Determination of the normal range of exophthalmometric values for black and white adults

We used the Hertel exophthalmometer to measure the degree of protrusion in 681 adults, ranging in age from 18 to 91 years. The 327 white and 354 black subjects had no history of orbital or endocrine disease, severe myopia (more than -7 diopters), or buphthalmos. The mean normal protrusion values were 16.5 mm in white men, 18.5 mm in black men, 15.4 mm in white women, and 17.8 mm in black women. Although protrusion values above 21 mm are usually considered abnormal, we found that the upper limits of normal were 21.7 mm for white men, 24.7 mm for black men, 20.1 mm for white women, and 23.0 mm for black women. These differences were statistically significant (P less than .025). No individual had more than 2 mm of asymmetry between eyes.     

Normal values for Octopus tendency oriented perimetry in children 7 through 13 years old

Background The purpose of this study was to determine age-dependent values for mean sensitivity, mean deviation, and loss variance for normal children age 6 through 13 years, using the Octopus 301 perimeter and the Tendency Oriented Perimetry 32 (TOP-32) program.Methods Healthy children from 6 through 13 years of age with a visual acuity of 20/20 OU and at least 60 arc seconds of stereopsis were recruited. They were tested on the Octopus 301 perimeter using the TOP-32 program, and each eye was tested twice during one session. Results for all four tests were averaged for each subject, and the average was used for statistical analysis. The main outcome measures were mean sensitivity, mean deviation, and loss variance by age. The test duration, learning and fatigue effects, and the influence of false positive responses on the average mean sensitivity were also analyzed.Results There were 142 subjects tested. Six-year-old children showed high intersubject variability and were excluded (N=23). The average age of the remaining 7- to 13-year-old cohort (N=119) was 9.8 ± 1.7 years. The average test duration was 2.9 ± 0.3 min. The average mean sensitivity was 28.7 ± 1.9 dB. The mean sensitivities for tests 1 through 4 were 28.14, 28.63, 28.96, and 28.92 dB, respectively. The average mean deviation was 0.4 ± 1.9 dB. The slope of the regression line for mean sensitivity vs age was –0.018 ± 0.165 dB/year, which was not significantly different from zero (two-tailed t test, p=0.83). The false positive catch trial rate was high (mean 26%) and was independent of age. When the data from subjects who had more than two false positive catch trial responses on any one test were eliminated, the mean sensitivity decreased to 28.3 ± 1.9 dB.Conclusions When testing patients age 7 through 13 years on the Octopus 301 perimeter using the TOP-32 program, comparison against the programmed normal mean sensitivity value for 20-year-old subjects (29.0 dB) is appropriate. During a sequence of four tests, both learning and fatigue effects are evident. The false positive response rate is naturally high regardless of age, and children should not be overencouraged to respond during testing.This study was supported by a grant from Interzeag AG, Berne, Switzerland, to the Occidental Pediatric Eye Research Fund. Mr Monhart is employed by Interzeag. No other author has a financial relationship with Interzeag. The authors have full control over the primary data and agree to allow the Journal to review the data if requested.     

Normal values in the Aulhorn flicker test

In this paper the results of the Aulhorn flicker test in 105 healthy subjects are described. With decreasing flicker frequencies there was an increasing sensitivity to brightness below the individual flicker fusion frequency. These results contrast with those obtained in patients with acute optic neuritis. In these patients the sensitivity to brightness decreased at low flicker frequencies. The range of frequency intervals between 3 and 50 Hz in which the maximum increase in brightness sensitivity was be observed was also investigated. The results have been compiled in a diagram for clinical use.     

Normal values of short-wavelength automated perimetry

BACKGROUND: The purpose of this study was to evaluate short-wavelength automated perimetry (SWAP, i.e., blue-yellow) in normal volunteers and to review the current normal values provided by the manufacturer. METHODS: 28 eyes of 28 normal subjects (age range 21-48 years, mean age 36.5 years) had SWAP (Octopus 101, two phases of program G2, Interzeag AG, Schlieren, Switzerland). All subjects had normal eye examinations, refractive errors with spherical equivalents <5 diopters and astigmatism <2 diopters, normal intraocular pressures, no history of diseases affecting the visual field or nerve fiber layer, and normal white-white automated perimetry (Octopus 101, program G2). RESULTS: 21% of the subjects (6/28) had to be excluded since visual field testing was not reliable (reliability factor >5%). With the normal values provided by the manufacturer, only 45% of the remaining subjects (10/22) had all other indices within normal limits. With the appropriate normal values based on the multicenter SWAP Octopus 101 study, 11% (3/28) were beyond the normal range: all had abnormal high sensitivities - 2 due to false-positive response. The normal value range for the index Mean Defect is remarkably wide (5.-, median, 95.- percentile: -4.4, -0.5, +5.3 dB, respectively). The normal value range for the index Loss Variance is surprisingly low and similar to standard perimetry (5.-, median, 95.- percentile: -1.7, 6.8, +21.2 dB(2), respectively). CONCLUSION: SWAP with the Octopus G2 program reaches appropriate specificity but only if the correct normal values of the multicenter SWAP Octopus 101 study are used. The variability between subjects is remarkably large. The variability within a visual field is similar for SWAP and standard perimetry as reflected by similar values for the visual field index Loss Variance. Further studies have to establish the sensitivity to detect a disease for SWAP on the Octopus 101.     

国人蓝黄视野正常值检测

目的通过蓝黄视野检查法(blue-onyellowperimetry,B/YP)检测正常人蓝黄视野,以期确定国人蓝黄视野的正常参考值。方法应用OCTOPUS101全自动视野计(In-terzegINC,Switzerland)G2程序的Normal分程序进行B/YP视野检查,测定健康者180例360眼(10-70岁,每10岁为1个年龄段,分6个年龄段,每个年龄段男女各15例)蓝黄视野,将中心30°内全视网膜光敏感度均值(MS)及各象限光敏感度均值(dB值)分年龄段、性别及眼别分别进行比较和分析,并计算各年龄段全视网膜光敏感度均值的95%可信区间(CI)。结果B/YP检测正常人全视网膜光敏感度均值随年龄增加而降低,平均每10a降低1.2737dB。10-20岁为26.7833dB±2.7582dB(95%CI为26.0708-27.4959dB);21-30岁为25.7567dB±1.8101dB(95%CI为25.2891-26.2243dB):31-40岁为24.1133dB±2.7807dB(95%CI为23.3950-24.8317dB);41-50岁为22.7500dB±2.9662dB,(95%CI为211.9838-23.5162dB):51-60岁为21.1300(dB±2.4246dB(95%(CI为20.5037-21.7563(dB);61-70岁为20.4150dB±2.6847dB(95%(CI为19.7215-21.1085dB)。各年龄段内比较,下方视网膜光敏感度均值高于上方视网膜光敏感度均值,差异具有非常显著意义(P≤0.001)。不同性别、眼别视网膜光敏感度均值比较,差异无统计学意义。结论B/YP检测正常     

Normal values for the Pelli-Robson contrast sensitivity test

PURPOSE: To define normal values for the Pelli-Robson contrast sensitivity test in different age groups. SETTING: University Eye Clinic of Kuopio, Kuopio, Finland. METHODS: Contrast sensitivity was measured with the Pelli-Robson contrast sensitivity test in 87 persons (60 women and 27 men) with a mean age of 34.5 years +/- 20.8 (SD) (range 6 to 75 years). Results were studied by age group (years): 6 to 9, 10 to 19, 20 to 29, 30 to 39, 40 to 49, 50 to 59, and 60 and older. Of 163 eyes, both were healthy in 76 persons and 1 was healthy in 11. Study participants consisted of members of the staff of the Kuopio University Hospital Eye Clinic, medical students at the Kuopio University, and patients of the Strabismus and General Ophthalmology Units of the Eye Clinic and their accompanying persons. Two test distances were used: 1 m and 3 m. Eyes were tested individually; thereafter, the test was done binocularly. RESULTS: There were significant differences in logarithmic contrast sensitivity values among the age groups except on the test of the left eye at 1 m. The P values for the right eye at 1 m and 3 m, left eye at 1 m and 3 m, and both eyes at 1 m and 3 m were 0.003, 0.002, 0.19, 0.043, 0.037, and 0.003, respectively. The mean test results in 1 eye varied from 1.68 in the 60 year and older group to 1.84 in the 20 to 29 and 30 to 39 year groups. Binocularly, the variation was from 1.73 in the 40 year group to 1.99 in the 30 year group. CONCLUSIONS: The Pelli-Robson contrast sensitivity test is a quick and reliable method in a clinical setting. Normal values of the test can be of help in evaluating cataract patients or patients having refractive surgery.     

Normal range of exophthalmos values on orbit computerized tomography in Koreans

The value of parameters in Hertel's exophthalmometry was measured by using orbit computerized tomography (CT) in this study. We selected images that revealed the center of the lens, the largest eyeball contour and the optic canal on the axial view of orbit CT. Parameters of exophthalmometry on orbit CT were the distance between the lateral orbital rims of both eyes (A), the shortest distance from the corneal center to line A (B), the B/A ratio, the distance between the lateral orbital rim and the medial orbital rim (C), the length of the line passing through the lens center from the apex to line C (D) and the D/C ratio. To compare the center position of the eye, we measure the axial length (E) and the longest distance between the corneal apex and the posterior pole (F) which is parallel to line B. We also calculated B-F/2 and Hertel-F/2 in order to know if there is a difference between measurements of orbit CT and of Hertel's exophthalmometer. Subjects were classified into group 1 (aged 8-13 years old) and group 2 (aged 20 years old more). Sixteen subjects were enrolled in group 1 (32 eyes). In group 2, 100 subjects were male (200 eyes) and 35 were female (70 eyes). In group 1, the mean value was 89.94 mm for A, 13.49 mm for B, 35.13 mm for C, 10.64 mm for D, 24.40 mm for E, 24.20 mm for F, 0.15 for the B/A ratio and 0.30 for the D/C ratio. In group 2, the mean value was 100.93 mm for A, 15.03 mm for B, 38.78 mm for C, 12.03 mm for D, 24.62 mm for E, 24.33 mm for F, 0.15 for the B/A ratio and 0.31 for the D/C ratio. There was a statistically significant difference between the two groups for parameters A, B, C and D (p = 0.001), but no significant difference for the B/A (p = 0.239) and D/C ratios (p = 0.803). In the males and females of group 2, there was a statistically significant difference for the B/A ratio (p = 0.028). We suggest that the value of the D/C ratio (0.30-0.31) could be used as the index of protrusion. The normal values of exophthalmometry parameters measured by orbit CT could also be helpful to evaluate the exact protrusion in orbital diseases.     

Normal exophthalmometry values: the need for calibrated exophthalmometers

Visual loss is a devastating complication after orbital surgery, particularly that at the orbital apex or alongside the optic nerve. The clinical characteristics of 14 such patients, representing less than 1% of orbital surgery performed, are presented and the possible mechanisms discussed. The majority of patients suffered a posterior ischaemic optic neuropathy and this is likely to be related to postoperative vasospasm induced by extravasated blood and inflammatory mediators.     

Normal values for photopic and mesopic letter contrast sensitivity

PURPOSE: The exponential increase of patients having refractive surgery has increased the number of patients with night vision disturbances, such as decreased contrast sensitivity. However, there are no standard contrast sensitivity scales in normal persons in the mesopic range. We describe Pelli-Robson contrast sensitivity under photopic and mesopic luminance conditions in a large Spanish population over a wide range of age groups to provide normal values. A further aim was to evaluate the effect of photopic visual acuity on photopic and mesopic contrast sensitivity. METHODS: A cross-sectional study was performed on 292 participants stratified by age into six groups. Binocular contrast sensitivity was determined with best spectacle correction using the Pelli-Robson letter chart at 1 m under photopic (85 cd/m2) and mesopic (0.15 cd/m2) luminance conditions. RESULTS: Phototopic letter contrast sensitivity began to decrease gradually from the 61 to 70-year-old age group onward, and for mesopic conditions, from the 51 to 60-year-old age group onward. The reduction in mean contrast sensitivity between the oldest and the youngest age groups was 0.20 log units (photopic) and 0.33 log units (mesopic). Loss in contrast sensitivity due to luminance (two successive triplets) increased slightly with age. Both photopic and mesopic letter contrast sensitivity significantly improved as photopic visual acuity increased. CONCLUSIONS: Under mesopic conditions, Pelli-Robson contrast sensitivity began to decline 1 decade earlier than under photopic conditions and was affected by visual acuity. Normal values for mesopic contrast sensitivity could be of help in deciding whether mesopic function is normal or a decrease in contrast sensitivity is pathologic in nature.     

Normal values for a clinical test of letter-recognition contrast thresholds

PURPOSE: To investigate the contrast thresholds (CTs) in normal subjects using a high-luminance, letter-recognition task under clinically relevant testing conditions. SETTING: Texas Tech University Health Sciences System, Lubbock, Texas, USA. METHODS: Sixty normal subjects aged 20 to 49 years with a best corrected visual acuity of 20/20 or better in both eyes participated. M & S Technologies software was used to display black-on-white Sloan letters at contrast levels of 25%, 20%, 15%, 12%, and 10% through 1% in 1% decrements. The effects of age, sex, optotype size, eye dominance, ambient illumination level (bright = 625 - 630 lux; dim = <3 lux), and direction of approach to threshold were analyzed using a multivariate, ordinary, least-squares analysis. RESULTS: Age and sex did not influence CTs. Ascending versus descending testing was not statistically significant (P>.5). The effects of room illumination and eye dominance were significant (P<.01). Significant differences were found between 20/30 and 20/50, 20/30 and 20/70, and 20/50 and 20/70 optotype sizes (P<.01 for all comparisons). CONCLUSIONS: A commercially available, computer-based test of CTs was easy to administer and apparently easy for inexperienced subjects to perform. The results suggest criteria for detecting visual problems concerned with familiar but complex spatial-image shapes. This information might be used to assess the effects of treatments such as laser refractive surgery on recognition contrast. Further study is warranted.     

Normal values for the Octopus and their importance in the interpretation of findings

The relationship between loss of sensitivity to differences in light and advancing age is linear. The loss is greater in the upper and nasal halves of the visual field. There is always some scatter of measurements. Minor deviations from normal values are of no significance. If visual field findings are equivocal the patient should be followed up.     

Normal EOG values in intraretinal metastasis from cutaneous melanoma: a case report

Purpose: The electro-oculogram (EOG) is a powerful test to diagnose primary and metastatic choroidal tumors. While in benign tumors light-peak to dark-trough ratio values are in the range of normal subjects, these values appear highly altered in eyes affected by malignant choroidal tumors. Here we report a clinical case of a patient with intraretinal metastasis from cutaneous melanoma; notwithstanding the malignancy of the tumor, the EOG doesn't present alterations. Methods and results: Standard electro-oculographic recordings were performed before and after local excision of the tumor; recordings from the normal eye were taken as control. The EOG values were always normal in both eyes. Histological sections showed no evident change in the cell population of the retinal pigment epithelium (RPE) and Bruch's membrane. Conclusion: Our results suggest that the presence of an intact RPE is a crucial requirement to obtain a normal EOG. This revised version was published online in July 2006 with corrections to the Cover Date.     

Frisby Davis distance stereoacuity values in visually normal children

AIMS: To establish the range of normal distance stereoacuity in young children using the Frisby Davis distance stereo test (FD2). METHODS: Children passing preschool vision screening assessments underwent measurement of distance stereoacuity with the FD2 using a standard testing protocol. RESULTS: 59 visually normal children aged between 36 months and 68 months were recruited to this study. All 59 were able to understand the test requirements and were examined with the FD2 stereo test. Four (6.8%) had no measurable stereoacuity; 13 (24%) had stereoacuity measurable only at a 3 metre testing distance (mean 92.3 seconds of arc; SD 52.6). These children were significantly younger than the remaining 42 (76%) who demonstrated a stereoacuity response at a 6 metre testing distance (mean 29.6 seconds of arc; SD 13.1, p=0.008). CONCLUSION: The FD2 stereo test enables the measurement of distance stereoacuity in young children. There appears to be a maturational effect with distance stereoacuity improving between 36 months and 68 months. The data on age related normal values will provide a baseline from which to compare outcomes in clinical populations.     

Normal values of eye position in the Chinese population of Hong Kong.

Exophthalmos, interpupillary distance (IPD), interobital distance (IOD), and inner intercanthal distance (ICD) were measured in an adult Chinese population from Hong Kong (HKC). Mean values and normal range for 95% of the population were determined and the relation with head size and body height examined. Values of exophthalmos and IPD in our Chinese population were similar to those given for Caucasian groups. IOD and ICD were larger in the Chinese than in adult Caucasians. Our findings show generally larger values in the HKC than has been found for other populations in mainland China.