Limited benefit of CT scans in tuberculosis contact tracing

ObjectiveThe detection of abnormal findings on computed tomography (CT) scans of tuberculosis contacts combined with normal plain radiographs contributes to the early detection of tuberculosis. However, the benefit of the early detection of abnormalities for the prevention of active tuberculosis during follow-up requires evaluation.MethodWe conducted retrospective comparison of the existence of CT scans of tuberculosis contacts without findings of active tuberculosis on plain radiographs at a hospital in Japan. Results: Among 243 contacts without CT scans, five developed tuberculosis during follow-up. Among 229 contacts with CT scans, 24 were judged as targets of multi-drug therapy since their CT findings were suggestive of active tuberculosis at the time of the CT screening. Among 205 contacts judged as having latent tuberculous infection with CT screening, three developed tuberculosis diseases during follow-up. Conclusion: CT scans detected abnormal findings among contacts without abnormalities of plain radiographs but there were some contacts that developed tuberculosis diseases among those with contact investigation including CT scan. The value of CT is equivocal considering the balance of true treatment, overtreatment and harm of radiation.     

Is the spectacle lens jack‐in‐the‐box phenomenon really due to the lenses?

The calculation of the extent of the ring scotoma around positive lenses, as conventionally taught to students of clinical optics, indicates that the scotoma is of a significant size. Using knife-edge lenses this study shows that the calculations are invalid due to the finite size of the eye's entrance pupil and in many instances the scotoma is shown not to exist. The effect noticed in clinical practice is probably largely due to the frame and the edging techniques used which add to the refractive scotoma which is present with high powered lenses, large apertures and/or small pupil sizes.     

白内障超声乳化吸出及囊袋内人工晶体植入术

为观察和评价超声乳化白内障吸出术的临床效果、特点、并发病及防治措施，对４１　眼白内障施行超声乳化吸出术及小切口（６ｍｍ）囊袋内人工晶体植入术，并以同期的白内障患者４１眼行现代囊外摘除及后房型人工晶体植入做对照。结果：术后６个月，视力≥１．０者占４３．９％＞０．８者占７０．７≥０．５者占９２．７％，均明显高于对照组（Ｐ＜０．００１），术后平均散光为１．０４±０．８１，１，低于对照组（Ｐ＜０．０１）。白内障超声乳化吸出并囊袋内人工晶体植入术的复明效果优于囊外摘除并后房型人工晶体植入术。     

La dimension de contact et les troubles esthéticophysiognomiques

Dimension of contact is the very moment when meeting with someone. The limits can be precisely defined as an aesthetic moment, i.e. the very moment when someone appears. That is an experience of one's expressivity. One can usually go through this ephemeral moment to reach simple self-continuity. Pathologies of contact may be described at different levels: neurosis, pathological personalities and psychosis.     

Grading static versus dynamic images of contact lens complications

Background: This study was conducted to investigate grading performance when estimating the severity of static versus dynamic images of contact lens‐related ocular pathology. Methods: Thirty‐eight subjects used the Efron Grading Scales for Contact Lens Complications to grade the severity of ocular pathological changes depicted in static and dynamic (movie clip) computer‐displayed images of each of the following contact lens complications: bulbar conjunctival redness, limbal redness, papillary conjunctivitis, corneal staining, corneal infiltrates and meibomian gland dysfunction. The viewing of static and dynamic images was separated by seven weeks. Results: Grades assigned to dynamic images were 0.6 and 0.7 grading scale units higher than those assigned to static images for limbal redness and papillary conjunctivitis, respectively (p < 0.0001 for both). No difference was observed for the other four complications. There was an apparent trend for grading variability to be reduced (that is, observers grading in closer agreement) when grading dynamic versus static images. Conclusions: Absolute grades based on an assessment of signs of pathology represented in static images may, in some instances, underestimate the true severity of the condition.     

角膜接触镜对泪膜流动和破裂时间的影响

观察５０例长期配戴亲水性角膜接触镜者戴镜前后ＳｃｈｉｒｍｅｒＩ试验和泪膜破裂时间（ＢＵＴ）的变化。结果表明，戴接触镜后ＢＵＴ缩短，ＳｃｈｉｒｍｅｒＩ下降，双眼ＢＵＴ与ＳｃｈｉｒｍｅｒＩ之间无相关性。讨论了引起泪膜流动和ＢＵＴ改变的机制。     

The spherical aberration of aphakic eyes corrected with intra-ocular lenses

The spherical aberration of eyes corrected with intra-ocular lenses is investigated using a model eye with realistic levels of corneal asphericity. The results indicate that the aberration is intermediate between that of paraxial schematic eyes and real eyes. By using standard optical aberration theory, it is shown that for a plano-convex lens with the curved surface facing the cornea, the aberration is similar to that of normal phakic eyes and therefore probably too low to be of any clinical significance. However, for other lens orientations or designs, the level of aberration is usually higher and may lead to a refractive error varying with pupil size and a loss of acuity with large pupil diameters.     

塑料镜片材料的发展动向

概述光学塑料的基本材料，讨论塑料镜片材料的主要品种及其应用，并着重分析影响塑料镜片材料性能的主要因素及其发展趋势。