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31.
32.
目的观察颞上视网膜分支静脉阻塞(branch retinal vein occlusion,BRVO)合并黄斑水肿的频域光学相干断层扫描(spectral domain-optical coherence tomography,SD-OCT)特征,分析视野改变特点。方法回顾性研究。随机选取2019年2月至11月于承德医学院附属医院眼科确诊为BRVO合并黄斑水肿患者34例(34眼)作为BRVO组,同期健康人16人(29眼)作为正常对照组。两组均行最佳矫正视力、裂隙灯显微镜、眼压、间接检眼镜、荧光素眼底血管造影(fundus fluorescein angiograph,FFA)、SD-OCT、自动静态视野计检查。比较两组采用SD-OCT测量的黄斑各分区视网膜厚度、视野平均光敏度(mean sensitivity,MS)及视野平均缺损(mean defect,MD)。结果BRVO组中,黄斑区视网膜可呈海绵样弥漫型视网膜增厚、黄斑囊样水肿、浆液性视网膜脱离及混合型(前三种模式特征皆有)等多种形态表现。BRVO组黄斑中心凹,黄斑中心内外环的颞侧、上方、鼻侧、下方,共9个区域的视网膜厚度分别为(398.09±106.69)μm、(425.06±99.09)μm、(467.18±89.36)μm、(402.53±94.27)μm、(349.47±61.61)μm、(367.44±98.67)μm、(440.88±79.37)μm、(343.32±47.43)μm、(292.91±40.66)μm,正常对照组相应部位分别为(234.21±12.16)μm、(303.21±14.47)μm、(317.90±13.81)μm、(316.59±15.32)μm、(316.76±13.00)μm、(269.48±14.19)μm、(286.86±11.79)μm、(294.76±12.98)μm、(268.76±13.71)μm,两组间比较差异均有统计学意义(均为P<0.05)。BRVO组、正常对照组下方视野MS分别为(18.71±5.47)dB、(27.17±1.18)dB,差异有统计学意义(P<0.05)。黄斑中心内环上半侧、黄斑中心外环上半侧视网膜厚度与下方视野MD均无相关性(均为P>0.05)。结论BRVO合并的黄斑水肿呈现形态多种、分布广泛的特征,同时具有下方视野损害的特点。  相似文献   
33.
The purpose of this study was to assess the pre- and postoperative position and dimensions of the inferior alveolar canal (IAC) following sagittal split osteotomy (SSO) and identify any association with postoperative neurosensory deficit (NSD) at 1 year. This retrospective cohort study enrolled consecutive patients who had SSO performed to correct skeletal malocclusion. The pre- and postoperative cone beam computed tomography data were superimposed to visualize differences in IAC position and dimensions. Subjective and objective neurosensory tests were used to determine NSD in the inferior alveolar nerve distribution. A total of 20 subjects were included. The preoperative distance from the lateral cortex of the IAC to the inner aspect of the lateral cortex of the mandible was significantly greater in sides with NSD when compared to sides without NSD (P = 0.01). A significantly greater reduction in the postoperative distance measurement was seen in sides with NSD when compared to sides without NSD (P = 0.01). The magnitude of mandibular movement was significantly increased in sides with NSD (P = 0.02). The preoperative location of the IAC, as well as certain changes in the mediolateral and vertical positions as a result of SSO, are risk factors for postoperative NSD.  相似文献   
34.
目的 总结小脑前下动脉瘤的临床和影像学特点,以及手术夹闭与介入治疗两种方法的治疗效果。 方法 回顾性分析首都医科大学附属北京天坛医院神经外科2012年1月-2019年12月收治的小脑前 下动脉瘤患者的基线信息、临床表现、动脉瘤特点、治疗方式和治疗效果。 结果 共收治11例小脑前下动脉瘤患者,其中显微外科手术夹闭动脉瘤5例,治愈率100%,术后2例 (40%)出现不完全性失语和手术侧面瘫,随访均无复发;介入治疗6例,5例(83.3%)完全栓塞动脉 瘤,其中2例(33.3%)闭塞动脉瘤远端载瘤动脉,1例(16.7%)栓塞治疗失败,术后1例(16.7%)出现 记忆力下降,1例(16.7%)出院1个月后动脉瘤破裂,并最终死亡。 结论 对于小脑前下动脉瘤,积极干预对于挽救患者生命意义重大,开颅手术夹闭和介入治疗都是 可选的治疗方式,两者均效果确切。  相似文献   
35.
36.
ABSTRACT

Purpose: The purpose of this study is to describe clinical features and visual outcomes of Japanese patients with posterior scleritis.

Methods: Clinical records of 10 patients (13 eyes) presenting between 2006 and 2016 were retrospectively reviewed.

Results: The mean age was 50.1 ± 20.8 years; 50% were women, and three patients had bilateral disease. Associated anterior scleritis (11 eyes, 85%) and serous retinal detachment (8 eyes, 62%) were common at presentation. Treatment consisted of corticosteroids (all patients) and immunosuppressive agents (seven patients). The mean subfoveal choroidal thickness was significantly reduced over follow-up [611 μm at baseline, 298 μm (p < 0.01) at 1 month, and 238 μm (p < 0.01) at 1 year]. Recurrent inflammation was observed in six patients. A best-corrected visual acuity of 0.8 or better was achieved in all 13 eyes at 3 years and 71% of eyes at 5 years.

Conclusion: Although 60% of patients with posterior scleritis had recurrence, visual outcomes were favorable.  相似文献   
37.
The role of microglia in retinal inflammation is still ambiguous. Branch retinal vein occlusion initiates an inflammatory response whereby resident microglia cells are activated. They trigger infiltration of neutrophils that exacerbate blood–retina barrier damage, regulate postischemic inflammation and irreversible loss of neuroretina. Suppression of microglia-mediated inflammation might bear potential for mitigating functional impairment after retinal vein occlusion (RVO). To test this hypothesis, we depleted microglia by PLX5622 (a selective tyrosine kinase inhibitor that targets the colony-stimulating factor-1 receptor) in fractalkine receptor reporter mice (Cx3cr1gfp/+) subjected to various regimens of PLX5622 treatment and experimental RVO. Effectiveness of microglia suppression and retinal outcomes including retinal thickness as well as ganglion cell survival were compared to a control group of mice with experimental vein occlusion only. PLX5622 caused dramatic suppression of microglia. Despite vein occlusion, reappearance of green fluorescent protein positive cells was strongly impeded with continuous PLX5622 treatment and significantly delayed after its cessation. In depleted mice, retinal proinflammatory cytokine signaling was diminished and retinal ganglion cell survival improved by almost 50% compared to nondepleted animals 3 weeks after vein occlusion. Optical coherence tomography suggested delayed retinal degeneration in depleted mice. In summary, findings indicate that suppression of cells bearing the colony-stimulating factor-1 receptor, mainly microglia and monocytes, mitigates ischemic damage and salvages retinal ganglion cells. Blood–retina barrier breakdown seems central in the disease mechanism, and complex interactions between different cell types composing the blood–retina barrier as well as sustained hypoxia might explain why the protective effect was only partial.  相似文献   
38.
The auditory midbrain is the location in which neurons represent binaural acoustic information necessary for sound localization. The external nucleus of the midbrain inferior colliculus (IC) of the barn owl is a classic example of an auditory space map, but it is unknown to what extent the principles underlying its formation generalize to other, less specialized animals. We characterized the spiking responses of 139 auditory neurons in the IC of the chicken (Gallus gallus) in vivo, focusing on their sensitivities to the binaural localization cues of interaural time (ITD) and level (ILD) differences. Most units were frequency‐selective, with best frequencies distributed unevenly into low‐frequency and high‐frequency (> 2 kHz) clusters. Many units showed sensitivity to either ITD (65%) or ILD (66%) and nearly half to both (47%). ITD selectivity was disproportionately more common among low‐frequency units, while ILD‐only selective units were predominantly tuned to high frequencies. ILD sensitivities were diverse, and we thus developed a decision tree defining five types. One rare type with a bell‐like ILD tuning was also selective for ITD but typically not frequency‐selective, and thus matched the characteristics of neurons in the auditory space map of the barn owl. Our results suggest that generalist birds such as the chicken show a prominent representation of ITD and ILD cues in the IC, providing complementary information for sound localization, according to the duplex theory. A broadband response type narrowly selective for both ITD and ILD may form the basis for a representation of auditory space.  相似文献   
39.
Purpose: To evaluate retinal nerve fiber layer thickness (RNFLT), ganglion cell layer thickness (GCLT), subfoveal choroidal thickness (SFCT), and central retinal thickness (CRT) in asthmatic children who were under inhaled corticosteroid treatment by using Swept-Source Optical Coherence Tomography (SS-OCT).

Material and methods: Fifty-three children were prospectively analyzed in the study. Group 1 included 31 asthmatic children and group 2 included 22 healthy children. Asthmatic children received a dose 250?μg daily of inhaled fluticasone propionate (Flexotide, GlaxoSmithKline, Middlesex, UK). Allergy parameters including, exposure to smoke, eosinophil count, percentage of eosinophils, immunoglobuline (Ig) E levels, number of asthma attacks, number of sensitivity to allergens and follow-up time were recorded. The RNFLT, GCLT, SFCT, and CRT were analyzed with SS-OCT and the data were compared between the groups.

Results: There were 13 girls (41.9%) and 18 boys (58.1%) in group 1 and 13 girls (59.1%) and 9 boys (40.9%) in group 2 (p?=?0.22). The mean age was 9.3?±?2.2 years in group 1 and 9.9?±?1.5 years in group 2 (p?=?0.08). The mean CRT (239.26?±?34.56 µm versus 226.82?±?26.23 µm, p?=?0.22) and mean SFCT (273.97?±?40.95 µm versus 280.41?±?32.78 µm, p?=?0.54) did not significantly differ between the groups. The superior, inferior, and average RNFLT were significantly lower in group 1 than group 2 (p?p?p?Conclusions: The SS-OCT revealed that asthmatic children under inhaled corticosteroid treatment have lower RNFLT than healthy subjects.  相似文献   
40.
A 55 year-old female patient with unilateral Acute Retinal Necrosis (ARN) developed macular oedema (MO) after the resolution of her necrosis. The macular oedema (MO) was managed and controlled for four years with intravitreal anti-VEGF injections. Anti-VEGF therapy could be useful for the treatment of MO secondary to ARN, the same as for treating MO resulting from panuveitis, where its efficacy has been already demonstrated.  相似文献   
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