Evaluation of macular abnormalities in Stargardt’s disease using optical coherence tomography and scanning laser ophthalmoscope microperimetry

Background  The purpose of this study is to evaluate the diagnostic value of optical coherence tomography (Stratus OCT) and scanning laser ophthalmoscope (SLO) microperimetry in patients with Stargardt’s disease (STGD), and the correlation between macular morphology and visual function in these patients. Methods  Twenty-two patients with STGD (mean age 44 years, range 11 to 71 years) and 20 age-matched healthy control subjects were included in the study. OCT imaging was performed using six radial line scans manually centered on the fovea. SLO microperimetry was used to assess central scotoma and fixation behavior in patients with STGD. Results  Mean best corrected Snellen visual acuity (BCVA) was 20/80, range 20/25 to 20/300 (log MAR 0.6, range 0.1 to 1.2) in the STGD group and 20/20 (log MAR 0.0) in the control group. Foveal thickness was significantly reduced in patients with STGD (119.0 ± 19.6 μm) compared to controls (210.7 ± 19.6 μm, P < 0.0001). A significant correlation between foveal thickness and BCVA was observed within the STGD group (R² = 0.62, P < 0.0001). Photoreceptor loss in the macular area and a corresponding central scotoma were observed in all STGD patients. Conclusions  OCT findings, particularly reduced foveomacular thickness and photoreceptor loss in the macular area may be useful in the diagnosis of STGD. Furthermore, a strong correlation between foveal thickness and visual function was observed in our patients. Assessment of central visual function using SLO microperimetry provides additional useful information, important in the management of STGD.     

A Microperimeter That Provides Fixation Pattern and Retinal Sensitivity Measurement

Purpose

To investigate a microperimeter (MP-1) that can independently measure fixation status and microperimetry of retinal threshold sensitivity by comparing the results obtained by the MP-1 with those obtained by scotometry using scanning laser ophthalmoscopy (SLO).

Methods

Fourteen patients (15 eyes) with a macular disorder were examined by the MP-1 fixation test, MP-1 microperimetry, and SLO scotometry. The scotoma size seen in MP-1 microperimetry was compared with that observed in SLO scotometry. The location of the preferred retinal locus (PRL) and the fixation stability, which were obtained from the fixation test in MP-1, were also compared with those obtained in SLO scotometry.

Results

The scotoma size, which was not seen with 0?dB in MP-1 microperimetry, was larger than that in SLO scotometry in 8 of the 15 eyes. Retinal threshold sensitivity decreases were found using MP-1 microperimetry within a sensitive area of SLO scotometry in all eyes. The PRL in the MP-1 fixation test and in SLO scotometry agreed in all eyes. Fixation stability in the MP-1 fixation test significantly correlated with that in SLO scotometry (P = 0.0192).

Conclusions

The results of MP-1 microperimetry do not completely agree with those of SLO scotometry owing to the difference in stimulus intensity. The MP-1 fixation test is useful for measuring PRL and fixation stability in a short time. MP-1 might be helpful to evaluate the foveal function in patients with macular disorders without severely damaged macular function.?Jpn J Ophthalmol 2006;50:111–115 © Japanese Ophthalmological Society 2006     

SLO-mfERG-Kampimetrie und SLO-Mikroperimetrie bei Morbus Stargardt

PURPOSE. We used a scanning laser ophthalmoscope (SLO) evoked multifocal electroretinography (mf-ERG) to evaluate retinal function in patients with Stargardt's disease. SLO microperimetry could demonstrate the size of central retinal scotoma very well in these patients. The aim of the examination was to correlate the results of SLO mf-ERG and SLO microperimetry. METHODS. In four patients with Stargardt's disease SLO mf-ERG and SLO microperimetry were performed. The area of measurement in the SLO mfERG had a 24 degrees diameter (12 degrees visual angle) at the posterior pole of the eye. Stimulation was done using a helium-neon laser (632.8 nm). Simultaneous control of fixation was made using a infrared laser (730 nm). SLO microperimetry was performed with stimuli having the size of Goldmann III stimuli and the intensities 0 dB, 12 dB and 20 dB. In this study the reduction of SLO mfERG amplitudes was correlated to graded stimulus intensities in the SLO microperimetry. RESULTS. The area of reduced retinal function in the SLO mf-ERG measurement could be well correlated to the size of the scotoma in the SLO microperimetry, using the stimulus Goldmann III with the intensity 20 dB. CONCLUSION. SLO mfERG and SLO microperimetry are sensitive methods for quantifying functional deficits and are therefore useful for performing a detailed examination of the retina.     

Differentiating full thickness macular holes from impending macular holes and macular pseudoholes

AIMS—The reliability of scanning laser ophthalmoscope (SLO) microperimetry in differentiating full thickness macular holes from macular pseudoholes and impending macular holes was evaluated.
METHODS—106 eyes with the clinical diagnosis of full thickness macular holes, macular pseudoholes, and impending (stage 1) macular holes were examined for the presence of deep or relative scotoma using SLO microperimetry. The relation between these scotomas and the clinical diagnosis was studied.
RESULTS—Deep and relative scotomas were detected in all 57 eyes with clinically defined full thickness macular holes. In contrast, among 49 eyes diagnosed with macular pseudoholes or impending macular holes, no deep and only one relative scotoma was observed. The sensitivity of the presence of a deep scotoma as an indicator of the clinical diagnosis of a full thickness macular hole was 100% (57 of 57), and the specificity was 100% (49 of 49). The sensitivity of the presence of a relative scotoma was 100% (57 of 57) and the specificity was 98.0% (48 of 49).
CONCLUSION—With SLO microperimetry, full thickness macular holes can be precisely and objectively distinguished from other conditions that mimic macular holes.

     

Scotoma size reduction as an adaptive strategy in age-related macular degeneration

Objective: Retinal areas with reduced sensitivity to light stimuli represent the true scotoma size in patients with age-related macular degeneration (AMD), whereas the perceived visual field defect area that covers a specific target of regard may represent an effective size of the same scotoma. This study was designed to highlight the conceptual difference between the “true scotoma size” and its “effective scotoma size” counterpart.Design: Prospective nonrandomized observational case series.Participants: Ten adults with documented AMD, low vision, and best-corrected visual acuity of 20/50-20/200 in the better eye.Methods: Effective scotoma size and true scotoma size were calculated from measurements with the macular grid test performed with automated perimetry and from microperimetry performed with the Nidek MP-1, respectively.Results: Ten patients aged 70-92 years (mean 81 years) met the inclusion criteria. Mean effective scotoma size measured with the macular grid test was 40.19 (SD 34.88) deg². Mean true scotoma size measured with microperimetry was 75.17 (SD 56.08) deg² (p ≤ 0.003). The log unit change in scotoma size, defined as scotoma utility score, was −55.91%. The effect size observed for the scotoma utility score was 0.74.Conclusions: Effective scotoma size experienced by patients with AMD is significantly smaller than true scotoma size. This reduction may be explained by adaptive variability in eye positions during any single fixation stability attempt, which ultimately results in enhanced visual field perception.     

Correlation of retinal sensitivity with visual acuity and macular thickness in eyes with idiopathic epimacular membrane

The aim of this study was to analyze macular function by measuring the sensitivity of the macula with fundus-related microperimetry and to compare the results with the best corrected visual acuity (BCVA) and foveal retinal thickness measured by optical coherence tomography (OCT) in patients with idiopathic epimacular membrane. We prospectively reviewed 66 eyes with idiopathic epimacular membrane and 35 normal healthy eyes in patients who had undergone fundus-related microperimetry and OCT. The macular sensitivity was measured using the recently introduced fundus-related microperimeter, MP-1. The mean retinal sensitivities in the central 10° (central microperimetry, cMP-1) and in the paracentral 10–20° (paracentral microperimetry, pMP-1) areas were determined and correlated with the BCVA and OCT-measured foveal thickness. Eyes with epimacular membranes showed significantly lower log MAR BCVA (P < 0.001) and cMP-1 microperimetry sensitivity (P < 0.001) and significantly higher OCT foveal thickness (P < 0.001) than control eyes. There was a significant correlation between the BCVA and mean retinal sensitivity in the cMP-1 (r ² = 0.26, P < 0.001) and the pMP-1 (r ² = 0.07, P = 0.008) areas. A significant negative correlation was observed between the foveal thickness and the mean retinal sensitivity in the cMP-1 (r ² = 0.13, P < 0.001) area. Retinal sensitivity in the central macular area determined by MP-1 microperimetry was significantly correlated with BCVA and with foveal thickness. The combination of OCT and microperimetry may help a better evaluation of the patients with idiopathic epimacular membrane.     

Use of scanning laser ophthalmoscope microperimetry in clinically significant macular edema in type 2 diabetes mellitus

PURPOSE: We used scanning laser ophthalmoscope (SLO) microperimetry to evaluate scotomas in patients with clinically significant diabetic macular edema (CSME) in type 2 diabetes mellitus. METHODS: We studied 19 patients (mean age = 63 years; range, 45-78 years) (19 eyes). SLO microperimetry was performed in all eyes. We divided patients into three groups as follows: dense scotoma, relative scotoma, and no scotoma. The following variables were documented: age; duration of diabetes, hemoglobin A(1c) levels; logarithm of the minimum angle of resolution (Log(MAR)) visual acuity; refractive power; a history of panretinal photocoagulation; presence or absence of proliferative diabetic retinopathy, vitreomacular separation, and cystoid changes; the type of macular edema; and stability of fixation. All variables were compared in the three groups. RESULTS: We identified 4 eyes (21.1%) with dense scotoma, 10 (52.6%) with relative scotoma, and 5 (26.3%) with no scotoma. There were significant differences in log(MAR) visual acuity among those with dense scotoma (1.4 +/- 0.5), relative scotoma (0.6 +/- 0.2), and no scotoma (0.2 +/- 0.3) (P <.05), and in the prevalence of cystoid changes, diffuse edema, and unstable fixation among those with dense scotoma (75%, 75%, and 100%, respectively), relative scotoma (20%, 30% and 50%, respectively) and no scotoma (0%, 0% and 0%, respectively) (P <.05). CONCLUSIONS: Macular scotoma was observed by SLO microperimetry in 74% of the patients in this study. A scotoma in CSME is related to the formation of cystoid changes and the type of macular edema. In eyes with CSME in type 2 diabetes mellitus, a scotoma in the macula causes visual acuity impairment and unstable fixation.     

应用MAIA微视野计评估青光眼黄斑部功能改变

目的:观察青光眼患者微视野特征,探讨微视野检测值与最佳矫正视力(BCVA)、标准自动视野检测指标和光学相干断层扫描(OCT)检测指标的相关性。方法:病例对照研究。纳入青光眼患者45例76眼,其中原发开角型青光眼15例25眼,慢性闭角型青光眼30例51眼;正常对照组40例76眼。所有受检眼进行了MAIA微视野、Humphrey视野、BCVA检测,并与OCT测量的结构指标进行相关性分析。结果:青光眼患者与正常人群相比,微视野测出的黄斑平均光敏感度(MS)、OCT测出的神经节细胞复合体(GCC)、神经纤维层(RNFL)厚度低于正常对照组,Humphrey视野计10-2程序测出的视野平均缺损(MD)、GCC局部丢失体积(FLV)、GCC整体丢失体积(GLV)、63%双曲线椭圆面积(BCEA)高于正常对照组。青光眼组MS与MD、FLV、GLV、BCVA(LogMAR)呈负相关(r_s=-0.839、-0.665、-0.530、-0.424,均P<0.01)。青光眼组MS与GCC、RNFL呈正相关(r_s=0.437、0.500,均P<0.01)...     

Vitrectomy and internal limiting membrane peeling for myopic foveoschisis

PURPOSE: Myopic foveoschisis is common in high myopia. We report results of a pilot study of vitrectomy for patients with myopic foveoschisis. DESIGN: Interventional case series. METHODS: In an institutional setting five patients with high myopia (six eyes), and who had progressive visual impairment presumably due to myopic foveoschisis were studied. No eyes had a macular hole preoperatively based on optical coherence tomography (OCT). We performed vitrectomy including vitreous cortex removal, internal limiting membrane (ILM) peeling, and gas tamponade. Patients were followed for at least 6 months. Best-corrected visual acuity (BCVA), OCT. Scanning laser ophthalmoscope (SLO) microperimetry was examined in three eyes. RESULTS: The foveal detachment resolved completely in five eyes and partially in one eye. No serious complications developed including macular hole formation or retinal detachment; BCVA improved more than two lines in all eyes (100%) 6 months postoperatively (P <.01); SLO microperimetry showed smaller scotoma compared with preoperatively and stabilized fixation. CONCLUSIONS: Vitrectomy with vitreous cortex removal, ILM peeling, and gas tamponade could be useful to treat myopic foveoschisis in highly myopic eyes. Because the natural course of the disease is not well-understood, further study should establish indications for this surgery.     

Association of preoperative photoreceptor displacement and improved central scotoma after idiopathic macular hole surgery

OBJECTIVE: To investigate the relationship between preoperative photoreceptor displacement and postoperative scotoma after unilateral idiopathic macular hole surgery. DESIGN: Prospective nonrandomized comparative self-controlled trial. PARTICIPANTS: Twenty patients who underwent successful surgery for unilateral idiopathic macular hole participated in the study. METHODS: Kinetic perimetry using red and green filter glasses, black binocular fixation targets, and red and green selective monocular stimuli was performed preoperatively. Scanning laser ophthalmoscope (SLO) microperimetry was performed preoperatively and postoperatively. RESULTS: Sixteen patients had photoreceptor displacement preoperatively. In preoperative SLO microperimetry, all eyes with a macular hole had a scotoma; postoperatively, 12 of 16 had no scotoma. All four eyes with no preoperative photoreceptor displacement were noted to have a postoperative scotoma. The prevalence of postoperative scotoma in patients with preoperative photoreceptor displacement (4 of 16; 25%) was significantly lower than that in patients without preoperative photoreceptor displacement (4 of 4; 100%) (P = 0.03). CONCLUSIONS: The presence or absence of photoreceptor displacement preoperatively should affect postsurgical visual function. Photoreceptor damage may occur in eyes without photoreceptor displacement preoperatively, resulting in scotoma postoperatively.     

Detection of fenestrated central scotoma by scanning laser ophthalmoscope microperimetry in a patient with Leber’s hereditary optic neuropathy after visual recovery

Landmark-driven fundus microperimetry using a scanning laser ophthalmoscope (SLO) was performed to assess the local sensitivities of the central retina and to determine the fixation point in a patient with Leber’s hereditary optic neuropathy (LHON) after visual recovery. A 16-year-old Japanese boy was diagnosed as having LHON with an 11778 mutation of mitochondrial DNA. Fourteen months after starting idebenone and vitamin therapy, his vision began to recover and reached 1.0 in both eyes. His corrected visual acuity, Humphrey 10-2 threshold test, SLO microperimetry, critical flicker frequency (CFF), and visual evoked potentials (VEPs) were tested after visual recovery. At an early stage of visual recovery, the Humphrey 10-2 threshold test revealed a fenestrated scotoma in the right eye and a dense central scotoma in the left eye. SLO microperimetry of the left eye, however, detected a few spots that were sensitive to a stimulus intensity of 0 dB on the temporal side of the fovea. A fixation point was detected on the nasal side of the fovea and it was relatively stable in both eyes. CCF and VEPs deteriorated despite the recovery of vision in both eyes. The ability to detect small islands of vision and to identify fixation points are two advantages of SLO microperimetry over Humphrey perimetry.     

Anatomical and functional characteristics in atrophic maculopathy associated with spinocerebellar ataxia type 7

PURPOSE: To assess the anatomic and functional characteristics in a Korean family with spinocerebellar ataxia type 7-associated atrophic maculopathy. DESIGN: Observational case report. METHODS: Three patients in a family underwent funduscopic examination, fluorescein angiogram, full-field electroretinogram (ERG), electro-oculogram, and optical coherence tomography (OCT). Macular functions were assessed using multifocal ERG and scanning laser ophthalmoscope (SLO) microperimetry. RESULTS: Both eyes showed bull's eye configuration and cone-rod dystrophy phenotype. OCT revealed that retinal thinning extended outside the visibly atrophic lesions. Multifocal ERG demonstrated that amplitudes from the six ring segments were reduced in a centrifugal pattern. SLO microperimetry showed that fixations were unstable and shifted superior to the atrophic lesions. The areas of functional deficits were greater than those of anatomic deficits. CONCLUSIONS: Macular functions were severely depressed in atrophic maculopathy associated with spinocerebellar ataxia type 7 in both the visibly atrophic areas and the areas without visible atrophy in a centrifugal pattern.     

Scanning laser ophthalmoscopic microperimetry on idiopathic epiretinal membrane and vitreomacular traction syndrome

PURPOSE: To evaluate visual function before and after vitrectomy for idiopathic epiretinal membrane and vitreomacular traction syndrome. METHODS: Microperimetry with scanning laser ophthalmoscope (SLO) was performed in 4 eyes with idiopathic epiretinal membrane (IERM) and 2 eyes with vitreomacular traction syndrome (VMTS), before and at least 3 months after vitrectomy. RESULTS: Five eyes had preoperative scotoma, which disappeared postoperatively. In 1 eye, absolute and relative scotomas developed postoperatively over the areas where the retinal surface was vigorously scratched to peel off an overlying membrane, and in another eye new scotomas appeared over a newly formed epiretinal membrane 8 months after vitrectomy. CONCLUSIONS: To our knowledge, the present report is the first to describe preoperative absolute scotoma in IERM, VMTS and also iatrogenic absolute scotoma due to retinal scratching. SLO microperimetry is useful for evaluation of visual function before and after vitrectomy for epiretinal membrane and vitreomacular traction syndrome.     

Effects of verteporfin therapy on central visual field function

PURPOSE: To evaluate the effect of photodynamic therapy with verteporfin on the maintenance of central visual field function. DESIGN: Randomized controlled clinical trial. PARTICIPANTS: Forty-six consecutive patients with subfoveal choroidal neovascularization (CNV) caused by age-related macular degeneration including a classic component were randomly assigned. Thirty-three participants received standard verteporfin therapy, and 13 received placebo and laser treatment. METHODS: The trial was performed as a single-center, double-masked study. Patients were examined before therapy and continuously in 3-month intervals during 2 years of follow-up. A scanning laser ophthalmoscope (SLO) was used to perform macular microperimetry. Absolute and relative scotomas were documented at each visit, and size was measured in square millimeters. MAIN OUTCOME MEASURES: The change in size of central scotoma in the verteporfin group compared with the placebo group. RESULTS: An absolute scotoma was seen in 88%, and a relative scotoma was seen in 100% of eyes before therapy. Absolute defects were associated with the classic CNV component localized angiographically. In the verteporfin group, the absolute scotoma grew from 2.5 mm(2) at baseline to a final size of 7.3 mm(2) at month 24. In the placebo group, the mean lesion size of the absolute scotoma enlarged from an initial size of 2.7 mm(2) to 31.5 mm(2) after 24 months. The relative scotoma increased from 7.9 mm(2) at baseline to 20.8 mm(2) at month 24 in the verteporfin group, whereas a progression from 8.5 mm(2) initially to 48.3 mm(2) at the final presentation was measured in the placebo group. Statistical analysis showed that both the mean absolute and relative scotoma sizes were significantly smaller in the verteporfin group than the placebo group for all intervals from 6 to 24 months (P<0.001). CONCLUSIONS: Documentation of macular function with SLO perimetry demonstrated a significant benefit of verteporfin therapy for the preservation of the central visual field. Absolute and relative scotoma sizes remained smaller after therapy. This may influence reading ability and visual rehabilitation.     

Scanning Laser Ophthalmoscopic Microperimetry on Idiopathic Epiretinal Membrane and Vitreomacular Traction Syndrome

Purpose: To evaluate visual function before and after vitrectomy for idiopathic epiretinal membrane and vitreomacular traction syndrome.Methods: Microperimetry with scanning laser ophthalmoscope (SLO) was performed in 4 eyes with idiopathic epiretinal membrane (IERM) and 2 eyes with vitreomacular traction syndrome (VMTS), before and at least 3 months after vitrectomy.Results: Five eyes had preoperative scotoma, which disappeared postoperatively. In 1 eye, absolute and relative scotomas developed postoperatively over the areas where the retinal surface was vigorously scratched to peel off an overlying membrane, and in another eye new scatomas appeared over a newly formed epiretinal membrane 8 months after vitrectomy.Conclusions: To our knowledge, the present report is the first to describe preoperative absolute scotoma in IERM, VMTS and also iatrogenic absolute scotoma due to retinal scratching. SLO microperimetry is useful for evaluation of visual function before and after vitrectomy for epiretinal membrane and vitreomacular traction syndrome.     

Modelling the normal retinal nerve fibre layer thickness as measured by Stratus optical coherence tomography

Background The variation in retinal nerve fibre layer thickness (RNFLT) as measured by Stratus optical coherence tomography (OCT) in healthy subjects may be reduced when the effect on RNFLT measurements of factors other than disease is corrected for, and this may improve the diagnostic accuracy in glaucoma. With this perspective we evaluated the isolated and combined effects of factors potentially affecting the Stratus OCT RNFLT measurements in healthy subjects.Methods We included 178 healthy eyes of 178 subjects between 20 and 80 years of age. Participants underwent an extensive eye examination. Stratus OCT RNFLT was measured by three standard protocols, two with high and one with standard image resolution. Effects on RNFLT of age, gender, refractive error, axial length, lens nuclear colour and opalescence, intra-ocular pressure (IOP), and optic disc size were examined by univariate and multivariate analyses.Results Age, refractive error, axial length, and lens nuclear colour and opalescence affected RNFLT in univariate analyses, whereas gender, IOP, and optic disc size had no significant effect. In multivariate analyses only age in combination with refractive error, or with axial length, was significant and explained 14.7–17.6% (R ²) of the total variation of RNFLT, approximately 50% more than age alone. RNFLT decreased by 2.6–2.9 μm per increasing decade of age and increased by 1.5–1.8 μm per more positive diopter of spherical equivalent using full-circle measurements of the three standard protocols. These effects varied between measurement sectors.Conclusions RNFLT as measured by Stratus OCT standard protocols was significantly affected by age and refractive status. The effect on global RNFLT of a difference in refractive error of 10 diopters corresponded to the effect of a difference in age of 60 years. Theoretically, the effect of refractive status may be explained by artefacts of RNFLT measurement circle placement. The results suggest that the diagnostic accuracy of Stratus OCT may be improved by considering refractive status in addition to age when RNFLT is measured. For this purpose spherical equivalent seems as effective as axial length.     

How Spatial Orientation of Japanese Text Affects Fixation Points in Patients with Bilateral Macular Atrophy

Purpose

To ascertain the retinal area used by patients with bilateral macular atrophy when reading Japanese text of different character sizes written horizontally or vertically. In addition, to determine fixation points as part of the first of a series of studies designed ultimately to enhance the quality of life of these patients through the improvement of reading acuity.

Methods

Seventeen patients (34 eyes) with bilateral macular atrophy were tested to determine the retinal area employed for reading (R fixation point). Sentences were arranged either horizontally or vertically and projected onto the retina using a scanning laser ophthalmoscope. We also determined the fixation point using microperimetry (M fixation point). The positional relationships between these two fixation points and the scotoma were examined.

Results

The R and M fixation points were the same in 20 of the 34 eyes. Multiple R fixation points were found in 11 eyes. The R fixation point was frequently positioned above the lesion when reading horizontally (nine eyes), while it was often positioned in the area nasal to (eight eyes) or temporal to (six eyes) the lesion when reading vertically.

Conclusions

Fixation points changed frequently in these patients with bilateral macular atrophy depending on the spatial orientation of the text. These data should be used in the future to help patients learn how to use the preferred retinal locus to improve their reading skills and enhance their quality of life. Jpn J Ophthalmol 2005;49:462–468?© Japanese Ophthalmological Society 2005     

Effect of Aging on Retinal Nerve Fiber Layer Thickness in Normal Asian Indian Eyes: A Longitudinal Study

Purpose: To determine longitudinal retinal nerve fiber layer (RNFL) thickness measurement change with aging, after a period of 3 years using spectral optical coherence tomography/scanning laser ophthalmoscope (OCT/SLO).

Methods: A total of 50 eyes of 25 normal subjects underwent RNFL thickness measurement in 2008 and again in 2011 by a single operator, using spectral OCT/SLO. Measurements were compared at baseline and at follow-up. Linear mixed model analysis was used to measure the effect of age on RNFL thickness measurements over the 3 years.

Results: Mean RNFL thickness was 107.92 ± 11.1 µm in 2008 and 106.56 ± 10.8 µm in 2011. For every year increase in age, mean RNFL thickness showed a statistically significant decrease by ?0.54 µm (95% confidence interval, ?0.76 to ?0.31; p < 0.0001). There was a statistically significant loss of peripapillary RNFL thickness in most RNFL regions, except for the temporal quadrant (p = 0.37) and corresponding 7, 8, 9, and 10 o’clock hour sectors (p = 0.72, 0.75, 0.17, 0.14, respectively).

Conclusion: RNFL thickness as measured by spectral OCT/SLO decreased significantly with advancing age over a period of 3 years, and was not uniform across the four quadrants. This age-related variation should be taken into account in RNFL thickness measurements when evaluating patients for diagnosis and follow-up of glaucoma.     

Comparison of optical coherence tomography and fundus photography for measuring the optic disc size

PURPOSE: To assess the agreement and repeatability of optic nerve head (ONH) size measurements by optical coherence tomography (OCT) as compared to conventional planimetry of fundus photographs in normal eyes. METHODS: For comparison with planimetry the absolute size of the ONH of 25 eyes from 25 normal subjects were measured by both OCT and digital fundus photography (Zeiss FF camera 450). Repeatability of automated Stratus OCT measurements were investigated by repeatedly measuring the optic disc in five normal subjects. RESULTS: Mean disc size was 1763 +/- 186 vertically and 1632 +/- 160 microm horizontally on planimetry. On OCT, values of 1772 +/- 317 microm vertically (p = 0.82) and a significantly smaller horizontal diameter of 1492 +/- 302 microm (p = 0.04) were obtained. The 95% limits of agreement were (-546 microm; +527 microm) for vertical and (-502 microm; +782 microm) for horizontal planimetric compared to OCT measurements. In some cases large discrepancies existed. Repeatability of automatic measurements of the optic disc by OCT was moderately good with intra-class correlation coefficients (ICC) of 0.78 horizontally and 0.83 vertically. The coefficient of repeatability indicating instrument precision was 80 microm for horizontal and 168 microm for vertical measurements. CONCLUSIONS: OCT can be used to determine optic disc margins in moderate agreement with planimetry in normal subjects. However, in some cases significant disagreement with photographic assessment may occur making manual inspection advisable. Automatic disc detection by OCT is moderately repeatable.     

Assessment of visual function in choroidal neovascularization with scanning laser microperimetry and simultaneous indocyanine green angiography

Background: Clinical management and treatment of diseases with choroidal neovascularization (CNV) are mainly based on visual acuity, which may give an incomplete picture of the associated visual dysfunctions. With the advent of new experimental treatment modalities such as alfa-interferon, radiation, or surgical excision of CNV, it is increasingly important to develop better methods for characterizing the associated visual function. Microperimetry with the scanning laser ophthalmoscope (SLO) allows precise point-to-point correlation between visual function and the macular pathology. However, precise delineation of CNV is a prerequisite for accurate correlation of the functional results with the CNV. Methods: A total of 40 eyes with CNV secondary to age-related macular degeneration were evaluated with static manual microperimetry using the SLO to quantitate relative and absolute scotomata within the CNV. For precise delineation of the CNV, indocyanine green (ICG) angiography was simultaneously performed, allowing stimulus presentation at any desired retinal location under visual feedback of the angiogram. Results: A relative scotoma was detected in 19 and an absolute scotoma in 21 out of 40 eyes. The depth of the scotomata was correlated with the duration of symptoms (P<0.01). Eyes with well-defined CNV had significantly deeper scotomas than eyes with occult CNV (P<0.005). Conclusion: Microperimetry using the SLO and simultaneous ICG angiography demonstrated relative and absolute scotoma within the CNV. The depth of the scotoma may guide the ophthalmologist in selecting the adequate treatment.Presented in part at Macula: New Frontier, An International Symposium, Kansas City, Missouri, 1994