Inner Segment/outer Segment Research Articles

Visual Impact of Early Hydroxychloroquine-Related Retinal Structural Changes in Patients with Systemic Lupus Erythematosus

Purpose: The aim of the study was to assess the early retinal structural changes due to hydroxychloroquine (HCQ) use and its impact on visual acuity (VA) of patients with systemic lupus erythematosus (SLE). Patients and Methods: The study was conducted as a case-control study that included 60 eyes of 30 SLE patients treated with HCQ compared with 50 eyes of 25 healthy individuals. Patients were kept on 200 or 400 mg as daily maintenance dose. SLE patients were subgrouped into patients with normal VA and patients with decreased VA. All participants were assessed by the optical coherence tomography (OCT), and early structural abnormalities were recorded. The main outcomes and measures were best-corrected VA, drug exposure time, central macular thickness (CMT), inner segment-outer segment (IS-OS) junction disruption, ganglion cell complex † (GCC†, ganglion cell layer + inner plexiform layer), ganglion cell complex †† (GCC††, nerve fiber layer + GCC†), and peripapillary retinal nerve fiber layer. The characteristics of HCQ retinal toxicity were correlated to VA. Results: All OCT parameters were found to be significantly lower (p < 0.001) in HCQ patients with decreased VA than in controls. Patients receiving a daily dose of 400 mg had lower (p < 0.05) parameters than those receiving 200 mg. Patients with IS-OS disruption had lower CMT, GCC †, and GCC †† than those without (p < 0.05). VA was significantly correlated (p < 0.05) with CMT and drug exposure time. Conclusions: The HCQ use caused OCT changes that precede clinically visible retinopathy and might be associated with slight VA reduction. Screening with OCT of patients receiving HCQ is essential to detect early vision loss.

Association of Deep Retinal Capillary Plexus ischemia with Inner Segment/Outer Segment Disruption in Diabetic Macular Ischemia

ABSTRACT Background: Diabetic macular ischemia (DMI) is an important cause of visual impairment in patients with diabetic retinopathy. In some patients, it may lead to irreversible visual loss. Purpose: The aim of the work was to assess the presence of outer retinal structural changes at the level of inner segment /outer segment (IS/OS) in relation to macular capillary non-perfusion at the level of deep capillary plexus (DCP) in diabetic retinopathy (DR). Patients and Methods: A prospective observational study was carried on 250 eyes of 125 patients. They underwent scanning using Optical coherence tomography/ Optical coherence tomography angiography (OCT/OCTA) simultaneously. Results: 250 of 125 diabetic patients were classified according to presence of capillary non perfusion (NP), into two groups (ischemic- non ischemic). The incidence of DCP NP was 100% in eyes with DMI while the incidence of superficial capillary plexus (SCP) NP was 71% . The incidence of foveal avascular zone (FAZ) irregularity, inner segment /outer segment (IS/OS) disruption was 100% and 95% respectively among eyes with DMI. DCP NP was more than SCP NP in eyes with FAZ irregularity, which make it the possible main cause of the structural changes in the retina during ischemia. There was a strong association between the presence of IS/OS disruption with duration, severity of DR and BCVA. Conclusion: It could be concluded thatIS/OS disruption is associated with ischemia at DCP. It could be considered a reliable OCT findings that indicate an underling DMI and their presence can affect visual prognosis.

Retinal cross-section motion correction in three-dimensional retinal optical coherence tomography.

Motion correction is an important issue in ophthalmic optical coherence tomography (OCT), and can improve the ability of data sets to reflect the physiological structures of tissues and make visualization and subsequent analysis easier. In this study, we present a novel method to correct the cross-sectional motion artifacts in retinal OCT volumes. Motion along the x-direction (fast-scan direction) is corrected through the normalized cross-correlation algorithm, while axial motion compensation is performed using the polynomial fitting method on the inner segment/outer segment (IS/OS) layer segmented by the shortest path faster algorithm (SPFA). The results of volunteers with central serous chorioretinopathy demonstrate that the proposed method effectively corrects motion artifacts in OCT volumes and may have potential application value in the evaluation of ophthalmic diseases such as diabetic retinopathy, glaucoma and age-related macular degeneration.

Optical Coherence Tomography Angiography following Scleral Buckling Surgery.

The retinal changes following scleral buckling surgery (SBS) for rhegmatogenous retinal detachment (RRD) have been rarely evaluated with optical coherence tomography angiography (OCTA). A 40 years old male presented with subtotal RD involving the macula and had best corrected visual acuity of logmar 2.3 in the affected right eye. Five months after applying 120 degree scleral buckle, swept source optical coherence tomography (SSOCT) and swept source optical coherence tomography angiography (SS-OCTA) were done. At five months post-surgery, despite a settled retina in the operated eye, the patient had vision of logmar 1 and thin retinal nerve fibre layer (115 micrometer). The SSOCT showed inner segment-outer segment (IS-OS) junction disruption, thinned retinal pigment epithelium, central macular thickness of 275 micrometer and subfoveal choroidal thickness of 222 micrometer. A 3x3 mm macular OCTA scan showed a normal foveal avascular zone along with higher values for vascular density in superficial capillary plexus in all quadrants except temporal quadrant in operated eye as compared to fellow eye. The SBS with 120 degree buckle did not lead to a reduced vascular density in superficial capillary plexus in the operated eye with respect to fellow eye.

Optical Coherence Tomography (Angiography) Biomarkers in the Assessment and Monitoring of Diabetic Macular Edema.

Retinopathy is one of the most severe diabetes-related complications, and macular edema is the major cause of central vision loss in patients with diabetes mellitus. Significant progress has been made in recent years in optical coherence tomography and angiography technology. At the same time, various parameters have been attributed the role of biomarkers creating the frame for new monitoring and treatment strategies and offering new insights into the pathogenesis of diabetic retinopathy and diabetic macular edema. In this review, we gathered the results of studies that investigated various specific OCT (angiography) parameters in diabetic macular edema, such as central subfoveal thickness (CST), cube average thickness (CAT), cube volume (CV), choroidal thickness (CT), retinal nerve fiber layer (RNFL), retinal thickness at the fovea (RTF), subfoveal choroidal thickness (SFCT), central macular thickness (CMT), choroidal vascularity index (CVI), total macular volume (TMV), central choroid thickness (CCT), photoreceptor outer segment (PROS), perfused capillary density (PCD), foveal avascular zone (FAZ), subfoveal neuroretinal detachment (SND), hyperreflective foci (HF), disorganization of the inner retinal layers (DRIL), ellipsoid zone (EZ), inner segment/outer segment (IS/OS) junctions, vascular density (VD), deep capillary plexus (DCP), and superficial capillary plexus (SCP), in order to provide a synthesis of biomarkers that are currently used for the early diagnosis, assessment, monitoring, and outlining of prognosis.

IDENTIFICATION AND CLASSIFICATION OF MACULAR MORPHOLOGIC BIOMARKERS RELATED TO VISUAL ACUITY IN RADIATION MACULOPATHY: A Multimodal Imaging Study.

To identify and classify, by a multimodal imaging approach, the most relevant macular morphologic biomarkers related to visual acuity in patients affected by radiation maculopathy secondary to brachytherapy. Fifty-one consecutive patients previously treated with Iodine-125 brachytherapy because of uveal melanoma were enrolled. Each patient underwent full ophthalmologic examination including best-corrected visual acuity and multimodal macular imaging analysis. Macular morphological parameters were processed by a stepwise selection analysis. Three macular parameters were identified as the most relevant macular morphologic biomarkers of poor visual acuity: the vertical thickness of the thickest macular cyst (P = 0.0001), the presence of foveal inner segment/outer segment (IS/OS) layer disruption (P = 0.0054), and the presence of foveal retinal pigment epithelium atrophy (0.0884). The intergrader agreement for these morphologic biomarkers was 0.98, 0.92, and 0.92, respectively (interclass correlation coefficient). The vertical thickness of the thickest macular cyst, the presence of foveal retinal pigment epithelium atrophy, and IS/OS layer disruption can be used to clinically characterize radiation maculopathy. These parameters allow for separation of the edematous component of radiation maculopathy, which is potentially treatable in early disease stages, from late onset atrophic components, which are theoretically irreversible.

Changes of outer retinal thickness with increasing age in normal eyes

AIM: To comprehensively investigate the relationship between outer retinal layer thickness and age in normal eyes. METHODS: One hundred normal eyes of 100 subjects who underwent spectral-domain optical coherence tomography (SD-OCT) were included in this retrospective study. The distances between the external limiting membrane (ELM) line and the photoreceptor inner segment/outer segment (IS/OS) line (ELM-IS/OS), the IS/OS line and the cone outer segment tips (COST) line (IS/OS-COST), the COST line and the retinal pigment epithelium (RPE) complex (COST-RPE) and the full retinal thickness (RT) were measured at the fovea and on four quarters. The relationship between thickness and age or sex was then analysed. CONCLUSION: In normal eyes, the RT thickness on the nasal quarter and the ELM-IS/OS thickness were significantly and negatively correlated with age. The IS/OS-COST and COST-RPE thicknesses were not significantly correlated with age or sex.

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

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

Automated morphometric measurement of the retinal pigment epithelium complex and choriocapillaris using swept source OCT.

We report the development of an automated method to measure morphological features of the retinal pigment epithelium (RPE), Bruch's membrane (BM) and choriocapillaris (CC) using a commercially available swept source OCT (SS-OCT) system. The locations of the inner segment/outer segment (IS/OS), RPE and CC were determined by optical coherence tomography (OCT) and OCT angiography (OCTA) A-scan intensity profiles, which were used to calculate the mean IS/OS-to-RPE distance, mean RPE-to-CC distance, mean RPE-to-CC outer boundary distance, mean RPE thickness and mean CC thickness across the entire scan volume. The automated method was tested on two groups of normal subjects: younger age group (n=20, 30.3 ± 5.72 years, axial length = 24.2 ± 0.96 mm) and older age group (n=20, 80.8 ± 4.12 years, axial length = 23.5 ± 0.93 mm). The 6×6 mm macular scans were acquired from one eye of each subject. Repeatability of the measurements showed a coefficient of variance < 5% for all the cases. CC locations were confirmed qualitatively with pixel-by-pixel moving of the en face OCT/OCTA images. Relative distance and thickness maps of the RPE-BM-CC complex were generated for visualization of regional changes. We observed thinner CC, thinner RPE and increased RPE-to-CC distance in the older age group. Correlation between CC thickness and choroid thickness suggests that the CC thins with the overall thinning of the choroid. These metrics should be useful to reveal more morphological details of RPE-BM-CC complex, provide a better understanding of the CC in three dimensions, and further investigate potential functional relationships between RPE, BM and CC, and their involvement in age-related ocular diseases.

Identifying central serous chorioretinopathy biomarkers in coexisting diabetic retinopathy: a multimodal imaging study

BackgroundTo describe clinical and imaging characteristics of patients presenting with diabetic retinopathy (DR) with coexisting acute or chronic central serous chorioretinopathy (CSCR).MethodsThis was a cross-sectional study which included 54 eyes...

High-Resolution SD-OCT and EDI-OCT in the Evaluation and Management of Multifocal Serpiginoed Choroditis

Purpose To describe spectral domain optical coherence tomography (SD-OCT) and enhanced depth image OCT (EDI-OCT) findings of multifocal serpiginoid choroditis (MSC) , including affected layer of retinal involvement, changes at the vitreoretinal interface, and response to therapy. Methods A retrospective review of 20 eyes (14 patients) with MSC. Each patient underwent a complete ophthalmologic examination, fundus photography, fundus autoflorecence (FAF) and OCT imaging of the affected retina at the initial visit and on each follow-up. Results In acute stage, SD-OCT showed hyperreflective areas involving the outer retinal layers which include retinal pigment epithelium (RPE), photoreceptor outer segment tips (POST), inner segment–outer segment (IS/OS) junction, external limiting membrane (ELM), and outer nuclear layer (ONL) with choroidal and intraretinal layer cells infiltrate. EDI-OCT showed increase choroidal thickness. As the lesions began to heal, irregular, knobby elevations of outer retinal layers appeared (RPE, POST, IS/OS junction, and ELM could not be distinguished) with significant decrease in choroidal and intraretinal cells. On complete healing, loss of RPE, POST, IS/OS junction, and ELM in SD-OCT scan and absent of the choroidal and intraretinal cells and continous hyperreflactivity of the choroid (increased penetrance). Conclusion SD-OCT and EDI-OCT provides high-resolution detail regarding ultrastructural changes in vitreoretinal interface, outer retina and choroid during the course of the lesion. Serial SD-OCT and EDI-OCT also provides further insight into response to therapy by observing choroidal and intraretinal cells.

Short-term outcomes of combined pars plana vitrectomy for epiretinal membrane and phacoemulsification surgery with multifocal intraocular lens implantation.

PurposeThe purpose of this study was to evaluate the functional and anatomical outcomes of combined phacovitrectomy with multifocal intraocular lens (mfIOL) implantation.MethodsRetrospective, interventional, non-comparative case series of six eyes that received a combined phacoemulsification surgery with apodized, diffractive mfIOL implantation for cataract and pars plana vitrectomy (PPV) with membrane peeling for epiretinal membrane (ERM). Outcome measures included distance and near visual acuities (DVA and NVA), central macular thickness (CMT), intraocular pressure (IOP), and disruption of external limiting membrane (ELM) or inner-segment outer-segment (IS/OS) junction.ResultsMean logMAR glare DVA improved from 0.40 (Snellen 20/50) preoperatively to a mean uncorrected DVA of 0.038 (Snellen 20/22) (P=0.004) at 6 months after surgery. All eyes achieved NVA of J2 or better by 12 months postoperatively. Median CMT improved by 10 µm and mean IOP increased by 1 mmHg at 12 months postoperatively. Percentage of patients with ELM or IS/OS disruptions decreased from 66.7% to 33.3%. Two eyes demonstrated residual metamorphopsia on Amsler grid testing postoperatively. Postoperatively, four eyes required laser capsulotomy and one required LASEK for refractive correction.ConclusionCombined phacovitrectomy, membrane peeling, and mfIOL implantation improved VA in patients with idiopathic ERM. Multifocality was achieved, but final visual outcome was delayed due to posterior capsular opacification and macular healing.

Comparison of one and three initial monthly intravitreal ranibizumab injection in patients with macular edema secondary to branch retinal vein occlusion.

To compare three initial monthly intravitreal ranibizumab (IVR) injections followed by pro re nata (PRN) dosing with one initial monthly IVR injections followed by PRN dosing for macular edema (ME) secondary to branch retinal vein occlusion (BRVO). Forty-two eyes of 42 patients who had IVR injections for BRVO were retrospectively studied. Eighteen eyes received 1 initial IVR injection (1+PRN group) and 24 eyes received 3 monthly IVR injections (3+PRN). At 1, 3, 6 and 12mo; spectral-domain optical coherence tomography (SD-OCT) was performed. Central macular thickness (CMT), the integrity of the external limiting membrane (ELM), the presence of subretinal fluid, cyst size, the presence of inner segment/outer segment (IS/OS) defect were determined. At baseline the mean CMT was 521.3±153.2 µm in the 3+PRN group while it was 438.1±162.4 µm in 1+PRN group. At the final visit, mean CMT was 278.3±87.8 µm in the 3+PRN group and 285.2±74.2 µm in the 1+PRN group (P=0.079). The changes in CMT over the entire study period were also comparable in both groups (243±160 µm in the 3+PRN group, and 152.9±175.3 µm in the 1+PRN group; P=0.090). At baseline, best-corrected visual acuity (BCVA) was 0.92±0.60 logarithm of the minimal angle of resolution (logMAR) in the 3+PRN group, while it was 0.72±0.46 logMAR in the 1+PRN group. Final BCVA was 0.42±0.55 logMAR in the 3+PRN group and 0.38±0.50 logMAR in the 1+PRN group (P=0.979). Additionally, the BCVA changes from baseline to final visit were not significantly different (-0.50±0.45 logMAR in the 3+PRN group, and -0.33±0.39 logMAR in the 1+PRN group; P=0.255). No significant differences in the anatomical or functional results are found between 3+PRN and 1+PRN regimens in the patients receiving ranibizumab for ME secondary to BRVO. Intact IS/OS and baseline BCVA are good predictor of the visual gain, while baseline CMT is a good predictor of the anatomical gain.

Macular integrity assessment to determine the association between macular microstructure and functional parameters in diabetic macular edema.

To respectively evaluate macular morphological features and functional parameters by using spectral-domain optical coherence tomography (SD-OCT) and macular integrity assessment (MAIA) in patients with diabetic macular edema (DME). This prospective, non-controlled, open study included 61 eyes of 38 consecutive patients with DME. All patients underwent best-corrected visual acuity (BCVA) measurement, MAIA microperimetry, and SD-OCT. DME morphology, including central retinal thickness (CRT) and central retinal volume (CRV); integrity of the external limiting membrane (ELM) and photoreceptor inner segment/outer segment (IS/OS) junction; and the deposition of hard macular exudates were assessed within a 1000-µm central subfield area. MAIA microperimetry parameters evaluated were average threshold (AT)-retinal sensitivity, macular integrity index (MI), fixation points within a circle of radius 1° (P1) and 2° (P2), and bivariate contour ellipse area considering 63% and 95% of the fixation points (A63 and A95, respectively). MI was significantly higher in eyes with disrupted ELM or IS/OS, compared with eyes with intact ELM and IS/OS. Values of BCVA (logMAR), total AT, AT within 1000-µm diameter, P2, A63, A95, and CRT were significantly worse in eyes with disrupted IS/OS, compared with eyes with intact IS/OS. The values of BCVA (logMAR), AT within 1000-µm diameter, and CRT were significantly worse in eyes with disrupted ELM, compared with eyes with intact ELM. These parameters were not significantly different between eyes with or without hard macular exudate deposition. CRV was not significantly different in the presence or absence of the integrity of ELM, IS/OS, or deposition of hard macular exudates. At the center, nasal and temporal sectors of the fovea, significant negative correlations were observed between retinal thickness and AT of the corresponding area. At the inferior and superior sectors of the fovea, no correlations were observed between retinal thickness and AT of the corresponding area. In the intact IS/OS group, significant negative correlations were observed between CRT and central AT. There was no correlation between retinal sensitivity and thickness when the IS/OS layer was disrupted. Multiple linear regression analyses revealed that IS/OS integrity was an independent factor affecting MI. Functional (BCVA and visual field) and morphological parameters (retinal thickness) were significantly associated with an intact IS/OS. Local photoreceptor integrity was a strong predictor of local visual function throughout the retina. MI revealed the functional status in DME, reflecting the IS/OS juction status in the macula.

Demonstration of anatomical development of the human macula within the first 5years of life using handheld OCT.

To demonstrate the anatomical development of the human macula using handheld spectral domain optical coherence tomography (SD-OCT) during the first 5years of life. This study is a cross-sectional, observational case series. Thirty-five normal eyes of 35 full-term/late preterm infants and children under 5years of age were included. Handheld SD-OCT was used to image the macula of each eye. The data were analyzed using the Duke OCT Retinal Analysis Program v17 software. Retinal thickness maps were generated for the total retinal thickness (TRT), the inner retinal layers thickness (IRL), and the photoreceptor layer thickness (PRL). Based on the early treatment diabetic retinopathy study macular map, average thickness measurements were taken at 4 circles centered on the fovea (diameter): the foveal center (0.5mm), sector 1 (S1) (1mm), sector 2 (S2) (3mm), sector 3 (S3) (6mm). The median age at participation was 24months (range 5-52months). The TRT increased throughout the first 5years of life, and this increase was statistically significant at the foveal center and S1 (p = 0.01, p = 0.016, respectively). The IRL did not show any significant change in thickness from birth and throughout the first 5years of life. The PRL thickness showed thickening in the first 24months of age at the foveal center and S1 which was statistically significant at S1 (p = 0.066, p = 0.016, respectively). Interestingly, this PRL thickness increase plateaus beyond 24months of age. The photoreceptors inner segment/outer segment (IS/OS) band was identified as a distinct layer in all our subjects. Our findings conform with the literature that the anatomical development of the macular IRL completes before 5months of age and hence before the PRL. We also identify 24months of age as an important developmental milestone for photoreceptors development in the human macula.

Genetic Rescue Reverses Microglial Activation in Preclinical Models of Retinitis Pigmentosa.

Microglia cells (MGCs) play a key role in scavenging pathogens and phagocytosing cellular debris in the central nervous system and retina. Their activation, however, contributes to the progression of multiple degenerative diseases. Given the potential damage created by MGCs, it is important to better understand their mechanism of activation. Here, we explored the role of MGCs in the context of retinitis pigmentosa (RP) by using four independent preclinical mouse models. For therapeutic modeling, tamoxifen-inducible CreER was introduced to explore changes in MGCs when RP progression halted. The phenotypes of the MGCs were observed using live optical coherence tomography, live autofluorescence, and immunohistochemistry. We found that, regardless of genetic background, MGCs were activated in neurodegenerative conditions and migrated beyond the layers where they are typically found to the inner and outer segments, where degeneration was ongoing. Genetic rescue not only halted degeneration but also deactivated MGCs, regardless of whether the intervention occurred at the early, middle, or late stage of the disease. These findings suggest that halting long-term disease progression may be more successful by downregulating MGC activity while co-administering the therapeutic intervention.

The Correlation between Macular Ischemia by Fundus Fluorescein Angiography and Spectral Domain Optical Coherence Tomography Findings in Diabetic Macular Edema

AbstractBackground: To study the association between the OCT structural changes, and vascular changes around the fovea in FFA in the detection of ischemic diabetic maculopathy.Material and Methods: A 35 eyes of 25 patients with ischemic and mixed diabetic maculopathy were included as determined by irregular margins of the FAZ in fluorescein angiography. We measured the best-corrected visual acuity (BCVA), central macular thickness, inner retinal layer thickness and the lateral extent of inner segment-outer segment (IS-OS) disruption on SD-OCT images, as well as the FAZ to optic nerve head (FAZ/ONH) area ratio using the Image J program.Results: The central macular thickness and the inner retinal layer thickness showed no significant correlation with FAZ/ONH area ratio (p=0.161, 0.480 respectively). The mean horizontal and vertical extents of IS-OS disruption were not significantly correlated with FAZ/ONH area ratio (p=0.630 and p=0.732 respectively. The horizontal and vertical extents of IS-OS disruption showed a significant correlation with Log MAR BCVA (r=0.798 and 0.795 respectively, p<0.001 in both). The FAZ/ONH area ratio was positively correlated with LogMAR BCVA but was not statistically significant (p=0.815, r=–0.041).Conclusion: In patients with diabetic retinopathy, it is not possible to predict FAZ area based solely on the measure-ments assessing volume and thickness or retinal structure evaluation on OCT. Consequently, at present OCT cannot replace FA in the detection of ischemic or mixed diabetic maculopathy.

The relation between inner segment/outer segment junction and visual acuity before and after ranibizumab in diabetic macular edema

Purpose The aim of the study was to evaluate the relation between the photoreceptor inner segment/outer segment (IS/OS) junction integrity and the best corrected visual acuity (BCVA) and color vision after intravitreal injection of antivascular endothelial growth factor, ranibizumab in patients with diabetic macular edema (DME).Patients and methods This prospective observational interventional study was conducted on 50 eyes of patients with DME. All patients received three doses of intravitreal injection of antivascular endothelial growth factor (ranibizumab) 1 month apart. The photoreceptor IS/OS was evaluated by spectral domain optical coherence tomography and correlated to both BCVA and color vision by the Ishihara pseudoisochromatic 38 plates test.Results There was highly statistically significant improvement of photoreceptor IS/OS integrity after the second (P=0.003) and third injections (P=0.000). There were increases in the percentage of cases that read the color test correctly after each injection, but this increase was found to be not statistically significant when compared to color vision before the first injection. The mean BCVA was 0.96±0.09 SD (logarithm of the minimum angle of resolution) before the first injection. There was a highly statistically significant improvement in the BCVA after first (0.78±0.15), second (0.70±0.15), and third injections (0.64±0.16) (P=0.000). There was a statistically significant relation between color vision and IS/OS after the first injection (P=0.047), but it was a highly statistically significant relation after the second and third injections (P=0.000). BCVA was significantly related to IS/OS after the second and third injection (P=0.017 and 0.000, respectively).Conclusion The continuity of the foveal photoreceptor IS/OS layer evaluated by means of spectral domain optical coherence tomography is a valuble prognostic indicator of visual acuity and color vision outcome in patients with DME.

Half-Fluence Photodynamic Therapy for Chronic Central Serous Chorioretinopathy: Predisposing Factors for Visual Acuity Outcomes

ABSTRACTBackground: Central serous chorioretinopathy (CSC) is characterised by a serous detachment of the neurosensory retina in the macula. Chronic CSC tends to affect older individuals with a less favourable visual outcome. Photodynamic therapy (PDT) with verteporfin is a possible therapeutic approach in cases of CSC with no tendency for spontaneous resorption. PDT has shown good anatomic and functional results in treating chronic CSC. For the purpose of diminishing side effects, modifications of the standard protocol were used. Materials and Methods: This is a retrospective study of 32 eyes with CSC of 32 patients treated by half-fluence PDT. The patients underwent complete ophthalmology examination. On optical coherence tomography (OCT) we measured central retinal thickness (CRT), the outer nuclear layer (ONL), presence of subfoveolar detachment of retinal pigment epithelium (PED), disturbance of external limiting membrane (ELM), morphological changes in the inner segment/outer segment (IS/OS) line and retinal pigment epithelium (RPE) atrophy. We evaluated at baseline, 3 and 12 months after PDT. Results: The mean BCVA at baseline was 0.41 ± 0.23 log MAR, the mean BCVA at 3 months was 0.24 ± 0.20 and at the end of the follow-up it was 0.23 ± 0.200. We observed statistically significant improvements of visual acuity after 3 and 12 months (p < 0.001, Wilcoxon test). The mean central retinal thickness at baseline was 373 ± 87 µm, the mean CRT after 3 months was 234 ± 42 µm and after 12 months 223 ± 39 µm. A significant reduction from baseline was seen after 3 months and 12 months (p < 0.001, Wilcoxon test). Baseline ONL reached 80 ± 27 µm, after 3 months it was 78 ± 20 and after 12 months it was 74 ± 20 µm. We observed a statistically significant change in diminishing the amount of PED after PDT after 3 months and after 12 months (p = 0.021, McNemar’s test). We observed that in patients with RPE ablation, there is lower chance for the restitution of the IS/OS layer (p = 0.045, Mann–Whitney test). We observed a negative association between the improvement of visual acuity after 12 months and the presence of RPE ablation (p = 0.031, Mann–Whitney test). Restitution of ELM was significantly more often in patients with shorter duration of symptoms, (p = 0.027 after 3 months, p = 0.033 after 12 months after PDT, Spearman correlation). Neither ocular nor systemic adverse effects were observed during the follow-up period. Conclusions: Half-fluence PDT treatment has shown to be a usually safe and often effective therapy in patients with chronic CSC. This study suggests that the most important predictive factor is baseline visual acuity. The important anatomical change detected using OCT is a thinning of the outer nuclear layer. Nonetheless, other studies with a larger number of patients and a longer follow-up are required.

Clinical efficacy evaluation of vitrectomy combined with autologous internal limiting membrane transplantation for large macular hole

Background Giant idiopathic macular hole (IMH) severely affects visual acuity and increases operative difficulty during the surgery, so modifying or optimizing the operation method is helpful for improving the prognosis. Objective This study aimed to evaluate the efficacy and safty of vitrectomy combined with free internal limiting membrane transplantation for large IMH. Methods A prospective serial cases-observational study was carried out under the informed consent of each patient.Forty-two eyes of consecutive 42 patients with IMH of mean diameter (814.31±112.95)μm were included in the Second Hospital of Hebei Medical University from January 2013 to November 2015.All the eyes received vitrectomy combined with free internal limiting membrane transplantation and 12% C3F8 filling.The best corrected visual acuity (BCVA) (LogMAR), inner segment/outer segment (IS/OS) defect range, external limiting membrane defect range, retinal thickness at macular fovea were measured with slit lamp microscope, indirect ophthalmoscope and spectral-domain optical coherence tomography (SD-OCT) before surgery and 1, 3, 6 and 12 months after surgery. Results IMH complete closure in 97.6% eyes (41/44) at 12 months after surgery.BCVA was improved after operation and showed a significant difference among various time points (F=28.032, P<0.001). The IS/OS defect range was (1 112.00±45.44), (859.00±84.55), (649.00±52.47), (486.00±46.88) and (320.00±45.13)μm before surgery and 1, 3, 6 and 12 months after surgery, showing a significant difference among different time points (F=38.761, P<0.001), and the IS/OS defect range was gradually shrinked after operation compared with that before operation (all at P<0.05). The mean defect range of external limiting membrane was (1 038.00±39.63), (748.00±64.12), (585.00±48.88), (438.00±42.84) and (265.00±28.97)μm before surgery and 1, 3, 6 and 12 months after surgery, with a significant difference among various time points (F=36.459, P<0.001), and the mean defect range of external limiting membrane was evidently reduced (all at P<0.05). The foveal retinal thickness value was increased at 3, 6 and 12 months after surgery, which was significantly higher than that 1 month after surgery (all at P<0.05). The high reflect signal was faded away at 3 months after operation, indicating that implanted internal limiting membrane was decomposed and metabolized. Conclusions Vitrectomy combined with autologous internal limiting membrane transplantation seems to be safe and effective for large IMH. Key words: Retinal perforations/surgery; Macula; Vitrectomy; Basement membrane/surgery; Treatment outcome; Internal limiting membrane transplantation