Three-dimensional radiochromic film dosimetry for volumetric modulated arc therapy using a spiral water phantom.

We validated 3D radiochromic film dosimetry for volumetric modulated arc therapy (VMAT) using a newly developed spiral water phantom. The phantom consists of a main body and an insert box, each of which has an acrylic wall thickness of 3 mm and is filled with water. The insert box includes a spiral film box used for dose-distribution measurement, and a film holder for positioning a radiochromic film.

[The protocol of dose reduction in liver perfusion computed tomography].

Cerebral perfusion computed tomography (CT) has been widespread, but abdominal perfusion CT has not been very popular because there has been a problem with regard to the limit of irradiation range and respiratory effects. Recently, it became easy to perform perfusion of abdominal organs because the use of multi detector row CT (MDCT) has been extensive. Along with it, the number of hospitals that perform liver perfusion CT has increased.

[Evaluation of magnetic resonance signal intensity in bone marrow after administration of super paramagnetic iron oxide (SPIO)].

Super paramagnetic iron oxide (SPIO) is taken up in the bone marrow and lymph nodes, as well as by the liver. Focusing on the intervertebral disks, which are unaffected by contrast effects, we examined the relationship between magnetic resonance image (MRI) signal intensity after SPIO uptake in the vertebral body and intervertebral disks and investigated MRI signal intensity in bone marrow metastases and osteomyelitic (inflammatory) lesions after SPIO uptake by bone marrow. The lumbar spine was imaged in 5 healthy volunteers (age range, 26-48 years).

[Impact of planning CT slice thickness on the accuracy of automatic target registration using the on-board cone-beam CT].

We have evaluated relationship between planning CT slice thickness and the accuracy of automatic target registration using cone-beam CT (CBCT). Planning CT images were acquired with reconstructed slice thickness of 1, 2, 3, 5, and 10mm for three different phantoms: Penta-Guide phantom, acrylic ball phantom, and pelvic phantom. After correctly placing the phantom at the isocenter using an in-room laser, we purposely displaced it by moving the treatment couch and then obtained CBCT images.

Role of Na+/L-carnitine transporter (OCTN2) in renal handling of pivaloylcarnitine and valproylcarnitine formed during pivalic acid-containing prodrugs and valproic acid treatment.

Pivalic acid and valproic acid decreases L-carnitine concentration in the body via urinary excretion of their acylcarnitines, pivaloylcarnitine (PC) and valproylcarnitine (VC). To obtain an information about the mechanism of the physiological response, we investigated the renal handling of these acylcarnitines by Na+/L-carnitine cotransporter, OCTN2 using the isolated perfused rat kidney, rat OCTN2 (rOCTN2) and human OCTN2 (hOCTN2) expressing cells. In the perfused rat kidney, PC and VC were strongly reabsorbed with an efficiency comparable to L-carnitine, and these reabsorption were inhibited by 1 mM L-carnitine, suggesting that the interaction of L-carnitine with PC and VC reabsorption would be responsible for renal handling of these acylcarnitines in rats.

Analysis of respiration-related movement of upper abdominal arteries: preliminary measurement for the development of a respiratory motion compensation technique of roadmap navigation.

In this study, we analyzed the respiratory motion of the upper abdominal arteries preliminary to developing a method of respiratory motion correction for the roadmap technique used in vascular interventions. We retrospectively obtained six digital angiography sequences taken during respiration. The levels of the right and left hemidiaphragms and the positions of artery bifurcation points were measured manually through each sequence.

Clinical evaluation of a newly developed method for avoiding artifacts caused by dental fillings on X-ray CT.

To evaluate the clinical usefulness of gantry tilt scanning as an image reconstruction technique for avoiding artifacts caused by metallic dental fillings. Gantry tilt scanning was used with multidetector-row computed tomography for imaging in patients with dental fillings. Using a novel PC-based program, the oblique images obtained were reconstructed to transverse images using nearest neighbor and bilinear interpolation methodologies in order to avoid metallic streak artifacts.

Leukemia inhibitory factor functions as a growth factor in pancreas carcinoma cells: Involvement of regulation of LIF and its receptor expression.

Leukemia inhibitory factor (LIF) is a pleiotrophic cytokine, which plays an important role in inducing cancer cachexia. We have previously reported that LIF promotes cell proliferation in some human carcinoma cells through c-fos, jun-B and cyclin-E expression. In the present study, we analyzed the regulation of LIF and its receptor (LIFR) expression in pancreatic carcinoma cells.

Cone-beam CT with flat-panel-detector digital angiography system: early experience in abdominal interventional procedures.

We developed a cone-beam computed tomography (CBCT) system equipped with a large flat-panel detector. Data obtained by 200 degree rotation imaging are reconstructed by means of CBCT to generate three-dimensional images. We report the use of CBCT angiography using CBCT in 10 patients with 8 liver malignancies and 2 hypersplenisms during abdominal interventional procedures.

[Evaluation of low contrast resolution in cone beam CT using FPD].

We examined the low contrast resolution of cone beam CT (CBCT) equipped with an indirect-type flat panel detector and compared it with a commercial CT unit (Robusto) . In CBCT, the X-ray tube voltage of 110 kV was used, and in the Robusto, the usual 120 kV was used for examinations. The computed tomography dose index (CTDI) of the two systems was measured, and images scanned at about the same exposure to radiation were compared.

[A design of the measuring chart for magnifying-power compensation in brain angiography].

Purpose: When brain angiography was performed, we devised the calculation theory for rectifying magnifying power, and produced the auxiliary tool.

Method: We produced the frame with a size of 300 x 300 x 15 mm from the thin board made from carbon. The frame is around arranged for every 1 cm in Pb-ball of the diameter of 1 mm.