Observation of posterior corneal vesicles with in vivo confocal microscopy and anterior segment OCT

The histopathology of posterior corneal vesicles (PCV) has not yet been revealed. A 15-year-old girl, who was diagnosed by slit-lamp microscopy as PCV, was examined using specular microscopy, in vivo confocal microscopy, and anterior segment OCT (optical coherence tomography). Anterior segment OCT showed that the thickness of both corneas was within normal limits. At the same time, in vivo confocal microscopy revealed endothelial cells in the rounded dark areas, acellular hyporeflective layers on the Descemet’s membrane, and hyperreflective linear lesions. These findings were not reported previously by slit-lamp and specular microscopy. The abnormal findings only existed at the Descemet’s membrane and corneal endothelial layer. Previous reports dealing with posterior polymorphous dystrophy (PPMD) examined using in vivo confocal microscopy reported almost the same findings, suggesting that PCV and PPMD may be the same at the microstructural level

Comparison of carbon dioxide and air insufflation use by non-expert endoscopists during endoscopic retrograde cholangiopancreatography

Background: Endoscopic retrograde cholangiopancreatography (ERCP) is subject to several complications that include a lengthy procedure time, technical difficulty, and active bowel movement induced by air insufflation. In ERCP carried out by non-expert endoscopists who are prone to excessive luminal insufflation, insufflation with carbon dioxide (CO2) may provide better and safer outcomes. We aimed to assess the efficacy and safety of CO2 insufflation during ERCP by non-expert endoscopists. Methods: This study included 208 consecutive patients who received ERCP, excluding those in poor general health or with obstructive lung disease. The first operator for each patient was a non-expert endoscopist having done 50 or fewer ERCP procedures. Primary outcomes were the changes in cardiopulmonary state during ERCP. Secondary outcomes were ERCP complications. We designed a single-center, randomized, prospective, double-blind, controlled trial with CO2 and air insufflation during ERCP. Results: CO2 insufflation did not affect overall procedure progression or results. A positive correlation was observed between procedure time and change in maximal systolic blood pressure from baseline among patients in the air insufflation group, but not in the CO2 insufflation group (correlation coefficient 0.408 vs 0.114, change in the maximal systolic blood pressure from baseline +4.2 vs+1.2mmHg/10min). This was consistent with our findings in patients treated by the first operator alone. The occurrence rate of post-ERCP pancreatitis tended to be lower in the CO2 group than the air group (4/102 [3.9%]vs 0/106 [0%], P=0.056). Conclusions: CO2 insufflation during ERCP by non-expert endoscopists is recommended from the standpoints of efficacy and safety.ArticleDIGESTIVE ENDOSCOPY. 25(2):189-196 (2013)journal articl

Video Observations of Tiny Near-Earth Objects with Tomo-e Gozen

We report the results of video observations of tiny (diameter less than 100 m) near-Earth objects (NEOs) with Tomo-e Gozen on the Kiso 105 cm Schmidt telescope. A rotational period of a tiny asteroid reflects its dynamical history and physical properties since smaller objects are sensitive to the YORP effect. We carried out video observations of 60 tiny NEOs at 2 fps from 2018 to 2021 and successfully derived the rotational periods and axial ratios of 32 NEOs including 13 fast rotators with rotational periods less than 60 s. The fastest rotator found during our survey is 2020 HS7 with a rotational period of 2.99 s. We statistically confirmed that there is a certain number of tiny fast rotators in the NEO population, which have been missed with any previous surveys. We have discovered that the distribution of the tiny NEOs in a diameter and rotational period (D-P) diagram is truncated around a period of 10 s. The truncation with a flat-top shape is not explained well either by a realistic tensile strength of NEOs or suppression of YORP by meteoroid impacts. We propose that the dependence of the tangential YORP effect on the rotational period potentially explains the observed pattern in the D-P diagram.Comment: This article is published in PASJ as open access, published by OUP (https://doi.org/10.1093/pasj/psac043). 27 pages, 16 figure