Effect of Cataract Extraction on Retinal Sensitivity Measurements

A New Approach to Staging Diabetic Eye Disease: Staging of Diabetic Retinal Neurodegeneration and Diabetic Macular Edema

Topic

The goal of this review was to summarize the current level of evidence on biomarkers to quantify diabetic retinal neurodegeneration (DRN) and diabetic macular edema (DME).

Clinical relevance

With advances in retinal diagnostics, we have more data on patients with diabetes than ever before. However, the staging system for diabetic retinal disease is still based only on color fundus photographs and we do not have clear guidelines on how to incorporate data from the relatively newer modalities into clinical practice.

Methods

In this review, we use a Delphi process with experts to identify the most promising modalities to identify DRN and DME. These included microperimetry, full-field flash electroretinogram, spectral-domain OCT, adaptive optics, and OCT angiography. We then used a previously published method of determining the evidence level to complete detailed evidence grids for each modality.

Results

Our results showed that among the modalities evaluated, the level of evidence to quantify DRN and DME was highest for OCT (level 1) and lowest for adaptive optics (level 4).

Conclusion

For most of the modalities evaluated, prospective studies are needed to elucidate their role in the management and outcomes of diabetic retinal diseases.

Financial Disclosures

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

Clinical utilization of microperimetry in ophthalmic surgery: A narrative review

Microperimetry is an emerging technology that provides concurrent analysis of retinal structure and function by combining retinal sensitivity and fixation analysis with fundus imaging. We summarize the substantial evidence validating the evolving role of microperimetry as an adjunctive assessment of visual function in the perioperative setting. We show that microperimetry provides useful complementary information to other established imaging and functional modalities in the perioperative setting for a wide range of vitreoretinal surgical procedures, as well as in cataract and refractive surgeries. This includes preoperative uses such as prognostication of visual and anatomical outcomes, timing of surgical intervention, and assessment of patient suitability for surgery-as well as postoperative uses including quantification of visual recovery, investigation of unexplained postoperative vision loss, and informing expected long term functional 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.

Dissociated Optic Nerve Fiber Layer Appearance after Macular Hole Surgery: A Randomized Controlled Trial Comparing the Temporal Inverted Internal Limiting Membrane Flap Technique with Conventional Peeling

PURPOSE

To evaluate the effect of the temporal inverted internal limiting membrane (ILM) flap technique compared with that of conventional ILM peeling on the extent of the dissociated optic nerve fiber layer (DONFL) and retinal sensitivity in patients undergoing macular hole (MH) surgery.

DESIGN

Single-center, prospective, open-label, randomized controlled clinical trial.

PARTICIPANTS

Patients requiring vitrectomy for MHs sized > 250 μm.

METHODS

Patients were randomly assigned (1:1) to 1 of the following 2 groups: (1) the control group undergoing standard ILM peeling and (2) the experimental group (flap group) undergoing the temporal inverted ILM flap technique.

MAIN OUTCOME MEASURES

The primary outcome measure was the total DONFL score at 3 months after surgery. Important secondary outcomes were microperimetry results, primary MH closure rate, external limiting membrane (ELM) and ellipsoid zone (EZ) recovery rates, and best-corrected visual acuity (BCVA).

RESULTS

Sixty-five patients were recruited between February 2018 and July 2020; primary outcome data were available for 60 patients. The median DONFL score was 7.0 (3.0-12.5) in the control group and 5.0 (1.5-8.5) in the flap group at 3 months after surgery (P = 0.145). The focal depressions characteristic of the DONFL were limited to the temporal side of the fovea in the flap group, whereas they were found all around the fovea in the control group on spectral-domain OCT images. The MH closure rate (P = 1), EZ and ELM recovery rates (P = 0.252), and BCVA (P = 0.450) were similar between the 2 groups. The 3-month overall median retinal sensitivity (MRS) (P = 0.142) and MRS improvement (P = 0.916) in the control group were comparable with those observed in the flap group. In addition, there was no significant difference between the 2 techniques when considering the temporal area (P = 0.105) or the nasal area (P = 0.468).

CONCLUSIONS

The temporal inverted ILM flap technique reduced the extent of the DONFL by preserving the nasal part of the fovea. However, the overall DONFL score was similar between the 2 techniques. In addition, the MRS and BCVA did not differ from those obtained after complete ILM peeling.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Structural and functional retinal changes in patients with type 2 diabetes without diabetic retinopathy

OBJECTIVE

The characteristics of the early changes in preclinical diabetic retinopathy (DR) are poorly known. This study aimed to analyse the changes in the structure and function of the fundus in diabetic patients without diabetic retinopathy (NDR).

METHODS

This prospective study enrolled patients with type 2 diabetes and healthy controls from April to December 2020. Retinal sensitivity was measured by microperimetry. The peripapillary retinal nerve fibre layer (p-RNFL) thickness, macular retinal thickness, and retinal volume were measured by optical coherence tomography (OCT). The vessel density (VD) and perfusion density (PD) of the peripapillary area, as well as the foveal avascular zone (FAZ) area, FAZ perimeter, and FAZ circularity, were measured by optical coherence tomographic angiography (OCTA).

RESULTS

A total of 71 cases (100 eyes) were enrolled in the study, including 34 cases (51 eyes) in the NDR group and 37 cases (49 eyes) in the control group. The mean retinal sensitivity was lower in the NDR group than in the control group for all sectors (all p < .001). Compared with controls, the NDR group showed thinner p-RNFL in the T sector (76.24 ± 14.29 vs. 85.47 ± 19.66 µm, p = .035). The NDR group had a thinner retina in the N2 sector (304.55 ± 16.07 vs. 312.02 ± 12.30 µm, p = .010). The PD of DCP was lower in the N2 sector in the NDR group (44.92 ± 11.77 vs. 50.27 ± 6.37%, p = .044). The VD was higher in the NDR group in RPCP-S/N/I, and the PD was higher in the RPCP-S/N (all p < .05). The frequencies of perifoveal capillary drop-out, notched or punched out borders of the superficial FAZ, and loss of smooth contour were all higher in the NDR group (all p < .05).

CONCLUSION

The structure (p-RNFL thickness, VD, and PD) and function (retinal sensitivity) display some changes in diabetic patients even if they had not been found to have DR.Key messagesDecreased retinal sensitivity was observed in diabetic patients before the onset of diabetic retinopathy.Compared with the control group, we found the changes in vessel density or perfusion density in a certain area, whether in SCP, DCP, or RPCP in the NDR group.Before the onset of diabetic retinopathy, the structure and function of the retina in diabetic patients had changed.

Seeing invisible light: 2-photon microperimetry to measure visual function

Purpose

The accuracy of conventional visual function tests, which emit visible light, decreases in patients with corneal scars, cataracts, and vitreous hemorrhages. In contrast, infrared (IR) light exhibits greater tissue penetrance than visible light and is less susceptible to optical opacities. We therefore compared conventional visual function tests against infrared 2-phton microperimetry (2PM-IR) in a subject with a brunescent nuclear sclerotic and posterior subcapsular cataract before and after cataract surgery.

Methods

Testing using infrared light microperimetry from a novel device (2PM-IR), visible light microperimetry from a novel device (2PM-Vis), conventional microperimetry, and the cone contrast threshold (CCT) test were performed before and after cataract surgery.

Results

Retinal sensitivity assessed using 2PM-IR, 2PM-Vis, and cMP improved by 3.4 dB, 17.4 dB, and 18 dB, respectively. Cone contrast threshold testing improved for the S-cone, M-cone, and l-cone by 111, 14, and 30.

Conclusions and Importance

2PM-IR, unlike conventional visual function tests, showed minimal variability in retinal sensitivity before and after surgery. Thus, IR visual stimulation may provide a more accurate means of measuring neurosensory retinal function by circumventing optical media opacities, aiding in the diagnosis of early macular disease.

Comparing retinal sensitivities on blue-on-yellow and green-on-yellow perimetry in glaucoma suspects

Purpose

To compare the retinal sensitivities between the blue-on-yellow perimetry (BYP)/short-wavelength automated perimetry (SWAP) and green-on-yellow perimetry (GYP) among patients with and without nuclear sclerosis among glaucoma suspects.

Methods

After ophthalmic examination, patients were subjected to two perimetric tests: BYP and GYP. The visual field (VF) parameters were compared between the two perimeters (p < 0.05 was considered significant).

Results

Fifty-five eyes of 39 patients with a mean age of 60.53 ± 9.70 years were included in the study. Twenty-one eyes had clear lens or pseudophakia. Twenty-six eyes had lower grades of nuclear sclerosis (NO2NC2, NO3NC3) and eight eyes had higher grades of cataract (NO4NC4, NO5NC5). The mean retinal sensitivity (RS) in BYP was 22.08 ± 5.02 (dB) and in GYP was 23.84 ± 5.50 (dB) (p = 0.08). The mean defect in BYP was -2.56 ± 4.40 (dB) and in GYP was -3.24 ± 5.05 (dB), pattern standard deviation (PSD) in BYP was 3.65 ± 1.91 (dB) and in GYP was 3.83 ± 1.99 (dB), and foveal threshold (FT) was 24.20 ± 4.32 (dB) in BYP and 28.10 ± 4.50 (dB) in GYP. The two perimeters showed good agreement by the Bland-Altman plot for all parameters. Fourteen eyes showed perimetric changes suggestive of glaucoma by BYP. In these, GYP had a sensitivity of 92.86% (95% CI of 66.13% to 99.82%) and specificity of 95.12% (95% CI of 83.47% to 99.40%).

Conclusion

BYP and GYP show good agreement. They are comparable in clear media as well as in different grades of nuclear sclerosis. GYP showed good sensitivity and specificity compared to BYP.

[The history and prospects of the microperimetry method in diagnosis of pathologies of the macular region and the optic nerve]

The article discusses the historical development stages of diagnostics of the functional state of the retina and the optic nerve using microperimetry in the Russian Federation and other countries, as well as the features and diagnostic prospects of the microperimetry method in identifying fundus pathologies.

Short-Term Results of Ocriplasmin Versus Prompt Vitrectomy for Macular Hole. Which Performs Better?

In this retrospective study, we compared the anatomical and functional changes in patients with vitreomacular traction associated with macular holes between the following groups: (1) Patients who were treated with a single intravitreal injection of ocriplasmin (the OCRIALONE group); (2) those who failed the ocriplasmin treatment and underwent vitrectomy one month later (the OCRIVIT group); and (3) patients who directly underwent par plana vitrectomy (VITREALONE group). A total of 38 patients, 19 in the OCRIALONE group + OCRIVIT group (seven and 12 patients, respectively) and 19 in the VITREALONE group with focal vitreomacular adhesion associated with macular holes were evaluated with spectral domain optical coherence tomography. Functional examinations included best-corrected visual acuity (BCVA) and microperimetry analysis. Visual function changes were compared between the OCRIALONE group + OCRIVIT group and VITREALONE group up to three months. Furthermore, a subgroup analysis compared the OCRIVIT group and the VITREALONE group. BCVA values and the mean retinal sensitivity showed statistically significant improvement in all groups (p < 0.001). Specifically, the retinal sensitivity values at the end of the follow-up were significantly higher in the OCRIALONE group + OCRIVIT group than in the VITREALONE group. These functional findings were also confirmed when the statistical analysis was conducted between the OCRIVIT group and the VITREALONE group. Although the OCRIALONE group + OCRIVIT group exhibited faster retinal thinning than the VITREALONE group (p = 0.006), the analysis of the OCRIVIT group versus the VITREALONE group did not show any statistically significant difference. The better functional results and similar anatomical findings suggest that ocriplasmin can be used as a first-line treatment, and that prompt pars plana vitrectomy as primary surgery does not provide better outcomes in comparison with pars plana vitrectomy after ocriplasmin injection.