed. There is a broad consensus that vascular prostheses such as Dacron or ePTFE are reliable alternatives to autogenous vein grafts (AVG) for FP above the knee (FPAK). However, AVG is employed for FP below the knee (FPBK), while there is no significant difference in long term patency between reversed vein and in situ vein grafts. Use of heparinized autogenous blood for preparation of AVG is superior to heparinized saline solution in the reendothelialization. The value for %-area of endothelial cell coverage in the AVGs is 20% at 2 hours after implantation, whereas 80% of the area is covered after one week. FPs for diabetic patients with intermittent claudication should be limited because there is a possibility of occurrence of isolated popliteal segment due to disease progression. 5-year primary cumulative patency rates of prostheses for FPAK and AVGs for FPBK are about 70%, justifying the strategy of using vascular prostheses for FPAKs.

The aim of this study was to evaluate efficacy of high dose chemotherapy and restoration of hamatopoiesis following peripheral blood stem cell transplantation (PBSCT). Three patients with pediatric malignant brain tumors (two medulloblastomas and one medullomyoblastoma) underwent high dose chemotherapy including CBDCA, VP-16, and MCNU with PBSCT. Postcontrast-MR images revealed no abnormal enhancing lesions after high dose chemotherapy in all patients. One patient with medulloblastoma has remained complete remission one year and seven months after the termination of treatment. Another patient with medullomyoblastoma died of respiratory distress syndrome one month after the second course of high dose chemotherapy. The other patient with medulloblastoma, which received PBSCT and high dose chemotherapy at the time of tumor recurrence after failure of initial treatment, suffered from multiple disseminated lesions five months after the treatment. PBSCT contributed prompt recovery from hematopoietic dysfunction in all patients. These results indicate that PBSCT may play an important adjuvant to chemotherapy and further offer a safer and more effective high dose chemotherapy in pediatric malignant brain tumor patients.

Between 1980 and 1995, 10 patients underwent thoracotomy for pulmonary aspergillosis. In six patients, hemoptysis and bloody sputum were the chief complaints. The other complaints were nonspecific. Six patients had a history of pulmonary tuberculosis, and two of those patients underwent upper lobectomy. Aspergillosis had developed in the residual space. A fungus ball was observed on the preoperative chest X-ray and CT scan films in seven patients. Lobectomy was done in three patients, segmentectomy in two, and partial pulmonary resection in four. The patients with lesions that had grown in the residual space underwent curettage with muscle plombage. Three patients underwent thoracoplasty. An additional operation was done in two patients because of poor residual lung expansion. No patient had recurrence. We conclude that surgical treatment should be based on symptoms and on pathological findings.

Traumatic diaphragmatic hernia requires urgent surgical treatment. A 51-year-old female was injured in a speeding car. She had dyspnea, and resistance on the abdominal wall on physical examination. Intra-thoracic and abdominal visceral injury was suspected. A chest roentogenogram and CT scan revealed an obvious diaphragmatic herniation on the left which necessitated emergency operation. On the right semi-lateral position, left thoracoabdominal spiral incision was made through the 7th intercostal space. Good exposure of the chest and abdomen was easily obtained. Herniated organs and the abdominal cavity were thoroughly examined with ease. The diaphragm was repaired directly. She had an uneventful postoperative recovery, and was discharged in 17 days. Thoracoabdominal spiral incision offered an excellent operative exposure for the patient with a possible combined thoracic and abdominal visceral injury.

Non-invasive positron emission tomography (PET) was performed to identify changes in blood flow and metabolism, specific to early stages of tumour occurrence or recurrence. 2 patients with slowly progressive gliomas from early to late stages of tumour development were analysed by serial PET measurements of circulation and metabolism using 15O-gas and 18F-fluorodeoxyglucose. PET revealed a persistent depression of oxygen metabolism, as indicated by the regional oxygen extraction fraction or metabolic rate of oxygen, in the regions where tumours were later found. Abnormal blood flow and metabolism may precede the morphological changes detected by computed tomography (CT) in patients with gliomas.

11C-methyl-L-methionine (C-11 Met)PET, CT and MR imaging were performed in eleven patients with malignant brain tumors before and after RT to evaluate the usefulness of positron emission tomography (PET) in monitoring tumor response to radiotherapy (RT). The subjects included five cases of intracranial malignant lymphoma (ICML) and six cases of glioma. C-11 Met uptake by the tumor (T) and the contralateral gray matter (NT) was calculated on the PET images. The mean T/NT ratio of the ICMLs and gliomas changed from 2.33 and 1.87, respectively, before RT to 1.31 and 1.58, respectively, after RT.No significant difference was found between the T/NT ratios before and after RT in either the ICMLs or the gliomas (t-test). We tentatively defined the minimum T/NT ratio, 1.2, as the threshold between tumor and nontumor regions. Tumors with a ratio of 1.2 or more were imaged as "hot" (MET) and coincided with CT or MR image lesions which were visualized as contrast-enhancing (CE) and low-density (LD) or high-intensity (HI). The relationships between PET, CT and MRI lesions were classified as follows: Type I (MET < or = CE), Type II [CE < MET < LD (HI)], Type III [LD(HI) < or = MET]. MET lesions extending regionally ( > 1 cm) beyond the respective CT or MR image lesions were designated "MET-extension" and LD (HI) lesions protruding ( > 1 cm) beyond the MET lesions were recorded as "LD (HI)-extension" on the integrated images. The type II pattern of the MET areas in all five cases of ICML before RT had changed to Type I in one case, Type III in one case and Type II in three cases, after RT, while the two Type II patterns and four Type III patterns of the gliomas had converted to four Type II and two Type III patterns. These findings indicate that gliomas tend to invade into areas of peritumoral edema more than ICMLs. There were two ICML MET-extension sites in the cortex before RT, as opposed to two in the cortex, one in the basal ganglia, one in the thalamus, and one in the corpus callosum among the gliomas. On follow-up CT or MR images MET-extension (75%) had converted to a CE or LD (HI) region. Four ICML LD (HI)-extension sites before RT were found in periventricular white matter, versus one in the cortex and three in the white matter among the gliomas. LD (HI)-extension appeared to represent vascular edema because it decreased or diminished after completion of therapy. Sequential analysis of integrated C-11 Met PET, CT and MR images is useful in detecting the extent of tumor infiltration by ICMLs and gliomas, particularly at an early stage, and for evaluating the effect of RT in the treatment of both.

We studied 50 patients with mild to moderate renal dysfunction to compare pharmacokinetics of 99mTc-MAG3 with that of 131I-OIH. After simultaneous bolus injection of both 99mTc-MAG3 and 131I-OIH, 8-point venous blood sampling was performed from 2 to 44 min post injection. Aliquoted plasma samples were counted for radioactivity along with the injected standard to obtain % injected dose/ml plasma for each tracer. Using obtained time-concentration data, classical 2 compartment model analysis was performed for both tracers to obtain various pharmacokinetic parameters, including distribution volumes (Vds), inter-compartmental rate constants, and plasma clearance. In these parameters, Vd of central compartment, Vd at steady state, central to peripheral inter-compartmental rate constant, and plasma clearance were significantly larger for 131I-OIH. In all parameters, significant correlation was found between 99mTc-MAG3 and 131I-OIH. The best correlation was seen in plasma clearance (r = 0.891, p < 0.0001). Plasma clearance ratio (99mTc-MAG3/131I-OIH), however, showed weak but significant negative correlation with serum creatinine, although this correlation was not likely to affect the overall correlation of clearance between 131I-OIH and 99mTc-MAG3. From these results, we confirmed that 99mTc-MAG3 clearance could be used as an alternative to 131I-OIH clearance, although pharmacokinetic behavior of 99mTc-MAG3 was not exactly the same as that of 131I-OIH.

We examined regional cerebral blood flow response in a patient with gray matter heterotopia located beneath the sensorimotor cortex during a finger tapping task. We found regional cerebral blood flow was specifically increased during contralateral finger tapping. This indicated the possibility of functional differentiation of the ectopic neurons despite incomplete migration.

A case of frontal hypertrophic cranial pachymeningitis was presented with positron emission tomography (PET) using (11C-methyl)-L-methionine (11C-Met). A 55-year-old male developed right hemiparesis after generalized tonic convulsion one month prior to admission. MR images revealed patchy enhancement extending from the dura mater to the cerebral parenchyma surrounding high T2-weighted signal in the left frontal region. Left carotid angiogram showed atresia of the rostral superior sagittal sinus and obliteration of the cortical veins associated with compensatory venous channels coursing in the frontal deep white matter. PET demonstrated high 11C-Met uptake in the area corresponding to the enhancing lesion on the MR images. The ratio of lesion/normal cortex was 1.58 as an indicator of selective uptake in the lesion. The contralateral temporal gray matter was representative of a normal cortex. In contrast, 11C-Met did not accumulate in the frontal white matter where T2-weighted MR images showed abnormal high intensity lesion. This suggested that the frontal white matter lesion was derived from vasogenic edema due to venous infarction. The patient underwent an uneventful exploratory biopsy. The dura mater had proliferated to a thickness of 3.5mm and was tightly adherent to the left middle frontal gyrus. Microscopically, the thickened dura mater where the tracers had accumulated was composed of abundant collagenous fibers together with diffuse infiltration of inflammatory cells, including predominantly lymphocytes, plasma cells, and neutrocytes. The lymphocytes, which proved positive in both UCHL-1 and L26 staining, had no atypism. Histological findings corresponded to hypertrophic pachymeningitis. Met-PET clearly represented viable and infiltrative zones of inflammatory cells. The patient's neurological symptoms and signs gradually improved. Follow-up MR images three months after the surgery showed the enhancing lesion to be diminished and a marked regression of the vasogenic edema. Spatial determination of viable lesions permitting differentiation from biological inactive or vasogenic edema is an important guideline in selecting an appropriate surgical procedure in the diagnosis and treatment of hypertrophic cranial pachymeningitis. Met-PET would appear useful in delineating inflammatory lesions such as hypertrophic cranial pachymeningitis.

Objectives: To clarify the course of re-endothelialisation (Re-E) in an entire graft and to establish the effect of immersion media for the preservation of endothelial cells., Methods: Autogenous femoral veins of dogs were immersed in heparinised saline solution (n = 18) or heparinized autogenous blood (n = 18). After immersion, the grafts were implanted into bilateral femoral artery, and were retrieved 1 day to 4-8 weeks after implantation., Results: For the grafts immersed in the heparinised saline solution, the values for % area of endothelial cell coverage before implantation, and at 1 day, 1 week, and 4 weeks after implantation were 44.9%, 6.2%, 14.5%, and 81.3%, respectively. For the grafts immersed in heparinised autogenous blood, the values were 73.5%, 20.6%, 79.2% and 95.5%, respectively. However, such relatively rapid speed of Re-E slowed down considerably after 1 week following implantation in this group., Conclusions: The use of heparinized autogenous blood is strongly recommended as a preparation media for autogenous vein grafts. Almost all of the endothelial cells fall away in the earlier period after implantation and regenerate multifocally and irregularly. Re-E is incomplete even at 8 weeks after surgery, and we suggest that the area of incomplete Re-E may develop into intimal hyperplasia.

The efficacy of a reinforced biosynthetic ovine collagen (RBOC) vascular prosthesis developed for small arterial reconstruction was assessed by examining 30 grafts in 29 patients with arteriosclerosis obliterans. The operative procedures performed were femorofemoral bypass in 2 patients, above-knee femoropopliteal bypass in 28 patients, and below-knee femoropopliteal bypass in 1 patient. Femoropopliteal bypass was simultaneously performed in two patients undergoing femorofemoral bypass using one or two grafts. The indications for surgery were intermittent claudication in 27 patients and to salvage the limb in 2 patients. The longest follow-up period was 49 months, and there were six graft failures, occurring 1, 1, 9, 17, 17, and 23 months after implantation, respectively; caused by compression of the graft from outside in two, infection in one, anastomotic intimal hyperplasia in one, and unknown factors in two. Thus, the primary cumulative patency rate for above-knee femoropopliteal bypass at 3 years was 83.7%, and the secondary patency rate was 91.2%. No aneurysmal change was observed. Moreover, the RBOC was able to be used without preclotting, and its handling and suturing characteristics were satisfactory. Our findings suggest that this vascular prosthesis may be an acceptable alternative for above-knee femoropopliteal bypass.

An intramedullary spinal cord ependymoma was studied by positron emission tomography (PET) using (11C-methyl)-L-methionine (11C-Met). MRI showed a homogeneously enhancing tumour at C6-T2 with cysts at its rostral and caudal ends. Sagittal PET images demonstrated high 11C-Met uptake in the solid portion of the tumour, particularly ventrally at C7-T2, where viable tumour cells proliferated in association with abundant perforating vessels. Met-PET would appear useful for delineating the viable portion of intramedullary ependymomas.

Four patients underwent resection of mediastinal malignant tumors with invasion to the superior vena cava. Two patients had invasive thymoma, one seminoma, and one metastatic mediastinal lymph nodes of unknown origin. Prior to resection of the tumor, an ePTFE graft was anastomosed between the innominate vein and the right atrium to maintain the venous drainage from the brain and the upper extremities. In two patients, the superior vena cava was reconstructed by patch angioplasty after the tumor with a part of the vena cava was safely resected. One patient died of acute respiratory failure, but the other three are alive and well without any evidence of graft obstruction. This safe and useful method in order to prevent cerebral congestion during and after resection of the tumor.

Background: New World Health Organization classifications have categorized central neurocytomas as neuronal tumors. The differential diagnosis between central neurocytomas and other tumors is important for selection of the optimal therapy modality for the management of intraventricular tumors. To characterize the pathophysiology and proliferating activity of central neurocytoma accurately, cerebral blood flow and metabolism in five patients with central neurocytoma were studied using positron emission tomography (PET)., Methods: Tracers used for the present study included C15O2, C15O, 15O2, and 18F-fluorodeoxyglucose (FDG). Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), oxygen extraction fraction (rOEF), cerebral metabolic rate of oxygen (rCMRO2), and cerebral metabolic rate of glucose (rCMRGl) were quantitatively analyzed in tumor lesions and the contralateral gray matter. Four patients with central neurocytoma underwent a complete PET study, including all circulatory and metabolic parameters; one patient was studied with 11C-methyl-L-methionine and FDG tracers., Results: Tumor rCBF and rCBV were higher than comparable values in the contralateral gray matter in three of four patients. This high level of perfusion corresponds to angiographic findings that show intense tumor staining in tumors fed by perforated arteries. Tumor rOEF and rCMRO2 were significantly lower than corresponding values in the gray matter (rOEF, P < 0.01; rCMRO2, P < 0.05 by Student's t test). Tumor rCMRGl ranged from 2.68 to 6.26 mg/100 ml/minutes and did not exceed contralateral gray matter values in any of the five patients. Tumor rCMRGl was significantly lower (P < 0.02) than the gray matter rCMRGl. One tumor exhibited a relatively high value of rCMRGl (comparable to gray matter rCMRGl), and increased in size 4 months after partial resection. No other tumors appeared during postoperative follow-up periods that ranged from 4 to 135 months., Conclusions: Circulation and metabolism parameters measured by PET offer insight into the biologic characteristics of central neurocytoma. Tumor rCMRGl may be an indicator of the proliferating activity in central neurocytoma.

To estimate proliferating activity of central neurocytoma, we measured kinetic rate constants and glucose metabolic rate (kinetic-rCMRGI) using dynamic positron emission tomography (PET), as well as autoradiographic rCMRG1 (arg-rCMRG1), in patients with histologically verified central neurocytoma. The subject included five patients, four males and one female, aged from 23 to 53 years with a mean age of 41 years old. All tumors were located in the lateral ventricle and two extended into the third ventricle through the forearm of Monro. Tumor lesion on the PET images was determined using CT or MRI, which was performed at levels equivalent to those for the PET scans. The kinetic rate constants of tracer transport from blood to brain (k1), reverse transport from brain to blood (k2), and phosphorylation (k3) were analyzed according to the three compartment 18F-fluorodeoxyglucose (FDG) model. For quantitative analysis, regions of interest (ROI) on PET images were delineated on the tumor and the contralateral gray matter. Tumor k1 and k2 values were similar to or higher than those of the contralateral gray matter, suggesting high permeability due to lack of blood-brain barrier. Tumor k3 value, an indicator of hexokinase activity, and kinetic-rCMRG1 were exceedingly lower in three of five patients. These three patients have been free from tumor recurrence or regrowth, postoperatively. The other two patients, tumor kinetic-rCMRG1 was similar to or higher than that of the contralateral gray matter. One patient suffered from tumor regrowth shortly after resection, and the other has been followed up postoperatively. Thus, k3 and kinetic-rCMRG1 are indicative parameters of proliferative activity in central neurocytoma.

We investigated the biological response and biodegradation of CL301, a presealed woven Dacron prosthesis (UBE woven) with glutaraldehyde stabilized gelatin. The sealant does not affect its handling characteristics because of the glycerin treatment. The total content of endotoxin in the CL301 was 5.3 +/- 0.5 pg/mg of sealant material (1.7 +/- 0.2 pg/cm2), which was 1/5 and 1/6 of that found in Hemashield and Gelseal, respectively. The pyrogen test was negative and the content was estimated below the minimum pyrogenic doses for thoracic aortic surgery. Five cm-long grafts with a diameter of 10 mm were implanted into the descending thoracic aorta of dogs weighing 10-16 kg. These grafts were retrieved 2 hours, 7, 10 days, 5, 8 and 10 weeks after implantation. Thrombus-free surfaces were 28%, 77%, at 5 and 10 weeks and there was no excessive inflammatory response to the sealant. The total, and the effective sealant remaining were 80.6%, 56.5% at 5 weeks, 60.8%, 38.3% at 10 weeks, respectively. The sealant was removed more rapidly from the inner surface than from the outer. In half of the graft area, the sealant was removed or detached from the Dacron surface 5 weeks after implantation, indicating that delayed resorption of the sealant substantially did not affect the healing process. We conclude that because of the harmless amount of endotoxin and effective sealing for 5 weeks, followed by an acceptable healing process experimentally, CL301 is the presealed Dacron graft of choice for thoracic aortic surgery.

A 74-year-old man developed sudden cardiogenic shock 5 days after the onset of acute myocardial infarction. Echocardiographic diagnosis was severe mitral regurgitation due to papillary muscle rupture. Despite the effort to support the hemodynamics with catecholamines and IABP, the patient's condition deteriorated rapidly, which necessitated emergency operation. Anterolateral papillary muscle was found to be totally ruptured. Coronary artery revascularization and mitral valve replacement were performed. Postoperative course was uneventful, with two days of IABP and three days of ventilatory support. The patient could start rehabilitation program on the 7th postoperative day. He was discharged in 2 months in NYHA class I. Reports of successful emergency operation for total papillary muscle rupture following acute myocardial infarction are rare. Involvement of anterolateral papillary muscle is rarer. Early diagnosis and surgical treatment are mandatory to save this group of patients.

We measured kinetic rate constants and glucose metabolic rate (kinetic-rCMRGl) using dynamic positron emission tomography (PET), as well as regional cerebral blood flow (rCBF), blood volume (rCBV), oxygen extraction fraction (rOEF), oxygen metabolic rate (rCMRO2) and autoradiographic rCMRGl (arg-rCMRGl), in patients with meningioma. Ten patients including one recurrent case, two males and eight females aged from 44 to 71 years with a mean age of 54 years old, were studied prior to surgical interventions. Histological diagnosis was as follows: seven cases of meningothelial type, two cases of angiomatous type and one fibrous type. For quantitative analysis, regions of interest (ROI) on PET images were delineated on the tumor and the contralateral gray matter in comparison with eight cases with malignant gliomas (five cases of malignant astrocytoma and three cases of glioblastoma, aged from 14 to 70 years with a mean age of 41 years old). Hemocirculation of the tumor was exceedingly higher than that of the contralateral gray matter, which corresponded to neuroradiological findings of abundant tumor vessels. Low rOEF implicated an excessive blood flow beyond oxygen demand of the tumor. The raised metabolic rate (rCMRO2/rCMRGl) suggested rather aerobic glycolysis as compared with malignant gliomas. The kinetic rate constants of tracer transport from blood to brain (k1), reverse transport from brain to blood (k2), and phosphorylation (k3) were analyzed according to the three compartment model of 18F-fluorodeoxyglucose (FDG). Tumor k1 and k2 values markedly increased in all examined cases, suggesting high permeability due to lack of blood-brain barrier and an abundant blood supply.(ABSTRACT TRUNCATED AT 250 WORDS)

Tuberous sclerosis (TS) is well known to be occasionally associated with subependymal giant cell astrocytoma (SGCA). SGCA is considered to be a benign tumor in its clinical course and morphology. However, this tumor is grown sometimes so rapid and caused hydrocephalus. To our knowledge, little is known about hemocirculation and metabolism, particularly in relation with proliferating activity of TS and SGCA. We measured hemocirculation and metabolism of SGCA developed in a case of TS using positron emission tomography (PET). A 13-year-old-boy who had frequently developed convulsions four months after birth. He was diagnosed as TS and had been medically treated with anticonvulsants, since multiple intraventricular calcifications were detected by CT, at the age of five months. The convulsions had been well controlled. In March 1993, he presented with syncopal attack and admitted to our hospital. CT showed multiple subependymal nodules. Among the nodules, one of the left anterior horn exceeded 2cm in size obliterated Monro's foramen. The tumor was homogeneously enhanced with contrast medium. The lesion detected by postcontrast T1-weighted MR imaging had almost the same status as that by CT. T2-weighted image revealed cortical tubers as high intensity area at the left frontal and parietooccipital regions. PET was performed with the Headtome IV. Hemocirculation of the tumor was lower than that of contralateral gray matter, which suggested poor blood supply. The oxygen and glucose metabolism of the tumor were decreased compared with contralateral gray matter, indicative of a low activity of proliferation and a clinically benign tumor in the present case.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral hemocirculation and glucose metabolism in a malignant astrocytoma were repeatedly quantified before and after intracarotid injection of recombinant human tumor necrosis factor-alpha (rH-TNF) using positron emission tomography (PET). The patient received an intracarotid injection of a 3 x 10(4) U/m2 dose of rH-TNF three times over a two week period. PET was performed prior to and 24 hr after the first injection, and two weeks after the third injection. Prior to the first rH-TNF treatment, two lesions demonstrating high perfusion and hypermetabolism of glucose were noted in the right frontal and temporal regions. The frontal hypermetabolic lesion showed decreases in hemocirculation and metabolism 24 hr after the first injection and then increases beyond the pre-treatment level two weeks after the third treatment, whereas the temporal lesion remained unchanged during the follow-up period. No appreciable changes were noted in the adjacent cortex where rH-TNF was perfused, with the exception of a transient decrease in regional blood volume. Magnetic resonance images of the tumor showed no changes as a result of treatment with intracarotid rH-TNF. Intracarotid rH-TNF preferentially affects tumor tissue as opposed to normal cortex.

We repeatedly measured kinetic rate constants and glucose metabolic rate (kinetic rCMRG1) using dynamic positron emission tomography (PET) and autoradiographic rCMRG1 in a patient with recurrent meningioma. A 50-year-old woman who presented with a left visual disturbance was admitted to our hospital. MR images revealed a mass lesion occupying the left middle fossa. The patient underwent Simpson grade IV surgery. The histological diagnosis was meningothelial meningioma. One year later the tumor had grown back to almost the same size as before treatment and was removed again by Simpson grade IV procedure. Postoperatively, the patient underwent radiation therapy (54 Gy). Two years after the second operation, the tumor was found to have invaded the left orbit and was resected by Simpson grade IV procedure. After additional radiation therapy, the patient was discharged. The rate constants were analyzed preoperatively and whenever the tumor recurred according to the three compartment 18F-fluorodeoxyglucose (FDG) model. Preoperative PET indicated tumor k1 and k2 values higher than in the contralateral gray matter, suggesting high permeability due to absence of the blood-tumor barrier and an abundant blood supply. The tumor k3 value, an indicator of hexokinase activity, was as high as in the contralateral gray matter. When the tumor recurred, the tumor k1, k2 and k3 values remained consistently high, indicating high proliferative activity. In contrast, the contralateral gray matter k1, k2 and k3 values decreased to some extent, suggesting effects of surgery or radiotherapy. Tumor rCMRG1 values, both autoradiographic and kinetic, were enhanced markedly.(ABSTRACT TRUNCATED AT 250 WORDS)

We report a very rare case of an infant with coronary arterial fistula in whom the communication between a dilated right coronary artery and the coronary sinus was found. The patient was 1-year-old. She had pulmonary congestion and cardiomegaly due to the left-to-right shunt through the fistula, and underwent ligations of the fistula. Ligations of the fistula was indicated because the patient was too small to undergo a fistula resection and coronary arterial bypass grafting. Although the patient had a successful post-operative course, we are paying attention to the aneurysmal change of the dilated right coronary artery proximal to the site of ligations.

Brachiocephalic aneurysms are relatively rare in Japan. A case with tandem aneurysms of innominate and right carotid artery was experienced and its successful surgical treatment was reported. A 54-year-old female patient had an attack of cerebral infarction with left hemiparesis. Computed tomography and angiogram revealed aneurysms of innominate and right carotid artery causing cerebral embolisms. Aneurysmectomy and replacement with Dacron prosthesis was performed. A temporary shunt was utilized between ascending aorta and common carotid artery during clamping carotid artery. She had no problems after operation, and her postoperative course was uneventful.

Background: Noninvasive measurements of cerebral circulation and metabolism may be useful for diagnosis in patients with brain tumors. The authors tested the prognostic significance of circulatory and metabolic values or ratios determined by positron emission tomography (PET) in patients with gliomas., Methods: The subjects were 23 patients, who underwent a complete PET study of cerebral circulation and metabolism with long-term follow-up of at least 57 months. Regional cerebral blood flow (rCBF), blood volume (rCBV), oxygen extraction fraction, and the metabolic rates of oxygen (rCMRO2) and glucose (rCMRGl) were measured before treatment. Data regarding tumors, the contralateral gray matter and white matter, and the ratio between tumor and gray matter or between tumor and white matter were compared with survival time from the time of the PET study. Prognostic factors were tested using Cox's regression analysis., Results: Among clinical parameters, histologic grade and performance status were important variables regulating survival. When survival times of patients with values or ratios equal to or higher than the median were compared to those of patients with values or ratios lower than the median, significant determinant PET measurements were tumor rCMRGl and the ratios of tumor:gray rCMRGl and tumor:white rCMRGl. Median survival time in the patients with an rCMRGl value of 4.4 mg/100ml/minute (median value) or more indicated 9 months, which was significantly shorter than greater than 113 months in the patients with a value lower than the median (P = 0.003 by the generalized Wilcoxon test). Patients with a higher value of gray rCBF, rCBV, or rCMRO2 had significantly longer survival times than those with a lower value., Conclusions: Cerebral circulation and metabolism as determined by PET can be of ancillary significance in predicting the prognosis of patients with gliomas.

The peripheral type of Buerger's disease is unresponsive to conservative therapy when accompanied by multisegmental occlusion at the level of the ankle. Between November 1983 and April 1993, we performed 15 bypasses below the ankle for this type of thromboangiitis obliterans in 13 patients (mean age 45.7 years), including four females. Ten patients had intractable toe ulcers with severe pain, and five had foot-threatening ischemia or disabling foot claudication. Eleven patients were heavy smokers, two were passive smokers, and six had a history of sympathectomy. All patients had occlusion of the three main crural arteries or both of the tibial arteries at the ankle. Of the 15 bypasses, 10 were to the medial or lateral plantar arteries, two were to the common plantar artery, and three were to the dorsalis pedis artery. There were three early and three late graft failures. The causes of early graft failure were thrombosis at the site of cross-clamping, anastomosis to a diseased segment, and arterial spasm. The three late failures (> 3 months) were due to disease progression in patients who continued to smoke, whereas all grafts remained patent and functioned well in patients who stopped smoking. Because patients with thromboangiitis obliterans are relatively young and active, early healing of ulcers and restoration of normal limb function are important objectives in their treatment. Bypass to the foot arteries can provide an excellent outcome, although special techniques and postoperative cessation of smoking are essential for success.

Recent advances in the field of peripheral arterial reconstruction have been remarkable. These advances are mainly derived from the development of diagnostic technology such as Doppler ultrasound analysis, further refinement of surgical technique including surgical instruments and materials, and naturally improvement of patient care in the pre-, peri- and postoperative period. During the past 14 years we have performed peripheral arterial reconstruction in 1,200 cases (1,660 limbs) mainly with occlusive lesion due to arteriosclerosis obliterans. In our hand, aorto-iliac occlusive lesion has been routinely bypassed with Dacron prostheses and the secondary patency rate at eleven years reached 96.5%. The main problems encountered in this region were anastomotic aneurysm in the femoral artery (3.9%) and graft infection (1.2%). In the infrainguinal region there are still problems to be solved, although the primary (secondary) 5 year patency rates of reversed vein graft as well as in situ vein graft including femoro-popliteal below knee and femoro-crural bypasses have exceeded 70% (85%). First, there is no graft material comparable to the autogenous vein (AVG). Secondly, many of the AVG should suffer occlusive pathological changes from the environment in the long term following surgery. At the present time, we have no effective method to solve these problems, therefore we should follow up the patients heedfully to maintain the graft patency as well as to improve their quality of life and prognosis.

The endocrine therapy with high-dose medroxyprogesterone acetate (MPA) was applied for 19 patients with recurrent breast cancer and 3 with advanced breast cancer. According to the dominant lesion of the disease, the patients were divided into three groups; 13 with soft tissue lesion, 5 with visceral lesion, and 4 with osseous lesion. The serum MPA level was higher than 25 ng/ml in 14 cases out of 19 examined. The results of objective responses in second-line therapy with MPA were CR in two cases, and NC or PD in 20 cases. In 19 out of 22 patients with MPA therapy, the periods of survival were longer than the period of 50% survival of the patients without MPA therapy.

A case of radiation-induced vasculopathy of a pineal glioma was presented with haemodynamic and metabolic changes before and after radiotherapy. After radiation of 60 Gy with conventional fractionation (1.8-2.0 Gy daily, 5 days per week), regional blood flow, oxygen extraction fraction, metabolic rate of oxygen, kinetic metabolic rate of glucose and the rate constants (K2, K3) were markedly depressed (20% or greater) compared with the pre-irradiated study. 7 months after radiotherapy, the patient developed transient transient episodes of both right and left upper limb convulsion, terminating in generalized convulsion. When she developed status epilepticus, computed tomography showed extensive low density areas in the territory supplied by the right middle cerebral and the right posterior cerebral arteries. Cerebral angiography revealed diffuse stenosis at both carotid bifurcations and at the origins of the right posterior communicating and posterior cerebral arteries. Haemodynamic and metabolic depression therefore implicated radiation-induced vasculopathy in the present case.

One hundred and eight bypass operations for Buerger's disease were performed between November 1976 and August 1990. The bypass procedures, prostheses, cumulative patency rate and the influence of smoking on the results were discussed. Five-year cumulative patency rate of Aorto-femoral bypass was 88.2%. Aorto-femoral bypass should be always indicated as a standard procedure for the iliac lesion in Buerger's disease, because the patency rate was very low in aorto-iliac bypass group or ilio-femoral bypass group. Five-year cumulative patency rate of infrainguinal bypass using autogenous vein was 64.8%, and that in the patients who quit cigarette smoking was as high as to 73.3%. We should use autogenous vein as much as possible for infraiguinal bypass and discontinuance of cigarette smoking is considered to be one of the important factors to improve the patency rate in Buerger's disease.

Primary central nervous system (CNS) involvement of non-Hodgkin's lymphoma is uncommon and a vast majority of reported cases are of B-cell origin. We present a 52-year-old woman with primary peripheral T-cell lymphoma of the brain. Immunostaining of paraffin-embedded sections proved tumor cells to be positive for T-cell markers MT1 and UCHL1, and negative for B-cell markers MB1, and 4KB5. Radiotherapy combined with steroid therapy rendered neurologic recovery and complete tumor remission confirmed by computed tomography and magnetic resonance imaging. From a review of documented 19 cases of primary CNS T-cell lymphoma including the present case, this disease is characterized by poor prognosis among CNS lymphomas.

Autoradiographic study of (14C-methyl)-L-methionine with brain tumor bearing rats aimed at an elucidation of the mechanism of tracer accumulation in the protein synthesis of tumor. Twice as much tracer accumulated in the tumors compared as in the contralateral gray matter (nontumor region) at 90 min post intravenous injection. The protein-bound fraction of the tumors, expressed as acid-insoluble fraction (AIF), was 1.7 +/- 0.6 (mean +/- standard deviation, n = 6), significantly higher than that (0.8 +/- 0.2) of the nontumor region (p < 0.05 by the Mann-Whitney test). The tumor AIF comprised 82.3 +/- 9.2% of the total amount of the tracers accumulated in the tumors. The protein synthesis inhibitor cycloheximide reduced the tracer uptake and the AIF of the tumors to an almost same level as the nontumor region. These findings indicate that metabolic acceleration of protein synthesis may be a main reason for the high accumulation of (14C-methyl)-L-methionine in tumor.

A successful experience of a case with chronic traumatic thoracic aneurysm is reported. A 51-year-old male patient had a history of a blunt chest trauma in a traffic accident one and a half year ago. He developed gradual hoarseness because of the recurrence nerve paralysis. Computed tomography and angiography revealed a saccular aneurysm at thoracic descending aorta. It was treated with direct closure of the tear under partial clamp of the aorta. His postoperative course was excellent. He is doing well two years after operation.

A series of 241 consecutive autogenous vein bypasses for chronic lower-limb ischaemia performed by two surgeons since 1980 was reviewed. After 1985, in situ vein bypass was employed preferentially and was compared with reversed vein bypass. The two groups of patients had similar risk factors, indications and outflow. Of the 241 bypasses, 157 were to the below-knee popliteal artery and 84 to infrapopliteal arteries. The utilization rates of a single ipsilateral saphenous vein were 57.5% for reversed and 71.9% for in situ vein bypass. However, in situ vein bypass was impossible in 43 procedures and these were changed to the reversed operation with contralateral vein. The primary 5-year patency rates of reversed and in situ vein bypass grafts to the popliteal artery were 82.5 versus 74.5%, and the primary 4-year patency rates for infrapopliteal bypass 68.5 versus 80.0%. The respective secondary patency rates were 94.2 versus 92.1% and 85.7 versus 91.1%. The main cause of graft failure was vein graft stenosis (reversed vein bypass, 13.0%; in situ, 11.1%), which usually occurred in the first 2 years after surgery. Of 23 grafts revised for stenosis, 21 were salvaged and restenosis rarely occurred. Both reversed and in situ vein bypass grafts were equally effective, but careful surveillance for 2 years and aggressive revision were extremely important after either type of reconstruction.

To elucidate metabolic pathways of methionine in brain tumors, we studied autoradiographic images of (14C-methyl)-L-methionine (14C-Met) in transplanted rat brain tumors. 14C-Met accumulated in the tumor almost twice as much as in the gray matter 90 min after injection. The acid-insoluble fraction, which was bound to macromolecules, comprised 84% the total count of the accumulated tracers in the tumor. Analysis of 14C-Met tracer accumulation is informative for understanding amino acid metabolism in brain tumors.

Two cases of an extensive bowel infarction occurred during Intraaortic Balloon Pumping (IABP) are reported. In the first, an acute myocardial infarction was seen suddenly on the seventh postoperative day following arterial reconstruction of the right lower leg and his condition required IABP support. Five day after beginning of IABP, severe symptoms suggesting peritonitis appeared, and laparotomy revealed an extensive infarction of small bowel and sigmoid colon. In the second, the patient required IABP support for weaning from cardiopulmonary bypass after completion of coronary artery bypass grafting. A severe peritonitis was caused by an extensive infarction of small and large intestine during two days of IABP support. Cholesterol emboli were found in the small bowel arteries of the case 1 at microscopic examinations of the autopsy specimen. Both patients died of cardiopulmonary failure and renal failure respectively, though necrotic intestine were resected. Circulatory support using IABP should not be selected, when a patient has severe arteriosclerotic lesions of the aorta.

A 41-year-old male developed radiation-induced bilateral cystic frontal lobe necroses after irradiation for an olfactory neuroblastoma. Computed tomography (CT) and magnetic resonance (MR) imaging revealed the lesions, one containing a fluid-blood level on CT scans and niveau formation on MR images. It was proved to be a coagulated hematoma within the cyst at surgery. Such a fluid-blood level in a radiation-induced cyst has never been reported, although hemorrhage frequently accompanies delayed radiation necrosis. Positron emission tomography with multiple tracers may be useful in differentiating cerebral radiation necrosis from tumor recurrence, because of absence of abnormal tracer accumulation.

Two cases of histologically proven primary cerebral malignant lymphoma were examined serially with positron emission tomography (PET) using 11C-methyl-L-methionine (11C Met). Lesions delineated by 11C Met accumulation extended beyond enhancing areas on either X-ray computed tomography (CT) or magnetic resonance imaging. High uptake of 11C Met accurately showed biologically active and residual tumours, at a time when disappearance of a contrast-enhancing lesion on CT seemed to indicate involution. PET provides valuable information on the extent of tumour and assessment of radiotherapy in malignant lymphoma.

A 50-year-old farmer with plasma cell granuloma had PET scans showing marked accumulation of C-11 Met. The PET had superiority in imaging the existence and extent of the lesion and monitored therapeutic response as compared with CT and MR imaging. PET yields information on hemocirculatory and metabolic aspects of this rare disease.

A case of gliomatosis cerebri was studied with positron emission tomography (PET). Carbon-11-L-methionine (11C-Met) accumulated in the diffusely infiltrative tumorous area more widely and accurately than the lesion detected by conventional x-ray computerized tomography (CT) or magnetic resonance (MR) imaging. Autopsy findings three months after the time of the PET study showed good anatomical correspondence between the extent of densely aggregated tumor cells and the region with high uptake of 11C-Met. PET may offer an innovative approach in the delineation of gliomatosis cerebri, which has not been clearly recognized by CT or MR.

A 2-year-old girl with medulloblastoma who had postoperative radiotherapy and intrathecal administration of methotrexate is reported. Five months after radiation and chemotherapy, she developed involuntary movement. Positron emission tomography (PET) demonstrated that the metabolic rate of glucose was depressed markedly in the temporal and occipital lobes, indicative of metabolic depression induced by radiation. Prompt initiation of steroid therapy ameliorated the patient's neurological symptoms. Follow-up PET revealed an increase in 18F-fluorodeoxyglucose uptake in the entire brain, including temporal and occipital lesions. No areas with high accumulation of (11C-methyl)-L-methionine were detectable. We concluded that PET may be useful in establishing an early diagnosis of radiation injury of the brain and in monitoring metabolic changes following radiation in brain tumor patients.

Sixteen patients with gliomas (7 low grade, 9 high grade) were examined using positron emission tomography (PET) with intravenous administration of 22.2 MBq/kg (0.6 mCi/kg) of (11C-methyl)-L-methionine (C-11 Met). The tracer uptake in regions of interest was calculated on PET images taken 45 minutes after injection; the uptake index was represented as a percentage of the total count in the arterial blood summed over 45 minutes. C-11 Met uptake indices in the tumors ranged from 0.020 to 0.041% with a mean of 0.032% for the low-grade gliomas and from 0.013 to 0.044% with a mean of 0.036% for the high-grade gliomas. These indices significantly increased as compared with those in the contralateral gray matter (0.008-0.032% with a mean of 0.023%; p less than 0.01 vs. low-grade gliomas, p less than 0.001 vs. high-grade gliomas). In the low-grade gliomas, C-11 Met PET images clearly depicted the existence and even the extent of the tumors, although x-ray computed tomography (CT) did not always distinguish tumoral lesions. In the high-grade gliomas, the areas of tracer accumulation regionally extended to peritumoral low density on CT scans, where malignant tumor cell infiltration was proved by operative and follow-up CT findings. C-11 Met may be a useful radiopharmaceutical for differential diagnosis of gliomas, and the accuracy of tumor localization will give us a better rationale in therapeutic strategies for surgery and radiation therapy of gliomas.

Presented is a retrospective study of 20 patients with intracranial germ cell tumors who the authors have treated during past 10 years. The cases among these patients included thirteen germinomas, three teratomas, two embryonal carcinomas, and two malignant teratomas. A ventriculoperitoneal shunt was installed in 15 cass and the tumor was surgically removed in four cases. All cases were irradiated with 33 to 61 Gy; in 18 cases, more than half of the total dose was delivered to the whole brain, and in 9 cases, spinal irradiation was given because of a verified CSF dissemination. Chemotherapy was the regimen for four cases. The tumor responded to therapy in 16 (84%) of 19 evaluable cases. Overall, the median and five year survival were 102 months and 83%, respectively. The survival rate was found to vary between the benign group (germinoma, teratoma) and the malignant group (embryonal carcinoma, malignant teratoma, germinoma with STGC) (p less than 0.01).