Predictors of angle widening after laser iridotomy in Chinese patients with primary angle-closure suspect using ultrasound biomicroscopy

AIM:To assess the predictive value of baseline parameters of ultrasound biomicroscopy(UBM) for angle widening after prophylactic laser peripheral iridotomy(LPI) in patients with primary angle-closure suspect(PACS).METHODS:Angle-opening distance(AOD),trabecular iris angle(TIA),iris thickness,trabecular-ciliary process angle,and trabecular-ciliary process distance were measured using UBM performed before and two weeks after LPI.Iris convexity(IC),iris insertion,angulation,and ciliary body(CB) size and position were graded.Uni-and multivariate regression analyses were used to determine factors predicting the change in AOD(ΔAOD500,calculated as an angle width change before and after LPI) in all quadrants and in subgroup quadrants based on IC.RESULTS:In 94 eyes of 94 patients with PACS,LPI led to angle widening with increases in AOD500 and TIA(P<0.01).Multivariable regression analysis showed that IC(P<0.001),CB position(P=0.007) and iris insertion(P=0.049) were significantly predictive for ΔAOD500.All quadrants were categorized into extreme IC(27.8%),moderate IC(62.3%),and absent IC(9.9%) subgroups.The AOD500 increased by 220% and no other predictive factor was found in the extreme IC quadrants.The AOD500 increased by 55%,and baseline iris angulation was predictive for smaller changes in ΔAOD500 in the moderate IC quadrants.CONCLUSION:In PACS patients,quadrants with greater iris bowing predict substantial angle widening after LPI.Quadrants with a flatter iris,anteriorly positioned CB,and basal iris insertion are associated with less angle widening after LPI.Quadrants with iris angulation as well as a flatter iris configuration predict a smaller angle change after LPI.

Robust Lane Detection and Tracking Based on Machine Vision

Lane detection based on machine vision,a key application in intelligent transportation,is generally characterized by gradient information of lane edge and plays an important role in advanced driver assistance systems(ADAS).However,gradient information varies with illumination changes.In the complex scenes of urban roads,highlight and shadow have effects on the detection,and non-lane objects also lead to false positives.In order to improve the accuracy of detection and meet the robustness requirement,this paper proposes a method of using top-hat transformation to enhance the contrast and filter out the interference of non-lane objects.And then the threshold segmentation algorithm based on local statistical information and Hough transform algorithm with polar angle and distance constraint are used for lane fitting.Finally,Kalman filter is used to correct lane lines which are wrong detected or missed.The experimental results show that computation times meet the real-time requirements,and the overall detection rate of the proposed method is 95.63%.

An effective and safe gastric endoscopic submucosal dissection in the right lateral position using an inverted overtube

Previously, we reported the efficacy of a newly developed inverted overtube in shortening the hemostatic time and obtaining a clear endoscopic view in emergency endoscopic hemostasis. This device also helped us to perform gastric endoscopic submucosal dissection(ESD) more safely by changing the direction of gravity in the right lateral position. To perform a safe ESD, it is important to make an appropriate angle and distance between the electric knife and the gastric mucosa. In this position, the distance to gastric mucosa is reduced, and the angle of the electric knife changes from vertical to somewhat oblique, facilitating safer cutting.

Optimal guidance of extended trajectory shaping

To control missile＇s miss distance as well as terminal impact angle, by involving the timeto-go-nth power in the cost function, an extended optimal guidance law against a constant maneuvering target or a stationary target is proposed using the linear quadratic optimal control theory.An extended trajectory shaping guidance（ETSG） law is then proposed under the assumption that the missile-target relative velocity is constant and the line of sight angle is small. For a lag-free ETSG system, closed-form solutions for the missile＇s acceleration command are derived by the method of Schwartz inequality and linear simulations are performed to verify the closed-form results. Normalized adjoint systems for miss distance and terminal impact angle error are presented independently for stationary targets and constant maneuvering targets, respectively. Detailed discussions about the terminal misses and impact angle errors induced by terminal impact angle constraint, initial heading error, seeker zero position errors and target maneuvering, are performed.