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

Quantifying the Relationship Between Unilateral Induced Metamorphopsia and Stereopsis Impairment

Purpose

To investigate the relationship between unilateral metamorphopsia, characterized by visual distortions in one eye, and impaired stereopsis.

Methods

Utilizing both near and distance measurements through advanced testing systems, including 4K smartphones and an active shutter three-dimensional system, we simulated varying degrees of unilateral metamorphopsia in 30 healthy young adults aged between 21 and 29 years. Two types of contour-based stereotest symbols, lines and squares, were developed. Distortions were classified into six distinct patterns, each further divided into eight grades of severity. Participants were tasked with identifying visual targets, and their stereothresholds were determined under different conditions of induced distortion. Stereopsis was measured within a range of 2.9 to 1.0 log arcsec, at 0.2 log arcsec intervals. Stereopsis changes under different distortion scenarios were analyzed using the generalized estimating equations, with a sequential Bonferroni adjustment applied for pairwise comparisons.

Results

A direct and quantifiable correlation was observed between the severity of metamorphopsia and reductions in stereopsis. As the degree of visual distortion increased, notably in both frequency and amplitude, there was a corresponding decline in stereopsis. This relationship held true in both near and distance measurements of stereopsis. Statistical analyses further reinforced these findings, highlighting a significant detrimental effect of distortion components on stereoacuity.

Conclusions

The findings highlight the clinical significance of understanding the interplay between unilateral metamorphopsia and stereopsis. Early interventions in conditions leading to metamorphopsia might be critical to maintaining optimal stereopsis.

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.

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 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.

Stereopsis After Unilateral Macular Hole Surgery with Internal Limiting Membrane Peeling

Purpose

We have shown distinct morphological changes of the foveal retina such as horizontally asymmetrical retinal thicknesses and displacements of the fovea toward the optic disc after successful idiopathic macular hole (MH) closure by MH surgery with internal limiting membrane (ILM) peeling. The purpose of this study was to determine whether these morphological changes will alter the stereoacuity.

Setting

This was a non-randomized, retrospective study conducted on patients who underwent MH surgery at the Matsumoto Dental University Hospital, Nagano, Japan.

Methods

Forty patients (22 women, 18 men) who underwent MH surgery with ILM peeling for a unilateral MH were studied. At >6 months after the PPV, the stereoacuity was measured with the Titmus stereotest (TST) and the TNO stereotest (TNO). The relationship between the stereoacuity and the age, MH size, best-corrected visual acuity (BCVA), foveal retinal thickness, and amount of nasal shift of the retina was determined.

Results

The mean postoperative BCVA was −0.05 ± 0.11 logarithm of the minimum angle of resolution (logMAR) units. The percentage of cases with good stereoacuity of ≤100 sec of arc was 87.5% with the TST and ≤240” was 90% with the TNO test. A better stereoacuity was significantly correlated with a younger age (r = 0.36, P <0.05; with TNO), smaller MH (r = 0.51, P < 0.001, with TST), better postoperative BCVA (r = 0.43 P <0.01 with TST; r = 0.49, P <0.01 with TNO), but not with the parafoveal retinal thickness or degree of nasal shift.

Conclusion

The postoperative stereopsis is relatively good in patients with better postoperative BCVA after MH surgery with ILM peeling, even though foveal morphological changes had occurred.