Multimodal imaging of retinitis pigmentosa associated with Mainzer-Saldino syndrome

Background: Syndromic ciliopathies have been variably linked to different retinal dystrophies. However, to date, few reports have characterized by means of multimodal imaging the retinal degeneration occurring in Mainzer-Saldino syndrome (MSS).Methods: Two siblings with history of kidney disease and other systemic abnormalities presented at our eye clinic in October 2017 complaining of night blindness and visual loss. They underwent a complete ophthalmologic examination including visual acuity (VA) assessment, optical coherence tomography (OCT) and blue-light autofluorescence (BAF). A screen for inherited retinal dystrophies was performed in this occasion.Results: At baseline, the youngest sister had slightly worse VA (20/30 vs. 20/20-25 Snellen equivalents). On fundoscopy, both siblings had severe thinning of the peripheral retina, attenuation of retinal vessels and widespread accumulation of pigmented deposits. Significant outer retinal atrophy with apparent foveal sparing was appreciable on OCT.During the 3 years of follow-up, vision remained overall stable in both patients whereas minimal progression of outer retinal atrophy was observed by means of OCT. Genetic analysis revealed compound heterozygosity in the IFT172 gene. Based on these findings, a diagnosis of retinitis pigmentosa (RP) associated with MSS was formulated.Conclusions: Our report describes the cases of two siblings affected by retinitis pigmentosa associated with MSS. Although both carrying the same mutations and a severe RP phenotype, the youngest sister had slightly more advanced retinal degeneration highlighting the remarkable variability related to the IFT172 retinopathy.

Imaging Features Associated with Progression to Geographic Atrophy in Age-Related Macular Degeneration: Classification of Atrophy Meeting Report 5

PURPOSE

To provide an image-based description of retinal features associated with risk for development of geographic atrophy (GA) in eyes with age-related macular degeneration (AMD), as visualized with multimodal imaging anchored by structural OCT.

DESIGN

Consensus meeting.

PARTICIPANTS

International group that included those with expertise in imaging and AMD basic science and histology, and those with Reading Center experience in AMD clinical trials.

METHODS

As part of the Classification of Atrophy Meeting program, an international group of experts analyzed and discussed retinal multimodal imaging features in eyes with AMD associated with GA, risk of progression to GA, or both. Attendees undertook premeeting grading exercises that were reviewed during the meeting sessions. Meeting presentations illustrated established and investigational multimodal imaging features and associated histologic features. Each of these different features were then discussed openly by the entire group to arrive at consensus definitions. These definitions were applied to 40 additional images that were graded independently by attendees to refine the consensus definitions and descriptions further.

RESULTS

Consensus was reached on images with descriptors for 12 features. These features included components of outer retinal atrophy (e.g., ellipsoid zone disruption), components of complete retinal pigment epithelium (RPE) and outer retinal atrophy (e.g., RPE perturbation with associated hypotransmission or hypertransmission), features frequently seen in eyes with atrophy (e.g., refractile drusen), and features conferring risk for atrophy development (e.g., hyperreflective foci, drusen, and subretinal drusenoid deposits).

CONCLUSIONS

An international consensus on terms and descriptions was reached on multimodal imaging features associated GA and with risk for GA progression in eyes with AMD. We believe this information will be useful to clinicians who manage patients with AMD, researchers who study AMD disease interventions and pathogenesis, and those who design clinical trials for therapies targeting earlier AMD stages than GA expansion.

Neovascular Age-Related Macular Degeneration: Therapeutic Management and New-Upcoming Approaches

Age-related macular degeneration (AMD) constitutes a prevalent, chronic, and progressive retinal degenerative disease of the macula that affects elderly people and cause central vision impairment. Despite therapeutic advances in the management of neovascular AMD, none of the currently used treatments cures the disease or reverses its course. Medical treatment of neovascular AMD experienced a significant advance due to the introduction of vascular endothelial growth factor inhibitors (anti-VEGF), which dramatically changed the prognosis of the disease. However, although anti-VEGF therapy has become the standard treatment for neovascular AMD, many patients do not respond adequately to this therapy or experience a slow loss of efficacy of anti-VEGF agents after repeated administration. Additionally, current treatment with intravitreal anti-VEGF agents is associated with a significant treatment burden for patients, caregivers, and physicians. New approaches have been proposed for treating neovascular AMD. Among them, designed ankyrin repeat proteins (DARPins) seem to be as effective as monthly ranibizumab, but with greater durability, which may enhance patient compliance with needed injections.

Sutureless scleral fixation: comparison between 3-piece IOL and new single-piece foldable IOL

PURPOSE

Comparing two different sutureless scleral fixation techniques.

METHODS

A retrospective study of patients who underwent sutureless scleral fixation IOL from October 2013 to May 2018 at "Luigi Sacco Hospital", University of Milan. Comparison between two groups: Group 1 implanted with a 3-piece ALCON-MA60AC and group 2 implanted with a newly developed single-piece foldable IOL SOLEKO FIL-SSF. Patients underwent a complete preoperative ophthalmic assessment and post-operative evaluation at 1, 3, and 6 months. Vitrectomy was performed in all cases. The two groups were compared for age, axial length, and lens status at baseline. Visual acuity, refractive results, surgical time, and post-operative complications were recorded.

RESULTS

Thirty-one eyes were included: group 1, 15 eyes of 15 patients, and group 2, 16 eyes of 14 patients. No difference was found in visual acuity. Mean refractive error was 1D in both groups (group 1 1.01D, group 2 1.09D), but spherical equivalent was more often moved toward negative values and induced astigmatism was greater in the 3-piece group (group 1 1.91D [SD ± 2.07], group 2 0.67D [SD ± 0.88] P = 0.04). Surgical procedure was faster in group 2 (mean time difference 21', P = 0.01*). New displacement occurred in 5 cases (33%) of group 1 and in no cases of group 2 (P = 0.01*). Post-operative bleeding was registered only in group 1 (20%), but the difference was not statistically significant.

CONCLUSIONS

The group 2 IOL gives in our sample better results due to less post-operative astigmatism and reducing dislocation and bleeding during follow-up. Surgical technique appeared easier and faster: the specifically designed IOL seems to be a feasible solution for sutureless scleral fixation.

Retinal findings in patients with COVID-19: Results from the SERPICO-19 study

BACKGROUND

Coronavirus disease 2019 (COVID-19) has been associated to microvascular alterations. We screened the fundus of patients with COVID-19 to detect alterations of the retina and its vasculature and to assess possible correlations with clinical parameters.

METHODS

Cross-sectional study. The presence of retinal alterations in patients with COVID-19 and subjects unexposed to the virus was assessed using fundus photographs and their prevalence was compared. Mean arteries diameter (MAD) and mean veins diameter (MVD) were compared between patients and unexposed subjects with multiple linear regression including age, sex, ethnicity, body mass index, smoking/alcohol consumption, hypertension, hyperlipidaemia, diabetes as covariates. The influence of clinical/lab parameters on retinal findings was tested in COVID-19 patients.

FINDINGS

54 patients and 133 unexposed subjects were enrolled. Retinal findings in COVID-19 included: haemorrhages (9·25%), cotton wools spots (7·4%), dilated veins (27·7%), tortuous vessels (12·9%). Both MAD and MVD were higher in COVID-19 patients compared to unexposed subjects (98·3 ± 15·3 µm vs 91·9 ± 11·7 µm, p = 0.006 and 138·5 ± 21·5 µm vs 123·2 ± 13·0 µm, p<0.0001, respectively). In multiple regression accounting for covariates MVD was positively associated with COVID-19 both in severe (coefficient 30·3, CI95% 18·1-42·4) and non-severe (coefficient 10·3, CI95% 1·6-19·0) cases compared to unexposed subjects. In COVID-19 patients MVD was negatively correlated with the time from symptoms onset (coefficient -1·0, CI 95% -1·89 to -0·20) and positively correlated with disease severity (coefficient 22·0, CI 95% 5·2-38·9).

INTERPRETATION

COVID-19 can affect the retina. Retinal veins diameter seems directly correlated with the disease severity. Its assessment could have possible applications in the management of COVID-19.

FUNDING

None.

Comparison and Repeatability of High Resolution and High Speed Scans from Spectralis Optical Coherence Tomography Angiography

Purpose

The purpose of this study was to evaluate and compare the repeatability of optical coherence tomography angiography (OCTA) derived retinal vascular quantitative metrics using high resolution (HR) versus high speed (HS) acquisition modes.

Methods

Macular 4.4 × 2.9-mm OCTA images from normal, healthy volunteers were captured using both HR (768 A-scans × 256 B-scans) and HS (384 A-scans × 256 B-scans) acquisition protocols. Vessel density and vessel length density of the superficial capillary plexus and deep capillary plexus, as well as choriocapillaris flow deficit were computed. In a subset of eyes, the OCTA scans were repeated twice 2 days later and the same metrics were recomputed to assess repeatability, using intraclass correlation coefficients and coefficient of variation (CV).

Results

Comparison of measurements between HR and HS acquisitions in 41 healthy eyes showed statistically significant differences for all quantitative metrics (P < 0.01). However, no significant differences were observed among the three repeated scans (one on day 1 and two on day 3) obtained with each of the acquisition modes. The CVs ranged from 0.01 to 0.03 with the HR mode and 0.01 to 0.04 with the HS mode. The intraclass correlation coefficients (ICCs) among measurements were similar and high for both HR and HS modes, ranging from 0.844 to 0.949.

Conclusions

HR and HS OCTA acquisition modes both yielded repeatable quantitative metrics for the retinal circulation and the choriocapillaris. However, despite a similar field, the HR and HS derived measurements differed significantly.

Translational Relevance

To establish OCTA imaging in clinical and research practice, standardized and repeatability image analysis are necessary.

Impending Central Retinal Vein Occlusion in a Patient with Coronavirus Disease 2019 (COVID-19)

PURPOSE

To report a case of impending central retinal vein occlusion (iCRVO) in a COVID-19 patient.

CASE REPORT

A 54 years old woman with COVID-19 related pneumonia presented to our emergency department complaining of scotomas and decreased vision in her right eye. Funduscopic examination and multimodal imaging revealed rare retinal hemorrhages, retinal whitening, and fern-like hypo-autofluorescent appearance typical of iCRVO. She had no risk factors other than a transient hyper-coagulability status likely related to the ongoing infection. Systemic treatment with steroids normalized her inflammatory and coagulation status and the occlusion completely resolved.

CONCLUSIONS

Retinal circulation should be considered as a potential site for thromboembolic complications from COVID-19.

Peripheral exudative haemorrhagic chorioretinopathy: a widefield imaging study

AIMS

To study widefield imaging features, analyse risk factors for progression and compare treatment modalities of peripheral exudative haemorrhagic chorioretinopathy (PEHCR).

METHODS

Clinical and imaging data from each visit were collected, including near-infrared reflectance, fluorescein angiography, indocyanine green angiography, optical coherence tomography using the Spectralis platform (Heidelberg Engineering). Clinical features and treatment performed were recorded. Lesions were classified according to treatments used and according to the prognostic index of macular involvement (MI) and intravitreal bleeding (IVB).

RESULTS

50 eyes of 35 patients were retrospectively enrolled. Using widefield imaging, peripheral subretinal fluid (SRF) was detected in 31 (62%) eyes and peripheral neovascular networks were detected in 42 (84%) eyes and graded as focal, diffuse and subtotal in 22 (44%), 17 (34%) and 11 (22%) eyes, respectively. MI secondary to PEHCR during the follow-up was documented in 17 (34%) eyes, while IVB occurred in 7 (14%) eyes. Both MI and IVB correlated with peripheral SRF and lesion grade. Active treatment included anti-vascular endothelial growth factor (anti-VEGF) injections, photodynamic therapy (PDT) and combined anti-VEGF and PDT for 13 (26%), 1 (2%) and 18 (36%) eyes, respectively. In eyes with risk factors, anti-VEGF and combined treatment inversely correlated with MI incidence.

CONCLUSIONS

In our series, peripheral subretinal exudation and the extension of peripheral involvement represented risk factors for MI in eyes with PEHCR. In those high-risk eyes, active treatment is warranted.

Polypoidal Choroidal Vasculopathy: Consensus Nomenclature and Non-Indocyanine Green Angiograph Diagnostic Criteria from the Asia-Pacific Ocular Imaging Society PCV Workgroup

PURPOSE

To develop consensus terminology in the setting of polypoidal choroidal vasculopathy (PCV) and to develop and validate a set of diagnostic criteria not requiring indocyanine green angiography (ICGA) for differentiating PCV from typical neovascular age-related macular degeneration (nAMD) based on a combination of OCT and color fundus photography findings.

DESIGN

Evaluation of diagnostic test results.

PARTICIPANTS

Panel of retina specialists.

METHODS

As part of the Asia-Pacific Ocular Imaging Society, an international group of experts surveyed and discussed the published literature regarding the current nomenclature and lesion components for PCV, and proposed an updated consensus nomenclature that reflects our latest understanding based on imaging and histologic reports. The workgroup evaluated a set of diagnostic features based on OCT images and color fundus photographs for PCV that may distinguish it from typical nAMD and assessed the performance of individual and combinations of these non-ICGA features, aiming to propose a new set of diagnostic criteria that does not require the use of ICGA. The final recommendation was validated in 80 eyes from 2 additional cohorts.

MAIN OUTCOME MEASURES

Consensus nomenclature system for PCV lesion components and non-ICGA-based criteria to differentiate PCV from typical nAMD.

RESULTS

The workgroup recommended the terms polypoidal lesion and branching neovascular network for the 2 key lesion components in PCV. For the diagnosis of PCV, the combination of 3 OCT-based major criteria (sub-retinal pigment epithelium [RPE] ring-like lesion, en face OCT complex RPE elevation, and sharp-peaked PED) achieved an area under the receiver operating characteristic curve of 0.90. Validation of this new scheme in a separate subset 80 eyes achieved an accuracy of 82%.

CONCLUSIONS

We propose updated terminology for PCV lesion components that better reflects the nature of these lesions and is based on international consensus. A set of practical diagnostic criteria applied easily to spectral-domain OCT results can be used for diagnosing PCV with high accuracy in clinical settings in which ICGA is not performed routinely.

The In Vivo Correlation between Retinal Pigment Epithelium Thickness and Quantitative Fundus Autofluorescence in a White Population

PURPOSE

To investigate the influence of age on the thickness of the retinal pigment epithelium (RPE)/Bruch's membrane (BM) complex and the quantitative autofluorescence (qAF) and to study the possible correlation existing between these 2 parameters in a healthy White population.

DESIGN

Cross-sectional, observational study.

PARTICIPANTS

Healthy White volunteers aged 18 to 65 years.

METHODS

All subjects underwent spectral domain OCT (SD-OCT) and qAF imaging with the Heidelberg HRA-Spectralis (Heidelberg Engineering, Heidelberg, Germany). Spectral domain OCT images were analyzed using the in-built graph-based automatic segmentation algorithm for single retinal layer identification to assess RPE/BM complex thickness in vivo. The thickness values of both inner and outer rings of the Early Treatment Diabetic Retinopathy Study (ETDRS) grid, generated by the software using the "RPE" segmentation, were averaged to obtain a single RPE/BM complex thickness value in each eye. Quantitative autofluorescence images were also evaluated using a dedicated software. The qAF values of 8 subfields forming a ring centered onto the fovea were collected and averaged to obtain a single qAF value (qAF₈) in each eye. The correlation among the RPE/BM complex thickness, the qAF value, and the age of the subjects was investigated.

MAIN OUTCOME MEASURES

The in vivo correlation between RPE/BM complex thickness and qAF.

RESULTS

A total of 105 eyes from 105 subjects (mean age, 42.1 ± 13.9 years; range, 18-65) were included in the analysis. The mean RPE/BM complex thickness significantly increased with age (r = 0.33, P = 0.0006). The values of qAF also positively increased with age (P < 0.0001). A significant correlation was found between qAF and RPE/BM complex thickness (r = 0.27, P = 0.004). After adjusting for age, iris color, and gender, the correlation remained significant only for subjects aged less than 40 years (P = 0.009).

CONCLUSIONS

BM complex thickness was significantly co/BM complex thickness increased with age in a healthy White population. A similar increase was found for qAF values. After adjusting for age and iris color, qAF and RPE/BM complex thickness were still correlated in subjects aged less than 40 years. The RPE/BM complex thickness could reflect the lipofuscin/melanolipofuscin accumulation in normal subjects, adding great interest in RPE cell biology.

Fundus autofluorescence imaging

Fundus autofluorescence (FAF) imaging is an in vivo imaging method that allows for topographic mapping of naturally or pathologically occurring intrinsic fluorophores of the ocular fundus. The dominant sources are fluorophores accumulating as lipofuscin in lysosomal storage bodies in postmitotic retinal pigment epithelium cells as well as other fluorophores that may occur with disease in the outer retina and subretinal space. Photopigments of the photoreceptor outer segments as well as macular pigment and melanin at the fovea and parafovea may act as filters of the excitation light. FAF imaging has been shown to be useful with regard to understanding of pathophysiological mechanisms, diagnostics, phenotype-genotype correlation, identification of prognostic markers for disease progression, and novel outcome parameters to assess efficacy of interventional strategies in chorio-retinal diseases. More recently, the spectrum of FAF imaging has been expanded with increasing use of green in addition to blue FAF, introduction of spectrally-resolved FAF, near-infrared FAF, quantitative FAF imaging and fluorescence life time imaging (FLIO). This article gives an overview of basic principles, FAF findings in various retinal diseases and an update on recent developments.

Dexamethasone implants in patients with diabetic macular edema undergoing cataract surgery: Italian expert panel consensus statements

PURPOSE

Intravitreal corticosteroid implants based on sustained-release dexamethasone provide effective retinal delivery of drug for around 6 months for the treatment of diabetic macular edema (DME). As current recommendations on the management of patients with DME undergoing cataract surgery are limited, this article aims to highlight issues and provide guidance on the use of dexamethasone intravitreal implants (DEX-DDS) in patients with DME undergoing cataract surgery, based on the consensus findings of a panel of Italian experts.

METHODS

The panel developed a survey regarding the use of DEX-DDS in patients with DME undergoing cataract surgery, following a comprehensive literature search. The results of the survey were discussed at an experts' meeting in September 2018, with a structured approach to determining consensus. The routine management of patients with DME undergoing cataract surgery was also developed for use as a basis of discussion to highlight current issues.

RESULTS

Eight consensus statements are presented, along with key issues that highlight controversial/outstanding issues in the use of DEX-DDS in DME patients with cataracts.

CONCLUSION

The consensus statements can help provide practical guidance for clinicians in daily practice on the rationale, patient diagnosis and selection, and optimal management of patients with DME undergoing cataract surgery.

Optical coherence tomography angiography for detection of macular neovascularization associated with atrophy in age-related macular degeneration

PURPOSE

To evaluate the ability of optical coherence tomography angiography (OCTA) to detect macular neovascularization (MNV) in eyes with atrophy compared with fluorescein angiography (FA), indocyanine green angiography (ICGA), and optical coherence tomography (OCT).

METHODS

In this prospective study, eyes with MNV and atrophy (termed macular atrophy or MA) secondary to age-related macular degeneration (AMD), and AMD eyes with geographic atrophy (GA) without MNV underwent multimodal imaging with FA, ICGA, structural OCT, and OCTA. The presence of MNV was determined using all imaging modalities by senior retina specialists and was considered the gold standard reference. Each individual imaging modality was then evaluated independently by two expert readers for the presence of MNV in a masked fashion. Morphologic characteristics of the MNV were evaluated on the custom OCTA slab.

RESULTS

Twenty-one patients with MA+MNV and 21 with GA only were enrolled. Manual segmentation on OCTA allowed detection of the MNV in 95.2% of eyes with MA+MNV and in 4.7% of eyes with GA, showing high specificity (95.2%) and sensitivity (95.2%). FA, ICGA, and OCT detected MNV in 57.1%, 52.3%, and 66.7% of eyes with MA+MNV and in 14.2%, 9.5%, and 42.8% with GA. Sensitivity and specificity were 85.7% and 57.1% for FA, 90.5% and 52.4% for ICGA, and 66.7% and 57.1% for OCT.

CONCLUSIONS

OCTA appears to be superior to other imaging modalities for identification of MNV in eyes with macular atrophy. OCTA should be considered as part of the multimodal imaging evaluation of eyes with atrophy, particularly in the context of clinical trials.

Definition of indicators of appropriateness in the management of neovascular age-related macular degeneration: An expert opinion

Wet age-related macular degeneration is a chronic condition culminating, in most cases, in blindness. The introduction of anti-angiogenic agents in 2006 has represented a major breakthrough in the treatment of the disease, but timely and effective treatment with regular follow-up and monitoring is mandatory to stabilize and preserve visual acuity. In clinical practice, however, appropriate therapy provision is frequently challenged by economic and organizational issues that result in suboptimal visual outcomes and increased incidence of legal blindness. International Guidelines have defined a diagnostic and therapeutic pathway to ensure the best practice in wet age-related macular degeneration management, but reference parameters to evaluate and compare the performance of Retina Centers are lacking. To address the appropriateness of wet age-related macular degeneration management in Italy, a multidisciplinary panel of ten experts gathered in three meetings. They defined three sets of indicators and relative benchmark values that each Center should comply with to ensure patients optimal care already from the first access: (a) clinical intervention indicators, to determine the possible Center’s deviation from the diagnostic and therapeutic pathway; (b) outcome indicator, to evaluate the socioeconomic impact of the healthcare systems’ performance; (c) management indicators, to test the size of the gap between the Center’s supply and demand. Once the indicators have been analyzed, healthcare systems can plan actions to improve appropriateness and monitor their effects. However, to put this in practice, a concerted effort by all parts involved in healthcare provision is required, together with adequate systems to analyze clinical and administrative documentation.

Microaneurysms visualisation using five different optical coherence tomography angiography devices compared to fluorescein angiography

Background

To compare fluorescein angiography (FA) and five different optical coherence tomography angiography (OCTA) devices and to test their reproducibility in the evaluation of retinal microaneurysms (MAs) secondary to diabetic retinopathy (DR).

Methods

On the same day, patients with DR were imaged with FA and five OCTA devices: prototype Spectralis OCTA, prototype PlexElite, RTVue XR Avanti, AngioPlex and DRI OCT Triton. For all OCTA devices, a 3×3 volume scan pattern was performed. MAs were evaluated for the superficial capillary plexus (SCP) and deep capillary plexus (DCP).

Results

Twenty eyes of 15 patients with DR were included. FA counted a significantly higher number of MAs compared to OCTA devices. Spectralis OCTA obtained a significantly higher number of MAs compared to PlexElite, RTVue XR Avanti, AngioPlex and DRI OCT Triton (p<0.0001). PlexElite and AngioPlex showed a greater number of MAs in the SCP, Spectralis OCTA, RTVue XR Avanti and DRI OCT Triton in the DCP. Higher sensitivity (43.3%) but lowest specificity (54.4%) was observed for Spectralis OCTA compared to other devices. The higher specificity (78.5%) and positive predictive value (83.3%) were observed for DRI OCT Triton.

Conclusions

FA remains the best imaging modality to visualise retinal MAs. Spectralis OCTA was able to detect more MAs compared to other devices, likely due to the higher number of B-scans in the scanned area as well as due to the higher number of repeated B-scans. The high variability between OCTA devices should be taken into account for future clinical trials as in clinical practice.

Intravitreal aflibercept for management of choroidal neovascularization secondary to angioid streaks : The Italian EYLEA-STRIE study

PURPOSE

To investigate the effect and the safety of intravitreal aflibercept in patients affected by choroidal neovascularization secondary to angioid streaks with a long-term follow-up.

METHODS

Multicentre, open-label, phase IIb study (EYLEA-STRIE, EudraCT Number 2014-000986-30) involving four Italian centres (IRCCS Ospedale San Raffaele (Milano), Fondazione G.B. Bietti (Roma), Policlinico (Milano), Ospedale Luigi Sacco (Milano)). Patients with active choroidal neovascularization secondary to angioid streaks with foveal involvement were prospectively enrolled and followed for 18 months. All the patients received intravitreal 2 mg/0.05 mL aflibercept at the time of enrolment, followed by a pro-re-nata regimen for 48 weeks. Best-corrected visual acuity and central macular thickness were measured monthly. Adverse events were monitored at each visit.

RESULTS

Twenty-three eyes of 20 patients were analysed. Mean number of injections per patient was 4.30 ± 1.2. At week 48, the best-corrected visual acuity was 0.42 ± 0.40 LogMAR (p = 0.6 from baseline) and 18 eyes (81.8%) featured stability within 15 letters. The central macular thickness significantly reduced (p = 0.03). Eleven ocular non-serious adverse events and two serious adverse events were observed (one case of endophthalmitis and one case of acute gastritis were reported).

CONCLUSION

Intravitreal aflibercept represents a valid option for the management of choroidal neovascularization complicating angioid streaks. Further studies with longer follow-up and different therapeutic regimens are warranted to ascertain the best control of the disease.

Thresholding strategies to measure vessel density by optical coherence tomography angiography

OBJECTIVE

A variety of binarization strategies have been used to measure vessel density by optical coherence tomography angiography (OCT-A), but it is uncertain if they produce similar results. The purpose of the study was to evaluate the impact of different thresholding methods and contrast and brightness adjustment on OCT-A vessel density metrics.

DESIGN

Observational, cross-sectional case series.

PARTICIPANTS

Consecutive healthy volunteers.

METHODS

Healthy volunteers underwent fovea-centred 3 mm × 3 mm OCT-A scans using PlexElite 9000. Images of the superficial vascular plexus were generated using the instrument's automated segmentation. Images were thresholded with 5 different threshold tools in ImageJ (Default, Huang, IsoDat, Mean, and Otsu), and the threshold grey level value defined by each method was recorded. Brightness and contrast were also increased or decreased by 50% compared with the default. Binarization was performed using the threshold values from each method, and vessel densities were computed and compared.

MAIN OUTCOME MEASURES

Superficial plexus vessel density was measured and compared using different adjust threshold tools and changing brightness and contrast.

RESULTS

Twenty eyes of 20 healthy participants were included. Different threshold strategies produced measurements with different mean values (p < 0.0001). Pairwise comparisons revealed differences between all groups (p < 0.0001) except between the IsoData and Otsu thresholding approaches (p > 0.270). Increasing or decreasing the brightness or to 50% of the mean value also yielded statistically significant differences (p < 0.0001).

CONCLUSIONS

The method of thresholding and adjustments in contrast and brightness can significantly impact retinal vessel density measurements. These findings highlight the importance of using consistent thresholding strategies for clinical studies.

Sensitivity and Specificity of Multimodal Imaging in Characterizing Drusen

PURPOSE

To calculate the measures of accuracy of different imaging modalities in patients with early/intermediate age-related macular degeneration (AMD).

DESIGN

Prospective, observational, cross-sectional study.

PARTICIPANTS

Patients with early or intermediate AMD.

METHODS

All participants underwent a complete multimodal imaging assessment with a confocal scanning laser ophthalmoscope, including near-infrared reflectance (NIR), green fundus autofluorescence (G-FAF), confocal pseudocolor, and retromode deviated to right (DR) and left (DL). Drusen were topographically divided as small and medium (≤125 μ diameter) and large (>125 μ diameter), whereas subretinal drusenoid deposits (SDDs) were divided into dot and ribbon phenotypes. Multimodal imaging was considered the reference standard for detecting different subtypes of drusen and SDDs. Cohen's kappa (k) was used to test interobserver agreement for each imaging modality.

MAIN OUTCOME MEASURES

Capability to differentiate subtypes of drusen and SDDs with different imaging modalities.

RESULTS

A total of 100 eyes (62% were female participants) were evaluated. The inter-rate reliability between 2 readers for each imaging modality ranged between 0.76 and 0.95. Overall, large drusen were better identified with confocal pseudocolor imaging (96.6% sensitivity; 77.8% specificity). Smaller drusen were better detected with retromode modalities DR or DL (92% sensitivity; 58.3% specificity and 85.2% sensitivity; 83.3% specificity, respectively). Ribbon SDDs were better detected by color imaging (80.5% sensitivity; 98.3% specificity). Dot SDDs were well identified with NIR (83.1% sensitivity; 91.4% specificity) and G-FAF (84.6% sensitivity; 77.1% specificity).

CONCLUSIONS

Near-infrared reflectance and G-FAF should be considered for classification of dot SDDs, and confocal pseudocolor is optimal for characterizing ribbon SDDs. Among all imaging modalities, retromode technology DR and DL may be a potential supplementary modality to detect even smaller drusen.

Optical coherence tomography-based consensus definition for lamellar macular hole

BACKGROUND

A consensus on an optical coherence tomography definition of lamellar macular hole (LMH) and similar conditions is needed.

METHODS

The panel reviewed relevant peer-reviewed literature to reach an accord on LMH definition and to differentiate LMH from other similar conditions.

RESULTS

The panel reached a consensus on the definition of three clinical entities: LMH, epiretinal membrane (ERM) foveoschisis and macular pseudohole (MPH). LMH definition is based on three mandatory criteria and three optional anatomical features. The three mandatory criteria are the presence of irregular foveal contour, the presence of a foveal cavity with undermined edges and the apparent loss of foveal tissue. Optional anatomical features include the presence of epiretinal proliferation, the presence of a central foveal bump and the disruption of the ellipsoid zone. ERM foveoschisis definition is based on two mandatory criteria: the presence of ERM and the presence of schisis at the level of Henle's fibre layer. Three optional anatomical features can also be present: the presence of microcystoid spaces in the inner nuclear layer (INL), an increase of retinal thickness and the presence of retinal wrinkling. MPH definition is based on three mandatory criteria and two optional anatomical features. Mandatory criteria include the presence of a foveal sparing ERM, the presence of a steepened foveal profile and an increased central retinal thickness. Optional anatomical features are the presence of microcystoid spaces in the INL and a normal retinal thickness.

CONCLUSIONS

The use of the proposed definitions may provide uniform language for clinicians and future research.

Large Idiopathic Macular Hole Surgery: Remodelling of Outer Retinal Layers after Traditional Internal Limiting Membrane Peeling or Inverted Flap Technique

OBJECTIVE

To investigate the influence of the inverted flap technique compared with traditional internal limiting membrane (ILM) peeling in the postoperative remodelling of outer retinal layers of idiopathic macular holes (MHs) >450 µm.

METHODS

We analyzed medical records and imaging studies of all patients with an idiopathic MH >450 µm who underwent vitrectomy at the Sacco University Hospital, Milan, and the Sacro Cuore Don Calabria Hospital, Verona, Italy, between January 2008 and December 2017. Out of 41 eyes evaluated, 17 were treated with traditional ILM peeling and 24 with the inverted ILM flap technique. All patients underwent follow-up examinations every 3 months and all of them completed a final visit 12 months after surgery. Best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) parameters were evaluated at each visit. The main outcome measures were the postoperative recovery rate of the external limiting membrane (ELM) and ellipsoid zone (EZ), and postoperative BCVA. Correlations between OCT measurements and visual outcome were analyzed.

RESULTS

The ELM recovery rate in the ILM peeling group (15/17 eyes, 88%) was higher than in the ILM flap group (14/24 eyes, 58%) (p = 0.079). The EZ recovery rate was similar in the 2 groups, 7/17 eyes (41%) in the ILM peeling and 8/24 eyes (33%) in the ILM flap group (p = 0.744). Eyes without a persistent hyper-reflective "plug" at the edges of the MH showed a significantly higher EZ recovery rate (11/18, 61%) compared with eyes showing a persistent plug (4/23, 17%) (p = 0.008). The mean BCVA improved significantly in both groups: from 0.93 logMAR (20/170) to 0.26 logMAR (20/36) in the ILM peeling and from 0.98 logMAR (20/190) to 0.37 logMAR (20/46) in the ILM flap group. The final BCVA tended to be better in the ILM peeling group (p = 0.085).

CONCLUSIONS

Given the limited information about the influence of ILM flap versus traditional ILM peeling in the postoperative remodelling of large idiopathic MHs, our data provides some new insights into the healing process of MHs >450 µm. This should be considered as part of the decision process about whether to perform an ILM flap in these patients.

Functional versus functional and anatomical criteria-guided ranibizumab treatment in patients with neovascular age-related macular degeneration - results from the randomized, phase IIIb OCTAVE study

Background

To evaluate the efficacy and safety of two individualized ranibizumab retreatment schemes in neovascular age-related macular degeneration.

Methods

Patients (N = 671) were randomized (1:1) to receive three initial monthly ranibizumab 0.5 mg injections, then retreatment guided by either best-corrected visual acuity (BCVA) loss (Group I) or BCVA loss and/or signs of disease activity on optical coherence tomography (OCT; Group II). The study was terminated prematurely and the decision to discontinue the study was made by the sponsor. Efficacy analyses were performed on patients who completed 12 months of the originally planned 24-month study. Safety analyses are presented for all safety analyzable patients.

Results

Of 671 randomized patients, 305 completed 12 months of the study. For the 12-month completers, baseline mean (standard deviation) BCVA and reading-center evaluated central subfield thickness (CSFT) were comparable [Group I: 60.9 (13.10) letters and 517.7(201.79) μm; Group II: 60.2 (12.21) letters and 515.3 (198.37) μm]. The change from baseline at Month 12 in BCVA was 6.7 (13.48) letters in Group I and 8.3 (13.53) letters in Group II and the change in CSFT was − 161.3 (163.48) μm and − 175.3 (170.45) μm, respectively. The mean number of ranibizumab injections was 8.2 in Group I and 8.4 in Group II.

Conclusion

Ranibizumab treatment resulted in visual and anatomic gains at 12 months for both retreatment strategies, with a trend in favor of OCT-guided vs BCVA loss guided retreatment. No new safety signals were seen.

Trial registration

www.ClinicalTrials.gov (NCT01780935). Registered 31 January 2013.