Biomedical subjects

Katsuhide Ito

Publications and source records attributed to Katsuhide Ito.

35 records · Page 2Linked to original sources

PubMed2003

Estimating the stenosis probabilities in arteriosclerosis obliterans using generalized estimating equations.

For each of 211 arteriosclerosis obliterans patients, the degree of stenosis of arteries at four sites were examined at Hiroshima University Hospital to analyse the relationship between the degree of stenosis and age, sex and site. The generalized estimating equations using a proportional odds model for the stenosis probability with exchangeable correlation was applied to this clustered, ordered polytomous data. Since the correlations between the responses were quite small, we could apply the independence estimating equations. The best mean model selected by Akaike information criterion suggested that age dependency of the stenosis probability was not observed in the central sites but was observed in the peripheral sites, and symmetry of the risk of stenosis was seen in the left and right sites. Details of the analysis will be described.

Adult↗

PubMed2003

[Is intravenous contrast enhancement effective in improving CT diagnosis of hepatic disease?].

PURPOSE: The purpose of this study was to evaluate the effectiveness of contrast enhancement in the diagnosis of hepatic disease. MATERIALS AND METHODS: 2761 cases involving CT of the liver and abdomen were analyzed using logistic analysis. CT was either helical-CT (SDCT) or multi-detector CT (MDCT), with power injector. RESULTS: Contrast enhancement use was 92% in liver disease and 95% in tumor cases. A typical case involved a 66-year-old man given 2-4 ml/sec of contrast material using dual injection. CT imaging was done in the equilibrium stage. The use of contrast material was effective for the diagnosis of liver tumor except in the qualitative diagnosis of hepatocellular carcinoma with SDCT where the odds ratio was 0.084. CONCLUSION: Intravenous contrast enhancement was effective for the CT diagnosis of hepatic tumor. Dynamic CT was effective using MDCT, and dual injection of contrast material was also valid for SDCT. Multiphasic studies were needed for detecting liver tumors not only on MDCT but also on SDCT. CT imaging during the equilibrium phase alone is inadequate to document diagnosis of metastatic liver tumors. The addition of various phasic contrast materials during CT was effective in evaluating liver tumors that showed angiogenesis.

Aged↗

PubMed2003

[Concurrent chemoradiation experience of recurrent gastric cancers resistant to TS-1].

We report our experience with concurrent chemoradiation for recurrent gastric cancers resistant to TS-1. From April 2000 to March 2003, we treated 10 consecutive patients with radiation and the concurrent single chemotherapy agent of TS-1 or CPT-11. Of the 10 patients, 3 (30%) had a complete response, 4 (40%) a partial response, and 3 (30%) stable disease, yielding an overall response rate of 70% (7/10). Three patients are alive and cancer-free, 5 patients died with cancers, and 2 patients are living with cancers as outpatients. The clinical benefit response was 90% (9/10). No patient has had either acute or late complication. Concurrent chemoradiation is feasible and seems to offer good results for recurrent gastric cancers resistant to TS-1.

Aged↗

PubMed2002

Use of multidetector row CT with volume renderings in right lobe living liver transplantation.

Multidetector row CT is a feasible diagnostic tool in pre- and postoperative liver partial transplantation. We can assess vascular anatomy and liver parenchyma as well as volumetry, which provide useful information for both donor selection and surgical planning. Disorders of the vascular and biliary systems are carefully observed in recipients. In addition, we evaluate liver regeneration of both the donor and the recipient by serial volumetry. We present how multidetector row CT with state-of-the-art three-dimensional volume renderings may be used in right lobe liver transplantation.

Blood Volume↗

PubMed2002

Hepatic arterial infusion of 5-fluorouracil and cisplatin for unresectable or recurrent hepatocellular carcinoma with tumor thrombus of the portal vein.

BACKGROUND AND OBJECTIVES: This study was designed to evaluate the efficacy of hepatic arterial infusion of 5-fluorouracil (5-FU) and cisplatin (CDDP) for unresectable or recurrent hepatocellular carcinoma (HCC) with tumor thrombus of the trunk or first branches of the portal vein (PVTT). METHODS: Seven unresectable or recurrent HCC patients with PVTT were enrolled in this study. A one-week course of chemotherapy consisted of intraarterial administration of CDDP (10 mg on days 1-5) for 1 h and 5-FU (250 mg on days 1-5) for 24 h, followed by cessation of administration for the subsequent 2 days (days 6 and 7). Three or more sequential courses of chemotherapy were given through an implanted reservoir. RESULTS: Serum alpha-fetoprotein (AFP) levels before the chemotherapy were >20 ng/ml in six of the seven patients. Serum AFP levels were decreased in four of the six patients after chemotherapy, including two patients (cases 1 and 7) whose AFP levels later returned to normal. Six of the seven patients had measurable lesions in the liver, with a response rate of 33%. In three of the seven patients (43%), PVTTs decreased in size or disappeared after chemotherapy. The mean and median survival periods of all patients were 8.0 and. 7.5 months, respectively. CONCLUSIONS: The chemotherapy described in this report is beneficial in terms of survival for HCC patients with PVTT for whom transcatheter arterial embolization or surgical treatment is contraindicated.

Aged↗

PubMed2002

Three-dimensional navigator for retroperitoneal laparoscopic nephrectomy using multidetector row computerized tomography.

PURPOSE: We evaluated the efficacy of a 3-dimensional (D) navigator for retroperitoneal laparoscopic nephrectomy. MATERIALS AND METHODS: A total of 21 patients with malignant localized renal (16) or ureteral (5) neoplasms underwent multi-detector row computerized tomography. The 3-D navigator was created using volume rendering technique. These findings were compared with videos obtained during laparoscopy. RESULTS: The 3-D navigator depicted all renal arteries (100% sensitivity) and 24 of the 25 renal veins (96% sensitivity). Hilar anatomy, including the tumor, major vessels and adrenal gland, and their relationships were visualized as in laparoscopic views. CONCLUSIONS: The 3-D navigator has a potentially important role in retroperitoneal laparoscopic nephrectomy. It is able to guide surgeons and aid in avoiding operative risks and possible complications.

Adult↗

PubMed2002

Comparison of small intestinal submucosa-covered and noncovered nitinol stents in sheep iliac arteries: a pilot study.

PURPOSE: To compare the biocompatibility and performance of nitinol endografts covered externally or internally with small intestinal submucosa (SIS) with bare nitinol stents in medium-sized arteries. MATERIALS AND METHODS: Eighteen nitinol Zilver stents were used: six externally SIS-covered endografts (ECEs), six internally SIS-covered endografts (ICEs), and six bare stents (BSs). Devices were implanted in the balloon-injured external iliac arteries (EIAs) of nine female sheep via carotid approach. Arteriograms were obtained before and after implantation and before animal sacrifice at 1, 3, and 6 months. Histologic studies of explanted specimens were performed. RESULTS: Implantation of all BSs, ECEs, and ICEs was successful, but slight luminal narrowing of 19% +/- 5.3% (range, 12%-28%) was seen in ICEs on postimplantation angiograms. At sacrifice, all six BSs and ECEs were patent, with BSs showing a mean angiographic luminal narrowing of 8.4% +/- 7.2% (range, 0%-18%) and ECEs showing a mean angiographic luminal narrowing of 16% +/- 7.5% (range, 6.5%-26%) as a result of neointimal hyperplasia. Four ICEs showed luminal narrowing of 21% +/- 17% (range, 0%-35%) as a result of marked neointimal hyperplasia and two were occluded, one at 3 months and the other at 6 months. ECEs and BSs showed approximately 80% lumen endothelialization at 1 month, which increased to 100% at 3 and 6 months. ICEs did not show complete endothelialization. CONCLUSION: The BS had the least vessel wall reaction. ECEs exhibited early endothelialization with early mild to moderate wall reaction decreasing at the late study stages. ICEs showed extensive wall reaction, possibly as a result of technical problems with SIS attachment.

Alloys↗

PubMed2002

Balloon-occluded retrograde transvenous obliteration of gastric fundal varices with hemorrhage.

OBJECTIVE: This study was performed to evaluate the clinical efficacy, feasibility, and complications of balloon-occluded retrograde transvenous obliteration for patients with hemorrhage from gastric fundal varices. SUBJECTS AND METHODS: Between December 1994 and February 2001, 24 consecutive patients with hemorrhage from gastric fundal varices were enrolled in this study. Balloon-occluded retrograde transvenous obliteration consisted of injecting 5% ethanolamine oleate iopamidol through the outflow vessels during balloon occlusion. The treatment was performed during acute bleeding in 11 patients and electively in 13 patients. Among those patients with acute bleeding, six were treated for temporary hemostasis with balloon tamponade, and five were treated endoscopically. RESULTS: Cannulation into the outflow vessels was performed in 23 patients, but the balloon catheter could not be inserted in one patient who had inferior phrenic vein outflow. Complete success was obtained in 88% (21/24) of patients, and partial success was obtained in two patients. In nine of 11 patients with acute bleeding, complete success was achieved. Rebleeding from gastric varices was not observed in patients treated with complete success, whereas two patients treated partially rebled within 1 week of the treatment (rate of rebleeding, 9%). Eradication of gastric varices was obtained in all patients (n = 19) who were examined by endoscopy 3 months after the treatment. Eight patients experienced worsening of esophageal varices. These patients were treated endoscopically because of findings that suggested a risk of hemorrhage. The overall mortality rate was 4% (1/24). No damage to the kidney was observed, although 11 patients had macrohematuria. CONCLUSION: Balloon-occluded retrograde transvenous obliteration followed by any hemostatic procedure might be effective for both prophylaxis of rebleeding and eradication of gastric fundal varices, even in urgent cases.

Adult↗

PubMed2002

A case of MELAS: hyperperfused lesions detected by non-invasive perfusion-weighted MR imaging.

We report a case of MELAS in which lesions were detected by perfusion-weighted MR imaging. Perfusion-weighted MRI using contrast media (PWI) and FAIR (flow-sensitive alternating inversion recovery), an arterial spin labeling method, clearly showed these lesions as hyperperfused areas. One of these lesions, diminished after steroid therapy, could also be detected by FAIR.

Adolescent↗

PubMedDate not supplied

Endovascular therapy for management of oral hemorrhage in malignant head and neck tumors.

PURPOSE: To evaluate the efficacy and safety of endovascular therapy in oral hemorrhage from malignant head and neck tumors. METHODS: Ten patients (mean age 56 years) with oral hemorrhage caused by malignant head and neck tumors underwent a total of 13 emergency embolization procedures using gelatin sponge particles, steel and/or platinum coils, or a combination of these embolic materials. Angiographic abnormalities, technical success rate, clinical success rate, recurrence rate, complications, hemostatic period, hospital days, survival days, and patient outcome were all analyzed. RESULTS: Angiographic abnormalities were identified during 85% of procedures (11/13). The technical success rate was 100% (13/13 procedures). The primary and secondary clinical success rates were 77% (10/13 procedures) and 67% (2/3 procedures), respectively. The overall clinical success rate was 92%, and the recurrence rate was 22% (2/9 procedures) in patients whom we were able to observe during the 1-month period after embolization. No major complications occurred. Several patients in whom gelatin sponge particles had been used complained of transient local pain after the procedure. The median hemostatic period was 71 days (range 0-518 days). Median hospital and survival days were 59 days (range 3-209 days) and 141 days (range 4-518 days), respectively. Three patients survived and 7 patients died during the observation period. Only 1 of these 7 patients died from hemorrhage. CONCLUSION: In conclusion, our findings suggest that endovascular therapy is an effective, safe, and repeatable treatment for oral hemorrhage caused by malignant head and neck tumors.

Adult↗

PubMedDate not supplied

Radiofrequency ablation therapy combined with cementoplasty for painful bone metastases: initial experience.

The purpose of this study was to assess the efficacy and safety of percutaneous radiofrequency (RF) ablation therapy combined with cementoplasty under computed tomography and fluoroscopic guidance for painful bone metastases. Seventeen adult patients with 23 painful bone metastases underwent RF ablation therapy combined with cementoplasty during a 2-year period. The mean tumor size was 52 x 40 x 59 mm. Initial pain relief, reduction of analgesics, duration of pain relief, recurrence rate of pain, survival rate, and complications were analyzed. The technical success rate was 100%. Initial pain relief was achieved in 100% of patients (n=17). The mean VAS scores dropped from 63 to 24 (p<0.001) (n=8). Analgesic reduction was achieved in 41% (7 out of 17 patients). The mean duration of pain relief was 7.3 months (median: 6 months). Pain recurred in three patients (17.6%) from 2 weeks to 3 months. Eight patients died and 8 patients are still alive (a patient was lost to follow-up). The one-year survival rate was 40% (observation period: 1--30 months). No major complications occurred, but one patient treated with this combined therapy broke his right femur 2 days later. There was transient local pain in most cases, and a hematoma in the psoas muscle (n=1) and a hematoma at the puncture site (n=1) occurred as minor complications. Percutaneous RF ablation therapy combined with cementoplasty for painful bone metastases is effective and safe, in particular, for bulky tumors extending to extraosseous regions. A comparison with cementoplasty or RF ablation alone and their long-term efficacies is needed.

Aged↗

PubMedDate not supplied

Massive hemorrhage from internal carotid artery pseudoaneurysm successfully treated by transcatheter arterial embolization with assessment of regional cerebral oxygenation.

A 54-year-old male presented with intermittent massive hemorrhage from recurrent oropharyngeal cancer. The angiogram showed the encasements at the main trunk of the left internal carotid artery (ICA) and external carotid artery (ECA). Transcatheter arterial embolization (TAE) of the ECA with gelatin sponge particles and microcoils was performed. However, hemorrhage recurred several hours after the initial TAE. The second angiogram showed a large pseudoaneurysm of the ICA developing at the encasement on the initial angiogram. As a simple neurologic test, regional cerebral oxygenation (rSO2) was assessed with and without manual compression of the common carotid artery (CCA). With compression of the left CCA, the rSO2 did not change. We therefore performed isolation of the pseudoaneurysm. We embolized proximally and distally to the ICA pseudoaneurysm with microcoils and the pseudoaneurysm disappeared. No major complications occurred and no massive hemorrhage recurred until death from the cancer. TAE was an effective treatment for massive hemorrhage caused by tumor invasion to ICA. Assessment of rSO2 was a simple and useful neurologic test predicting the cerebral blood flow to prevent complications of TAE.

Aneurysm, False↗

PubMedDate not supplied

Complications of transfemoral removal of percutaneous transfemorally implanted port-catheter systems.

Our purpose is to evaluate the feasibility and safety of the withdrawal procedure of percutaneous transfemorally implanted port-catheter systems. Thirty-seven patients (17.7%) underwent the withdrawal procedure of this port-catheter system among 209 patients. The reasons for withdrawal were as follows: termination of intra-arterial chemotherapy (n = 7), obstruction of hepatic artery (n = 5), port infection (n = 4), catheter infection (n = 4), catheter obstruction (n = 4), lower-limb palsy and pain (n = 2), exposure of the port due to skin defect (n = 2), patient's desire (n = 2), side effect of chemotherapy (n = 1), no effectiveness of chemotherapy (n = 1), hematoma at the puncture site (n = 1), duodenum perforation by the catheter (n = 1), intermittent claudication due to severe stenosis of right common iliac artery (n = 1), dissection of common hepatic artery (n = 1), and broken catheter (n = 1). In thirty-four of the 37 cases, the port-catheter system was successfully withdrawn without any complications. Clinical success rate was 91.9%. Complications occurred in three cases (8.1%), which were a pseudoaneurysm, thromboembolism of the right common iliac artery, and continuous bleeding from the subcutaneous pocket where the port system was placed for 1 month. In 15 cases, correction of the catheter tip or exchange for dislocation of the tip had to be done without withdrawal. It is not rare to withdraw port-catheter systems in cases of infection or hematoma around the system. Although withdrawal of a percutaneous transfemorally implanted port-catheter system is a relatively safe procedure, the port-catheter system should not be removed unless absolutely indicated.

Adolescent↗

PubMedDate not supplied

Technical innovation of cardiac multirow detector CT using multisector reconstruction.

Multisector reconstruction is a newly developed algorithm for multirow detector CT in cardiac study. Using volume data sets obtained by ECG-gated scanning, we can reconstruct cardiac images at any desired phase of the cardiac cycle retrospectively. In retro-processing multiplanar and three-dimensional images, thin-slice images with overlapping increment have a great advantage due to increasing z-axis resolution. In this article, we present principles of the algorithm, a phantom study, clinical applications and perspectives for the future.

Adult↗

PubMedDate not supplied

Coronary artery calcium scoring using multicardiac computed tomography.

OBJECTIVES: To test the hypothesis that multicardiac-phase computed tomography (CT) improves the quantification of coronary artery calcium. METHODS: Calcium-phosphate on a cardiac phantom and 108 calcified plaques from 50 patients were scanned, and multicardiac-phase images were obtained. Motion artifacts and calcium scores of the calcified plaques were compared between cardiac phases and CT scanners. RESULTS: In the phantom images, motion artifacts differed between cardiac phases; thus, the calcium scores were either higher or lower than the score from the static state. In the patient study, motion artifacts of calcifications on the various coronary branches varied with the cardiac cycle, which profoundly influenced the calcium scores. CONCLUSION: Multicardiac-phase CT has the potential to improve the quantification of coronary artery calcium by determining the cardiac phase where motion artifacts are the least on individual calcified plaques.

Aged↗

PubMedDate not supplied

Endovascular therapy of pulmonary arteriovenous malformations: Utility of 16-detector-row computed tomography pulmonary angiography as a pre-embolization survey.

The utility of computed tomography pulmonary angiography (CTPA) for coil embolization therapy of pulmonary arteriovenous malformations (PAVMs) was considered. Three consecutive patients (group A) with PAVMs underwent CTPA and coil embolization. The CTPA was performed using a 16-detector-row computed tomography scanner. After careful selection of pulmonary vessel trees, each feeding artery, nidus, and drainage vein was colored using different codes. By using the colored images, a 5-French catheter was shaped to fit to each feeding artery, the best fluoroscopic angle to select each feeding artery was chosen, and interlocking detachable coils (IDCs) were used in embolization. The procedure time and contrast material dose of group A were compared with those of the previous 3 patients (group B) who were treated by the conventional method. All PAVMs of both groups were completely embolized without coil migration. The average procedure time per lesion was 48.4 minutes for group A and 124.0 minutes for group B (P < 0.05). The average contrast material dose per lesion was 37.5 mL in group A and 76.0 mL in group B (P < 0.05). Using CTPA and IDCs, procedure time and contrast material dose were statistically significantly reduced. This combination therapy is useful in treating PAVMs less invasively.

Adult↗

PubMedDate not supplied

Super-selective transcatheter arterial embolization of a traumatic splenic arteriovenous fistula.

We report a 61-year-old woman with arteriovenous fistula (AVF) of a splenic artery caused by traumatic injury, which was successfully occluded by percutaneous transcatheter arterial embolization (TAE). We embolized the AVF with a coaxial system using six microcoils. This case suggests that super-selective TAE for traumatic AVF of a splenic artery is an effective and primary choice of first treatment. The use of a microcatheter and microcoils is an alternative to surgery.

Accidental Falls↗