Evaluation of intercellular lipid lamellae in the stratum corneum by polarized microscopy.

BACKGROUND: Intercellular lipids contain a lamellar structure that glows in polarized images. It could be expected that the intercellular lipid content be estimated from the luminance values calculated from polarized images of stratum corneum strips. Therefore, we attempted to develop a method for simple and rapid evaluation of the intercellular lipid content through a procedure. Herein, we demonstrated a relationship between the luminance value and the amount of ceramides, one of the main components of intercellular lipids. MATERIALS AND METHODS: The stratum corneum was collected from the forearm using slides with a pure rubber-based adhesive, which did not produce unnecessary luminescence under polarizing conditions. Images were analyzed using luminance indices. The positive secondary ion peak images were obtained using the time of flight-secondary ion mass spectrometry; the polarized and brightfield images were obtained using a polarized microscope. The ceramide and protein amount was measured by high-performance liquid chromatography and bicinchoninic acid protein assay after microscope imaging. Images and quantitative values were used to construct evaluation models based on a convolutional neural network (CNN). RESULTS: There was a correlation between the highlighted areas of the polarized image to overlap with the area where ceramide-derived peak was detected. Evaluation of the CNN-based model of the polarized images predicted the amount of ceramides per unit of stratum corneum. CONCLUSION: The method proposed in the study enabled a large number of specimens to provide a simple, rapid, and efficient evaluation of the intercellular lipid content.

Noncontact measurement of cardiac beat by using active stereo with waved-grid pattern projection.

We propose a method to observe cardiac beat from 3D shape information of body surface by using the active stereo with waved-grid pattern projection, and report preliminary experiments to evaluate validities of the proposed method. By comparing results of our method with those of electrocardiogram (ECG), we confirmed sufficient correspondences between peak intervals of depth changes between contiguous frames measured by the active stereo and R-R intervals measured by ECG. We proposed the visualization of the spatial distribution of depth change plotted on the 3D shape of chest surface. We confirm that the spatial phase difference, which is caused by heart pump ability, appears in the 3-D shape change of chest surface.

Proposal on 3-D endoscope by using grid-based active stereo.

In this paper, we propose a novel 3-D endoscope system by using grid-based active stereo. In the proposed system, projection of a waved-grid pattern that consists of vertical and horizontal sinusoidal lines realizes accurate shape acquisition in sub-pixel accuracy. We develop a small pattern projector implementable to a head of a ready-made endoscope, and examine 3-D shape reconstruction by actual equipment. As the result of the measurement for a known-shaped object, which is a hexagonal cylinder, the error of length measurement is below 0.9% and the error of angle measurement is below 2.2%. We make a measurement of animal organ meat, and confirm that the system can reconstruct a 3-D shape of the organ surface.

Optimal dose and injection duration (injection rate) of contrast material for depiction of hypervascular hepatocellular carcinomas by multidetector CT.

PURPOSE: The aim of this study was to investigate the optimal dose and injection duration of contrast material (CM) for depicting hypervascular hepatocellular carcinomas (HCCs) during the hepatic arterial phase with multidetector row computed tomography (CT). MATERIALS AND METHODS: The study population consisted of 71 patients with hypervascular HCCs. After unenhanced scans, the first (early arterial phase, or EAP), second (late arterial phase, or LAP), and third (equilibrium phase) scanning was started at 30, 43, and 180 s after injection of contrast material (CM). During a 33-s period, patients with a body weight < or =50 kg received 100 ml of non-ionic CM with an iodine concentration of 300 mg I/ml; patients whose body weight was >50 kg received 100 ml of CM with an iodine concentration of 370 mg I/ml. First, we measured enhancement in the abdominal aorta and tumor-to-liver contrast (TLC) during the EAP and LAP. Next, to investigate the relation between aortic enhancement and TLC during the LAP, two radiologists visually assessed the conspicuity of hypervascular HCCs during the LAP using a 3-point scale: grade 1, poor; grade 2, fair; grade 3, excellent. Finally, to examine the effect of the CM dose and injection duration on aortic enhancement during the EAP, we simulated aortic enhancement curves using test bolus data obtained for 10 HCC patients and the method of Fleischmann and Hittmair. RESULTS: A relatively strong correlation was observed between aortic enhancement during the EAP and TLC during the LAP (correlation coefficient r = 0.75, P < 0.001). The 95% confidence intervals for the population mean for aortic enhancement during EAP in patients with tumor conspicuity grades of 1, 2, and 3 were 188.5, 222.4; 228.8, 259.3; and 280.2, 322.5 HU (Hounsfield Unit), respectively. Thus, we considered the lower limit of the aortic enhancement value for excellent depiction of HCCs during EAP to be 280 HU. To achieve an aortic enhancement value of >280 HU for aortic enhancement simulations during EAP, the injection duration should be <25 s for patients receiving a CM dose of 1.7 ml/kg with 300 mg I/ml iodine and <30 s for those receiving 2.0 ml/kg. CONCLUSIONS: For excellent depiction of hypervascular HCCs during the hepatic arterial phase, the injection duration should be <25 s in patients receiving a CM dose of 1.7 ml/kg with 300 mg I/ml iodine and <30 s for patients receiving 2.0 ml/kg.

A semiautomated technique for evaluation of uterine peristalsis.

PURPOSE: To evaluate the capability of a newly developed semiautomatic analysis technique for evaluation of uterine peristalsis in comparison with visual assessment. MATERIALS AND METHODS: Cine magnetic resonance (MR) images were obtained from 16 normal volunteers in periovulatory phase. Sixty-eight studies were evaluated by both visual evaluation and by a semiautomated computer assisted software. The software was developed by applying an automated contour tracking method and enables objective analysis of frequency, amplitude, velocity, and direction. Assessments were based on: 1) the recognition of peristalsis, 2) peristaltic direction and frequency, and 3) the way of recognizing peristaltic direction. The data obtained by both modalities were compared with those of previously reported ultrasound (US) findings. RESULTS: Uterine peristalsis was identified in all studies by both objective and visual analyses. There was no significant difference in the identification of peristalsis, recognition of peristaltic directions, or peristaltic frequency (P > 0.05). Data were well in accordance with those in US literature. Peristaltic direction was recognized either by configuration change in the endometrium or by conduction of low signal intensity in the subendometrial myometrium and there was statistically no difference. CONCLUSION: Evaluation of uterine peristalsis by the semiautomatic analysis accorded well with the results obtained visual assessments and previous US findings.