Focal electroretinograms and fundus appearance in nonexudative age-related macular degeneration

· Background: The aim of this study was to evaluate the focal electroretinogram (FERG), an objective indicator of outer retinal function, in nonexudative age-related macular degeneration (NE-AMD), and to compare FERG results with morphological lesions assessed by stereoscopic fundus photographs and fluorescein angiograms. · Methods: Twenty-five patients (25 eyes) with bilateral NE-AMD (visual acuity of the study eyes ≥0.4) as well as 10 age- and sex-matched control subjects (10 eyes) were evaluated. FERGs were recorded from the macular region (9°) in response to sinusoidal stimuli flickered at 32 Hz. Amplitude and phase angle of the Fourier-analyzed FERG fundamental component were measured. Fundus lesions were graded from color slides according to the Wisconsin age-related maculopathy grading system [15]. Fluorescein angiograms were evaluated by an image analysis technique to compute the area with pathological hyperfluorescence (associated with drusen and/or retinal pigment epithelial atrophy) within the macular (approximately 9°×9°) region. · Results: Compared to control eyes, NE-AMD eyes had a reduction in the mean FERG amplitude (57% loss, P<0.001) with no phase changes. Amplitudes of individual affected eyes were negatively correlated with either the Wisconsin grading score (r=–0.63, P<0.001) or the percentage area of pathological hyperfluorescence (r=–0.70, P<0.01). Eyes with minimal NE-AMD lesions (Wisconsin score ≤6) and normal acuity had a lower mean amplitude (47% loss, P<0.05) than that of control eyes. · Conclusions: The results indicate that, in NE-AMD, the FERG is altered in parallel with the extent and severity of fundus lesions. However, a functional impairment of outer macular layers, which is detected by FERG losses, could precede morphological changes typical of more advanced disease. Received: 6 March 1998 Revised version received: 5 June 1998 Accepted: 17 June 1998     

Subretinal fibrosis and choroidal neovascularization in Vogt-Koyanagi-Harada syndrome

· Background: To describe clinical findings of subretinal fibrosis and choroidal neovascularization in patients with Vogt-Koyanagi- Harada (VKH) syndrome. · Methods: We retrospectively reviewed 75 medical records of patients with VKH seen at the National Eye Institute, Bethesda, Maryland between 1978 and 1996. Recorded data included age, gender, race, duration of disease, extraocular manifestations, best-corrected visual acuity, slit-lamp biomicroscopy, retinal examination, retinal photographs and fluorescein angiograms. We sought features that correlated with the visual outcome. · Results: Thirty of 75 (40%) patients developed subretinal fibrosis. Eleven patients (14.7%) had choroidal neovascularization. Presence of subretinal fibrosis was associated with a longer duration of the disease (42.6 vs 19.1 months, P=0.07). Patients with subretinal fibrosis had worse visual acuity than those without subretinal fibrosis (26.2 vs 57.3 ETDRS letters read, P<0.001) after adjusting for duration of disease (P=0.021), degree of vitreous haze (P=0.074), and use of immunosuppressive therapy (P=0.008). · Conclusions: Presence of subretinal fibrosis in patients with VKH is associated with a poor visual prognosis. The diagnosis of choroidal neovascularization and subretinal fibrosis presents a challenge in the management of this disease. Received: 10 June 1999 Revised version received: 4 August 1999 Accepted: 10 August 1999     

Quantitative visual fields under binocular viewing conditions in primary and consecutive divergent strabismus

· Background: Although there have been a number of studies on the size of the suppression scotoma in divergent strabismus, there have been no reports on the full extent (i.e. size as well as depth) of this scotoma. · Methods: Binocular static perimetry was used to measure suppression scotomas in five patients with primary divergent strabismus and ten patients with consecutive divergent strabismus. Four control subjects were also included in the study. With two modified Friedmann visual field analysers, we measured the visual field of both eyes under monocular and binocular viewing conditions. The objective angle of squint ranged from 3° to 25°. Best corrected visual acuity was at least 0.4, but mostly 1.0 in both eyes. · Results: All subjects had normal visual fields for each eye under monocular viewing conditions. In 12 of the 15 subjects, we found a large area of suppression encompassing the projection of the fixation point as well as that of the fovea in the non-fixating eye under binocular viewing conditions. In 2 of these 12 patients, one with primary and one with consecutive divergent strabismus, the area of suppression was located nasally to the postion of the fovea in the field of the non-fixating eye (nasal hemisuppression). In another two patients with divergent squint combined with vertical deviation, a small fixation-point suppression scotoma was found. The depth of suppression ranged from 3 dB to 16 dB. In one subject only, no suppression was found. · Conclusions: Our findings indicate that the shape of the suppression scotoma is not related to the origin of divergent strabismus or to the angle of squint. Our results also indicate that the critical age for the development of suppression in divergent squint might be up to 14 years. Received: 23 June 1998 Revised version received: 14 September 1998 Accepted: 15 October 1998     

Long‐term results of the effect of intravitreal ranibizumab on the retinal arteriolar diameter in patients with neovascular age‐related macular degeneration

Purpose: To study the effect of intravitreal (IVT) ranibizumab on the retinal arteriolar diameter in patients with neovascular age‐related macular degeneration (AMD). Methods: Ten eyes of 10 patients with previously untreated neovascular AMD were included. All eyes had three monthly IVT injections of ranibizumab and then were retreated as needed, based on visual acuity and optical coherence tomography (OCT) criteria. The diameter of the retinal arterioles was measured in vivo with a retinal vessel analyser (RVA) before the first IVT injection, 7 and 30 days after the first, the second and the third injection, and at month 12 of follow‐up. Results: A significant vasoconstriction of the retinal arterioles was observed following each one of the first three IVT injections of ranibizumab. Thirty days following the first, second and third injection, there was a mean decrease of 8.4 ± 3.2%, 11.9 ± 4.5% and 18.5 ± 7.2%, respectively, of the retinal arteriolar diameter compared with baseline (p < 0.01). At month 12, the vasoconstriction was still present with a mean decrease of 19.1 ± 8.3% of the retinal arteriolar diameter compared with baseline (p < 0.01). Median number of ranibizumab injections was 4 (range 3–10). There was no correlation between the number of injections and percentage diameter decrease at month 12 (r = ?0.54, p > 0.1). There was no significant change in mean arterial pressure (MAP) during the period of follow‐up (p > 0.05). Conclusions: These results suggest that IVT ranibizumab induces sustained retinal arteriolar vasoconstriction in eyes with neovascular AMD.     

Anatomic–Functional Correlates in Lesions of Retinal Vein Occlusion

PurposeTo evaluate anatomic–functional associations at sites of retinal lesions in retinal vein occlusion (RVO).MethodsThis pilot, prospective, observational study was conducted at the Northern Ireland Clinical Research Facility (NICRF) of Queen''s University and the Belfast Health and Social Care Trust, Northern Ireland, between August 1, 2018, and September 30, 2019. The study included 10 treatment-naïve patients with RVO (10 RVO eyes and 10 fellow eyes). There were 81 points/sites assessed for each eye at baseline; six patients were re-assessed 6 months after anti-vascular endothelial growth factor therapy at the same locations. We investigated associations between retinal sensitivity and presence of structural RVO lesions, including retinal ischemia, hemorrhages, intraretinal fluid (IRF) and subretinal fluid outside the foveal/parafoveal regions. Comparisons were made between RVO eyes and fellow eyes at baseline, and between RVO eyes at baseline and at 6 months after treatment. Regression models were used to investigate anatomic–functional associations.ResultsAt baseline, strong associations were found between reduced retinal sensitivity and presence of ischemia (estimate = −2.08 dB; P < 0.001), intraretinal fluid (estimate = −7.82 dB; P < 0.001), and subretinal fluid (estimate = −8.66 dB; P < 0.001). Resolution of subretinal fluid but not intraretinal fluid was associated with improved function (estimate = 2.40 dB [P = 0.022]; estimate = 1.16 dB [P = 0.228], respectively). However, reperfusion of ischemic retina, observed in 31 of 486 points (6%) 6 months after anti-vascular endothelial growth factor therapy, was associated with a further decrease in retinal sensitivity (estimate = −2.34 dB; P = 0.035).ConclusionsRetinal sensitivity was decreased at sites of RVO lesions. Decreased function at sites of retinal ischemia did not recover after treatment, even when reperfusion occurred.     

Long-Term Outcomes in Patients with Neovascular Age-Related Macular Degeneration Who Maintain Dry Macula after Three Monthly Ranibizumab Injections

Purpose: To evaluate long-term changes in visual acuity and retinal microstructure in patients with neovascular age-related macular degeneration (AMD) who had maintained dry macula after initial treatment. Methods: This retrospective observational study included 55 eyes that were diagnosed with neovascular AMD, were treated with three monthly ranibizumab injections, and maintained dry macula during a two-year follow-up. Best-corrected visual acuity (BCVA) at three months and at the final follow-up were compared, and the degree of visual improvement was compared between eyes with and without improvement of the ellipsoid zone. In addition, the incidence of improvement of the ellipsoid zone was compared between eyes with different extents of disruption. Results: The mean follow-up period was 30.3 ± 4.1 months. BCVA at three months and at the final follow-up was 0.51 ± 0.46 and 0.45 ± 0.49 (P<0.001). Among 35 eyes that exhibited >200 μm of disruption of the ellipsoid zone, 15 (42.9%) showed improvement of the ellipsoid zone, and the improvement in BCVA was greater in these eyes than that in the remaining 20 eyes (P=0.021). A higher incidence of improvement of the ellipsoid zone was noted in eyes with 200 to 800 μm of disruption than in eyes with >800 μm of disruption (P<0.001). Conclusions: Long-term improvement in visual acuity was noted in eyes that had maintained dry macula after three ranibizumab injections. The status of the ellipsoid zone at three months was closely associated with visual improvement.     

Symmetry of disciform scars in bilateral age-related macular degeneration.

The size of the final macular scar in subretinal neovascularisation (SRNV) is one of the most important determinants of final visual function in patients with subfoveal disease. We studied patients with bilateral macular scars from age-related subretinal neovascular membranes retrospectively in order to determine whether or not fellow eyes behave similarly. We found a significant correlation between eyes in terms of final scar size (r = 0.50, p less than 0.01). We found that 50% of fellow eyes with large macular scars (greater than 3 x 10(6) microns2) had similar sized lesions, while only 16% of fellow eyes with small macular scars (less than 0.5 x 10(6) microns2) had large scars (p less than 0.01). We discuss the significance of these findings in relation to the pathogenesis of subretinal neovascular membranes, and their implications for treatment.     

Efficacy of intravitreal bevacizumab (Avastin®) therapy for early and advanced neovascular age‐related macular degeneration

Purpose: To evaluate the safety and efficacy of intravitreal bevacizumab therapy for early and advanced neovascular age‐related macular degeneration (ARMD). Methods: A consecutive series of eyes with neovascular ARMD treated with monthly intravitreal injections of bevacizumab (1.25 mg/0.05 ml) as long as there was evidence of activity on fluorescein angiography (FA) and optical coherence tomography (OCT) was included and observed for 6 months. For further analysis they were assigned to either an early (untreated/newly diagnosed) or an advanced (predominantly fibrotic/pre‐treated) ARMD group. We examined distance visual acuity (VA) with Early Treatment Diabetic Retinopathy Study (ETDRS) charts and central retinal thickness with OCT, as well as lesion size and safety aspects. Results: Forty‐four patients (44 eyes) were enrolled (21 early lesions, 23 advanced lesions). Mean VA changed from 0.74 logMAR at baseline to 0.68 logMAR at month 6 (P = 0.01). Improvement in VA was statistically significant only in eyes with early lesions (n = 21) from month 1 (P = 0.015) up to month 6 (P = 0.03). The changes in central retinal thickness (CRT) (P < 0.001) and total lesion size (P < 0.001) were significant in both groups (early and advanced) at all time‐points during follow‐up. No significant ocular or systemic adverse effects were observed. Conclusion: Intravitreal bevacizumab was tolerated well by our patients and we did not identify any apparent short‐term safety concerns. We observed stabilization in VA overall, with significant improvement in the early lesion group.     

Functional evaluation of the macular area in early glaucoma using microperimetry

Purpose:To evaluate the central visual field by microperimetry (MP), in early glaucoma.Methods:Consecutive perimetrically experienced patients with a single nasal step or arcuate scotoma and 14 control eyes underwent MP. Retinal sensitivity on MP was mapped for frequency and depth of loss in the central 10° around fixation.Results:Twenty-one eyes had a single nasal step and 19 eyes with single arcuate scotoma on standard automated perimetry (SAP), with central 10° being normal on 30–2 and 10–2 perimetry. The average mean sensitivity on MP, in glaucomatous and control eyes was 11.8 ± 3.9 dB and 16.6 ± 1.2 dB, respectively, P = 0.0004. The average mean defect on MP-1, in glaucomatous and control eyes was - 6.5 ± 2.0 dB and - 3.0 ± 1.2 Db, respectively, P = 0.05. The corresponding retinal hemisphere showed significant defects in MP. In eyes with single nasal steps, an absolute scotoma was seen in 14–28% of eyes 8–10° off fixation, moderate to mild defects were seen in 10–52% eyes, and 10% eyes showed involvement up to 4° from the fixation. Eyes with arcuate scotoma had an absolute scotoma on MP in 95% of eyes, 6–10° from fixation, with extension up to 2° from fixation in 21%. In glaucomatous eyes, the normal hemisphere on SAP showed a mild defect on MP in 43%. Control eyes did not show any defect in SAP or MP.Conclusion:A significant loss of central retinal sensitivity is recorded on MP in early glaucomatous neuropathy as compared to SAP. Paramacular absolute defects were seen at 6–10° from fixation.     

Correlation of quantitative three-dimensional measurements of macular hole size with visual acuity after vitrectomy

· Objective: The purpose of the study was to study the relationship of postoperative visual outcome with anatomical parameters of macular holes using confocal scanning laser tomography and to predict the postoperative visual results. · Design: Cohort study. · Intervention and participants: We evaluated the eyes of 44 patients undergoing macular hole surgery (10 men and 34 women aged 40–76 years, mean 59.1 years). All patients showed idiopathic full-thickness stage 3 macular holes. The duration of symptoms was 1–4 months (mean 2.7 months). · Main outcome measures: The area, volume, mean depth, and maximum depth of the macular holes and the areas of cuff and retinal striae were measured using the Heidelberg Retina Tomograph preoperatively. · Results: All 44 eyes showed closure of the holes and flattening of cuff and retinal striae after vitrectomy and gas tamponade. Postoperative visual acuity was significantly correlated with the area (r=0.822, P<0.0001), volume (r=0.840, P<0.0001), mean depth (r=0.842, P<0.0001), and maximum depth (r=0.831, P<0.0001) of the macular holes, area of cuff (r=0.625, P<0.0001), and area of retinal striae (r=0.648, P<0.0001 ). Multiple regression analysis showed that the combination of the preoperative mean depth of macular holes and logarithm of preoperative visual acuity was the strongest predictor of the postoperative visual acuity. · Conclusions: Postoperative visual results vary significantly with the size of macular holes in patients with stage 3 macular holes of duration 1–4 months. The use of the confocal scanning laser tomography may facilitate the evaluation of macular holes before surgery. Ability to predict the postoperative visual results would be helpful in treating patients with macular holes. Received: 24 July 1998 Revised version received: 30 September 1998 Accepted: 1 October 1998     

Correlation of structural retinal nerve fibre layer parameters and functional measures using Heidelberg Retinal Tomography and Spectralis spectral domain optical coherence tomography at different levels of glaucoma severity

Background: To compare the structure/function relationship in glaucoma cases at different levels of severity, and with different disc sizes, between the Heidelberg Retinal Tomography and Spectralis spectral domain optical coherence tomography. Design: Retrospective study of glaucoma patients attending a Sydney‐based private practice. Participants: 169 eyes of 169 patients with a clinical diagnosis of glaucoma. Methods: Patients were divided on visual field criteria into early (mean deviation > –4 dB), moderate (–4 dB < mean deviation < –10 dB) and severe (mean deviation < –10 dB) disease. Bivariate correlation (Spearman's rho) between mean threshold scores for each area and the corresponding mean retinal nerve fibre layer thickness sectoral measurement were calculated. Main Outcome Measures: Correlation, as measured by Spearman's rho, between retinal nerve fibre layer measurements and mean threshold scores. Comparison of correlation strengths between the two scanning modalities with analysis of the effect of disease severity and disc size. Results: Both imaging techniques showed only moderate correlations at best. Spectral domain optical coherence tomography (global retinal nerve fibre layer Spearman's rho = 0.670, P < 0.01) had higher correlation coefficients compared with Heidelberg Retinal Tomography rim area (Spearman's rho = 0.449, P < 0.01) and retinal nerve fibre layer (Spearman's rho = 0.421, P < 0.01). Disc size did not have a significant influence on the structure/function relationship. Conclusions: Spectral domain optical coherence tomography retinal nerve fibre layer measurements demonstrated closer correlations to visual field threshold reductions using a structure/function model in varying stages of glaucoma.     

Changes in retinal sensitivity in patients with neovascular age-related macular degeneration after systemic bevacizumab (avastin) therapy

OBJECTIVE: To evaluate changes in central retinal sensitivity in patients with neovascular age-related macular degeneration after systemic bevacizumab (Avastin; Genentech, Inc., South San Francisco, CA) therapy. METHODS: For all eyes, the central 12 x 12 degrees visual field was recorded using the MP 1 Microperimeter (Nidek, Gamagori, Japan) at baseline and 1 week, 1 month, 3 months, and 6 months after initial treatment. Patients received systemic anti-vascular endothelial growth factor (VEGF) therapy with three initial bevacizumab infusions at 2-week intervals. Retreatment during follow-up was performed only in cases of choroidal neovascularization recurrence. Seven patients (12 eyes) received bevacizumab infusions at a dose of 5 mg/kg, and 7 patients (9 eyes), at a dose of 2.5 mg/kg. RESULTS: Of 41 stimulation points, a mean absolute scotoma of 15 missed stimulation points was measured at baseline, which decreased to 10 missed stimulation points at month 3 (-5; P = 0.005) and to 11 stimulation points at month 6 (-4; P = 0.106). The mean absolute scotoma size (in % of total tested area) decreased from 33% to 22% (-11%; P = 0.011) at month 3 and to 23% (-10%, P = 0.123) at month 6. Mean differential light threshold increased significantly throughout the observation period from 3.8 dB at baseline to 5.5 dB (+1.7 dB; P = 0.012) at month 6. CONCLUSIONS: Systemic bevacizumab therapy induced a significant increase in mean retinal sensitivity at month 6 of follow-up and a significant decrease of mean absolute scotoma size at month 3. The MP 1 Microperimeter proved to be a valuable tool in the evaluation of functional benefits and retinal safety of anti-VEGF therapy with systemic bevacizumab.     

A prospective study on intravitreal bevacizumab (Avastin®) for neovascular age‐related macular degeneration of different durations

Purpose: Choroidal neovascularization (CNV) accounts for 85–90% of severe visual impairment in age‐related macular degeneration (AMD). Vascular endothelial growth factor (VEGF) is a major factor mediating angiogenesis, and VEGF inhibitors have become a new treatment modality. In this prospective study, we used bevacizumab (Avastin^®), a recombinant monoclonal antibody to VEGF, to treat neovascular AMD. Methods: The case material comprised 36 subjects (26 females, 10 males) aged 65–88 years with subfoveal neovascular AMD with all subtypes of CNV. There were two categories of patients: category I, long‐standing CNV (12 months or more), preoperative visual acuity (VA) 0.16 (mean); category II, CNV (duration <12 months), preoperative VA 0.25 (mean). Evaluation protocol included the Early Treatment Diabetic Retinopathy Study (ETDRS) VA, clinical ophthalmological examination, fluorescein angiography and optical coherence tomography (OCT). Intravitreal injections of bevacizumab (Avastin^®) (IVB), 1.25 mg (0.05 ml), were given under an operating microscope and aseptic conditions in a theatre for surgery with intervals of 4 or 6 weeks during the first 3 months and subsequently according to clinical assessment. The follow‐up was 6 months in all cases. Results: At 6 months, mean VA had improved by 4.6 ETDRS letters in the entire case material (P = 0.001), by 3.9 letters in category I (duration 12 months or more) and by 6.0 letters in category II (duration <12 months). A total of 148 IVB (mean 4.1 injections/eye) were delivered during 6 months, the first 3 months comprising 3.1 IVB (mean) and the last 3 months 1.0 IVB (mean). No eyes suffered visual decline of 15 ETDRS letters. Fluorescein angiograms displayed stabilization or regression of CNV activity; OCT showed resorption of intraretinal oedema and subretinal fluid. No severe complications occurred but recurrence was common, and repeated IVBs were necessary in most cases during the 6‐month period. Conclusion: When addressing the issue of frequency of IBV, we observed that 6‐week intervals were sufficient because VA and CNV lesions generally stabilized at 4 weeks. The gain in VA was promising in eyes with <12 months CNV duration. Even in eyes with a longer CNV duration, a slight visual improvement was observed when retinal oedema resorbed, although subretinal fibrosis and general cellular damage certainly limited recovery.     

Combined Special Capsular Tension Ring and Toric IOL Implantation for Management of Astigmatism and High Axial Myopia with Cataracts

Aim: This study aimed to compare the effects of toric intraocular lens (IOL) implantation with a capsular tension ring and toric IOL implantation only in patients with axial myopic astigmatism who had undergone cataract surgery. Methods: Of 34 patients with axial myopia, 16 patients who had received IOL and capsular tension ring (CTR) implantation were included in the combined group and 18 patients who received toric IOL implantation only were included in the simple group. Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA) were evaluated by measuring subjective refraction, residual astigmatism, and the toric IOL axis six months post-surgery. Results: At six months postoperatively, the UCVA for the combined and simple groups was 4.6 ± 0.1 and 4.5 ± 0.2, respectively, a statistically significant difference (t = 3.531, P<0.05). The toric IOL in all of the cases was located in the capsular sac, but there were more cases with IOL rotation (12 eyes) in the simple group than in the combined group (4 eyes). The rotation angles were 20°~30° (one eye), 10°~20° (four eyes), and <10° (seven eyes) compared with 2°~5° (four eyes). The residual astigmatism was –0.50 ± 0.25 D in the combined group, not a significant difference from the predicted residual astigmatism (–0.35 ± 0.13 D). There was a significant difference in the simple group (–1.25 ± 0.33 D) when the predicted residual astigmatism was compared (–0.37 ± 0.11 D) (t = –9.511, P < 0.01). Conclusions: In patients with axial myopic astigmatism, CTR can effectively increase the rotational stability of a toric IOL, achieving improvement in corneal astigmatism and visual acuity.     

Normalization of generalized retinal function and progression of maculopathy after cessation of therapy in a case of severe hydroxychloroquine retinopathy with 19 years follow-up

A 40-year-old Caucasian female was first seen 20 years ago for a routine ocular screening in relation to hydroxychloroquine treatment for systemic lupus erythematosus. Her daily dose was 600 mg (or 12 mg/kg of body weight/day) of hydroxychloroquine. Three years later, she complained of mild visual loss in the right eye. Her best-corrected visual acuity was 0.9 in the right (RE) and 1.0 in the left eye (LE). In addition, she had a central scotoma (RE > LE) on automated visual field analysis (Humphrey central 30°). On fundoscopy and fluorescein angiography, the first signs of a bilateral bull’s eye maculopathy were detected. A decreased Arden ratio on EOG (<1.50) was found with an accompanying decreased amplitude of the scotopic b-wave on full-field electroretinography in both eyes. Consequently, the treatment was immediately stopped. During the following years, the patient was retested regularly. After more than 18 years after cessation of the drug, most tests showed a further deterioration, including best-corrected visual acuity (RE: 0.1; LE: 0.7). On visual field testing, a progressive evolution to a total and absolute central scotoma in the RE (central 10°) and an annular scotoma in the LE became apparent. In contrast, a partial recovery of the Arden ratio of the EOG to 1.8 in both eyes was seen. In addition, a partial recovery of the scotopic b-wave full-field ERG was noted 19 years after cessation of treatment. At retest visits respectively 18, 19 and 20 years after cessation of hydroxychloroquine, a multifocal electroretinogram was performed in combination with colour vision tests and contrast sensitivity measurements.     

The effect of mitomycin C trabeculectomy on the progression of visual field defect in normal-tension glaucoma

Background: We investigated in a prospective fashion the visual prognosis and complications in normal-tension glaucoma following unilateral trabeculectomy with adjunctive mitomycin C. Methods: Trabeculectomy with adjunctive mitomycin C was carried out unilaterally in 21 cases of normal-tension glaucoma. Intraocular pressure (IOP), visual prognosis, and complications were compared between the operated eyes and the non-operated fellow eyes. The follow-up period ranged from 2 to 7 years. Results: The IOP dropped significantly from 14.8±1.8 mmHg (mean ± SD) to 9.6±3.9 mmHg in the operated eyes (P=0.0002, Wilcoxon signed-rank test ), but did not drop in the non-operated eyes. The mean deviation (MD) was –12.69±6.41 dB preoperatively and –14.70±5.49 dB at the last clinic visit in the operated eyes, whereas in non-operated eyes it was –7.85±5.65 dB and –11.15± 5.62 dB, respectively. The MD deteriorated significantly in both operated and non-operated eyes (operated eyes P=0.0239, non-operated eyes: P=0.0002; Wilcoxon signed- rank test). The MD slope was –0.37±0.60 dB/year and –0.71± 0.89 dB/year for the operated and non-operated eyes, respectively (P=0.5243, Mann-Whitney U-test). Visual field deterioration was more frequently observed in the non- operated eyes by a pointwise definition of the progression (P<0.05, McNemar test). Visual acuity deteriorated in 6 of the operated eyes and in 5 of the non-operated eyes. Cataract developed in 6 (29%) of the 21 operated eyes, while among the non-operated eyes 4 (19%) developed cataract. Conclusion: Mitomycin C trabeculectomy is effective in delaying progression of visual field defect in normal-tension glaucoma, but complications may arise and cause some visual disturbance. Received: 4 May 1999 Revised version received: 4 August 1999 Accepted: 16 August 1999     

Predictive value of pattern VEP, pattern ERG and hole size in macular hole surgery

· Objective: To describe pattern-reversal visual evoked response (PRVEP) and pattern electroretinogram (PERG) parameters in eyes with macular hole and their value for predicting postoperative visual outcome. · Methods: Prospectively we studied 27 eyes (27 patients) with a full-thickness macular hole. Preoperatively the hole and rim were measured and the PRVEP and PERG were recorded. The preoperative parameters were correlated with postoperative visual outcome. · Results: The macular hole was closed in 26 of 27 eyes. Sixteen eyes (59%) had an increase in visual acuity (VA) of two lines or more, 10 eyes (37%) remained within one line of preoperative VA and 1 eye (4%) had a decrease in VA of two lines. Duration of symptoms was negatively correlated with preoperative VA (R=–0.547, P=0.0038) and postoperative VA (R=–0.519, P=0.0065) and positively correlated with hole area (R=0.533, P=0.0061) and rim area R=0.633, P=0.0009). Only the PRVEP P100 latency of the 10′ check size and the PERG N35 latency were significantly associated with visual outcome (P=0.022 and P=0.042 respectively). · Conclusions: There was no association of either hole or rim size with postoperative visual outcome. Preoperative electrophysiology, however, is useful as a prognostic tool. Utilization is limited to the use of latency parameters of the response and is dependent on the check size of the stimulus. Received: 3 November 1998 Revised version received: 8 January 1999 Accepted: 19 January 1999     

Organic visual loss measured by kinetic perimetry and retinal electrophysiology in children with functional amblyopia

Purpose

To demonstrate an organic (retinal) amblyogenic defect in functional amblyopes not responding to treatment.

Methods

Twenty-four children (Mean age: 5.9?±?1.8 years; range: 4–10 years) with functional amblyopia were recruited for this study. All these children underwent complete ophthalmic and orthoptic evaluation. In addition, Kinetic Goldman Visual Fields (KGVF), Spectral Domain Optical Coherence Tomography (SD-OCT), full field flash electroretinograms (ffERG) and multifocal electroretinograms (mfERG) were also performed. Ratios were subsequently derived by comparing the amplitudes obtained from the amblyopic eye (AE) to the good eye (GE) for the a- and b-waves of the ffERG, as well as for the ring analysis of the mfERG.

Results

KGVF showed a central scotoma of varying size (3°–7°) and density (absolute to relative), with increasing target size in 14/24 patients whose best post-treatment vision in the AE ranged from 20/100 to 20/40. The scotoma decreased in size and density with improving vision until a plateau of recovery was reached. The remaining 10/24 patients with a vision?≥?20/30 showed no scotoma. SD-OCT showed no significant difference between the AE and GE. ffERG and mfERG were obtained in 18/24 patients. The ffERG AE/GE ratio was abnormal in 7 patients, 5 of which had large scotomas on KGVF. The mfERG ring 1 AE/GE ratio was significantly (p?<?.05) attenuated in 9/18 patients out of which 3 were no longer amblyopic. However, there was no significant difference (p?>?.05) in ring 1 AE/GE amplitude ratio between those who achieved 20/50–20/40 (.81?±?.26) and those with?≥?20/25(.86?±?.25).

Conclusions

The combined findings of central scotoma on KGVF and mfERG anomalies in patients who did not achieve optimal vision with treatment suggest an underlying organic defect impairing macular function.

     

Combined use of SLO microperimetry and OCT for retinal functional and structural testing

Background This study compared SLO microperimetry scotoma size measurements with the sizes of lesions assessed with OCT in the areas of scotoma.Methods SLO microperimetry was performed on eight patients to assess the location and extent of scotoma areas. An SLO microperimetry master image was used to localize the scotoma areas in the real time OCT fundus image and to center OCT cross scans on the areas of scotoma. The sizes of the morphological changes measured by OCT were compared with the scotoma size measurements.Results In each patient, OCT revealed a morphological change located in the area of scotoma. Scotoma sizes ranged from 465 to 3180 μm horizontally and from 570 to 2550 μm vertically. The corresponding lesion sizes ranged from 461 to 2660 μm horizontally and from 523 to 2282 μm vertically. The average difference between SLO and OCT measurements was 2.4% horizontally and 4.9% vertically. There were significant correlations between horizontal and vertical SLO and OCT measurements (Horizontal: R _sq=0.955, P<0.0001; Vertical: R _sq=0.898, P=0.0003).Conclusion SLO microperimetry scotoma size measurements and OCT lesion size measurements are similar to each other. Combining retinal functional testing with morphological testing provides information about the underlying causes of scotoma.     

Correlation between components of newly diagnosed exudative age‐related macular degeneration lesion and focal retinal sensitivity

Purpose: To analyse lesion components determining retinal sensitivity in microperimetry in eyes with newly diagnosed exudative age‐related macular degeneration (AMD). Methods: Visual acuity, contrast sensitivity, microperimetry, optical coherence tomography (OCT), and fluorescein (FA) and indocyanine green (ICGA) angiographies of 23 eyes of 23 patients were analysed. Central microperimetry grids with 28 test stimulus sites were automatically aligned with three‐dimensional OCTs and manually aligned with angiographies. Thicknesses of the neuroretina, neuroepithelial detachment (NED), retinal pigment epithelial (RPE) elevation and subretinal tissue were measured under the 644 microperimetry stimulus sites. Areas of classic and occult choroidal neovascularizations (CNVs), subretinal and intraretinal haemorrhage, and late hyperfluorescence in ICGA were identified. The impact of the lesion components on retinal sensitivity was evaluated with correlation analysis and multivariate modelling. Results: Decreased retinal sensitivity correlated significantly with the presence of CNV, haemorrhage, subretinal tissue and RPE elevation. Out of the OCT parameters, the most important determinant of sensitivity was the thickness of RPE elevation (Spearman’s rho, r = ?0.202, p < 0.0001). The thicknesses of subretinal tissue (r = ?0.168, p < 0.0001) and NED had weaker effects (r = ?0.147, p < 0.0001), and the neuroretinal thickness remained nonsignificant. In multivariate modelling, RPE elevation and subretinal tissue in OCT, CNV membranes in angiographies and haemorrhage had the strongest impacts on retinal sensitivity. Conclusion: The most important lesion components affecting retinal function were RPE elevation and subretinal tissue in OCT as well as neovascular membranes and haemorrhage in angiographies. NED and neuroretinal thickening remained less significant.