青光眼视神经损害的三要素及其盘沿丢失的识别

诊断青光眼视神经损害的三要素为盘沿丢失、视网膜神经纤维层缺损（RNFLD）及视盘线状出血。三要素中如有两要素改变应诊断为视神经损害。对于盘沿丢失已往的教科书中均无明确描述,笔者认为识别盘沿丢失必须首先认识正常盘沿形态及其影响因素。大多数的正常盘沿形态符合ISNT法则,生理性大视杯也符合该法则。不符合ISNT法则者为盘沿丢失,或者为正常盘沿形态变异。后者如部分小视盘下方盘沿可比上方盘沿窄,判断是否上、下方盘沿丢失时应将其与鼻侧盘沿进行比较;横椭圆视盘鼻侧盘沿较宽,应上、下盘沿比较;视盘主干血管发出位置偏位、视盘倾斜也会影响盘沿形态。如果参照ISNT法则认识正常盘沿变异因素,就不难发现盘沿丢失。然而不是所有的盘沿丢失均为青光眼所致,应鉴别非青光眼性视神经损害。     

Human optic nerve fiber count and optic disc size.

In the optic nerve head, the optic nerve fibers are represented by the neuroretinal rim. The rim area showing a high interindividual variability is positively correlated with the optic disc size. This study was performed to address the question of whether, in addition to having a larger neuroretinal rim, eyes with large optic discs also have a higher count of optic nerve fibers compared to eyes with small optic nerve heads. Histologic semithin sections of 72 optic nerves of 56 cornea donors were histomorphometrically evaluated using a computerized image analyzer. The optic nerve fiber count increased significantly (P = 0.01) with enlarging optic disc size. The nerve fiber count was positively correlated with the retrobulbar optic nerve cross section area. It decreased with advancing age, with a mean annual loss of about 4,000 fibers. The nerve fiber density per disc area decreased with increasing optic disc area. Mean and median of the minimal nerve fiber diameter was larger in older subjects. The results may indicate that the optic nerve fiber count, and the anatomic reserve capacity in progressive optic neuropathies, are higher in eyes with large optic discs than in eyes with small optic nerve heads. The optic nerve fiber population decreased with advancing age. This is important for progression, pseudoprogression, and prognosis of optic neuropathies. Optic nerve fiber crowding is more marked in eyes with small optic discs than in eyes with large optic nerve heads. The age-related loss of predominantly small optic nerve fibers can potentiate the optic nerve atrophy in glaucoma and Alzheimer's disease, with both damaging preferentially large axons.     

Statistics of optic neuropathy in Seoul Municipal Boramae Hospital in Korea

In order to investigate the causative mechanisms of optic neuropathy, retrospective clinical studies including ophthalmologic examination, imaging study, and molecular biologic analyses were performed on 435 patients with optic neuropathy. The causes of optic neuropathy included optic neuritis (92 patients, 21%), hereditary optic neuropathy (85 patients, 20%), traumatic optic neuropathy (59 patients, 14%), ischemic optic neuropathy (57 patients, 13%), compressive optic neuropathy (41 patients, 9%), and toxic optic neuropathy (38 patients, 9%). In 27 patients with bilateral optic atrophy and 26 patients with unilateral optic atrophy, the causative mechanisms remained unknown. In conclusion, optic neuritis and hereditary, traumatic, and ischemic optic neuropathies were the leading causes of optic neuropathy in this study. The importance of meticulous history taking and molecular biologic testing should be stressed in the differential diagnosis of optic neuropathy.     

视神经炎的疾病分类学研究进展

视神经炎指发生于视神经的一切炎性病变,是神经眼科最常见的视神经疾病之一,也是中青年人最易罹患的视神经疾病.目前,国内外对视神经炎的分类方法主要有两种,一种按发病部位分类,可分为球后视神经炎、视乳头炎、视神经周围炎和视神经视网膜炎;另一种根据病因学分类,可分为中枢神经系统炎性脱髓鞘性疾病相关视神经炎、感染性疾病相关性视神经炎及全身系统性自身免疫性疾病相关性视神经炎.目前,我国的视神经炎病因学特点尚有待进一步开展大样本的流行病学研究.     

Evaluation of the Optic Nerve Complex in the Orbit Using Coronal Fast Magnetic Resonance Imaging

Recently available coronal fast magnetic resonance imaging (MRI) has very high spatial resolution with good contrast between the optic nerves and cerebrospinal fluid (CSF). The aim of this study was to evaluate the diagnostic value of coronal fast imaging in optic nerve diseases. Thirty-five patients with various Neuro-ophthalmic conditions including 9 with optic neuritis, 6 with optic atrophy, 5 with glaucoma, 4 with segmental optic nerve hypoplasia and 11 with other optic neuropathies including orbital apex syndrome were evaluated with the three-dimensional fast imaging employing steady-state acquisition (FIESTA) sequence in addition to standard MRI protocols. The optic nerve complexes were evaluated on coronal images of the orbits. Detailed demonstration of the optic nerve complex—the optic nerve, the perineural CSF space and dural sheath—could be readily obtained with FIESTA sequence. The acute phase of both optic neuritis and perineuritis showed enlargement of the perineural CSF space; the optic nerve was swollen in optic neuritis but not in perineuritis. Cases of optic atrophy and glaucoma showed perineural CSF space enlargement with normal optic sheath circumference and a thinner optic nerve, while optic nerve hypoplasia showed a smaller dural sheath circumference without perineural CSF space enlargement. In the cases of orbital apex syndrome optic nerve compression by the extraocular muscles was clearly shown. Coronal FIESTA imaging of the orbit is capable of delineating detailed structural changes in the optic nerve complex and is of diagnostic value for the differentiation of optic nerve diseases.     

The Evolution of an Optic Nerve Head Granuloma Due to Sarcoidosis

Sarcoidosis can affect the optic nerves by means of optic disc oedema secondary to posterior uveitis, optic disc oedema secondary to raised intracranial pressure, optic neuritis, optic atrophy secondary to compression or infiltration from a primary central nervous system lesion, and primary granuloma of the optic nerve head. The authors report the use of optical coherence tomography in assessing the response to immunosuppression in a 57-year-old woman with an optic nerve head granuloma.     

Histomorphometric analysis of optic nerve changes in experimental glaucoma

PURPOSE: To assess relative changes in different tissue components of optic nerve and their relationship to nerve fiber loss in the experimental monkey model of glaucoma. METHODS: Chronic intraocular pressure (IOP) elevation was induced by laser trabeculoplasty in the right eye of eight monkeys (Macaca fascicularis). Both experimental right optic nerves and control left optic nerves were studied. Histomorphometric analysis was performed on optic nerve cross-sections using bright field microscopy with camera lucida. Cross-sectional areas of optic nerve tissue components were estimated by point counting. Nerve fiber density was estimated by unbiased random sampling. Nerve fiber number was calculated by multiplying nerve fiber density with neuroglial area. RESULTS: Varying degrees of nerve fiber loss were seen in eight optic nerves with chronic IOP elevation. More than 50% nerve fiber loss was noted in four of eight experimental optic nerves. In these severely affected optic nerves, total optic nerve area was significantly decreased compared with control optic nerves. Among the optic nerve tissue components, only the ratio of myelinated fiber area to total optic nerve area was significantly decreased. The ratio of extraaxonal area to total optic nerve area was significantly increased, whereas the ratio of interfascicular septal area to total optic nerve area did not change significantly. For all optic nerves, differences in nerve fiber count between control and experimental optic nerves showed the strongest correlation with differences in myelinated fiber area, followed by differences in extraaxonal area and total optic nerve area. CONCLUSION: This histomorphometric study suggests the validity of the experimental monkey model of glaucoma in studying changes occurring in the nonaxonal optic nerve tissue components in human glaucomatous optic neuropathy. Glial scar tissue area was significantly increased in optic nerves with severe glaucomatous damage. Although a decrease in total optic nerve area was observed, among the optic nerve tissue components only myelinated nerve fiber area decreased significantly. Myelinated nerve fiber area also showed the strongest association with nerve fiber loss in experimental glaucoma.     

Axonal loss and neuroprotection in optic neuropathies

Most optic neuropathies do not have effective treatments. Examples are ischemic optic neuropathy, Leber hereditary optic neuropathy, optic neuritis, and traumatic optic neuropathy. In some cases, the pathophysiology of the optic nerve injury is not fully understood. For example, while the demyelinative aspects of optic neuritis have been studied, the mechanism by which the axonal loss occurs is less apparent. In other cases, although the pathophysiology of the optic neuropathy may be understood, there is difficulty treating the disease, for example, with traumatic optic neuropathy. In response to this therapeutic dearth, the concept of neuroprotection has arisen. Neuroprotection is a therapeutic paradigm for preventing death of neurons from injury and maintaining function. In optic neuropathies, the corresponding neuron is the retinal ganglion cell. These cells are unable to divide, and optic neuropathies irrevocably result in their death; therefore, the primary target of neuroprotection are retinal ganglion cells and their axons. This review emphasizes that most optic neuropathies are axonal and thus good targets for neuroprotection.     

195例视盘水肿患者的病因分析

目的 分析北京同仁眼科中心神经眼科门诊就诊的视盘水肿患者的病因。设计 回顾性病例系列。研究对象 2018年1月至12月在北京同仁眼科中心神经眼科门诊就诊的195例视盘水肿患者。方法 回顾性分析了195例视盘水肿患者的电子病历资料。对全部、不同年龄组和单双眼视盘水肿的病因分布进行分析,并对视盘水肿排名前两位的病种进行临床特征对比分析。主要指标 病因分布构成比。结果 非动脉炎性前部缺血性视神经病变（NA-AION）是视盘水肿最常见的病因（49.7%）,后面依次是视神经炎（16.4%）、颅内压增高所致视乳头水肿（7.7%）。≤20岁组,视盘水肿最常见的病因是假性视乳头水肿,＞20且≤50岁组和＞50岁组,视盘水肿的最常见病因均是NA-AION。单眼视盘水肿的最常见病因是NA-AION,双眼最常见的是颅内压增高所致视乳头水肿。与视神经炎相比,NA-AION的年龄更大,单眼水肿更常见,主诉视野遮挡更多,较少伴有眼痛。结论 神经眼科门诊最常见的视盘水肿病因是NA-AION,其次是视神经炎。发病年龄和发病眼别（单眼或双眼）对于我们寻找视盘水肿的病因具有一定的提示作用。     

Hereditary optic neuropathies

AIMS: To provide a clinical update on the hereditary optic neuropathies. METHODS: Review of the literature. RESULTS: The hereditary optic neuropathies comprise a group of disorders in which the cause of optic nerve dysfunction appears to be hereditable, based on familial expression or genetic analysis. In some hereditary optic neuropathies, optic nerve dysfunction is typically the only manifestation of the disease. In others, various neurologic and systemic abnormalities are regularly observed. CONCLUSION: The most common hereditary optic neuropathies are autosomal dominant optic atrophy (Kjer's disease) and maternally inherited Leber's hereditary optic neuropathy. We review the clinical phenotypes of these and other inherited disorders with optic nerve involvement.     

Genetic basis of hereditary optic atrophies

The most common forms of optic atrophy are: autosomatic dominant optic atrophy (ADOA, Kjer type) and maternally-inherited Leber's hereditary optic neuropathy. Rare forms of hereditary optic neuropathies are: optic atrophy X-linked and autosomatic recessive form of optic atrophy. Autosomatic dominant optic atrophy (ADOA) is the most frequent hereditary optic neuropathy. Three loci have been reported for ADOA, a major locus maps to 3q28-q29 (OPA1). The majority of mutations responsible for autosomatic dominant optic atrophy are localized in OPA1 gene. Second locus is linked to 18q12.2-q12.3 (OPA4) and a third locus on 22q12.1-q13.1 (OPA5). This study presents the actual state of knowledge about molecular changes in different forms of optic atrophy and shows hypothesis indicating the significant participation of mitochondrial dysfunction in it's pathogenesis.     

Recovery of visual field defects in ischemic optic neuropathy and idiopathic optic neuritis]

Fifty-four eyes of 41 patients with optic nerve disease demonstrating acute visual field defects without any traumatic, compressive, or other known etiology were classified into four categories. Those showing poor recovery of visual field defects were ischemic optic neuropathy which was subclassified into either anterior ischemic optic neuropathy (AION) or posterior ischemic optic neuropathy (PION) according to the ophthalmoscopic changes in the optic nerve head. Those showing good recovery of visual field defects were idiopathic optic neuritis which was subclassified into either papillitis or retrobulbar neuritis according to the ophthalmoscopic pathology of the optic disc. Patients with ischemic optic neuropathy were significantly older than those with optic neuritis. All eyes with optic neuritis showed good recovery of vision, whereas those with ischemic optic neuropathy showed varying outcomes of vision. With regard to the pattern of field defect, central or paracentral scotoma was predominant in all but eyes with AION in which altitude defect predominated. Pale swelling of the optic nerve head and angiographic evidence of circulatory disturbance in the optic disc or adjacent choroid were common findings in eyes with AION, whereas such findings were never observed in eyes with papillitis. The amplitude of pattern visual evoked potential was significantly lower in eyes with PION than in those with retrobulbar optic neuritis. Four patients classified as optic neuritis developed into multiple sclerosis in the follow-up study. It was concluded that poor recovery of visual field defect is one of the most convincing evidences for the diagnosis of ischemic optic neuropathy.     

Features of amiodarone-induced optic neuropathy.

PURPOSE: To report clinical features of amiodarone-induced optic neuropathy and outline the differentiation of amiodarone optic neuropathy from nonarteritic anterior ischemic optic neuropathy. METHOD: We reviewed data from 73 patients reported to have developed an optic neuropathy while taking amiodarone. RESULTS: Amiodarone optic neuropathy is characterized by an insidious onset, slow progression, bilateral visual loss, and protracted disk swelling that tends to stabilize within several months of discontinuing the medication. Nonarteritic ischemic optic neuropathy is characterized by acute, unilateral visual loss that is usually complete at onset, with resolution of disk edema over several weeks. CONCLUSION: Unique clinical features of amiodarone-induced optic neuropathy may help clinicians diagnose and distinguish between amiodarone-induced optic neuropathy and nonarteritic anterior ischemic optic neuropathy.     

Histopathological Changes of Inner Retina,Optic Disc,and Optic Nerve in Rabbit with Advanced Retinitis Pigmentosa

We observed the histopathological changes of retinal ganglion cells (RGCs), optic disc, and optic nerve in rabbit with advanced retinitis pigmentosa (RP). Wild-type (WT) and rhodopsin transgenic (Tg) of RP rabbits were used at age 24 months. Light and electron microscopy were used to observe the retina, optic disc, and optic nerve. RGCs were also confirmed by immunofluorescent staining with a TUJ-1 monoclonal antibody. In addition to the rod and cone degeneration, we observed the astrocyte infiltration of the optic disc due to the damage of small RGCs and nerve fibres and atrophy of small optic nerve fibres. They subsequently lead to the optic disc excavation and atrophy of the optic nerve. Consequently, our histopathological study clarified that not only the outer retina but also the inner retina, the optic disc, and the optic nerve were also affected in the late stages of RP rabbit.     

Management of optic neuritis

To improve understanding and effectiveness of therapy in optic nerve disease, various causes of so-called optic neuritis should be identified when possible. The clinical characteristics of demyelinating optic neuropathy can be contrasted with those of ischemic optic neuropathy, nutritional optic neuropathy, true optic nerve inflammation (e.g., luetic), optic nerve infiltration with tumor, and compression neuropathy caused by adjacent tumor. Radiologic studies and other means of investigating patients with optic neuritis are reviewed. Arguments in favor of, and against, treatment of presumed demyelinating optic neuritis are presented along with representative corticosteroid treatment regimens. The natural tendency toward spontaneous improvement of optic neuritis makes the effect of treatment difficult to assess.     

Pseudoduplication of the optic nerve head.

BACKGROUND: Pseudo-doubling of the optic nerve head is a spectacular clinical entity, in which a lesion resembling an optic disk appears adjacent to the true optic disk. CASE REPORT: A case of unilateral pseudo-doubling of the optic disk with bilateral optic nerve pits is presented. CONCLUSIONS: The lesion is congenital, and represents a chorioretinal coloboma with optic disk involvement. Pseudo-doubling can be differentiated from true doubling of the optic nerve by the imaging techniques of ultrasonography, computerized tomography, and magnetic resonance imaging.     

The Use of Diffusion MRI in Ischemic Optic Neuropathy and Optic Neuritis

Ischemic optic neuropathy and optic neuritis are the most common causes of unilateral non-glaucomatous visual loss. While they have distinctive clinical features, they also share some overlapping profiles that make it difficult to clinically distinguish these two entities. MRI with gadolinium has been proven to be helpful to confirm the diagnosis of optic neuritis, but ischemic optic neuropathy remains a clinical diagnosis. Diffusion MRI, a newly advanced technique, has been used in studying the pathophysiology of optic neuritis, but its use in ischemic optic neuropathy is limited. Diffuse MRI may potentially be of help to diagnose ischemic optic neuropathy.     

The use of diffusion MRI in ischemic optic neuropathy and optic neuritis

Ischemic optic neuropathy and optic neuritis are the most common causes of unilateral non-glaucomatous visual loss. While they have distinctive clinical features, they also share some overlapping profiles that make it difficult to clinically distinguish these two entities. MRI with gadolinium has been proven to be helpful to confirm the diagnosis of optic neuritis, but ischemic optic neuropathy remains a clinical diagnosis. Diffusion MRI, a newly advanced technique, has been used in studying the pathophysiology of optic neuritis, but its use in ischemic optic neuropathy is limited. Diffuse MRI may potentially be of help to diagnose ischemic optic neuropathy.     

非青光眼性大视杯临床分析

目的 探讨非青光眼性疾病引起视杯扩大的病因以及鉴别要点,为临床识别非青光眼性大视杯提供依据。设计 回顾性病例系列。研究对象 12例（19眼）非青光眼大视杯患者。方法 分析比较这些患者的病因、视盘形态学特征以及相关影像资料。主要指标 病因、视盘形态特征以及视功能改变。结果 12例患者中,4例为视神经炎,1例视神经脊髓炎,1例Leber遗传性视神经病变,2例垂体瘤,1例基底节脑出血,1例睫状视网膜动脉阻塞合并视网膜中央静脉阻塞,1例视网膜中央动脉阻塞,1例视神经损伤。所有患者视杯呈弥漫性或局限性扩大,盘沿苍白。视野表现为与原发病相应的缺损。结论 各种视神经疾病和视网膜疾病均有可能导致大视杯,它与青光眼性大视杯的鉴别点在于盘沿色泽、有无盘沿局限性缺失以及视功能异常和视盘改变的相关性。（眼科, 2012, 21: 306-309）     

Optic neuropathies: diagnostic role of standardized echography

While large excavation, elevation and drusen of the optic disc are best detected with contact B-scan examination, standardized A-scan echography is needed to investigate properly and to differentiate optic nerve disease. Increased subarachnoidal fluid within the retrobulbar optic nerve, optic nerve atrophy and optic nerve tumors (glioma and meningioma) can be evidenced with standardized echography. Techniques and examples of ultrasound diagnosis of optic nerve disease are presented and discussed.