Biomedical subjects

K Okadome

Publications and source records attributed to K Okadome.

At least 37 records · Page 2Linked to original sources

PubMed1994

Persistent sciatic artery: two case reports and a review of the literature.

Persistent sciatic artery (PSA) sometimes shows variant vascular symptoms such as chronic or acute limb ischaemia and a pulsatile mass in the buttocks caused by aneurysmal dilatation. This report presents two cases of surgically treated PSA that caused lower-limb ischaemia. The first patient, a 58-year-old man, showed acute limb ischaemia in the chronic clinical course, and thrombectomy and patch angioplasty were performed. The second patient, a 70-year-old woman, had an incomplete type of PSA without development of the femoral artery while complaining of a 10-year history of coldness and numbness in the left lower limb. A left common iliac to profunda femoris arterial bypass was performed. This is the second case of symptomatic incomplete PSA reported in the literature. This report also reviews 45 cases of PSA published since 1977. The diagnosis of PSA requires arteriography that includes the bilateral iliac systems. Femoropopliteal bypass and, in the case of sciatic artery aneurysm, a ligature of the sciatic artery are recommended for the surgical treatment of PSA.

Aged↗

PubMed1993

The reversibility of impaired prostacyclin production of the vein graft.

The effects of changes in shear stress (shear stress variation) on production of prostacyclin (PGI2) were examined in canine autologous vein grafts, which were implanted in the poor or normal distal runoff limbs. Four weeks after grafting, the vein grafts were perfused ex vivo and PGI2 was assayed as 6-ketoprostaglandin F1 alpha. The vein grafts were perfused under constant flow for the first 30 min and then under pulsatile flow simulating an abnormal flow with a low shear stress variation or a normal flow with a high shear stress variation for the next 30 min. Basal production rates (30-min cumulative PGI2 production) of vein grafts implanted in the poor runoff and normal runoff limbs were 1.97 +/- 0.71 and 2.19 +/- 0.40 ng/cm2, respectively, with no significant difference. Pulsatile flow effects (increased PGI2 production between 30 and 60 min) of simulated abnormal versus normal flow were 0.50 +/- 0.50 ng/cm2 versus 2.31 +/- 1.87 ng/cm2 in vein grafts implanted in poor runoff limbs (P < 0.05) and 0.48 +/- 0.41 ng/cm2 versus 3.48 +/- 1.08 ng/cm2 in vein grafts implanted in normal runoff limbs (P < 0.01), respectively. There were no significant differences in simulated normal flow effects between poor runoff limbs and normal runoff limbs. The results indicate that the release of PGI2 in vein grafts may decrease in the presence of an abnormal blood flow with a low shear stress variation. In addition, it is suggested that even vein grafts implanted in the poor runoff could increase PGI2 production once the grafts were placed into normal arterial circulation.

Animals↗

PubMed1993

Combination of preoperative lymphangiography using lipiodol and intraoperative lymphangiography using Evans Blue facilitates the accurate identification of postoperative chylous fistulas.

In a 61-year-old woman who underwent extensive retroperitoneal lymph node dissection for rectal cancer, postoperative chylous ascites developed. The site of the lymphatic leak was evident on the lymphangiogram with lipiodol taken prior to the surgical repair of the leak, and another site seen on the intraoperative lymphangiogram using Evans Blue. A direct surgical repair led to good results. Therefore, the combination of pre- and intraoperative lymphangiography facilitates the successful surgical management of rare but alarmingly dangerous postoperative chylous ascites.

Chylous Ascites↗

PubMed1993

Operative transluminal laser angioplasty as the sole treatment for late stenoses of femorodistal artery bypass graft: experimental and clinical studies.

To determine the role of Nd:YAG laser thermal angioplasty as the sole treatment for late stenoses of femorodistal artery bypass graft, the lasing effect of a larger size of hot-tip probe (3, 4, and 5 mm) was experimentally studied in vitro. For an adequate lasing effect, 30 watts of laser power output for 3 seconds was needed for the 3 mm probe, 40 watts for the 4 mm probe, and 50 watts for the 5 mm probe, respectively. Based on these results, we used Nd:YAG laser thermal angioplasty alone for 25 grafts, including 16 polytetrafluoroethylene (PTFE) grafts, eight saphenous vein grafts, and one externally supported (EXS) Dacron graft in which the stenotic lesions were detected by deterioration of the Doppler flow waveform pattern or a significant fall in the ankle/brachial pressure index (ABPI). Follow-up was from 3 to 24 months (average of 9 months) for PTFE grafts, from 5 to 21 months (average of 11 months) for saphenous vein grafts, and 13 months for the EXS Dacron graft following femorodistal artery reconstructions. Stenotic lesions were most common in the distal anastomotic sites: 11 PTFE grafts, three saphenous vein grafts, and one EXS Dacron graft. Among these, 13 grafts showed a type II flow waveform pattern at the time of surgery. Clinical success was achieved in 12 of the PTFE grafts (75%), in five of the vein grafts (62.5%), and in the single EXS Dacron graft. Four PTFE and three saphenous vein grafts failed subsequent to repeat intraoperative balloon angioplasty in three and graft extension in three and one graft interposition.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1993

Management of concomitant abdominal aortic aneurysm and gastrointestinal malignancy.

Selecting the most appropriate surgical approach for patients with abdominal aortic aneurysm (AAA) and gastrointestinal malignancy remains controversial. In an attempt to develop guidelines for the management of patients with these two simultaneous lesions, a retrospective review of patients who had concomitant AAA and gastrointestinal malignancy was undertaken. During the period from January 1985 to February 1993, 229 patients with AAA were admitted to our hospital. Among these, 19 patients (8%) had a gastrointestinal malignancy together with AAA and were divided into 2 groups. Group I was composed of 11 patients who underwent either a 1- or a 2-stage operation for both lesions. Group II was composed of eight patients who either underwent an operation for one lesion (six patients) or did not have any operation (two patients). Among group I, six patients underwent the two-stage operation. In four of the six patients, the malignancy was resected first. In the remaining two patients, the aneurysmectomy was performed first, because, in one patient, the aneurysm was more than 6 cm in diameter, and, in the other patient, the aneurysm was a saccular type. Among group I, five patients (two patients with gastric cancer, and one patient each with esophageal cancer, rectal cancer, and malignant lymphoma of the stomach) underwent a one-stage operation. In three of the five patients (two patients with gastric cancer and one patient with esophageal cancer), simultaneous resection was carried out by using segregated approaches, namely, the retroperitoneal approach for AAA and the transperitoneal approach for malignancy. Although the clinical characteristics of the patients were different, 8 of the 11 patients (73%) in group I are still alive, whereas only 1 of the 8 patients (13%) in group II is still alive. The principles of our surgical approaches for concomitant AAA and gastrointestinal malignancy are as follows: (1) The lesion that absolutely indicated urgent surgery was resected first. (2) If both lesions were asymptomatic, the malignancy was resected first. (3) Simultaneous resection using different approaches was useful in some patients with concomitant upper early gastrointestinal malignancy. (4) Both lesions need to be resected eventually for better long-term survival.

Aortic Aneurysm, Abdominal↗

PubMed1993

Correlation of long-term results of extra-anatomic bypass and flow waveform analysis.

To investigate the correlation between the long-term results of an extra-anatomic bypass and operative flow waveform analysis, we retrospectively reviewed 32 axillofemoral and 21 femorofemoral bypasses for between 1 and 5 years after surgical repair. For the grafts with a type O or I flow waveform pattern, the patency at 3 years (83%) and at 5 years (83%) was superior to grafts with a type II flow waveform (69 and 60%). For the axillofemoral bypass grafts with a type O or I waveform, the patency rate was 92% at 5 years. In contrast with the type II flow, the patency rate was 70% at 5 years. For the femorofemoral bypass with a type O or I and a II flow waveform, the patency at 4 years was 67 and 46%, respectively. In cases with concomitant superficial femoral artery occlusion, the flow waveform was type O or I in 23% and type II in 77%. The patency rate at 5 years was 85% for cases with a patent superficial femoral artery, and 51% for an occluded superficial femoral artery (p < 0.05). These results suggest that the long-term outcome of extra-anatomic bypass correlates with the operative flow wave analysis. In addition, good long-term results and an accurate flow wave pattern depend on the distal run-off, particularly the presence of a patent superficial femoral artery.

Adult↗

PubMed1993

Natural course of endothelium-dependent and -independent responses in autogenous femoral veins grafted into the arterial circulation of the dog.

We examined the natural course of endothelium-dependent and -independent responses in reversed autogenous vein grafts during regeneration and tissue repair processes after vein grafting in dogs. Vein grafts implanted in the canine femoral artery were removed, cut into rings, and suspended in organ chambers for isometric tension recording at 3 days and 1, 2, 4, and 6 weeks after implantation. Endothelial cells were denuded from some rings. Control veins were taken from nonsurgically treated femoral veins. Acetylcholine caused endothelium-dependent relaxations in the control veins, whereas in the vein grafts there was no evidence of endothelium-dependent relaxations to acetylcholine 3 days after the operation. Acetylcholine caused endothelium-independent contractions throughout the study. The endothelium-dependent responses to ADP and calcium ionophore A23187 were constantly maintained. Three days after the operation, the amplitude of norepinephrine-induced contractions of the vein grafts was impaired, and at 1 week the amplitude was recovered, although it was significantly smaller than the amplitude of contractions of the control veins at any postoperative period. Endothelium-independent relaxations to sodium nitroprusside were maintained throughout the study. Thus, there was a selective loss of acetylcholine-mediated relaxation in vein grafts in the early postoperative stage, a time when the intima is not thickened. These altered responses in vein grafts in the early postoperative period may have a role in graft failure.

Animals↗

PubMed1993

Graft replacement of pararenal inferior vena cava for leiomyosarcoma with the use of venous bypass.

Total replacement of the inferior vena cava across the renal vein confluence was successfully performed under venovenous bypass in a patient with primary leiomyosarcoma of the inferior vena cava. Concomitant resection of metastases by right nephrectomy, partial hepatectomy, and cholecystectomy allowed recurrence-free survival for the past 20 months. To the best of our knowledge, this is the first report of successful replacement of the inferior vena cava for a primary tumor.

Female↗

PubMed1993

Laparoscopic ligation of splenic artery aneurysm.

Efforts should be made to avoid splenectomy because host resistance is maintained by the spleen. We describe here a 50-year-old woman in whom laparoscopic ligation of a splenic artery aneurysm 3.0 cm in diameter was successfully performed, without major complications. Computed tomography performed 5 months later revealed no infarction in the spleen. For this patient with liver cirrhosis and cholelithiasis, laparoscopic cholecystectomy was performed at the same operation. Laparoscopic surgery is most feasible when the splenic artery is markedly tortuous and protrudes from the pancreas.

Aneurysm↗

PubMed1993

Impaired endothelial prostacyclin production of the canine vein graft in a poor distal runoff limb.

BACKGROUND: Because blood flow modulates endothelial prostacyclin production, the extent of this production in autologous vein grafts implanted in poor distal runoff limbs needed to be examined. METHODS: Endothelial prostacyclin production in canine autologous vein grafts was measured in poor distal runoff limbs (poor runoff group) and compared with findings in normal runoff limbs (control group). Vein grafts were perfused in a closed circuit at 3 days and 1, 2, 3, and 4 weeks after implantation; after perfusion for the first 30 minutes in a steady flow (basal prostacyclin production), the grafts were exposed to arachidonic acid (stimulated prostacyclin production) for the following 30 minutes. Prostacyclin, as the metabolite 6-keto-PGF1 alpha, was radioimmunoassayed. RESULTS: Basal and stimulated prostacyclin production increased in both groups during a period of time after implantation. At 2 weeks when endothelialization was complete, prostacyclin production in the poor runoff group was impaired, compared with the findings in the control group, and this difference increased with time. At 4 weeks the stimulated prostacyclin production was 18.91 +/- 4.03 ng/cm2 in the control group and 11.60 +/- 1.67 ng/cm2 in the poor runoff group (p < 0.05). CONCLUSIONS: We propose that the impaired capacity of the vein graft to produce prostacyclin in a poor distal runoff may lead to loss of graft patency in reconstructed arteries.

Animals↗

PubMed1992

High aortic occlusion associated with lupus anti-coagulant.

Lupus anti-coagulant (LAC) has been recognised in association with venous and arterial thrombotic events. We retrospectively investigated the relationship between LAC and 21 patients with juxtarenal high aortic occlusion. Four of the 21 patients were LAC positive (19%), one of whom was a woman suffering from systemic lupus erythematosus (SLE). The three men had neither SLE nor any other connective tissue disease. The mean age of the four patients was 43.5 years and three of them (75%) were younger than 50 years of age. By contrast, the mean age of the 17 patients without LAC was 59.9 years and 14 of them (82.4%) were older than 50 years. The postoperative courses in all four patients with LAC undergoing arterial reconstructions were uneventful. Two patients were treated by either anti-coagulation or anti-platelet agents, postoperatively. The present paper demonstrates for the first time that, in patients with juxtarenal high aortic occlusion, the incidence of LAC positivity is higher in younger patients (below 50) than in older patients (above 50). In addition, our results show that a preoperative evaluation of the presence of LAC is required in cases with juxtarenal high aortic occlusion, particularly when the partial thromboplastin time (PTT) is prolonged and the patients are younger than 50 years old.

Adult↗

PubMed1992

Rupture of embolised coeliac artery pseudoaneurysm into the stomach: is coil embolisation an effective treatment for coeliac anastomotic pseudoaneurysm?

An elderly woman with an anastomotic pseudoaneurysm of the coeliac artery, after previous treatment of a thoraco-abdominal aortic aneurysm, was treated by stainless steel coil embolisation. One year later, the embolised pseudoaneurysm ruptured into the stomach and total gastrectomy and aneurysmorraphy was necessary. She is leading a normal life 6 months later.

Aged↗

PubMed1992

The potential risk for subclavian vein occlusion in patients on haemodialysis.

Subclavian vein (SCV) stenosis or occlusion can be a late complication of temporary haemodialysis or following catheterisation for intravenous hyperalimentation. In five patients with prior catheterisation or trauma of the SCV, incapacitating oedema of the upper extremity developed only after the creation of ipsilateral arteriovenous (AV) fistulas for haemodialysis. The duration of the previous catheterisation was 2 to 4 weeks. Massive upper extremity oedema developed at 10 days to 22 months with an average of 11 months after the establishment of AV fistulas. Subclavian-axillary vein bypass using a ringed polytetrafluoroethylene graft was successful for one patient and ligation of the AV fistulae led to good results for the other three. In planning vascular access procedures in the upper extremity, venography should be mandatory to try to prevent such complications if a previous history of subclavian catheterisation exits.

Aged↗

PubMed1992

Simultaneous resection of abdominal aortic aneurysms and early gastric cancer by retroperitoneal and transperitoneal approach.

The surgical approach to patients with abdominal aortic aneurysm and gastrointestinal malignancy remains controversial. We experienced two cases with abdominal aortic aneurysm and gastric cancer, which were treated by a one-stage operation using a different approach. At first, the operation for the aneurysm was done through a retroperitoneal approach and then, a partial gastrectomy for gastric cancer was done through a transperitoneal approach. The postoperative course of both cases was uneventful. The patients were discharge on the 19th and 21st postoperative days, respectively. This one-stage operation using different isolated approaches, such as the retroperitoneal approach for abdominal aortic aneurysm and transperitoneal approach for gastric cancer, was useful for the patients with abdominal aortic aneurysm and particularly early gastric cancer in terms of preventing an infection of the prosthetic graft.

Adenocarcinoma↗

PubMed1992

Possible role of cytomegalovirus in the pathogenesis of inflammatory aortic diseases: a preliminary report.

To search for possible evidence of a relationship between human cytomegalovirus and aortic diseases, we examined 41 aortic lesions excised at surgery and 16 aortic tissues obtained at autopsy for the presence of cytomegalovirus DNA, by use of polymerase chain reaction. Cytomegalovirus DNA was present in seven (88%) of eight lesions of inflammatory aortic diseases with periaortic fibrosis, five of six inflammatory aneurysms, and all of two aortic occlusive lesions with inflammation. Cytomegalovirus DNA was detected in 20 (61%) of 33 atherosclerotic aneurysms, whereas it was detected in only five (31%) of 16 autopsy samples that showed neither inflammation nor atherosclerosis. Thus the possibility that cytomegalovirus may play a role in the pathogenesis of inflammatory aortic diseases warrants further attention.

Adult↗

PubMed1991

Isotopic study of the effects of platelets on development of intimal thickening in autologous vein grafts in dogs.

The effects of platelets on the development of intimal thickening of arterially transplanted autologous vein grafts was investigated using canine poor run-off models. A new apparatus consisting of a shielding lead block to measure in vivo platelet adherence only on the intima of the vein graft was developed. In 23 dogs, 51Cr-labelled platelets (20 microCi/kg) were injected and isotope emission over the grafts was counted. Platelet adherence was expressed as the thrombocyte accumulation index (TAI), i.e. the ratio of counts over the graft under an abnormal flow condition in the poor run-off model to those over the graft under normal flow conditions of the contralateral leg. The TAI of the total graft (TTAI) was significantly high immediately and on the first and third days after implantation. The TAIs of the proximal (PTAI) and distal (DTAI) portions of the vein graft were also high at these same times. At 7, 10, 14 and 21 days, the TAI was almost equal to 1.0, a time at which endothelial regeneration was complete as confirmed by scanning electron microscopy. Thus, the prominent intimal thickening of arterially transplanted autologous vein grafts in dogs, induced under an abnormal flow condition, correlates well with the enhanced platelet adherence on the intima of the vein grafts in an early period after implantation.

Animals↗

PubMed1991

Endothelium-derived relaxing factor and vein grafts.

Platelet thrombosis, intimal hyperplasia and progression of atherosclerosis are the most important factors determining the patency of vein grafts for arterial occlusive disease. Interactions between aggregating platelets and the vessel wall play an important role in all of these processes. Recently, it has become evident that the endothelium modulates the underlying vascular smooth muscle by releasing an endothelium-derived relaxing factor, a potent vasodilator and anti-aggregating substance. Little information is available, however, on such endothelial functions of autogenous vein grafts. This review focuses on vascular modulation by endothelium-derived relaxing factor in vein grafts.

Adenosine Diphosphate↗

PubMed1991

Intraoperative flow waveform analysis aids in preventing early graft failure following reconstruction of arteries of the legs.

To enable early detection and treatment of vascular defects leading to early graft failure, intraoperative flow waveform analyses were carried out during lower extremity arterial reconstructions in 226 patients undergoing 102 aortoiliac/femoral and 124 femorodistal bypass grafts. Flow waveform types III or IV indicated early graft failure. These were noted in seven grafts (6.9%) in the aortoiliac/femoral position and in eight grafts (6.5%) in the femorodistal position. The main cause of the abnormal flow waveform pattern was misinterpretation of preoperative arteriographic findings in aortoiliac/femoral reconstructions and technical errors in anastomoses in femorodistal reconstructions. Of 15 grafts with an abnormal flow waveform pattern, 13 were effectively repaired with patch angioplasty, graft extension, or replacement with thrombectomy. In two grafts, the repair failed and amputation had to be done. Thus, intraoperative flow waveform analysis is a simple, useful, and safe method to detect vascular defects leading to early graft failure. Unless assessment of preoperative arteriographic findings in aortoiliac/femoral reconstructions are accurate and anastomotic techniques in femorodistal reconstructions are refined, early graft failure may occur.

Aged↗