How Effective is Perimetry in Current Practice?

A recent study that sampled the performance of nonphysician perimetrists in community ophthalmic practices revealed that the detection rate for any defect averaged only 69%. Nasal steps were correctly identified more often (77%) than were hemianopic defects (44%). If this relatively low identification rate for hemianopias is representative, then patients with unexplained visual loss should all have CT scans regardless of the result of the visual field examination. Greater accuracy in perimetry may be achieved by improved teaching, by optimizing exploration strategies, and perhaps by automated devices.     

Empty sella syndrome with visual field disturbance

Three patients with empty sella syndrome with various visual field disturbances were reported. In one patient there was evidence of enlargement of Mariotte spots, and in the others, irregular visual field defects. These three patients were initially suspected to have intraocular tumors because of the balloonings of the sella and visual field disturbances. However, the diagnosis of empty sella was confirmed by metrizamide cisternography and metrizamide computed tomography(CT). The results indicate that the patient with enlargement of the sella on the plain skull X-ray and visual field disturbance should be examined by metrizamide cisternography and metrizamide CT scan to differentiate from the intrasellar tumor.     

Clinical research and statistical analysis of a visual field awareness system.

This article discusses the clinical research and applications of the statistical analysis of a system called "The Visual Field Awareness System." This medical lens system allows patients with a visual field loss to 1) scan toward area of the loss, to see objects sooner and more clearly, and 2) demonstrate increased function and safety. Seventy-nine percent (27 of 34) of the patients in the sample received and accepted the prism treatment. Of this group, a minimum of 70 percent (19 of 27) continue to benefit from this treatment strategy. Statistically significant predictors of success are discussed. This study demonstrates that patients suffering visual field loss may show functional benefit by the utilization of this prism treatment along with vision rehabilitation.     

首诊眼科的前床突脑膜瘤临床分析

目的 探讨首诊眼科的前床突脑膜瘤的临床表现与特点.方法 对14例病例进行回顾性分析,对其临床表现、解剖特点、影像学特点、视野及VEP表现进行分析总结.结果 在首诊眼科的14例患者中,以视力下降为主要表现的共8例,占本组病例的57.14%;头疼、头晕为主7例,占50%;以动眼神经压迫症状为主3例,占21.4%;意外发现1例.7例行中心视野检查其表现与肿瘤压迫部位基本相符,6例行VEP检查全部表现异常;14例行MRI检查,均可见占位性病变;9例CT检查者,有2例未查见占位性病变,MRI、CT两者联合有助于明确诊断.结论 对用眼疾病难以解释的视力减退和(或)眼肌麻痹的患者,应行头颅影像学检查排除有无颅内占位性病变,即使无明显眼底改变也应做视野检查,以避免漏诊.     

鼻窦肿瘤的眼部表现分析

为了早期诊断和治疗以眼部症状就诊的鼻窦肿瘤患者，分析６０例鼻窦肿瘤的眼部症状，表现为眼球突出、眼球运动障碍、复视、视力下降或丧失、上睑下垂等。其中４２例首诊于眼科。所有病例均经ＣＴ扫描和病理病检查证实。４８例采用手术治疗，３２例眼部症状改善。结果提示鼻窦肿瘤易出现眼部症状的原因，主要是由于鼻窦与眶壁、鼻窦与视神经管之间密切的解剖学关系。ＣＴ扫描有助于该病的早期诊断。     

Neuro-ophthalmology update

One source of ophthalmologic concern today is the normal computed tomography (CT) scan. The most important tests in any patient with visual loss are the history, fields, and office visit findings. A visual field examination should be obtained before a CT scan. The importance of aiming the CT machine by the history is stressed, and conservative approach to optic nerve sheath meningiomas is advised.     

Chiasmal syndrome ophthalmological and neuro-radiological aspects

The chiasmal syndrome has distinct ophthalmological features such as visual field loss, optic disc changes, decrease in visual acuity, ocular motor disturbances and exophthalmos. However, the pathological processes in the chiasmal region often give rise to differential diagnostic problems. Before the era of computer tomography (CT) these processes could only be visualized by means of indirect or invasive examination techniques. After introduction of computer tomography these processes could be identified much more easily. The ophthalmological findings are discussed. The most frequent causes of chiasmal syndrome are demonstrated on CT scan. The neuroradiological differential diagnosis of an enlarged sella turcica is given.     

VEP、F-ERG检查对眼眶爆裂性骨折患者的视功能评价分析

目的应用视觉电生理检查探讨眼眶骨折患者的临床特点及视功能的改变特点。方法记录54例眼眶骨折患者受伤原因后对其进行详细的眼科检查,按国际标准对受伤眼和健康眼进行视力检查、电生理检查、眼眶CT检查等。用未受伤眼为对照组,用SPSS软件中配对样本t检验分析受伤组和对照组的电生理检测结果。结果眼眶骨折会造成受伤眼视力明显下降,视觉电生理检查出现受伤眼的F-ERG的a波、b波振幅、P-VEP的P_(100)振幅与未受伤眼相比明显下降(P<0.01),P-VEP的P_(100)峰时与未受伤眼相比明显延迟(P<0.05)。结论眼眶骨折会对受伤眼的外观和视功能同时造成明显的影响,F-ERG a波、b波振幅的变化和P-VEP P_(100)振幅、峰时的改变能客观地反映外伤后视网膜和视神经受损害的情况。     

Psychophysical measurement of glaucomatous damage

Within the past twenty years, a number of new psychophysical test procedures have been adapted for use in perimetry and visual field testing. These procedures are designed to measure the functional properties of different types of retinal ganglion cell subpopulations. Although many of these new procedures exhibit better performance characteristics than standard automated perimetry, no single test procedure appears to be decidedly superior to all others. Comparison of multiple functions in patients with early glaucomatous damage suggests that visual function losses are not selective for specific retinal ganglion cell subpopulations in all patients. For evaluation of the efficacy of neuroprotective agents in glaucoma, one of the challenges facing the development of new psychophysical tests is to be able to distinguish visual function losses that are due to ganglion cell drop-out ("dead" cells) from those that are due to malfunctioning retinal nerve fibers ("sick" cells).     

Detecting progressive visual field loss

Involvement in shared care projects requires the optometrist to make a series of decisions one of which is an assessment of the visual field data to see if there has been any progression. To aid the optometrist in making this decision, the relationship between inter-test variability in the visual field and extent of loss has been established for the Henson CFS2000 perimeter. In this study, visual field data were collected, with a supra-threshold strategy, from 174 eyes (89 patients) over a period of 2 years, there being a total of 595 visual field records. The sample included patients with both normal and glaucomatous visual fields. The results show that analysis based upon the number of stimuli missed at 5 or more dB above the threshold estimate reveals an increasing variability with extent of loss. These data can be used by optometrists to establish the significance of any change in the number of missed stimuli from one visit to the next.     

Occipital lobe infarction after open heart surgery

The most common permanent neuro-ophthalmologic complication of cardiopulmonary bypass surgery is visual loss. Bilateral lower altitudinal visual field defects were documented in a patient who noted blurred vision following open heart surgery. A difference of opinion existed as to whether the field defects were due to retina-optic nerve or occipital lobe lesions. Two points are emphasized in this report: 1) the field defects were much easier to define on the tangent screen than on Goldman perimetry, and 2) occipital coronal high resolution CT scan confirmed bilateral upper bank calcarine cortex infarctions in this patient. Occipital coronal, thin-section, high-resolution computed tomographic scans are helpful in studying patients with occipital lobe visual field defects.     

The effects of weighting the “mean defect” visual field index according to threshold variability in the central and midperipheral visual field

Two visual field indices, the mean defect (MD) of Flammer and the mean deviation (MD) of Heijl, have found wide acceptance among perimetrists. We compared these indices in 169 visual fields from normal- and high-tension glaucomatous eyes. Visual field damage in these eyes varied from slight to severe. In computations of the mean deviation index, the threshold values are weighted by the threshold deviations obtained from normal eyes as a function of eccentricity. However, the present study shows that the differences between the two indices in the population studied are negligible. Thus, subsequent interpretation is not affected by the choice of index, and the two MD indices may be considered to be interchangeable for the types of visual fields used in this study and for program-G1 examinations carried out using Octopus automated perimeters. Since we found smaller increases in local intersubjective fluctuations as a function of eccentricity in 274 normal visual fields as compared with results published by others, caution is indicated for interpretation of the visual field using probability weighting.The authors have no proprietary interests in the equipment or companies referred to in this paper Offprint requests to: A.T. Funkhouser     

Pattern visual evoked potential in patients with posteriorly situated space-occupying lesions

The potentials evoked by pattern reversal stimulation (2/sec, 11° field, 26 high contrast checks) are described in 22 patients with intracranial space-occupying lesions lying posterior to the optic chiasm. Seventeen (77%) of these patients had clinically demonstrable visual field defects. The nature and position of the lesion was defined by CT scan, by cerebral angiography, or at operation. Completely normal pattern visual evoked potentials (VEPs) were recorded in four patients (18%), all of whom had full visual fields. Definitely abnormal VEPs occurred in 12 patients (55%), 11 with visual field defects. The remaining six patients (27%), all with visual field defects, had VEPs that were inconsistently abnormal and they are rated as equivocal. The findings are discussed with particular attention to the importance of stimulus and recording parameters.     

Dermatochalasis causing apparent bitemporal hemianopsia

We describe a previously unreported cause of apparent bitemporal hemianopsia. Three patients with bilateral dermatochalasis underwent Humphrey visual field (HVF) testing in anticipation of corrective blepharoplasty. Unexpectedly, the HVF showed bitemporal hemianopsia in each case, prompting magnetic resonance imaging of the brain in one case. The scan was negative. The HVF tests were repeated with the upper eyelids taped in elevation, and were normal. We conclude that the bitemporal hemianopic defects in our patients resulted from the testing strategy employed by the HVF analyzer software to measure the visual field. Reasons for these artifactual results are discussed. Clinicians should be aware of this uncommon cause of bitemporal hemianopic visual field defects.     

Measurements of Reversibility of Optic Disc Cupping and Pallor in Ocular Hypertension and Glaucoma

Four cases are presented of young and elderly glaucoma patients who had both surgical and medical therapy and showed reversal of cupping and pallor of the optic disc. The cupping was measured by photogrammetry and the pallor by computerized image analysis from photographs of the optic disc. Two patients showed regression of visual field loss. The optic disc and visual field changes corresponded to the changes in ocular pressures, generally showing worsening with an increase in ocular pressure. With a decrease in ocular pressure there was regression of visual field loss and a decrease in cupping; pallor did not decrease consistently. The changes in cupping and pallor in some patients followed similar courses but in others behaved in an independent manner. It is proposed that these new sensitive and reproducible techniques for measuring changes in the optic disc may allow the detection of disc changes early in the disease, prior to visual field loss. If treatment is begun at this time, reversal of optic disc changes may occur.     

Autoimmune retinal dysfunction in sarcoid chorioretinopathy

BACKGROUND: Visual loss, photophobia and night-blindness in a middle-aged patient with a previous history of cancer are highly suggestive of cancer-associated retinopathy. HISTORY AND SIGNS: A 63-year-old man complained of slowly progressive bilateral visual loss, photophobia and night-blindness. His past medical history was remarkable for surgical and medical treatment of a carcinoma of the base of his tongue nine years earlier. Visual acuity was 0.3 RE and 0.15 LE, with constricted visual field in both eyes. Ocular examination and fluorescein angiography were non-relevant. Electroretinography revealed diffuse cone and rod dysfunction. ICG angiography showed multiple small widespread hyperfluorescent spots. A chest CT scan revealed multiple focal lesions which were biopsied. Histological diagnosis was sarcoidosis. THERAPY AND OUTCOME: Upon systemic steroid therapy, visual function gradually improved, and ICG anomalies disappeared. Vision recovered to 1.0 RE and 0.8 LE with normal visual field in both eyes. CONCLUSION: Sarcoidosis may present as an autoimmune retinal dysfunction with photophobia and night blindness as the presenting symptoms.     

The perimetry of the blind spot. A comparison of kinetic and static, computerized stratgies

The reproducibility of perimetric results on the blind spot has been investigated under controllnt well-trained perimetrists on 178 eyes of 107 patients; the same eyes and patients were examined twice with the computer perimeter as well. Perimetric results obtained from 158 eyes were considered for statistics. There was qualitative agreement based on the alternative 'normal' or 'pathological' in kinetic perimetry in 74% of the double examinations and in 89% in computer perimetry. Identical size of the blind spot in repeated examinations was found in 34% with the Goldmann perimeter and in 78% with the computer perimeter. Observer variability of the static computer perimetry of the blind spot was compared with the variability of the results on the rest of the central visual field.     

视网膜神经纤维层定量测定在青光眼方面的应用

青光眼的主要病理过程是视网膜节细胞轴突（即视神经纤维）的丢失，故测量视网膜神经纤维层（ｒｅｔｉｎａｌｎｅｒｖｅｆｉｂｅｒｌａｙｅｒ，ＲＮＦＬ）来确定轴突丢失的程度在青光眼的早期诊断和治疗上具有非常重要的意义。近年来，计算机图像分析技术应用于眼科，它能对ＲＮＦＬ作出客观的量化检测。该文综述有关文献，就ＲＮＦＬ定量测定方法的原理，以及它们在青光眼ＲＮＦＬ损害检测方面的应用情况作一介绍。     

颅外伤合并间接性视神经损伤

目的 探讨颅外伤合并间接性视神经损伤的临床诊断和治疗。方法 回顾分析了颅外伤合并间接性视神经损伤36例（36眼）的临床资料。11例行视神经减压术，25例接受药物治疗。结果 全部患者伤侧眼的相对瞳孔传入障碍（RAPD）阳性；眼眶CT扫描显示有眶壁和／或鼻窦骨折。药物治疗组有8例（32．00％）视力提高1行，其余17例（68．00％）视力无改善，手术治疗组有1例（909％）由数指／1．5m提高到03，5例（45．46％）恢复了瞳孔直接对光反应，1例（9．09％）恢复了VEP波，其余4例（36．36％）视力无改善。结论 对颅外伤患者应进行RAPD检查及眼眶CT扫描，确定有无间接性视神经损伤。皮质类固醇和视神经减压联合应用可能更有利于视功能的恢复。     

Incidental diagnosis of orbital lymphoma during blepharoplasty

PURPOSE: To describe the incidental diagnosis of orbital lymphoma in 3 patients, in whom unusual findings at the time of blepharoplasty led to the diagnosis of orbital lymphoma. METHODS: A retrospective review of the medical records of 3 patients. RESULTS: Two patients presented with bilateral dermatochalasis that obscured the upper visual field and was more prominent on one side. One patient presented with bilateral ptosis and dermatochalasis. All three patients underwent bilateral upper blepharoplasty. In one patient, bilateral ptosis repair was performed in addition to upper blepharoplasty. Blepharoplasty specimens were sent for histopathologic analysis because of the unusual appearance of the preaponeurotic fat at the time of surgery. Histopathology showed low-grade B-cell lymphocytic lymphoma in all three cases. Postoperative CT scan showed a mass in the lacrimal fossa in one patient. None of the patients had evidence of systemic involvement. Two patients were treated with external beam radiotherapy with good results. One patient recently diagnosed with orbital lymphoma was referred to the oncology clinic for further treatment.CONCLUSIONS: Histopathologic evaluation of blepharoplasty specimens is highly recommended in cases in which the orbital fat has an unusual appearance, color, or consistency at the time of surgery.