Monocular optokinetic nystagmus in humans with age-related maculopathy

AIM—To investigate full field monocular optokinetic nystagmus (OKN) in patients with age-related maculopathy (ARM) and relative central scotoma.
METHODS—Six patients aged 59-88 years with bilateral ARM and an aged-matched control group of six patients aged 54-83 years were examined. Visual fields were assessed with a Humphrey field analyser using the threshold 30-1 routine. Monocular full field horizontal optokinetic stimuli were presented on a hemicylindrical screen subtending 172° horizontally and 50° vertically. The stimulus was a projected random dot pattern and three stimulus velocities were used, 30, 50, and 70°/s in both nasalward and temporalward directions. Each trial lasted between 30 and 40 seconds and eye movements were monitored using infrared oculography.
RESULTS—The ARM patients had relative central scotomas with an average depth of 10 dB. Neither the ARM nor the age-matched groups displayed any directional preponderance or a buildup of the slow phase eye velocity with time. No statistically significant difference in the gain was found between the two groups (p>0.05).
CONCLUSIONS—Marked central field loss in ARM does not significantly impair OKN gain. This supports the view that complete central retinal integrity is by no means essential and that the peripheral retina provides an important input to the generation of OKN.

     

Modified Bagolini striated glass test: clinical applications of starlight test in binocular visual field screening

AIM—To introduce the "starlight" test which was devised to check binocular vision in normal conditions of seeing in a rapid, easy, and cost effective manner and to estimate the possibility of its clinical use in screening the binocular visual field of patients.
METHOD—The Bagolini striated glass test consists of optically plano lenses with imperceptible parallel scratches that barely blur the environment but produce two perpendicular luminous stripes (right eye stripe of 45° and left eye stripe of 135°) when subjects with normal binocular vision view one light source. Unlike the original Bagolini test, the starlight test uses three light sources in horizontal or vertical lines according to the testing purposes and the subject is asked to fixate upon the centre light. Through Bagolini glasses, the subject observes the resulting grid-like pattern and the state of binocular visual field of the subject can be roughly estimated.
RESULTS—Normal subjects and patients with strabismus, visual field loss from intracranial diseases, glaucoma, retinitis pigmentosa, and functional visual loss were examined using the starlight test and findings from each case were discussed.
CONCLUSIONS—The starlight test, which was made by hand at a low cost, is a simple test that can be used clinically. It provides information about the state of binocular vision of patients in normal conditions of seeing. It is also useful because it enables the examiner to share similar experiences with the examinee. The results suggest it can be effective in visual field screening.

Keywords: Bagolini striated glass; binocular visual field; screening; starlight test     

Visual outcome after paediatric cataract surgery: is age a major factor?

AIMS—To determine functional results after unilateral and bilateral cataract surgery in children with different aphakic optical correction.
METHODS—In this retrospective study, we evaluated visual acuity and binocular vision in 107 children who underwent cataract surgery during the 10 year period from 1985 to 1995. Aphakia was corrected by an intracapsular intraocular lens (IOL), spectacles or contact lenses.
RESULTS—Mean visual acuity was >20/40 (<0.3 log MAR) with normal binocular vision in 58 children over 7 months of age operated on for bilateral cataracts. Pseudophakic eyes regained visual acuity >20/63 (<0.5 log MAR) more often (90%) than aphakic eyes (46%) (p<0.001). Binocular vision was also achieved more often after IOL implantation (p<0.001). Visual outcome of early bilateral cataracts was less satisfactory in children with abnormal foveolar function. For 49 children who had surgery for unilateral cataracts, prognosis was poor when surgery was performed before the age of 7 months. For cataract surgery in older children (7 months) mean visual acuities were better with IOL implantation (p<0.05).
CONCLUSION—Cataract surgery with unilateral and bilateral IOL implantation can provide a beneficial effect on final visual outcome in children who are operated on before abnormal foveolar function develops.

Keywords: binocular vision; intraocular lens; paediatric cataract; visual outcome     

Use of scanning laser ophthalmoscopy to monitor papilloedema in idiopathic intracranial hypertension

AIMS—To determine the sensitivity of confocal scanning laser ophthalmoscopy (SLO) in detecting clinically significant changes in papilloedema secondary to idiopathic intracranial hypertension (IIH) and the correlation with visual field loss.
METHODS—Eight patients—three new, two recurrent, and three chronic cases of IIH—were examined over a 9 month period with SLO (Heidelberg retina tomograph) of optic nerve head and 30-2 Humphrey visual fields (six cases). Optic disc swelling (volume) was assessed in each eye using a circular contour line placed around the swollen optic nerve head on the mean image of three topographic images. Nine volume measurements from single images in each eye of every patient were performed on one occasion to assess repeatability.
RESULTS—In the five acute cases optic disc volumes (range 1-16 mm³) decreased with treatment to stable, normal levels. Three of these had mild, reproducible, field defects which resolved. Two chronic cases had stable or fluctuating disc volume with no detectable change in grade of papilloedema and mild field loss. In one case which underwent theco-peritoneal shunting both disc volume and field worsened, indicating therapeutic failure. Both improved postoperatively.
CONCLUSIONS—SLO has a high sensitivity for detecting small changes in disc volumes and correlates closely with visual field change in the short term. It can confirm therapeutic failure by detecting stable or increasing disc volume. Decreasing volume may indicate resolution of papilloedema or secondary optic atrophy, so accompanying funduscopy and visual fields remain essential.

Keywords: intracranial hypertension; scanning laser ophthalmoscopy; visual field; optic disc     

Integrated visual fields: a new approach to measuring the binocular field of view and visual disability

Background We have developed a method of quantifying the central binocular visual field by merging results from monocular fields (Integrated visual field). This study aims to compare the new measure with the binocular Esterman visual field test in identifying patients with self-reported visual disability.Methods Forty-eight patients with glaucoma each recorded Humphrey 24-2 fields for both eyes and an Esterman on the same day, and each completed a binary forced-choice questionnaire relating to perceived visual disability. Computer software merged sensitivity values from monocular fields to generate an integrated visual field and a related score of the number of defects at the <10 dB and <20 dB level. Receiver operating characteristic (ROC) analysis was used to compare the integrated visual field score and the Esterman disability score with individual responses to the questions on perceived difficulty with visual tasks.Results Comparison of areas under ROC curves revealed that a score based on the integrated visual field was generally better (median area: 0.79) than Esterman scores (median area: 0.70) in classifying patients with or without a self-reported perceived difficulty with visual tasks.Conclusions The integrated visual field offers a rapid assessment of a glaucoma patients binocular visual field without extra perimetric testing. As compared to an actual binocular field test (Esterman), the integrated visual field provides a better prediction of a glaucoma patients perceived inability to perform certain visual tasks.     

Early detection of visual field progression in glaucoma: a comparison of PROGRESSOR and STATPAC 2

AIM—To compare the performance of PROGRESSOR (pointwise linear regression) and STATPAC 2 (comparison with baseline values) in detecting early deterioration in the visual fields of glaucoma patients.
METHODS—Visual field series from 19 untreated normal tension glaucoma eyes which were deteriorating on clinical grounds were analysed by PROGRESSOR and STATPAC 2. Progression criteria for PROGRESSOR were (1) inner points: slope < −1 dB/year, p < 0.05 and (2) edge points: slope < −2 dB/year, p < 0.05. Criteria for STATPAC 2 were p < 0.05 change probability for any point on three consecutive fields. Detection time was defined as the time interval between the initial field and the first field in which at least one progressing point was identified. Detection times produced by the two techniques were compared.
RESULTS—PROGRESSOR and STATPAC 2 agreed on progression in all 19 eyes. Mean detection time for PROGRESSOR was 1.077 (SD 0.985) years and for STATPAC 2 was 2.161 (1.357) years. PROGRESSOR detected progression sooner than STATPAC 2 in 18 eyes (p < 0.01, Wilcoxon matched pairs signed rank test). PROGRESSOR detected progression earlier by a mean of 1.085 (0.936) years.
CONCLUSIONS—PROGRESSOR consistently detected progression earlier than STATPAC 2. The PROGRESSOR software is a useful tool for the early detection of visual field deterioration in glaucoma.

     

Use of subjective and objective criteria to categorise visual disability

Context:

Visual disability is categorised using objective criteria. Subjective measures are not considered.

Aim:

To use subjective criteria along with objective ones to categorise visual disability.

Settings and Design:

Ophthalmology out-patient department; teaching hospital; observational study.

Material and Methods:

Consecutive persons aged >25 years, with vision <20/20 (in one or both eyes) due to chronic conditions, like cataract and refractive errors, were categorized into 11 groups of increasing disability; group-zero: normal range of vision, to group-X: no perception of light, bilaterally. Snellen''s vision; binocular contrast sensitivity (Pelli-Robson chart); automated binocular visual field (Humphrey; Esterman test); and vision-related quality of life (Indian Visual Function Questionnaire-33; IND-VFQ33) were recorded.

Statistical Analysis:

SPSS version-17; Kruskal-wallis test was used to compare contrast sensitivity and visual fields across groups, and Mann-Whitney U test for pair-wise comparison (Bonferroni adjustment; P < 0.01). One-way ANOVA compared quality of life data across groups; for pairwise significance, Dunnett T3 test was applied.

Results:

In 226 patients, contrast sensitivity and visual fields were comparable for differing disability grades except when disability was severe (P < 0.001), or moderately severe (P < 0.01). Individual scales of IND-VFQ33 were also mostly comparable; however, global scores showed a distinct pattern, being different for some disability grades but comparable for groups III (78.51 ± 6.86) and IV (82.64 ± 5.80), and groups IV and V (77.23 ± 3.22); these were merged to generate group 345; similarly, global scores were comparable for adjacent groups V and VI (72.53 ± 6.77), VI and VII (74.46 ± 4.32), and VII and VIII (69.12 ± 5.97); these were merged to generate group 5678; thereafter, contrast sensitivity and global and individual IND-VFQ33 scores could differentiate between different grades of disability in the five new groups.

Conclusions:

Subjective criteria made it possible to objectively reclassify visual disability. Visual disability grades could be redefined to accommodate all from zero-100%.     

Recovery in microtropia: implications for aetiology and neurophysiology

AIMS/BACKGROUND—The basis of binocular single vision in microtropia remains a matter of contention. This paper discusses the implications of recovery, in a group of primary microtropes following treatment, in relation to current concepts on the aetiology of the condition and proposed retinocortical correspondence.
METHODS—Nine previously untreated primary microtropes whose condition resolved, were reviewed in detail to assess the patterns of change in retinal correspondence, uniocular fixation, stereoacuity, and visual acuity in response to treatment.
RESULTS—Anomalous retinal correspondence (ARC), a central scotoma, reduced or absent stereoacuity, amblyopia, and uniocular eccentric fixation were present in all patients before treatment. Following treatment, all cases attained normal retinal correspondence (NRC), elimination of the central scotoma, stereo acuity levels of between 20 and 40 seconds of arc, 6/5 Snellen visual acuity in both eyes, and foveal fixation in both eyes.
CONCLUSION—A hypothesis is put forward that for the patients described, a period of normal development is likely to have preceded the onset of microtropia, during which the retinocortical "foundations" for NRC were established. Precise pairing of foveo-foveal receptive fields was not abolished by the presence of amblyopia and a central scotoma, but this relation was temporarily suspended and binocular single vision was sustained via the neural substrate of paired receptive fields over a wide retinocortical area.

Keywords: anomalous retinal correspondence; stereoacuity; retinocortical connections     

Does raised intraocular pressure begin in utero?

AIM—To determine whether fetal and infant growth, as assessed by weight at birth and weight at 1 year, are related to intraocular pressure.
METHODS—717 men and women born in Hertfordshire between 1920 and 1930, for whom records of birth weight and weight at 1 year were available, were examined. Visual fields were assessed using the Takagi central 25 degree 75 point static threshold screening program. Tonometry was performed using the Perkin's tonometer. The disc was assessed by direct ophthalmoscopy through dilated pupils.
RESULTS—A significant inverse relation was found between systolic blood pressure and birth weight. However, no association was found between birth weight or weight at 1 year and intraocular pressure, cup/disc ratio, or visual field defects.
CONCLUSIONS—There was no evidence to support fetal or infant growth as being important factors for the subsequent development of raised intraocular pressure.

Keywords: birth weight; intraocular pressure; cup/disc ratio; visual field defects     

Blue-yellow colour vision in an onchocercal area of northern Nigeria

AIM—To determine if the City University Tritan Test is a useful addition to visual function assessment in rural communities in northern Nigeria.
METHODS—The study was a cross sectional survey. The participants were 8394 people, aged 5 years and over, living in 37 rural communities, mesoendemic and non-endemic for onchocerciasis, in Kaduna State in northern Nigeria. The main outcome measures were the detection of a defect in blue-yellow colour vision by two criteria: (1) failure with the City University tritan screening plates; (2) failure with the City University grading plates to identify severe tritan defects.
RESULTS—91% of those aged 10 years and above could perform the test. Below this age, there were difficulties in comprehension. The test showed good inter- and intraobserver agreement. After adjustment for confounders the odds of failing the screening plates were significantly increased in the presence of optic atrophy or glaucoma (3.55 (2.48-5.08) and 15.9 (4.22-60.2) respectively). There was a greater increase in the adjusted odds of failing the grading plates in the presence of optic atrophy or glaucoma (5.30 (2.97-9.45) and 8.87 (1.61-48.7) respectively). Cataract had a smaller effect on the screening plates, adjusted odds 1.63 (0.95-2.80).
CONCLUSION—Blue-yellow colour vision testing is a useful addition to visual function assessment in those aged 10 years and above in rural northern Nigeria, particularly in the detection of optic nerve disease.

Keywords: tritan defects; optic nerve disease; onchocerciasis; visual function assessment     

Pulsatile ocular blood flow investigation in asymmetric normal tension glaucoma and normal subjects

AIMS—This study was designed to investigate pulsatile ocular blood flow (POBF) in normal tension glaucoma (NTG) patients and in normal controls. NTG patients with unilateral field loss were evaluated to compare POBF values between eyes with and without field loss.
METHODS—POBF measurements from more than 1500 subjects were collected during a period of 6 months from six optometric centres. Subjects with systemic vascular diseases (such as systemic hypertension and diabetes), ophthalmic diseases, a positive family history of glaucoma, and those individuals receiving treatment with systemic β blockers were excluded on the basis of a questionnaire. For comparison, 95 NTG patients with unilateral field loss, selected from 403 consecutive patients with NTG, underwent POBF testing. For each individual age, sex, intraocular pressure, refraction, and pulse rate were entered into a database.
RESULTS—Data from 777 subjects were included in the analysis. POBF measurements of patients and subjects were compared allowing for differences in age, sex, intraocular pressure, refraction, and pulse rate. POBF was significantly lower in eyes of NTG patients with and without field loss (p <0.001 and p = 0.01 respectively). Eyes of NTG patients with field loss showed significantly lower POBF than the contralateral eyes with normal field (p < 0.001).
CONCLUSIONS—POBF was significantly lower in eyes of NTG patients with and without field loss than in normal subjects, suggesting that differences in ocular blood perfusion are relevant to the development of NTG and are detectable from the early stage of the disease. Furthermore, the finding of lower POBF in NTG eyes with field loss than in the contralateral eyes with normal field suggests that haemodynamic differences between fellow eyes contribute to determine the side of onset of the disease.

Keywords: pulsatile ocular blood flow; normal tension glaucoma; visual field asymmetry     

Visual functioning and quality of life outcomes among cataract operated and unoperated blind populations in Nepal

BACKGROUND—Visual acuity and vision related quality of life outcomes in cataract surgery were evaluated in a population based survey in two geographic zones in Nepal.
METHODS—Case finding was based on random sampling using a stratified cluster design with door to door enumeration of people aged 45 years followed by eye examinations at village sites. All aphakics/pseudophakics, those with visual acuity less than 6/60 in either eye, and a sample of those with normal visual acuity were administered visual functioning (VF) and quality of life (QOL) questionnaires.
RESULTS—15% of the 159 cataract operated cases had presenting visual acuity 6/18 in both eyes, 38% with best corrected visual acuity. 21% were still blind with presenting visual acuity <6/60 in both eyes, 7% with best correction. On a 0-100 scale, mean VF and QOL scores were 87.2 and 93.9 respectively in normally sighted unoperated individuals, dropping to 15.6 and 29.5 for those severely blind (<3/60). Among the cataract operated, mean VF and QOL scores were 47.5 and 55.4, respectively. VF and QOL scores correlated with vision status at statistically significant levels (p <0.0001)
CONCLUSION—Cataract surgery outcomes, whether measured by traditional visual acuity or by patient reported VF/QOL, are at levels many would consider unacceptably low. It is apparent that in the quest to reduce cataract blindness much more attention must be given to improving surgery outcomes.

Keywords: cataract surgery; visual acuity; visual functioning; quality of life     

BD8 certification of visually impaired people

BACKGROUND—There is debate as to the completeness of the blind and partial sight registers in England and Wales. The purpose of this study was to estimate the proportion of eligible visually impaired people attending the hospital eye service who have a BD8 certificate and to identify factors associated with not being certified.
METHODS—Cross sectional survey of patients attending outpatients by medical record review analysed by multiple logistic regression.
RESULTS—51% (43%, 58%) of patients identified as eligible for registration did not have a BD8 certificate. The severity of visual impairment and the main diagnosis in terms of requirements for treatment, permanence of visual loss, and visual field loss were independently associated with non-certification. A partially sighted patient is estimated to be three times more likely to not have a BD8 certificate as a blind patient of similar diagnosis (adj OR: 3.4 (95% CI: 1.7, 6.8)). A patient whose impairment is due to abnormal visual fields is estimated to be greater than three times more likely to be non-certified than one with low visual acuity of similar severity and cause (adj OR: 3.6 (95% CI: 1.0, 12.7)). People whose impairment is potentially reversible are estimated to be eight times ( 8.3 (2.2, 31.4)) more likely not to have a certificate compared with people who had permanent non-treatable visual loss; and in those with permanent visual loss, a requirement for ongoing treatment was found to be associated with a lower odds of certification.
CONCLUSIONS—These data strongly suggest that epidemiological data collected during registration are biased towards permanent, non-treatable causes of visual loss and those which affect central rather than peripheral vision. Certain subgroups of the visually impaired are likely to be at greater risk of non-certification. BD8 guidelines need to be simplified.

Keywords: registration; BD8 certification; data collection; visual impairment     

Visual behaviours of neurologically impaired children with cerebral visual impairment: an ethological study

BACKGROUND/AIMS—Visual functions of neurologically impaired children with permanent cerebral visual impairment (CVI) can be difficult to determine. This study investigated the behavioural profile of CVI children by means of ethological observations in order to gain a better understanding of their visual functions.
METHODS—Video registrations of nine subjects who were unable to undergo more orthodox methods of visual function testing were observed and analysed by an ethologist.
RESULTS—A series of behaviours (direct signs) and supportive or confirming behavioural elements (indirect signs) indicating some visual perception in the children were found.
CONCLUSION—Detailed ethological observations of visual behaviour were shown to be useful for analysing visual functions of children with permanent CVI.

Keywords: cerebral visual impairment; visual function; visual behaviour; ethological analysis     

High spatial resolution automated perimetry in glaucoma

BACKGROUND—Automated perimetry is of fundamental importance in assessing visual function in glaucoma. A technique was evaluated to perform high spatial resolution automated perimetry to allow a more detailed assessment of the luminance sensitivity in selected regions of the visual field than is possible with conventional perimetry.
METHOD—High spatial resolution perimetry was performed using a Humphrey automated perimeter by measuring luminance sensitivity across a 9 by 9 degree custom grid of 100 test locations with a separation between adjacent locations of 1 degree. Quantitative analysis of the raw and Gaussian filtered thresholds was performed to assess the repeatability of the technique in normals, glaucoma suspects, and glaucoma patients.
RESULTS—The testing protocol was well tolerated by all subjects. High spatial resolution perimetry in glaucomatous eyes demonstrated fine luminance sensitivity loss not suspected with conventional perimetry. High spatial resolution perimetry also demonstrated reproducible areas of sensitivity loss in some glaucomatous eyes in areas of the visual field which appear normal with conventional programmes. The repeatability of the technique correlated with mean threshold sensitivity and was substantially improved to clinically acceptable levels by Gaussian filtering the thresholds.
CONCLUSION—This technique of high spatial resolution perimetry allows the practical assessment of selected regions of the visual field at higher resolution than conventional perimetry, and may be clinically useful in glaucoma.

     

Improvements in clinical and functional vision and perceived visual disability after first and second eye cataract surgery

AIMS—To determine the improvements in clinical and functional vision and perceived visual disability after first and second eye cataract surgery.
METHODS—Clinical vision (monocular and binocular high and low contrast visual acuity, contrast sensitivity, and disability glare), functional vision (face identity and expression recognition, reading speed, word acuity, and mobility orientation), and perceived visual disability (Activities of Daily Vision Scale) were measured in 25 subjects before and after uncomplicated cataract surgery (10 first eye surgery and 15 second eye surgery) and in 10 age matched controls.
RESULTS—Significant improvements were found after surgery in clinical and functional vision and perceived visual disability. Greater improvements were found after first eye surgery than after second eye surgery. However, first eye surgery did not return all scores to age matched normal levels. There were significant improvements in several of the tests measured after second eye surgery, and all postoperative values were similar to those from age matched normals.
CONCLUSIONS—Significant improvements in clinical, functional, and perceived vision are obtained by cataract surgery. The improvements in objective measures of functional vision found in this study support previous findings of improvements in patients' perceived functional vision. In addition, these data provide support to the necessity of second eye surgery in some patients to improve certain aspects of visual function to age matched normal levels.

     

Intraocular pressure and central visual field of normal tension glaucoma

AIM—To study whether damage in the central 30° field of normal tension glaucoma (NTG) is relatively heterogeneous or homogeneous with respect to intraocular pressure (IOP) related damage.
METHODS—Using the results of Humphrey perimeter examinations, the central 30° field was divided into four subfields; superior and inferior hemifields excluding the caecocentral field (30-2 program) and superior and inferior 10° hemifields (10-2 program). In 103 NTG cases, the intraindividual bilateral difference in the mean of total deviations (mean TD) in the four subfields was analysed by multiple linear regression to correct the effects of factors other than IOP. Explanatory variables were the intraindividual bilateral difference in the mean of clinic IOP (IOP_mean), that in the ratio of area of peripapillary atrophy corresponding to each subfield to disc area, and that in myopic refraction.
RESULTS—The intraindividual bilateral difference in the mean TD was significantly and negatively correlated with that in IOP_mean in three of the above four subfields (p<0.005) and correlation tended to be negative (p=0.07) in the superior 10° hemifield.
CONCLUSIONS—Diffuse IOP related damage was suggested in the central 30° field of NTG; greater extent of the damage in the above four subfields was correlated with higher mean IOP. The present findings may have clinical implications.

     

Activated protein C resistance in patients with central retinal vein occlusion

AIM/BACKGROUND—A new defect in the anticoagulant system has recently been discovered—activated protein C resistance. The frequency of this disorder has been shown to be increased in young patients (<50 years of age) with central retinal vein occlusion. This study was carried out to determine if there was any overrepresentation of activated protein C resistance in patients >50 years of age with central retinal vein occlusion.
METHODS—Blood samples were obtained from 83 patients >50 years of age and with a history of central retinal vein occlusion. The blood samples were analysed for activated protein C resistance with standard clinical laboratory methods.
RESULTS—In this material 11% of the patients were resistant to activated protein C. The normal incidence of activated protein C resistance in the same geographical area is 10-11%.
CONCLUSION—Activated protein C resistance does not seem to be a cause of central retinal vein occlusion in people older than 50 years.

     

Difficulty in performing everyday activities in patients with juvenile macular dystrophies: comparison with patients with retinitis pigmentosa

AIMS—To ascertain the level of perceived difficulty experienced by patients with central vision loss due to juvenile macular dystrophies in the performance of everyday activities. A second objective was to compare their perceived difficulty with that of patients with retinitis pigmentosa (RP) with primarily peripheral vision loss.
METHODS—72 patients with Stargardt disease, cone dystrophy, or cone-rod dystrophy who had visual acuities worse than 20/40 and normal peripheral visual fields rated themselves on their difficulty in the performance of 33 activities encompassing a wide variety of everyday tasks. These findings were compared with the responses of 120 patients with typical RP or Usher syndrome type 2 who had visual acuities of 20/40 or better and peripheral visual field loss.
RESULTS—The juvenile macular dystrophy group reported the greatest level of overall self perceived difficulty with activities involving central vision, and lesser and variable degrees of difficulty with items within the mobility, negotiating steps, driving, and miscellaneous categories. Consistent with these findings, there were highly significant correlations between subjects' rated performances of activities involving central vision and the clinical measures of vision, including visual acuity and size of central scotoma. There were fewer significant correlations between perceived performance of activities in the other categories and the clinical measures. In general, those activities that showed significant correlations with the clinical measures of vision for the patients with juvenile macular dystrophies also showed significant differences in the patterns of responses between the juvenile macular dystrophy group and the RP group. Those items which were not correlated with the clinical measures in the juvenile macular dystrophy group tended not to show significant differences in the response patterns between the two groups.
CONCLUSION—These results provide insight into the types of perceived difficulties in performing tasks of everyday life in patients with these disorders which affect counselling of these patients.

Keywords: vision; impairment; everyday activities; juvenile macular dystrophy     

单眼视野损伤程度对青光眼患者双眼视野的影响

目的：探讨单眼视野丢失严重程度对原发性闭角型青光眼、原发性开角型青光眼和正常眼压性青光眼患者双眼视野缺损的影响。

方法：根据双眼单眼视野缺损的阶段,将120例青光眼患者和30例健康参与者分为正常、早期、中度或重度四个阶段。通过整合视野和Esterman双眼视野评估确定双眼视野。在组内和组间比较单眼和双眼视野参数。

结果：对于一只眼睛处于正常或早期阶段而另一只眼睛处于严重阶段的患者,双眼综合视野平均偏差分别为-2.8±1.1、-5.5±1.9dB,以及Esterman的平均得分分别为99.1%±1.7%和95.6%±4.7%。当双眼发展为中度或重度损伤(中度/中度,中度/重度或重度/重度)时,双眼综合视野平均偏差低于-6dB,中度/中度和中度/严重损伤组Esterman的平均得分分别为94.2%±6.0%、94.3%±4.9%,但当双眼处于重度损伤阶段时,Esterman的平均得分迅速从大于90%下降到68.4%±26.3%。

结论：如果一只眼睛处于正常或早期阶段,双眼视野可以保持相对完整。当双眼进展到中度或重度阶段时,通过双眼综合视野平均偏差测量的双眼视野缺损是显著的,并且仅当双眼进入严重阶段时才检测到显著的Esterman双眼视野缺损。