Comparison of CT artifacts and image recognition of various fiducial markers including two types of thinner fiducial markers for CyberKnife treatment.

AIM: The aim of the study was to evaluate computed tomography (CT) artifacts and image recognition of the CyberKnife system. Regarding fiducial markers, VISICOIL of 0.5 mm × 5.0 mm and 0.75 mm × 5.0 mm, ball-shaped Gold Anchor (GA) of 0.28 mm × 10 mm and 0.28 mm × 20 mm, were compared with the standard cylinder marker of 0.9 mm × 3.0 mm (ACCULOC). BACKGROUND: Recently, various kinds of commercial fiducial markers have been available in CyberKnife treatment. MATERIALS AND METHODS: The CT images of a water equivalent gel with each fiducial marker were acquired for the evaluation of CT artifacts. The evaluation was performed using the standard deviation of Hounsfield Unit (HU) value for a rectangle region near the fiducial marker. Then, to evaluate the image recognition, each fiducial marker was located to overlap in the target locating system (TLS) for the two sites; the vertebral bone and the pubic bone. RESULTS: For CT artifacts, the standard deviations of the VISICOIL of 0.5 mm × 5.0 mm was the smallest. The image recognition of four fiducial markers had a value close to the standard cylinder marker and was feasible for common use, but was slightly poorer when using GA of 0.28 mm × 10 mm in the dynamic conditions. CONCLUSION: Our results indicated that VISICOIL 0.5 × 5.0 mm and the GAs can be used nearly always for CyberKnife treatment in spite of their much thinner needles than those of cylinder types.

Eruption disturbance caused by an odontoma that was partially attached to the crown of the adjacent maxillary first molar, and step lesion excavation for the tooth preservation: A case report.

Despite the partial attachment of a complex odontoma to an impacted tooth, it is possible to guide the tooth to erupt normally and preserve it by step lesion excavation and the prevention of infection.

Random number generators tested on quantum Monte Carlo simulations.

We have tested and compared several (pseudo) random number generators (RNGs) applied to a practical application, ground state energy calculations of molecules using variational and diffusion Monte Carlo metheds. A new multiple recursive generator with 8th-order recursion (MRG8) and the Mersenne twister generator (MT19937) are tested and compared with the RANLUX generator with five luxury levels (RANLUX-[0-4]). Both MRG8 and MT19937 are proven to give the same total energy as that evaluated with RANLUX-4 (highest luxury level) within the statistical error bars with less computational cost to generate the sequence. We also tested the notorious implementation of linear congruential generator (LCG), RANDU, for comparison.

QSNPlite, a software system for quantitative analysis of SNPs based on capillary array SSCP analysis.

We present a newly developed software called "QSNPlite" that comprehensively interprets the data of SSCP and sequencing analyses obtained from capillary array electrophoresis systems used in the quantitative characterization of SNPs. QSNPlite assists in the genotyping of individuals with SNPs and in estimating the allele frequencies of SNPs using pooled DNA. We show that this estimation is accurate (mean absolute error, 1.4%) by comparing the results of the pooled analysis using QSNPlite with the true frequencies based on the allele counting after performing individual genotypings. The QSNPlite program runs on Windows XP and can be used to determine the allele frequencies of SNPs among a large number of individuals, such as in association studies of disease-responsible genes using the candidate gene approach.