257 A New Procedure and Concept of Helical Computed Tomography Dose Index (HTDI) in Dosimetry of Helical CT

A rigid motion correction method for helical computed tomography (CT).

We propose a method to compensate for six degree-of-freedom rigid motion in helical CT of the head. The method is demonstrated in simulations and in helical scans performed on a 16-slice CT scanner. Scans of a Hoffman brain phantom were acquired while an optical motion tracking system recorded the motion of the bed and the phantom. Motion correction was performed by restoring projection consist...

A reconstruction method for helical computed tomography

This paper presents a method for volumetric reconstruction from Helical Computerized Tomography (H-CT) data which are collected with a fan beam source. An interpretation of the HCT data in terms of the Axial Computerized Tomography (ACT) data is provided. This analysis indicates that the H-CT data for positive and negative detector angles can be combined to form periodically nonuniform hexagona...

Lung Cancer Screening by Helical Computed Tomography

Pitch dependence of longitudinal sampling and aliasing effects in multi-slice helical computed tomography (CT).

In this work, we investigate longitudinal sampling and aliasing effects in multi-slice helical CT. We demonstrate that longitudinal aliasing can be a significant, complicated, and potentially detrimental effect in multi-slice helical CT reconstructions. Multi-slice helical CT scans are generally undersampled longitudinally for all pitches of clinical interest, and the resulting aliasing effects...

a fundamental study of "histiriographic metafiction", and "literary genres", as introduced in "new historical philosophy", and tracing them in the works of julian barnes.

abstract a fundamental study of “historio-graphic metafiction” and “literary genres”, as introduced in “new historical philosophy”, and tracing them in the works of julian barnes having studied the two novels, the porcupine and arthur & george, by julian barnes, the researcher has applied linda hutcheon’s historio-graphic metafictional theories to them. the thesis is divided into five cha...