Assessment of ganglion cell complex thickness and its correlation with retinal sensitivity using microperimetry 6 months after epiretinal membrane surgery.

PURPOSE: To verify the correlation between the full-macular and the ganglion cell complex (GCC) thickness measurements and retinal sensitivity (RS) assessed by microperimetry (MP) 6 months after surgical peeling for idiopathic epiretinal membrane (ERM). METHODS: Forty-three were submitted to pars-plana posterior vitrectomy (PPV) with concomitant peeling of internal limiting membrane (ILM) for idiopathic ERM treatment. Best-corrected visual acuity (BCVA) and 3D volumetric high-definition optical coherence tomography (OCT) imaging were preoperatively acquired. Six months after the surgery, BCVA, OCT imaging, and RS measured by MP were assessed. For the OCT parameters, we analyzed both the full-macular and the ganglion cell layer complex (GCC) thicknesses. The MP parameters tested were 44 points covering 20 central degrees (6 mm), with direct correspondence with the nine sectors of the OCT-ETDRS map. This approach enables the direct topographic correlation between the structure and functional measurements. The OCT and MP exam measurements were also performed in 43 eyes of age-matched healthy controls. Correlations between BCVA, RS, and OCT parameters were examined. RESULTS:  All patients exhibited a substantial improvement in visual acuity following surgery. The RS parameters were significantly lower in patients compared to the controls. The full-macular thickness measurements were thicker than controls preoperatively and significantly reduced postoperatively; however, remaining significantly higher than controls, in the 4 inner sectors, at the fovea and for the average macular thickness. Preoperative GCC measurements were higher than those in controls. There was a significant reduction in GCC thickness in all sectors postoperatively, especially in the outer sectors, as well as in the average macular thickness. A positive correlation was found between full-macular and GCC thickness and RS postoperatively in several sectors. CONCLUSIONS: Our results demonstrate that ERM peeling can improve visual acuity in the postoperative period. However, RS may not fully restore, remaining significantly lower when compared to the controls. Both full-macular and GCC thickness measurements were reduced 6 months after surgery. However, significant thinning of the GCC thickness was observed when compared to the normal control eyes, indicating the occurrence of some degree of ganglion cell layer atrophy. We have demonstrated significant correlations among various OCT thickness parameters, particularly for GCC measurements. We believe that GCC integrity may play an important role in visual function after ERM surgery, and that MP may help better understand the correlations between structural and functional findings following ERM surgery.

Correlation between retinal sensitivity assessed by microperimetry and structural abnormalities on optical coherence tomography after successful epiretinal membrane surgery.

BACKGROUND: To verify the correlation between retinal sensitivity (RS) assessed by the microperimetry (MP) and optical coherence tomography (OCT) parameters measured in eyes submitted to pars-plana vitrectomy (PPV) for idiopathic epiretinal membrane (ERM) treatment. METHODS: 43 patients underwent PPV. Best-corrected visual acuity (BCVA) and OCT imaging were acquired preoperatively and 6 months after surgery. The RS values were recorded 6 months after the surgery. Total macular thickness (TMT) measurements and OCT-evaluated structural findings were also analyzed. The MP examination tested 44 points, with direct topographic correspondence with the OCT-ETDRS map. Correlations between BCVA, RS, and OCT parameters were assessed. RESULTS: TMT measurements in patients were significantly thicker preoperatively and reduced after surgery. All patients demonstrated BCVA improvements after surgery. The RS parameters after surgery were significantly lower in patients. For OCT structural analyses, patients with lower RS at the fovea correlated with the preexisting disorganization of retinal inner layers (DRIL). In addition, lower RS values were associated with DRIL, outer retinal changes (ORC), and intraretinal microcysts after surgery. CONCLUSIONS: The RS values after surgery were significantly lower when compared to controls. The DRIL presence before and after surgery, and microcysts and ORC after surgery were related to worse visual outcomes.

Biofeedback Training after Successful Inverted Internal Limiting Membrane (ILM)-Flap Technique for High Myopic Macular Hole.

BACKGROUND: Microperimetric biofeedback training improved visual acuity and fixation stability in patients who previously underwent macular surgery. We aimed to compare the functional results of biofeedback training with the standard of care in patients who underwent successful inverted Internal Limiting Membrane (ILM)-flap technique for high myopic macular holes (hMMH). METHODS: This was a retrospective, comparative, cohort study. Patients with hMMH after surgical hole closure underwent microperimetric biofeedback using structured light stimulus plus acoustic tone (n = 12; Biofeedback) or standard of care with scheduled visits (n = 11; Control). Best-corrected visual acuity, retinal sensitivity at central 12° (RS) and 4° (CRS) with a mean deviation at central 12° (MD), and fixation stability as bivariate contour ellipse area (BCEA 68%, 95%, and 99%) were assessed at baseline and month 1, 3, 6, and 12. The Mann-Whitney test was used to test the difference between the groups. RESULTS: Baseline functional parameters were not significantly different among the groups. BCVA significantly improved in each group (Biofeedback, p = 0.002; Control, p ≤ 0.02) at all follow-up visits. CRS significantly improved at 6 (p = 0.03) and 12 (p = 0.01) months in the Biofeedback group and at month 12 (p = 0.01) in the Control group. RS (p = 0.001) and MD (p = 0.005) improved at the last follow-up only in the trained group. After training, BCEA 68% and 95% significantly improved (6 and 12 months, p < 0.05). The Biofeedback group had better results in RS (p ≤ 0.02), CRS (p ≤ 0.02), and BCEA 68%, 95%, and 99% (p ≤ 0.01) compared to the Control at all follow-ups. BCVA and MD were better in the Biofeedback group at month 3 (p = 0.01), and month 3 (p = 0.01) and 12 (p = 0.003), respectively. CONCLUSIONS: Microperimetric biofeedback can increase retinal sensitivity and stabilize fixation better than the standard care over months after a successful inverted ILM-flap for hMMH.

Role of eccentric viewing training with microperimeter for low vision rehabilitation in multifocal choroiditis: Case report.

A 21-year-old student with healed multifocal choroiditis involving the macula presented with difficulty in seeing distance and reading her college books. Based on microperimetr'y, the location of her preferred retinal locus and the position of new trained retinal locus (TRL) were identified. With multiple sessions of biofeedback training, her mean retinal sensitivity improved from 4.8 to 8.8 dl, distance vision from 3/60 to 6/36, and near vision from N32 to N8 in the right eye. At 6-month follow-up, her TRL position and visual acuity were found to be stable. This case report highlights that eccentric viewing training using microperimeter can significantly improve the efficiency of functional vision in patients with choroiditis.

Microstructural and microperimetric comparison of internal limiting membrane peeling and insertion in large idiopathic macular hole.

BACKGROUND: The internal limiting membrane (ILM) insertion technique was widely used to treat large macular hole (MH) for the high closure rate. However, the prognosis of closed MH after ILM insertion compared to ILM peeling remains controversial. This study aimed to compare foveal microstructure and microperimeter in large idiopathic MH surgically closed by ILM peeling and ILM insertion. METHODS: This retrospective, non-randomized, comparative study included patients with idiopathic MH (minimum diameter ≥ 650 µm) who underwent primary pars plana vitrectomy (PPV) with ILM peeling or ILM insertion. The initial closure rate was recorded. Patients with initially closed MHs were divided into two groups according to the surgery methods. The best-corrected visual acuity (BCVA), optical coherence tomography (OCT) and microperimeter-3 (MP-3) outcomes of two groups were compared at baseline, 1 and 4 months postoperatively. RESULTS: For idiopathic MH (minimum diameter ≥ 650 µm), ILM insertion had a significantly higher initial closure rate than ILM peeling (71.19% vs. 97.62%, P = 0.001). Among 39 patients with initially closed MHs who were on regular follow-up, twenty-one were assigned to the ILM peeling group and 18 to the ILM insertion group. Postoperative BCVA improved significantly in both groups. The final BCVA (logMAR) (0.40 vs. 0.88, P < 0.001), macular hole sensitivity (19.66 dB vs. 14.14 dB, P < 0.001), peripheral sensitivity of macular hole (24.63 dB vs. 21.95 dB, P = 0.005), and fixation stability (FS) within 2 degrees (82.42% vs. 70.57%, P = 0.031) were significantly better and external limiting membrane (ELM) defect (330.14 µm vs. 788.28 µm, P < 0.001) and ellipsoid zone (EZ) defect (746.95 µm vs. 1105.11 µm, P = 0.010) were significantly smaller in the ILM peeling group than in the ILM insertion group. CONCLUSION: For initially closed MHs (minimum diameter ≥ 650 µm), both ILM peeling and ILM insertion significantly improved the microstructure and microperimeter in the fovea. However, ILM insertion was less efficient at microstructural and functional recovery after surgery.

Ocular findings in asymptomatic patients with primary antiphospholipid syndrome.

BACKGROUND: Primary antiphospholipid syndrome (PAPS) is characterized by the presence of antiphospholipid antibodies (aPL), repetitive fetal loss, and arterial/venous thrombosis and no association with other autoimmune rheumatic disease. Ocular involvement can also occur including retinal vascular thrombosis and neuro-ophthalmological manifestations, such as optic neuropathy and amaurosis fugax. Early detection of ocular changes is crucial to minimize functional loss. PURPOSE: To perform a multimodal evaluation, including the use of Optical Coherence Angiotomography (OCTA), in patients with PAPS without ocular complaints and compare with healthy individuals. METHODS: We performed a complete structural and functional ophthalmological evaluation using OCTA and microperimetry exam in patients with PAPS, followed at a tertiary Rheumatology outpatient clinic. RESULTS: We included 104 eyes of 52 subjects [PAPS without ocular complaints (N = 26) and healthy individuals (N = 26)]. Among PAPS patients, 21 were female (80.8%) and 21 (80.8%) were Caucasians. PAPS manifestations were venous (65.4%), arterial thrombosis (34.6%), and obstetrical (34.6%) and all of them had lupus anticoagulant. Ophthalmologic findings were more frequent in PAPS compared to healthy individuals (19.2% vs. 0%, p = 0.05). The most common retinal change was paracentral acute middle maculopathy (PAMM) (3 patients, 5 eyes), followed by drusen (1 patient, 2 eyes) and pachychoroid pigment epitheliopathy (PPE) (1 patient, 1 eye). Hypertension and hyperlipidemia were present in 100% of the PAPS patients with PAMM, while only six patients (26.1%) with PAPS without PAMM presented these two risk factors together (p = 0.03). CONCLUSIONS: We provide novel evidence that approximately 20% of our asymptomatic PAPS patients without ocular symptoms have ophthalmologic findings that require early identification and careful surveillance focusing on minimizing systemic and vascular risk factors.

Efficacy of MP-3 microperimeter biofeedback fixation training for low vision rehabilitation in patients with maculopathy.

BACKGROUND: To evaluate the efficacy of MP-3 microperimeter biofeedback fixation training (MBFT) in vision rehabilitation of low-vision patients affected by macular disease with central vision loss. METHODS: Seventeen eyes (7 age-related macular degeneration, 10 myopic maculopathy) of 17 patients were included in this prospective, interventional study. The preferred retinal locus was determined by comprehensive ophthalmoscopic fundus evaluation including fundus photography, autofluorescence, optical coherence tomography, and microperimetry. The rehabilitation consisted of three 10-min sessions per eye to be performed twice per week for 20 consecutive weeks using the MP-3 microperimeter. Best corrected visual acuity (BCVA), reading speed, mean central sensitivity, the percentages of fixation points within specified regions, bivariate contour ellipse area (BCEA) and the 25-item National Eye Institute visual function questionnaire (NEI-VFQ-25) were recorded pre- and post-training. RESULTS: The final BCVA, reading speed and mean central sensitivity all showed significant improvements after rehabilitation (P <  0.0001, P = 0.0013, and P = 0.0002, respectively). The percentages of fixation points located within 2° and 4° diameter circles both significantly increased after training (P = 0.0008 and P = 0.0007, respectively). The BCEA encompassing 68.2, 95.4, 99.6% of fixation points were all significantly decreased after training (P = 0.0038, P = 0.0022, and P = 0.0021, respectively). The NEI-VFQ-25 scores were significantly increased at the end of the rehabilitation training (P <  0.0001). CONCLUSION: Rehabilitation with MP-3 MBFT is a user-friendly therapeutic option for improving visual function, fixation stability, and quality of life in advanced macular disease. TRIAL REGISTRATION: The prospective study was registered with the Chinese Clinical Trial Registry ( http://www.chictr.org.cn/ ). TRIAL REGISTRATION NUMBER: ChiCTR2000029586 . Date of registration: 05/02/2020.

MAIA microperimeter for short-duration fixation stability measurements in central vision loss: Repeatability and comparison with the Nidek MP1.

PURPOSE: This study reports the repeatability of 20 s-duration fixation stability measurements recorded with the Macular Integrity Assessment (MAIA) microperimeter in patients with central vision loss, in contrast to the Nidek MP1 microperimeter. METHODS: Fixation stability was recorded in 39 eyes of 25 patients with macular disease using MAIA and the MP1 for 20 s intervals, twice for each eye, with each instrument. Twenty eyes were identified as the better eye (BE) and 19 eyes as the worse eye (WE). Fixation stability was quantified with the 95% bivariate contour ellipse area (BCEA), logarithmically transformed. Bland-Altman plots were used to determine the 95% limits of agreement. RESULTS: For MAIA, the 95% limits of agreement were ±0.84 log deg2 for the BE and ±0.66 log deg2 for the WE. Similarly, for the MP1 these limits were ±0.48 log deg2 for the BE and ±0.72 log deg2 for the WE. Inter-device repeatability was modest, ±1.09 log deg2 for the BE and ±1.01 log deg2 for the WE, and a proportional bias was detected. Occasionally, MAIA did not register all the expected number of data points, and included far outliers in the BCEA calculation; the inter-device repeatability did not improve when these outliers were removed. CONCLUSIONS: Repeatability of 20 s-duration fixation stability examination in patients with central vision loss is specific to the instrument used. We recommend that only data from same type of microperimeter with the same fixation duration should be compared when using fixation stability as an outcome measure to monitor disease progression, effect of treatment or in clinical trials.

Role of microperimetry in evaluating disease progression in age-related macular degeneration: a scoping review.

PURPOSE: Recent research has found variable evidence on the role of mesopic and dark-adapted scotopic microperimetry assessment in age-related macular degeneration. This scoping review summarises how mesopic and scotopic microperimetry can be used to assess disease progression in age-related macular degeneration and identifies gaps in the literature. METHODS: A population, concept, and context approach was used to develop the search strategy. Ovid MEDLINE, EMBASE, Cochrane Library, PubMed, CINAHL Plus, Web of Science, and SCOPUS databases were used to conduct the literature search. The key search terms used in the databases were age-related macular degeneration and microperimetry. RESULTS: Twelve studies were eligible and included in the review. All the studies (n = 12) were conducted in European countries [Germany (9), Italy (2), and the United Kingdom (1)]. The mesopic and scotopic sensitivities were measured using the Nidek scotopic microperimeter (MP1-S) (n = 6), scotopic Macular Integrity Assessment device (S-MAIA) (n = 5), and both MP1-s and S MAIA (n = 1). 83.3% (n = 10) studied (cross-sectional design) on mesopic, scotopic microperimetry and found reduced rod (scotopic) photoreceptors sensitivities compared to cone (mesopic) photoreceptors sensitivities in patients with small and reticular pseudodrusen despite having good visual acuity. Only 16.7% (n = 2) of studies followed participants with reticular drusen/large drusen for three years (longitudinal design) and found reduced scotopic over mesopic sensitivity at baseline and localized mesopic with profound scotopic sensitivity loss during follow-ups. CONCLUSION: Scotopic sensitivity is a better functional indicator than mesopic sensitivity to understand early and intermediate age-related macular degeneration progression. The evidence from longitudinal studies is debatable due to the limited stimuli range of existing microperimeters, smaller sample size, and lost follow-ups.

Fixation stability improvement after occlusion treatment for severe amblyopia.

BACKGROUND: To investigate the improvement of fixation stability of severe amblyopia with traditional patching treatment by the MP-1 microperimeter. METHODS: Eighteen patients with severe unilateral amblyopia were enrolled and received prescribed 6 h per day of patching of the fellow eye with optical correction if needed. Fixation test was performed on eighteen severe unilateral amblyopia patients by the MP-1 microperimeter in baseline, 3-month and 6-month after treatment. The bivariate contour ellipse area (BCEA, deg2) was used to quantify fixation stability. RESULTS: The RMANOVA showed that significant differences were found in best-corrected visual acuity (BCVA) between amblyopia eyes/fellow eyes (AE/FE) group (F = 113.52, p < 0.001) and among follow-up time (F = 74.684, p < 0.001). Moreover, a significant interaction could be found between AE/FE group and follow-up time (baseline/3-month/6-month, F = 60.189, p < 0.001). Post hoc analysis by Bonferroni showed significant improvement of BCVA in AE at 3-month (p < 0.001) and 6-month (p < 0.001), compared to baseline, and also significant between 3-month and 6-month (p = 0.002). The RMANOVA showed that significant differences were found in BCEA between AE/FE group (F = 8.432, p = 0.006) and among follow-up time (F = 10.431, p = 0.003). Moreover, a significant interaction could be found between AE/FE group and follow-up time (F = 9.099, p = 0.005). The mean BCEA of AE changed from 13.14 ± 17.97 deg2 at baseline to 6.03 ± 7.27 deg2 at 3-month (p = 0.084) and 3.38 ± 6.40 deg2 at 6-month (p = 0.018). No significant difference of BCEA in fellow eyes was found during the follow-up period (between baseline and 3-month: p = 0.230; between baseline and 6-month: p = 0.692. 0.89 ± 1.02, 0.58 ± 0.40, and 0.03 ± 0.04 deg2 for baseline, 3-month and 6-month, respectively). No significant correlation could be found between BCEA and BCVA of AE, both in enrollment and follow-up (p > 0.05). CONCLUSIONS: The fixation stability in the amblyopic eyes is significantly worse than that of the fellow eyes in patients with unilateral severe amblyopia. The fixation stability became better after 6-month occlusion treatment, but the change of fixation stability was not correlated with visual acuity improvement. These quantitative results highlight the importance of fixation in the mechanism of amblyopia.

An Overview of Preferred Retinal Locus and Its Application in Biofeedback Training for Low-Vision Rehabilitation.

Central vision loss (CVL) caused by macular damage generally disables common daily tasks, which cannot be reversed by present treatments. Fortunately, it has been found that biofeedback training by inducing or reinforcing preferred retinal locus (PRL) as an eccentric fixation reference contributes to the improvement of visual performance in patients with CVL. However, the clinical application is still under controversy due to poor knowledge of its fundamental and inconsistent practical standards. This article aims to summarize the possible rationale for the development, location, re-location and evaluating indicators of PRL, and the general apparatus, protocol, and outcome of biofeedback PRL training.

Changes in retinal sensitivity following inverted internal limiting membrane flap technique for large macular holes.

PURPOSE: The aim of this study was to evaluate the effect of inverted internal limiting membrane (ILM) flap technique and measure the retinal sensitivity using microperimetry-1 (MP-1) test in patients with large macular hole (MH). MATERIALS AND METHODS: We enrolled patients undergoing surgery for idiopathic MHs from January 2016 to October 2019. Only patients having a minimum diameter of idiopathic MH exceeding 500 µm were included in this study. All patients underwent complete preoperative ophthalmologic examinations, optical coherence tomography (OCT), and best-corrected visual acuity (BCVA) measurements. Postoperative OCT and BCVA were evaluated at least 3 months postoperatively. In addition, these patients also received MP-1 pre- and postoperatively for retinal sensitivity measurement. RESULTS: Totally ten patients (ten eyes) were included for analysis. The mean retinal sensitivity within central 12° and 40° was statistically improved after surgery (P < 0.05). The number of absolute or relative scotoma (stimulus values ≤4 dB) within central 4° showed a significant reduction postoperatively. There was also a significant increase in visual acuity postoperatively. CONCLUSION: Patients with large MH have a great successful rate by receiving inverted ILM flap technique. In our study, all MHs of ten eyes were closed postoperatively. The results also demonstrated that ILM flap technique improves both the functional and anatomic outcomes.

Biofeedback stimulation in the visually impaired: a systematic review of literature.

BACKGROUND: It is estimated that approximately 1.3 billion people live with some form of distance or near visual impairment. Numerous studies have been carried out to evaluate the effects of biofeedback (BF) and establish if it could be a useful tool in vision rehabilitation for various eye diseases. OBJECTIVE: This systematic review aimed: 1) to examine the current evidence of BF efficacy for the rehabilitation of the visually impaired and 2) to describe methodological variations used in previous BF studies to provide recommendations for vision rehabilitation interventions. METHODS: A systematic review was conducted in the Medline, PubMed, Cochrane Library and Web of Science databases to collect documents published between January 2000 and May 2020. Of the 1,960 studies identified, 43 met the criteria for inclusion. The following information was collected from each study: sample size, control group, any eye disease, apparatus used, frequency and number of sessions of BF, main outcomes of training and whether a follow-up was conducted. The first group included studies published as scientific articles in peer-reviewed journals. The second group included abstracts of studies presented at peer-reviewed conferences. Publications were also grouped according to the eye disease treated. RESULTS: 25 articles and 18 peer-reviewed conference abstracts (PRCAs) were included in this review. BF stimulation is a commonly used technique for the treatment of visual impairment caused by macular disease. Most BF studies evaluate the effect of training on the preferred retinal locus (PRL), particularly with regard to fixation location and stability. Across these studies, participants who received BF intervention improved fixation stability and reading speed. High variability in the number of sessions and the duration of BF training was found. Most studies did not use a control group. CONCLUSIONS: The findings of this review present evidence for biofeedback treatment in vision rehabilitation, with improved oculomotor abilities. Currently, it is not possible to formulate evidence-based recommendations for a standard training procedure due to the poor quality of existing randomised controlled trials. High-quality studies are needed to develop standard protocols for a range of eye diseases.

Fixation Characteristics of Severe Amblyopia with Eccentric Fixation and Central Fixation Assessed by the MP-1 Microperimeter.

OBJECTIVES: To investigate the fixation patterns in severe amblyopia with eccentric or central fixation by the MP-1 microperimeter. DESIGN: Fixation test was performed on 38 patients with severe amblyopia using the MP-1 microperimeter, 20 patients with eccentric fixation (EF group), and 18 patients with central fixation (CF group). Fixation location and fixation stability were quantified by preferred fixation eccentricity and bivariate contour ellipse area (BCEA, deg2) respectively. Comparisons of BCEA between amblyopic and fellow eyes (FE) in both groups and between amblyopic eyes (AE) in both groups were analyzed. Linear regression analysis was used to investigate the risk factors for fixation instability in patients with eccentric fixation. RESULTS: In EF group, the BCEA of AE was 14.68 ± 19.21 deg2, which was significantly larger than that of FE (1.294 ± 1.840, F = 9.243, p = .007). Linear regression analysis showed that only preferred fixation eccentricity (ß = 6.536, 95% CI: 2.665 ~ 10.406, p < .005) was correlated with BCEA of AE. The BCEA of AE in the EF group was significantly larger than that of AE in the CF group (4.95 ± 3.44 deg2, t = 2.227,p < .05), although the BCVA was not significantly different between two groups (t = 0.129, p = .898). CONCLUSIONS: The fixation ability in amblyopia with eccentric fixation was found to be significantly worse than those with central fixation and preferred fixation eccentricity was the only predictor for the instability. MP-1 is an effective tool to quantify fixation features for diagnosis and follow-up of eccentric amblyopia patients.

Microperimetric Biofeedback Training after Successful Inverted Flap Technique for Large Macular Hole.

Background: Despite the high closure rate of large macular hole (LMH) after surgery, visual recovery is often worse than expected. Microperimetric biofeedback can improve visual function in macular pathologies. We evaluated the efficacy of biofeedback on macular function after successful inverted flap technique for LMH. Methods: In this prospective comparative study, 26 patients after LMH surgical closure were enrolled. The whole sample was equally divided into two groups. In Group 1 (trained), patients underwent a double cycle of microperimetric biofeedback, using structured light stimulus plus acoustic tone; in Group 2 (control), patients underwent scheduled visits. We analyzed visual acuity, retinal sensitivity at central 12° (macular sensitivity, MS) and 4° (central macular sensitivity, CMS), and fixation stability over twelve months. Results: Visual acuity improved mainly in the trained group, without any significant differences between the groups (p > 0.05). Only after training did MS significantly improve (p = 0.01). CMS more significantly improved in the trained (p < 0.001) than the control group (p < 0.01) (Group 1 vs. 2, p = 0.004). Only in the trained group did fixation significantly improve (3 months, p ≤ 0.03; 12 months, p ≤ 0.01). An equality test on matched data confirmed a greater significant improvement of CMS (p ≤ 0.02) at all follow-up and fixation (p ≤ 0.02) at last follow-up after training. Conclusion: Microperimetric biofeedback consolidates and increases the improvement of retinal sensitivity and fixation gained after successful inverted flap technique.

Reproducibility of Microperimeter 3 (MP-3) Microperimetry in Open-Angle Glaucoma Patients.

PURPOSE: Primary open-angle glaucoma (POAG) is a chronic progressive optic neuropathy, leading to degeneration of retinal ganglion cells and characteristic morphological changes at the optic disc. In advanced stages of the disease, functional tests, such as standard automated perimetry (SAP), are the main diagnostic tools to detect progression. Compared to SAP, microperimetry offers fundus imaging with motion tracking to ensure precise stimulation of certain locations of the retina. Aim of the study was to assess reproducibility of microperimetry compared to SAP in patients with POAG. METHODS: This prospective monocenter study included patients suffering from POAG with visual field defects in the central 20° zone. After inclusion into the study, 3 consecutive study visits were scheduled within 1 month, assessing microperimetry and SAP at each visit. RESULTS: From 19 patients recruited, data from 18 patients could be analyzed. No significant difference between study visits could be detected in mean retinal sensitivity in microperimetry and SAP (microperimetry p = 0.401; SAP p = 0.644; Friedman's 2-way analysis of variance). The intraclass-correlation coefficient was 0.981 (95% CI 0.978-0.984) for microperimetry and 0.948 (95% CI 0.941-0.955) for SAP. Absolute agreement between deep scotoma points was found in 81 test locations (79%) in microperimetry and in 35 test locations (20%) in SAP (p = 0.003, chi-square test). CONCLUSIONS: Microperimetry and conventional perimetry showed high reproducibility, with slightly better performance of microperimetry. However, the reduced angle of visual field in microperimetry limits its application to central glaucomatous field damage.

Macula halo syndrome.

INTRODUCTION: Niemann-Pick disease (NPD) is a hereditary lysosomal storage disorder in which mutations in the sphingomyelin phosphodiesterase gene leads to partial or complete deficiency of the sphingomyelinase enzyme. Niemann-Pick Type B is the intermediate form associated with hepatosplenomegaly, foam cells in the bone marrow, hyperlipidemia and diffuse pulmonary infiltrates, which is generally diagnosed in late adolescence. Central nervous system is not affected, and some cases may display macular halo. CASE: A 45-year-old female seen in ophthalmology clinic for the examination of the eyes. Extraocular motility was normal bilaterally, and the visual acuity was 20/25 for both eyes. Biomicroscopic examination revealed faint corneal haze bilaterally, Circular pale granular depositions were detected in the parafoveal retina on both eyes. Optical coherence tomography (OCT) revealed thin hyperreflective band corresponding to depositions located in the parafoveolar inner retina. Microperimeter showed slight depression in retinal sensitivity, which was more pronounced particularly on perifovea rather than parafovea. CONCLUSIONS: Challenge to identify the NPD subtype of this case is associated with phenotypic characteristics on a wider spectrum that overlap the currently described subtypes.

Fixation Characteristics of Severe Amblyopia Subtypes: Which One is Worse?

PURPOSE: To determine differences in macular sensitivity and fixation patterns in different subtypes of severe amblyopia. METHODS: This case-control study enrolled a total of 73 male adults, including 18 with pure strabismic severe amblyopia, 19 with pure anisometropic severe amblyopia, 18 with mixed (strabismic plus anizometropic) severe amblyopia, and 18 healthy controls. MP-1 microperimetry was used to evaluate macular sensitivity, location of fixation, and stability of fixation. RESULTS: Mean macular sensitivity, stability of fixation, and location of fixation were significantly worse in all amblyopia subtypes when compared with healthy controls. Intergroup comparisons between amblyopia subtypes revealed that mean macular sensitivity, stability of fixation, and location of fixation were significantly worse in pure strabismic and mixed amblyopic eyes when compared with pure anisometropic amblyopic eyes. CONCLUSIONS: Strabismus seems to be a worse prognostic factor in severe amblyopia than anisometropia in terms of fixation characteristics and retinal sensitivity.

Reliability and Intersession Agreement of Microperimetric and Fixation Measurements Obtained with a New Microperimeter in Normal Eyes.

PURPOSE: To evaluate the reliability and intersession agreement of measurements of retinal sensitivity as well as of the fixation pattern obtained in healthy eyes with a microperimeter integrating the mechanism of the scanning laser ophthalmoscope (SLO) with the static perimetry. METHODS: This study included a sample of 44 healthy eyes of 44 subjects of a mean age of 27.0 ± 8.5 years. In all cases, microperimetric exams with the MAIA system (Centervue, Padova, Italy) were performed in three different sessions to evaluate the intersession repeatability. The consistency of measurements was analyzed by using the Friedman test and by analyzing the correlation between consecutive measurements. Agreement between the first and third sessions was assessed by using the Passing-Bablok regression analysis. The following parameters were analyzed: average threshold (AT), macular integrity (MI) index, fixation indexes P1 and P2, bivariate contour ellipse area (BCEA), major and minor axes of the ellipse and high preferred retinal locus position (PRLh). RESULTS: Not statistically significant differences were found in the evaluated parameters between the three sessions (p ≥ 0.193). The correlation between consecutive measurements was moderate to strong for all parameters evaluated (r ≥ 0.49, p < 0.01), except for the MI and the position of the PRLh (r ≤ 0.305, p ≥ 0.05). The Passing-Bablok regression analysis showed a good agreement between the first and third measurement for all parameters, except for the MI and the position of the PRLh. CONCLUSION: MAIA MP system is able to provide consistent measurements of AT and fixation in normal subjects. MI and the position of PRLh seem to be the least reliable parameters in this group of patients.

Retinal Sensitivity over Hard Exudates in Diabetic Retinopathy.

PURPOSE: To evaluate retinal sensitivity over hard exudates in correlation with the spectral domain optical coherence tomography (SD-OCT) findings in eyes with diabetic retinopathy. METHODS: Twelve eyes of 10 patients with hard exudates associated with diabetic retinopathy were enrolled in this study. All subjects underwent a complete ophthalmic examination including SD-OCT (Copernicus, Zawiercie, Poland) and microperimetry (MP1; Nidek Technologies, Padova, Italy). Retinal sensitivity was measured, over the areas with hard exudates and compared to corresponding locations devoid of hard exudates, using a semi-automatic program. The size of the hard exudate plaque was measured using the measurement software in the microperimeter. Retinal thickness in the area of the hard exudates and foveal thickness were measured using SD-OCT. RESULTS: Mean retinal sensitivity over hard exudates was 4.97 ± 4.17 dB which was significantly (P = 0.0001) reduced as compared to locations devoid of hard exudates. No significant correlation (r=-0.23, P = 0.45) was found between the size of the hard exudates and retinal sensitivity. A significant negative correlation was found between retinal sensitivity and retinal thickness at the area of the hard exudates (r=-0.65, P = 0.05), and between retinal sensitivity and foveal thickness (r=-0.91, P = 0.001). CONCLUSION: In eyes with diabetic retinopathy, retinal sensitivity was reduced due to the presence of hard exudates in the outer retinal layers and retinal thickening but this was not correlated with the size of the hard exudates.