Change in portal vein hemodynamics after chemoembolization for hepatocellular carcinoma: evaluation through multilevel dynamic multidetector computed tomography during arterial portography.

Objective: This study aimed to clarify the effect of embolization with lipiodol on portal vein hemodynamics.

Methods: Time-density curves of the main portal vein on multilevel dynamic multidetector computed tomography during arterial portography were used to analyze peak computed tomography value (PV), time to PV (TPV), arrival time of contrast medium at the main portal vein (ATMPV), slope [(PV - 150) / (TPV - ATMPV)], and slope ratio (slope after embolization / slope before embolization).

Results: In 20 patients with hepatoma, ATMPV and TPV were significantly prolonged and the time-density curve slope was significantly less after embolization.

Radiation dose to rectum in high-dose-rate brachytherapy with a single implant and two fractions for prostate cancer, and its prediction by prostate volume.

We aimed to clarify the differences between the estimated rectal dose (ERD) and the first measured dose (FMD) and second measured dose (SMD) to the rectum during high-dose-rate (HDR) brachytherapy, and to predict FMD from the prostate volume (PV) or the rectal dose-volume parameters (RDVPs). ERD, FMD, and SMD were assessed with a rectal dosimeter during HDR brachytherapy of 18 Gy given in two fractions to 110 patients (48 hormone recipients, 62 hormone-naïve patients) with prostate cancer. The correlations between FMD and PV, and between FMD and RDVP (D 2ml-D 5ml) were investigated.

Volume-rendered hemorrhage-responsible arteriogram created by 64 multidetector-row CT during aortography: utility for catheterization in transcatheter arterial embolization for acute arterial bleeding.

Aortography for detecting hemorrhage is limited when determining the catheter treatment strategy because the artery responsible for hemorrhage commonly overlaps organs and non-responsible arteries. Selective catheterization of untargeted arteries would result in repeated arteriography, large volumes of contrast medium, and extended time. A volume-rendered hemorrhage-responsible arteriogram created with 64 multidetector-row CT (64MDCT) during aortography (MDCTAo) can be used both for hemorrhage mapping and catheter navigation.

Comparison of air kerma between C-arm CT and 64-multidetector-row CT using a phantom.

Purpose: To compare air kerma after scanning a phantom with C-arm CT and with 64-multidetector row CT (64MDCT).

Materials And Methods: A phantom was scanned using parameters based on data of ten patients with hepatocellular carcinoma who had C-arm CT during hepatic arteriography and 64MDCT during arterial portography. Radiation monitors were used to measure air kerma ten times at each of five points: the center (A), top (B), left side (C), bottom (D), and right side (E).

Optimal scanning timing by use of multi-detector row computed tomography during thoracic aortography for depiction of arteries causing hemoptysis.

Scanning timing for multi-detector row computed tomography during thoracic aortography (MDCT-TA) was explored for depiction of arteries responsible for hemoptysis. The mean time (MT) from contrast medium (CM) injection to peak enhancement (PE) in the descending aorta at the level of the diaphragm on thoracic aortography was investigated. The MT to PE of the descending aorta at the level of diaphragm was 4.

Hepatoma feeding arteriogram created by CT during aortography using IVR 64-multidetector-row CT for catheterization in transcatheter arterial chemoembolization for hepatocellular carcinoma.

CT during aortography (CTAo) using IVR 64-multidetector-row CT (IVR-64MDCT) enables the rapid and simultaneous depiction of both the hepatic and extrahepatic feeding arteries in hepatocellular carcinoma (HCC), and can be achieved using a reasonable volume of contrast medium. The scan time is approximately 6 s from the diaphragm to the kidney using CTAo with 64MDCT with a slice thickness and slice interval of 0.5 mm.

Optimum CT reconstruction parameters for vascular and hepatocellular carcinoma models in a liver phantom with multi-level dynamic computed tomography with 64 detector rows: a basic study.

We quantified to clarify the optimum factors for CT image reconstruction of an enhanced hepatocellular carcinoma (HCC) model in a liver phantom obtained by multi-level dynamic computed tomography (M-LDCT) with 64 detector rows. After M-LDCT scanning of a water phantom and an enhanced HCC model, we compared the standard deviation (SD, 1 ± SD), noise power spectrum (NPS) values, contrast-noise ratios (CNR), and the M-LDCT image among the reconstruction parameters, including the convolution kernel (FC11, FC13, and FC15), post-processing quantum filters (2D-Q00, 2D-Q01, and 2D-Q02) and slice thicknesses/slice intervals. The SD and NPS values were lowest with FC11 and 2D-Q02.

Optimal injection rate and volume of contrast medium for observing hemodynamics of a hepatocellular carcinoma structure model.

This study aimed to identify the optimal concentration, injection rate, and total volume of contrast medium (CM) for evaluating the hemodynamics of a hepatocellular carcinoma (HCC) structure model of diameter 35 mm, using multi-level dynamic computed tomography (M-LDCT) with 64 detector rows. A tube was inserted in the model as a simulated vessel. Five CM concentrations were used: non-diluted, 2-, 3-, 6-, and 9-fold diluted.

Optimal contrast material concentration for distinguishing among carotid artery lumen, carotid stent, and neck in cone-beam computed tomography during carotid angiography: basic and clinical studies.

Purpose: To explore the optimal contrast material (CM) concentration for distinguishing CM, carotid stent (CS), and neck components in cone-beam computed tomography (CBCT) during carotid angiography (CBCT-CA).

Materials And Methods: A neck phantom containing CS and contrast-filled imitation vessels of 9 mm diameter was scanned using CBCT. CM (300 mgI/ml) was used in concentrations of 100, 50, 33, 10, 5, and 1%.