孔源性视网膜脱离术后黄斑裂孔形成的原因分析

目的　探讨孔源性视网膜脱离术后黄斑裂孔形成的原因。方法　回顾性分析2017年10月至2019年12月武汉大学人民医院东院眼科所有孔源性视网膜脱离手术患者的临床资料,筛选术后发生黄斑裂孔的患者,结合光学相干断层扫描（OCT）检查结果分析黄斑裂孔形成的原因。结果　本研究共纳入孔源性视网膜脱离手术患者409例（423眼）,其中行玻璃体切割术者341眼,行巩膜扣带术者78眼,行巩膜环扎术者4眼。回顾性分析发现,423眼视网膜脱离术后共有3眼患者发生黄斑裂孔,发生率为0.71%;其中2眼为玻璃体切割术后发生,裂孔出现时间分别为术后第21天和第30天,发生率为0.59%;1眼为巩膜扣带术后发生,发生时间为术后第5天,发生率为1.28%。所有黄斑裂孔患者均行玻璃体切割联合内界膜剥除术,术后患者黄斑裂孔均愈合,视力均较术前提高。结论　孔源性视网膜脱离术后出现黄斑裂孔极其少见,除与视网膜前膜相关外,还与黄斑区视网膜脱离、黄斑区残留玻璃体皮质牵拉和气泡对黄斑区的牵拉有关。     

三维OCT分析累及黄斑的视网膜脱离巩膜扣带术后黄斑微结构与视力的关系

目的:探讨波及黄斑区的孔源性视网膜脱离(RRD)行巩膜扣带手术前后黄斑区三维光学相干断层扫描图像(3D-OCT)特征,分析其与视力的相关性。方法:回顾性系列病例,30例30眼波及黄斑区的RRD行巩膜扣带术治疗的临床资料,在术后2d,2wk,1、3、6mo随诊时双眼均行3D-OCT检查,观察椭圆体带(EZ)、外界膜(ELM)、黄斑区视网膜下液高度(SRFH)、黄斑中心凹视网膜厚度(CRT)的变化,分析其与术后最佳矫正视力(BCVA)的关系。结果:术前,术后2d,2wk,1、3、6mo SRFH、CRT、BCVA均有差异(P<0.01),术后SRFH、CRT都有不同程度降低,术后BCVA都有不同程度升高,组内两两对比:除SRFH(2wk vs 1mo,P>0.05)、CRT(2d vs 2wk,P>0.05)、BCVA(2d vs术前,2wk vs术前,P>0.05)无统计学意义外,其余各项间的比较均有统计学意义(P<0.05)。EZ、ELM形态可分为:A:EZ和ELM均连续(EZ+ELM+),9眼;B:EZ断裂和ELM连续(EZ-ELM+),7眼;C:EZ连续和ELM断裂:EZ+ELM-,6眼;D:EZ和ELM均断裂(EZ-ELM-),8眼,术后6mo上述4种类型的BCVA分别为0.15±0.04、0.50±0.06、0.54±0.05、0.59±0.09(F=87.210,P<0.05),两两比较:除C vs B和C vs D差异无统计学意义(P>0.05)外,其余各组间的比较差异均有统计学意义(P<0.05)。术后2d的SRF发生率为87%,术后6mo仍有46.6%患者存在持续性SRF。术后CRT与术后SRFH具有正相关关系。结论:巩膜扣带术后黄斑微结构呈动态改变,SRF影响可能表现为BCVA延迟恢复,随着SRF缓慢吸收,CRT逐渐降低,BCVA逐渐升高;ELM或EZ连续提示有较好的BCVA,而ELM断裂可能提示视觉质量更差。     

丝裂霉素C联合巩膜瓣可移动缝线治疗原发性青光眼的临床效果

目的：探讨丝裂霉素C联合巩膜瓣可移动缝线治疗原发性青光眼的临床效果。方法按照手术方式不同将本院收治的120例原发性青光眼患者分为常规组40例、丝裂霉素C组40例和缝线组40例,常规组给予常规小梁切除术治疗,丝裂霉素C组术中应用丝裂霉素C的小梁切除术治疗,缝线组术中联合使用丝裂霉素C＋巩膜瓣可移动缝线小梁切除术治疗,比较3组患者术前、术后第3天、术后1周、术后1个月、术后3个月和术后6个月的眼压变化,术后半年滤过泡情况、术后早期前房深度以及并发症发生情况。结果3组患者术后眼压均显著下降,与术前比较,差异有统计学意义（P〈0.05）;丝裂霉素C组和缝线组患者术后不同时间眼压均显著低于常规组,差异有统计学意义（P〈0.05）;丝裂霉素C组和缝线组患者功能性滤泡形成率均显著高于常规组,差异有统计学意义（P〈0.05）;丝裂霉素C组患者术后早期Ⅰ、Ⅱ度浅前房发生率均显著高于常规组,差异有统计学意义（P〈0.05）;缝线组患者术后早期Ⅰ、Ⅱ度浅前房发生率均显著低于丝裂霉素C组,差异有统计学意义（P〈0.05）;3组均未出现角膜损伤、结膜瓣漏、黄斑水肿、眼内炎、恶性青光眼等并发症。丝裂霉素C组患者正常前房率显著低于常规组和缝线组,差异有统计学意义（P〈0.05）。结论原发性青光眼术中丝裂霉素C联合巩膜瓣可移动缝线能显著提高手术的成功率,改善眼压,合理控制缝线的拆除数目及时间,临床应用和推广价值较高。     

Structural Analysis of Composite Conical Convex-Concave Plate (CCCP) Using VAM-Based Equivalent Model

Compared with the ordinary foundation plate, the composite conical convex-concave plate (CCCP) has obvious anisotropic characteristics, and there is less research on the relationship between its mechanical properties and structural parameters. In this article, a numerical model for the equivalent stiffness of a typical unit cell with conical convex is established by using the variational asymptotic method. Then, the 3D finite element model (3D-FEM) of CCCP is transformed into 2D equivalent plate model (2D-EPM) with the effective plate properties obtained from the constitutive analysis of unit cell. The accuracy of 2D-EPM is verified by comparing with the displacement, natural frequencies, and buckling results from 3D-FEM under different boundary conditions. Then, the influence of geometric parameters and layup configurations on the effective performances of CCCP are investigated. Finally, the buckling loads and natural frequencies of bidirectional CCCP are compared with those of CCCP by using the present model. The present model is particularly useful in the early design stage of CCCP where many design trade-offs need to be made over a vast design space in terms of material selection, ply angles, and geometric parameters.     

Effect of candesartan on the expression of sclera-choroidal intercellular adhesion molecule-1 in hypercholesterolemic models

OBJECTIVE:

To evaluate the effect of blocking the angiotensin II AT-1 receptor by the systemic administration of candesartan on the expression of intercellular adhesion molecule-1 in the sclera and choroid of hypercholesterolemic rabbits.

METHODS:

New Zealand rabbits were divided into 3 groups, as follows: GI, which was fed a rabbit standard diet; GII, which was fed a hypercholesterolemic diet; and GIII, which received hypercholesterolemic diet plus candesartan. Samples of the rabbits'' sclera and choroid were then studied by hematoxylin-eosin staining and histomorphometric and immunohistochemical analyses for intercellular adhesion molecule-1 expression.

RESULTS:

Histological analysis of hematoxylin- and eosin-stained sclera and choroid revealed that macrophages were rarely present in GI, and GII had significantly increased macrophage numbers compared to GIII. Moreover, in GII, the sclera and choroid morphometry showed a significant increase in thickness in comparison to GI and GIII. GIII presented a significant increase in thickness in relation to GI. Sclera and choroid immunohistochemical analysis for intercellular adhesion molecule-1 expression revealed a significant increase in immunoreactivity in GII in relation to GI and GIII. GIII showed a significant increase in immunoreactivity in relation to GI.

CONCLUSION:

Candesartan reduced the expression of intercellular adhesion molecule-1 and consequently macrophage accumulation in the sclera and choroid of hypercholesterolemic rabbits.     

旋律音调疗法联合拮抗肌推拿对脑出血术后偏瘫患者躯体屈曲痉挛和运动功能的影响

目的探讨旋律音调疗法联合拮抗肌推拿对脑出血术后偏瘫患者的躯体屈曲痉挛和运动功能的影响。方法采用整群抽样法,选取本院2017年6月至2018年12月收治的87例脑出血术后偏瘫患者为研究对象,将其随机分为研究组44例和对照组43例,对照组实施常规护理,研究组实施旋律音调疗法联合拮抗肌推拿护理。干预后6个月,比较两组接受躯体屈曲痉挛和运动功能。结果干预前,研究组躯体屈曲痉挛分级、肢体运动功能评分比较差异无统计学意义(P>0.05);干预后,研究组躯体屈曲痉挛分级低于对照组、肢体运动功能评分高于对照组(P<0.05)。结论脑出血术后偏瘫应用旋律音调疗法联合拮抗肌推拿护理,可有效改善躯体屈曲痉挛,恢复运动功能,具有推广价值。     

From the Cover: The macroscopic delamination of thin films from elastic substrates

The wrinkling and delamination of stiff thin films adhered to a polymer substrate have important applications in “flexible electronics.” The resulting periodic structures, when used for circuitry, have remarkable mechanical properties because stretching or twisting of the substrate is mostly accommodated through bending of the film, which minimizes fatigue or fracture. To date, applications in this context have used substrate patterning to create an anisotropic substrate-film adhesion energy, thereby producing a controlled array of delamination “blisters.” However, even in the absence of such patterning, blisters appear spontaneously, with a characteristic size. Here, we perform well-controlled experiments at macroscopic scales to study what sets the dimensions of these blisters in terms of the material properties and explain our results by using a combination of scaling and analytical methods. Besides pointing to a method for determining the interfacial toughness, our analysis suggests a number of design guidelines for the thin films used in flexible electronic applications. Crucially, we show that, to avoid the possibility that delamination may cause fatigue damage, the thin film thickness must be greater than a critical value, which we determine.     

Mechanics of wrinkle formation: micromechanical analysis of skin deformation during wrinkle formation in ultraviolet‐irradiated mice

Background/purpose: The mechanical aspects of wrinkle formation were studied in the dorsal skin of hairless mice. Methods: Wrinkles were induced by irradiating with ultraviolet (UV) B for 10 weeks, while observing skin deformation during wrinkle formation. Changes in skin dimensions were also observed during the specimen excision process. Wrinkle depth and interval were measured before and after removal of the cutaneous muscle layer. Local deformation of wrinkled skin during uniaxial stretch was also measured. Changes in curvature of skin specimens upon muscle layer removal were then observed to determine the force balance in skin layers. Results: The skin showed spontaneous contraction in response to UV irradiation. Wrinkled skin showed a marked decrease in the wrinkle depth and a slight increase in wrinkle interval following muscle layer removal, a peculiar mechanical response that cannot be explained by homogeneous deformation of the skin. This response was due to compressive deformations of dermal tissue caused by the muscle layer and concentrated at valleys of the wrinkles. Curvature measurements indicated that the muscle layer compressed the dermal tissue predominantly in the craniocaudal direction. Morphological observations showed that the wrinkles coincided with rows of pores and sulci cutis, where the structural stiffness of the horny layer was relatively low. The horny layer showed significant thickening. Conclusion: Taken together, we propose the following hypothetical mechanisms of wrinkle formation during UV irradiation: spontaneous contraction of the dermis while maintaining or increasing the epidermal area induces buckling of the epidermis into the dermis at mechanically weak lines, namely, the rows of pores and sulci cutis, and buckling may be amplified by the axial compression of the dermis by the muscle layer.     

不同手术方式对硅油充填术后早期并发症的影响

目的:探讨不同手术方式对无晶状体眼硅油充填术后早期并发症的影响。方法:回顾性分析在我院进行玻璃体视网膜手术的120例患者的临床资料,根据术中是否行巩膜扣带术及巩膜扣带术先后的不同,随机分为3组,每组40眼。A组:单纯硅油充填组;B组:术前预置环扎带+硅油充填组;C组:硅油充填后再进行外加压组,术后2wk内对各组硅油并发症进行观察。结果:术后A,B,C组高眼压的发病率分别为17.5%,12.5%,52.5%,硅油溢入前房的发病率分别7.5%,10.0%,30.0%。C组与其他两组比较差异有显著性意义(P<0.05)。D组与E组进行比较差异有显著统计学意义,χ2=7.505,P<0.01。结论:硅油充填术后早期并发症与手术方式密切相关,适当改进手术技巧,能降低硅油充填术后并发症的发生率。     

Anatomical retinal reattachment after scleral buckling with and without retinopexy: a pilot study

Purpose: To compare the anatomical results of scleral buckling with and without retinopexy and to assess the effect of retinopexy on the scleral buckling outcome. Methods: This randomized clinical trial was performed on 55 patients. Twenty‐two eyes were treated with scleral buckling (segmental or encircling) with or without drainage of subretinal fluid without any type of retinopexy (group 1); 33 patients received transscleral retinal cryopexy around retinal break(s) in addition to the former procedure. The two groups were matched regarding age, sex, myopia, aphakia, stage of proliferative vitroretinopathy (PVR) and number, type and location of the break(s). Results: In the non‐retinopexy group, 19 patients (86%) had complete retinal reattachment and one patient had partial reattachment after 34–48 months of follow‐up. One patient did not develop attachment because of missed break out of the buckle, and one had no attachment at all because of PVR. Overall success rate was 91% (20 of 22) in this group. In the retinal cryopexy group, 26 patients (79%) had complete retinal reattachment and two had partial reattachment during 35–56 months of follow‐up. In two patients, no attachment was achieved because of missed break out of the buckle; three patients developed redetachment after 1 and 3 months because of PVR. Overall success rate was 85% (28 of 33). The anatomical results in these two groups were the same statistically. Conclusion: With the permanent scleral buckling technique, retinal cryopexy adds no benefit to the success rate of anatomical retinal reattachment.