Contrast is the differential luminance between one object and another. Contrast sensitivity (CS) quantifies the ability to detect this difference: estimating contrast threshold provides information about the quality of vision and helps diagnose and monitor eye diseases. High contrast visual acuity assessment is traditionally performed in the eye care practice, whereas the estimate of the discrimination of low contrast targets, an important complementary task for the perception of details, is far less employed. An example is driving when the contrast between vehicles, obstacles, pedestrians, and the background is reduced by fog. Many conditions can selectively degrade CS, while visual acuity remains intact. In addition to spatial CS, “temporal” CS is defined as the ability to discriminate luminance differences in the temporal domain, i.e., to discriminate information that reaches the visual cortex as a function of time. Likewise, temporal sensitivity of the visual system can be investigated in terms of critical fusion frequency (CFF), an indicator of the integrity of the magnocellular system that is responsible for the perception of transient stimulations. As a matter of fact, temporal resolution can be abnormal in neuro-ophthalmological clinical conditions. This paper aims at considering CS and its application to the clinical practice.

Contrast is the differential luminance between one object and another. Contrast sensitivity (CS) quantifies the ability to detect this difference: estimating contrast threshold provides information about the quality of vision and helps diagnose and monitor eye diseases. High contrast visual acuity assessment is traditionally performed in the eye care practice, whereas the estimate of the discrimination of low contrast targets, an important complementary task for the perception of details, is far less employed. An example is driving when the contrast between vehicles, obstacles, pedestrians, and the background is reduced by fog. Many conditions can selectively degrade CS, while visual acuity remains intact. In addition to spatial CS, “temporal” CS is defined as the ability to discriminate luminance differences in the temporal domain, i.e., to discriminate information that reaches the visual cortex as a function of time. Likewise, temporal sensitivity of the visual system can be investigated in terms of critical fusion frequency (CFF), an indicator of the integrity of the magnocellular system that is responsible for the perception of transient stimulations. As a matter of fact, temporal resolution can be abnormal in neuro-ophthalmological clinical conditions. This paper aims at considering CS and its application to the clinical practice.

Conjunctival flaps have previously proven to be effective in preserving the globe for individuals with severe ocular surface disease. Infectious keratitis, neurotrophic keratitis, nontraumatic corneal melts, descemetoceles, perforations, and corneal burns are all indications for this procedure. The flaps promote nutrition, metabolism, structure, and vascularity, as well as reduce pain, irritation, inflammation, and infection. Furthermore, patients avoid the emotional and psychological repercussions of enucleation or evisceration, while requiring fewer postoperative medications and office visits. Currently, fewer flaps are performed due to the emergence of additional therapeutic techniques, such as serum tears, bandage lenses, corneal grafting, Oxervate, amniotic membrane, and umbilical cord grafting. However, despite newer conservative medical methods, conjunctival flaps have been demonstrated to be useful and advantageous. Moreover, future technologies and approaches for globe preservation and sight restoration after prior conjunctival flaps are anticipated. Herein, we review the history, advantages, and disadvantages of various surgical techniques: Gundersen’s bipedicle flap, partial limbal advancement flap, selective pedunculated conjunctival flap with or without Tenon’s capsule, and Mekonnen’s modified inferior palpebral-bulbar conjunctival flap. The surgical pearls and recommendations offered by the innovators are also reviewed, including restrictions and potential complications. Procedures for visual rehabilitation in selective cases after conjunctival flap are reviewed as well.

Conjunctival flaps have previously proven to be effective in preserving the globe for individuals with severe ocular surface disease. Infectious keratitis, neurotrophic keratitis, nontraumatic corneal melts, descemetoceles, perforations, and corneal burns are all indications for this procedure. The flaps promote nutrition, metabolism, structure, and vascularity, as well as reduce pain, irritation, inflammation, and infection. Furthermore, patients avoid the emotional and psychological repercussions of enucleation or evisceration, while requiring fewer postoperative medications and office visits. Currently, fewer flaps are performed due to the emergence of additional therapeutic techniques, such as serum tears, bandage lenses, corneal grafting, Oxervate, amniotic membrane, and umbilical cord grafting. However, despite newer conservative medical methods, conjunctival flaps have been demonstrated to be useful and advantageous. Moreover, future technologies and approaches for globe preservation and sight restoration after prior conjunctival flaps are anticipated. Herein, we review the history, advantages, and disadvantages of various surgical techniques: Gundersen’s bipedicle flap, partial limbal advancement flap, selective pedunculated conjunctival flap with or without Tenon’s capsule, and Mekonnen’s modified inferior palpebral-bulbar conjunctival flap. The surgical pearls and recommendations offered by the innovators are also reviewed, including restrictions and potential complications. Procedures for visual rehabilitation in selective cases after conjunctival flap are reviewed as well.

Perception is the ability to see, hear, or become aware of external stimuli through the senses. Visual stimuli are electromagnetic waves that interact with the eye and elicit a sensation. Sensations, indeed, imply the detection, resolution, and recognition of objects and images, and their accuracy depends on the integrity of the visual system. In clinical practice, evaluating the integrity of the visual system relies greatly on the assessment of visual acuity, that is to say on the capacity to identify a signal. Visual acuity, indeed, is of utmost importance for diagnosing and monitoring ophthalmological diseases. Visual acuity is a function that detects the presence of a stimulation (a signal) and resolves its detail(s). This is the case of a symbol like “E”: the stimulus is detected, then it is resolved as three horizontal bars and a vertical bar. In fact, within the clinical setting visual acuity is usually measured with alphanumeric symbols and is a three-step process that involves not only detection and resolution, but, due to the semantic content of letters and numbers, their recognition. Along with subjective (psychophysical) procedures, objective methods that do not require the active participation of the observer have been proposed to estimate visual acuity in non-collaborating subjects, malingerers, or toddlers. This paper aims to explain the psychophysical rationale underlying the measurement of visual acuity and revise the most common procedures used for its assessment.

Perception is the ability to see, hear, or become aware of external stimuli through the senses. Visual stimuli are electromagnetic waves that interact with the eye and elicit a sensation. Sensations, indeed, imply the detection, resolution, and recognition of objects and images, and their accuracy depends on the integrity of the visual system. In clinical practice, evaluating the integrity of the visual system relies greatly on the assessment of visual acuity, that is to say on the capacity to identify a signal. Visual acuity, indeed, is of utmost importance for diagnosing and monitoring ophthalmological diseases. Visual acuity is a function that detects the presence of a stimulation (a signal) and resolves its detail(s). This is the case of a symbol like “E”: the stimulus is detected, then it is resolved as three horizontal bars and a vertical bar. In fact, within the clinical setting visual acuity is usually measured with alphanumeric symbols and is a three-step process that involves not only detection and resolution, but, due to the semantic content of letters and numbers, their recognition. Along with subjective (psychophysical) procedures, objective methods that do not require the active participation of the observer have been proposed to estimate visual acuity in non-collaborating subjects, malingerers, or toddlers. This paper aims to explain the psychophysical rationale underlying the measurement of visual acuity and revise the most common procedures used for its assessment.

Background: Pterygium is a sun-related ocular surface disease secondary to ultraviolet (UV) radiation exposure. Outdoor occupational UV exposure is known to occur secondary to sun exposure. We present a unique case of pterygium associated with indoor occupational light-emitting diode (LED) exposure not previously described in the literature.

Case Description: A mobile phone repairer presented with blurred vision and a superotemporal pterygium of his dominant left eye associated with a magnifying glass LED work lamp was diagnosed. This was excised routinely with conjunctival autografting to the defect. Histopathology confirmed benign pterygium and recovery was uncomplicated with resolution of blur.

Conclusions: The development of pterygium in our patient may have arisen due to the LED lamp’s wavelengths possibly falling within the UV as well as the upper end of the visible light radiation spectrum. Given the increasing reliance on LED light sources in modern life, ocular conditions arising from exposure to these radiation sources may now need to be listed in the differential diagnoses of patients with pterygium. Appropriate UV protection counselling for these types of lights may also now need to be considered.

Background: Pterygium is a sun-related ocular surface disease secondary to ultraviolet (UV) radiation exposure. Outdoor occupational UV exposure is known to occur secondary to sun exposure. We present a unique case of pterygium associated with indoor occupational light-emitting diode (LED) exposure not previously described in the literature.

Case Description: A mobile phone repairer presented with blurred vision and a superotemporal pterygium of his dominant left eye associated with a magnifying glass LED work lamp was diagnosed. This was excised routinely with conjunctival autografting to the defect. Histopathology confirmed benign pterygium and recovery was uncomplicated with resolution of blur.

Conclusions: The development of pterygium in our patient may have arisen due to the LED lamp’s wavelengths possibly falling within the UV as well as the upper end of the visible light radiation spectrum. Given the increasing reliance on LED light sources in modern life, ocular conditions arising from exposure to these radiation sources may now need to be listed in the differential diagnoses of patients with pterygium. Appropriate UV protection counselling for these types of lights may also now need to be considered.

Background: Femtosecond laser astigmatic keratotomy (FSAK) and toric intraocular lens (IOL) implantation have been studied individually for comparison to treat astigmatism at cataract surgery. We report a case of surgically induced high corneal astigmatism by laser thermal keratoplasty (LTK) in a patient with cataract who was successfully treated with simultaneous combination of FSAK and toric IOL implantation with femtosecond laser-assisted cataract surgery (FLACS). This is the first report of both procedures combined simultaneously, with or without history of LTK.

Case Description: A 68-year-old male presented with a history of LTK with two enhancements each eye in 2004, with subsequent surgically induced high corneal astigmatism, and with age-related nuclear cataract of both eyes. IOL master demonstrated +7.71 diopters of astigmatism at 163 degree right eye and +3.29 diopters of astigmatism at 4 degree left eye. After extensive discussion of the risks and benefits, the patient agreed to undergo FLACS with FSAK with two 61 degrees of relaxation incisions (RIs) and toric IOL (Alcon SN6AT9) right eye; FLACS with toric IOL (Alcon SN6AT7) alone left eye. At 2-year follow-up, uncorrected visual acuity was 20/30 right eye, 20/25 left eye. His best corrected visual acuity was 20/25 (+0.25 +1.00 axis 21) right eye and 20/20 (plano +0.25 axis 90) left eye; his best corrected near visual acuity was J1+ with add +2.50 diopters right eye and left eye.

Conclusions: Patients with age-related cataract and LTK induced high corneal astigmatism can hardly be sufficiently treated with FSAK or toric IOL alone at the time of cataract surgery. An effective way is to combine large FSAK and toric IOL of the highest cylindrical power of T9, in our case, simultaneously, which can achieve an excellent long term visual outcome.

Background: Femtosecond laser astigmatic keratotomy (FSAK) and toric intraocular lens (IOL) implantation have been studied individually for comparison to treat astigmatism at cataract surgery. We report a case of surgically induced high corneal astigmatism by laser thermal keratoplasty (LTK) in a patient with cataract who was successfully treated with simultaneous combination of FSAK and toric IOL implantation with femtosecond laser-assisted cataract surgery (FLACS). This is the first report of both procedures combined simultaneously, with or without history of LTK.

Case Description: A 68-year-old male presented with a history of LTK with two enhancements each eye in 2004, with subsequent surgically induced high corneal astigmatism, and with age-related nuclear cataract of both eyes. IOL master demonstrated +7.71 diopters of astigmatism at 163 degree right eye and +3.29 diopters of astigmatism at 4 degree left eye. After extensive discussion of the risks and benefits, the patient agreed to undergo FLACS with FSAK with two 61 degrees of relaxation incisions (RIs) and toric IOL (Alcon SN6AT9) right eye; FLACS with toric IOL (Alcon SN6AT7) alone left eye. At 2-year follow-up, uncorrected visual acuity was 20/30 right eye, 20/25 left eye. His best corrected visual acuity was 20/25 (+0.25 +1.00 axis 21) right eye and 20/20 (plano +0.25 axis 90) left eye; his best corrected near visual acuity was J1+ with add +2.50 diopters right eye and left eye.

Conclusions: Patients with age-related cataract and LTK induced high corneal astigmatism can hardly be sufficiently treated with FSAK or toric IOL alone at the time of cataract surgery. An effective way is to combine large FSAK and toric IOL of the highest cylindrical power of T9, in our case, simultaneously, which can achieve an excellent long term visual outcome.

A blepharoplasty flap has been previously reported as a useful reconstruction approach for anterior lamellar defects lying between the lash line and the eyelid crease. We herein describe a variation of the blepharoplasty flap and suggest its use as an adjunct in the reconstruction of full-thickness lateral upper eyelid defects. Technique description and retrospective interventional case series. The reconstruction technique was used by an experienced oculoplastics surgeon (ASL) in 3 adults with malignant lesions involving the lateral upper eyelid margin, resulting in a post-excision 50% full-thickness defect between November 2017 and June 2020. The posterior lamella was reconstructed using an ipsilateral free tarsal graft and an inferiorly hinged transposition periosteal flap. The anterior lamella reconstruction was then performed using a local advancement flap utilizing the principles of upper blepharoplasty and Burow’s triangle. Almost full eyelid excursion and full gentle closure were evident at 1–2 weeks follow-up in all three cases. One case later developed 1–2 mm of gentle closure lagophthalmos and was managed successfully with topical lubricants. In all patients, the final eyelid contour and symmetry were adequate, with only minimal scarring, evident already 3 to 4 months postoperative. There were no major complications or need for revisions. The technique described herein highlights the utility of the blepharoplasty flap for lateral, full-thickness upper eyelid defects. This logical variation enables the reconstruction of significant defects using only local tissue, obeying the “like with like” principle, and helps avoid the need for a bridging flap. We provide preliminary evidence of the potential of a good cosmetic outcome of upper lid appearance and contour, together with a fast recovery of appropriate eyelid function.

A blepharoplasty flap has been previously reported as a useful reconstruction approach for anterior lamellar defects lying between the lash line and the eyelid crease. We herein describe a variation of the blepharoplasty flap and suggest its use as an adjunct in the reconstruction of full-thickness lateral upper eyelid defects. Technique description and retrospective interventional case series. The reconstruction technique was used by an experienced oculoplastics surgeon (ASL) in 3 adults with malignant lesions involving the lateral upper eyelid margin, resulting in a post-excision 50% full-thickness defect between November 2017 and June 2020. The posterior lamella was reconstructed using an ipsilateral free tarsal graft and an inferiorly hinged transposition periosteal flap. The anterior lamella reconstruction was then performed using a local advancement flap utilizing the principles of upper blepharoplasty and Burow’s triangle. Almost full eyelid excursion and full gentle closure were evident at 1–2 weeks follow-up in all three cases. One case later developed 1–2 mm of gentle closure lagophthalmos and was managed successfully with topical lubricants. In all patients, the final eyelid contour and symmetry were adequate, with only minimal scarring, evident already 3 to 4 months postoperative. There were no major complications or need for revisions. The technique described herein highlights the utility of the blepharoplasty flap for lateral, full-thickness upper eyelid defects. This logical variation enables the reconstruction of significant defects using only local tissue, obeying the “like with like” principle, and helps avoid the need for a bridging flap. We provide preliminary evidence of the potential of a good cosmetic outcome of upper lid appearance and contour, together with a fast recovery of appropriate eyelid function.

目的：通过分析基于眼底彩照的人工智能（artificial intelligence,AI）在糖尿病视神经病变（diabetic optic neuropathy,DON）中的参数特征，探索AI在DON诊断中的应用价值。
方法：收集2020年1月1日至2022年4月30日就诊于东莞东华医院、横沥医院及东莞市寮步镇社区卫生服务中心并诊断为糖尿病的患者，采集其一般信息并拍摄以黄斑为中心、图片边缘距离视盘中心超过1PD的50°眼底彩照。眼底彩照由人工智能诊断系统分析获得视盘及血管检测参数，由3-4名眼底专家阅片后分为DON(+)、DON(-)两组并作糖尿病视网膜病变（diabetic retinopathy,DR）分期诊断。比较两组间视盘、血管检测参数的差异性，并分析各项参数以及DR分期与DON发病的相关性。
结果：研究共纳入糖尿病患者526人（945眼），其中男性335人，女性191人；平均年龄为51.58±12.21岁，平均病程为5.51±5.20年。所有入组病例中，DON(+)组205眼，DON(-)740眼；根据专科医师判读结果，无DR 723眼，轻度非增殖期糖尿病视网膜病变（non-proliferrative diabetic retinopathy,NPDR）7眼，中度NPDR 184眼，重度NPDR 24眼，增殖期糖尿病视网膜病变（proliferrative diabetic retinopathy,PDR）7眼。AI检测的视盘及血管参数中，水平视杯直径、垂直视杯直径、水平杯盘比、垂直杯盘比、B区视网膜静脉血管当量、B区视网膜动静脉比值在有或无DON组间存在显著差异；水平视盘直径、垂直视盘直径、弧形斑和视盘面积比、B区视网膜动脉当量在两组之间无显著差异。相关性分析发现，水平视杯直径、垂直视杯直径、水平杯盘比、垂直杯盘比、B区视网膜动静脉比值与DON患病呈负相关；B区视网膜静脉血管当量、DR分期则与其呈正相关。
结论：DON患者的视杯直径、杯盘比、B区视网膜静脉血管当量等基于眼底彩照的人工智能检测参数有显著改变；DON的发病与DR病变严重程度有关。

Objective: To explore the application value of artificial intelligence (AI) in the diagnosis of diabetic optic neuropathy (DON) by analyzing the parameter characteristics of artificial intelligence (AI) based on fundus color photos.
Methods: From January 1, 2020 to April 30, 2022, patients diagnosed with diabetes were collected in Dongguan Donghua Hospital, Hengli Hospital of Dongguan and Community Healthcare Center of Dongguan Liaobu. General information was collected and 50°field vision fundus images(centered on macula and the edge of the images were more than 1PD away from the center of the optic disc) were taken. All the images were divided into DON(+) and DON(-) groups by 3-4 ophthalmologists. All the parameters were detected and analyzed by AI system, and their differences between the two groups were compared. The correlation between each parameter and DR stage with the incidence of DON was analyzed as well.
Results: A total of 526 diabetic patients (945 eyes) were included in this study, including 335 males and 191 females. The mean age was 51.58±12.21 years, and the mean disease duration was 5.51±5.20 years. All the enrolled cases were divided into DON (+) group (205 eyes) and DON (-) group (740 eyes) . According to ophthalmologists’ interpretation, 723 eyes had no DR, 7 eyes had mild nonproliferrative diabetic retinopathy (NPDR), 184 eyes had moderate NPDR, 24 eyes had severe NPDR, 7 eyes had Proliferrative diabetic retinopathy (PDR). Among the parameters detected by AI, there were significant differences in horizontal and vertical optic cup diameter, horizontal and vertical C/D, retinal vein equivalent(RVE) in zone B, and retinal arteriole-to venule ratio(AVR) in zone B between DON(+) and DON(-) groups. There were no significant differences between the two groups in horizontal and vertical optic disc diameter, arc-shaped spot-to-disc area ratio, and retinal artery equivalent(RAE) in zone B. In the analysis of risk factors, horizontal and vertical optic cup diameter, horizontal and vertical C/D, and AVR in zone B were negatively correlated with the diagnosis of DON. RVE in zone B and the severity of DR were positively correlated with the diagnosis of DON.
Conclusions: The AI detection parameters based on fundus color photography have significant changes in the diameter of optic cup, C/D and RVE in zone B in DON patients. The incidence of DON is related to the severity of DR.

视神经炎(optic neuritis,ON)是指视神经的炎性脱髓鞘病变，是引起中青年人视力下降的主要原因。近年来，髓鞘少突胶质细胞糖蛋白抗体阳性视神经炎(myelin oligodendrocyte glycoprotein antibody-positive ON,MOG-ON)成为神经眼科领域的研究热点，国内外报道不断增加。2021年3月，中华医学会眼科学分会神经眼科学组制定了《中国脱髓鞘性视神经炎诊断和治疗循证指南(2021年)》，将MOG-ON作为新的视神经炎亚型纳入脱髓鞘性视神经炎的诊疗体系，给广大眼科医生提供了新的参考依据。因此，临床医生需要充分认识MOG抗体相关疾病和MOG-ON的临床特征和治疗进展，努力提高其诊断和治疗水平，使此类患者能够得到更多的获益，造福于更多的视神经疾病患者。

Optic neuritis(ON)is an inflammatory demyelinating disease of the optic nerve, which is the main cause of vision loss in young and middle-aged people. In recent years, myelin oligodendrocyte glycoprotein antibody-positive ON(MOG-ON)has become a research hotspot in the field of neuro-ophthalmology, and reports at home and abroad are increasing.In March 2021, the Neuro-ophthalmology Group of Ophthalmology Branch of Chinese Medical Association formulated the Evidence-Based Guidelines for the Diagnosis and Treatment of Demyelinating Optic Neuritis in China(2021) , and included MOG-ON as a new optic neuritis subtype in the diagnosis and treatment system of myelinating optic neuritis providing a new reference for the majority of ophthalmologists. Therefore, clinicians need to fully understand the clinical features and treatment progress of MOG antibody-related diseases and MOG-ON, and strive to improve the level of diagnosis and treatment, so that such patients can get more benefits and benefit more patients with optic nerve diseases.

目的：探讨耳穴压豆疗法预防眼底荧光血管造影(fluorescence fundus angiography，FFA)胃肠反应的效果。方法：选取2019年10月至2020年4月在汕头大学·香港中文大学联合汕头国际眼科中心特殊检查科行眼底荧光素血管造影检查的患者583例，实验组298例，对照组285例。对照组在检查前予常规护理措施。试验组检查前在对照组的基础上实施耳穴压豆疗法。比较两组受检者在检查期间的胃肠道反应情况及配合度和舒适度的区别。结果：试验组胃肠道反应发生率低于对照组(P<0.05)。配合度得分试验组为(2.87±0.35)分，对照组为(2.96±0.19)分，两组差异有统计学意义(P<0.001)。舒适度得分试验组为(3.93±0.70)分，对照组为(3.91±0.56)分，两组差异无统计学意义(P=0.122)。结论：耳穴压豆疗法可以降低FFA检查胃肠道反应发生率，疗效安全可靠，操作简便易行，另外，耳穴压豆方法不会造成患者检查时舒适度下降，有助于患者顺利安全完成检查。

Objective: To explore the prevention efficacy of auricular points plaster therapy on gastrointestinal reaction caused by fundus fluorescein angiography (FFA). Methods: We selected 583 patients who underwent fundus fluorescein angiography in the special examination department of our hospital from October 2019 to April 2020, and divided these patients into experimental group (n=298) and control group (n=285). The control group was given routine nursing measures before the examination. The experimental group was treated with auricular points plaster therapy on the basis routine nursing measures before the examination. The gastrointestinal reactions, degree of patient compliance and comfortableness during the examination were compared between the two groups. Results: The incidence of gastrointestinal reaction in the experimental group was lower than that of control group (P<0.05). The score of patient compliance degree was 2.87±0.35 in the experimental group and 2.96±0.19 in the control group, and there was a significant difference between the two groups (P<0.001). Degree of comfortableness was 3.93±0.70 in the experimental group and 3.91±0.56 in the control group. There was no significant difference between the two groups (P=0.122). Conclusion: Auricular points plaster therapy can reduce the incidence of gastrointestinal reaction caused by fundus fluorescein angiography, which is safe and reliable, easy to operate. In addition, the auricular points plaster therapy will not affect patient’s comfortness during examination, and will comply the patients to the examnination smoothly. is helpful for patients to complete the examination comfortably and safely

目前对于成人圆锥角膜(keratoconus，KC)的研究已经很广泛，而对于儿童KC的研究则较少，其诊断和治疗常常基于成人KC的研究基础。与成人KC相比，儿童KC的发展更迅速、造成的后果更严重，其导致的儿童视觉障碍会追随其一生，对其生活质量以及教育发展产生严重的负面影响。为了对儿童KC的治疗有较全面的认识和理解，本文针对近几年儿童KC的治疗进展，对不同治疗方法的安全性、有效性和治疗时机等方面进行综述。

At present, the research on adult keratoconus has been extensive, while the research on pediatric keratoconus is few. The diagnosis and treatment of pediatric keratoconus are often based on the study of keratoconus in adults. Pediatric keratoconus is more aggressive than adult keratoconus, resulting in visual impairment that can follow throughout their lives and have a serious negative impact on their quality of life and educational development. In this paper, according to the treatment progress of pediatric keratoconus in recent years, the safety, effectiveness,and treatment timing of different treatment methods were summarized, in order to have a more comprehensive understanding of the treatment of pediatric keratoconus.