Water-soluble polyvinyl alcohol microspheres for temporary embolization: development and in vivo characteristics in a pig kidney model.

Purpose: To preliminarily examine whether solubility of water-soluble polyvinyl alcohol (PVA) microspheres in blood plasma changes in proportion to their degrees of saponification. The study also examined their feasibility as a temporary embolic agents in the pig renal artery.

Materials And Methods: Three types of PVA microspheres with the degrees of saponification of 97 mol% (S97), 98 mol% (S98), and 99 mol% (S99) were prepared.

Transcatheter embolization for peripheral pseudoaneurysms with n-butyl cyanoacrylate.

The purpose of this study is to evaluate the clinical efficacy of transcatheter embolization for pseudoaneurysms of peripheral arteries with n-butyl cyanoacrylate (NBCA). From November 2000 to February 2008, 17 patients with 18 pseudoaneurysms were treated by transcatheter embolization at our affiliated hospitals. The locations of the pseudoaneurysms were right hepatic artery (n=3), renal artery (n=5), splenic artery (n=2), gastroduodenal artery (n=2), common hepatic artery (n=1), pancreatic arcade (n=1), external iliac artery (n=1), internal iliac artery (n=1), internal thoracic artery (n=1), and left gastric artery (n=1).

Mechanical characteristics of composite knitted stents.

We used metal wires and fibers to fabricate a composite knitted stent and then compare the mechanical characteristics of this stent with those of a pure metallic stent of the same construction in order to develop a stent that offers a comparable degree of expandability as metallic stents but can be used for highly curved lesions that cannot be treated using metallic stents. We fabricated two types of composite knitted stent (N-Z stents), using nitinol wire with a diameter of 0.12 mm and polypara-phenylene-benzobisoxazole (PBO) multifilament fiber (Zyron AS; Toyobo, Osaka, Japan).

Percutaneous translumbar inferior vena cava cannulation under computed tomography guidance.

Percutaneous translumbar inferior vena cava (IVC) cannulation is an alternative approach for central venous catheterization, but there have been sporadic reports of puncture-related complications. To avoid complications during IVC puncture, percutaneous translumbar IVC cannulation was performed under computed tomography (CT) guidance in addition to fluoroscopy in two patients. To perform chemotherapy for recurrent breast cancer, we planned subcutaneous port catheter placement for central venous access.

Peripheral stent placement in hemodialysis grafts.

The purpose of the present study was to evaluate the clinical outcome of peripheral stent placement after failed balloon angioplasty in patients with grafts who are on hemodialysis. We examined 30 Wallstents that were placed in 26 patients because balloon angioplasty failed or early restenosis (<3 months) occurred within 3 months. We retrospectively reviewed 267 consecutive balloon angioplasties performed in 71 patients with graft access between August 2000 and March 2007.

High-flow priapism undergoing arterial embolization: review of literature following American Urological Association guideline on the management of priapism.

We report herein a case of a patient with high-flow priapism for whom a gelatin sponge was used as a temporary occlusive agent in arterial embolization, resulting in favorable outcome. The American Urological Association guideline on the management of priapism recommends using temporary occlusive agents. We reviewed all reports published after the introduction of this guideline to compare temporary and permanent occlusive agents in terms of symptom improvement and onset of erectile dysfunction.

Intraosseous venography with carbon dioxide in percutaneous vertebroplasty: carbon dioxide retention in renal veins.

The objective of the present study was to determine the frequency of gas retention in the renal vein following carbon dioxide intraosseous venography in the prone position and, while citing references, to examine its onset mechanisms. All percutaneous vertebroplasties performed at our hospital from January to December 2005 were registered and retrospectively analyzed. Of 43 registered procedures treating 79 vertebrae, 28 procedures treating 54 vertebrae were analyzed.

Biochemical markers of bone turnover in percutaneous vertebroplasty for osteoporotic compression fracture.

Purpose: To evaluate relationships between biochemical markers of bone turnover, bone mineral density, and new compression fractures following vertebroplasty.

Methods: Initially, we enrolled 30 consecutive patients with vertebral compression fractures caused by osteoporosis. Twenty-three of the 30 patients visited our hospital for follow-up examinations for more than 4 weeks after vertebroplasty.

Relationship between cement distribution pattern and new compression fracture after percutaneous vertebroplasty.

Objective: The objective of this study was to prospectively investigate relationships between cement distribution patterns and the occurrence rates of new compression fractures after percutaneous vertebroplasty.

Subjects And Methods: Percutaneous vertebroplasty was performed for osteoporotic compression fractures in 76 consecutive patients. Patients were divided into two groups according to the cement filling pattern shown on radiography and CT: cleft pattern group (group C, n = 34), compact and solid cement filling pattern in vertebrae; and trabecular pattern group (group T, n = 42), sponge-like filling pattern.

Primary patency with cutting and conventional balloon angioplasty for different types of hemodialysis access stenosis.

Purpose: To compare primary patency rates of cutting balloon percutaneous transluminal angioplasty (PTA) (hereafter, cutting PTA) and conventional balloon PTA (hereafter, conventional PTA) in the treatment of different types of hemodialysis access stenosis.

Materials And Methods: The institutional review board approved this study. Written informed consent was obtained for the prospective component of this study and waived for the retrospective component.

Clinical assessment of percutaneous radiofrequency ablation for painful metastatic bone tumors.

Purpose: To investigate the pain-alleviating effects of radiofrequency ablation (RFA) on metastatic bone tumors in relation to tumor size, combined therapy, and percent tumor necrosis rate following RFA.

Methods: Subjects comprised 24 patients with 28 painful metastatic bone tumors. A 17G internally cooled electrode was inserted into the tumor for CT guidance and ablation was performed.

A case of spontaneous regression of hepatocellular carcinoma with multiple lung metastases.

Spontaneous regression of hepatocellular carcinoma (HCC) is a rare phenomenon. We present herein the case of a patient with hepatocellular carcinoma with multiple lung metastases in whom malignancy spontaneously regressed after taking Pheliinus linteus Mycelium. A 79-year-old man consulted our hospital complaining of epigastric discomfort.

Percutaneous vertebroplasty for osteoporotic compression fracture: multivariate study of predictors of new vertebral body fracture.

Purpose: To investigate the risk factors and relative risk of new compression fractures following vertebroplasty.

Methods: Initially, we enrolled 104 consecutive patients with vertebral compression fractures caused by osteoporosis. A total of 83 of the 104 patients visited our hospital for follow-up examinations for more than 4 weeks after vertebroplasty.

Percutaneous vertebroplasty: relationship between vertebral body bone marrow edema pattern on MR images and initial clinical response.

Purpose: To prospectively investigate the relationship between initial clinical response and bone marrow edema pattern on preprocedural magnetic resonance (MR) images in vertebral bodies selected for percutaneous vertebroplasty (PVP).

Materials And Methods: Institutional review board approval and written informed consent were obtained. PVP was performed for osteoporotic compression fractures in 80 consecutive patients (mean age, 72.

Radiological follow-up of new compression fractures following percutaneous vertebroplasty.

The purpose of the present study was to ascertain chronological changes in the analgesic effects of percutaneous vertebroplasty (PVP) on osteoporotic vertebral compression fractures and to radiologically follow new compression fractures after PVP. Seventy-six patients (206 vertebral bodies) were followed radiologically for a mean of 11.5 months.

Radiation exposure to operators during vertebroplasty.

Purpose: To measure the radiation received by physicians during percutaneous vertebroplasty with use of two types of injection devices with the interventional equipment guided by computed tomography (CT) and an angiographic/CT system.

Materials And Methods: Twenty consecutive patients who underwent percutaneous vertebroplasty were included in this study. The patients were divided into two groups, the 1-mL syringe group and the bone cement injector group.

Radiofrequency ablation combined with CO2 injection for treatment of retroperitoneal tumor: protecting surrounding organs against thermal injury.

Objective: The objective of this study was to separate target tumors from adjacent structures by injecting carbon dioxide (CO2) around the tumor to avoid thermal injury and the heat-sink effect from the blood vessel during percutaneous radiofrequency ablation.

Conclusion: We successfully achieved complete ablation of a retroperitoneal tumor without thermal injury. Imaging-guided percutaneous CO2 injection is useful for preventing thermal injury while achieving complete ablation of the tumor during radiofrequency ablation.

A new method for establishing an intrapulmonary tumor in the rabbit.

Objectives: Local treatments against malignant intrapulmonary tumors, such as radiotherapy, photodynamic therapy, and laser ablation therapy, are sometimes used in preference to surgery or chemotherapy. The efficacy of such treatments is dependent not only on the pathological type of the primary tumor, but also on loco-regional settings such as location of the lesion and relationship between the tumor and surrounding organs as well as tissues. Therefore, in order to evaluate the efficacy of a newly developed local treatment, it is essential to have a model in which a tumor can be established at an intended location.

A new bioabsorbable sleeve for staple-line reinforcement: report of a clinical experience.

Purpose: The most frequent and troublesome complication after resection of an emphysematous lung is persistent air leakage. This report describes our recent experience of using sleeves made of polyglycolic acid to reinforce staple-lines to reduce air leaks after resection of emphysematous lung.

Methods: We used bioabsorbable sleeves made of polyglycolic acid (PGA) for staple-line reinforcement during lung resections in 25 patients with emphysema.