Shuji Abe

Histogram Analysis of Ventricular Enlargement on CT Images of Pediatric Hydrocephaly Patients

This study was performed to evaluate pediatric hydrocephaly patients with shunt failure. We objectively evaluated ventricular variations by head computed tomography (CT) analysis in which the histogram shape was compared between the normal and shunt failure states. To identify the characteristics of the histogram shape during ventricular enlargement in the presence of hydrocephaly, histograms in the normal state with favorable shunt function and ventricular enlargement were prepared for 6 hydrocephaly patients in whom visually apparent ventricular enlargement was noted on imaging, and alterations in the histogram shape with alterations in the ventricle size were investigated. When the ventricle enlarged, the convex or downward slope on the lower CT value side representing the ventricle rose on the histogram, while the convex on the higher CT value side representing the brain became smaller, suggesting that ventricular size changes can be judged objectively based on changes in the heights of the convex or downward slope on the lower value side and convex on the higher value side on histogram. The histogram shape in a state of ventricular enlargement was apparently different from that in the normal state. Histogram analysis of head CT images is useful for pediatric hydrocephaly patients.

Basic research on countermeasures against barium sulfate aggregation using a gastric phantom

The principal aim of this study was to conduct basic experiments to examine countermeasures against barium sulfate aggregation caused by denture adhesive in gastric cancer screening test. Experiment 1; barium sulfate aggregation was reconstructed in petri dishes and the degree of reducing aggregation by seven types of commercial drink and tap water was assessed visually. The most effective one was tap water. Experiment 2; two types of aggregation (severe and mild aggregation) were reconstructed using gastric phantom BMU-1, tap water of 30-150ml was added and the degree of reducing aggregation was assessed with the images. In the case of severe aggregation, the most effective quantity of tap water was 120 ml and the next was 150 ml with the following of 90, 60 and 30 ml (P < 0.05). In the case of mild aggregation, the order of effective quantity was 90, 60, 120, 30 and 150 ml (P < 0.05). The results of this study suggested that tap water drinking of the subject was effective for the reduction of barium sulfate aggregation in gastric cancer screening and the most effective quantity of tap water was 120 ml in the case of severe aggregation and 90 ml in the case of mild aggregation.

Effects of Bolus Volume on Geniohyoid Muscle Movement during Swallowing: Ultrasonographic M-Mode Study in Healthy Adults

Purpose: Videofluoroscopy is generally considered a “gold standard” technique for diagnosing dysphagia; however this technique exposes subjects to radiation. Ultrasonography is applied widely in clinical practice because of low cost, safety of the technique, and absence of radiation exposure. The purpose of this study was to investigate the application of B+M-mode ultrasound imaging as a new approach to quantify activity patterns of the geniohyoid muscles during swallowing and to assess the effect of bolus volume in healthy subjects.

Diagnostic Validity of High-Density Barium Sulfate in Gastric Cancer Screening by Record Linkage with the Osaka Cancer Registry –AUC Analyses of Sensitivity and Specificity on Sex and Ages of Subjects–

High-density barium sulfate (HDB) has been recommended by the Japanese Society of Gastroenterological Cancer Screening (JSGCS) and used in many medical facilities. However, it is not confirmed that the new method using HDB is superior in diagnostic validity compared to the conventional method using moderate-density barium sulfate (MDB). Pre viously, the authors reported that both methods showed simi lar validity in terms of sensitivity and specificity in gastric cancer screening. In this study, sensitivity and specificity were re-examined in more detail by area under receiver-operating characteristic (ROC) curves (AUC) analysis, especially on the sex (male, female) and the ages (>50, 55, 60, <60) of subjects. The results showed that the diagnostic validity of the method using HDB is almost same to that of the conven tional method using MDB. Clinical improvement in gastric cancer screening is in need of further studies on the new me thod using HDB.