Two mainland Japanese males were examined with a computer tomography (CT) X-ray scanner to reconstruct three-dimensional CT simulation images of their cranial anatomy and to check for the presence/absence of 23 nonmetric cranial traits. Surface anatomy for scoring 19 nonmetric cranial variations was clearly observed among the 23 variations. Evaluation of the four other traits might have been di...

conclusion scout views may be useful in determining dose and image quality in ct scanning; however, it is necessary to first determine the most appropriate scout view for ct scans. background while using the automatic exposure control technique in computed tomography (ct), the scout view determines the radiation dose for the ct scan by taking anatomical morphology into consideration. objectives...

A research prototype CT scanner is currently under development in our lab. One of the key components in this project is the CT detector. This paper describes the design and performance evaluation of the modular CT detector unit for our proposed scanner. It consists of a Photodiode Array Assembly which captures irradiating X-ray photons and converts the energy into electrical current, and a mini...

Since the development of the CT scanner, the faster scan time was the highest priority to achieve, and therefore, there have been a lot of efforts to reduce the scan time. The first generation CT scanner (Figure 1(a)) uses one pencil beam, and the projection data were acquired by translating the x-ray source and detector linearly. After the completion of the linear measurements, the x-ray sourc...

The monochromatic images acquired by Gemstone spectral imaging (GSI) mode on the GE CT750 HD theoretically determines the computed tomography (CT) number more accurately than that of conventional scanner. Using the former, the CT number is calculated from (synthesized) monoenergetic X-ray data. We reasoned that the monochromatic image might be applied to radiotherapy treatment planning (RTP) to...

Introduction: The use of a simple tissue analog material in the fabrication of medical computed tomography (CT) imaging phantoms has great potential to help researchers. The purpose of the present study is to develop new gel tissue-equivalent materials and determine whether their CT numbers and relative electron densities vary in CT images obtained by scans at different energie...

X-ray computed tomography (CT) systems with high resolution (also known as micro-CT systems) have been developed over the last two decades and have been used with great success in small animal studies. A micro-CT scanner is based on the same underlying physical principle as a clinical CT scanner, but it is designed for higher-resolution imaging. It produces three-dimensional (3D) tomographic da...

Methods Normally the 3D skull data from individual patients can be obtained from CT scanner. However, the overhead expenses and the maintenance costs of a CT machine have deterred many dentists and orthodontists from possessing the machine, so only a few orthodontists use the CT for diagnosis and treatment comparing to the x-ray images that are standard procedures for orthodontic measurements. ...

This contribution addresses the reduction of artifacts in cone-beam tomography (CT and SPECT/PET) that are caused by imperfect scanner mechanical alignment (i.e. misalignment). Such artifacts may show up as double contours, split edges, smearing, loss of resolution, change in magnification etc. Misalignment is a problem commonly recognized in SPECT/PET (see for example [12]) whereas in CT its i...