Visual function following photodynamic therapy for central serous chorioretinopathy: a comparison of automated macular microperimetry versus best-corrected visual acuity

Artificial intelligence in retinal screening using OCT images: A review of the last decade (2013-2023)

BACKGROUND AND OBJECTIVES

Optical coherence tomography (OCT) has ushered in a transformative era in the domain of ophthalmology, offering non-invasive imaging with high resolution for ocular disease detection. OCT, which is frequently used in diagnosing fundamental ocular pathologies, such as glaucoma and age-related macular degeneration (AMD), plays an important role in the widespread adoption of this technology. Apart from glaucoma and AMD, we will also investigate pertinent pathologies, such as epiretinal membrane (ERM), macular hole (MH), macular dystrophy (MD), vitreomacular traction (VMT), diabetic maculopathy (DMP), cystoid macular edema (CME), central serous chorioretinopathy (CSC), diabetic macular edema (DME), diabetic retinopathy (DR), drusen, glaucomatous optic neuropathy (GON), neovascular AMD (nAMD), myopia macular degeneration (MMD) and choroidal neovascularization (CNV) diseases. This comprehensive review examines the role that OCT-derived images play in detecting, characterizing, and monitoring eye diseases.

METHOD

The 2020 PRISMA guideline was used to structure a systematic review of research on various eye conditions using machine learning (ML) or deep learning (DL) techniques. A thorough search across IEEE, PubMed, Web of Science, and Scopus databases yielded 1787 publications, of which 1136 remained after removing duplicates. Subsequent exclusion of conference papers, review papers, and non-open-access articles reduced the selection to 511 articles. Further scrutiny led to the exclusion of 435 more articles due to lower-quality indexing or irrelevance, resulting in 76 journal articles for the review.

RESULTS

During our investigation, we found that a major challenge for ML-based decision support is the abundance of features and the determination of their significance. In contrast, DL-based decision support is characterized by a plug-and-play nature rather than relying on a trial-and-error approach. Furthermore, we observed that pre-trained networks are practical and especially useful when working on complex images such as OCT. Consequently, pre-trained deep networks were frequently utilized for classification tasks. Currently, medical decision support aims to reduce the workload of ophthalmologists and retina specialists during routine tasks. In the future, it might be possible to create continuous learning systems that can predict ocular pathologies by identifying subtle changes in OCT images.

Crossover to Half-Dose Photodynamic Therapy or Eplerenone in Chronic Central Serous Chorioretinopathy Patients

PURPOSE

To compare the efficacy and safety of crossover treatment to half-dose photodynamic therapy (PDT) and eplerenone treatment after the failure of primary treatment in patients with chronic central serous chorioretinopathy (cCSC).

DESIGN

Multicenter crossover clinical trial.

SUBJECTS

At 3 months after the baseline visit of the SPECTRA (Half-Dose Photodynamic Therapy Versus Eplerenone: Treatment Trial for Chronic Central Serous Chorioretinopathy) randomized controlled trial, either half-dose PDT or eplerenone treatment was evaluated for each patient, and patients who still demonstrated subretinal fluid (SRF) were included in the current study, the SPECS (Central Serous Chorioretinopathy Treated with Half-Dose PDT or Eplerenone Crossover Study) trial.

METHODS

At the baseline visits for the current SPECS trial, crossover treatment was performed for patients who still demonstrated SRF. These patients received either half-dose PDT or oral eplerenone for 12 weeks. Both anatomic and functional parameters were evaluated 3 months after crossover treatment.

MAIN OUTCOME MEASURES

Complete resolution of SRF on OCT.

RESULTS

Forty-nine patients were included in the SPECS trial (38 received primary eplerenone treatment; 11 received half-dose PDT). At 3 months after crossover treatment, 32 of 37 (86.5%) in the crossover to half-dose PDT group and 2 of 9 (22.2%) in the crossover to eplerenone group had complete SRF resolution (P = 0.030). The mean foveal sensitivity increased significantly more in the crossover to half-dose PDT group (mean, +3.08 dB) compared with the crossover to eplerenone group (mean, -0.27 dB; P = 0.009).

CONCLUSIONS

Patients with cCSC with the persistence of SRF after primary eplerenone treatment can benefit from half-dose PDT, which can induce a relatively fast and complete SRF resolution, along with an improvement in foveal sensitivity.

Predicting retinal sensitivity using optical coherence tomography parameters in central serous chorioretinopathy

PURPOSE

To predict changes in retinal sensitivity using optical coherence tomography (OCT) in eyes with central serous chorioretinopathy (CSC).

METHODS

Twenty-three eyes in 23 patients with CSC were enrolled. Retinal sensitivity was measured twice using microperimetry in all the examined eyes. Spectral domain OCT measurements were simultaneously conducted. The relationship between retinal sensitivity and the thicknesses of (i) the retinal nerve fiber layer plus the ganglion cell layer (RNFL + GCL), (ii) the inner nuclear layer (INL), (iii) the outer nuclear layer (ONL), and (iv) the serous retinal detachment height (SRDH) were investigated in a point-wise manner. The associations between the change in retinal sensitivity and the OCT parameters at baseline were also investigated.

RESULTS

The mean age of the participants was 49.8 ± 10.7 years. The mean SRDH was significantly lower (p < 0.001), and the mean retinal sensitivity (p < 0.001) was significantly higher at the second examination, compared with the first; however, the logMAR visual acuity (VA) did not differ significantly between the two examinations (p = 0.063). The logMAR VA was associated with retinal sensitivity at both the first and second examinations (p < 0.001). The retinal sensitivity at the second examination was significantly correlated with the retinal sensitivity, RNFL + GCL, INL, ONL, and SRDH at the first examination and with the improvement in SRDH.

CONCLUSIONS

Retinal sensitivity was associated with the retinal structure in eyes with CSC; these parameters could be useful for predicting the change in visual function prior to treatment.

Long-Term Effects of Half-Time Photodynamic Therapy on Retinal Sensitivity in Eyes with Chronic Central Serous Chorioretinopathy

The purpose of this study was to evaluate the long-term effects of half-time photodynamic therapy (PDT) on the retinal sensitivity in eyes with chronic central serous chorioretinopathy (CSC). Twenty-two eyes of 22 patients with chronic CSC were studied. PDT was applied with full-dose verteporfin and half-time laser duration. The best-corrected visual acuity (BCVA) and retinal sensitivity in the central 2 and 10 degrees were evaluated at the baseline, and at 12 and 24 months after the half-time PDT. The retinal sensitivity was determined by Macular Integrity Assessment microperimetry (MAIA, Centervue, Padova, Italy). The results showed that the mean retinal sensitivities in the central 2 and 10 degrees were significantly improved at 12 months (25.6 ± 2.79 dB, median; 26.11 dB, 25.6 ± 2.25 dB, median; 25.65 dB, respectively; P < 0.001) and at 24 months (26.3 ± 2.62 dB, median; 27.38 dB, 26.6 ± 2.21 dB, median; 27.45 dB, respectively; P < 0.001) after the treatment compared to that at the baseline (19.2 ± 3.93 dB, median; 19.34 dB, 20.9 ± 2.92 dB, median; 20.9 dB, respectively). The BCVA was also significantly improved from 0.18 ± 0.19 median; 0.15 logarithm of the minimum angle of resolution (logMAR) units at the baseline to 0.07 ± 0.15 median; 0 logMAR units at 12 months (P < 0.001) and to 0.049 ± 0.16 median; -0.039 logMAR units at 24 months (P < 0.001). We conclude that half-time PDT results in a significant improvement of the mean central retinal sensitivity for at least 24 months in eyes with chronic CSC. Thus, half-time PDT is beneficial in resolving chronic CSC for a relatively long period.

Crossover to Photodynamic Therapy or Micropulse Laser After Failure of Primary Treatment of Chronic Central Serous Chorioretinopathy: The REPLACE Trial

PURPOSE

To assess whether chronic central serous chorioretinopathy (cCSC) patients without a complete resolution of subretinal fluid (SRF) after either half-dose photodynamic therapy (PDT) or high-density subthreshold micropulse laser (HSML) treatment may benefit from crossover treatment.

DESIGN

Multicenter prospective interventional case series.

METHODS

cCSC patients with persistent SRF at the final visit of the PLACE trial were included. Patients received crossover treatment with either half-dose PDT or HSML.

RESULTS

Thirty-two patients received PDT and 10 patients received HSML. At the first evaluation visit (6-8 weeks after treatment), 81% of patients in the PDT group had complete resolution of SRF, while none of the HSML-treated patients had complete resolution of SRF. At final visit (1 year after baseline), 78% (P = .030) and 67% (P = .109) of the patients, respectively, had a complete resolution of SRF. The mean retinal sensitivity in the PDT group increased from 21.7 dB (standard error [SE]: 0.9) to 23.4 dB (SE: 0.8) at evaluation visit 1 (P = .003), to 24.7dB (SE: 0.8) at final visit (P < .001), while there were no significant changes in the HSML group (23.7 dB [SE: 1.6] at baseline, 23.8 dB [SE: 1.4] at evaluation 1, and 23.3 dB [SE: 1.4] at final visit). The mean visual acuity and mean visual quality-of-life questionnaire score did not change significantly in both groups.

CONCLUSIONS

Crossover to half-dose PDT after previous unsuccessful HSML treatment for cCSC may lead to improved anatomic and functional endpoints, while crossover to HSML after half-dose PDT does not seem to significantly affect these endpoints.

Macular Integrity Assessment and Fixation Analysis in Chronic Central Serous Chorioretinopathy

Purpose

To investigate retinal sensitivity characteristics associated with morphologic changes in the eyes exhibiting chronic central serous chorioretinopathy (CSC), using macular integrity assessment (MAIA) microperimetry.

Methods

A retrospective, cross-sectional, observational study was constructed. The eyes of patients classified as chronic CSC, according to the onset of subjective symptoms with serous retinal detachment, as confirmed by optical coherence tomography examination, were included in the study. Retinal sensitivity and fixation were analyzed by performing microperimetry examinations using the MAIA instrument.

Results

We reviewed microperimetry examinations of 15 eyes of 15 patients (age: 28-51 years) with chronic CSC and mean best-corrected visual acuity of -0.2 logMAR units. The mean retinal integrity in the chronic CSC group was 49.0 ± 27.6, which was significantly different from the control eyes. The mean average threshold in the eyes with chronic CSC was 24.7 ± 5.8 dB, which also was significantly different from the control eyes. Fixation stability was significantly different between the CSC and control eyes for the P1 parameter (90.1 ± 13.7 versus 99.3 ± 1.5), and for the P2 parameter (97.4 ± 4.0 versus 100.0 ± 0.0).

Conclusion

New microperimetry technology may provide valuable information regarding the visual status of chronic CSC cases. Our findings suggest that retinal sensitivity and fixation stability in chronic CSC eyes may serve as useful indicators for assessing the effectiveness of clinical treatments.

The association between visual function and retinal structure in chronic central serous chorioretinopathy

The purpose of the current study was to investigate the association between visual function and retinal structure in central serous chorioretinopathy (CSC). In 22 eyes of 22 chronic CSC patients with serous retinal detachment at the macula, retinal sensitivity was measured using MP3 microperimetry (NIDEK, Japan) and mean sensitivity within two degrees (MS₂), four degrees (MS₄) and six degrees (MS₆), as well as foveal sensitivity (MS₀), were calculated. Retinal structure was measured using optical coherence tomography (OCT, Spectralis, Heidelberg). The relationship between visual function (LogMAR best-corrected visual acuity [LogMAR VA] and MS₀, MS₂, MS₄, MS₆) and serous retinal detachment height at the fovea (SRDH), central retinal thickness (CRT), macular volume (MV) and central choroidal thickness (CCT) was investigated. There were significant negative correlations between LogMAR VA and MS₀ (p = 0.016), MS₂ (p = 0.049). No significant relationship was observed between LogMAR VA and SRDH (p = 0.97) although there was a significant negative correlation between SRDH and MS₂ (p = 0.028), MS₄ (p = 0.049), MS₆ (p = 0.023). In conclusion, in CSC, serous retinal detachment was significantly correlated with retinal sensitivity measured with MP3, but not with LogMAR VA.

Early Focal Laser Photocoagulation in Acute Central Serous Chorioretinopathy: A Prospective, Randomized Study

BACKGROUND AND OBJECTIVE

To evaluate the role of early focal laser photocoagulation in acute central serous chorioretinopathy (CSC).

PATIENTS AND METHODS

A total of 58 eyes with acute naïve CSC (less than 2 months' duration) with focal leak on fundus fluorescein angiography (FFA) were randomized into either a laser or a sham laser group. Eyes with chronic CSC and subfoveal leak were excluded. Visual acuity assessment, microperimetry, optical coherence tomography, and FFA were done at baseline, 1 month (minus FFA), 3 months, and 6 months after treatment.

RESULTS

There was a significant improvement in best-corrected visual acuity, low-contrast visual acuity, retinal sensitivity, and central macular thickness at all visits in both groups (P < .001); however, there was no significant difference between the groups regarding time of resolution. Four eyes in the sham laser group needed rescue laser compared with one eye in early laser group (P = .16).

CONCLUSION

Early laser photocoagulation is not superior to sham laser for acute CSC; therefore, observation appears to the safest and most effective strategy. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:564-571.].

Changes in macular sensitivity after half-dose photodynamic therapy for chronic central serous chorioretinopathy

BACKGROUND

To evaluate the macular sensitivity changes after half-dose photodynamic therapy (PDT) for chronic central serous chorioretinopathy (CSCR).

METHODS

Eighteen patients (26 eyes) with chronic CSCR were recruited in the same hospital between April 2011 and December 2012. All patients were treated with one session of half-dose PDT after complete ophthalmic examination. Macular sensitivity examination was performed at baseline and 1, 3 and 6 months post-treatment. Mean sensitivity (MS) of the central 10 degrees (10°) and 4 degrees (4°), mean deviation (MD) and pattern standard deviation (PSD) on automated static perimetry (Humphrey Field Analyzer II-750) were used for analysis.

RESULTS

There was significant improvement of the 10°MS from baseline (29.76 ± 1.51 dB) to 1 month (31.74 ± 1.56 dB), 3 months (31.51 ± 1.38 dB) and 6 months (31.19 ± 1.61 dB) after treatment (P < 0.001). The 4°MS was also significantly improved with half-dose PDT from baseline (28.96 ± 1.78 dB) to 1 month (32.41 ± 1.66 dB), 3 months (32.46 ± 1.50 dB) and 6 months (31.90 ± 1.84 dB) post-treatment (P < 0.001). MD was improved from baseline (-3.39 ± 0.89 dB) to 1 month (-1.96 ± 0.29 dB), 3 months (-1.94 ± 0.29 dB) and 6 months (-2.45 ± 0.13) post-treatment (P = 0.004). PSD also improved from 1.97 ± 0.24 dB at baseline to 1.47 ± 0.27 dB, 1.34 ± 0.24 dB, and 1.53 ± 0.24 dB (P = 0.001) at 1, 3 and 6 months after treatment, respectively.

CONCLUSION

Macular sensitivity in CSCR can be improved by half-dose PDT, along with improvement of visual acuity and retinal thickness. The treatment outcome at 1 month may be a predictor of the final treatment response.

Microsecond yellow laser for subfoveal leaks in central serous chorioretinopathy

Purpose

To evaluate the role of navigated yellow microsecond laser in treating subfoveal leaks in nonresolving central serous chorioretinopathy (CSC).

Methods

This prospective study included ten eyes of ten consecutive patients with nonresolving CSC with subfoveal leaks. All eyes were treated with 577 nm navigated yellow microsecond laser (5% duty cycle). Key inclusion criteria include a vision loss for a duration of minimum 3 months duration due to focal subfoveal leak on fluorescein angiography. Key exclusion criteria include prior treatment for CSC and any signs of chronic CSC. Comprehensive examination, in addition to low-contrast visual acuity assessment, microperimetry, autofluorescence, spectral domain optical coherence tomography, and fundus fluorescein angiography, was done at baseline, 1, 3, and 6 months after treatment. Rescue laser was performed as per predefined criteria at 3 months.

Results

The average best-corrected visual acuity improved from 73.3±16.1 letters to 75.8±14.0 (P=0.69) at 3 months and 76.9±13.0 (P=0.59) at 6 months, but was not statistically significant. Low-contrast visual acuity assessment (logMAR) improved from 0.41±0.32 to 0.35±0.42 (P=0.50) at 3 months and 0.28±0.33 (P=0.18) at 6 months. Average retinal sensitivity significantly improved from baseline 18.93±7.19 dB to 22.49±6.67 dB (P=0.01) at 3 months and 21.46±8.47 dB (P=0.04) at 6 months. Rescue laser was required only in one eye at 3 months; however, laser was required in three eyes at 6 months.

Conclusion

Microsecond laser is a safe and effective modality for treating cases of nonresolving CSC with subfoveal leaks.

Clinical application of optical coherence tomography in combination with functional diagnostics: advantages and limitations for diagnosis and assessment of therapy outcome in central serous chorioretinopathy

Purpose

While identifying functional and structural parameters of the retina in central serous chorioretinopathy (CSCR) patients, this study investigated how an optical coherence tomography (OCT)-based diagnosis can be significantly supplemented with functional diagnostic tools and to what degree the determination of disease severity and therapy outcome can benefit from diagnostics complementary to OCT.

Methods

CSCR patients were evaluated prospectively with microperimetry (MP) and spectral domain optical coherence tomography (SD-OCT) to determine retinal sensitivity function and retinal thickness as outcome measures along with measures of visual acuity (VA). Patients received clinical care that involved focal laser photocoagulation or pharmacotherapy targeting inflammation and neovascularization.

Results

Correlation of clinical parameters with a focus on functional parameters, VA, and mean retinal sensitivity, as well as on the structural parameter mean retinal thickness, showed that functional measures were similar in diagnostic power. A moderate correlation was found between OCT data and the standard functional assessment of VA; however, a strong correlation between OCT and MP data showed that diagnostic measures cannot always be used interchangeably, but that complementary use is of higher clinical value.

Conclusion

The study indicates that integrating SD-OCT with MP provides a more complete diagnosis with high clinical relevance for complex, difficult to quantify diseases such as CSCR.

What is new in central serous chorioretinopathy?

Central serous chorioretinopathy (CSCR) is considered a benign, self-limiting disease. However, as many as third of the patients have recurrent episodes or chronic disease that may cause significant functional impairment. New diagnostic tools and new treatment modalities are emerging in order to improve the functional outcomes of these patients. Spectral domain optical coherence tomography (SD-OCT) has the ability to image individual layers of the retina and choroid. SD-OCT images in CSCR patients have demonstrated increased subfoveal thickness measurements, high reflective deposits in areas of subretinal precipitates and changes in the Retinal pigment epithelium layers of the asymptomatic eyes of patients with supposedly unilateral CSCR. A positive correlation was found between the level of distribution to the layer of inner segment/outer segment junction of the photoreceptors and the visual impairment. Fundus autoflouresence images show a wide variety during different stages of the disease in CSCR patients. Minimal abnormalities during the early stages are followed by hyperautofluoresence in the detached area in later stages, often in a manner of inferior gravitation and at the borders of the detachments. The chronic phase is characterized by varying degrees of atrophy and areas of decreased autofluorescence surrounding areas of chronic leaks. These changes help differentiate an active disease from an inactive state. Multifocal electroretinography (mfERG) has the ability to demonstrate a persistent depression despite the resolution of subretinal detachments. It is therefore being investigated as a follow up tool for patients with chronic CSCR. An excellent correlation was found between changes in mfERG and visual function. Macular microperimetry, measuring retinal sensitivity within the central visual field, is intended to compensate for the underestimation of visual impairment in patients with macular diseases. Reduced retinal sensitivity was found in areas of previous subretinal fluids in CSCR patients. The device can also serve as a follow up tool in these patients. Regarding treatment in CSCR patients, focal argon laser photocoagulation treatment may be applied to small extrafoveal leaks. However, the main purpose of this treatment is to shorten disease duration, with no advantage over observation regarding final visual outcome, rate of progression to chronic CSCR or number of recurrences. Photodynamic therapy (PDT) with verteporfin has been shown to completely resolve serous detachment in 60%-80% of patients and to have a partial affect in the remaining patients. Reduced-fluence treatment is replacing full-fluence therapy in order to minimize side effects with no accompanying reduced effectiveness. Visual acuity is also improved following reduced-fluence PDT compared to placebo. It has also been found that patients with intense hyperfluorescence are more likely to show resolution of accumulating fluid compared to patients with mild or no leakage observed on indocyanine-green angiography prior to treatment. Regarding newer treatment modalities, intravitreal injections of anti-vascular endothelial growth factor agents have a limited effect in patients with CSCR. Recent reports have not demonstrated an advantage for this treatment in regards to anatomic and functional outcome. Micropulse diode laser was not proven to be safer or more effective than argon laser or PDT. Corticosteroid antagonists, not tested in controlled trials, may have a beneficial effect in patients with CSCR. Aspirin may also play a role in treating these patients, with rapid recovery of visual acuity and reduced number of recurrences observed. In conclusion, imaging is evolving rapidly while the clinical implications of these new imaging modalities are less clear. Large randomized trials investigating different treatment modalities are still lacking.

Retinal sensitivity assessed by microperimetry and corresponding retinal structure and thickness in resolved central serous chorioretinopathy

PURPOSE

To investigate the relationship between retinal sensitivity (RS) assessed by microperimetry (MP) and retinal structural changes in patients with resolved central serous chorioretinopathy (CSC).

METHODS

Spectral domain optical coherence tomography (OCT) examination and MP tests were performed in patients with resolved CSC. Point-to-point correlation was performed between RS and corresponding retinal structural changes using Pearson's correlation analysis. In addition, in a 1-mm zone in the central fovea, a correlation was calculated between the mean RS and the mean central retinal thickness (CRT).

RESULTS

Eighty-four eyes were analyzed. The total number of MP test points was 1092 (84 eyes × 13 points). The mean RS and retinal point thickness (RPT) of all test points were 13.53±3.84 dB and 208.6±48.0 μm, respectively. The RS and RPT were significantly decreased in the test points with loss of the ellipsoid portion of the inner segments (EPIS) (P<0.0001). Within the 1-mm foveal center zone, there was a significant correlation between mean RS and mean CRT (r=0.432, P<0.0001) and between RS and the corresponding RPT (r=0.339, P<0.0001).

CONCLUSION

RS was dependent on the status of the EPIS in patients with resolved CSC. The correlation between mean RS and mean CRT was compatible with the point-to-point correlation between RS and the corresponding RPT.

Central serous chorioretinopathy: update on pathophysiology and treatment

Recent technological advances--new pathophysiological insights, new imaging techniques for diagnosis and management, and new treatments--have led to an improved understanding of central serous chorioretinopathy (CSC). The primary role of the choroid has become more widely accepted with widespread use of indocyanine green angiography. Optical coherence tomography (OCT), and particularly enhanced depth imaging OCT, demonstrate a thickened and engorged choroid. Adaptive optics, fundus autofluorescence, multifocal electroretinography, microperimetry, and contrast sensitivity testing reveal that patients with even a mild course suffer previously undetected anatomic and functional loss. Although focal laser and photodynamic therapy are the current standard of care for persistent subretinal fluid in CSC, they are not appropriate in all cases, and the optimal timing of intervention remains unclear.

Comparison between MP-1 and Humphrey visual field defects in glaucoma and retinitis pigmentosa

PURPOSE

To compare MP-1 microperimeter and Humphrey Field Analyzer (HFA) defects, in patients with retinitis pigmentosa (RP), a disease primarily affecting the photoreceptors, and in patients with glaucoma, a disease primarily affecting postreceptoral ganglion cells, and to analyze the similarities and differences between the results.

METHODS

Eleven patients (11 eyes) with RP and 10 patients (10 eyes) with primary open-angle glaucoma (OAG) underwent MP-1 and HFA visual field testing (10-2 pattern). All tested eyes had defects encroaching within 10° of fixation. MP-1 total deviation (TD) probability defects, derived from a previously collected normative database of 50 subjects, were compared to HFA TD defects and to the local defect map of the MP-1. Test duration was compared between instruments.

RESULTS

In RP patients, MP-1 scotomata were deeper and wider than HFA defects; however in OAG, the opposite was observed. Examination duration in both patient groups was 12 to 14 min for the MP-1 and 6 min for the HFA. The MP-1 local defect map tended to overestimate defects compared to the MP-1 TD analysis.

CONCLUSIONS

The differences in results between the MP-1 and HFA for the two groups of patients with RP and OAG can be attributed to the different adaptation levels and to the dynamic range of test lights available for the two instruments. The clinician should also be aware of the possible consequences of the differences in the method of derivation of normative data for the two instruments, as this may affect the interpretation of visual field results.

Relationship between retinal layer thickness and the visual field in early age-related macular degeneration

PURPOSE

To quantify and compare the structural and functional changes in subjects with early age-related macular degeneration (AMD), using spectral-domain optical coherence tomography (SD-OCT) and microperimetry.

METHODS

Twenty-one eyes of 21 subjects with early AMD were examined. MP-1 10-2 visual fields (VFs) and SD-OCT line and detail volume scans were acquired. The thicknesses of the outer segment (OS; distance between inner segment ellipsoid band and upper retinal pigment epithelium [RPE] border) and RPE layers and elevation of the RPE from Bruch's membrane were measured using a computer-aided manual segmentation technique. Thickness values were compared with those for 15 controls, and values at locations with VF total deviation defects were compared with values at nondefect locations at equivalent eccentricities.

RESULTS

Sixteen of 21 eyes with AMD had VF defects. Compared with controls, line scans showed significant thinning of the OS layer (P = 0.006) and thickening and elevation of the RPE (P = 0.037, P = 0.002). The OS layer was significantly thinner in locations with VF defects compared with locations without defects (P = 0.003). There was a negligible difference between the retinal layer thickness values of the 5 eyes without VF defects and the values of normal controls.

CONCLUSIONS

In early AMD, when VF defects were present, there was significant thinning of the OS layer and thickening and elevation of the RPE. OS layer thinning was significantly associated with decreased visual sensitivity, consistent with known photoreceptor loss in early AMD. For AMD subjects without VF defects, thickness values were normal. The results highlight the clinical utility of both SD-OCT retinal layer quantification and VF testing in early AMD.