Vascular Features of Full-Thickness Macular Hole by OCT Angiography

[Multimodal topographically oriented approach to the study of full-thickness macular holes]

PURPOSE

This article studies the relationship between structural changes according to the findings of optical coherence tomography (OCT) and OCT angiography (OCTA), microperimetry (MP), multifocal electroretinography (mfERG) parameters in topographically corresponding areas of the macular region in idiopathic full-thickness macular holes (FTMH).

MATERIAL AND METHODS

OCT, OCTA, MP and mfERG were performed in 14 eyes with FTMH stages I-IV according to Gass. In 13 points at a distance of 0-2.5°, 2.5-5.0°, and 5.0-10.0° from the fixation point, the light sensitivity (LS), amplitude and latency of the P1 component were compared with the size of the hole, the area of cystic changes (CC) at the level of the inner nuclear layer (INL) and the outer plexiform layer and Henle fiber layer complex (OPL+HFL), vessel density in the superficial and deep capillary plexus (SCP and DCP).

RESULTS

LS and P1 component amplitude were significantly reduced at a distance of up to 5.0° from the fixation point. LS correlates with the apical and basal diameter of the hole (R> -0.53), the area of CC in the INL (R> -0.62) and the OPL+HFL complex (R> -0.55), the density of vessels in the SCP at a distance of up to 2.5° from the fixation point (R>0.51) and in the DCP at a distance of up to 5° from the fixation point (R>0.49). The P1 amplitude correlates with the basal diameter of the hole (R= -0.38), the area of CC in the INL and the OPL+HFL complex (R> -0.33) and vessel density in the SCP (R=0.37) at a distance of up to 2.5° from the fixation point, as well as vessel density in the DCP at a distance of up to 5° from the fixation point (R=0.47). Vessel density in the DCP is significantly lower in the presence of CC in the retina (p<0.001).

CONCLUSION

In FTMH, there is a relationship between bioelectrical activity and LS, and structural disorders, capillary perfusion in different layers of the retina. A multimodal topographically oriented approach allows studying the relationship between structural and functional parameters in individual points of the retina and can be used in monitoring of FTMH after surgical treatment.

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.

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.

Choriocapillary regional characteristics in idiopathic macular holes using optical coherence tomography angiography

PURPOSE

To evaluate the characteristics of vascular density (VD) of the retinal capillary plexuses in idiopathic macular hole (IMH), the fellow eye, and healthy control eyes by optical coherence tomography angiography (OCTA).

METHODS

A retrospective cases series study involving 20 unilateral eyes (20 patients) with IMH, the unaffected fellow eyes (n = 20) and 20 health controls, with age- and sex-matched, was conducted in Shanxi Eye Hospital from January 2019 to December 2021. VD of the retinal capillary plexuses measurements were obtained by OCTA.

RESULTS

Four quadrants of superficial capillary plexuses (SCP) in IMH eyes were not significant compared with that in the unaffected fellow eyes (all P > 0.05). The four quadrants of deep capillary plexuses (DCP) in IMH eyes were lower than that in the unaffected fellow eyes (all P < 0.05). Different regions retinal thickness in the IMH eyes was higher than that in the unaffected fellow eyes (all P < 0.05). a significant negative correlation between deep vessel density and retinal thickness in different quadrants among IMH eyes (all P < 0.05). Additionally, the correlation between the vascular density of SCP and retinal thickness was significant in macular fovea area (= 0.519, P = 0.019). <0.001.

CONCLUSIONS

The morphology of retina and choroid in idiopathic macular hole is different from that in fellow eye. The thickness of choroid in the fovea area of the unaffected eye also showed a decreasing trend. Taken together, the mechanism of macular hole may be further understood, that is, the decrease of choroid thickness may occur before the macular hole formation. It was verified again that the choroidal blood flow area in macular fovea of IMH patients was significantly lower than that in fellow eyes and healthy eyes.

OCT ANGIOGRAPHY IN DISEASES OF THE VITREORETINAL INTERFACE

AIMS

Present the use of Optical Coherence Tomography Angiography (OCTA) in vitreoretinal interface diseases and results of macular capillary network evaluation before and after idiopathic macular hole surgery (IMD).

METHODOLOGY

Prospective evaluation of functional results, anatomical and OCTA findings before and after IMD surgery. The group consists of 8 eyes of eight patients. Preoperatively and 1, 3 and 6 months after surgery, the best corrected visual acuity (BCVA) was examined, fundus photography was performed, examination of the macula by spectral-domain optical coherence tomography (SD OCT), determination of the stage of IMD according to Gases and also OCTA examination. The area of the foveal avascular zone (FAZ) and vascular density (VD) were evaluated by using of the OCTA. The operation was performed in all cases by transconjunctival suture 25G vitrectomy by one surgeon, always peeling the inner limiting membrane. An expansive gas, 7x 20% SF6, 1x 15% C3F8, was used for vitreous tamponade.

RESULTS

In all 8 cases, the primary closure of the IMD occurred after the operation. The mean BCVA improved statistically significantly from 0.74 to 0.48 logMAR (p = 0.0023). The average FAZ area decreased from 0.345 mm² to 0.25 mm² after surgery (p = 0.0458). The mean VD increased from 7.93 mm-1 to 8.38 mm-1 (p = 0.2959).

CONCLUSIONS

Assessment of the macular capillary network in patients with diseases of the vitreoretinal interface offers new findings and important details that can lead to prognostic information and a better understanding of the pathogenesis of the disease. We demonstrated a statistically significant reduction in FAZ in the eyes after successful IMD surgery and an indirect relationship between the improvement of BCVA and the change in FAZ area in our cohort.

Intraretinal Cysts in Macular Hole: A Structure-Function Correlation Based on En Face Imaging

Purpose

To characterize retinal micromorphic changes on en face optical coherence tomography (OCT) and to determine their role in pathogenesis and visual outcomes in macular hole (MH) surgery.

Patients and Methods

This is a retrospective, interventional, consecutive case series of 28 eyes undergoing successful MH surgery. Pre- and post-operative en face OCT were manually segmented, and the correlation between parameters such as MH basal diameter and minimal inlet area, area of cyst in inner plexiform layer (IPL) and outer plexiform layer (OPL), percentage of cyst in IPL and OPL, and amount of ellipsoid zone (EZ) defect and external limiting membrane (ELM) defect was performed. Their relationship with visual acuity (VA) outcomes (Group 1: ≥20/60; 14 eyes; Group 2: <20/60; 14 eyes) was also evaluated.

Results

A significant positive correlation was noted between the cyst area in OPL and IPL (r=0.768; p<0.001), which in turn were positively correlated with the basal diameter of the MH in all eyes. The cyst area was significantly more in IPL as compared to OPL in all eyes (p=0.049) and in group 2 (p=0.03) but not in group 1 (p=0.62). As compared to group 2, eyes in group 1 had significantly better pre- and post-operative VA, and significantly smaller basal diameter, minimal inlet area, area of cyst in IPL and OPL, and amount of defect in the ELM (postoperative) and EZ (pre- and post-operative), respectively.

Conclusion

An increase in the basal diameter of the MH is associated with a simultaneous congruous enlargement of the area of cyst in IPL and OPL. Based on these imaging findings, we propose that the possible rationale for the origin of these intraretinal cysts could be a breakdown in the physiological retinal pigment epithelium (RPE) pump due to the anatomical separation of the neurosensory retina from the underlying RPE, ie, "RPE contact loss" theory.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FINDINGS BEFORE AND AFTER VITRECTOMY FOR MACULAR HOLES: Useful or Useless?

PURPOSE

To investigate the vascular remodeling of optical coherence tomography angiography in full-thickness macular hole surgery.

METHODS

This retrospective, observational case series included 33 eyes of 33 patients with a full-thickness macular hole who underwent epiretinal membrane removal. Data were collected on best-corrected visual acuity, structural B-scan optical coherence tomography, and optical coherence tomography angiography preoperatively and at 1, 3, and 6 months postoperatively. Optical coherence tomography angiography was used to assess the retinal vascular density (VD) of the superficial vascular plexus and deep vascular plexus (DVP). Vascular density was assessed using the Early Treatment Diabetic Retinopathy Study grid for the whole, inner, and outer grids.

RESULTS

A statistically significant correlation was found between the VD (whole, inner, and outer grids) of the superficial vascular plexus alone from baseline to 1-month postoperatively (P < 0.001). Similarly, VD was correlated from baseline to 1, 3, and 6 months postoperatively to the whole (P < 0.0005, F = 23.22), inner (P < 0.0005, F = 28.23), and outer Early Treatment Diabetic Retinopathy Study grids of DVP (P = 0.033, F = 3.49). The best-corrected visual acuity and VD were significantly correlated with the superficial vascular plexus and DVP at baseline and 6 months (P < 0.05, all correlations). The most significant correlation was observed at 6 months between best-corrected visual acuity and DVP in the whole, inner, and outer Early Treatment Diabetic Retinopathy Study grids (P < 0.001).

CONCLUSION

Superficial vascular plexus and DVP are affected by full-thickness macular holes, with the most significant effects being on the DVP. Full-thickness macular hole surgery leads to an improvement in the best-corrected visual acuity in many eyes and the restoration of the VD, especially of the DVP.

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.

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.

Long-term improvement of retinal sensitivity after macular hole surgery over at least 9-year-old follow-up: a case series

PURPOSE

To evaluate the correlations between anatomical and functional changes in idiopathic macular hole (IMH) surgery in long-term follow-up.

METHODS

This is a prospective, interventional single centre case series. The final sample is formed by 14 eyes of 14 patients who had undergone IMH surgery in our institution between 2005 and 2009 and were still followed up in 2019. Reported data were pre- and post-operative best-corrected visual acuity (BCVA), retinal sensitivity and fixation stability values on MP-1 and structural macular features on spectral domain optical coherence tomography. Optical coherence tomography angiography (OCTA) was utilized to assess microvascular characteristics at the final visit. Only patients with a successful MH closure were enrolled, excluding eyes affected by other relevant pathologies.

RESULTS

Mean BCVA improvement was significant after surgery (t test, p value < 0.001) and presented a slight, not statistically significant raise, between the post-operative and long-term follow-up. Differently, mean retinal sensibility (dB) showed a highly statistically significant difference between pre-operative and post-operative (t test, p value = .002) and post-operative and last follow-up (p value < 0.001). In the long-term follow-up, subjects having integrity of the inner segment/outer segment (IS/OS) layer showed no statistically significant difference in BCVA compared with subjects with IS/OS discontinuity (t test, p value = 0.72). OCTA parameters of the operated eye showed no statistical significance compared with the fellow eye.

CONCLUSIONS

In successfully closed MHs, retinal sensibility measured by microperimetry significatively increases after a long follow-up period even when BCVA remains stable or raises slightly. Vessel density organization tends to be quantitatively similar to fellow eye several years after surgery.

Fluorescein angiography versus optical coherence tomography angiography: FA vs OCTA Italian Study

PURPOSE

To assess the current role of fluorescein angiography after the introduction of optical coherence tomography angiography in real-life clinical practice.

METHODS

This was a multicentric retrospective observational study to evaluate the number of fluorescein angiography and optical coherence tomography angiography procedures performed by different devices from January 2013 to December 2018. The centers involved were Centro Italiano Macula (Rome), and ophthalmology departments of University "G. D'Annunzio" Chieti-Pescara (Chieti) and "Azienda Ospedaliero Universitaria Careggi" (Florence).

RESULTS

Out of 19,898 total fluorescein angiography procedures performed in the observation period, 3444 (17.3%) were in 2013, 3972 (19.9%) were in 2014, 3601 (18.1%) were in 2015, 3407 (17.2%) were in 2016, 3285 (16.5%) were in 2017, and 2189 (11%) were in 2018. Out of 7949 optical coherence tomography angiography procedures performed in the observation period, none were performed in 2013, 550 (6.9%) were in 2014, 908 (11.5%) were in 2015, 2098 (26.4%) were in 2016, 2090 (26.3%) were in 2017, and 2303 (28.9%) were in 2018.

CONCLUSION

Fluorescein angiography procedures were performed less often after the introduction of optical coherence tomography angiography technology. The ease, speed, and safety of the optical coherence tomography angiography procedure in everyday clinical practice have facilitated more optical coherence tomography angiography application compared to fluorescein angiography in recent years. In the future, we will probably evaluate the different pathologies that still need an evaluation by fluorescein angiography.

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.

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

Purpose

To present optical coherence tomography (OCT) angiography features in patients with idiopathic full-thickness macular hole before and after vitrectomy.

Study design

Prospective case series study.

Materials and methods

Patients presenting with an idiopathic full-thickness macular hole (IMH) who underwent posterior vitrectomy with internal limiting membrane peeling and gas tamponade were included in the study. En face OCT and OCT angiography (OCTA) was performed pre- and postoperatively using 3×3 mm scans (Optovue, XR Avanti). Foveal avascular zone (FAZ) area, macular hole size (MHS), central retinal thickness (CRT), macular parafoveal choriocapillary flow area (MCFA), and fovea vessel density (FVDS) were measured and assessed using OCTA. Best-corrected visual acuity (BCVA) was examined before and 3 months after surgery.

Results

Twenty-eight eyes of 28 patients were included in the study. The mean age of patient group was 68.28 years. The hole was closed in all eyes after the initial surgery. OCTA showed enlargement of FAZ and increased CRT in foveal area. Mean preoperative FAZ area was 0.39±0.07 mm². En face images of the middle retina showed a range of preoperative cystic patterns surrounding the hole. BCVA was improved from 0.1±0.11 preoperatively to 0.42±0.17 postoperatively. Mean FAZ area was reduced to 0.24±0.07 mm² postoperatively with resolution of macular hole and adjacent cystic areas. Mean CRT was reduced from 396±62.6 µm pre-operatively to 272±30.7 µm postoperatively. After vitrectomy, the parafoveal choriocapillary flow area and FVDS of IMH eyes increased compared with the preoperative measurements.

Conclusion

Quantitative evaluation of vascular and morphological changes following IMH surgery using OCTA shows the potential for recovery due to vascular and neuronal plasticity. OCTA showing vascular changes and their quantitative characteristics might be a useful tool for the assessment of macular holes before and after surgical treatment.

A new dye based on anthocyanins from the acai fruit (Euterpe oleracea) for chromovitrectomy in humans: clinical trial results

PURPOSE

To test the applicability of the acai dye at a 25% concentration for identifying the posterior hyaloids and internal limiting membranes (ILMs) during pars plana vitrectomy (PPV) in human eyes with macular holes (MHs).

METHODS

This study included 25 patients with chronic idiopathic MHs. The exclusion criteria included glaucoma, previous significant ocular conditions, and previous ocular surgeries except uncomplicated cataract. Ten surgeons performed 23-gauge four-port PPV, phacoemulsification, posterior hyaloid detachment, ILM peeling guided by dye staining, and perfluoropropane injection. The patients remained prone for 5 days postoperatively. The patients were evaluated postoperatively after 1, 30, and 180 days. The surgeons completed a questionnaire regarding the dye's staining abilities.

RESULTS

The posterior hyaloids and ILMs stained purple in all eyes. The final best-corrected visual acuity improved significantly (p < 0.001) from preoperatively (1.37 ± 0.29) to 180 days postoperatively (1.05 ± 0.43). The MHs closed in 76% of eyes.

CONCLUSION

The acai dye at a 25% concentration identified posterior hyaloids and ILMs during PPVs in humans. Dye toxicity was unlikely.

Foveal microvasculature features of surgically closed macular hole using optical coherence tomography angiography

Background

To describe the features of foveal microvasculature using optical coherence tomography angiography (OCTA) and to determine the related clinical factors in eyes with surgically closed macular hole (MH).

Methods

A retrospective case series of 18 patients with unilateral MH was reviewed. The patients maintained complete hole closure after vitrectomy with inner limiting membrane (ILM) peeling for at least 12 months. The healthy fellow eyes were studied as controls. The foveal microvasculature of both eyes was examined by OCTA. The area of the foveal avascular zone (FAZ) and the vascular density (VD) ratio in the superficial and deep capillary plexuses (SCP and DCP) were determined after surgery. Several clinical factors including age, stage and dimensions of MH, papillofoveal distance, the extent of nasal displacement of the fovea after surgery, postoperative central foveal thickness, and outer-retina integrity were evaluated to determine any relationships with the OCTA parameters.

Results

The mean FAZ area in both the SCP and DCP (0.29 ± 0.11 mm² and 0.39 ± 0.14 mm²) was significantly smaller than those of the controls (0.45 ± 0.14 mm² and 0.62 ± 0.22 mm²) (p = 0.001 and <0.001, respectively). The mean VD ratio in the SCP (0.270 ± 0.349) was similar to that of the controls (0.321 ± 0.189) (p = 0.231); however, that in the DCP (0.321 ± 0.189) was significantly lower than that of the controls (0.331 ± 0.119) (p = 0.025). Only the extent of nasal displacement of the fovea was correlated with the DCP FAZ-area difference values between the study group and the controls (correlation coefficient = 0.577; p = 0.012).

Conclusions

After successful MH surgery, the FAZ area in both the SCP and DCP was smaller and the VD ratio of the DCP was lower, suggesting a possible DCP vulnerability to tractional stress. As the FAZ area of the DCP in closed-MH eyes became smaller than that in the controls, the fovea was less displaced toward the optic disc, possibly reflecting a lack of retinal redundancy caused by horizontal stretching accompanied by foveal displacement.

Electronic supplementary material

The online version of this article (10.1186/s12886-017-0607-z) contains supplementary material, which is available to authorized users.