STEREOPSIS AND OPTICAL COHERENCE TOMOGRAPHY FINDINGS AFTER EPIRETINAL MEMBRANE SURGERY

Measurement of paracentral stereopsis using a new method with the binocular open perimeter imovifa® in normal adults

PURPOSE

No method to quantitatively evaluate stereopsis within the 15º visual field has been clinically established. We developed a program to measure paracentral stereopsis and evaluated its feasibility in visually normal participants.

STUDY DESIGN

Experimental investigation METHODS: Ten visually normal volunteers with stereopsis of 60 arcseconds or better were included. The Stereo Eccentricity Analysis (SEA) program for stereopsis measurement across the visual field was integrated into the binocular visual field analyzer imovifa®. Subjects with established binocular stereopsis detected a stereoscopic circular target presented with crossed disparity on random dots at the fovea, 3°, 5°, 10°, and 15° on the 45°, 135°, 225°, and 315° meridians. The subjects performed two tasks for measurement in the periphery: a detection task by pressing the response button when the circular target was perceived and a localization task by tilting a joystick to indicate in which quadrant the circular target was perceived. The duration of the target presentation was 500 ms.

RESULTS

The stereo thresholds at 0º and 3° did not significantly differ. The thresholds at 10º and 15º were significantly higher than at 0° (P < 0.01). While no inter-individual threshold difference was observed at the fovea, the difference was large at 15°. The stereo thresholds for the detection and localization tasks also did not differ significantly.

CONCLUSION

With the SEA program, paracentral stereopsis can be measured and the stereo threshold increases with eccentricity. The SEA program appears to be a feasible clinical method to evaluate paracentral stereopsis.

Optical coherence tomography parameters as prognostic factors for stereopsis after vitrectomy for unilateral epiretinal membrane: a cohort study

This retrospective cohort study explored the relationship between monocular and interocular optical coherence tomography (OCT) parameters and stereopsis in 56 patients undergoing pars plana vitrectomy (PPV) for unilateral idiopathic epiretinal membrane (IERM). IERM impairs visual functions, with symptoms ranging from asymptomatic to severe impairment. Despite established surgical interventions, including PPV with membrane peeling, the impact on advanced three-dimensional visual functions such as stereopsis remains inadequately investigated. All subjects were assessed for stereopsis, visual acuity, and metamorphopsia, alongside spectral domain OCT parameters. These visual functions significantly improved 3-month postoperatively. Central retinal thickness at the fovea, parafovea, and perifovea (CFT, CRT-3 mm, and CRT-6 mm), ectopic inner foveal layer thickness, and retinal layer thickness notably decreased 1 week to 3 months after surgery. The interocular difference in OCT parameters between bilateral eyes was included as a parameter. Baseline CRT-3 mm difference and inner nuclear layer (INL) thickness were independently correlated with postoperative stereopsis on the Titmus Stereo Test, while baseline CRT-6 mm difference and INL thickness were independently related to stereopsis on the TNO stereotest. This study highlights the substantial enhancement in stereopsis post-IERM surgery, with both interocular and monocular OCT parameters independently influencing postoperative stereopsis. These findings underscore the importance of retinal microstructures in assessing and predicting stereopsis in IERM patients after vitrectomy.

Comparison of stereopsis and foveal microstructure after internal limiting membrane peeling and inverted internal limiting membrane flap techniques in patients with macular hole

PURPOSE

To compare stereopsis and foveal microstructure after internal limiting membrane peeling and inverted internal limiting membrane flap technique in patients with macular hole.

DESIGN

Retrospective observational study.

METHODS

Sixty-six patients with macular hole were included, of whom 41 underwent 25-gauge pars-plana vitrectomy with complete internal limiting membrane peeling (Peeling group) and 25 with the inverted flap technique (Inverted group). We evaluated stereopsis using the Titmus Stereo Test and the TNO stereo test, best-corrected visual acuity, macular hole closure rate, and foveal microstructure with optical coherence tomography before and at 3, 6, and 12 months after surgery.

MAIN OUTCOME MEASURES

Stereopsis and foveal microstructure.

RESULTS

Preoperatively, no difference was observed in the base and minimum diameters of macular hole, Titmus Stereo Test score, TNO stereo test score, and best-corrected visual acuity between the Peeling and Inverted groups. The macular hole closure rate in the Peeling and Inverted groups were 97.6% and 100%, respectively, with no significant difference between groups. At 12 months postoperatively, Titmus Stereo Test score (2.1 ± 0.4 in the peeling and 2.2 ± 0.4 in the inverted groups), TNO stereo test score (2.3 ± 0.4 and 2.2± 0.5), and best-corrected visual acuity (0.20 ± 0.18 and 0.24 ± 0.25) were not significantly different between groups (p = 0.596, 0.332, respectively). The defect of the external limiting membrane was more common in the Inverted group than in the Peeling group at 6 months after surgery (5.4 vs. 28.0%; p < 0.05). No statistically significant inter-group differences were noted in the ellipsoid zone defect ratio throughout the follow-up period.

CONCLUSIONS

There was no difference in postoperative stereopsis nor foveal microstructure between the internal limiting membrane peeling group and the inverted group in patients with macular hole.

Binocular visual function improvement after pars plana vitrectomy for epiretinal membrane

PURPOSE

To report binocular visual function changes after pars plana vitrectomy for epiretinal membrane (ERM) and the related outcomes.

METHODS

Twenty-three eyes of 23 patients operated on for ERM were included in a retrospective study. Clinical data, best-corrected visual acuity (BCVA), contrast sensitivity and binocular visual function were assessed pre- and 1 and 3 months post-operatively. Binocular visual function assessment included the evaluation of fusional amplitudes (i.e., vergences) by the synoptophore, far distance stereopsis using polarized glasses and near stereopsis using Randot and TNO tests. Central macular thickness (CMT) was measured on Spectral Domain - Optical Coherence Tomography.

RESULTS

Mean age of the patients was 67 years. Mean BCVA and contrast sensitivity significantly improved post-operatively at one (p = 0.0006 and p = 0.0022, respectively) and 3 months (p < 0.0001 and p < 0.0001, respectively), while CMT significantly decreased after 1-3 months (p < 0.0001 and p < 0.0001, respectively). Fusional amplitudes improved after 3 months (p < 0.0001). Far distance and near stereopsis significantly improved after 3 months (p < 0.0001 and p = 0.0007 for Randot test, and p < 0.0001 for TNO test, respectively).

CONCLUSIONS

Pars plana vitrectomy for ERM surgery leads to an improvement of monocular and binocular visual functions (i.e., binocular fusion, near and far distance stereopsis), within 3 months post-operatively.

Correlation between Central Visual Field Defects and Stereopsis in Patients with Early-to-Moderate Visual Field Loss

PURPOSE

To investigate the association between stereoacuity and the presence of central visual field defects (CVFDs) due to glaucoma.

DESIGN

A prospective, cross-sectional cohort study.

PARTICIPANTS

Participants with early-to-moderate glaucoma with a visual acuity better than 20/40, less than a 2-line difference in visual acuity between eyes, and 2 reliable Humphrey visual fields (VFs) (24-2 SITA standard) with mean deviation (MD) in the worse eye better than - 12 dB.

METHODS

Stereoacuity was measured using the Titmus stereo test. Participants with a significant field defect (P < 0.005) in any 1 of the central 4 points in the 24-2 SITA standard total deviation map in either eye were classified as having a CVFD. Vision-related quality of life (VR-QOL) was measured using 25-item National Eye Institute Visual Function Questionnaire scores. Logistic regression was used to determine the associations between the level of stereoacuity and age, sex, race, glaucoma type, presence of CVFDs, visual acuity, contrast sensitivity, and VF MD.

MAIN OUTCOME MEASURES

Stereoacuity in the CVFD and non-CVFD groups.

RESULTS

Sixty-five participants met the inclusion criteria. The mean age of the participants was 64.3 ± 8.0 years, and 64.6% were women. The median stereoacuity was 60 arc seconds (interquartile range [IQR], 40-120 arc seconds). Forty-two (65%) patients had CVFDs, and 23 (35%) patients did not. The median stereoacuity of the CVFD group was worse than that of the non-CVFD group (60 arc seconds [IQR, 50-140 arc seconds] vs. 40 arc seconds [IQR, 40-80 arc seconds], respectively; P = 0.001). The non-CVFD group had a higher percentage of participants with normal stereopsis than the non-CVFD group (61% vs. 21%, respectively; P = 0.001). A multivariable analysis found that the presence of CVFDs was associated with worse stereopsis levels (odds ratio, 4.49; P = 0.021). The CVFD group had a lower Visual Functioning Questionnaire-25 (VFQ-25) composite score (84.0 vs. 91.4; P = 0.004) and lower VFQ-25 subscale scores for general vision, near activities, and mental health (P < 0.05).

CONCLUSIONS

Central visual field defects were associated with increased odds of poor stereoacuity in patients with early-to-moderate glaucomatous VF loss. Specifically, patients without CVFDs are more likely to have normal stereopsis and higher VR-QOL than those with CVFDs. Patients with CVFDs should be counseled regarding how depth perception difficulties may affect daily living.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Vision-Related Parameters Affecting Stereopsis after Retinal Detachment Surgery

Even after successful surgery, the stereopsis of retinal detachment (RD) patients is inferior to that of normal subjects. However, it is unclear which visual dysfunction in the affected eye is responsible for the postoperative stereopsis impairment. This study included 127 patients after successful surgery for unilateral RD. Stereopsis, best-corrected visual acuity (BCVA), severity of metamorphopsia, letter contrast sensitivity and amount of aniseikonia were examined at 6-month postoperatively. Stereopsis was assessed using the Titmus Stereo Test (TST) and TNO stereotest (TNO). Postoperative stereopsis (log) in patients with RD were 2.09 ± 0.46 in the TST and 2.56 ± 0.62 in the TNO. Multivariate analysis with stepwise regression revealed postoperative TST was associated with BCVA, and TNO was associated with BCVA, letter contrast sensitivity, metamorphopsia and absolute values of aniseikonia. In a subgroup analysis that selected those with more impaired stereopsis, postoperative TST was associated with BCVA (p < 0.001), and TNO was associated with letter contrast sensitivity (p < 0.005) and absolute values of aniseikonia (p < 0.05) by multivariate analysis. Deterioration of stereopsis after RD surgery was affected by a variety of visual dysfunctions. The TST was affected by visual acuity, while the TNO was affected by contrast sensitivity and aniseikonia.

Relationship between stereopsis and vision-related quality of life in patients with branch retinal vein occlusion

Background

To investigate the relationship between stereopsis and vision-related quality of life (VR-QOL) in patients with branch retinal vein occlusion (BRVO) before and after treatment with intravitreal ranibizumab (IVR).

Methods

This prospective multicentred observational study included 37 patients undergoing IVR treatment for unilateral BRVO and 24 age-matched healthy controls.

Stereopsis was evaluated using the TNO stereo test (TNO) and Titmus stereo test (TST) every month, and the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) was administered at baseline, then at 3, 6 and 12 months after treatment.

Results

Time course of the changes in stereopsis and VR-QOL. IVR treatment significantly reduced central fovea thickness and improved both the TNO and the TST from 2 to 12 months (both p<0.05). Stereopsis before and after IVR injection in the eyes with BRVO were significantly worse than those in control subjects (TNO, p<0.001; TST, p<0.001). The VFQ-25 composite score significantly improved from 3 to 12 months after IVR treatment (p<0.05). Univariate analysis showed that the TNO score at baseline was significantly correlated with the VFQ-25 composite score at baseline and after treatment (p<0.05, p<0.05, respectively). TST score was not associated with the VFQ-25 composite score at baseline or after treatment.

Conclusions

Treatment with IVR for BRVO improved cystoid macular oedema, which was correlated to improved stereopsis, although not to the control level. The TNO score at baseline was associated with VR-QOL in patients with BRVO.

Long-term functional outcomes and vision-related quality of life after vitrectomy for epiretinal membrane: a prospective cohort study

To investigate the long-term effect of unilateral idiopathic epiretinal membrane (uiERM) removal on monocular and binocular visual function, and on vision-related quality of life (VR-QoL). Prospective, single-center study. The following data were collected before and after surgery: distance monocular and binocular best-corrected visual acuity (BCVA), horizontal and vertical metamorphopsia, horizontal and vertical aniseikonia, stereoacuity and National Eye Institute Visual Function Questionnaire-25 item (NEI VFQ-25). Forty-two patients (mean age: 72.7 ± 7.4 years; 24 men) were included. At 6 months postoperatively, distance monocular BCVA (p < 0.001), horizontal metamorphopsia (p = 0.001) and the composite score of NEI VFQ-25 (p < 0.001) significantly improved, in comparison to baseline. At 2 years postoperatively, distance monocular (p < 0.001) and binocular (p = 0.01) BCVA, horizontal (p < 0.001) and vertical (p = 0.02) metamorphopsia, vertical aniseikonia (p = 0.01), stereoacuity (p < 0.001) and 3 subscales scores of the NEI VFQ-25 (p < 0.05) (“general vision”, “mental health”, “driving”) significantly improved in comparison to baseline. Removal of uiERM improves VR-QoL and achieves good visual outcomes on both monocular and binocular visual parameters over long-term. Visual symptoms induced by macular contraction have different improvement kinetics after surgery. Stereopsis, the highest level of binocular vision, can be improved in some cases.

Visual functions affecting stereopsis in patients with branch retinal vein occlusion

PURPOSE

To quantify stereopsis and other visual functions in patients with unilateral branch retinal vein occlusion (BRVO) and to investigate vision-related parameters that affect stereopsis.

DESIGN

Prospective observational study.

SUBJECTS

Forty-five patients undergoing intravitreal ranibizumab (IVR) treatment for unilateral BRVO.

METHODS

We examined stereopsis using the Titmus stereo test (TST) and TNO stereotest (TNO), best corrected visual acuity (BCVA), letter contrast sensitivity, severity of metamorphopsia and degree of aniseikonia before and 6 months after IVR.

MAIN OUTCOME MEASURES

Visual functions that affect stereopsis.

RESULTS

Baseline stereopsis in patients with BRVO was 2.7 ± 0.6 (range, 1.6-3.5) in the TST and 2.8 ± 0.5 (range, 1.8-3.3) in TNO. TST and TNO scores were significantly correlated with BCVA and letter contrast sensitivity at baseline (P < 0.001) but not with other visual functions. IVR treatment significantly improved stereopsis, BCVA, and letter contrast sensitivity. After treatment, TST scores were significantly correlated with BCVA (P < 0.001), letter contrast sensitivity (P < 0.001), and aniseikonia (P < 0.01). TNO scores were significantly correlated with BCVA (P < 0.01) and letter contrast sensitivity (P < 0.01). TST and TNO scores after treatment were significantly correlated with BCVA at baseline (P < 0.01 for both).

CONCLUSIONS

Deterioration of stereopsis in patients with BRVO was associated with changes in visual acuity and contrast sensitivity after treatment. Initial visual acuity is a prognostic factor for posttreatment stereopsis.

Relationship between stereopsis and vision-related quality of life following intravitreal ranibizumab injections for central retinal vein occlusion

The study aimed to evaluate changes in stereopsis and vision-related quality of life (VR-QOL) in patients with central retinal vein occlusion (CRVO) following intravitreal ranibizumab injection (IVR) and investigate the relationship between stereopsis and VR-QOL. This study included 23 treatment-naïve patients with non-ischemic CRVO and 13 age-matched normal controls. Stereopsis, best-corrected visual acuity (BCVA), VR-QOL, and retinal microstructures were examined pre-treatment and 12 months post-treatment. The Titmus Stereo Test (TST) and TNO stereotest (TNO) were used to evaluate stereopsis. VR-QOL was evaluated using the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25). IVR immediately and significantly improved the TST values, TNO values, composite VFQ-25 score, BCVA, and central foveal thickness in patients with CRVO. The 12-month post-treatment TST and TNO values were significantly worse in the CRVO group compared to those in the normal group. At the baseline, the composite VFQ-25 score significantly correlated only with the TST value. Multivariate analysis revealed significant associations between the 12-month post-treatment composite VFQ-25 score and the baseline and 12-month post-treatment TNO values. In conclusion, IVR immediately improved stereopsis in CRVO, albeit below normal levels. Stereopsis (not visual acuity) was associated with pre- and post-treatment VR-QOL in patients with CRVO.

Evaluation of postoperative visual function based on the preoperative inner layer structure in the epiretinal membrane

PURPOSE

To evaluate the postoperative visual function using a preoperative epiretinal membrane (ERM) classification based on the status of the inner layer structure.

METHODS

We assessed 62 eyes, one from each patient undergoing vitrectomy with internal limiting membrane (ILM) peeling for unilateral ERM. The inclusion criteria were as follows: (1) the presence of idiopathic ERM based on optical coherence tomography and a healthy contralateral eye, (2) successful surgery after 25- or 27-gauge transconjunctival 3-port pars plana vitrectomy with ILM peeling, and (3) a minimum follow-up period of 12 months. We included patients with preoperative ERM morphology with no disruption of the inner retinal layer in group A (37 eyes) and those with disruption in group B (25 eyes) and compared the visual acuity, central visual-field sensitivity (CVFS) measured using the Humphrey field analyzer 10-2 program, and detection rate of micro-scotoma (< 10 dB) at baseline and 12 months postoperatively between the groups.

RESULTS

Visual acuity at 12 months showed greater improvement in group A than in group B (P = .03). There was no significant difference in CVFS at baseline; however, that of the nasal area was substantially lower after surgery in group B than in group A (P = .02). The 12-month postoperative detection rate of micro-scotoma was significantly higher in group B than in group A (P = .002).

CONCLUSION

ERM that has preoperatively disrupted the inner layer poses the risks of CVFS reduction and micro-scotoma formation after vitrectomy. Evaluating the inner layer could be an important prognostic factor in determining retinal function in ERM.

Clinical and Optical Coherence Tomography Analysis of Intraretinal Microcysts in Patients with Epiretinal Membrane

Purpose: To perform clinical and optical coherence tomography analysis of intraretinal microcysts (IRM) in patients undergoing pars plana vitrectomy (PPV) for primary epiretinal membrane (ERM) treatment.Materials and Methods: The files of 137 patients who were operated on by a single surgeon for primary epiretinal membrane treatment in our clinic between September 2017 and January 2020 were retrospectively reviewed. Patients with ERM due to secondary pathology were excluded from the study. Twenty patients with post-operative IRM (group 1) were determined and were included as the study group. To determine the effect of IRMs on visual acuity 20 patients who did not have IRM, had primary ERM and underwent PPV for treatment were included as the control group (group 2). The demographic, clinical, and operative data of the patients were obtained from the hospital database. Retinal analysis of the patients before the operation and at the earliest 6 months after the operation was performed using 6 × 6 mm images taken with the macular cube 512 × 128 protocol on the Cirrus HD-OCT (Carl Zeiss Meditec, Dublin, CA, USA) device in our clinic.Results: Intraretinal microcysts were present in 8 (5.8%) of preoperative 137 patients and 20 (14.6%) of 137 postoperative patients. All 8 patients with preoperative cysts in group 1 also had postoperative IRMs. Excluding patients with preoperative cysts, the postoperative IRM incidence was found to be 12/137 (8.75%). Preoperative (p = .392) and postoperative (p = .978) visions were similar in group 1 and group 2. Preoperative (p = .745) and postoperative retinal thicknesses were similar in both groups (p = .989). The incidence of postoperative (p = .642) IRM was similar in patients who underwent ERM and ERM + internal limiting membrane (ILM) peeling in group 1.Conclusions: Intraretinal microcysts may sometimes be seen before and after ERM surgery. The preoperative cyst presence in ERM patients is an important risk factor for postoperative cyst presence. The peeling of ILM with ERM does not increase the probability of IRM occurrence. The presence of these cysts before and/or after the operation does not affect the visual prognosis and macular thickness in ERM patients.

[Optical coherence tomography biomarkers in epimacular membranes and vitreomacular traction syndrome]

Using high-resolution imaging, such as optical coherence tomography (OCT), the different layers of the retina as well as the vitreoretinal interface and its alterations can be very clearly differentiated. This includes the morphological characteristics of tractive maculopathies, such as epiretinal gliosis and vitreomacular traction syndrome. Additionally, structural alterations of the various layers of the neurosensory retina as a result of traction due to these pathologies can be demarcated. The latter have been investigated in clinical trials and evaluated as OCT biomarkers with respect to their prognostic and predictive value. In this review we would like to present and discuss various OCT biomarkers in the context of epimacular membranes and vitreomacular traction syndrome.

Stereopsis and retinal microstructures following macular hole surgery

The aim of this prospective study was to evaluate the changes in stereopsis in patients who underwent vitrectomy for macular hole (MH) and assess the relationship between stereopsis and retinal microstructures. Fifty-two patients who underwent successful vitrectomy for unilateral MH and 20 control participants were recruited. We examined stereopsis using the Titmus Stereo Test (TST) and TNO stereotest (TNO), optical coherence tomography, and best-corrected visual acuity measurements, preoperatively, and at 3, 6, and 12 months postoperatively. As a result, preoperative and postoperative 3, 6, and 12-month values of stereopsis assessed by TST (log) were 2.7, 2.2, 2.2, and 2.2, respectively. TNO (log) were 2.8, 2.5, 2.4, and 2.4, respectively. Stereopsis in MH after surgery was significantly worse than that in normal participants (p < 0.001). Preoperative TST significantly correlated with MH size and defect length of external limiting membrane (ELM). Postoperative TST demonstrated significant correlation with the preoperative ELM defect length, and postoperative TNO was associated with the preoperative interdigitation zone defect length. Vitrectomy for MH significantly improved stereopsis, although not to normal levels. The ELM defect lengths, which approximately correspond to TST circles, are prognostic factors for postoperative stereopsis by TST. The interdigitation zone defect length, similar in size to the TNO index, is a prognostic factor for postoperative stereopsis by TNO.

Evaluation of pre- and post-surgery reading ability in patients with epiretinal membrane: a prospective observational study

Background

This study aimed to investigate the pre- and post-surgery reading ability in patients with idiopathic epiretinal membrane (ERM) to evaluate whether measurement of reading performance is a helpful test in addition to visual acuity (VA) as an assessment measure.

Methods

This prospective observational study involved 42 eyes of 40 patients with idiopathic ERM. Best-corrected visual acuity (BCVA), reading ability, and metamorphopsia score were evaluated at baseline and at 3, 6, and 12 months post-surgery. As the outcome measure, the reading ability of each patient (i.e., overall performance) was examined with MNREAD-J, the Japanese version of the MNREAD reading acuity (RA) charts, to determine RA, critical print size (CPS), and maximum reading speed (MRS). Generally, a difference of 0.2 logMAR or more is considered a significant change in BCVA. Thus, as a subgroup analysis, we additionally evaluated the BCVA and reading ability of the patients with a BCVA difference of 0.1 logMAR or less between at baseline and at 12 months post-surgery.

Results

Relative to their values at baseline, the subjects exhibited significantly improved BCVA, RA, and CPS throughout the post-surgery examination period (P < 0.001) and significantly improved MRS at 12 months post-surgery (P = 0.04). No significant change in the vertical metamorphopsia score was observed throughout the post-surgery follow-up period. However, and compared to the value at baseline, significant improvements in the horizontal metamorphopsia score were observed at 3, 6 (P < 0.05), and 12 months (P < 0.001) post-surgery. In the subgroup analysis of the 23 eyes that exhibited a BCVA improvement of 0.1 logMAR or less, the median BCVA did not change, but the median RA and CPS improved by 0.2 logMAR.

Conclusions

Our findings showed that the surgical removal of ERM improves reading ability, even when the BCVA score does not improve. The measurement of reading performance appears to be a helpful test in addition to VA as a measure for assessing the surgical removal of ERM.

Preoperative aniseikonia is a prognostic factor for postoperative stereopsis in patients with unilateral epiretinal membrane

PURPOSE

To investigate stereopsis and other visual functions in patients with unilateral epiretinal membrane (ERM) and to identify vision-related parameters affecting stereopsis.

METHODS

This prospective study included 63 consecutive patients who were scheduled to undergo vitrectomy for unilateral idiopathic ERM. We examined stereopsis (Titmus Stereo Test, TST; TNO stereotest, TNO), best-corrected visual acuity (BCVA), letter contrast sensitivity, severity of metamorphopsia, and degree of aniseikonia preoperatively and 6 months postoperatively.

RESULTS

Preoperatively, we observed significant correlation between TST scores and other vision-related parameters except severity of metamorphopsia and between TNO score and all the vision-related parameters. Multiple regression analysis showed that preoperative TST and TNO scores were significantly associated with the degree of aniseikonia (both P < 0.01). ERM surgery significantly improved stereopsis, BCVA, contrast sensitivity, and metamorphopsia, but not aniseikonia. Postoperatively, TST was significantly associated with BCVA, and TNO showed association with BCVA and aniseikonia. Postoperative TST and TNO scores showed significant correlation with preoperative aniseikonia (P < 0.005 and P < 0.001, respectively).

CONCLUSIONS

Impairment of stereopsis in patients with unilateral ERM was considered to be due to retinally induced aniseikonia. Aniseikonia did not improve by surgery, and preoperative aniseikonia can be a prognostic factor for postoperative stereopsis.

Vision-related parameters that affect stereopsis in patients with macular hole

This study evaluated stereopsis and other visual functions in patients with idiopathic macular hole (MH), and sought to identify vision-related parameters that affect stereopsis. In this prospective, consecutive, comparative study, 39 eyes of 39 patients with unilateral idiopathic MH were included. At baseline and at 6 months after MH surgery, we evaluated stereopsis, with the Titmus stereo test (TST) and TNO stereotest (TNO), best-corrected visual acuity (BCVA), letter contrast sensitivity, severity of metamorphopsia, as assessed using M-CHARTS, and extent of aniseikonia, by the new aniseikonia test. Preoperative stereopsis (log) in patients with MH were 2.72 ± 0.53 (range 1.9–4.1) in the TST and 2.82 ± 0.65 (range 1.8–3.9) in the TNO. Preoperative TST was significantly correlated with letter contrast sensitivity (p < 0.05), but not with the other visual functions. TNO showed significant correlation with letter contrast sensitivity (p < 0.05) and aniseikonia (p < 0.005). Preoperative TNO was associated with aniseikonia by multivariate analysis (p < 0.005). MH surgery significantly improved stereopsis, BCVA, letter contrast sensitivity, metamorphopsia, and aniseikonia. Postoperative TST and TNO was significantly associated with BCVA by multivariate analysis. Deterioration of stereopsis in MH patients is associated with contrast sensitivity and the degree of aniseikonia.

Prospective study of vitrectomy for epiretinal membranes in patients with good best-corrected visual acuity

Background

To evaluate the efficacy of epiretinal membrane removal in patients with good best-corrected visual acuity (BCVA) for improving visual function and quality of life (QOL).

Methods

This prospective case study compared 37 subjects with preoperative BCVA ≦ 0.046 logMAR (Good group) to 35 patients with 0.10–0.52 logMAR (Moderate group) at 3 and 6 months. Linear mixed-effect models were used for statistical analysis. The primary outcome was the horizontal metamorphopsia score (MH) at 6 months postoperatively (post-6 M), while secondary outcomes were postoperative BCVA, vertical metamorphopsia score (MV), aniseikonia, stereopsis and central foveal thickness. In the Good group, QOL was assessed using the National Eye Institute Visual Functioning Questionnaire-25 (NEI VFQ-25) at 6 and 12 months.

Results

MH was significantly improved at post-3 M and post-6 M in the both groups but there were no significant differences between the two groups. MV showed no improvement at the final observation in either group. LogMAR BCVA was significantly improved at post-6 M in the Good group, which had significantly better vision than the Moderate group. Preoperative vertical and horizontal aniseikonia scores remained unchanged in the Good group at post-6 M but worsened in the Moderate group. The NEI VFQ-25 score improved in the Good group, reflecting improved general health, general vision, and mental health.

Conclusions

Early epiretinal surgery for patients with BCVA ≦ 0.046 logMAR was effective for improvement of HM, BCVA, and QOL and prevented worsening of aniseikonia.

Trial registration

UMIN000021220. Registered 10 September 2015.

UMIN Clinical Trials Registry.

Idiopathic epiretinal membrane surgery: safety, efficacy and patient related outcomes

This review aims to give to the reader an overview selectively oriented on safety and efficacy of surgery, providing concise and direct answers about crucial questions of trainees and experts. Surgery for idiopathic epiretinal membrane (ERM) is a safe and effective procedure that can achieve long-term stable postoperative visual and anatomical improvement, with an overall low recurrence and complication rate. Young patients, with a short onset of symptoms and with better initial visual acuity achieve higher levels of visual outcome. The preoperative degree of metamorphopsia is the prognostic factor for their postoperative degree. Successful results may be obtained in eyes with specific optical coherence tomography criteria, such as thin ganglion cell layers, thin internal plexiform layer, longer photoreceptors outer segment, regular ellipsoid zone and cone outer segment tips line, and without ectopic inner foveal layer. Internal limiting membrane peeling demonstrates positive anatomical and functional outcomes, but final positions about its safety remain controversial.