Spectral domain optical coherence tomography in the diagnosis and management of vitreoretinal interface pathologies

Effect of the macular shape on hole findings in idiopathic macular hole differs depending on the stage of the macular hole

This study aimed to investigate the relationship between macular shape and idiopathic macular hole (MH) findings using an objective method. We present retrospective observational case series on patients with MH. The shape of the macular area was quantified using quadratic equations, and the ocular shape (OS) index was calculated. The correlation between the OS index and macular hole findings for each stage was evaluated. Pearson's correlation coefficient showed a significant correlation between the OS index and horizontal hole diameter (p = 0.044), bottom diameter (p = 0.006), and vertical bottom diameter (p = 0.024) in stage 2. For stage 4, there was a negative and significant correlation between the OS index and age (p = 0.037), and horizontal (p = 0.021) and vertical (p = 0.027) bottom diameter. Multiple regression analysis showed that the horizontal (p = 0.0070) and vertical (p = 0.031) bottom diameter and OS index were independently and positively correlated in stage 2. In stage 4, the OS index was independently and negatively correlated with the horizontal (p = 0.037) and vertical (p = 0.048) bottom diameter. The ocular shape of the macula affects MH findings, and its impact depends on its stage.

Primary Lamellar Macular Holes: To Vit or Not to Vit

There is a wide spectrum of macular conditions that are characterized by an irregular foveal contour caused by a break in the inner fovea. These include full-thickness macular hole (FTMH), foveal pseudocyst, lamellar macular hole (LMH) and macular pseudohole (MPH). Clinical examination of vitreomacular interface disorders is notoriously poor in differentiating these conditions. These conditions were initially described with slit-lamp biomicroscopy, and the main goal was to distinguish an FTMH from the others. The introduction of optical coherence tomography (OCT) has revolutionized our understanding of the foveal microstructural anatomy and has facilitated differentiating these conditions from an FTMH. However, the definitions of the other conditions, particularly LMH, has evolved over the past two decades. Initially the term LMH encompassed a wide spectrum of clinical conditions. As OCT became more widely used and observations became more refined, two different phenotypes of LMH became apparent, raising the question of different pathogenic mechanisms for each phenotype. Tractional and degenerative pathological mechanisms were proposed. Epiretinal membranes (ERMs) associated with each phenotype were identified. Typical ERMs were associated with a tractional mechanism, whereas an epiretinal proliferation was associated with a degenerative mechanism. Epiretinal proliferation represents Müller cell proliferation as a reactive process to retinal injury. These two types of ERM were differentiated by their characteristics on SD-OCT. The latest consensus definitions take into account this phenotypic differentiation and classifies these entities into LMH, MPH and ERM foveoschisis. The initial event in both ERM foveoschisis and LMH is a tractional event that disrupts the Müller cell cone in the foveola or the foveal walls. Depending on the extent of Müller cell disruption, either a LMH or an ERM foveoschisis may develop. Although surgical intervention for LMH remains controversial and no clear guidelines exist for pars plana vitrectomy (PPV), eyes with symptomatic, progressive ERM foveoschisis and LMH may benefit from surgical intervention.

Vitreomacular Interface Abnormalities in Myopic Foveoschisis: Correlation With Morphological Features and Outcome of Vitrectomy

Purpose: To compare the morphologic characteristics and response to surgery of myopic foveoschisis (MF) with different patterns of vitreomacular interface abnormalities (VMIAs).

Methods: In this observational case series, 158 eyes of 121 MF patients with epiretinal membrane (ERM) or vitreomacular traction (VMT) based on optical coherence tomography (OCT) were enrolled. All the eyes were divided into two groups by the pattern of VMIAs: ERM and VMT group. Sixty-one eyes underwent pars plana vitrectomy (PPV) and were followed up for at least 6 months. The morphologic characteristics based on OCT and the surgical outcome were evaluated.

Outcome: ERM and VMT were found in 47.47 and 52.53% of the cases, respectively. A higher rate of foveal detachment (61.4 vs. 26.7%; p < 0.001) and a higher rate of outer lamellar macular hole (45.8 vs. 21.3%; p = 0.001) were detected in the eyes with VMT compared with those with ERM. In contrast, a lower rate of inner lamellar macular hole (28.9 vs. 60.0%; p = 0.001) was detected in the eyes with VMT compared with those with ERM. The disruption of the external limiting membrane (ELM) was more common in the eyes with VMT than in those with ERM (45.8 vs. 21.3%; p = 0.001). PPV was performed in 61 eyes with a mean follow-up time of 23.55 ± 19.92 months. After surgery, anatomical resolution was achieved in 51 eyes (83.6%). At the final visit, the mean central foveal thickness (CFT) decreased significantly from 547.83 to 118.74 μm, and the mean LogMAR BCVA improved significantly from 0.92 to 0.57. The VMT group was associated with a higher proportion of eyes with visual acuity improvement postoperatively (p = 0.02) and had more a decrease of CFT (P = 0.007) compared with the ERM group.

Conclusion: In the eyes with MF, outer retinal lesions occurred more frequently in the eyes with VMT, whereas inner retinal lesions occurred more frequently in the eyes with ERM. Tangential force generated by ERM may act as a causative factor for the inner retinal lesions in MF, and inward-directed force resulting from VMT may act as a causative factor for outer retinal lesions in MF.

Choroidal thickness in lamellar macular holes

PURPOSE

(1) To assess the thickness of the central choroid (BM-CSI) in swept-source optical coherence tomography (SS-OCT) examination of lamellar macular holes (LMHs). (2) To establish correlations between the thickness of the central choroid (BM-CSI) in the LHM and the parameters of best-corrected visual acuity and reading vision in patients with LMH.

METHODS

This prospective case-control study assessed a group of 30 patients (30 eyes) with LMHs and a control group of 45 patients (90 eyes). The thickness of the central choroid (BM-CSI) was measured with an SS-OCT device. The average choroidal thickness in the fovea was defined as average thickness in the central area of 1000 μm in diameter, according to the Early Treatment Diabetic Retinopathy Study (ETDRS). The results were correlated with best-corrected visual acuity (BCVA), and reading vision.

RESULTS

The average choroidal thickness in the study group (SG) with LMH was 160.34 μm (SD = 77.1), whereas in the control group (CG), it was 225.11 μm (SD = 93.8). The difference of 64.77 μm was statistically significant (p < 0.05). The BCVA was within the range between 0.7 (logMAR) and 0.1 (logMAR), with an average of 0.36 (logMAR) (SD = 0.23). Reading vision was within the range between - 0.2 (logMAR) and 0.3 (logMAR), with an average of 0.27 (logMAR) (SD = 0.12). A significant correlation between BCVA and the choroid (BM-CSI) was found. The correlation coefficient is average (r = 0.44) and positive. With better BCVA, a significantly thicker choroid (BM-CSI) can be observed. No significant correlation between BM-CSI and reading vision was found. The correlation coefficient value is minor (r = - 0.289), whereas lower values of BM-CSI can be observed with worse reading vision.

CONCLUSION

We suggest that the choroid may take part in the pathogenesis of LMH development. Its significant thinning may be responsible for the ischemic degenerative mechanism degenerating outer layers of retina, apart from tractional mechanism.

A multi-center study of prediction of macular hole status after vitrectomy and internal limiting membrane peeling by a deep learning model

Background

To develop a deep learning (DL) model for prediction of idiopathic macular hole (MH) status after vitrectomy and internal limiting membrane peeling (VILMP) based on optical coherence tomography (OCT) images from four ophthalmic centers.

Methods

Eyes followed up at 1 month after VILMP for full-thickness MH were included. In the internal training set, 920 preoperative macular OCT images (as the input) and post-operative status of MH (closed or open, as the output) of 256 eyes from two ophthalmic centers were used to train the DL model using VGG16 algorithm. In the external validation set, 72 preoperative macular OCT images of 36 MH eyes treated by VILMP from another two ophthalmic centers were used to validate the prediction accuracy of the DL model.

Results

In internal training, the mean of overall accuracy for prediction of MH status after VILMP was 84.6% with a mean area under the receiver operating characteristic (ROC) curve (AUC) of 91.04% (sensitivity 85.37% and specificity 81.99%). In external validation, the overall accuracy of predicting MH status after VILMP was 84.7% with an AUC of 89.32% (sensitivity 83.33% and specificity 87.50%). The heatmaps showed that the area critical for prediction was at the central macula, mainly at the MH and its adjacent retina.

Conclusions

The DL model trained by preoperative macular OCT images can be used to predict postoperative MH status after VILMP. The prediction accuracy of our DL model has been validated by multiple ophthalmic centers.

OBSERVATION OF VITREOUS FEATURES USING ENHANCED VITREOUS IMAGING OPTICAL COHERENCE TOMOGRAPHY IN HIGHLY MYOPIC RETINOSCHISIS

PURPOSE

To observe features of the posterior vitreous and vitreoretinal interface in highly myopic eyes with retinoschisis using enhanced vitreous imaging optical coherence tomography.

METHODS

Comprehensive ophthalmologic examination and enhanced vitreous imaging optical coherence tomography were performed in 77 eyes of 63 patients with highly myopic retinoschisis. Two different modes of spectral domain optical coherence tomography were employed to estimate retinoschisis and the posterior vitreous features in optical coherence tomography images, respectively. The types and distribution of vitreoretinal interface abnormalities were also analyzed.

RESULTS

Complete posterior vitreous detachment (PVD) was identified in 55 eyes (71.4%) with a Weiss ring. Residual cortex was found in 39 eyes (70.9%) with complete PVD. Vitreoretinal interface changes, including vitreoretinal adhesion and epiretinal membrane (ERM), most frequently appeared in the macular area (47.3%), followed by the inferior arched vessels region (34.5%). In partial PVD eyes, vitreoretinal traction, vitreoretinal adhesion, and epiretinal membrane tended to be observed in the inferior and superior arched vessels regions (54.5 and 40.9%, respectively). Among all types of vitreoretinal interface abnormalities, epiretinal membrane comprised the largest proportion (46.8%) despite the status of PVD. The presence of inner layers of retinoschisis connoted a relatively high possibility of vitreoretinal interface abnormalities occurring.

CONCLUSION

Enhanced vitreous imaging optical coherence tomography reveals a high prevalence of vitreoretinal interface abnormalities in highly myopic eyes with retinoschisis. Vitreous cortex tends to remain on the macular area in eyes with complete PVD. Our findings may lead to better guidance for the surgical treatment of highly myopic retinoschisis.

Coexistence of Peripheral Retinal Diseases with Macular Hole

Objectives:

To investigate the frequency of retinal tear, retinal hole, and lattice degeneration in peripheral retinal examination of patients with macular hole.

Materials and Methods:

The files of patients who underwent pars plana vitrectomy surgery with a diagnosis of macular hole at Eskişehir Osmangazi University Department of Ophthalmology between 2008 and 2018 were retrospectively analyzed. A total of 106 patients with primary macular hole who underwent peripheral retinal examination were included in the study. The frequency of retinal tears, holes, and lattice degeneration associated with macular hole was investigated.

Results:

Peripheral retinal examination of 106 patients who underwent macular hole surgery revealed retinal tear in 3 patients (2.8%), retinal hole in 4 patients (3.8%), and lattice degeneration in 10 patients (9.4%). Retinal hole and lattice degeneration were observed concomitantly in 1 patient.

Conclusion:

This study showed that patients with macular hole have concomitant retinal tears and holes, which are also thought to arise due to vitreoretinal traction, at a frequency similar to that in the general population. This result suggests that both the anterior and posterior vitreous may have different pathologies at the same time related to these diseases.

Pathogenesis and Management of Macular Hole: Review of Current Advances

Macular hole has been believed to be a disorder of vitreomacular interface, which forms as a result of abnormal vitreous traction from incomplete vitreous detachment. However, our recent studies demonstrated that dynamic forces, caused by mobile posterior cortical vitreous with fluid currents, exist already at early stages of macular hole development. Therefore, in eyes with flexible vitreous, the contributions of tractional forces due to vitreous shrinkage are unlikely. These facts indicate that in the development of idiopathic macular holes, there is a greater contribution of dynamic forces than has been previously reported. This review also evaluates the recent findings in the assessment of the idiopathic macular holes and the recent therapeutic strategies for optimal management. Inner limiting membrane is considered to improve anatomical closure rate; however, it is still questionable if peeling is necessary in holes less than 250 µm. There are plenty of publications indicating that in the management of small and medium size hole (less than 400 µm), use of long-lasting gas and face-down position is not always required; however, it may be necessary for the treatment of large holes. Ocriplasmin and expansile gas had been reported to be successful for management of small- and medium-sized holes and vitreomacular attachment.

Thickness of the Macula, Retinal Nerve Fiber Layer, and Ganglion Cell-inner Plexiform Layer in the Macular Hole: The Repeatability Study of Spectral-domain Optical Coherence Tomography

Purpose

We measured the thicknesses of the ganglion cell and inner plexiform layer (GCIPL), the macula, and the retinal nerve fiber layer (RNFL) using spectral-domain optical coherence tomography in patients with idiopathic macula holes to analyze the repeatability of these measurements and compare them with those of the fellow eye.

Methods

We evaluated 85 patients who visited our retinal clinic. The patients were divided into two groups according to their macular hole size: group A had a size of <400 µm, while group B had a size of ≥400 µm. Repeatability was determined by comparing the thicknesses of the GCIPL, macula, and RNFL with those of the normal fellow eye.

Results

The average central macular thickness in patients with macular holes was significantly thicker than that in the normal fellow eye (343.8 ± 78.6 vs. 252.6 ± 62.3 µm, p < 0.001). The average thickness of the GCIPL in patients with macular holes was significantly thinner than that in the normal fellow eye (56.1 ± 23.4 vs. 77.1 ± 12.8 µm, p < 0.001). There was no significant difference in the average RNFL thickness between eyes with macular holes and fellow eyes (92.4 ± 10.0 vs. 95.5 ± 10.7 µm, p = 0.070). There were also no significant differences in the thicknesses of the GCIPL and RNFL among the two groups (p = 0.786 and p = 0.516). The intraclass correlation coefficients for the macula and RNFL were 0.994 and 0.974, respectively, in patients with macular holes, while that for the GCIPL was 0.700.

Conclusions

Macular contour change with macular hole results in low repeatability and a tendency of thinner measurement regarding GCIPL thickness determined via spectral-domain optical coherence tomography. The impact of changes in the macular shape caused by macular holes should be taken into consideration when measuring the GCIPL thickness in patients with various eye diseases such as glaucoma and in those with neuro-ophthalmic disorders.

Efficacy of non-fovea-sparing ILM peeling for symptomatic myopic foveoschisis with and without macular hole

AIM

To study anatomical and visual outcomes of pars plana vitrectomy (PPV) with non-fovea-sparing (entire) internal limiting membrane (ILM) peeling in eyes with myopic foveoschisis (MF).

METHODS

Prospective interventional case series of eyes undergoing PPV with entire ILM peeling for symptomatic MF.

MAIN OUTCOME MEASURES

Preoperative spectral domain optical coherence tomography (SD-OCT) epiretinal membrane, anomalous posterior vitreous detachment, vitreoschisis and postoperative changes in SD-OCT central foveal thickness (CFT), ellipsoid zone defect, foveal detachment (FD), macular hole (MH) diameter (if present) and best-corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution (logMAR).

RESULTS

This study included 21 eyes (21 patients) with mean age 60.4±13.1, 15 females (71.4%). All patients achieved complete postoperative reattachment by SD-OCT (no FD) 6 months post vitrectomy, with no iatrogenic intraoperative or postoperative MH, and with significant improvement in final BCVA from 1.6±0.30 to1.0±0.2 logMAR, and in CFT from 918.2±311.4 to182.3±33.1 µm. Patients were subdivided into subgroup A: 11 eyes without MH; and subgroup B: 10 eyes with MH, the latter had significant improvement in MH diameter (p=0.005). Preoperative BCVA was a significant risk factor for visual gain, while preoperative FD and CFT were significant for CFT change.

CONCLUSION

Vitrectomy with non-fovea-sparing (entire) ILM peeling resulted in a significant functional and anatomical improvement in eyes with MF with/without MH with no reported complications. Results are comparable to fovea-sparing ILM peeling.

Autologous neurosensory retinal free patch transplantation for persistent full-thickness macular hole

PURPOSE

To evaluate anatomical and functional outcomes after autologous neurosensory retinal free patch (ANRFP) transplantation for persistent idiopathic full-thickness macular hole (iFTMH).

METHODS

A 65-year-old woman with persistent macular hole in her right eye after previous 27-gauge pars plana vitrectomy with internal limiting membrane peeling and long-acting gas tamponade underwent ANRFP transplantation. Before surgery, best corrected visual acuity in her right eye was 20/800. Optical coherence tomography (OCT) showed a 715-micron-diameter FTMH. To treat the persistent FTMH, a small autologous neurosensory retinal patch was transplanted and placed inside the macular hole under perfluorocarbon liquids (PFCL). PFCL-air exchange was performed, and long-acting gas tamponade was carried out. Clinical features of the macular area, visual acuity (VA), fundus autofluorescence, microperimetry and OCT were recorded during the 10-month follow-up.

RESULTS

The macular hole appeared successfully closed with retinal patch stable and well plugged into the hole during the whole follow-up. VA improved to 20/100 and microperimetry revealed an increase in mean retinal sensitivity from 14.7 dB at 1 month to 15.6 dB at 10 months postoperatively. OCT showed a well-distinguishable retinal patch into the hole 1 month after surgery and a completely integrated retinal patch between the retinal layers 10 months postoperatively. No intra- and postoperative complications were noticed.

CONCLUSIONS

ANRFP transplantation may represent an innovative technique for persistent iFTMH treatment.

Vitreomacular Interface Disorders in Behçet's Uveitis

Objectives:

To determine the prevalence of vitreomacular interface (VMI) disorders in patients with Behçet’s uveitis and assess the relationship between VMI disorders and clinical characteristics.

Materials and Methods:

The macular optical coherence tomography (OCT) images of 160 eyes of 96 patients with Behçet’s uveitis who were being followed in the Uvea-Behçet’s clinic were assessed retrospectively for VMI disorders including posterior vitreous detachment (PVD), epiretinal membrane (ERM), vitreomacular adhesion (VMA), vitreomacular traction (VMT), full-thickness macular hole (FTMH), lamellar hole (LH) and pseudohole.

Results:

Twenty-four patients (25%) with unilateral and 72 patients with bilateral uveitis were included in the study. Six (30%) of 20 eyes with anterior uveitis and 57 (40.7%) of 140 eyes with posterior uveitis, in total 63 (39.4%) eyes of 160 eyes had at least one VMI disorder. PVD was detected in 4 eyes (2.5%), ERM in 48 eyes (30%), VMA in 12 eyes (7.5%), and LH in 1 eye (0.6%). None of the eyes had VMT, FTMH, or pseudohole. ERM was detected in 13 eyes (8.1%) on fundus examination and 48 (30%) eyes by OCT (p=0.001). VMI was detected in 12 (50%) of 24 eyes with prior intraocular surgery and 51 (37.5%) of 136 eyes without. The mean duration of uveitis was 7.3±5.8 years in patients with VMI disorders and 5.8±7.7 years in patients without (p=0.04). There was no relation between VMI disorders and anatomic location of uveitis, history of past ocular surgery, number of ocular/periocular steroid injections, or visual acuity.

Conclusion:

VMI disorders are common in patients with Behçet’s uveitis. Their frequency increases with the duration of uveitis. OCT is more sensitive than fundus examination in the detection of VMI disorders.

[Pharmaological vitreolysis with ocriplasmin as a treatment option for symptomatic focal vitreomacular traction with or without macular holes (≤400 μm) compared to tranconjunctival vitrectomy]

BACKGROUND

To evaluate the resolution rate in patients with symptomatic vitreomacular traction (VMT) ≤ 1500 μm with or without macular holes ≤ 400 μm after therapy with intravitreal ocriplasmin (Jetrea®) injections in a clinical setting in comparison to transconjunctival vitrectomy.

MATERIALS AND METHODS

We examined 21 eyes of 21 consecutive patients with vitreomacular traction with or without macular holes who underwent intravitreal injection of 0.1 ml ocriplasmin and we retrospectively reviewed 18 eyes of 18 patients with VMT with or without FTMH who underwent 23-gauge vitrectomy.

RESULTS

Vitreomacular traction resolved in 15 of 21 eyes treated with ocriplasmin after 6 month (71 %) compared to 100 % of eyes treated by vitrectomy. Of the 5 eyes that initially presented FTMH with VMT in the ocriplasmin group, 2 were closed 1 month after ocriplasmin treatment. The remaining 3 had vitrectomy and closed thereafter. Best corrected visual acuity was 0.38 ± 0.23 LogMAR at baseline, improving to 0.34 ± 0.24 LogMAR at 6 months after ocriplasmin treatment. Best corrected visual acuity in the vitrectomy group improved from 0.55 ± 0.29 LogMAR before operation to 0.53 ± 0.51 LogMAR 6 months postoperatively. Foveal thickness was 355.95 ± 114.53 μm at baseline, reducing to 277.77 ± 40.26 μm at 6 months after ocriplasmin treatment. Foveal thickness of eyes that underwent vitrectomy was 494.61 ± 126.02 μm at baseline, decreasing to 330.2 ± 88.85 μm 6 months postoperatively.

CONCLUSION

When traction is ≤ 1500 μm, enzymatic vitreolysis with ocriplasmin is a therapeutic option. In the presence of VMT >1500 μm or ERM, surgical treatment with vitrectomy is associated with better outcomes. In small macular holes with VMT and in the absence of ERM, enzymatic vitreolysis with ocriplasmin is an option. In cases of holes >400 μm, or in the absence of evident VMT, or in the presence of ERM, vitrectomy is the first choice.

Adaptive optics assisted and optical coherence tomography guided fs-laser system for ophthalmic surgery in the posterior eye

While fs-lasers are clinically established for surgery in the anterior eye, their use in the posterior eye is impeded by aberrations and focus position errors. We implemented a laboratory system to investigate whether fs-laser surgery in the posterior eye is made more feasible by aberration correction and tomographic image guidance. Aberration correction is obtained by adaptive optics (AO) and the image guidance is accomplished by optical coherence tomography (OCT). System characteristic measurements and cutting experiments were performed inside an eye model. By aberration correction, wavefront errors were reduced from 270 nm root-mean-square (rms) to 64 nm rms, ignoring Zernike terms for tilts and focus. The Strehl ratio of the assigned point spread function is improved from 0.11 to 0.78. The threshold pulse energy of laser-induced optical breakdown in water is lowered from about 3.0 to about 1.3???J measured at the eye model entrance. After laser cutting of a synthetic foil placed 300???m in front of porcine retinal tissue with the corrected system, postoperative three-dimensional OCT imaging showed no lesions in the tissue. Our results corroborate that AO and OCT will be two essential assistive components for possible clinical systems for fs-laser–based surgery in the posterior eye.

SPONTANEOUS CLOSURE OF A MACULAR HOLE AFTER FOUR FAILED VITRECTOMIES IN THE SETTING OF NF-1

PURPOSE

To present the case of a patient who developed spontaneous closure of an idiopathic macular hole after four failed attempts at surgical closure.

METHODS

This is a retrospective case review of the medical record of a single patient. No statistical analysis was performed. The patient is a 71-year-old white woman with neurofibromatosis Type 1 who presented to the retina clinic of one of the authors.

RESULTS

The patient underwent four vitrectomies with long acting gas by two surgeons over the course of 2 years. After each surgery, the hole either did not close or it closed and then reopened within 1 year. Five months after the last surgery (1 year after the hole last reopened), the patient presented with improved vision and spontaneous closure of the macular hole. The hole has remained closed since then.

CONCLUSION

This case demonstrates that spontaneous closure of a macular hole, associated with excellent visual recovery, can occur after multiple surgical failures. We propose that enhanced scar formation due to neurofibromatosis Type 1 was responsible for both the numerous failures following initially successful surgery (centrifugal traction) and for the spontaneous closure (centripetal traction).

Novel perspectives on swept-source optical coherence tomography

Technologies for multimodal digital imaging of vitreoretinal diseases have improved the accuracy of diagnosis and the depth of the knowledge of the mechanisms of disease and their response to treatments. Optic coherence tomography (OCT) has become a mandatory tool for the management and for the follow-up of retinal pathologies. OCT technology evolved in the last two decades from time-domain to spectral domain and recently to the swept-source OCTs (SS-OCT). SS-OCT improved the depth of imaging and the scan speed, thus adding novel algorithms and features such as for vitreous and vitreoretinal interface evaluation, choroid segmentation and mapping, OCT angiography and En-face OCT. The multimodal approach using SS-OCT is expected to advance the understanding of retinal pathologies such as age related macular degeneration, diabetic maculopathy, central serous chorioretinopathy, the pachychoroid spectrum and macular telangiectasia. Surgical vitreoretinal diseases such as vitreo-macular traction syndrome, epiretinal membrane, retinal detachment, proliferative vitreoretinal retinopathy and diabetic traction retinal detachment also will be better understood and documented with SS-OCT. This technology also provides great utility for a broad spectrum of ophthalmic pathologies including glaucoma, uveitis, tumors and anterior segment evaluation.

Three-Dimensional Enhanced Imaging of Vitreoretinal Interface in Diabetic Retinopathy Using Swept-Source Optical Coherence Tomography

PURPOSE

To analyze the vitreoretinal interface in diabetic eyes using 3-dimensional wide-field volumes acquired using high-speed, long-wavelength swept-source optical coherence tomography (SSOCT).

DESIGN

Prospective cross-sectional study.

METHODS

Fifty-six diabetic patients (88 eyes) and 11 healthy nondiabetic controls (22 eyes) were recruited. Up to 8 SSOCT volumes were acquired for each eye. A registration algorithm removed motion artifacts and merged multiple SSOCT volumes to improve signal. Vitreous visualization was enhanced using vitreous windowing method.

RESULTS

Of 88 diabetic eyes, 20 eyes had no retinopathy, 21 eyes had nonproliferative diabetic retinopathy (NPDR) without macular edema, 20 eyes had proliferative diabetic retinopathy (PDR) without macular edema, and 27 eyes had diabetic macular edema (DME) with either NPDR or PDR. Thick posterior hyaloid relative to healthy nondiabetic controls was observed in 0 of 20 (0%) diabetic eyes without retinopathy, 4 of 21 (19%) eyes with NPDR, 11 of 20 (55%) eyes with PDR, and 11 of 27 (41%) eyes with DME (P = .0001). Vitreoschisis was observed in 6 of 22 (27%) healthy nondiabetic eyes, 9 of 20 (45%) diabetic eyes without retinopathy, 10 of 21 (48%) eyes with NPDR, 13 of 20 (65%) eyes with PDR, and 17 of 27 (63%) eyes with DME (P = .007). While no healthy nondiabetic controls and diabetic eyes without retinopathy had adhesions/pegs between detached posterior hyaloid and retina, 1 of 21 (4%), 11 of 20 (55%), and 11 of 27 (41%) eyes with NPDR, PDR, and DME, respectively, demonstrated this feature (P = .0001).

CONCLUSION

SSOCT with motion-correction and vitreous windowing provides wide-field 3-dimensional information of vitreoretinal interface in diabetic eyes. This may be useful in assessing progression of retinopathy, planning diabetic vitreous surgery, and predicting treatment outcomes.

Optimal management of idiopathic macular holes

This review evaluates the current surgical options for the management of idiopathic macular holes (IMHs), including vitrectomy, ocriplasmin (OCP), and expansile gas use, and discusses key background information to inform the choice of treatment. An evidence-based approach to selecting the best treatment option for the individual patient based on IMH characteristics and patient-specific factors is suggested. For holes without vitreomacular attachment (VMA), vitrectomy is the only option with three key surgical variables: whether to peel the inner limiting membrane (ILM), the type of tamponade agent to be used, and the requirement for postoperative face-down posturing. There is a general consensus that ILM peeling improves primary anatomical hole closure rate; however, in small holes (<250 µm), it is uncertain whether peeling is always required. It has been increasingly recognized that long-acting gas and face-down positioning are not always necessary in patients with small- and medium-sized holes, but large (>400 µm) and chronic holes (>1-year history) are usually treated with long-acting gas and posturing. Several studies on posturing and gas choice were carried out in combination with ILM peeling, which may also influence the gas and posturing requirement. Combined phacovitrectomy appears to offer more rapid visual recovery without affecting the long-term outcomes of vitrectomy for IMH. OCP is licensed for use in patients with small- or medium-sized holes and VMA. A greater success rate in using OCP has been reported in smaller holes, but further predictive factors for its success are needed to refine its use. It is important to counsel patients realistically regarding the rates of success with intravitreal OCP and its potential complications. Expansile gas can be considered as a further option in small holes with VMA; however, larger studies are required to provide guidance on its use.

The Vitreomacular Interface in Diabetic Retinopathy

Diabetic retinopathy (DR) is a leading health concern and a major cause of blindness. DR can be complicated by scar tissue formation, macular edema, and tractional retinal detachment. Optical coherence tomography has found that patients with DR often have diffuse retinal thickening, cystoid macular edema, posterior hyaloid traction, and tractional retinal detachment. Newer imaging techniques can even detect fine tangential folds and serous macular detachment. The interplay of the vitreous and the retina in the progression of DR involves multiple chemokine and other regulatory factors including VEGF. Understanding the cells infiltrating pathologic membranes at the vitreomacular interface has opened up the possibility of new targets for pharmacotherapy. Vitrectomies for DR remain a vital tool to help relieve tension on the macula by removing membranes, improving edema absorption, and eliminating the scaffold for new membrane formation. Newer treatments such as triamcinolone acetonide and VEGF inhibitors have become essential as a rapid way to control DR at the vitreomacular interface, improve macular edema, and reduce retinal neovascularization. These treatments alone, and in conjunction with PRP, help to prevent worsening of the VMI in patients with DR.

Retinal Changes Induced by Epiretinal Tangential Forces

Two kinds of forces are active in vitreoretinal traction diseases: tangential and anterior-posterior forces. However, tangential forces are less characterized and classified in literature compared to the anterior-posterior ones. Tangential epiretinal forces are mainly due to anomalous posterior vitreous detachment (PVD), vitreoschisis, vitreopapillary adhesion (VPA), and epiretinal membranes (ERMs). Anomalous PVD plays a key role in the formation of the tangential vectorial forces on the retinal surface as consequence of gel liquefaction (synchysis) without sufficient and fast vitreous dehiscence at the vitreoretinal interface. The anomalous and persistent adherence of the posterior hyaloid to the retina can lead to vitreomacular/vitreopapillary adhesion or to a formation of avascular fibrocellular tissue (ERM) resulting from the proliferation and transdifferentiation of hyalocytes resident in the cortical vitreous remnants after vitreoschisis. The right interpretation of the forces involved in the epiretinal tangential tractions helps in a better definition of diagnosis, progression, prognosis, and surgical outcomes of vitreomacular interfaces.

Redesigning services for the management of vitreomacular traction and macular hole

Vitreomacular traction (VMT) and VMT with macular hole (MH) are serious conditions, being associated with visual disturbance, for example, metamorphopsia, and diminished visual acuity (VA). Pars plana vitrectomy is the routine treatment for symptomatic VMT and VMT+MH. However, ocriplasmin has demonstrated favourable efficacy and safety in specific patient groups with VMT/MH and is now recommended as a treatment option for certain patients by the National Institute of Health and Care Excellence. This means that services for managing patients with VMT/MH may need to be revised, as patients can now potentially receive treatment earlier in the course of the disease. VMT triage clinics could provide a more efficient way of managing VMT/MH patients. Patient assessment should always include high-definition optical coherence tomography, as this is the most accurate means of assessing abnormalities in the vitreoretinal (VR) interface, and an accurate measurement of best-corrected VA. It has been proposed that patients with VMT+MH be managed as a routine 6-week referral, with the complete patient journey—from initial referral to treatment—taking no longer than 6 months. It is important that patients are entered onto VR surgical lists so that there is no delay if ocriplasmin treatment is unsuccessful. Patients will need appropriate counselling about the expected outcomes and possible side effects of ocriplasmin treatment. One-year follow-up data should be collected by treatment centres in order to evaluate the new VMT service.

Clinical course of vitreomacular adhesion managed by initial observation

PURPOSE

The purpose of the study was to investigate the clinical course of patients with idiopathic vitreomacular adhesion (VMA).

METHODS

A noncomparative case series of patients who had clinical symptoms and spectral-domain optical coherence tomography findings consistent with VMA. The VMA was graded based on the optical coherence tomography findings at initial and follow-up examinations. Grade 1 was incomplete cortical vitreous separation with attachment at the fovea, Grade 2 was the Grade 1 findings and any intraretinal cysts or clefts, and Grade 3 was the Grade 2 findings and the presence of subretinal fluid.

RESULTS

One hundred and six eyes of 81 patients were identified as having VMA by spectral-domain optical coherence tomography at 3 retina clinics. The mean age was 73 years and the mean time of follow-up was 23 months. Forty-three eyes (41%) had Grade 1 VMA, 56 eyes (52%) had Grade 2 VMA, and 7 eyes (7%) had Grade 3 VMA. By the last follow-up, spontaneous release of VMA occurred in 34 eyes (32%), and pars plana vitrectomy was performed in 5 eyes (4.7%). Mean best-corrected visual acuity was 0.269 logarithm of the minimum angle of resolution or 20/37 at baseline (range, 20/20-20/200) and logarithm of the minimum angle of resolution 0.251 or 20/35 at the last examination (range, 20/20-20/400).

CONCLUSION

In this selected patient cohort with mild symptoms, the clinical course of patients with VMA managed by initial observation was generally favorable.

Enhanced vitreous imaging in healthy eyes using swept source optical coherence tomography

PURPOSE

To describe enhanced vitreous imaging for visualization of anatomic features and microstructures within the posterior vitreous and vitreoretinal interface in healthy eyes using swept-source optical coherence tomography (SS-OCT). The study hypothesis was that long-wavelength, high-speed, volumetric SS-OCT with software registration motion correction and vitreous window display or high-dynamic-range (HDR) display improves detection sensitivity of posterior vitreous and vitreoretinal features compared to standard OCT logarithmic scale display.

DESIGN

Observational prospective cross-sectional study.

METHODS

Multiple wide-field three-dimensional SS-OCT scans (500×500A-scans over 12×12 mm2) were obtained using a prototype instrument in 22 eyes of 22 healthy volunteers. A registration motion-correction algorithm was applied to compensate motion and generate a single volumetric dataset. Each volumetric dataset was displayed in three forms: (1) standard logarithmic scale display, enhanced vitreous imaging using (2) vitreous window display and (3) HDR display. Each dataset was reviewed independently by three readers to identify features of the posterior vitreous and vitreoretinal interface. Detection sensitivities for these features were measured for each display method.

RESULTS

Features observed included the bursa premacularis (BPM), area of Martegiani, Cloquet's/BPM septum, Bergmeister papilla, posterior cortical vitreous (hyaloid) detachment, papillomacular hyaloid detachment, hyaloid attachment to retinal vessel(s), and granular opacities within vitreous cortex, Cloquet's canal, and BPM. The detection sensitivity for these features was 75.0% (95%CI: 67.8%-81.1%) using standard logarithmic scale display, 80.6% (95%CI: 73.8%-86.0%) using HDR display, and 91.9% (95%CI: 86.6%-95.2%) using vitreous window display.

CONCLUSIONS

SS-OCT provides non-invasive, volumetric and measurable in vivo visualization of the anatomic microstructural features of the posterior vitreous and vitreoretinal interface. The vitreous window display provides the highest sensitivity for posterior vitreous and vitreoretinal interface analysis when compared to HDR and standard OCT logarithmic scale display. Enhanced vitreous imaging with SS-OCT may help assess the natural history and treatment response in vitreoretinal interface diseases.

Idiopathic vitreomacular traction and macular hole: a comprehensive review of pathophysiology, diagnosis, and treatment

Posterior vitreous detachment (PVD) is a common phenomenon in the aging eye. However, this may be complicated by persistent symptomatic vitreomacular adhesions that exert tractional forces on the macula (vitreomacular traction; VMT). VMT itself may be associated with epiretinal membrane formation and the development of idiopathic macular holes (IMH). Such pathologies may cause visual disturbances, including metamorphopsia, photopsia, blurred vision, and decreased visual acuity, which impact an individual's quality of life. Technologies such as optical coherence tomography allow an increasingly more accurate visualisation of the macular anatomy, including quantification of macular hole characteristics, and this facilitates treatment decision-making. Pars plana vitrectomy remains the primary treatment option for many patients with VMT or IMH; for the latter, peeling of the inner limiting membrane (ILM) of the retina has shown improved outcomes when compared with no ILM peeling. The development of narrow-gauge transconjunctival vitrectomy systems has improved the rate of visual recovery following surgery. Ocriplasmin, by degrading laminin and fibronectin at the vitreoretinal interface, may allow induction of PVD in a non-invasive manner. Indeed, clinical studies have supported its use as an alternative to surgery in certain patient populations. However, further research is still needed with respect to greater understanding of the pathophysiology underlying the development of VMT and IMH.