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A Heijl

Publications and source records attributed to A Heijl.

At least 19 recordsLinked to original sources
PubMed2005

Visual acuity and perimetry as measures of visual function in diabetic macular oedema.

AIMS/HYPOTHESIS: We examined to what extent visual acuity and perimetric sensitivity as measures of central and paracentral visual function would be useful for evaluating the presence and severity of diabetic macular oedema. MATERIALS AND METHODS: We evaluated 59 eyes of 59 diabetic patients by identifying the presence (n=20) or absence (n=39) of macular oedema on stereo fundus photographs. The area of oedema and its distance to the centre of the macula were measured. Ischaemic macular damage was quantified by measuring the foveal avascular zone and adjacent perifoveolar intercapillary areas on fluorescein angiograms. Visual function was assessed by visual acuity charts and by short-wavelength perimetry and standard white-on-white perimetry of the central 10 degrees field. RESULTS: Visual acuity did not differ between eyes with and without macular oedema. In eyes with oedema, visual acuity was correlated to the distance of the oedema from the centre of the macula (log of minimum angle of resolution {LogMar} score decreased by 0.15/mm; p=0.006) and to the thickness of the retina when the centre was affected (LogMar score decreased by 0.003/mum of thickness; p=0.0002). Multivariate analyses confirmed the results (R (2)=0.46 and 0.77, respectively). Short-wavelength perimetry sensitivity was more depressed in eyes with oedema (p=0.033) but was not significantly associated with the presence of oedema after correction for macular ischaemic damage. There was no correlation between these field defects and the severity of oedema. CONCLUSIONS/INTERPRETATION: Visual acuity was a useful measure of visual function in diabetic macular oedema involving the centre. Visual field defects were more common in eyes with macular oedema but reflected ischaemic damage of the macula rather than macular oedema itself.

Adult↗
PubMed2005

Visual fields correlate better than visual acuity to severity of diabetic retinopathy.

AIMS/HYPOTHESIS: We compared the outcomes of perimetric and visual acuity tests in patients with diabetic retinopathy. METHODS: We examined 59 diabetic patients with different degrees of retinopathy using stereo fundus photography in accordance with the Early Treatment of Diabetic Retinopathy Study (ETDRS) and fluorescein angiography. Conventional white-on-white perimetry (WWP) and short wavelength automated perimetry (SWAP) were performed and analysed with reference to normal values. Visual acuity was measured with ETDRS charts. RESULTS: Regression analysis revealed that visual acuity was significantly associated with increasing severity of retinopathy according to the ETDRS scale when visual acuity was estimated by counting logarithm of minimum angle of resolution (LogMar) scores, but not when visual acuity was measured by the conventional reading of the smallest line that could be seen. Visual acuity decreased by 0.02 LogMar per ETDRS step (p=0.03). The degree of visual field loss was significantly associated with increasing severity of retinopathy according to the ETDRS scale, perimetric sensitivity decreasing by 0.44 dB per ETDRS step (p=0.0001) using WWP, and by 0.40 dB per ETDRS step (p=0.04) with SWAP. The size of the area of the foveal avascular zone and adjacent perifoveal intercapillary areas (PIAs) also affected the central visual field as obtained both by WWP (-2.6 dB/mm2, p=0.03), and by SWAP (-7.9 dB/mm2, p=0.002), but did not affect visual acuity. The regression model fit for peripheral retinopathy according to the ETDRS scale was better using WWP than SWAP or visual acuity, while SWAP testing was superior to both WWP and visual acuity when measuring effects caused by enlarged foveal avascular zones and PIAs. CONCLUSIONS/INTERPRETATION: Perimetry can provide more useful information than visual acuity on functional loss in diabetic retinopathy, particularly when the perifoveal capillary network is damaged.

Adult↗
PubMed2001

Timolol increased retrobulbar flow velocities in untreated glaucoma eyes but not in ocular hypertension.

PURPOSE: To investigate retrobulbar blood flow velocities and the effects of topical timolol treatment in eyes with newly detected, previously untreated open angle glaucoma or ocular hypertension. METHODS: Fifteen eyes with open angle glaucoma (OAG) and 12 eyes with ocular hypertension (OH), in the same number of patients, all untreated and newly detected, were examined with colour Doppler imaging of retrobulbar vessels before and after 1 month of topical timolol treatment (0.5% Timoptic BID). RESULTS: Baseline central retinal artery end diastolic velocity was lower (48%, p=0.0002) and resistive index higher (7.6%, p=0.018) in the OAG group than in the OH group. In the glaucoma group mean end diastolic velocity increased by 41%, (p=0.006) while resistive index decreased by 5.8%, (p=0.02) on treatment, while no significant changes were seen in the OH group. Blood flow velocities in the ophthalmic artery did not change with treatment. Baseline IOP and IOP reduction did not differ between OAG and OH group. CONCLUSION: Peripheral resistance to blood flow was found to be increased in untreated glaucoma eyes as compared to a similar group of eyes with ocular hypertension. Timolol treatment diminished resistance significantly in the glaucoma group, but not in the ocular hypertension group. Thus the two groups responded differently to timolol treatment. The reaction to IOP lowering treatment could indicate defective autoregulation in the glaucoma group.

Adrenergic beta-Antagonists↗
PubMed2001

Refractive error and glaucoma.

PURPOSE: To study the association between refractive error, glaucoma damage and IOP in a large population. METHODS: We examined 32,918 citizens of the city of Malmö, Sweden, 57-79 years of age, searching for individuals with undetected glaucoma. Refraction was measured with autorefractors. Glaucoma damage was defined as reproducible visual field defects with the Humphrey Full Threshold 24-2 program. RESULTS: Glaucoma prevalence was clearly associated with refractive state, increasing gradually with increasing myopia. This was seen both in males and females and persisted over the full age range. Glaucoma was significantly more common in myopic than in hyperopic eyes with low IOP readings (p=0.024). The overrepresentation of glaucoma in myopic eyes declined with increasing IOP and no relationship was observed in eyes with IOP > or =31 mmHg. CONCLUSION: In this large population, the prevalence of glaucoma increased with increasing myopia. The association between myopia and glaucoma was strong at lower IOP levels, and weakened gradually with increasing IOP. Our findings indicate that myopia is an important risk factor for glaucoma and particularly for normal tension glaucoma.

Aged↗
PubMed2001

Lack of long-term drift in timolol's effectiveness in patients with ocular hypertension.

PURPOSE: To report the change over time in intraocular pressure in patients treated with topical timolol or placebo. METHODS: Ninety patients with untreated ocular hypertension, defined as elevated intraocular pressure and normal visual fields, were randomly assigned to treatment and prospectively observed at 3-month intervals for up to 10 years in a double-masked fashion. The study end point was one eye showing reproducible glaucomatous field defects; patients were also withdrawn if one eye showed intraocular pressure of 35 mm Hg or higher. For each treatment group and visit, the mean and median of all intraocular pressure measurements were calculated. Medians were also calculated for the timolol group, assuming a worst-case scenario in which all patients who reached the end point, or intraocular pressure of 35 mm Hg or more, were assumed to show higher intraocular pressure than those remaining in the study. Distributions of slopes for intraocular pressure over time were compared between treatment groups. RESULTS: Means and medians of follow-up intraocular pressure over time did not differ between timolol- and placebo-treated patients. This was also true when assuming a worst-case scenario. Slopes of intraocular pressure over time did not differ statistically between treatment groups. CONCLUSIONS: In agreement with other masked and controlled studies and in conflict with uncontrolled ones, the present study did not demonstrate long-term drift of intraocular pressure in patients with ocular hypertension treated with topical timolol.

Adrenergic beta-Antagonists↗
PubMed2000

Glaucoma follow-up when converting from long to short perimetric threshold tests.

OBJECTIVES: To study the influence of test length in automated perimetry follow-up of glaucomatous eyes and, particularly, to determine if it is possible to usefully interpret test results obtained using a testing algorithm shorter than that used for baseline testing. METHODS: Automated perimetry findings were retrospectively evaluated in 31 patients with glaucoma for whom multiple Humphrey 30-2 tests were available on the Full Threshold strategy and the SITA Standard strategy. RESULTS: Variability around the mean deviation regression lines was smaller with SITA than with the Full Threshold strategy. Mean deviation values with SITA averaged about 1 dB less severe. Although localized scotomas measured in decibels were deeper on the Full Threshold strategy, number of significantly depressed points on total deviation and pattern deviation probability plot analyses did not differ significantly between the 2 strategies. CONCLUSIONS: The SITA strategy showed test-retest consistency that was at least as good as that of the Full Threshold strategy. The 2 strategies produced similar results when analyzed relative to their respective normal significance limits. Generally, it is appropriate to establish a new baseline when converting from one perimetric algorithm to another. When necessary, however, results may be usefully compared if such comparisons are based on total and pattern deviation probability maps rather than on decibel values.

Aged↗
PubMed2000

Long-term effects of timolol therapy in ocular hypertension: a double-masked, randomised trial.

BACKGROUND: Increased intraocular pressure (IOP) has been shown to be one of the most important risk factors for developing glaucoma. Yet it has not been clearly demonstrated that IOP-lowering treatment can reduce the incidence of glaucoma damage in patients with ocular hypertension. The aim of the current paper was to report the results of a long-term study addressing this very problem. METHODS: We conducted a randomised, double-masked study comparing timolol and placebo treatment in 90 patients with ocular hypertension plus some additional risk factor. Patients were followed at 3-month intervals prospectively for 10 years or until glaucomatous field loss could be demonstrated with computerised perimetry. A post-study analysis was performed including all available data, thus extending maximum follow-up to 17 years. RESULTS: After 5 years of follow-up eight patients in the placebo group and five patients in the timolol group had developed glaucomatous field loss (NS); the corresponding figures after 10 years were 15 patients in the placebo group and seven patients in the timolol group. Survival analysis showed a tendency but no statistically significant difference between treatment groups (P = 0.07). Study attrition was large. Eighteen patients in each group had developed glaucomatous field loss when also post-study data were included. IOP reduction was greater in eyes passing the 10-year visit without field loss (5.7 mmHg), than in those that reached an end-point (2.3 mmHg; P = 0.0002). CONCLUSION: In this long-term study we found a tendency but failed to prove a beneficial effect of topical timolol treatment in patients with elevated IOP, normal visual fields and some additional risk factor. The intent-to-treat analysis showed no difference between treatment groups. The high attrition shows the difficulties associated with very long follow-up.

Adrenergic beta-Antagonists↗
PubMed2000

Author's reply

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Journal Article↗
PubMed2000

Comparability of three-dimensional optic disc imaging with different techniques. A study with confocal scanning laser tomography and raster tomography.

PURPOSE: We wanted to compare optic nerve head topography measurements and discrimination between normal and glaucomatous eyes with two entirely different three-dimensional optic disc imaging techniques, confocal scanning laser tomography (Heidelberg Retina Tomograph, Heidelberg Engineering) and raster tomography (Glaucoma-Scope, Ophthalmic Imaging Systems). METHODS: Both eyes of 225 normal subjects and 229 eyes of 166 patients with glaucoma at different stages were imaged with the Heidelberg Retina Tomograph and the Glaucoma-Scope. Optics discs were analysed in 15 degrees sectors around the circumference. Depth measurements were calibrated on objects with known dimensions. RESULTS: We observed no significant differences in absolute measurements of maximum cup depth and cup area between the two instruments. We observed small differences in absolute measurements of disc anti rim area between the two instruments. Discrimination between normal and glaucomatous eyes was close to identical for the two instruments. Both instruments had the same ability to distinguish glaucomatous regional alterations of optic nerve head topography from normal disc configuration. CONCLUSION: Both instruments while using entirely different principles for three-dimensional optic disc imaging gave very similar results. This correspondence of results implies that the same optic disc parameters can be analysed, and the results interpreted similarly for both methods, and probably with other three-dimensional imaging instruments. It may also indicate that results of studies with one of the instruments have general validity.

Adult↗
PubMed2000

False-negative responses in glaucoma perimetry: indicators of patient performance or test reliability?

PURPOSE: To study whether false-negative answers in computerized glaucoma perimetry indicate the patient's ability to perform perimetry or test result reliability. METHODS: A retrospective evaluation was performed of visual field test results obtained with a perimetry program (Humphrey 30-2 Sita Standard; Humphrey Instruments, San Leandro, CA) in 70 consecutive patients with unilateral glaucomatous field loss. Frequencies of false-negative answers were compared between the two eyes of each patient and related to amount of visual field damage in the glaucomatous eyes using linear regression analysis. RESULTS: Frequencies of false-negative answers were higher in eyes with field loss. The intrapatient intereye difference was 6.6% on average (P < 0.0001). In seven subjects with false-negative frequency of 5% or more in both eyes, the mean difference was 12.7% between eyes. The differences in false-negative answers depended significantly on the amount of field loss in the glaucomatous eyes (P = 0.0003). Larger differences were seen in patients with advanced field loss in the affected eye. CONCLUSIONS: The increased frequencies of false-negative answers in eyes with field loss were strongly associated with field status. The higher false-negative frequencies in eyes with glaucomatous field loss compared with unaffected eyes may be explained by the increased variability in threshold values typically found in such eyes. False-negative answers in patients with glaucoma therefore represent eye rather than patient status.

Adult↗
PubMed1999

[New concept of glaucoma. Primarily an optic neuropathy, not a disease of the anterior chamber angle].

Glaucoma is now considered to be primarily an optic neuropathy, not a disease of the anterior chamber angle. Although intraocular pressure remains a crucial variable, the relationship between increased intraocular pressure and glaucoma is now recognised as being less simple than formerly believed. The new approach to the disease is reflected in a review by the National Board of Health and Welfare of the most recent advances in our knowledge of open-angle glaucoma, advances made possible by improvements in diagnostics and epidemiology. The prognosis of glaucoma is considerably better than often appreciated, by the profession and by the general public.

Controlled Clinical Trials as Topic↗
PubMed1999

Early Manifest Glaucoma Trial: design and baseline data.

OBJECTIVES: The Early Manifest Glaucoma Trial (EMGT) will evaluate the effectiveness of reducing intraocular pressure (IOP) in early, previously untreated open-angle glaucoma. Its secondary aims are to explore factors related to glaucoma progression and to study the natural history of the disease. This article describes the EMGT design and presents baseline data. DESIGN: Randomized, clinical trial. PARTICIPANTS: Newly diagnosed patients 50 to 80 years of age with early glaucomatous visual field defects were mainly identified from a population-based screening of more than 44,000 residents of Malmö and Helsingborg, Sweden. Exclusion criteria were advanced visual field loss; mean IOP greater than 30 mmHg or any IOP greater than 35 mmHg; visual acuity less than 0.5; and inability to complete follow-up protocols. INTERVENTIONS: After informed consent, patients were randomized to treatment or no initial treatment with close follow-up. Treated patients had laser trabeculoplasty and started receiving topical betaxolol twice daily in eligible eyes. Follow-up visits include computerized perimetry and tonometry every 3 months and fundus photography every 6 months. Decisions to change or begin treatment are made jointly with the patient when EMGT progression occurs and also later if clinically needed. MAIN OUTCOME MEASURES: The EMGT progression is defined by sustained increases of visual field loss in three consecutive C30-2 Humphrey tests, as determined from computer-based analyses, or by optic disc changes, as determined from flicker chronoscopy and side-by-side comparisons of fundus photographs performed by masked, independent graders. RESULTS: A total of 255 patients were randomized between 1993 and 1997 and will be followed for at least 4 years. All had generally good health status; mean age was 68.1 years, and 66% were women. At baseline, mean IOP was 20.6 mmHg and 80% of eyes had IOP less than 25 mmHg. CONCLUSIONS: The Early Manifest Glaucoma Trial is the first large randomized, clinical trial to evaluate the role of immediate pressure reduction, as compared to no initial reduction, in patients with early glaucoma and normal or moderately elevated IOP. Its results will have implications for: (1) the clinical management of glaucoma; (2) understanding the role of IOP and the natural history of glaucoma; and (3) evaluating the rationale for glaucoma screening.

Adrenergic beta-Antagonists↗
PubMed1999

Optic nerve head sector analysis recognizes glaucoma most effectively around disc poles.

PURPOSE: To analyze the topography of normal and glaucomatous discs with the goal of developing improved strategies to discriminate between normal and glaucomatous eyes. SUBJECTS AND METHODS: Raster tomography was performed in both eyes of 225 healthy subjects and in 296 eyes of 214 glaucoma patients. Cup area, average cup radius, rim area and minimal rim width were measured in 24 sectors around the optic nerve head at nine different depths from the reference plane. Receiver Operating Curves (ROC) for numerous combinations of parameter, sector and depth were calculated and compared. RESULTS: Discrimination between glaucomatous and normal eyes varied widely between single sectors of the optic disc, and was best at the vertical poles of the disc, intermediate in nasal sectors and worst in temporal sectors. When single sectors or combinations of sectors at the superior pole were combined with their counterparts at the inferior pole of the optic nerve, the gain in sensitivity exceeded the loss in specificity, and discrimination improved. Separation declined dramatically if any of the 8 temporal sectors were involved in such analysis. Depth influenced discrimination only slightly. CONCLUSION: Single sectors located close to the vertical meridian yielded better discrimination than global measurements. When two or more sectors at the superior pole were combined with each other, as well as with their counterparts at the inferior pole, discrimination improved even further. Localized changes concurred frequently, but asymmetrically at both poles of the disc. The depth from reference plane used to define the cup was not critical for separation between normal and glaucomatous eyes.

Adult↗
PubMed1999

Inter-subject variability and normal limits of the SITA Standard, SITA Fast, and the Humphrey Full Threshold computerized perimetry strategies, SITA STATPAC.

PURPOSE: To establish and evaluate inter-subject variability and normal threshold limits for the new SITA strategies and to compare them with those obtained with the traditional Humphrey Full Threshold algorithm. METHODS: Data from 330 eyes of 330 normal subjects were collected at 10 centres in order to establish limits of normality for the new SITA strategies and thus, to make it possible to subject SITA fields to computer-assisted visual field analysis. Two visual field tests were obtained with each of the SITA Standard, SITA Fast, and the Full Threshold algorithms. RESULTS: Inter-subject variance was 31% smaller with SITA Standard and 41% smaller with SITA Fast than with Full Threshold (p<0.0001). Age-dependent decrease of differential light sensitivity was also significantly smaller with both SITA algorithms than with Full Threshold (p<0.0001), 23% and 25% respectively. Mean sensitivity was somewhat higher with both SITA Standard (29.5 dB) and SITA Fast (29.9 dB) as compared to Full Threshold (28.3 dB) (p<0.0001). Normal limits were tightened between 9 to 29% at different significance levels with SITA. CONCLUSION: SITA test results from eyes with normal visual fields will on average be more even from centre to mid-periphery as compared with Full Threshold fields. They will also appear slightly lighter in grey-scale representations. Because of smaller inter-subject variance, shallower depressions are needed in SITA fields for statistical and clinical significance.

Adult↗
PubMed1999

Comparing significance and magnitude of glaucomatous visual field defects using the SITA and Full Threshold strategies.

PURPOSE: To evaluate and compare visual field test results as presented by the Statpac interpretation tools in tests obtained with the new short SITA Standard and the even shorter SITA Fast strategies to the traditional Humphrey Full Threshold strategy. SUBJECTS AND METHODS: One eye of each of 44 glaucoma patients was examined four times with each of the Humphrey SITA Standard, SITA Fast, and Full Threshold strategies. Another 21 eyes of 21 normal subjects had one eye examined once with each of the three strategies. RESULTS: Average light sensitivity was highest with the shortest SITA Fast strategy and lowest with the longest Full Threshold strategy. Magnitude of field loss as defined by the Statpac Mean Deviation (MD) did not differ between the three strategies. In the glaucoma patients, both SITA strategies showed larger number of significantly depressed points in Statpac probability maps than the Full Threshold strategy. In the normal subjects SITA Standard showed more significantly depressed points, close to the statistically expected number, at the lowest probability level (p<5%) than both Full Threshold and SITA Fast. At higher probability levels (p<1%) SITA Standard and Full Threshold showed similar numbers of significantly depressed points. CONCLUSION: Both SITA Standard and SITA Fast identified at least as much significant glaucomatous field loss as the Full Threshold using the Statpac interpretation tools.

Adult↗