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1.
Tears are secreted from the lacrimal gland (LG), a dysfunction in which induces dry eye, resulting in ocular discomfort and visual impairment. Honey bee products are used as a nutritional source in daily life and medicine; however, little is known about their effects on dry eye. The aim of the present study was to investigate the effects of honey bee products on tear secretion capacity in dry eye. We selected raw honey, propolis, royal jelly (RJ), pollen, or larva from commercially available honey bee products. Tear secretion capacity was evaluated following the oral administration of each honey bee product in a rat blink-suppressed dry eye model. Changes in tear secretion, LG ATP content, and LG mitochondrial levels were measured. RJ restored the tear secretion capacity and decrease in LG ATP content and mitochondrial levels to the largest extent. Royal jelly can be used as a preventative intervention for dry eye by managing tear secretion capacity in the LG.  相似文献   

2.
Constructing an internal representation of the world from successive visual fixations, i.e. separated by saccadic eye movements, is known as trans-saccadic perception. Research on trans-saccadic perception (TSP) has been traditionally aimed at resolving the problems of memory capacity and visual integration across saccades. In this paper, we review this literature on TSP with a focus on research showing that egocentric measures of the saccadic eye movement can be used to integrate simple object features across saccades, and that the memory capacity for items retained across saccades, like visual working memory, is restricted to about three to four items. We also review recent transcranial magnetic stimulation experiments which suggest that the right parietal eye field and frontal eye fields play a key functional role in spatial updating of objects in TSP. We conclude by speculating on possible cortical mechanisms for governing egocentric spatial updating of multiple objects in TSP.  相似文献   

3.
摘要 目的:探讨视觉功能训练联合托吡卡胺滴眼液在治疗假性近视中的临床疗效。方法:选取中国人民解放军陆军特色医学中心眼科和重庆佑佑宝贝妇儿医院眼科2019年2月至2019年8月收治的400例假性近视患儿作为研究对象,将其随机分为对照组和观察组(n=200)。对照组给予滴眼液缓解眼疲劳治疗,观察组则采用视觉功能训练联合托吡卡胺滴眼液治疗。比较两组患儿治疗前及治疗2个月、6个月后裸眼视力、眼轴长度、屈光度、正相对调节量和视疲劳评分的变化。结果:治疗2个月和6个月后,观察组患儿裸眼视力分别为(0.75±0.05)和(0.81±0.04),较对照组显著上升(P<0.05);屈光度分别为(+0.05±0.50)和(+0.06±0.48),明显高于对照组(P<0.05);正相对调节量检测结果依次是(-1.98±0.07)和(-2.51±0.24),较对照组明显增加(P<0.05)。两组患儿视觉感知双眼视功能均有明显改善,其中观察组视觉功能恢复显著高于对照组(P<0.05)。视疲劳调查显示观察组患儿视疲劳评分分别为(6.90±0.89)分和(3.91±0.89)分,显著低于对照组(P<0.05)。结论:视觉功能训练联合托吡卡胺滴眼液治疗能有效提高患儿裸眼视力、改善屈光度、正相对调节量和视觉感知功能,从而减少视疲劳,预防近视。  相似文献   

4.
The frontal eye fields (FEF) in rhesus monkeys have been implicated in visual short-term memory (VSTM) as well as control of visual attention. Here we examined the importance of the area in the VSTM capacity and the relationship between VSTM and attention, using the chemical inactivation technique and multi-target saccade tasks with or without the need of target-location memory. During FEF inactivation, serial saccades to targets defined by color contrast were unaffected, but saccades relying on short-term memory were impaired when the target count was at the capacity limit of VSTM. The memory impairment was specific to the FEF-coded retinotopic locations, and subject to competition among targets distributed across visual fields. These results together suggest that the FEF plays a crucial role during the entry of information into VSTM, by enabling attention deployment on targets to be remembered. In this view, the memory capacity results from the limited availability of attentional resources provided by FEF: The FEF can concurrently maintain only a limited number of activations to register the targets into memory. When lesions render part of the area unavailable for activation, the number would decrease, further reducing the capacity of VSTM.  相似文献   

5.
目的 观察深板层角膜移植术(deep lamellar keratoplasty,DLKP)和穿透性角膜移植术(penetrating keratoplasty,PKP)治疗真菌性角膜炎的临床疗效.方法 回顾44例(44眼)临床确诊为真菌性角膜炎的患者,根据共焦激光显微镜检查是否累及角膜内皮分别行DLKP 28例(28眼)或PKP 16例(16眼).术后随访6~24个月,观察术后真菌复发情况以及拆线后两周视力和角膜地形图散光.结果 术后角膜病理切片检查均检出真菌.术后DLKP组有1例、PKP组有3例出现排斥反应,经抗排斥治疗后均好转.拆线后两周最佳矫正视力DLKP组为0.59×0.04,PKP组为0.41 ×0.05,两组间相比较差异具有统计学意义(t =2.577,P =0.01);角膜地形图散光DLKP组为(2.0 ×0.17) D;PKP组为(2.9×0.30)D,两组间相比较差异具有统计学意义(t =0.088,P=0.016).结论 激光共焦显微镜检查对于手术方式的选择提供了良好的客观依据.两种手术方式治疗真菌性角膜炎均有良好的疗效,DLKP术后视觉疗效优于PKP.  相似文献   

6.
There are several methods for presbyopia treatment. Refractive lens exchange (RLE) followed by multifocal intraocular lens (MFIOL) implantation enables high rate of spectacle independence but have some visual disturbances. Laser in Situ Keratomileusis (LASIK) monovision gives patient ability to have good distant vision with dominant eye and good near vision with nondominant eye. In this prospective randomized study we wanted to compare clinical outcomes in patients who underwent either of the mentioned procedures. The first group included 50 patients (N = 100 eyes) who underwent RLE with MFIOL implantation and the second group included 50 patients (N = 100 eyes) who underwent LASIK monovision as presbyopia treatment. Uncorrected distant, near and intermediate visual acuity, patient's subjective satisfaction and visual disturbances were measured. Follow up was 6 months. Patients in RLE group had better near uncorrected visual acuity (UCVA) and patients in LASIK monovision group had better distant and intermediate vision. Patients in RLE group reported visual disturbances (halo, glare). Patients satisfaction and spectacle independence was high in both groups. Refractive lens exchange with multifocal intraocular lens implantation and LASIK monovision are effective methods for presbyopia treatment. LASIK monovision with -0.50D - 1.25D of residual dioptry at nondominant eye in patients under 50 years enables good vision at all distances without affecting stereovision. Patient selection and preoperative counseling are key to success.  相似文献   

7.
Secondary chronic open-angle glaucoma associated with pseudoexfoliation (PEX) syndrome accounts for approximately 25% of all glaucomas and represents the most common identifiable cause of glaucoma overall. Selective laser trabeculoplasty (SLT) is effective in reducing intraocular pressure (IOP) in glaucomatous patients and has the advantage of preserving surrounding structures. We report here SLT treatment of a 82 year old female with a secondary developed open-angle pseudoexfoliation glaucoma allergic to all anti glaucoma eye drops especially those which contain bensalconium chloridum as preservative. Since patient was allergic also to methyl-cellulose, we performed SLT with water as a mediator. Patient had PEX syndrome for 10 years, immature cataracts on both eyes, and best corrected visual acuity (BCVA) 0.7 on the right and 0.2 on the left eye. We have monitored intraocular pressure (IOP), the changes in the visual field and optic nerve. Preoperative IOP was 28 mmHg on the right and 30 mmHg on the left eye. The follow up period was 24 months with time points for measured parameters every 3 months. After 18 months IOP remained in the normal values (average 17 mmHg) on the right eye, but on the left eye it increased up to 28 mmHg. SLT re-treatment was carried out on the left eye and the IOP stabilized again on the values between 16-18mmHg. There were no significant change in the visual field and optic nerve configuration before and after SLT (C/D value for right eye: 0.3-0.4; C/D left eye: 0.5). Based on this case report, SLT seems to be very effective treatment for maintaining regular IOP in patient with PEX who is allergic to all types of medications.  相似文献   

8.
Out of 29 patients who presented with failing vision in one eye due to optic nerve or chiasmal compression, compression was initially diagnosed in only five. The errors in diagnosis and lack of ophthalmological follow-up led to delays of up to many years with serious deterioration in acuity before referral for intracranial investigation. The chief causes of error were lack of charting of the visual fields, too ready acceptance of the diagnosis of the neuritis in the absence of essential features, and the infrequent use of skull radiographs.  相似文献   

9.

Background

In this work, we propose the Halo test, a simple visual test based on a freeware software for quantifying and displaying night-vision disturbances perceived by subjects under different experimental conditions, more precisely studying the influence of the alcohol consumption on visual function.

Methods

In the Halo test, viewed on a monitor, the subject's task consists of detecting luminous peripheral stimuli around a central high-luminance stimulus over a dark background. The test, performed by subjects before and after consuming alcoholic drinks, which deteriorate visual performance, evaluates the influence that alcohol consumption exerts on the visual-discrimination capacity under low illumination conditions. Measurements were made monocularly and binocularly. Pupil size was also measured in both conditions (pre/post). Additionally, we used a double-pass device to measure objectively the optical-quality of the eye and corroborate the results from the Halo test.

Results

We found a significant deterioration of the discrimination capacity after alcohol consumption, indicating that the higher the breath-alcohol content, the greater the deterioration of the visual-discrimination capacity. After alcohol intake, the graphical results showed a greater area of undetected peripheral stimuli around the central high-luminance stimulus. An enlargement of the pupil was also observed and the optical quality of the eye was deteriorated after alcohol consumption.

Conclusions

A greater influence of halos and other night-vision disturbances were reported with the Halo test after alcohol consumption. The Halo freeware software constitutes a positive contribution for evaluating nighttime visual performance in clinical applications, such as reported here, but also in patients after refractive surgery (where halos are present) or for monitoring (time course) some ocular pathologies under pharmacological treatment.
  相似文献   

10.
摘要 目的:探讨复明片联合曲伏前列素滴眼液对原发性开角型青光眼(POAG)患者眼部血流动力学和房水促红细胞生成素(EPO)、可溶性CD44(sCD44)的影响。方法:选择2017年4月~2020年11月在本院接受治疗的112例193眼的POAG患者,根据随机数字表法分为对照组(n=56,96眼)和研究组(n=56,97眼),对照组患者接受曲伏前列素滴眼液治疗,研究组接受复明片联合曲伏前列素滴眼液治疗,对比两组疗效、眼部血流动力学和房水EPO、sCD44,视力、视野、眼压,观察治疗期间不良反应发生状况。结果:研究组的临床总有效率高于对照组(P<0.05)。治疗12周后,研究组平均光敏感度(MS)、视力高于对照组,24 h眼压平均值小于对照组(P<0.05)。治疗12周后,研究组舒张末期流速(EDV)、收缩期峰值流速(PSV)高于对照组,血流阻力系数(RI)小于对照组(P<0.05)。治疗12周后,研究组房水EPO、sCD44水平低于对照组(P<0.05)。两组不良反应发生率组间对比无统计学差异(P>0.05)。结论:复明片联合曲伏前列素滴眼液治疗POAG患者,可促进患者视力、视野、眼压改善,可能与调节眼部血流动力学和房水EPO、sCD44水平有关。  相似文献   

11.
Bright light treatment has become an important method of treating depression and circadian rhythm sleep disorders. The efficacy of bright light treatment may be dependent upon the position of the light-source, as it determines the relative illumination in each portion of the visual field. This study compared illumination of upper and middle visual fields to determine whether melatonin suppression is different or equivalent. Thirteen older volunteers received three illumination conditions in counterbalanced orders: 1000 lux in the upper visual field, 1000 lux in the middle visual field, or dim diffuse illumination < 5 lux. A four-choice reaction time task was performed during tests to ensure eye direction and illumination of the intended portion of the visual field. Illumination in the upper and middle visual fields significantly suppressed melatonin compared to < 5 lux (p < 0.001). Melatonin suppression was not significantly different with upper or middle field illumination. These results indicate that bright light treatments placed above the eye level might be as effective as those requiring patients to look directly at the light source. Clinical comparative testing would be valuable. In addition, this study demonstrates that significant suppression of melatonin may be achieved through the use of bright light in healthy older volunteers.  相似文献   

12.
无眼动条件下中文阅读的研究   总被引:4,自引:1,他引:3  
设计了计算机控制的中文阅读材料的不同显示方式,并对各种阅读过程中的徙动波形进行记录和分析。实验结果表明,无眼动的阅读速度较正常有眼动高,分别为853字/分和640字/分。通过固定窗口显示方式和知动窗口显示方式条件下中文阅读的比较,排除了强迫阅读的因素,说明有无眼动是产生阅读速度差异的主要原因;根据以上实验结果,可得出结论,在有眼动的情况下,除了saccade抑制影响阅读和识别外,主要的因素在于高级中枢对位置信号的处理,眼动的驱动控制及运动过程影响了高级中枢对阅读内容和识别内容的解码速率。无眼动阅读的速度主要受到高级中枢解码速率和记忆的影响,而不是周边视觉系统的限制。实验结果还表明,在无眼动的情况下,周边信息对阅读不仅不起帮助作用,反而起到干扰作用。  相似文献   

13.
Endogenous fungal endophthalmitis (EFE) caused by disseminated fusariosis is a rare condition that generally has a poor outcome, even with intensive therapy. Here, we describe a case in which this type of EFE was diagnosed with vitreous sampling and was successfully treated with 25-gauge vitrectomy and antifungals, including liposomal amphotericin B and voriconazole. A 16-year-old male patient undergoing treatment for acute myeloid leukemia complained of eye pain and blurred vision in his right eye. Treatment was initiated for a vitreous opacity, possibly associated with herpetic retinitis, but the patient worsened and he was referred to us. Right-eye visual acuity was limited to light perception. We suspected endogenous endophthalmitis and performed 25-gauge vitrectomy with antibiotic perfusion of ceftazidime, vancomycin, and voriconazole. Vitreous culturing revealed the presence of Fusarium solani species complex, and enhanced computed tomography revealed disseminated fusariosis lesions in the lung, spleen, and the soft tissue of the left upper arm. The patient received antifungal treatment with liposomal amphotericin B and voriconazole, and these conditions were eliminated. Visual acuity recovered to 20/400 after additional vitrectomy for tractional retinal detachment and was maintained at this level during the 6-month follow-up period. The success of our treatment allowed the capture of optical coherence tomography images of the retina during fusarium-associated endogenous endophthalmitis and the follow-up period. Furthermore, this case showed that immediate vitrectomy for suspected EFE and intensive treatment can lead to a good clinical outcome.  相似文献   

14.
ObjectiveTo investigate the effect of latanoprost on intraocular pressure (IOP), visual acuity and C-reactive protein (CRP) in patients with primary open-angle glaucoma (POAG).MethodsA total of 163 POAG patients (266 eyes) admitted to our hospital from February 2015 to July 2017 were selected and divided into observation group (81 cases, 132 eyes, latanoprost eye drops) and control group (82 cases, 134 eyes, timolol maleate eye drops) according to different treatment plans. The clinical efficacy of the two groups after treatment was evaluated. The IOP, visual acuity and CRP level were compared between the two groups before and after treatment. Then the adverse reactions of the two groups were observed and recorded.ResultsAfter treatment, the total effective rate was 92.59% (75 cases) in the observation group and was 80.49% (66 cases) in the control group, with statistic difference between groups (P < 0.05); The IOP, visual acuity and CRP level between the two groups before treatment showed no statistic difference, the mentioned three indexes of the two groups were significantly improved after treatment, and statistic difference was found before and after treatment (P < 0.05); Moreover, the above three indicators had statistically significant differences between groups after treatment (P < 0.05); The difference of intraocular pressure and visual acuity between the two groups before and after treatment were statistically different (P < 0.05); After treatment, the incidence of adverse reactions in the observation group such as allergy, vomiting, breathlessness and tachycardia were not significantly different from those in the control group (P > 0.05).ConclusionLatanoprost can improve IOP, visual acuity, and CRP levels. It improves eye hemodynamics, and has significant efficacy in treating primary open-angle glaucoma. Also, it has good security.  相似文献   

15.
In a single-blind controlled clinical trial patients with optic neuritis caused by demyelination were given a single retrobulbar injection of triamcinolone. Though the treated group showed a trend towards more rapid recovery of vision than the controls, there was no significant difference in visual acuity, colour vision, or visual fields during the first six months after treatment. We conclude that routine use of corticosteroids is not justified in unilateral optic neuritis when vision in the other eye is good. Shortening the period of visual disability in bilateral disease or unilateral disease when vision in the other eye is poor, however, may be justifiable.  相似文献   

16.
Bright light treatment has become an important method of treating depression and circadian rhythm sleep disorders. The efficacy of bright light treatment may be dependent upon the position of the light-source, as it determines the relative illumination in each portion of the visual field. This study compared illumination of upper and middle visual fields to determine whether melatonin suppression is different or equivalent. Thirteen older volunteers received three illumination conditions in counterbalanced orders: 1000 lux in the upper visual field, 1000 lux in the middle visual field, or dim diffuse illumination <5 lux. A four-choice reaction time task was performed during tests to ensure eye direction and illumination of the intended portion of the visual field. Illumination in the upper and middle visual fields significantly suppressed melatonin compared to <5 lux (p<0.001). Melatonin suppression was not significantly different with upper or middle field illumination. These results indicate that bright light treatments placed above the eye level might be as effective as those requiring patients to look directly at the light source. Clinical comparative testing would be valuable. In addition, this study demonstrates that significant suppression of melatonin may be achieved through the use of bright light in healthy older volunteers.  相似文献   

17.
Eleven euthyroid patients with severe Graves'' eye disease were treated with intravenous methylprednisolone and followed up for six months or more by ophthalmological assessment, orbital computed tomography (CT), photographs, and antibody measurements. Papilloedema resolved in the single patient in whom it was present; visual acuity was abnormal in seven eyes initially and in only one eye after treatment; the intraocular pressure differential, which reflects muscle dysfunction, was initially abnormal in 18 eyes but showed a progressive and distinct improvement; nine patients showed substantial improvement in inflammatory signs. Exophthalmos improved early after treatment, but this improvement was not maintained. Orbital CT showed a pronounced reduction in the bulk of eye muscles after treatment in eight of nine patients. Autoantibodies to the thyroid stimulating hormone receptor declined. Adverse effects were trivial. Thus eight patients showed a clear response to intravenous methylprednisolone as judged by ophthalmic assessment and CT scan. The two patients who showed little response and one who had none all had a long history (more than a year) of ophthalmopathy. Results were better than those with oral steroids and adverse effects less. Treatment of Graves'' eye disease is more likely to be effective if given early; patients should be referred promptly to specialist centres, where treatment with intravenous methylprednisolone should be considered.  相似文献   

18.

Background

Shortly after eye opening, initially disorganized visual cortex circuitry is rapidly refined to form smooth retinotopic maps. This process asymptotes long before adulthood, but it is unknown whether further refinement is possible. Prior work from our lab has shown that the retinotopic map of the non-dominant ipsilateral eye develops faster when the dominant contralateral eye is removed. We examined whether input from the contralateral eye might also limit the ultimate refinement of the ipsilateral eye retinotopic map in adults. In addition, we examined whether the increased refinement involved the recruitment of adjacent cortical area.

Methodology/Principal Findings

By surgically implanting a chronic optical window over visual cortex in mice, we repeatedly measured the degree of retinotopic map refinement using quantitative intrinsic signal optical imaging over four weeks. We removed the contralateral eye and observed that the retinotopic map for the ipsilateral eye was further refined and the maximum magnitude of response increased. However, these changes were not accompanied by an increase in the area of responsive cortex.

Conclusions/Significance

Since the retinotopic map was functionally refined to a greater degree without taking over adjacent cortical area, we conclude that input from the contralateral eye limits the normal refinement of visual cortical circuitry in mice. These findings suggest that the refinement capacity of cortical circuitry is normally saturated.  相似文献   

19.

Background

Vision loss causes major changes in lifestyle and habits that may result in psychological distress and further reduction in the quality of life. Little is known about the magnitude of psychological distress in patients with vision loss and its variation with the normal. The aim of this study is, therefore, to investigate the psychological effects of vision loss and its determinants among Ethiopians.

Methods

A comparative cross-sectional study was conducted on adults attending the Eye clinic of Jimma University Hospital. One hundred fifteen consecutive adults with visual loss at least in one eye and 115 age-and sex-matched controls with normal vision were studied. The psychological distress was measured using standardized Self-Reporting Questionnaire (SRQ-20). Chi-square test and logistic regression were carried out and associations were considered significant at P<0.05.

Results

The overall prevalence of psychological distress was 33.4%. While psychological distress was found in 49.8% of patients who had loss of vision at least in one eye, only 18.3% of the controls had it. In the adjusted analysis, patients with vision loss had 4.6 times higher risk of suffering from psychological distress compared to patients with normal vision (AOR 4.56; 95% CI 2.16-9.62). Moreover, patients with vision loss in both eyes (AOR 4.00; 95% CI 1.453-11.015) and with worse visual acuity in the better eye (AOR 3.66; 95% CI 1.27-10.54) were significantly more likely to have psychological distress than those patients with vision loss in one eye only and good visual acuity in the better eye respectively. The cause of visual loss, pattern of visual loss, duration of visual loss and sociodemographic variables did not influence the likelihood of having psychological distress.

Conclusion

Prevalence of psychological distress was significantly higher in patients with visual loss compared to patients with normal vision. There is a need for integration of psychosocial care into the current medical and surgical treatment of patients with vision loss.  相似文献   

20.
Strepsirrhine and haplorhine primates exhibit highly derived features of the visual system that distinguish them from most other mammals. Comparative data link the evolution of these visual specializations to the sequential acquisition of nocturnal visual predation in the primate stem lineage and diurnal visual predation in the anthropoid stem lineage. However, it is unclear to what extent these shifts in primate visual ecology were accompanied by changes in eye size and shape. Here we investigate the evolution of primate eye morphology using a comparative study of a large sample of mammalian eyes. Our analysis shows that primates differ from other mammals in having large eyes relative to body size and that anthropoids exhibit unusually small corneas relative to eye size and body size. The large eyes of basal primates probably evolved to improve visual acuity while maintaining high sensitivity in a nocturnal context. The reduced corneal sizes of anthropoids reflect reductions in the size of the dioptric apparatus as a means of increasing posterior nodal distance to improve visual acuity. These data support the conclusion that the origin of anthropoids was associated with a change in eye shape to improve visual acuity in the context of a diurnal predatory habitus.  相似文献   

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