Search PubMed⌕ Search

Biomedical subjects

K Esato

Publications and source records attributed to K Esato.

At least 145 records · Page 8Linked to original sources
PubMed1997

SPECT with In-111 autologous platelets to detect residual splenic tissue in two patients with relapsed thrombocytopenia.

In two patients with relapsed thrombocytopenia, the authors used SPECT with In-111 labeled autologous platelets to identify residual splenic tissue after splenectomy. One case involved a previously splenectomized patient with idiopathic portal hypertension, while the other had relapsed chronic idiopathic thrombocytopenic purpura (ITP). In both patients, SPECT showed a higher In-111 uptake in the splenic tissues compared with planar images. In the patient with ITP, a small accessory spleen had been overlooked on abdominal CT because of post-operative changes, but it was identified by superimposition of SPECT/CT images. These cases indicate that In-111 platelet SPECT is useful in detecting and localizing residual accessory splenic tissue associated with relapsed thrombocytopenia.

Adult↗
PubMed1997

Radionuclide imaging in emphysema after lung volume reduction surgery.

Three dimensional (3D) surface displays of dynamic Xe-133 and Tc-99m MAA SPECT were performed to evaluate regional lung function in two patients with pulmonary emphysema before and after thoracoscopic lung volume reduction surgery. The 3D displays were reconstructed using a color-illuminated, surface-rendering technique. For the Xe-133 studies, a fusion display of 3D equilibrium (EQ) and 3-minute washout (WO) images was used to show the distribution of Xe-133 retention, which were transparently seen within the entire lung contours delineated by the EQ image. In both patients, these 3D displays allowed an overview of the localized poorly functioning lungs with Xe-133 retention or reduced perfusion with geometric realism. The location and extent were more easily comprehended on the displays compared to the slice-by-slice presentations of tomograms. Postoperatively, the displays efficiently revealed restored function in the remaining lungs. The 3D surface displays of the two SPECT procedures providing topographic information of regional lung function appears to contribute to the treatment strategy of this surgery.

Aged↗
PubMed1997

Three-dimensional surface displays of perfusion SPET in the evaluation of patients with pulmonary emphysema for thoracoscopic lung volume reduction surgery.

A modified, three-dimensional display was applied to 99Tcm-macroaggregated albumin (99Tcm-MAA) SPET to help assess the effect of thoracoscopic lung volume reduction surgery (LVRS) on regional lung perfusion. Surface-rendered three-dimensional images for 99Tcm-MAA and xenon-133 (133Xe) equilibrium (EQ) SPET were obtained in 11 patients with pulmonary emphysema before and after LVRS. A single three-dimensional fusion display of both images was then reconstructed, and the perfused lungs were transparently visible through the lung contours delineated by the three-dimensional 133Xe EQ image. The extent of preserved perfusion in the lung (the perfusion index) was estimated using the ratio (%) of the total pixel numbers of the segmented perfusion data to those of the 133Xe lung volume data. The three-dimensional fusion display provided an overview of the distribution of hypoperfusion in the lungs with geometric realism and enhanced the perception of anatomic size and configuration compared with multiple tomograms and three-dimensional perfusion images without superimposition of three-dimensional 133Xe image. Post-operatively, it displayed restored perfusion in the remaining lungs, and changes in the perfusion index correlated with %FEV1 (r = 0.731, P = 0.0001) more closely than the perfusion data alone (r = 0.593, P < 0.01). This method is useful for directing LVRS and assessing its effectiveness, as it provides precise tomographic information on regional perfusion.

Aged↗
PubMed1997

Abdominal aortic aneurysm: rupture associated with the high-attenuating crescent sign.

PURPOSE: To determine the histopathologic features of the ruptured abdominal aortic aneurysm associated with the high-attenuating crescent sign on computed tomographic (CT) scans and to suggest a possible mechanism for the rupture. MATERIALS AND METHODS: Histopathologic examination was performed with specimens from six patients with a ruptured aneurysm associated with the high-attenuating crescent sign and from eight patients with a nonruptured aneurysm and in whom the high-attenuating crescent sign was not present. RESULTS: Acute hemorrhage in the mural thrombus or aneurysmal wall coincident with the high-attenuating crescent sign was present in all six patients with a ruptured aneurysm. Clefts with seeping blood in the mural thrombus were seen in four patients with a ruptured aneurysm; intact specimens of the mural thrombus were not obtained in two patients because the hemorrhagic thrombus was fragile. Clefts with seeping blood were scattered from the inner to the outer layers of the mural thrombus. In the eight patients with uncomplicated aneurysm, no hemorrhage in the mural thrombus or aneurysmal wall was noted, and no clefts were seen. CONCLUSION: The cause of high-attenuating crescents in a ruptured aneurysm may be attributed to hemorrhage in the mural thrombus or in the aneurysmal wall.

Adult↗
PubMed1997

[Usefulness of 3-D dynamic pulmonary xenon-133 SPECT for thoracoscopic lung volume reduction surgery in patients with pulmonary emphysema].

Six patients with pulmonary emphysema scheduled to undergo thoracoscopic lung volume reduction surgery (TLVRS) were evaluated by three-dimensional (3-D) dynamic pulmonary xenon-133 SPECT. Serial 30-second dynamic SPECT data for equilibrium and washout (for 5 min) were acquired using a continuous repetitive rotating acquisition mode with a triple-detector SPECT system. SPECT data were reconstructed to 3-D images with a color, surface-rendering technique, and a 3-D fusion image of the 3-min washout image over the equilibrium image was obtained. Regional ventilation was visually assessed on the fusion 3-D images and quantified by xenon-133 half-washout time (T1/2) and mean transit time (MTT). The 3-D fusion image localized and lateralized the worst diseased sites with xenon-133 retention. Xenon-133 retention, T1/2 and MTT were reduced on these images in five patients with improved pulmonary function tests following TLVRS. However, xenon-133 retention was greater in one with asynchronous diaphragm movement after TLVRS. This modality will assist TLVRS in determining the lung resection target and in evaluating the treatment effect.

Endoscopy↗
PubMed1997

[Lymph node dissection during a video-assisted lobectomy is inferior to that in a standard lobectomy].

The indications for a video-assisted lobectomy are currently ill-defined. Clinicians recommend based on the extent of lymph node involvement. Fifty-nine patients with clinical stage I non-small cell lung cancer underwent lobectomies with systemic lymph node dissections through a standard thoracotomy (Group C), and 26 patients underwent lobectomies with lymph node dissections using the video-assisted procedure (Group V). The number of dissected lymph nodes at all node levels were compared between the two groups. There was no significant difference between groups in the total number of dissected lymph nodes in patients with right lung cancer. The number of dissected hilar and interlobar lymph nodes, however, was less in Group V than that in Group C (hilar: 1.2 +/- 0.4 vs. 2.8 +/- 0.6, interlobar: 1.1 +/- 0.4 vs. 2.1 +/- 0.4). The total number of dissected lymph nodes in patients with left lung cancer was significantly less in Group V than that in Group C (18.5 +/- 0.3 vs. 28.7 +/- 2.4). In addition, the number of dissected lymph nodes in pratracheal, pretracheal, tracheobronchial, subcarinal, hilar, and interlobar lymph nodes were significantly less in the group V than those in Group C. Although there was no significant difference in the actual survival rates between the groups in this preliminary study, a sufficiently small number of dissected lymph nodes in the video-assisted lobectomy may have resulted in inaccurate staging and poor prognosis in these patients.

Aged↗
PubMed1997

[Influence of cardiopulmonary bypass on lymphocyte function].

It is known that lymphocyte function is impaired after cardiopulmonary bypass (CPB). In this study, the lymphocyte stimulation test (LST) with PHA was used before and after CPB in 28 adult patients, and compared with the surgical parameters and serum cytokine (IL-6, IL-8) levels. LST was impaired after CPB in all patients. Although this value usually recovered by the third postoperative day (POD); (normal group, n = 16), some patients showed prolonged duration of the impaired LST (delayed group, n = 12). Therefore, the parameters of surgery, white blood cell (WBC) count, lymphocytes and subsets, and serum cytokine levels were compared between the normal and the delayed groups. There was no significant difference in the number of WBCs or lymphocytes between these two groups. OKT4-positive cells were reduced on the first POD in both groups, and in the normal group, the number of OKT4-positive cells recovered more quickly than in the delayed group. Serum IL-6 and IL-8 levels in the delayed group were elevated after CPB, and were significantly higher in the delayed group than in the normal group. In conclusion, patients who showed prolonged impairment of lymphocyte function may be partly due to prolonged CPB.

Adult↗
PubMed1996

Pancreatoblastoma: case report and review of treatment in the literature.

A case of pancreatoblastoma arising from the body-to-tail of the pancreas in a 5-year-old boy is presented. The patient underwent exploratory laparotomy and, 11 days later, resection of the tumor (partial pancreatectomy, pyloroplasty, and splenectomy). Before resection, cyclophosphamide and vincristine were administered. Because of tumor spillage during resection, a combination of chemotherapy (administration of cyclophosphamide and adriamycin on that day) and postoperative radiotherapy was given. Nine months after resection, partial hepatectomy was performed for liver metastasis and consolidated by a more intensive chemotherapy regimen using cisplatin, adriamycin, vincristine, and cyclophosphamide. After completion of the chemotherapy, the patient had a 14-month uneventful course, and a locally recurrent tumor was treated by the fourth surgery (extirpation of the recurrent tumor, partial hepatectomy, partial colectomy, and partial gastrectomy) and intraoperative radiation. Thereafter, the boy has shown no evidence of disease at 3 years 8 months. The literature of pancreatoblastoma is reviewed from the therapeutic viewpoint.

Child, Preschool↗
PubMed1996

Changes in angiographic features and the ankle/brachial pressure index of femorodistal arterial bypass grafts during knee flexion.

Systolic ankle pressure was measured in limbs in the extended and 90 degrees-flexed positions in three groups of patients who had undergone below-knee femorodistal arterial bypass. Group 1 consisted of eight limbs in seven patients who had received an autologous saphenous vein (ASV) graft; group 2 consisted of seven limbs in seven patients who had received a ringed expanded polytetrafluorethylene (ePTFE) graft; and group 3 consisted of five limbs in five patients who had received a reinforced biosynthetic borine collagen vascular (Omniflow) graft. Intravenous digital subtraction angiography was performed within 3 months of implantation. The ankle/brachial index (ABI) was significantly lower when the knee was flexed than when it was extended in group 1 and 3, but not in group 2. The ABI flexion in group 1 was similar to that in group 2. Morphologic changes such as kinking were demonstrated angiographically in groups 1 and 3. Given that the ABIs in groups 1 and 2 were similar with the knee flexed, despite the morphologic changes in group 1, we concluded that saphenous vein and ringed ePTFE grafts are more durable when subjected to acute knee flexion than Omniflow grafts. Thus, as graft failure is unlikely to result from kinking as a result of knee flexion alone, further clinical studies are required to elucidate the precise causes of graft failure.

Aged↗
PubMed1996

Successful management of a giant spinal arteriovenous malformation with multiple communications between primitive arterial and venous structures by embolization: report of a case.

A 47-year-old woman was admitted to our hospital with a giant spinal arteriovenous malformation (AVM) causing heart failure and thoracic myelopathy. Angiography revealed that the spinal AVM had multiple feeding vessels branching from the 5th through 12th intercostal arteries. The drainage vein flowed to the azygos vein and superior vena cava. The AVM destroyed the 7th thoracic vertebra. The cardiac output was 16.7l/min and the shunt ratio was 64% before treatment. Embolization with cyanoacrylate was performed because the operation was considered to be associated with a significant risk of paraplegia and organ ischemia. The cardiac output decreased to 11.6l/min and the shunt ratio was reduced to 32%. After embolization the patient demonstrated no symptoms of either heart failure or sensory deficits. During embolization, provocative tests using sodium amytal and lidocaine with magnetic stimulation were also performed. The above findings suggest that provocative tests and magnetic stimulation are useful to predict paraplegia, which could result from embolization while, in addition, embolization is considered to be a useful treatment for multiple shunt and nidus in this region.

Angiography↗
PubMed1996

Disadvantages of muscle-sparing thoracotomy in patients with lung cancer.

At our institute patients with lung cancer had traditionally undergone lobectomy with mediastinal lymph node dissection using a standard posterolateral approach. The considerable morbidity associated with the standard posterolateral thoracotomy led us to investigate an alternative muscle-sparing approach. A prospective, randomized study of 30 patients with primary lung cancer (stage I or II) was performed to compare the following: operative field size, number of dissected lymph nodes, surgery time, postoperative pain, shoulder range of motion, and pulmonary function test results between patients who underwent either standard thoracotomy (SP group, n = 15) or the muscle-sparing thoracotomy (MS group, n = 15). The procedure should provide enough operative field size to access to mediastinum. Compared with the standard posterior thoracotomy, the muscle-sparing thoracotomy supplied a smaller operative field (218 +/- 31 versus 165 +/- 41 cm2) and required more surgery time (87 +/- 13 minutes) than the standard posterior thoracotomy (66 +/- 12 minutes). There were no significant differences in the number of dissected mediastinal lymph nodes. During the early postoperative days, pain and restriction of shoulder flexion were significantly less in the MS group than in the SP group. There were no significant differences in pulmonary function between the two groups. In terms of the operative field there is a marked disadvantage with the muscle-sparing incision compared with standard thoracotomy. The operative field is significantly smaller than with a standard thoracotomy, requiring more time to dissect the mediastinum; however, the pain is less and shoulder range of motion is superior to what is seen after standard thoracotomy during the early postoperative period. We conclude that there is no overall advantage to using the muscle-sparing incision in patients with lung cancer.

Female↗
PubMed1996

Surgical repair of a coronary sinus diverticulum not associated with Wolff-Parkinson-White syndrome.

Diverticulum of the coronary sinus is rare. A 58-year-old man without Wolff-Parkinson-White syndrome underwent repair of a coronary sinus diverticulum accompanies by mitral regurgitation. The coronary sinus diverticulum had been identified 6 years earlier and had enlarged over time. At surgery, the neck of the diverticulum was closed, and the mitral valve replaced with a CarboMedics prosthetic valve (diameter, 29 mm). This the first case report of the surgical repair of a coronary sinus diverticulum not associated with Wolff-Parkinson-White syndrome.

Coronary Angiography↗
PubMed1996

Effect of cardioplegic arrest and reperfusion on coronary reserve and autoregulation.

BACKGROUND: The effects of cardioplegic arrest and reperfusion on the coronary vasculature remain to be characterized. This study was designed to investigate changes in coronary reserve and autoregulation after hypothermic cardioplegic arrest and reperfusion. METHODS: Isolated rabbit hearts were perfused in a retrograde manner with Krebs-Henseleit bicarbonate buffer solution at a pressure of 80 cm H2O. Baseline measurements were performed for (1) coronary flow; (2) vasodilatory response to 5-hydroxytryptamine (10(-7) mol/L) and nitroglycerin (10(-4) mol/L); (3) autoregulatory capacity, quantified as closed-loop gains; and (4) isovolemic left ventricular function. Hearts were then subjected to cardioplegic arrest for 90 minutes. Twenty minutes after reperfusion, measurements were repeated. RESULTS: Coronary flow decreased significantly after reperfusion (6.2 +/- 1.1 versus 5.3 +/- 1.1 mL.min-1.g-1; p < 0.01). The response to 5-hydroxytryptamine as percentage increase of flow decreased significantly after reperfusion (134.0% +/- 12.0% versus 109.1% +/- 6.8%; p < 0.01). However, there was no significant change in the response to nitroglycerin after reperfusion (121.3% +/- 17.6% versus 136.6% +/- 13.3%). The closed-loop gain demonstrated negative values before arrest but became positive after reperfusion, indicating loss of autoregulation after reperfusion. There was no significant change in left ventricular function. CONCLUSIONS: The coronary flow reserve in response to 5-hydroxytryptamine and autoregulation were impaired after cardioplegic arrest and reperfusion, whereas nitroglycerin-induced vasodilatory response and left ventricular function were preserved.

Animals↗
PubMed1996

Granulocyte phagocytic function is impaired during cardiopulmonary bypass.

BACKGROUND: The presence of impaired phagocytic function of the reticuloendothelial system after cardiac operations using cardiopulmonary bypass remains controversial. METHODS: In this study, the phagocytic function of granulocytes in 14 patients undergoing cardiac operations with cardiopulmonary bypass was examined using a chemiluminescence method. Seven patients with abdominal aortic aneurysms served as controls. Electron microscopy also was employed to evaluate morphologic changes. RESULTS: The 14 cardiac patients showed impaired phagocytic function from immediately after operation until 12 hours after the operation. This phagocytic function recovered within 24 hours. The 7 control patients showed no change in phagocytic function during or after the operation. Scanning electron microscopic examination of the cardiac patients' granulocytes revealed the loss of villi on cell surfaces immediately after operation. However, these villi were restored within 24 hours after the operation. CONCLUSIONS: The phagocytic function of granulocytes was impaired in the early postoperative period in patients undergoing cardiopulmonary bypass, and this was probably due to the loss of villi on granulocyte surfaces.

Aged↗
PubMed1996

Effect of E5510 on anastomotic intimal hyperplasia and platelet aggregation in dogs.

We examined the effect of an antiplatelet agent, E5510, which inhibits both platelet aggregation and release of platelet-derived growth factor (PDGF), on anastomotic intimal hyperplasia and platelet aggregation. Twenty Beagle dogs underwent infrarenal aortic reconstruction with an expanded polytetrafluoroethylene (ePTFE) graft 5 mm in diameter and 3 cm long. The dogs were divided into three groups: placebo (control group, 7 dogs), E5510 1 mg/day (1-mg group, 6 dogs), and E5510 4 mg/day (4-mg group, 7 dogs). E5510 was administered orally 2 h before operation and once daily for 3 months after operation. Grafts were harvested 3 months after operation. All 13 grafts in the treated groups remained patent without evidence of intimal hyperplasia, whereas only 4 of 7 grafts (57%) remained patent in the control group, including 1 graft with > 50% stenosis. Three occluded grafts showed severe intimal hyperplasia at the anastomoses. The platelet aggregation ratio (PAR) with collagen (100 micrograms/ml) before drug administration at 3 months in the 4-mg group was significantly lower than that in the control and 1-mg groups. PAR after drug administration at 3 months in the 1- and 4-mg groups was significantly lower than that in the control group. Intimal thickness at the distal anastomosis was 817 +/- 190 microns in the control group, 240 +/- 80 microns in the 1-mg group, and 197 +/- 28 microns in the 4-mg group. Intimal thickness in the control group was significantly greater than that in the 1- and 4-mg groups. Smooth muscle cell (SMC) values in the intima at the distal anastomosis were 65.6 +/- 4.4% extinction (%E) in the control group, 47.6 +/- 3.4%E in the 1-mg group, and 51.3 +/- 3.5%E in the 4-mg group. SMC value in the control group was significantly greater than that in the 1- and 4-mg groups. E5510 inhibited PAR and reduced the degree of anastomotic intimal hyperplasia.

Anastomosis, Surgical↗
PubMed1996

Is it possible to differentiate malignant mediastinal nodes from benign nodes by size? Reevaluation by CT, transesophageal echocardiography, and nodal specimen.

STUDY OBJECTIVE: To reevaluate whether it is possible to reliably differentiate malignant mediastinal lymph nodes from benign nodes by size, and to determine the frequency of metastases to normal-sized mediastinal lymph nodes that directly affects the sensitivity for detecting malignant mediastinal lymph nodes (N2 nodes) on CT. DESIGN: Prospective study of patients with non-small cell lung cancer. SETTING: Department of Radiology and First Department of Surgery, Yamaguchi University School of Medicine. PATIENTS: We examined 40 patients with non-small cell lung cancer, who underwent thoracotomy because of operable stage (stage I, II, IIIA) in preoperative staging, using CT and transesophageal echocardiography (TEE). INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Lymph nodes 10 mm or greater in short-axis diameter on CT and TEE were considered abnormal. Furthermore, lymph node size was measured by TEE and nodal specimens in long- and short-axis diameter in each patient. Two hundred eight mediastinal lymph nodes were dissected and N2 nodes were present in 28% of patients (11/40); in 7 of these 11 patients (64%), mediastinal lymph node metastases were misdiagnosed on CT because of normal-sized N2 nodes. Furthermore, in 73% of N2 nodes, nodal size was normal on TEE. There were no significant difference in both diameters between malignant mediastinal lymph nodes and benign nodes on TEE and nodal specimens. CONCLUSIONS: It is not possible to reliably differentiate malignant mediastinal nodes from benign nodes by size alone, and we should be aware of high frequency of normal-sized N2 nodes in patients with operable stage of lung cancer.

Adult↗