Optical coherence tomography angiography features in patients with idiopathic full-thickness macular hole, before and after surgical treatment

Artificial Intelligence, Digital Imaging, and Robotics Technologies for Surgical Vitreoretinal Diseases

OBJECTIVE

To review recent technological advancement in imaging, surgical visualization, robotics technology, and the use of artificial intelligence in surgical vitreoretinal (VR) diseases.

BACKGROUND

Technological advancements in imaging enhance both preoperative and intraoperative management of surgical VR diseases. Widefield imaging in fundal photography and OCT can improve assessment of peripheral retinal disorders such as retinal detachments, degeneration, and tumors. OCT angiography provides a rapid and noninvasive imaging of the retinal and choroidal vasculature. Surgical visualization has also improved with intraoperative OCT providing a detailed real-time assessment of retinal layers to guide surgical decisions. Heads-up display and head-mounted display utilize 3-dimensional technology to provide surgeons with enhanced visual guidance and improved ergonomics during surgery. Intraocular robotics technology allows for greater surgical precision and is shown to be useful in retinal vein cannulation and subretinal drug delivery. In addition, deep learning techniques leverage on diverse data including widefield retinal photography and OCT for better predictive accuracy in classification, segmentation, and prognostication of many surgical VR diseases.

CONCLUSION

This review article summarized the latest updates in these areas and highlights the importance of continuous innovation and improvement in technology within the field. These advancements have the potential to reshape management of surgical VR diseases in the very near future and to ultimately improve patient care.

FINANCIAL DISCLOSURE(S)

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

Changes in Outcomes of Macular Optical Coherence Tomography Angiography Following Surgery for Optic Disc Pit Maculopathy

PURPOSE

we aimed to report on the optical coherence tomography angiography (OCTA) outcomes of eight patients with optic disc pit maculopathy (ODP-M) who were treated with 23-gauge pars plana vitrectomy (PPV).

METHODS

We examined sixteen eyes of eight patients-eight eyes with ODP-M and eight healthy fellow eyes. Fundus color photography, fundus autofluorescence, fundus fluorescein angiography, optical coherence tomography (OCT), and OCTA were performed. The vascular density, choriocapillaris blood flow (CCBF), and foveal avascular zone (FAZ) were analyzed using OCTA. Moreover, the correlation between the best-corrected visual acuity (BCVA) and macular OCTA parameters was assessed.

RESULTS

Compared with the healthy fellow eyes, the eyes with ODP-M preoperatively were found to have decreased BCVA, superficial capillary plexus (SCP) vascular density (i.e., total, foveal, parafoveal, and perifoveal), deep capillary plexus (DCP) vascular density (i.e., total, parafoveal, and perifoveal), and CCBF but a significantly increased FAZ (p < 0.05). When the eyes with ODP-M were analyzed pre- and postoperatively at month 12 after surgery, the BCVA, SCP vascular density (i.e., perifoveal), and CCBF had significantly increased, and the FAZ had significantly decreased (p < 0.05). When the eyes with ODP-M were compared with the healthy fellow eyes postoperatively at month 12, the BCVA, SCP, and DCP vascular density parameters had increased, along with CCBF, and the FAZ had decreased in eyes with ODP-M, though not to the levels of the healthy fellow eyes (p < 0.05). Moreover, a positive correlation was found between the postoperative BCVA and SCP total vascular density (p < 0.05).

CONCLUSION

The BCVA and macular OCTA parameters improved in eyes with ODP-M at month 12 following surgery. However, the BCVA and OCTA of the eyes operated on did not reach the levels of the healthy fellow eyes, possibly due to impaired choroidal blood flow (CBF) recovery and the presence of a larger FAZ. In summary, OCTA seems to be useful for assessing qualitative and quantitative perioperative microvascular changes.

A cross-sectional study of macular displacement after macular hole surgery with ILM peeling in patients with idiopathic macular hole

PURPOSE

To examine the retinal displacement and change in mean superficial foveal avascular zone (FAZ) after successful closure of macular hole (MH) with vitrectomy with internal limiting membrane peeling (ILM) and gas tamponade.

METHODS

A total of 45 patients with idiopathic MH who underwent 23G pars plana vitrectomy with ILM peeling and tamponade with 20% SF6/14% C3F8 were included. Follow-up visits were performed at 2, 4, and 8 weeks. OCT and OCT-A scans were performed along with detailed ocular examination. Distance between optic disc and an easily identifiable vascular bifurcation nasal and temporal to fovea, FAZ, was noted. Chi-square test (categorical data) and Mann-Whitney U test and t tests for other parameters were performed for statistical analysis.

RESULTS

The mean displacement (µm) of an easily identifiable vascular bifurcation in the nasal quadrant was 96.58 ± 36.55 at 8 weeks and in the temporal quadrant was 273.07 ± 85.51 at 8 weeks. The change was statistically significant in the temporal quadrant (P = <0.001). The mean BCVA changed from a minimum of 0.08 at the preoperative timepoint to a maximum of 0.23 at 8 weeks (P = <0.001). The mean FAZ area (mm²) decreased from a maximum of 0.37 at the preoperative timepoint to a minimum of 0.19 at 8 weeks (p = <0.001).

CONCLUSION

The retina in the temporal quadrant is displaced significantly more than nasal quadrant after successful closure of macular hole. The mean superficial FAZ also decreases suggesting a centripetal movement of the foveal tissue postoperatively.

Retinal microvascular differences after successful macular hole surgery by using the superior and temporal inverted flap technique

PURPOSE

To evaluate the retinal microvascular differences after successful macular hole surgery by using the superior and temporal inverted flap technique.

METHODS

In this retrospective study, patients with idiopathic macular holes with a horizontal diameter of 250-400 μm at the narrowest point, and who have a follow-up of 6 months were included in the study. Group 1 included 14 patients' 14 eyes that have been treated using the superior inverted flap technique. Group 2 included 15 patients' 15 eyes that have been treated using the temporal inverted flap technique. The vessel density (VD) ratios in the superficial capillary plexus (SCP) and the deep capillary plexus (DCP) at the central area and the four parafoveal quadrants were compared between the groups at baseline and postoperative month 6.

RESULTS

The mean baseline BCVA improved significantly in both groups at postoperative month 6 (1.21 to 0.50 and 1.32 to 0.52 logMAR, respectively; P < 0.05). There was no significant difference in mean BCVA between the two groups at postoperative month 6 (P < 0.05). The mean VD in SCP in the center area increased significantly in both groups at month 6 postoperatively (P = 0.011 and 0.020, respectively); however, the mean VD in DCP in the center area did not significantly change in both groups (P = 0.079 and 0.078, respectively). The mean VD ratios in SCP and DCP at the four parafoveal quadrants did not change significantly in both groups at month 6 (P < 0.05 for both).

CONCLUSIONS

Both techniques are safe for retinal microvasculature at postoperative month 6.

Effect of perfluoropropane (C3F8) versus sulfurhexafluoride (SF6) tamponades on the retinal microvasculature after macular hole surgery

PURPOSE

To determine the effects of C3F8 and SF6 gasses by using optical coherence tomography angiography (OCTA) in patients with surgically closed idiopathic full-thickness macular holes (FTMH).

METHODS

A prospective, comparative study, in which 38 eyes of 38 patients with an idiopathic FTMH were studied. Twenty patients were randomized to the C3F8 group and 18 patients to the SF6 group. All patients underwent pars plana vitrectomy, internal limiting membrane peeling with 14 % C3F8 or 20 % SF6 gasses. The superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel densities (VD), foveal avascular zone (FAZ) area in SCP, the choriocapillaris flow area; and subfoveal choroidal thickness (SFCT) were examined at preoperative and postoperative first- and third-month controls using OCTA.

RESULTS

When the changes in the FAZ, SFCT, SCP and DCP VDs were compared, no significant differences were found between the groups (p>0.05 for all). It was determined that the 1-mm radius flow area increases in the C3F8 group at the first and third months after the surgery were significantly higher than in the SF6 group (p<0.05). A significant gain was observed in the BCVA values compared to their preoperative values for both groups; however any differences between the C3F8 and SF6 groups in terms of BCVA were not detected in this study.

CONCLUSION

This is the first report to compare the effects of C3F8 and SF6 gasses on idiopathic FTMH surgery by using OCTA. C3F8 and SF6 gasses may have similar effect on the remodeling process of vascular tissues.

Perifoveal Microvascular Changes following Internal Limiting Membrane Peeling Surgery for Epiretinal Membrane and Macular Hole

INTRODUCTION

The aim of the study was to evaluate perifoveal microvasculature changes following pars plana vitrectomy with internal limiting membrane peeling for the epiretinal membrane (ERM) and macular hole (MH).

METHODS

This retrospective study included 59 eyes from 59 patients. Subjects were divided into two groups: an ERM group (n = 43) and an MH group (n = 16) based on the initial diagnosis. Swept-source optical coherence tomography angiography (SS-OCTA) was performed in the macular area, pre- and postoperatively. Perifoveal microvascular changes were calculated using MATLAB from the 6 × 6 mm SS-OCTA images, excluding the foveal avascular zone. Pre- and postoperative perifoveal vessel densities (pfVDs) were separately analyzed in six sectors (superior, superotemporal, inferotemporal, inferior, inferonasal, and superonasal) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). The baseline characteristics and other clinical factors were compared between the ERM and MH groups.

RESULTS

The postoperative best-corrected visual acuity significantly improved in both groups (p < 0.05). One year after surgery, the pfVD in the SCP of the ERM group significantly decreased in the inferotemporal sector (p = 0.049). The postoperative pfVD in the DCP of the MH group significantly decreased in temporal sectors (p < 0.05). The postoperative mean pfVD in the SCP in the MH group was significantly lower than that in the ERM group (p = 0.003). The presence of a dissociated optic nerve fiber layer (DONFL) was 75% in the MH group and 22% in the ERM group (p = 0.018). The correlation between the pfVD and DONFL was not statistically significant.

CONCLUSION

Postoperative pfVD reduction in the temporal sector, a corresponding area in which DONFL is present after MH surgery, was significantly observed. After vitreoretinal surgery in MH patients, OCTA may serve as a useful tool for monitoring perifoveal microvascular changes, especially in temporal sectors.

The effect of ethnicity on anatomic success following macular hole surgery: a multicentre cohort study

PURPOSE

The purpose is to assess the effect of ethnicity on surgical macular hole closure.

METHODS

A retrospective cohort study was undertaken in five UK National Health Service Hospitals. We included all patients with known ethnicity undergoing vitrectomy, internal limiting membrane peel, and gas/oil tamponade for all stages of primary full-thickness macular hole (FTMH). The primary outcome was anatomic success, defined as FTMH closure with one operation. The secondary outcome was mean change in best-corrected visual acuity (BCVA) comparing baseline with final review.

RESULTS

Of 334 operations, the ethnicity profile comprised 78.7% White patients, 11.7% Black patients, 8.1% Asian patients, and 1.5% in mixed/other ethnicities. Mean age was 69.7 years with 68.5% females. Overall, 280 (83.8%) had anatomic success. Anatomic failure occurred in 38.5% of Black patients versus 12.6% of White patients (relative risk: 1.788; 95% CI: 1.012 to 3.159; P = 0.045). Overall, baseline logarithm of the minimum angle of resolution BCVA improved by 0.34, from 0.95 (95% CI: 0.894 to 1.008) to 0.62 (95% CI: 0.556 to 0.676). Mean BCVA improved by 0.35 in White patients, 0.37 in Black patients, 0.23 in Asian patients, and 0.38 in mixed/other ethnicity (P = 0.689). Greater FTMH minimum linear diameter was associated with an increased risk of anatomic failure (relative risk: 1.004; 95% CI: 1.002 to 1.005; P < 0.0001), whereas better pre-operative BCVA (F [1,19] = 162.90; P < 0.0001) and anatomic success (F [1,19] = 97.69; P < 0.0001) were associated with greater BCVA improvement. Socio-economic status did not significantly influence anatomic success or BCVA change.

CONCLUSIONS

Black ethnicity is associated with an approximately twofold greater risk of failed FTMH surgery. The reasons for this difference warrant further study.

Changes in vascular density in the macula after pars plana vitrectomy for idiopathic macular hole with macular peeling and one type of flap

BACKGROUND AND AIMS

The aim of this study was to evaluate changes in vascular density in the macula after pars plana vitrectomy for idiopathic macular hole (IMD) with macular peeling and flap.

METHODS

A prospective study of 35 eyes in 34 patients who had undergone standard surgery. Evaluated parameters were best-corrected visual acuity (BCVA), intraocular pressure (IOP), central macular thickness (CRT), macular volume (TMV) and vascular density of the superficial and deep capillary plexus. The follow-up period was one year.

RESULTS

We divided the total group into two: temporal and circular flap and total group. We compared the values after surgery with the preoperative values. In the total group, BCVA increased from 48.38 to 71.44 letters (P≤0.05). IOP changed from 15.24 to 14.76 mmHg (P>0.05). CRT decreased from 432.27 to 323.64 µm (P≤0.05). TMV changed from 0.26 to 0.25 mm3 (P>0.05). The vascular density of the superficial plexus decreased from 32 to 28% (P≤0.05). The intercapillary space of the superficial plexus increased from 68 to 72% (P≤0.05). The vascular density of the deep plexus increased from 17 to 23%. The intercapillary space of the deep vascular plexus decreased from 83 to 77%. Changes in vascular density and intercapillary space of the deep plexus were statistically significant for certain months after operations (P≤0.05). There were no significant differences between subgroups.

CONCLUSION

The superficial plexus vascular density is almost the same in the temporal flap and in the foveal-sparing flap is decreased, and the deep plexus vascular density increased statistically significantly during the follow-up period after surgery.

Optical Coherence Tomography Angiography in Macular Holes Autologous Retinal Transplant

In this paper, we compare the post-operative macular microvascular parameters (vascular density and foveal avascular zone) in eyes with refractory macular hole (MH) that underwent pars plana vitrectomy and autologous retinal transplant (ART) with the fellow unoperated eye. We conducted a retrospective case control study of six consecutive patients who underwent pars plana vitrectomy and ART with at least six months of post-operative follow-up. Pre-operatively, all eyes underwent SD-OCT (Spectral Domain Optical Coherence Tomography) examination. Post-operative OCT-A analyses included vascular density (VD) and the foveal avascular zone (FAZ) area. Six patients with a mean age of 63.7 ± 14.3 years were included. The mean follow-up was 24 months (range 6–30 months). The pre-operative BCVA (best-corrected visual acuity) was 0.99 ± 0.46 logMAR and 1.02 ± 0.23 logMAR at the last post-operative visit (p = 1.00). The mean MH diameter was 966 ± 620 µm. VD in the MH group was 28.1 ± 7.3% compared to 20.2 ± 2.9% in the fellow eyes group (p < 0.05). The mean post-operative FAZ area in the MH group was 109.8 ± 114.6 mm2 compared to 41.5 ± 10.4 mm2 in the control group (p < 0.05). In all six eyes, MH closure was obtained. The post-operative visual acuity did not improve after ART. Eyes with a closed MH showed a bigger FAZ with a higher VD compared to the fellow healthy eye.

Non-Invasive Retinal Imaging Modalities for the Identification of Prognostic Factors in Vitreoretinal Surgery for Full-Thickness Macular Holes

In this review, we will focus on different non-invasive retinal imaging techniques that can be used to evaluate morphological and functional features in full-thickness macular holes with a prognostic purpose. Technological innovations and developments in recent years have increased the knowledge of vitreoretinal interface pathologies by identifying potential biomarkers useful for surgical outcomes prediction. Despite a successful surgery of full-thickness macular holes, the visual outcomes are often puzzling, so the study and the identification of prognostic factors is a current topic of interest. Our review aims to provide an overview of the current knowledge on prognostic biomarkers identified in full-thickness macular holes by means of different retinal imaging tools, such as optical coherence tomography, optical coherence tomography angiography, microperimetry, fundus autofluorescence, and adaptive optics.

Functional features in patients with idiopathic macular hole treatment via OCT angiography

To evaluate the optical coherence tomography (OCT) angiography features in patients with idiopathic macular hole (IMH) before and after vitrectomy. This prospective study included 25 patients diagnosed with IMH in Shanxi eye hospital from August 2019 to December 2021. The study was divided into 3 groups: IMH eyes, fellow eyes and normal eyes. All unilateral IMH eyes underwent vitrectomy. There were significant differences in superficial retinal blood flow density (SRBFD, P < .001) and choroidal blood flow density (CBFD) between IMH and healthy control eyes before operation (P < .05). There was significant difference in SRBFD between fellow eyes and normal eyes (P = .038). The changes of SRBFD and CBFD in IMH eyes before and after operation were statistically significant (P < .05). The CBFD at 6 months after operation is negatively correlated with LogMAR visual acuity, and the CBFD of the fellow eye is also negatively correlated with LogMAR visual acuity. The SRBFD and CBFD had no correlation with the diameter of macular hole before and after operation. SRBFD and CBFD increased after vitrectomy, indicating that the blood supply of retina and choroid were partially restored after vitrectomy. There was no correlation between SRBFD, CBFD and hole diameter, but there was correlation between choroidal blood flow and LogMAR visual acuity.

Treatment of recurrent high myopic macular hole associated with retinal detachment using a human amniotic membrane

PURPOSE

To determine the efficacy of using a human amniotic membrane to close macular hole retinal detachment in highly myopic eyes.

STUDY DESIGN

Prospective, consecutive, nonrandomized interventional study.

METHODS

We included 19 high myopic eyes from 19 patients affected by macular hole retinal detachment who had already undergone vitrectomy with internal limiting membrane peeling. The patients underwent vitrectomy with amniotic membrane transplant.

RESULTS

Primary success was achieved after 3 months in 89.5% (17 of 19 eyes) and final macular hole closure was obtained in 94.7% (18 of 19 eyes) of the patients. The final retinal reattachment rate was 100%. The final 12-month mean BCVA improved from 20/2000 (2 logMAR) to 20/250 (1.1 logMAR). OCT-angiography revealed a high correlation between the superficial and deep capillary plexus and the final BCVA.

CONCLUSION

Human amniotic membrane patches can effectively repair macular hole retinal detachment in high myopic eyes in terms of anatomic results and BCVA recovery.

Swept-Source OCT Angiography Features in Patients after Macular Hole Surgery

This study aimed to compare findings of optical coherence tomography (OCT) angiography (OCTA) between eyes with nearly recovered and partially recovered outer retina after full-thickness macular hole (FTMH) surgery and to identify OCTA findings associated with visual acuity. We retrospectively reviewed 30 patients who underwent surgery for idiopathic FTMH. Swept-source OCT (SS-OCT) and OCTA were performed preoperatively and at three and six months postoperatively. Subgroups were divided according to the integrity of the external limiting membranes and ellipsoid zones postoperatively. Correlations of best-corrected visual acuity six months postoperatively with SS-OCT and OCTA measurements were analyzed. There was no difference in preoperative retinal or choroidal vascular index on OCTA between the nearly and partially recovered groups. Six months postoperatively, the choriocapillaris flow-void area was significantly higher in the partially recovered group than in the fellow eye. The nearly recovered group showed better choroidal vascular flow, and vision at six months postoperatively correlated with the ratio of the operated eye’s choriocapillaris flow-void area to the fellow eye. Sufficient choriocapillaris flow on OCTA is associated with better outer retinal recovery and visual outcomes after macular hole surgery.

Makuler hol cerrahisinin anatomik ve fonksiyonel başarısını etkileyen parametreler

Aim: To evaluate the effect of preoperative Spectral Domain Optical Coherence Tomography (SD-OCT) parameters on macular hole surgery (MHS) and their predictive value for postoperative best corrected visual acuity (BCVA). Materials and Methods: This retrospective study included 30 eyes of 30 patients with macular hole (MH). All patients underwent pars plana 23-gauge vitrectomy. A detailed macular analysis including MH minimum diameter (MD), base diameter (BD), opening diameter (OD), height, nasal arm (NA), temporal arm (TA), macular hole index (MHI), diameter hole index (DHI), tractional hole index (THI), hole form factor (HHF), macular hole area (MHA), and macular hole volume (MHV) were performed preoperatively. Presence of inner segment–outer segment (IS/OS) line, external limiting membrane (ELM), and cyst was noted postoperatively. Relationships between these parameters and postoperative BCVA were evaluated. Results: The study group comprised 25 (83.3%) women. Mean pre and postoperative BCVA values were 0.924±0.320 and 0.487±0.287 logMAR, respectively. BCVA improved significantly after MHS (p

Comparison of Idiopathic Macular Hole Interventions Using Frequency Domain Optical Coherence Tomography and Optical Coherence Tomography Angiography

Objective

We aimed to determine the efficacy of different idiopathic macular hole treatment methods to improve recovery time and patient outcomes using Frequency Domain Optical Coherence Tomography (SD-OCT) and Optical Coherence Tomography Angiography (OCTA).

Methods

This retrospective study included patients with idiopathic macular hole who were admitted to our hospital between 1st January 2019 and 31st October 2021. The control group was treated with internal limiting membrane tamponade, and the study group was treated with clamshell therapy. Treatment conditions (internal limiting membrane treatment duration and hole closure rate), best corrected visual acuity (BCVA) before and after surgery, OCTA measurements, and SD-OCT were assessed. The retinal nerve fiber layer (RNFL), retinal ganglion cell layer (GCL), and retinal pigment epithelium (RPE) thicknesses were also analyzed.

Results

The treatment time and hole closure rate of the internal limiting membrane in the study group were higher than those in the control group. The curative effect of the study group was better than that of the control group. The postoperative DCP blood vessel density in both groups was higher than that before operation, and the study group was higher than the control group. The FAZ area and circumference were lower than those before surgery, and the study group was lower than the control group. At 3 months after operation, the thickness of DIOA, nasal temporal RNFL, and GCL were decreased in both groups, and the observed values in the study group were lower than those in the control group. At 3-month follow-up, there was no significant difference in RPE thickness between the two groups.

Conclusion

Flip and cover therapy is the most effective treatment. SD-OCT and OCTA provide an objective basis for clinical intervention by comparing the effects of different procedures on the retinal condition of patients.

Choroidal vascularity index changes with phacovitrectomy for vitreoretinal interface disorders

Purpose

Vitreomacular interface disorders have long been argued to change choroidal structure. The aim of this study was to determine the choroidal vascularity index (CVI) changes following internal limiting membrane peeling for epiretinal membrane (ERM) and full thickness macular hole (FTMH).

Methods

Fifty-nine patients with unilateral ERM and 56 with unilateral FTMH were included in the study. Axial length, pre- and post-surgery intraocular pressure, baseline and post-phacovitrectomy CVI were calculated and compared with the normal fellow eyes. To compare the baseline and the final measurements, Wilcoxon test was used. Mann-Whitney U test was used for independent data comparisons. Median and standard deviations were compared.

Results

Axial length, pre- and post-surgery intraocular pressure differences were insignificant between study and fellow eyes within all groups. CVI were significantly lower in post-vitrectomy study eyes of all groups compared with pre-surgery (P < 0.001). There were no significant changes before and after the surgeries in fellow eyes. Baseline CVI of ERM study eyes (median 65.90%) and FTHM study eyes (median 65.59%) did not differ significantly between groups (U = 1336, P = 0.07, r = 0.16).

Conclusion

There are conflicting results of vitreoretinal interface disorders CVI in the literature. In this study, both FTMH and ERM eyes showed reduced CVI postoperatively compared with the baseline. Preoperatively, there were no difference between study eyes and the fellow eyes.

Vitrectomy combined with lens capsule flap transplantation in the treatment of high myopia macular hole retinal detachment: study protocol for a prospective randomised controlled trial

INTRODUCTION

Vitrectomy combined with internal limiting membrane (ILM) peeling, flap or tamponade is widely used in the treatment of macular diseases, such as macular hole (MH) and high myopia macular hole retinal detachment (HMMHRD). However, movement of the ILM to a suitable position to prevent displacement is a difficult operation. Improving visual function after surgery remains controversial. Compared with ILM, the thicker and more flexible lens capsule is easy to obtain and operate. Previous studies have confirmed the effectiveness of lens capsule flap in the treatment of MH. This study aims to evaluate the efficacy and safety of vitrectomy combined with lens capsule flap transplantation in the treatment of HMMHRD.

METHODS AND ANALYSIS

This single-centre, single-blind, prospective, randomised clinical trial will include 54 patients with HMMHRD who will first undergo phacoemulsification and intraocular lens implantation and then vitrectomy combined with lens capsule flap transplantation (experimental group) or ILM tamponade (control group). Study participants will be randomly allocated in a 1:1 ratio to experimental and control groups. Follow-up will be conducted 1, 3 and 7 days and 1, 3 and 6 months after surgery in both groups. Necessary examinations will be performed at each follow-up visit. Measurement outcomes include postoperative situation of macular hole closure, best-corrected visual acuity, macular retinal function and macular retinal sensitivity. The primary outcome is type I closure rate of MH 6 months after operation. Intergroup comparisons of the proportions of patients with type I closure of MH will be performed with Fisher's exact test.

ETHICS AND DISSEMINATION

Full ethics approval for this study was obtained from the Ethics Committee of Shanghai General Hospital, Shanghai Jiaotong University, Shanghai, China. The outcomes of the trial will be disseminated through peer-reviewed journals and at scientific conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2200057836.

Morphological and Functional Features in Patients with Idiopathic Macular Hole Treatment

Purpose

To evaluate the multifocal electroretinogram (mfERG) and optical coherence tomography (OCT) angiography features in patients with idiopathic macular hole (IMH) before and after vitrectomy.

Patients and Methods

This prospective study was conducted at Shanxi Eye Hospital from January 2019 to December 2021. Twenty-five eyes of 25 patients with unilateral IMH, the unaffected fellow eyes, and 30 eyes of healthy patients were investigated. All unilateral IMH eyes underwent vitrectomy.

Results

The IMH eyes had significantly delayed latency (rings 2-5) of mfERG compared with the healthy control eyes, and the amplitude density of all rings of mfERG was reduced (P < 0.05). When comparing the mfERG components before surgery and at the follow-up, the amplitude density of IMH eyes (ring 1, 3, 4 and 5) was increased significantly (P < 0.05). The delayed implicit times of the second and fifth ring were significantly shortened compared with those of preoperative eyes (P < 0.05). The mean delayed implicit time of mfERG in six months after surgery was negatively correlated with visual acuity (r = -0.890, P = 0.043). Significant differences of superficial retinal blood flow density (SRBFD, P < 0.001) and choroidal blood flow density (CBFD) (P < 0.05) got via OCTA were found between IMH before surgery and healthy control eyes. SRBFD of the fellow eyes were significantly different with the healthy control eyes (P = 0.038). Statistically significance of SRBFD and CBFD changes in IMH eyes were found before and after surgery (P < 0.05).

Conclusion

IMH eyes had a decreased amplitude density and a delayed implicit time in some regions. Additionally, SRBFD and CBFD were both increased after vitrectomy, which suggests that the blood supply of the retina and choroid is partially restored after vitrectomy.

The effect of phacoemulsification performed with vitrectomy on choroidal vascularity index in eyes with vitreomacular diseases

This study evaluated the effects of cataract surgery combined with pars plana vitrectomy (ppV) on choroidal vascularity index (CVI) in eyes with epiretinal membrane (ERM) and full thickness macular hole (FTMH). Medical records of 132 eyes with ERM or FTMH were retrospectively reviewed and classified into a ppV group and a ppV combined with cataract surgery group (phaco + ppV group). The CVI were measured at baseline, 1, 3 and 6 months after the surgery, using the selected swept-source (SS) optical coherence tomography (OCT) scan passing through the central fovea, which was then segmented into luminal and stromal area by image binarization. The mean CVI of phaco + ppV group were 61.25 ± 1.97%, 61.66 ± 1.81%, and 62.30 ± 1.92% at baseline, 1 and 3 months, respectively (p < 0.001). The mean CVI of ppV group were 62.69 ± 1.92%, 62.03 ± 1.51%, and 61.45 ± 1.71% at baseline, 1 and 3 months, respectively (p < 0.001). The final CVI were measured at 6 months and compared with the baseline CVI. The mean CVI of phaco + ppV group were 61.21 ± 1.99% at baseline and 60.68 ± 2.02% at 6 months (p < 0.001). The mean CVI of ppV group were 62.93 ± 1.70% at baseline and 61.77 ± 1.74% at 6 months (p < 0.001). Vitrectomy significantly decreases CVI in vitreomacular diseases possibly due to the removal of vitreomacular traction or postoperative oxygenation change in the eye. On the contrary, combined surgery of vitrectomy and cataract surgery significantly increases CVI in the early stage of postoperative period, which suggests choroidal vascular dilatation or congestion due to postoperative inflammation. Although the CVI were measured lower than the baseline in the end, more thorough inflammation control may be essential after combined surgery.

Macular microvasculature differences in patients with macular hole after vitrectomy with internal limiting membrane removal or single-layered temporal inverted flap technique

PURPOSE

To compare the macular microvasculature differences in cases with idiopathic macular hole (MH) after vitrectomy when using internal limiting membrane (ILM) removal or temporal inverted ILM flap technique (IFT).

METHOD

A total of 34 patients were included, of whom 20 were treated vitrectomy with ILM removal (group 1), and 14 were treated with IFT (group 2). The OCTA (RTVue; Optovue, Fremont, CA) parameters, including foveal avascular zone (FAZ), vessel density (VD) ratios in superficial capillary plexus (SCP), and deep capillary plexus (DCP) were evaluated at baseline and 6 months follow-up. The VD measurements in DCP and inner retinal thickness (IRT) in temporal and nasal sectors were compared in subanalyses.

RESULTS

There was no significant difference in means of post-operative BCVA and FAZ between the two groups (p = 0.943, p = 0.760). The mean VDs of the DCP was significantly decreased at 6 months postoperatively in both groups (p < 0.001, p < 0.001). The mean post-operative temporal VDs of DCP were similar in the two groups, but the mean post-operative nasal VDs of the DCP was lower in group 1 than in group 2 (p = 0.005 and p = 0.03 for parafovea and perifovea, respectively). The mean temporal IRTs were similar in the two groups, but paranasal and perinasal IRTs were significantly thinner in group 1 than in group 2 (p < 0.001, p < 0.001). The mean post-operative VDs of parafoveal and perifoveal temporal and nasal quadrants in DCP significantly and positively correlated with the IRTs.

CONCLUSION

Single-layered temporal IFT causes fewer VD changes when compared to complete ILM removal, especially in the DCP.

Retinal capillary involvement in early post-COVID-19 patients: a healthy controlled study

BACKGROUND

Systemic vascular involvement in COVID-19 has been identified in several patients: not only endothelial derangement and increased permeability are reported to be early hallmarks of organ damage in patients with COVID-19 but are also the most important cause of worsening of clinical conditions in severe cases of SARS-CoV-2 infection. There are several reasons to hypothesize that the eye, and the retina in particular, could be a target of organ damage in SARS-CoV-2 infection.

METHODS

This cohort observational study analyzes OCT angiography and structural OCT of 70 post-COVID-19 patients evaluated at 1-month hospital discharge and 22 healthy control subjects. Primary outcomes were macular vessel density (VD) and vessel perfusion (VP); structural OCT features were evaluated as secondary outcomes. In addition, patients and healthy volunteers were evaluated for best corrected visual acuity, slit lamp photograph, and fundus photo image.

RESULTS

VD and VP in 3 × 3 and 6 × 6 mm scans for SCP and DCP showed no significant differences between the groups. Similarly, CMT and GCL did not reveal significant differences between post-COVID-19 and healthy patients. Nine patients (12.9%) featured retinal cotton wool spots and 10 patients had vitreous fibrillary degeneration. The prevalence of epiretinal membrane and macular hole was similar in the two groups. One case of extra papillary focal retinal hemorrhage was reported in the post-COVID-19 group.

CONCLUSIONS

Macula and perimacular vessel density and perfusion resulted unaltered in mild post-COVID-19 patients at 1-month hospital discharge, suggesting no or minimal retinal vascular involvement by SARS-CoV-2.

Choriocapillaris: Fundamentals and advancements

The choriocapillaris is the innermost structure of the choroid that directly nourishes the retinal pigment epithelium and photoreceptors. This article provides an overview of its hemovasculogenesis development to achieve its final architecture as a lobular vasculature, and also summarizes the current histological and molecular knowledge about choriocapillaris and its dysfunction. After describing the existing state-of-the-art tools to image the choriocapillaris, we report the findings in the choriocapillaris encountered in the most frequent retinochoroidal diseases including vascular diseases, inflammatory diseases, myopia, pachychoroid disease spectrum disorders, and glaucoma. The final section focuses on the development of imaging technology to optimize visualization of the choriocapillaris as well as current treatments of retinochoroidal disorders that specifically target the choriocapillaris. We conclude the article with pertinent unanswered questions and future directions in research for the choriocapillaris.

Changes in choroidal blood flow in patients with macular hole after surgery

INTRODUCTION

A macular hole (MH) is a defect that occurs in the retina and involves all layers. In this study, we aimed to investigate the preoperative and postoperative choriocapillaris blood flow (CBF) changes in patients with MH and the role of CBF in the pathogenesis of the disease using optical coherence tomography angiography (OCTA).

MATERIAL METHOD

This is a retrospective study examining eyes with MH. The study included 25 operated eyes of 25 patients and contralateral eyes of 18 patients. CBF and subfoveal choroidal thickness were examined using the OCTA images of the patients before surgery and at the first, third and sixth months after surgery.

RESULTS

The mean CBF value of the patients was 1.57±0.20 mm² preoperatively, 1.94±0.13 mm² at the postoperative first month, 1.98±0.12 mm² at the third month, and 2.00±0.10 mm² at the sixth month. The increases in the CBF values between the preoperative period and the postoperative measurements were statistically significant (p<0.0001 for all). In the preoperative period, the CBF value of the contralateral eyes was 2.07±0.10 mm². The preoperative CBF value of the contralateral eyes was higher compared to that of the eyes with MH (p<0.0001). There was no significant difference between the preoperative CBF value of the contralateral eyes and the postoperative sixth-month value of the eyes with MH (p = 0.065).

CONCLUSION

The preoperative and postoperative third-month CBF values of the eyes with MH were found to be lower than those of the contralateral eyes, but there was no difference between the postoperative sixth-month CBF value of the eyes with MH and the preoperative CBF value of the contralateral eyes. We consider that the eyes with MH achieve similar CBF values to the contralateral eyes in an average of six months after successful surgery.

Early Vascular and Functional Changes after Vitreoretinal Surgery: A Comparison between the Macular Hole and Epiretinal Membrane

(1) Background: The aim of this observational comparative study was to investigate early retinal vascular and functional changes in patients undergoing vitreoretinal surgery for idiopathic epiretinal membrane (iERM) or macular hole (MH) using a widefield swept-source optical coherence tomography angiography (WSS-OCTA). (2) Methods: Forty one diseased eyes were enrolled in the study. Twenty three eyes with iERM diagnosis (ERM group) underwent 25-gauge vitrectomy with inner limiting membrane (ILM) and MER peeling, while eighteen eyes with MH (MH group) underwent 25-gauge vitrectomy with inverted flap technique. Functional and anatomical/perfusion parameters were evaluated pre- and postoperatively in all eyes by means of WSS-OCTA system, microperimetry (MP3), best corrected visual acuity assessment, central macular thickness (CMT) and MH diameter calculation. For each eye, 12 × 12 mm OCTA volume scans were acquired by a retinal specialist and a semi-automated algorithm was used for a quantitative vessel analysis of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC). In detail, perfusion density (PD) of the SCP, DCP and CC was evaluated in four circles (one central in the macular area of 5 mm diameter; three midperiphery circles (temporal, superior and inferior) of 3 mm). In addition, the vessel length density (VLD) of the SCP and DCP for the same circles was quantified. (3) Results: In the MH group, PD of the SCP significantly increased in the macular area (p = 0.018) and in the superior ring (p = 0.016); PD of the DCP significantly increased in the macular area (p = 0.015) and in the superior and inferior ring (p = 0.016) 3 months after surgery. In the ERM group, PD of the SCP and DCP significantly increased in the macular area and superior ring, respectively (p = 0.001; p = 0.032), 3 months after surgery. During follow-up there was a significant improvement in terms of functional (Best corrected visual acuity, p = 0.007 and p = 0.029; microperimetry ((MP3) 10°, p = 0.003 and p = 0.004; MP3 2°, p = 0.028 and p = 0.003 in MH group and ERM group respectively) and anatomical parameters (CMT, p = 0.049 in ERM group; hole complete closure in MH group). (4) Conclusions: After vitreoretinal surgery, early retinal vascular and functional changes can be promptly observed and quantified to monitor and potentially predict surgery outcomes. Widefield OCTA devices allow for a detailed microvasculature analysis of retina and choriocapillaris in the macular area and in the periphery, showing a different behaviour of retinal sectors in two distinct vitreoretinal disorders.

Choroidal blood perfusion as a potential "rapid predictive index" for myopia development and progression

Myopia is the leading cause of visual impairment worldwide. The lack of a "rapid predictive index" for myopia development and progression hinders the clinic management and prevention of myopia. This article reviews the studies describing changes that occur in the choroid during myopia development and proposes that it is possible to detect myopia development at an earlier stage than is currently possible in a clinical setting using choroidal blood perfusion as a "rapid predictive index" of myopia.

OCT-A in the Management of Vitreoretinal Diseases and Surgery

ABSTRACT

Optical coherence tomography angiography is a relatively new noninvasive technique that is changing our approach in the management of several retinal diseases such as neovascular age-related macular degeneration, occlusive retinal diseases, or diabetic retinopathy, but it could also be useful in nonprimary vascular retinal pathologies such as vitreoretinal interface surgical disorders.In idiopathic vitreoretinal interface disorders and surgical retinal diseases, the study of vascular involvement, not commonly assessed by invasive methods, could be useful to reveal specific vascular abnormalities. Such information may be useful for a more detailed phenotyping of each clinical picture before and after surgical treatment, providing potential new prognostic biomarkers.The review discusses the current and potential utility of optical coherence tomography angiography to study vitreoretinal pathologies of surgical interest.

Secondary Vitrectomy with Internal Limiting Membrane Plug due to Persistent Full-Thickness Macular Hole OCT-Angiography and Microperimetry Features: Case Series

Purpose

To study the features in OCT-angiography and microperimetry in eyes with persistent full-thickness macular hole (FTMH) closed with the secondary plana vitrectomy (PPV) with autologous internal limiting membrane (ILM) plug.

Methods

Secondary PPV was performed with closing the persistent FTMH with ILM plug, C₃F₈ tamponade, and face-down positioning. Four patients were followed for 6 months with best corrected visual acuity (BCVA) measurement, SD-OCT and OCT-A, and microperimetry. The results were compared with the fellow eye; in two patients, it was the healthy eye, and in two remaining eyes, successfully closed FTMH after primary PPV.

Results

ILM flap was integrated in all cases with V-shape of closure, and atrophy was found in one case, with the largest diameter of FTMH. BCVA improved in two cases and remained the same in two cases. In OCT-A, the area of foveal avascular zone (FAZ) was larger, and foveal vessel density (FVDS) was smaller in eyes after secondary PPV in comparison to fellow eyes. In microperimetry, retinal sensitivity was lower in eyes after secondary PPV, and eccentric fixation was found in 2 of 4 patients.

Conclusion

Although the anatomical results of repeated surgeries of FTMH with ILM plug are favorable, visual function results may be limited. Secondary closure of FTMH with ILM plug may lead to atrophy, changes in the macular vasculature, and eccentric fixation. The trial is registered with NCT03701542.

Optical coherence tomography angiography using the black-and-white pixel binarization histogram software: a new technique for evaluating healing of macular holes in two surgical techniques

Background

Many factors can influence the functional outcomes of macular hole surgery and some studies have tried to describe anatomical features that could predict successful treatment. The purpose of this study is to describe a new technique for evaluating the healing of macular holes after two surgical techniques using a black-and-white pixel binarization histogram software by optical coherence tomography angiography and its potential functional implications.

Methods

This was a retrospective, observational case series of patients who presented with idiopathic full-thickness macular holes and underwent vitreoretinal surgery for successful macular hole closure using the internal limiting membrane peeling technique or the inverted peeling technique or the free internal limiting membrane flap technique. Optical coherence tomography angiography 3.0 × 3.0-mm scans were obtained postoperatively. The outer retina layer was analyzed separately; three different analyses were performed within a 3.0-mm-diameter area central circle, a 1.5-mm-diameter area, and a 0.5-mm-diameter area from the foveal center. The outer retinal layer images were evaluated by counting the number of black and white pixels. The inclusion criteria were patients with idiopathic macular holes who underwent ophthalmologic examinations and swept-source optical coherence tomography 1 week and 1 and 6 months postoperatively. The exclusion criteria were a traumatic macular hole or a history of eye trauma and a diagnosis of glaucoma or any other chronic ocular disease. The Mann–Whitney test was used to determine significance; P < 0.05 was considered significant.

Results

Ten eyes of 10 patients who underwent vitreoretinal surgery to treat a macular hole either with the conventional peeling technique (n = 5) or the inverted/free internal limiting membrane flap technique (n = 5) were included. In the peeling group, the percentage of white pixels ranged from 7.22% to 18.40% in the 0.5 × 0.5-millimeter area in the macular center; the mean postoperative logarithm of the minimum angle of resolution best-corrected visual acuity was 0.3 ± 0.2. In the inverted flap group, the percentage of white pixels ranged from 3.65% to 8.93% in the 0.5 × 0.5-millimeter area in the macular center; the mean logarithm of the minimum angle of resolution best-corrected visual acuity was 0.9 ± 0.4.

Conclusions

A simple method of optical coherence tomography angiography imaging analysis of the outer retina using a binarization technique of the black and white pixels was created and may have functional implications during the analysis of the healing process after macular hole surgery. We hypothesized that higher numbers of white pixels correspond to viable cellularity and better prognoses postoperatively.

Morpho-Functional Evaluation of Full-Thickness Macular Holes by the Integration of Optical Coherence Tomography Angiography and Microperimetry

(1) Objective: To use optical coherence tomography angiography (OCTA) and microperimetry (MP) to evaluate the correlation between retinal structure and function in patients with idiopathic, full-thickness macular holes (FTMHs) (2) Methods: This prospective, observational study included 11 eyes of 10 patients with FTMHs evaluated before surgery using OCTA and MP. MP sensitivity maps were superimposed and registered on slabs corresponding to superficial capillary plexus (SCP) and deep capillary plexus (DCP) on OCTA, and on the outer plexiform layer (OPL) and the Henle fiber layer (HFL) complex in en face OCT. On these maps, mean retinal sensitivity was calculated at 2° and 4°, all centered on the FTMH. Cystic cavity extension was assessed on the slab corresponding to the OPL + HFL complex in en face OCT and DCP in OCTA using the Image J software (Version 1.49v; National Institutes of Health, Bethesda, MD, USA); (3) Results: Absolute scotomas were observed corresponding to the FTMH. Additionally, rings of relative scotoma in the perilesional area were detected and correlated to the cystic spaces on en face OCT and OCTA. There was a significant correlation between reduced retinal sensitivity at 2° and 4° diameters around the FTMH and the extension of cystic areas (p < 0.01). There was a significant correlation between the extension of cystic cavities and BCVA (p < 0.01). (4) Conclusions: Morpho-functional analysis of FTMH using OCTA and MP, and the correlation between vascular abnormalities and impaired retinal sensitivity, may provide new, useful information. This integrated evaluation of FTMH may be useful to determine the function–structure correlation before and after vitreoretinal surgery, in order to gain a better understanding of the functional consequences induced by the morphological alterations, assessing outcomes in a more objective way, and potentially adding new surgical prognostic factors.

Incomplete fluid-air exchange technique for idiopathic macular hole surgery

AIM

To explore an improved procedure involving incomplete fluid-air exchange for idiopathic macular hole (IMH), and the closure rate, visual function, and the visual field of macular holes (MHs) were evaluated.

METHODS

This prospective randomized controlled study, included 40 eyes of 40 patients with IMH who were treated with pars plana vitrectomy and peeling of the internal limiting membrane. They were grouped by random digital table. Twenty-one eyes underwent incomplete fluid-air exchange (IFA) and 19 eyes underwent traditional complete fluid-air exchange (CFA) as the control group. Outcomes included best-corrected visual acuity (BCVA), intraocular pressure, and optical coherence tomography, light adaptive electroretinography, and visual field evaluations.

RESULTS

All MHs <400 µm were successfully closed. BCVAs before and 6mo after surgery were 0.82±0.41 logMAR and 0.28±0.17 logMAR in IFA group and 0.86±0.34 logMAR and 0.34±0.23 logMAR in CFA group, respectively. The electroretinogram analysis of patients in IFA group revealed increases in b-wave amplitudes at 1, 3, and 6mo after surgery. Additionally, patients in IFA group showed an amplitude increase of 28.6% from baseline at 6mo (P<0.05), while no obvious improvements were noted in CFA group. Although there were no statistically significant improvements in either group, the IFA group showed a slight increase in mean sensitivity (P>0.05).

CONCLUSION

IFA is a reliable method that offers comparable closure rate to CFA and facilitates improvements in visual function.