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Background: Corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP) each have distinctive clinical features, but diagnosis is often uncertain. Our purpose was to evaluate whether localized, single-voxel proton magnetic resonance spectroscopy ( 1 H-MRS) could distinguish between typical CBD and PSP patients. Methods:The study included 10 patients with CBD, nine with PSP and eight agematched normal healthy subjects. A single-voxel method of 8 cm 3 (2 ¥ 2 ¥ 2 cm) was used for 1 H-MRS. The volume of interest was selected at the frontoparietal cortex and the lentiform nucleus.Results: Patients with CBD had significantly reduced ratios of N-acetylaspartate to choline-containing compounds (NAA/Cho), N-acetylaspartate to creatine and phosphocreatine (NAA/Cr) in the frontoparietal cortex and lentiform nucleus compared with the normal subjects. Patients with PSP had significantly reduced NAA/Cho and NAA/Cr ratios in the lentiform nucleus, but not in the frontoparietal cortex compared with normal subjects. There was a significant difference in the NAA/Cho in the frontoparietal lobe between CBD and PSP patients.Conclusion: 1 H-MRS may indicate different regional patterns of neuronal involvement in CBD and PSP. We suggest that this could be helpful in the differentiation and diagnostic evaluation of CBD and PSP patients.

Soft copy reading of digital images has been practiced commonly in the PACS environment. In this study, we compared liquid-crystal display (LCD) and cathode-ray tube (CRT) monitors for detection of pulmonary nodules and interstitial lung diseases on digital chest radiographs by using receiver operating characteristic (ROC) analysis. Digital chest images with a 1000x1000 matrix size and a 8 bit grayscale were displayed on LCD/CRT monitor with 2M pixels in each observer test. Eight and ten radiologists participated in the observer tests for detection of nodules and interstitial diseases, respectively. In each observer test, radiologists marked their confidence levels for diagnosis of pulmonary nodules or interstitial diseases. The detection performance of radiologists was evaluated by ROC analyses. The average Az values (area under the ROC curve) in detecting pulmonary nodules with LCD and CRT monitors were 0.792 and 0.814, respectively. In addition, the average Az values in detecting interstitial diseases with LCD and CRT monitors were 0.951 and 0.953, respectively. There was no statistically significant difference between LCD and CRT for both detection of pulmonary nodules (P=0.522) and interstitial lung diseases (P=0.869). Therefore, we believe that the LCD monitor instead of the CRT monitor can be used for the diagnosis of pulmonary nodules and interstitial lung diseases in digital chest images.

The ability to predict hazards in possible situations in a general X-ray examination room created for Kiken-Yochi training (KYT) is quantified by use of free-response receiver-operating characteristics (FROC) analysis for determining whether the total number of years of clinical experience, involvement in general X-ray examinations, occupation, and training each have an impact on the hazard prediction ability. Twenty-three radiological technologists (RTs) (years of experience: 2–28), four nurses (years of experience: 15–19), and six RT students observed 53 scenes of KYT: 26 scenes with hazardous points (hazardous points are those that might cause injury to patients) and 27 scenes without points. Based on the results of these observations, we calculated the alternative free-response receiver-operating characteristic (AFROC) curve and the figure of merit (FOM) to quantify the hazard prediction ability. The results showed that the total number of years of clinical experience did not have any impact on hazard prediction ability, whereas recent experience with general X-ray examinations greatly influenced this ability. In addition, the hazard prediction ability varied depending on the occupations of the observers while they were observing the same scenes in KYT. The hazard prediction ability of the radiologic technology students was improved after they had undergone patient safety training. This proposed method with FROC observer study enabled the quantification and evaluation of the hazard prediction capability, and the application of this approach to clinical practice may help to ensure the safety of examinations and treatment in the radiology department.