Automated perimetry detects visual field loss before manual Goldmann perimetry

Virtual reality headsets for perimetry testing: a systematic review

Standard automated perimetery is considered the gold standard for evaluating a patient's visual field. However, it is costly and requires a fixed testing environment. In response, perimetric devices using virtual reality (VR) headsets have emerged as an alternative way to measure visual fields in patients. This systematic review aims to characterize both novel and established VR headsets in the literature and explore their potential applications within visual field testing. A search was conducted using MEDLINE, Embase, CINAHL, and the Core Collection (Web of Science) for articles published until January 2023. Subject headings and keywords related to virtual reality and visual field were used to identify studies specific to this topic. Records were first screened by title/abstract and then by full text using predefined criteria. Data was extracted accordingly. A total of 2404 records were identified from the databases. After deduplication and the two levels of screening, 64 studies describing 36 VR headset perimetry devices were selected for extraction. These devices encompassed various visual field measurement techniques, including static and kinetic perimetry, with some offering vision rehabilitation capabilities. This review reveals a growing consensus that VR headset perimetry devices perform comparably to, or even better than, standard automated perimetry. They are better tolerated by patients in terms of gaze fixation, more cost-effective, and generally more accessible for patients with limited mobility.

Periphery kinetic perimetry: clinically feasible to complement central static perimetry

Background

Existing evidence suggests that visual field defect in eyes with glaucoma significantly varies between individuals. The following study compared the central visual field defects with the peripheral visual field defects in patients with suspect glaucoma and primary open-angle glaucoma (POAG) and investigated whether using the central visual field test alone could result in loss of clinically valuable information.

Methods

In this prospective observational study, 167 eyes from 89 patients with suspect glaucoma or POAG were first examined with static automated perimetry (SAP), followed by a peripheral visual field test on Octopus 900 perimeter (Haag-Streit, Koeniz, Switzerland). The peripheral visual field test was performed by “Auto Kinetic Perimetry” program, in which Goldmann III4e stimuli randomly moved along 16 vectors at a constant angular velocity of 5 deg/s.

Results

Glaucomatous peripheral visual field defects were seen in 18% of the eyes with a normal central visual field. In addition, 86% of glaucoma patients with moderate-to-severe central visual field defects had corresponding peripheral visual field defects in the form of localized or diffuse depression of the isopters. Furthermore, a moderate correlation was found between the central and peripheral visual fields. The median test duration was 71 s for the peripheral test and 803 s for the central test (p < 0.001).

Conclusions

Our study demonstrated the diversity of glaucomatous visual field defects, as well as the possibility of losing the clinically valuable information due to focusing on the central visual field test alone. The peripheral kinetic perimetry is clinically feasible to complement the central static perimetry for a comprehensive assessment of visual function in glaucoma patients.

New Strategies for Automated Perimetry: Historical Perspective and Future Innovations

How to cite this article: Groth SL. New Strategies for Automated Perimetry: Historical Perspective and Future Innovations. J Curr Glaucoma Pract 2021;15(3):103-105.

A Cross-Sectional and Longitudinal Study of Retinal Sensitivity in RPE65-Associated Leber Congenital Amaurosis

Purpose

RPE65-associated Leber congenital amaurosis (RPE65-LCA) is an early-onset severe retinal dystrophy associated with progressive visual field loss. Phase I/II and III gene therapy trials have identified improved retinal sensitivity but little is known about the natural history of retinal sensitivity in RPE65-LCA.

Methods

A total of 19 subjects (aged 9 to 23 years) undertook monocular full-field static perimetry of which 13 subjects were monitored longitudinally. Retinal sensitivity was measured as mean sensitivity (MS) and volumetrically quantified (in decibel-steradian) using visual field modeling and analysis software for the total (V_TOT), central 30° (V₃₀) and central 15° (V₁₅) visual field. Correlation was evaluated between retinal sensitivity and age, best-corrected visual acuity (BCVA), contrast sensitivity, vision-related quality of life, and genotype. Test-retest reliability was also investigated.

Results

V₃₀ was identified to have a strong, weak, and moderate correlation with age, BCVA and contrast sensitivity respectively. Furthermore, V₃₀ was identified as having a weak linear relationship with the mobility and independence domains of the vision-related quality of life questionnaire. Longitudinal analysis demonstrated a slow loss of retinal sensitivity in this cohort. Subjects with at least one RPE65 nonsense variant appeared to show greater progressive loss of retinal sensitivity in the second decade of life than those without.

Conclusions

Volumetric assessment of central 30° visual field sensitivity, V_30, is a useful independent measure of retinal function and, in our data, represented the best metric to monitor deterioration of retinal sensitivity in RPE65-LCA. Furthermore, functional correlation with genotype may enable more informed prognostic counseling. (ClinicalTrials.gov number, NCT02714816.)

Will Perimetry Be Performed to Monitor Glaucoma in 2025?

Visual field testing has played an essential role in the diagnosis and management of glaucoma for more than a century. Methods to examine the visual field have been refined from early kinetic perimetry to current standard automated perimetry (SAP). Clinicians now use SAP for the diagnosis and management of glaucoma throughout the world. Various testing paradigms and analytic methods have been developed to simplify the diagnosis of glaucoma and the interpretation of progression. Moreover, strategies have been implemented to improve patient experience with visual field testing and to increase reliability. Objective functional tests, such as electroretinography, provide an alternative to subjective visual field testing but are not yet ready for widespread adoption. Standard automated perimetry is being adapted and improved constantly. New devices may allow patients to complete visual field tests at home, which could relieve patients and clinicians from in-office testing and allow for more frequent examinations. Glaucoma detection and progression analysis also are incorporating progressively more information and will be improved as deep learning strategies are applied. Finally, perimetric and structural testing likely will become more closely intertwined as testing platforms and progression analysis incorporate both of these measures. Visual field testing will continue to have an important role in the diagnosis and management of glaucoma.

Pattern of Visual Field Loss in Primary Angle-Closure Glaucoma Across Different Severity Levels

PURPOSE

To investigate the patterns of visual field (VF) defects in primary angle-closure glaucoma (PACG) across different severity levels and to assess hemifield differences within each severity level.

DESIGN

Cross-sectional study.

PARTICIPANTS

Three hundred four patients diagnosed with PACG were recruited from glaucoma clinics at a Singapore hospital.

METHODS

Point-wise total deviation values were recorded from the static automated perimetry (Swedish interactive threshold algorithm standard program 24-2; Humphrey model 750 [Carl Zeiss Meditec, Dublin, CA]) printouts. Patients were excluded if they had unreliable VFs (fixation losses >33% and false-positive responses >15%), had undergone only 10-2 VF testing, had VF defects not typical of glaucoma, or had undergone cataract extraction. Mild, moderate, and severe VF loss were defined by a mean deviation of -6.00 dB or more, -6.01 to -12.00 dB, and -12.01 dB or less, respectively. Each hemifield was divided into regions according to glaucoma hemifield test sectors. The average mean deviation (MD) of each region was obtained using total deviation values.

MAIN OUTCOME MEASURES

Between- and within-hemifield differences of the regions across the severity levels.

RESULTS

After excluding ineligible cases, 249 patients with PACG were included in the analysis. Mean age of the patients was 65.7±8.6 years, with a 1:1 gender ratio. The number of patients who had mild, moderate, and severe VFs was 72 (28.9%), 78 (31.3%), and 99 (39.8%), respectively. For between-hemifield comparisons, all regions in the superior hemifield had worse MDs compared with their counterparts in the inferior hemifield across the severity spectrum. Likewise, for within-hemifield comparisons, MDs of the regions gradually worsened with increasing distance from the fixation point.

CONCLUSIONS

In this group of clinic-based PACG patients, the superior hemifield was found to be affected more severely than the inferior hemifield, and the differences between them increased with worsening disease severity. The damage was consistently more pronounced in the nasal area.

Spatial agreement between Goldmann visual field defects and fundus autofluorescence in patients with birdshot chorioretinopathy

BACKGROUND

The purpose of this paper is to study the spatial agreement between visual field defects and ultra-wide field (UWF) fundus autofluorescence (FAF) in patients with birdshot chorioretinopathy (BSCR). The study is a retrospective, cross-sectional analysis of a university uveitis practice. Eight (8) eyes of five (5) patients with BSCR were included. Inclusion criteria were ability to fixate reliably. Goldmann visual fields (GVF) and UWF FAF were obtained, digitalized, and standardized. Analysis was performed by measuring areas of overlap of hypo-autofluorescent FAF lesions and GVF scotomas within the central 60°. Overlap was calculated as a percentage of the total area of FAF and GVF, respectively. Average areas were also calculated.

RESULTS

The mean age of the subjects was 51 ± 12.28 years (range 38-69 years). 14 ± 23 % of the total lesion area identified as hypo-autofluorescent on FAF overlapped with scotoma. 28 ± 41 % of the GVF scotomas overlapped with hypo-autofluorescent FAF lesions. Average area of FAF hypo-autofluorescence was much larger (15.19 disc areas) than GVF (3.45 disc areas).

CONCLUSIONS

There appear to be larger total areas of hypo-autofluorescence on FAF than scotoma evidenced by GVF and only a small amount of overlap. The finding suggests that GVF is relatively insensitive to anatomic loss, which can be detected using FAF. Further studies are required to assess whether this finding holds true for automated white-on-white perimetry. In addition, more selective psychophysical stimuli may have higher sensitivity in detecting early functional loss that accompanies anatomic damage.

Ophthalmic markers of the diabetic polyneuropathy

In the article, a world literature analysis is presented on the relationship between structural and functional changes of the retina and of the optic nerve and the diabetic polyneuropathy severity degree. Diabetic polyneuropathy is one of the most common and severe complications of diabetes mellitus leading in many patients to ulcer formation and to foot amputation. Modern methods for neuropathy diagnosis either do not allow revealing early stage changes, or include invasive procedures. Ophthalmologists, involved in diabetic patients care, due to objective reasons focus on diabetic retinopathy. However, the evidence that the corneal nerves state is a marker of peripheral neuropathy suggests a new and very important role of the ophthalmologist in diabetic patient care. Several studies obtained promising results about structural and functional retinal changes could be found in diabetic patients before retinopathy start; this allows to suggest the neuropathy role at their origin.

Effect of Optical Defocus on the Kinetic Perimetry in Young Myopic Participants

PURPOSE

The prospective study evaluated the effects of optical defocus on kinetic sensitivity using automated kinetic perimetry.

MATERIALS AND METHODS

The 17 eyes of 17 healthy young participants were evaluated. All of the participants had myopia (≥ -5.00 D) and mild to no astigmatism (<1.00 D). Automated kinetic perimetry was performed using the Octopus 900 perimeter with Goldmann stimuli III4e, I4e, I3e, I2e, and I1e, with stimuli presented at 14 predetermined meridians, and a velocity of 3°/s. Optical defocus was induced with soft contact lenses, and varied in 1 D increments between 0 and +7 D. Kinetic sensitivity at each defocus was evaluated and compared to sensitivity with no defocus.

RESULTS

Although kinetic sensitivity with the III4e and I4e stimuli decreased slightly at the inferior nasal, total kinetic sensitivity measured with the III4e and I4e stimuli was unaffected by optical defocus. Conversely, kinetic sensitivity measured with the I3e, I2e, and I1e stimuli decreased at defocus greater than +6 D (p < 0.05), + 3 D (p < 0.01), and at a defocus greater than +1 D (p < 0.01), respectively.

CONCLUSIONS

Kinetic sensitivity was unaffected by defocus when measured with III4e and I4e stimuli. However, measurements with I3e, I2e, and I1e stimuli were affected, in particular measurements with I2e and I1e stimuli. Therefore, we conclude that optimal refractive correction with a contact lens or a spectacle lens is required in order to obtain accurate kinetic perimetry results, particularly for lower intensity stimuli.

Visual field findings after a ruptured intracranial aneurysm

BACKGROUND

Visual field defects (VFDs) negatively affect activities of daily living and rehabilitation following aneurysmal subarachnoid haemorrhage (aSAH). The aim here was to assess VFDs in patients with aSAH and their associations with age, gender, aSAH severity, and clinical outcome.

METHODS

Patients admitted to Helsinki University Central Hospital and treated during 2011 were participants in this prospective study. Findings obtained with the Octopus 900 perimeter (Haag-Streit Inc, Koenic, Switzerland), the Goldmann perimeter (Haag-Streit Inc, Bern, Switzerland), or the confrontation visual field test on admission and 3 days, 14 days, 2 to 4 months, and 6 months postoperatively were assigned to 16 classes. Associations between post-chiasmal VFDs and relevant clinical, radiological, and demographic data were analysed with uni- and multivariate logistic regression.

RESULTS

Of 105 survivors at 6 months, 20 (19 %) had VFDs occurring for aneurysm- or operation-related reasons; homonymous hemianopias or quadrantanopias were the most common finding, occurring in 16 patients (15 %). Posterior ischaemic optic neuropathy presented in two patients (2 %). Ten survivors (10 %) no longer fulfilled visual field requirements for driving licences. Significant associations emerged between VFDs at 6 months and the Hunt and Hess (H&H), World Federation of Neurosurgical Societies (WFNS), and Fisher grades on admission, presence of intracerebral haemorrhage (ICH), hydrocephalus, or postoperative infarction, and higher modified Rankin Scale scores at 6 months. Multivariate logistic regression showed the H&H grade and presence of ICH to independently predict VFDs.

CONCLUSIONS

Assessing VFDs is advisable, especially among patients with poor-grade aSAH (H&H grade IV or V) and ICH.

Long-term trends in glaucoma-related blindness in Olmsted County, Minnesota

OBJECTIVE

To determine the longitudinal trends in the probability of blindness due to open-angle glaucoma (OAG) in Olmsted County, Minnesota, from 1965 to 2009.

DESIGN

Retrospective, population-based cohort study.

PARTICIPANTS

All residents of Olmsted County, Minnesota (aged ≥ 40 years) who were diagnosed with OAG between January 1, 1965, and December 31, 2000.

METHODS

All available medical records of every incident case of OAG were reviewed until December 31, 2009, to identify progression to blindness, defined as visual acuity ≤ 20/200 or visual field constriction to ≤ 20°. Kaplan-Meier analysis was used to estimate the cumulative probability of glaucoma-related blindness. Population incidence of blindness within 10 years of diagnosis was calculated using US Census data. Rates for subjects diagnosed in the period 1965-1980 were compared with rates for subjects diagnosed in the period 1981-2000 using log-rank tests and Poisson regression models.

MAIN OUTCOME MEASURES

Cumulative probability of OAG-related blindness and population incidence of blindness within 10 years of diagnosis.

RESULTS

Probability of glaucoma-related blindness in at least 1 eye at 20 years decreased from 25.8% (95% confidence interval [CI], 18.5-32.5) for subjects diagnosed in 1965-1980 to 13.5% (95% CI, 8.8-17.9) for subjects diagnosed in 1981-2000 (P = 0.01). The population incidence of blindness within 10 years of the diagnosis decreased from 8.7 per 100,000 (95% CI, 5.9-11.5) for subjects diagnosed in 1965-1980 to 5.5 per 100,000 (95% CI, 3.9-7.2) for subjects diagnosed in 1981-2000 (P = 0.02). Higher age at diagnosis was associated with increased risk of progression to blindness (P < 0.001).

CONCLUSIONS

The 20-year probability and the population incidence of blindness due to OAG in at least 1 eye have decreased over a 45-year period from 1965 to 2009. However, a significant proportion of patients still progress to blindness despite recent diagnostic and therapeutic advancements.

The Glenn A. Fry award lecture 2010: Ophthalmic markers of diabetic neuropathy

Diabetic peripheral neuropathy (DPN) is a debilitating condition that affects about 50% of diabetic patients. The symptoms of DPN include numbness, tingling, or pain in the arms and legs. Patients with numbness may be unaware of foot trauma, which could develop into a foot ulcer. If left untreated, this may ultimately require amputation. Currently, the only method of directly examining peripheral nerves is to conduct skin punch or sural/peroneal nerve biopsies, which are uncomfortable and invasive. Indirect methods include quantitative sensory testing (assessing responses to heat, cold, and vibration) and nerve electrophysiology. Here, I describe research undertaken in my laboratory, investigating the possibility of using a range of ophthalmic markers to assess DPN. Corneal nerve structure and function can be assessed using corneal confocal microscopy and non-contact corneal esthesiometry, respectively. Retinal nerve structure and visual function can be evaluated using optical coherence tomography and perimetry, respectively. These techniques have been used to demonstrate that DPN is associated with morphological degradation of corneal nerves, reduced corneal sensitivity, retinal nerve fiber layer thinning, and peripheral visual field loss. With further validation, these ophthalmic markers could become established as rapid, painless, non-invasive, sensitive, reiterative, cost-effective, and clinically accessible means of screening for early detection, diagnosis, staging severity, and monitoring progression of DPN, as well as assessing the effectiveness of possible therapeutic interventions. Looking to the future, this research may pave the way for an expanded role for the ophthalmic professions in diabetes management.

The volume of tumor mass and visual field defect in patients with pituitary macroadenoma

PURPOSE

We used the Swedish interactive threshold algorithms (SITA) standard strategy of Humphrey perimetry, to analyze the pattern of visual field (VF) defects and evaluate the quantitative correlation between the tumor volume and severity of VF defects in patients with pituitary macroadenoma.

METHODS

We reviewed 50 patients with pituitary macroadenoma who received VF test and 11 patients were excluded. VF analysis was performed with Humphrey perimeter using the SITA standard strategy. The tumor volume was assessed radiologically via brain magnetic resonance images and was calculated using Cavalieri's principle. We used the mean deviation (MD) and pattern standard deviation (PSD) of the Humphrey parameter to measure VF defect severity, and then analyzed the correlation of tumor volume with VF defects.

RESULTS

Twenty nine patients (74%) showed abnormal VF and bitemporal field changes, which were the most common field defects on presentation. Seven patients (18%) had unilateral VF defects, 22 patients (56%) had bilateral VF defects. The tumor volume of the patients with VF defects was significantly larger than that of patients with normal VF (p = 0.006). The tumor volume exhibited significant negative correlation with MD (r = -0.693; p < 0.001) and significant positive correlation with PSD (r = 0.589; p < 0.001).

CONCLUSIONS

In patients with pituitary macroadenoma, there was a variety of VF defects and a high correlation between the tumor volume and the severity of VF defects. SITA standard strategy can be a fast and quantitative method for evaluating central VF defects.

Exploring retinal and functional markers of diabetic neuropathy

Diabetic peripheral neuropathy (DPN) is one of the most debilitating complications of diabetes. DPN is a major cause of foot ulceration and lower limb amputation. Early diagnosis and management are key factors in reducing morbidity and mortality. Current techniques for clinical assessment of DPN are relatively insensitive for detecting early disease or involve invasive procedures such as skin biopsies. There is a need for less painful, non-invasive, safe evaluation methods. Eye-care professionals already play an important role in the management of diabetic retinopathy but recent studies have indicated that the eye may also be an important site for the diagnosis and monitoring of neuropathy. Corneal nerve morphology is a promising marker of diabetic neuropathy occurring elsewhere in the body. Emerging evidence tentatively suggests that retinal anatomical markers and a range of functional visual indicators could similarly provide useful information regarding neural damage in diabetes, although this line of research is less well established. This review outlines the growing body of evidence supporting a potential diagnostic role for retinal structure and visual functional markers in the diagnosis and monitoring of peripheral neuropathy in diabetes.

Prevalence of Glaucoma in the Wroclaw Population. The Wroclaw Epidemiological Study

PURPOSE

Primarily to determine the prevalence of various types of glaucoma and ocular hypertension in Wroclaw inhabitants aged 40-79 years. The second aim of the study was to determine the number of undiagnosed glaucoma cases in this population.

METHODS

A representative group of the Wroclaw population (4853 people aged from 40 to 79 years) was recruited by a proportional simple random sampling selection with stratification. All participants underwent the first, screening-stage examination, which included a medical history interview, intraocular pressure (IOP) measurement, anterior chamber depth assessment by the Van Herrick technique, and optic nerve head (ONH) assessment by means of indirect ophthalmoscopy (Volk's lens), confocal scanning laser ophthalmoscopy with a Heidelberg Retinal Tomograph (HRT) and scanning laser polarimetry by the GDx Nerve Fiber Analyzer (GDx). The second stage, in glaucoma-suspect patients only, included best corrected visual acuity, static perimetry, 24-hour monitoring of IOP, gonioscopy, and full eye examination with mydriasis. Glaucoma was diagnosed by the presence of any two of the following: characteristic morphological changes in the optic disc, glaucomatous visual field abnormalities, and intraocular pressure greater than 21 mmHg.

RESULTS

The overall prevalence of glaucoma was 1.6% (79 subjects). The prevalence increased with age from 0.4% in subjects belonging to the age group 40-49 years to 4.6% in people aged between 70 and 79 years. The prevalence of definite primary open-angle glaucoma was 1.0% (49 subjects). Normal-pressure glaucoma was diagnosed in 13 subjects (0.3%). Ocular hypertension was diagnosed in 92 subjects (1.9%).

CONCLUSION

The prevalence of the different types of glaucoma was similar to that found in other white populations. Among the subjects examined, 79 had various forms of glaucoma and 71% of them had not previously been diagnosed. Undiagnosed glaucoma is a serious public health problem in Poland.

Using frequency-doubling perimetry to detect optic neuropathy in patients with Graves' orbitopathy

PURPOSE

to test the ability of frequency-doubling technology (FDT) perimetry to detect dysthyroid optic neuropathy (DON).

METHODS

Fifteen eyes of 15 patients with DON and 15 healthy control eyes were studied. Eligible eyes had a diagnosis of DON based on visual field abnormalities on standard automated perimetry and had visual acuity better than 20/30. FDT testing was performed using both the C-20-5 screening test and the C-20 full-threshold test. Normal and DON eyes were compared with regard to FDT mean sensitivity.

RESULTS

Sensitivity ranges were 40.0%-86.7% for the screening test, and 53.3%-100.0% (total deviation) and 20.0-93.3 (pattern deviation) for the C-20 threshold test. The corresponding specificity ranges were 86.7-100.0, 33.3-93.3, and 26.7-100.0, respectively. The best sensitivity/specificity ratios were for one abnormal point depressed <5% in the screening test (86.7%/86.7%), one point depressed <1% in the total deviation analysis (80.0%/86.7%), and one point depressed <2% in the pattern deviation analysis (80.0%/86.7%). DON eyes presented significantly lower than normal average sensitivity in the central, pericentral, and peripheral areas.

CONCLUSIONS

FDT perimetry is a useful screening tool for DON in eyes with normal or only slightly reduced visual acuity.

The use of semi-automated kinetic perimetry (SKP) to monitor advanced glaucomatous visual field loss

PURPOSE

(i) To compare visual field (VF) results obtained with semi-automated kinetic perimetry (SKP) and automated static perimetry (ASP) in patients with advanced glaucomatous VF loss, (ii) to evaluate test-retest reliability of SKP and ASP and (iii) to assess patients' preference for SKP and ASP.

METHODS

Twenty eyes of 20 patients (11 male, 9 female, aged 38 to 83 years) with advanced glaucomatous VF loss (stage III or IV according to the Aulhorn classification). Each of the 20 patients were examined in 4 sessions every 3 months with SKP (Goldmann stimulus III4e, I4e and at least one additional dimmer stimulus, within the 90 degrees visual field) and ASP within the 30 degrees VF, employing a threshold-related, supra-threshold test strategy with high spatial resolution for the same instrument (Octopus 101 perimeter, Haag-Streit Inc., Koeniz, Switzerland).

RESULTS

Visual field areas (VFA) were compared by analyses of covariance (ANCOVA) with co-variable time, patient effect and their interaction. Test-retest reliability was assessed by ratios (R) of intersection and union of VFA: The mean VFA within the 30 degrees of VF at baseline was 2,344 square degrees (deg(2)) with SKP (Goldmann stimulus III4e) and 1,844 deg(2) with ASP. The patients showed stable visual fields for both SKP and ASP. Comparison of SKP with ASP of the same sessions revealed a median ratio of intersection and union of VFA of 0.78 with the III4e stimulus and of 0.79 with the I4e stimulus. When follow-up SKPs were compared with baseline SKPs the median of the ratios was between 0.80 and 0.93 for the different isopters. The corresponding ratio of ASP's follow-up and baseline VFs was 0.81 (with the size III static stimulus). Nineteen of 20 patients preferred kinetic perimetry to static perimetry.

CONCLUSIONS

The comparability between SKP and ASP is satisfactory and within the range of the test-retest reliability of ASP. SKP shows slightly better test-retest reliability than ASP. The majority of patients with advanced glaucomatous visual field loss prefer SKP instead of ASP. SKP is a valuable alternative to ASP in monitoring advanced glaucomatous visual field loss.

Prevalence of open-angle glaucoma in Greece: the Thessaloniki Eye Study

PURPOSE

To estimate the prevalence of open-angle glaucoma (OAG) in a population-based sample of subjects 60 years of age or older in Thessaloniki, Greece.

DESIGN

Cross-sectional population-based study.

METHODS

Subjects randomly identified from municipality registers in Thessaloniki underwent a complete ophthalmologic examination. Glaucoma was defined in two ways. Definition 1 was based on the presence of both glaucomatous optic disk and confirmed glaucomatous visual field defect. Subjects also were classified as having glaucoma when the clinical judgment was strongly in favor of the presence of glaucoma even though the strict criteria were not fulfilled (definition 2).

RESULTS

Of the 3,617 eligible subjects, 2,554 (71%) participated. The prevalence of OAG was 3.8% and 5.5% by definitions 1 and 2, respectively. The prevalence of primary OAG was 2.7% and 3.8% by definitions 1 and 2, respectively, and the prevalence of pseudoexfoliation glaucoma (PEXG) was 1.1% and 1.7% by definitions 1 and 2, respectively. Pseudoexfoliation was present in 11.9% of participants, whereas 15.2% among those with pseudoexfoliation had PEXG.

CONCLUSIONS

The prevalence of OAG in the Thessaloniki Eye Study (TES) is similar or slightly higher compared with other population-based studies in White persons. The overall slightly higher prevalence of OAG in the TES compared with other studies may be attributed to the high prevalence of PEXG in the TES.

Longitudinal glaucoma screening for siblings of patients with primary open angle glaucoma: the Nottingham Family Glaucoma Screening Study

AIMS

To assess the prevalence and cumulative incidence of open angle glaucoma (OAG) in a cohort group of siblings of OAG probands.

METHODS

Between 1994 and 2003, a group of siblings of OAG probands underwent both initial and follow up standardised ophthalmic examinations. Siblings were classified as "definite glaucoma" (primary OAG (POAG) and normal tension glaucoma (NTG)), "glaucoma suspects" (NTG suspects or ocular hypertension (OHT)), and normal. The prevalence and cumulative incidence of OAG over the follow up interval were calculated.

RESULTS

At the initial study, 271 siblings (mean age 63.6 years; female to male ratio 1.2) from 156 probands were examined. 32 (11.8%) were classified as definite glaucoma and 15 (5.5%) as suspects. In the follow up study, 157 of the 224 "normal" siblings from the initial study were examined (mean interval from initial study 7.0 (SD 1.0) years). 11 (7%) were classified as definite glaucoma and 30 (19.1%) as suspects. There were significant trends of increasing prevalence and incidence of OAG with age and a lifetime risk estimated at approximately 20% by age 70.

CONCLUSION

Siblings of glaucoma patients have an increased risk of developing glaucoma and the risk increases with age. An effective and repeated screening programme should be considered for this high risk group.

Risk and risk factors for blindness from glaucoma

PURPOSE OF REVIEW

Estimates of blindness from glaucoma and risk factors for blindness remain of interest for all ophthalmologists.

RECENT FINDINGS

Long-term retrospective studies of patients with open-angle glaucoma in developed countries have noted that progression to bilateral blindness among treated patients is relatively uncommon. Risk factors for development of blindness include advanced visual field loss at presentation and noncompliance with the treatment regimen. Age is a risk factor in some studies. Many of those with blindness are blind at presentation. Untreated rates of blindness are higher. Population-based studies of glaucoma in developing countries have highlighted the obstacles to prevention of blindness in such settings, with astonishingly high rates of blindness noted.

SUMMARY

The risk of blindness from glaucoma is very high among patients in developing countries, the vast majority of whom do not know they are afflicted. When considering all glaucoma worldwide, the greatest risk factor for blindness is almost certainly being an average citizen of a developing country. Among those with open-angle glaucoma in developed countries, more advanced visual field loss at presentation and noncompliance are risk factors for development of blindness, as well as advanced age. Effective public education about glaucoma and targeted screening of those most likely to have glaucoma are necessary if the number of blind from glaucoma is to be reduced worldwide. Better treatment options for those in developing countries must also be developed.

Patterns of visual field defects in chronic angle-closure glaucoma with different disease severity

PURPOSE

To evaluate the patterns of visual field defects in patients with chronic angle-closure glaucoma (CACG) with varying extent of optic nerve damage.

DESIGN

Prospective, consecutive, observational case series.

PARTICIPANTS

One hundred forty-six Asian patients with well-controlled CACG.

METHODS

Visual field tests were performed using program 24-2 of the Humphrey Field Analyzer (Humphrey Instruments, San Leandro, CA) with the Swedish interactive thresholding algorithm standard. One hundred ten eligible visual fields were scored with the system adopted by the Advanced Glaucoma Intervention Study and were categorized into 4 groups accordingly: mild, moderate, severe, and end-stage. Each hemifield was divided into the nasal, paracentral, and arcuate areas, and field loss that involved respective areas was defined as nasal step, paracentral scotoma, and arcuate scotoma.

MAIN OUTCOME MEASURES

The distribution of field defect patterns in each group was evaluated. The mean deviation (MD) was compared among the 3 areas within one hemifield and between each pair of corresponding areas across the median raphe.

RESULTS

The nasal area was the most commonly damaged area in the mild group, being noted in 52% of eyes in the superior hemifield and 58% of eyes in the inferior hemifield. In the moderate group, field loss involving both the nasal and arcuate areas dominated the superior hemifield, whereas field loss involving all three areas dominated the inferior hemifield. The MD of the nasal area was the worst among the three areas in each hemifield of the mild and moderate groups, as well as in the inferior hemifield of the severe group (all P < 0.001). There were no significant differences in the MD of each area between the superior hemifield and their inferior counterparts. However, the superior hemifield as a whole showed a better MD than the inferior hemifield (P=0.034) in the mild group.

CONCLUSIONS

Visual field loss that involved the nasal area was the most common pattern in the early stage of CACG. The MD of the nasal area was worse than those of the arcuate and the paracentral areas within the same hemifield in the mild, moderate, and severe groups of CACG patients.

Patterns of glaucomatous visual field defects in an older population: the Blue Mountains Eye Study

This report aims to describe the frequency of different patterns of visual field loss in open-angle glaucoma (OAG). The Blue Mountains Eye Study examined 3654 persons (aged 49+) during 1992-1994. Humphrey supra-threshold visual fields were performed in 88.9%. Those classified as glaucoma suspects had 30-2 full-threshold fields (9.2%). Of OAG cases (n = 108) with field tests in both eyes (n = 97), unilateral defects were present in 49 (50.5%) and bilateral in 48 (49.5%). Advanced field loss was found in 16 (15.4%) subjects and in 22 (10.9%) eyes, with bilateral loss present in 6 (6.2%) cases. Of all eyes of OAG cases (n = 201), 49 (24.4%) had no defects, 52 (25.9%) upper, 61 (30.3%) lower, and 17 (8.5%) had combined upper and lower loss. Of the upper and lower cases (n = 113), the types of defects included nasal step (36), arcuate (26), nasal plus arcuate (26), and hemispherical defects (25). Of subjects with fields in at least one eye (n = 104), there was a similar proportion in the worse eye of upper defects (28.8%), lower (31.7%), and combined upper and lower (24.0%). Undiagnosed OAG was more frequent in unilateral (65.3%) than bilateral (34.7%) cases (P = 0.003). This study reports the pattern of typical glaucomatous field loss in an older Australian population.

Blindness in patients with treated open-angle glaucoma

PURPOSE

To investigate blindness in patients with treated open-angle glaucoma (OAG) and risk factors for blindness.

DESIGN

Retrospective observational case series.

PARTICIPANTS

One hundred eighty-six patients seen between April and November 2000 at the University of Washington Medical Center Eye Clinic, diagnosed in 1975 or later, and treated for at least 2 years for OAG.

METHODS

Chart review with evaluation of visual acuity and visual field. Kaplan-Meier survival analysis was used to estimate the risk of blindness in one and both eyes. Variables considered to be possible risk factors for blindness were evaluated using chi-square test, t test, and Cox proportional hazards regression analysis.

MAIN OUTCOME MEASURES

Blindness, defined as visual acuity of 20/200 or worse, and/or continuous constriction of the visual field to 20 degrees or less in all four quadrants with a size III4e Goldmann stimulus or the equivalent on automated perimetry, allowing a higher threshold level on one point in one quadrant on automated perimetry.

RESULTS

The mean duration of disease was 10.2 +/- 4.9 years. Twelve patients were blind in at least one eye from OAG at diagnosis. Nineteen other patients became blind in at least one eye from OAG, and three patients became bilaterally blind from OAG. The Kaplan-Meier estimate for blindness at 15 years in one eye was 14.6%, and in both eyes was 6.4%. Noncompliance with the treatment regimen (P = 0.016) and worse initial visual field loss (P < 0.0001) were significantly associated with development of blindness. Nonwhite race was associated with blindness (P = 0.014) when all blindness, including that found at diagnosis, was considered in the analysis.

CONCLUSIONS

Bilateral blindness from chronic OAG was uncommon in this population of treated patients diagnosed in 1975 or later. Of patients with a blind eye, 39% were blind at diagnosis, and worse visual field loss at diagnosis and noncompliance were associated with development of blindness.

Visual fields and tiagabine: a quandary

This case report describes the development of asymptomatic visual field defects (VFDs) in a psychiatric patient with bipolar disorder receiving adjunctive tiagabine treatment. These defects were apparently reversible upon the discontinuation of tiagabine. Controlled clinical trials are indicated to determine if this finding is indicative of a class effect for all GABAergic antiepileptic drugs (AEDs), as already noted with vigabatrin, or if this case represents an incidental finding with tiagabine (41 references).

The visual field following acute primary angle closure

PURPOSE

To determine the frequency and type of visual field loss six months after an episode of acute primary angle closure (APAC), and to identify risk factors for the development of such field loss.

METHODS

This was a cross sectional observational study. All patients who suffered from an episode of APAC at two Singapore hospitals over a one-year period underwent static automated threshold perimetry six months after presentation.

RESULTS

38% of (29) patients with APAC have significant visual field defects six months after the acute episode. The majority of those with abnormal fields had hemifield defects, consistent with nerve fiber bundle pattern loss. Those with pre-existing chronic glaucoma or who develop a rise in intraocular pressure during follow-up are at risk of visual field loss. The risk of visual field loss is also significant if the duration of symptoms exceeds 7 days.

CONCLUSIONS

The frequency of visual field loss at 6 months after APAC was low at only 38%. As the majority of eyes have no evidence of detectable functional damage developing as a consequence of the acute episode, APAC may not be blinding if treated promptly and adequately.

Visual field progression in patients with initially unilateral visual field loss from chronic open-angle glaucoma

PURPOSE

To investigate visual field progression in patients with initially unilateral glaucomatous visual field loss, and to determine risk factors for progression.

DESIGN

Retrospective observational case series.

PARTICIPANTS

Forty-eight consecutive patients with primary open-angle glaucoma, pseudoexfoliative glaucoma, or pigmentary glaucoma, seen over an 18-month period, who initially had unilateral visual field loss as defined by use of modified Anderson criteria. Patients were followed with standard Humphrey perimetry for a minimum of 2 years.

METHODS

Progression was defined by use of modified Anderson criteria, and Advanced Glaucoma Intervention Study (AGIS) and Collaborative Initial Glaucoma Treatment Study scores.

MAIN OUTCOME MEASURE

Visual field progression.

RESULTS

Three patients (6.2%) had fellow eye progression over a mean follow-up of 76 months and duration of disease of 8.7 years. Fellow eye progression correlated with progression of the first-affected eye (P = 0.044). Ten patients (21%) had progression of the first-affected eye; these eyes had a larger initial cup/disc ratio compared with stable eyes (P = 0.041). Increasing initial AGIS score was associated with progression (P: = 0.003). Kaplan-Meier survival analysis estimated the risk of progression at 5 years to be 25% in first-affected eyes and 7.2% in fellow eyes.

CONCLUSIONS

In this population, the risk of fellow eye progression in patients with initially unilateral visual field loss from open-angle glaucoma is low. Progression is higher in eyes with visual field loss at initial testing, and the risk of progression increases as the level of initial visual field loss increases.

Goldmann perimetry in acromegaly: a survey of 307 cases from 1951 through 1996

OBJECTIVE

Because visual pathway lesions are a common complication of pituitary tumors, visual field examinations in patients with acromegaly were studied. Proportion and outcome of visual field defects in patients with acromegaly were evaluated.

DESIGN

Large, retrospective case series.

PARTICIPANTS

We reviewed 307 cases of acromegaly seen from 1951 through 1996 at a single referral center.

METHODS

Kinetic visual field testing had been performed with the Goldmann perimeter, and the frequency of visual field defects and their correlation with other clinical manifestations and characteristics of the adenoma were examined.

MAIN OUTCOME MEASURES

Repeat visual field examinations.

RESULTS

Of the 307 patients included in the analysis, a visual field defect that could be attributed to the pituitary adenoma was observed in 62 (20.2%) during follow-up. Visual field defects were bilateral in 38 (61.3%) of these cases. Patients with visual field abnormalities were significantly younger (P = 0.04), had larger tumors (P < 0.001), had more suprasellar extensions (P < 0.001), and had higher levels of growth hormone in their serum (P = 0.04) than patients free of visual field defects. At the end of the follow-up period, visual field examination remained abnormal in 32 (10.4%). Return to a normal visual field examination after treatment was more frequently observed in patients who were less than 40 years of age at the time of diagnosis (P = 0.004). Secondary empty sella syndrome was the main cause of visual field defects after treatment. Abnormal visual field, either at the time of diagnosis or during follow-up, decreased from 27% of patients between 1951 and 1975 to 15.4% of patients between 1976 and 1996, when modern neuroimaging techniques became available.

CONCLUSIONS

Endocrinologic and neuroimaging follow-up of patients with acromegaly should be accompanied by ophthalmic assessment. Factors predictive of visual field defects have been identified.

A comparison of tangent screen, goldmann, and humphrey perimetry in the detection and localization of occipital lesions

OBJECTIVE

To compare manual kinetic perimetry with tangent screen and Goldmann techniques and automated static perimetry with the Humphrey Field Analyzer in the detection and localization of occipital lobe lesions.

DESIGN

Prospective consecutive comparative case series.

PARTICIPANTS

Twelve patients with well-defined occipital lobe infarcts on magnetic resonance (MR) imaging were studied.

MAIN OUTCOME MEASURES

The patients were tested by tangent screen, Goldmann, and Humphrey perimetry (central 30-2 threshold program). The three visual fields were compared and correlated with MR images.

RESULTS

All three perimetric techniques detected the presence of postchiasmal lesions. However, localization of lesions differed with perimetric technique. Visual fields obtained from tangent screen and Goldmann perimetry were similar and corresponded well with the location of lesions on MR images in all 12 patients. Humphrey perimetry inaccurately localized the lesion to the proximal part of the postchiasmal pathway by revealing incongruous fields in two patients, failed to detect sparing of the posterior occipital cortex or occipital pole in four patients, and estimated a larger extent of damage in one patient when compared with MR images and manual perimetry.

CONCLUSIONS

All three perimetric techniques are satisfactory screening tests to detect occipital lesions. However, tangent screen and Goldmann perimetry provide information about the location and extent of lesions that is more consistent with prevailing knowledge of the effects of the lesion in the postgeniculate visual pathway.

Perimetry techniques in neuro-ophthalmology

Advances in technology have produced several new techniques for evaluating the visual field. The standard Humphrey perimeter now has programs for SWAP (Short-wavelength automated perimetry) and SITA (Swedish interactive thresholding algorithm). SITA seems particularly promising as an automated test that decreases testing time without sacrificing sensitivity or increasing variability. In addition, separate tests have been developed that may selectively evaluate particular pathways of the afferent visual system. This paper summarizes major advances in perimetry published in 1998 and 1999.

A third locus (GLC1D) for adult-onset primary open-angle glaucoma maps to the 8q23 region

PURPOSE

Two genes for adult-onset primary open-angle glaucoma have been mapped to chromosomes 2cen-q13 and 3q21-q24. We studied a family with adult-onset primary open-angle glaucoma in which the disease did not map to these two chromosomal regions.

METHODS

We ascertained a four-generation family with adult-onset primary open-angle glaucoma in which the disease status of individuals was objectively assigned using defined criteria. Complete ophthalmologic examinations, visual field testing, optic nerve head photographs, and venous blood samples were obtained. Family members were genotyped using polymerase chain reaction amplification of microsatellite polymorphic markers. Linkage analysis was performed and lod scores were calculated. Haplotype transmission data were analyzed.

RESULTS

A total of 20 subjects in three successive generations agreed to participate in the study. This included samples from eight affected subjects, one glaucoma suspect, one normal individual, and two spouses in generations II and III, and an additional eight individuals in generation IV. The phenotype in this family appears to be variable, with onset of visual field loss in middle age, followed by modest elevation of intraocular pressure and progression of the disease in older individuals. Linkage was established with a group of DNA markers located in the 8q23 region. A lod score value of 3.61 was obtained using marker D8S1471. Three other markers from the same region gave lod score values of over 3.0. Haplotype transmission data identified two recombination events that placed the gene in a 6.3-cM region flanked by D8S1830 and D8S592. The disease-bearing haplotype was inherited by eight affected subjects and three glaucoma suspects.

CONCLUSION

We present evidence for a third adult-onset primary open-angle glaucoma locus (GLC1D) on chromosome 8q23. The genetic heterogeneity of adult-onset glaucoma is evident from the multiplicity of chromosomal loci associated with this disease.

Apparent glaucomatous visual field defects caused by dermatochalasis

We have studied the effects of dermatochalasis on Humphrey automated perimetry of the central 24 degrees visual field. Fifteen visual fields of 9 ocular hypertensive patients (18 eyes) were found to be incongruous with their apparently healthy optic discs. Examination revealed dermatochalasis, which was felt to be responsible for the field defects. This was confirmed by reversal of the defects on repeating the field test (programme 24-2) with the redundant upper lid skin taped up, or in 2 cases following blepharoplasty. The defects always involved the superior visual field. The deepest and largest defects were sited in the supero-temporal quadrant in 13 of the 15 affected fields and the supero-nasal quadrant in 2 fields. The most common pattern was a temporally skewed defect which reflected the tendency of the loose upper lid skin to be greater in extent temporally than nasally. In 7 fields the supero-temporal defect extended to fuse with the blind spot, mimicking a superior arcuate scotoma. Temporal extension of the field defects below the horizontal meridian occurred in 5 fields. In cases where visual field testing was repeated without taping up the lid inter-test fluctuation in scotoma size and depth was observed, although the position of scotomas when present within the visual field remained constant. We conclude that dermatochalasis has the potential to confound diagnostic automated visual field testing for glaucoma.

Lack of association between localized cataract and visual field loss: the Blue Mountains Eye Study

PURPOSE

To examine whether localized cataract is related to localized field defects on suprathreshold visual field testing.

METHODS

Suprathreshold screening visual fields (Humphrey 76-point test) and lens photographs, graded using the Wisconsin System, were performed on participants attending the Blue Mountains Eye Study, which examined 3654 subjects residing in an area west of Sydney, NSW, Australia. The results for 2276 subjects were analysed in the present study.

RESULTS

There were no significant relationships between total points missing in the visual field and the degree of cortical, posterior subcapsular (PSC) or nuclear cataract after adjusting for confounders (test for trend P = 0.9, 0.7 and 0.9, respectively). Adjusted prevalence ratios and 95% confidence limits for the association between 10 or more points missing and the presence of cataract were 0.94 (0.77-1.25) for cortical, 1.26 (0.82-1.93) for PSC and 1.06 (0.86-1.30) for nuclear cataract. Similarly, there was no relationship between the presence of cortical or PSC cataract and sectoral visual field loss in any quadrant or hemifield.

CONCLUSIONS

Neither cortical, nuclear nor PSC cataracts increase the total points missing on the 76-point suprathreshold field test. Similarly, neither cortical nor PSC cataracts cause sectoral visual field loss on this screening field test. In the presence of cataract, sectoral visual field loss on non-thresholding visual field screeners must be attributed to other causes, such as glaucoma. The present study provides a clinical alert that localized field loss is unlikely to be related to cataract.

Prevalence of open-angle glaucoma in Australia. The Blue Mountains Eye Study

PURPOSE

The purpose of this study was to determine the prevalence of open-angle glaucoma and ocular hypertension in an Australian community whose residents are 49 years of age or older.

SUBJECTS

There were 3654 persons, representing 82.4% of permanent residents from an area west of Sydney, Australia, who were examined. The population was identified by a door-to-door census of all dwellings and by closely matched findings from the national census.

METHODS

All participants received a detailed eye examination, including applanation tonometry, suprathreshold automated perimetry (Humphrey 76-point test), and Zeiss stereoscopic optic disc photography. Glaucoma suspects were asked to return for full threshold fields (Humphrey 30-2 test), gonioscopy, and repeat tonometry.

RESULTS

A 5-point hemifield difference on the 76-point test was found in 616 persons (19% of people tested). Humphrey 30-2 tests were performed on 336 glaucoma suspects (9.2% of population), of whom 125 had typical glaucomatous field defects. Two hundred three persons had enlarged or asymmetric cup-disc ratios (> or = 0.7 in 1 or both eyes or a cup-disc ratio difference of > or = 0.3). Open-angle glaucoma was diagnosed when glaucomatous defects on the 30-2 test matched the optic disc changes, without regard to the intraocular pressure level. This congruence was found in 87 participants (2.4%), whereas an additional 21 persons (0.6%) had clinical signs of open-angle glaucoma but incomplete examination findings. Open-angle glaucoma was thus found in 108 persons, a prevalence of 3.0% (95% confidence interval [CI], 2.5-3.6), of whom 49% were diagnosed previously. An exponential rise in prevalence was observed with increasing age. Ocular hypertension, defined as an intraocular pressure in either eye greater than 21 mmHg, without matching disc and field changes, was present in 3.7% of this population (95% CI, 3.1-4.3), but there was no significant age-related increase in prevalence. The prevalence of glaucoma was higher in women after adjusting for age (odds ratio, 1.5; CI, 1.0-2.2). There was no sex difference in the age-adjusted prevalence of ocular hypertension.

CONCLUSIONS

These data provide detailed age and sex-specific prevalence rates for open-angle glaucoma and ocular hypertension in an older Australian population.

Optic disc hemorrhages and progression of glaucoma

PURPOSE

To assess progressive changes of the optic nerve head and visual fields in patients with glaucoma and ocular hypertension after optic disc hemorrhage.

METHODS

The authors reviewed the charts of 91 patients with 121 disc hemorrhages who had a mean follow-up of 41.9 +/- 3.6 months. The frequency of visual field and optic nerve head changes in these patients was studied.

RESULTS

The mean intraocular pressure at the examination when the disc hemorrhage was noted was 18.9 +/- 0.5 mmHg. Overall, 64 (63%) of 101 eyes showed progressive changes of visual fields after disc hemorrhage, compared with 24 (24%) of 101 control eyes (P < 0.0005). Similarly, 56 (79%) of 71 eyes showed progressive changes of optic nerve head contour by masked evaluation of stereophotographs, compared with 16 (22%) of 71 control eyes (P < 0.0005). Eyes with disc hemorrhage showed significantly greater progression of visual field defects in patients with open-angle glaucoma (P < 0.001), low-tension glaucoma (P < 0.05), and ocular hypertension (P = 0.0067) compared with control eyes matched by age, follow-up time, and diagnosis. Similarly, progressive changes of optic nerve head contour were observed more often in eyes after disc hemorrhage in patients with open-angle glaucoma (P < 0.0005), low-tension glaucoma (P < 0.025), and ocular hypertension (P < 0.005), compared with controls. The mean time interval to progression after disc hemorrhage was observed was 16.8 +/- 2.0 months for visual field changes and 23.8 +/- 2.9 months for optic nerve head changes. In eyes with disc hemorrhage, 27 (22%) of 121 had recurrent hemorrhages at a mean interval of 21.5 +/- 2.9 months after previous hemorrhage. The most common site of disc hemorrhage was the inferotemporal quadrant. Eyes with disc hemorrhage that occurred on the temporal side of the optic nerve head had a significantly lower intraocular pressure (P < 0.02) and greater progressive changes of the optic discs (P < 0.001) compared with eyes with hemorrhage on the nasal side.

CONCLUSION

The authors' results indicate that disc hemorrhages in eyes with glaucoma or ocular hypertension often are associated with progressive changes of the optic nerve head and visual fields.

Detection of incident field loss using the glaucoma hemifield test

PURPOSE

To examine different definitions of incident visual field loss among patients with elevated intraocular pressure and varying numbers of abnormal glaucoma hemifield test results over an average of 6 years of follow-up.

METHODS

A cohort of patients with annual C-30-2 Humphrey visual fields were followed for a minimum of 5 years. Three different definitions of field loss were compared: 1, 2, or 3 consecutive annual abnormal glaucoma hemifield test results.

RESULTS

Of 253 subjects, 506 eyes were followed for 5 to 9 years. If incident field loss was defined as one or more normal fields followed by one abnormal glaucoma hemifield test result, the incidence of field loss was 63.6 per 1000 person-years of follow-up. For two or three consecutive abnormal glaucoma hemifield test results, the rates were 27.6 and 19.2 per 1000 person-years of follow-up, respectively. Among patients with field loss in one eye at the start of the study, the incidence of field loss in the fellow eye using 1, 2, or 3 consecutive abnormal fields as the definition of incident field loss was 60.9, 55.5, and 25.5 per 1000 person-years of follow-up, respectively. Three years after incident field loss, 31.9% (1 abnormal test result), 76.5% (2 abnormal test results), and 88.5% (3 abnormal test results) of eyes with incident field loss had an abnormal hemifield test result. For eyes with one, two, and three consecutive abnormal glaucoma hemifield test results at the start of the study, 59.2%, 83.6%, and 89.1%, respectively, had an abnormal field 3 years later.

CONCLUSIONS

One abnormal glaucoma hemifield test result is not a consistent criterion for defining incident field loss. The use of two or three consecutive abnormal fields to define incident field loss makes it more likely that subsequent test results will be abnormal.