A randomized study of network-based perception learning in the treatment of amblyopia children

AIM:To compare the effectiveness of network-based perception learning(NBPL) and traditional training in the treatment of amblyopia children.METHODS:This randomized controlled clinical trial recruited 56 participants aged 4-12 y with anisometropic and/or strabismic amblyopia. Participants were randomly divided into two groups:the NBPL group(n=28) who received patching and NBPL for 3 mo, and the control group(n=28) who got 3 mo of patching and traditional training. Best-corrected visual acuity(BCVA) in the amblyopic eye and stereoacuity were measured and compared at baseline, 1, 2, and 3 mo post-randomization.RESULTS:There were no significant differences in age, gender ratio, and BCVA between the two groups at baseline. At 3 mo, most patients gained lines(2 log MAR lines on average) of BCVA in both groups except one 11-year-old girl in the control group(P<0.05). But no significant difference in BCVA improvement of the amblyopic eye between the two groups was found(P=0.725), and amblyopia resolved(BCVA of 0.1 log MAR or better or within 1 log MAR line of the fellow eye) for 13(46.4%) participants in both groups. The number of patients with improvement of stereoacuity was 25 and 13 in the NBPL group and control group(P=0.041), respectively, and a significant difference exists in the distribution of stereopsis at 3 mo between the two groups(P=0.015). Besides, in patients with measurable stereopsis improvement degree and space for improvement in the two groups, the NBPL group also achieved better stereoscopic improvement than the control group(10/11 vs 4/11, P<0.05).CONCLUSION:The NBPL system has a significant effect on the improvement of BCVA and stereoacuity of amblyopia children and is better than traditional training in terms of stereoacuity improvement. Perceptual learning visual training may play a more important role in the treatment of amblyopia in the future.

Numerical simulation of fracture propagation in Russia carbonate reservoirs during refracturing

Refracturing treatment is often performed on Russian carbonate reservoirs because of the quick production decline of reservoirs.The traditional refracturing model assumes that a refracture initiates in the normal direction relative to the initial hydro-fracture.This assumption is inconsistent with oilfield measurements of refracture propagation trajectories.Indeed,the existing model is not based on an indepth understanding of initiation and propagation mechanisms of the second hydraulic fractures during refracturing.In this study,we use the extended finite element method to investigate refracture propagation paths at different initiation angles.Both the enriched function approach and phantom mode technique are incorporated into the refracturing model,thereby ensuring that the refracture can freely extend on the structured mesh without any refinement near the crack tips.Key factors including production time,stress anisotropy and initiation angle,and the propped mechanical effect are analyzed in detail.This study provides new insight into the mechanism of refracture propagation in unconventional reservoirs.