自动静态视野随诊检查结果的可靠性研究

目的　探讨青光眼与疑似青光眼患者自动静态视野随诊检查结果的可靠性。方法回顾性分析 1994年 8月至 2 0 0 0年 6月 ,使用Octopus 1 2 3全自动静态视野计连续检测次数≥ 2次的青光眼患者 (82只眼 )和疑似青光眼患者 (80只眼 )的视野检测资料 ,根据检测次数分为A、B、C组 ,比较各组患者视野检测结果的假阳性反应率 (FP)、假阴性反应率 (FN)及可靠性因子 (RF)。结果依据瑞士Interzeag公司提供的参考标准 ,疑似青光眼患者组 197份视野检测结果中 ,不可靠视野检测结果 10份 (5 1% ) ;青光眼患者 2 15份视野检测结果中 ,不可靠视野检测结果 39份 (18 1% )。青光眼患者各组的假阴性反应率远高于疑似青光眼患者 (P <0 0 1)。结论　多数疑似青光眼患者自动静态视野随诊检查结果可靠 ,少数不可靠的视野检测结果属偶然现象 ;假阴性反应结果与青光眼患者视野状态有关。     

The feasibility of short automated static perimetry in children

OBJECTIVE: To evaluate the feasibility of short automated static perimetry using tendency-oriented perimetry in the pediatric population. DESIGN: Prospective observational case series. PARTICIPANTS: Fifty normal children age 6 through 12 years. TESTING: Subjects underwent testing with the Octopus TOP-32 program on the Octopus 1-2-3 automated perimeter. Testing was performed in a typical clinical setting without adaptations to the perimeter, prolonged training, or the use of custom seating. Each eye was tested twice. MAIN OUTCOME MEASURES: Ability to complete automated static perimetry tests with both eyes. Mean sensitivity, mean defect, and loss of variance; gray scale and numeric representations of the field; duration of each test and of the entire session; subjective assessment of each test as normal or abnormal; calculation of test specificity. Comparisons by age and test number were performed. RESULTS: All subjects successfully completed all four tests. The mean duration for each test was 2:30+/- 0.23 minutes. The average time for the whole session, including training, testing both eyes twice, and rest periods, was 25.8+/-4.87 minutes. Improvement in the specificity of the test (fewer abnormal tests in normal children) occurred in direct relation to subject age (R = 0.5). CONCLUSIONS: Automated static perimetry using short, tendency-oriented programs can be successfully performed in normal children age 6 through 12 years in a typical clinical setting. Age was the best predictor of the mean sensitivity, reproducibility, and accuracy of the test, with the most reliable results obtained after 7 years of age. In children 6 to 7 years old, significant interindividual variability was present, and testing success was more dependent on the child's maturity and ability to concentrate. Short automated perimetry seems to be a promising tool for the evaluation of peripheral vision in pediatric patients.     

Sources of error in automated static perimetry

Several sources of errors in interpreting computerized visual fields (learning effect, miotic pupil, sub-optimal refraction, dirty contact lenses, inadequate patient cooperation, anatomical obstacle, and choice of the wrong program) are described with the help of examples. Their identification should result in more reliable diagnoses.     

The effect of Goldmann applanation tonometry on automated static threshold perimetry

Automated static threshold perimetry was performed in both eyes of 10 normal and 12 ocular hypertensive subjects treated with a topical beta-blocker, before and after Goldmann applanation tonometry of their right eyes. Both objective statistical comparison and subjective evaluation of the resultant visual fields showed no detrimental effect on visual field test results after applanation tonometry.     

Time-related variation in normal automated static perimetry

The effects of phase of eye test and order of eye examined were investigated in 38 normal subjects using a customized 30-point central threshold program of the Humphrey Field Analyzer 640. This program, designed to be completed within 5 minutes, was successively repeated three times for each eye (i.e., three phases for each eye) at two visits separated by an interval of approximately 2 weeks. Both global and pointwise group mean sensitivity decreased in a time-related manner, deterioration being greater for the second eye at each visit, for both 200 ms and 100 ms stimulus durations.     

Evaluation of diabetic retinopathy by automated static perimetry

Decibel values of threshold sensitivity depression of the retina were evaluated in 69 eyes with NIDDM using the Humphrey automated static perimeter. The eyes were classified into three groups: group I (GI) consisting of 32 eyes with no retinopathy or with stages 1 and 2 of simple diabetic retinopathy, group II (GII) consisting of 21 eyes with stage 3 of simple retinopathy or pre-proliferative retinopathy and group III (GIII) consisting of 16 eyes treated by panretinal photocoagulation using an argon laser. The average age in each group was 60 years and all eyes had a visual acuity of over 0.6. As controls, 16 normal eyes were examined. In comparison with the values of the control, the mean of the sum of decibel threshold sensitivity in the macular retina significantly decreased by 5% in GI, 7.8% in GII, and 24.3% in GIII. It was found that the mean of the sum of decibels in the central retina decreased by 8.2% in GI and 15.5% in GII. The sum of decibels in the mid-peripheral retina showed a decrease of 11.4% in GI and 27.5% in GII. In addition, the decibel values of threshold sensitivity of the lower half of the retina tended to decrease more easily than those of the upper half of the retina in the parafoveal and the macular areas. It was also suggested that decibel values of threshold sensitivity of the retina may decrease shortly after PRP in the paramacular area (located about 10 degrees from the fovea) but not in the foveal area.     

Optimization of the presentation pattern in automated static perimetry

Knowledge of the luminance sensitivity distribution over the retina on the one hand and of the fluctuations and mistakes in the answers of the patient on the other enable an optimal pattern of presentation of test spot intensities to be determined which gives the best information gain per answer. Optimization with various initial conditions shows that the reliability of the patient's answers has a substantial influence on information gain and on accuracy of the result. The presentation pattern is less critical, however, and it is possible to obtain exact results with a variety of patterns by appropriate choice of correction steps.     

Prediction of future scotoma on conventional automated static perimetry using frequency doubling technology perimetry

AIM: To see if scotoma detected with frequency doubling technology (FDT) is confirmed by Humphrey field analyser (HFA) 3 years later. METHODS: Subjects were first examined with the screening C-20-1 program of FDT. The visual field was examined annually for 4 years using HFA program C30-2. The central 58 test points in HFA were assigned to one of the 17 clusters corresponding to FDT test points. Each cluster was represented as the lowest probability symbol of total deviation (TD) of the HFA test points included in the cluster. Clusters were graded normal, suspected scotoma, and scotoma depending on probability of TD-5% or more, 5%-1%, less than 1%, respectively. Relative risk (RR) of abnormality on FDT for future scotoma on HFA was estimated. RESULTS: 80 eyes of 42 patients were followed up for 4 years. While 4.0% of normal clusters of HFA with normal FDT results developed into scotoma cluster, 20.8% of normal clusters with abnormal FDT results developed into scotoma cluster with HFA at the third year. RR for future scotoma was 5.24 (95% CI, 2.75 to 10.0, p<0.05). CONCLUSION: An abnormal result in FDT shows a high risk of future scotoma on HFA after 3 years even if the original HFA perimetry showed normal results.     

An application of threshold-versus-intensity functions in automated static perimetry

Increment thresholds were measured over a range of adapting illuminances using a modified automated static perimeter. The data were fitted to a threshold versus intensity model (logT - logT(0) + log((A + A(0))/A(0))n) and the values logT(0) and logA(0) estimated. The effect of eccentricity and age on logT(0) and logA(0) was examined in normal subjects. A small group of patients with ocular disease were then assessed. Macular degeneration appeared to act as disease processes acting near the photoreceptor (d1 model). Glaucoma seemed to act near the site of retinal gain (d3 model). This analysis method may be of value in developing light adaptation strategies in people with ocular disease.     

Feasibility and outcome of automated static perimetry in children using continuous light increment perimetry (CLIP) and fast threshold strategy

PURPOSE: Visual field testing in children is always a challenge as testing is hampered by fatigue effects, easy distraction and lack of comprehension. For that reason new testing strategies for automated perimetry have mainly been evaluated on adults. We tested the feasibility and outcome of automated static perimetry in children in a standard clinical setting. METHODS: Twenty-eight children aged 5-14 years were examined at the Twinfield perimeter, including healthy children, children with unilateral pathologies (normal eye tested) and children with strabismus. Fast threshold strategy (FT) and continuous light increment perimetry (CLIP) strategy were used in a randomized order. One eye per subject was examined and each test was performed twice. RESULTS: Reliable results were obtained in many children starting from the age of 8 years. In children aged 13 years and over, adult testing strategies were possible in most cases with good reproducibility. No significant difference was found between the children with strabismus and the other children. Mean sensitivity (MS) increased and fixation losses decreased as a function of age. Continuous light increment perimetry showed a lower number of abnormal fields and fewer false-positive errors compared to FT. CONCLUSION: Automated static perimetry is possible in many children in a clinical setting using a commercially available Twinfield perimeter in a session of clinically practical duration. Test performance was not only dependent on age, but also on the child's maturity and ability to concentrate. Especially in children up to the age of 8 years, testing with the ramp stimulus (CLIP) was easier than with a staircase strategy (FT).     

Macular diseases--application of automated static perimetry and optical coherence tomography

The usefulness of automated static perimetry and optical coherence tomography in the management of macular diseases has been described. Scotomata in eyes with central serous chorioretinopathy could be evaluated with central 10-degree automated static perimetry. The degree of visual field defects in eyes with the disease varied greatly with mean deviation of -10 dB or less in as many as 10% of the subjects. Although retinitis pigmentosa is a diffuse retinal dystrophy, eyes with a moderately advanced stage of retinitis pigmentosa should be managed as a macular disease, because the functioning retina is confined within the vascular arcade. The progressive nature in this stage of the disease could be demonstrated with a central 10-degree automated static perimetry measured once or twice a year and the use of univariate linear regression of mean deviation, in half of the patients with a mean follow-up period of 5 years. Functional recovery in eyes with exudative age-related macular degeneration after laser surgery or submacular surgery could be evaluated with central 10-degree automated static perimetry. Eyes with increased mean deviation in spite of reduced visual acuity after therapeutic intervention should also be evaluated. Macular function could also be evaluated using a color test. A newly developed color saturation discrimination test was applied to patients with age-related macular degeneration, retinitis pigmentosa, and cone dystrophy. The degree of dyschromatopsia was less in eyes with age-related macular degeneration than in those with retinitis pigmentosa or cone dystrophy with the same level of acuity loss. The highly protrusive nature of the orange-red nodule in eyes with idiopathic polypoidal choroidal vasculopathy was demonstrated with dimensional measurement with OCT. The degree of protrusion was greater than in eyes with serous pigment epithelial detachment, which suggests that the polypoidal lesion is covered with rigid tissues including Bruch's membrane. Parafoveal retinal sensitivity obtained with automated static perimetry was studied in correlation with retinal thickness measured using OCT in eyes with branch retinal vein occlusion showing macular edema without macular non-perfusion or massive retinal hemorrhages. The increased retinal thickness due to macular edema is closely correlated with retinal sensitivity both at the fovea and in the parafoveal area. Eighty-nine phakic eyes of 46 patients with retinitis pigmentosa patients were studied to detect cystoid macular edema using OCT. Cystoid lesions were observed in the macula in 12 eyes in 6 (13%) of 46 patients. Some eyes with OCT-proven cystoid macular edema did not show dye pooling in the fluorescein angiogram. The width of the total area of cystoid lesions was positively correlated with best-corrected visual acuity but the thickness of the neurosensory retina at the center of the fovea was not. OCT findings of successfully repaired macular holes were categorized into 3 groups. Eyes with U-type showed a normal foveal contour and a dark layer corresponding to the outer segment of photoreceptors. Eyes with V-type showed a notch in the surface of repaired neurosensory retina without a dark layer on the retinal pigment epithelium. Those with W-type showed a defect of the neurosensory retina, where the retinal pigment epithelium was exposed. The visual results were excellent in eyes with U-type, but poor in those with W-type.     

Kinetic and static fixation methods in automated threshold perimetry.

PURPOSE: Static fixation is the standard method for stabilizing the eye during automated perimetry. Kinetic fixation is an alternative for fixation control in which the eye follows a moving target. This study was conducted to evaluate the fixation accuracy of static and kinetic fixation perimetry and to determine their ability to detect the absolute scotoma of the physiologic blind spot. METHODS: The 71 patients with early glaucomatous field loss (mean age 65 years) and 45 control subjects (mean age 57 years) recruited from five clinical sites underwent threshold testing on the Dicon perimeter (kinetic fixation; Vismed, San Diego, CA) and Humphrey Field Analyzer (static fixation). The frequency of Heijl-Krakau fixation catch-trial errors was used as an indicator of fixation accuracy, and the measured sensitivity at the physiologic blind spot was used as an indicator of perimetric accuracy. RESULTS: In patients with glaucoma, the frequency of fixation errors was significantly greater for kinetic fixation (17.2%) than for static fixation (10.2%). In the control group, the frequency of fixation errors also was significantly greater for kinetic fixation (27.5%) than for static fixation (12.6%). The threshold at the presumed location of the blind spot (15 degrees temporal, 3 degrees inferior from fixation) was 14.8 dB using kinetic fixation versus 4.0 dB with static fixation in patients with glaucoma, and 18.5 dB using kinetic fixation versus 2.5 dB using static fixation in the control group. CONCLUSION: Relative to static fixation, kinetic fixation was associated with fixation inaccuracy and underestimation of the absolute scotoma at the physiologic blind spot.     

Feasibility and outcome of automated kinetic perimetry in children

Purpose  

Visual field testing in children is often performed using a Goldmann perimeter. Because the technique is performed manually, it is difficult to standardize, and stimuli are often presented too quickly. Automated kinetic perimetry has been successfully established in adults, but to date no results have been published in children. This paper describes the feasibility and outcome of automated kinetic perimetry in children in a standard clinical setting.     

The influence of the learning effect on automated perimetry in patients with suspected glaucoma

The influence of the learning effect on the outcome of automated perimetry was studied as a function of eccentricity. The same comprised 20 patients with suspected glaucoma who were all naive to automated perimetry. Visual field examination of the right eye followed by that of the left eye was undertaken on each of three successive days and after a further interval of 12 days using a customized full-field program of the Humphrey Field Analyser 630 (stimulus size III). The program comprised 60 points out to an eccentricity of 60 degrees with an interstimulus grid of 12 degrees. Global, central, peripheral, superior and inferior mean sensitivity each significantly increased (P less than or equal to 0.01) from the first to the second right eye examinations and from the third to the fourth left eye examinations (P less than or equal to 0.01). The global short-term fluctuation, central mean defect and number of stimulus presentations decreased from the first to the second right eye examination (P 0.01). The order of examination between eyes and the interval between examination sessions influences the response recorded by automated perimetry.     

The influence of stimulus parameters on the visual field indices by automated projection perimetry

The various stimulus parameters offered by two standard automated projection perimeters [Humphrey Field Analyser 630 (HFA) and Octopus 2011, namely, stimulus size and location and the interaction of adaptation level and stimulus duration, were compared in a sample of 20 patients attending a glaucoma clinic using the visual field indices mean defect (MD), loss variance (LV), short-term fluctuation (SF) and corrected loss variance (CLV). LV and SF were greater with Octopus program 32 compared with Octopus program G1 (P < 0.02). No difference in the indices was found between stimulus sizes I and III for HFA program 30-2. MD was greater for program 30-2 compared with program 32 (P < 0.002) when expressed in terms of log (L/L) whereas LV (P < 0.02) and SF (P < 0.02) were greater for program 32. All differences were considered to be negligible in the clinical sense.     

The effect of learning and age on short-term fluctuation and mean sensitivity of automated static perimetry

Knowledge of the effect of perimetric experience is essential in evaluation of visual fields. In the present study we report on the learning effect on short-term fluctuation (SF), and mean sensitivity (MS) correlating this effect with age in the older age groups. A sample of 33 volunteers with no history of ocular disease was subjected to two automated static perimetry tests. Program 32 of the Octopus 2000 was used for evaluation of the learning effect on SF and MS of the whole field, single quadrants and three eccentric zones. The learning effect on MS of the whole field and single zones of the first and the second session was statistically significant except in the upper temporal zone. Further, the learning effect showed a positive correlation with age on MS of the whole field, the lower quadrants and the eccentric zones from 0 to 20 degrees. The SF showed a significant learning effect, but no correlation with age could be demonstrated. However, SF increased significantly with age.