Optical Coherence Tomography Scans Research Articles

Structural correlations between brain magnetic resonance image-derived phenotypes and retinal neuroanatomy.

The eye is a well-established model of brain structure and function, yet region-specific structural correlations between the retina and the brain remain underexplored. Therefore, we aim to explore and describe the relationships between the retinal layer thicknesses and brain magnetic resonance image (MRI)-derived phenotypes in UK Biobank. Participants with both quality-controlled optical coherence tomography (OCT) and brain MRI were included in this study. Retinal sublayer thicknesses and total macular thickness were derived from OCT scans. Brain image-derived phenotypes (IDPs) of 153 cortical and subcortical regions were processed from MRI scans. We utilized multivariable linear regression models to examine the association between retinal thickness and brain regional volumes. All analyses were corrected for multiple testing and adjusted for confounders. Data from 6446 participants were included in this study. We identified significant associations between volumetric brain MRI measures of subregions in the occipital lobe (intracalcarine cortex), parietal lobe (postcentral gyrus), cerebellum (lobules VI, VIIb, VIIIa, VIIIb, and IX), and deep brain structures (thalamus, hippocampus, caudate, putamen, pallidum, and accumbens) and the thickness of the innermost retinal sublayers and total macular thickness (all p < 3.3 × 10-5). We did not observe statistically significant associations between brain IDPs and the thickness of the outer retinal sublayers. Thinner inner and total retinal thicknesses are associated with smaller volumes of specific brain regions. Notably, these relationships extend beyond anatomically established retina-brain connections.

Clinical and Optical Coherence Tomography Features of Subretinal Fibrin Glue after Glue-Assisted Vitrectomy for Rhegmatogenous Retinal Detachment Repair. GUARD Study – Report 3:

Purpose: To highlight the clinical and optical coherence tomography (OCT) features of subretinal fibrin glue and its resolution over time in patients who have undergone glue- assisted retinopexy for Rhegmatogenous Retinal Detachments (RRD). Methods: A report of 2 cases with subretinal migration of fibrin glue. Both the cases were assessed with clinical examination, serial fundus photos and serial OCT scans through the area of subretinal fibrin immediately after surgery, at 1 week, 2 weeks and at 6 weeks. Results: In both the cases of intraoperative subretinal glue migration during glue-assisted vitrectomy for RRD repair, the subretinal glue had a characteristic appearance and course of evolution. On examination and color photography, the glue had an amorphous whitish appearance with wispy edges. This corresponded to subretinal hyperreflective material (SHRM) on OCT with a layered appearance. By two weeks after surgery, the subretinal glue demonstrated substantial regression on retinal examination and on OCT scans. At 6 weeks visit, the entire glue was noted to be resorbed along with an intact photoreceptor outer segments/Ellipsoid Zone layer Conclusion: In summary, this report describes the clinical and OCT appearance of subretinal migration of fibrin glue. Subretinal fibrin appears whitish on examination and corresponds to layered SHRM without shadowing on OCT. It appears to resorb spontaneously within weeks with apparent recovery of the overlying photoreceptors.

The association of symptomatic vitreous floaters with depression and anxiety.

To evaluate the levels of anxiety and depression in patients with symptomatic vitreous floaters and to determine the possible correlations of psychological implications with the symptoms duration and possible improvement, the degree of posterior vitreous detachment, and the discomfort severity. Ninety patients complaining for floaters and fifty-seven age- and gender-matched healthy-control subjects were recruited. Every participant underwent a complete ophthalmological examination, including funduscopy and optical coherence tomography scans, while clinical and demographic data were also gathered. The Patient Health Questionnaire-9 (PHQ-9), the Zung Depression Inventory-Self-Rating Depression Scale (Zung SDS), and the Hospital Anxiety and Depression Scale (HADS) were completed by everyone. Between the studied groups, no significant differences were detected regarding the clinical and demographic data (p > 0.05). The patients with floaters had significantly higher scores of PHQ-9, Zung SDS, HADS Anxiety, and HADS Depression (p < 0.001). After adjustment for several confounders, PHQ-9 (p = 0.041), Zung SDS (p = 0.003), and HADS Anxiety (p = 0.036) values remained significantly impaired. Among the patients, PHQ-9 and Zung SDS scores were significantly elevated in the patients with floaters duration less than 4weeks (p < 0.05). Finally, anxiety and depression were significantly correlated with the symptoms duration and intensity, with the floater-associated discomfort, and with the stage of posterior vitreous detachment. Vitreous floaters have a negative impact on patients' psychological status, by the terms of enhanced depressive and anxiety levels. To the best of our knowledge, our study is the first in the literature to elaborate the aforementioned association, by assessing three different questionnaires simultaneously.

Impact of treat and extend criteria on proportions that can be extended after loading phase of 2 mg aflibercept therapy for neovascular age related macular degeneration: PRECISE Report 5.

To study the impact of definitions of various treatment extension criteria on the proportion of patients who could be extended at their first visit after the loading phase of 2 mg aflibercept therapy for neovascular age related macular degeneration (nAMD). Patients with nAMD initiated on the loading phase of three intravitreal doses of 2 mg aflibercept in routine clinical practice were recruited from December 2019 to August 2021. The response to the loading phase was assessed at approximately 8 weeks post-loading (up to 140 days from first injection) based on different definitions of response. The proportion of patients that qualify for interval extension based on different clinical trial criteria was also evaluated. A total of 722 patients with visual acuity (VA) and optical coherence tomography (OCT) scans done at all 4 visits were included. Of these 32.4% of eyes responded with complete macular fluid resolution after the first injection with no recurrence through the loading phase (super-responders) while 26.9% had persistent macular fluid in all 4 visits (true non-responders). The rest were considered suboptimal responders. Change in VA showed marked variations within each of these categories of fluid resolution. For extension of next treatment interval, if presence of any macular fluid at the post-loading visit is the only criteria considered, about 50% could be extended to 8 weeks. If both VA worsening by ≥5 letters and a > 25 μm increase in central sub-field thickness (CST)are considered, 90% will be eligible for interval extension. Clinical trial designs and pre-defined treatment extension/shortening criteria determine the proportion of patients requiring treatment in the post-loading visit. The short and long-term impact of interval extension immediate post-loading on visual outcome in clinical practice is unknown.

Unveiling Key Pathological Indicators for Disease Progression in Vogt Koyanagi Harada Disease and Sympathetic Ophthalmia Through Advanced Choroidal Volume Analysis

ABSTRACT Purpose To evaluate the association between quantitative parameters derived from volume analysis of optical coherence tomography (OCT) data and disease worsening in Vogt-Koyanagi-Harada disease (VKHD) and sympathetic ophthalmia (SO). Methods This retrospective study, conducted at Osaka University Hospital, employed swept-source OCT scans from patients diagnosed with VKHD or SO between October 2012 and January 2021. The choroidal vessel structure was segmented and visualized in three dimensions, generating quantitative vessel volume maps. Region-specific choroidal vessel volume (CVV), choroidal volume (CV), and vessel index (VI) were scrutinized for their potential correlation with disease severity. Results Thirty-five eyes of 18 VKHD and 2 SO patient (8 females, 10 males) were evaluated. OCT-derived CVV maps revealed regional CV alterations in VKHD and SO patients. Two parameters, i.e. CV at 3- and 6-month follow-ups (p = 0.044, p = 0.040, respectively, with area under the ROC curve of 0.70) and CVV at 6 months (p = 0.046, area under the ROC curve of 0.71), were significantly higher in recurrent VKHD and SO compared to effectively treated cases. Conclusions The volume analysis of OCT images facilitates a three-dimensional visualization of choroidal alterations, which may serve as a reflection of disease severity in VKHD and SO patients. Furthermore, noninvasive initial CVV or CV measurements may serve as potential biomarkers for predicting disease recurrence in VKHD and SO.

Progression or Aging? A Deep Learning Approach for Distinguishing Glaucoma Progression from Age-Related Changes in OCT scans

To develop deep learning (DL) algorithm to detect glaucoma progression using optical coherence tomography (OCT) images, in the absence of a reference standard. Retrospective cohort study. Glaucomatous and healthy eyes with ≥5 reliable peripapillary OCT (Spectralis, Heidelberg Engineering) circle scans were included. A weakly supervised time-series learning model, called Noise Positive-Unlabeled (Noise-PU) DL was developed to classify whether sequences of OCT B-scans showed glaucoma progression. The model used two learning schemes, one to identify age-related changes by differentiating test sequences from glaucoma vs. healthy eyes, and the other to identify test-retest variability based on scrambled OCTs of glaucoma eyes. Both models' bases were convolutional neural networks (CNN) and long short-term memory (LSTM) networks which were combined to form a CNN-LSTM model. Model features were combined and jointly trained to identify glaucoma progression, accounting for age-related loss. The DL model's outcomes were compared with ordinary least squares (OLS) regression of retinal nerve fiber layer (RNFL) thickness over time, matched for specificity. The hit ratio was used as a proxy for sensitivity. 8,785 follow-up sequences of 5 consecutive OCT tests from 3253 eyes (1859 subjects) were included in the study. Mean follow-up time was 3.5±1.6 years. In the test sample, the hit ratios of the DL and OLS methods were 0.498 (95%CI:0.470-0.526) and 0.284 (95%CI:0.258-0.309) respectively (P<0.001) when the specificities were equalized to 95%. A DL model was able to identify longitudinal glaucomatous structural changes in OCT B-scans using a surrogate reference standard for progression.

Assessments of polymerization shrinkage by optical coherence tomography-based digital image correlation analysis—Part I: Parameter identification

ObjectiveTo investigate the feasibility of optical coherence tomography (OCT)-based digital image correlation (DIC) analysis and to identify the experimental parameters for measurements of polymerization shrinkage. MethodsClass I cavities were prepared on bovine incisors and filled with Filtek Z350XT Flowable (Z350F). One OCT image of the polymerized restoration was processed to generate virtually displaced images. In addition, the tooth specimen was physically moved under OCT scanning. A DIC software analyzed these virtual and physical transformation sets and assessed the effects of subset sizes on accuracy. The refractive index of unpolymerized and polymerized Z350F was measured via OCT images. Finally, different particles (70–80 µm glass beads, 150–212 µm glass beads, and 75–150 µm zirconia powder) were added to Z350F to inspect the analyzing quality. ResultsThe analyses revealed a high correlation (>99.99%) for virtual movements within 131 pixels (639 µm) and low errors (<5.21%) within a 10-µm physical movement. A subset size of 51 × 51 pixels demonstrated the convergence of correlation coefficients and calculation time. The refractive index of Z350F did not change significantly after polymerization. Adding glass beads or zirconia particles caused light reflection or shielding in OCT images, whereas blank Z350F produced the best DIC analysis results. SignificanceThe OCT-based DIC analysis with the experimental conditions is feasible in measuring polymerization shrinkage of RBC restorations. The subset size in the DIC analysis should be identified to optimize the analysis conditions and results. Uses of hyper- or hypo-reflective particles is not recommended in this method.

COMBINED CENTRAL RETINAL VASCULAR OCCLUSION AS THE PRESENTING FEATURE IN β-THALASSEMIA WITH IRON DEFICIENCY ANEMIA.

To report a case of β-thalassemia trait with iron deficiency anemia presenting as a combined central retinal vein and artery occlusion. Case report. A 22-year-old woman presented with sudden-onset blurry vision in the left eye of 3-day duration. Best-corrected visual acuity was 20/20 and 20/1000 in right and left eyes, respectively. Fundus examination of the left eye revealed optic disk edema, macular whitening with a cherry-red spot, markedly dilated and tortuous retinal veins, and hemorrhages both around the disk and extending into the macula and the periphery. Fundus fluorescein angiography showed delayed filling of retinal vasculature, dilated and tortuous retinal veins, and blocked fluorescence around and beyond the optic disk. Optical coherence tomography scan at presentation showed hyperreflective inner retinal layers with neurosensory detachment. Optical coherence tomography angiography showed that the vessel densities of superficial and deep capillary plexus were remarkably reduced. A diagnosis of β-thalassemia trait combined with iron deficiency anemia was made after hematologic workup. The patient was treated with a course of oral iron supplements, vasodilator (compound Xueshuantong), inhalation of a mixture of 5% carbon dioxide and 95% oxygen, and a nutritional agent (compound anisoine). Six months later, her visual acuity improved to 20/60 in the left eye with complete resolution of all clinical signs. Combined central retinal vein and artery occlusion is a rare emergency leading to acute vision loss and can manifest in patients with β-thalassemia trait with iron deficiency anemia. Prompt diagnosis and early management is important to treat underlying systemic disorders and to prevent occurrence of a similar episode in fellow eye.

Risk factors for diabetic retinopathy, diabetic macular edema, and sight-threatening diabetic retinopathy

OBJECTIVETo identify the risk factors for the development of diabetic retinopathy (DR), diabetic macular edema (DME), and sight threatening DR (STDR) based on a city-wide diabetes screening program. RESEARCH DESIGN AND METHODSDiabetic patients were prospectively recruited between June 2016 and December 2022. All patients underwent dilated fundus photography centered on the disc and macula or macula spectral domain optical coherence tomography (SD-OCT) scan. Complete medical history was documented.Systematic examination, blood analysis, and urinalysis were performed. Multivariate logistic regression analysis adjusting for age and sex was conducted. RESULTSOut of 7,274 diabetic patients, 6,840 had gradable images, among which 3,054 (42.0%) were graded as DR, 1153 (15.9%) as DME, and 1,500 (20.6%) as STDR. The factors associated with DR, DME, and STDR included younger age (odds ratio [OR]: 0.96, 0.97, and 0.96 respectively), lower BMI (OR: 0.97, 0.95, and 0.95 respectively), longer duration of diabetes (OR: 1.07, 1.03, and 1.05 respectively) and positive of urinary albumin (OR: 2.22, 2.56, and 2.88 respectively). Other associated factors included elevated blood urea nitrogen (OR: 1.22, 1.28, and 1.27 respectively), higher LDL-cholesterol, lower blood haemoglobin (OR: 0.98, 0.98, and 0.98), insulin intake, presence of diabetic foot pathologies and diabetic peripheral neuropathy. We also identified novel risk factors, including high serum potassium (OR: 1.37, 1.46, and 1.55 respectively), high serum sodium (OR: 1.02, 1.02, and 1.04 respectively). Better family income was a protective factor for DR, DME, and STDR. Alcohol consumption once a week was also identified as a protective factor for DR. CONCLUSIONSThis study revealed high serum sodium, high serum potassium, low blood haemoglobin, and the level of family income as novel associated factors for DR, which can help with DR monitoring and management.

Biological and Methodological Variability in Retinal Nerve Fiber Layer OCT: The Framingham Heart Study

Biological and Methodological Variability in Retinal Nerve Fiber Layer OCT: The Framingham Heart Study

Spiral scanning improves subject fixation in widefield retinal imaging.

Point scanning retinal imaging modalities, including confocal scanning light ophthalmoscopy (cSLO) and optical coherence tomography, suffer from fixational motion artifacts. Fixation targets, though effective at reducing eye motion, are infeasible in some applications (e.g., handheld devices) due to their bulk and complexity. Here, we report on a cSLO device that scans the retina in a spiral pattern under pseudo-visible illumination, thus collecting image data while simultaneously projecting, into the subject's vision, the image of a bullseye, which acts as a virtual fixation target. An imaging study of 14 young adult volunteers was conducted to compare the fixational performance of this technique to that of raster scanning, with and without a discrete inline fixation target. Image registration was used to quantify subject eye motion; a strip-wise registration method was used for raster scans, and a novel, to the best of our knowledge, ring-based method was used for spiral scans. Results indicate a statistically significant reduction in eye motion by the use of spiral scanning as compared to raster scanning without a fixation target.

Microscope-integrated optical coherence tomography for in vivo human brain tumor detection with artificial intelligence.

It has been shown that optical coherence tomography (OCT) can identify brain tumor tissue and potentially be used for intraoperative margin diagnostics. However, there is limited evidence on its use in human in vivo settings, particularly in terms of its applicability and accuracy of residual brain tumor detection (RTD). For this reason, a microscope-integrated OCT system was examined to determine in vivo feasibility of RTD after resection with automated scan analysis. Healthy and diseased brain was 3D scanned at the resection edge in 18 brain tumor patients and investigated for its informative value in regard to intraoperative tissue classification. Biopsies were taken at these locations and labeled by a neuropathologist for further analysis as ground truth. Optical OCT properties were obtained, compared, and used for separation with machine learning. In addition, two artificial intelligence-assisted methods were utilized for scan classification, and all approaches were examined for RTD accuracy and compared to standard techniques. In vivo OCT tissue scanning was feasible and easily integrable into the surgical workflow. Measured backscattered light signal intensity, signal attenuation, and signal homogeneity were significantly distinctive in the comparison of scanned white matter to increasing levels of scanned tumor infiltration (p < 0.001) and achieved high values of accuracy (85%) for the detection of diseased brain in the tumor margin with support vector machine separation. A neuronal network approach achieved 82% accuracy and an autoencoder approach 85% accuracy in the detection of diseased brain in the tumor margin. Differentiating cortical gray matter from tumor tissue was not technically feasible in vivo. In vivo OCT scanning of the human brain has been shown to contain significant value for intraoperative RTD, supporting what has previously been discussed for ex vivo OCT brain tumor scanning, with the perspective of complementing current intraoperative methods for this purpose, especially when deciding to withdraw from further resection toward the end of the surgery.

Foveal thickness and vascular variables in adolescents born moderate-to-late preterm.

It is well established that children born very preterm are at increased risk for ocular abnormalities including altered foveal morphology. However, little is known about how children born moderate-to-late preterm (MLP), gestational age 32 + 0-36 + 6 weeks, are affected later in life. This study investigates foveal avascular zone (FAZ) area, vascular density (VD), central foveal thickness (CFT) and ganglion cell layer thickness (GCL++) of adolescents born MLP without history of retinopathy of prematurity and compare the results with full-term controls. In a prospective population-based cohort study, 50 adolescents (26 girls; mean age 16.5 years) born MLP were examined with optical coherence tomography (OCT) and OCT angiography (OCT-A). FAZ and VD were obtained from OCT-A scans and adjusted for ocular magnification. CFT and GCL++ were obtained from the OCT scans. The results from the MLP individuals were compared with the results from 49 healthy full-term controls (29 girls; mean age 16.7 years). The results showed statistically significant differences in FAZ area (0.22 vs 0.28 mm2; p = 0.0032) and CFT (198.1 vs 187.1 μm; p = 0.0010) between the MLP group and controls. Strong correlations between FAZ area and CFT (r = -0.773, p < 0.0001) and GCL++ (r = -0.924, p < 0.0001) were found in the MLP group. There were no differences in VD. Our results show that adolescents born MLP have a smaller FAZ area and an increased CFT compared with full-term controls. These results indicate that adolescents born MLP have similar parafoveal changes as children born extreme or very preterm.

Central retinal artery occlusion after intravitreal brolucizumab injection for treatment-naïve neovascular age-related macular degeneration; a case report

BackgroundTo report a case of central retinal artery occlusion (CRAO) after intravitreal injection of brolucizumab for a treatment-naïve neovascular age-related macular degeneration (nAMD) patient without comorbid cardiovascular disease history.Case presentationA 79-year-old Asian male without a cardiovascular disease history such as diabetes or hypertension underwent three times of monthly consecutive intravitreal brolucizumab injections for treatment of progressed nAMD in his left eye. Two days after the third injection, the patient presented with acute painless visual loss. Typical retinal whitening with a cherry red spot was observed on the fundus photograph, and retinal swelling with hyper-reflectivity was also identified on the optical coherence tomography (OCT) scan. On the fundus fluorescein angiography, arm-to-retina time and arteriovenous transit time were remarkedly delayed, but clinical findings suggesting an intraocular inflammation (IOI) were not observed. Therefore, CRAO was diagnosed, and anterior chamber paracentesis was administrated immediately. However, there had been no improvement in visual acuity during the follow-up period of three months, despite prolonged oral steroid and anti-platelet agent medication.ConclusionsIn rare cases, patients without cardiovascular comorbidities can develop CRAO after intravitreal brolucizumab injection without gross evidence of IOI. Therefore, CRAO should always be in consideration and careful observation is required after intravitreal brolucizumab injection for nAMD patients with old age, even if the patient does not have any other cardiovascular disease history.

Effect of isoflurane anaesthetic time on ocular a-scan ultrasonography measures and their relationship to age and OCT measures in the Guinea pig

A-scan ultrasonography enables precise measurement of internal ocular structures. Historically, its use has underpinned fundamental studies of eye development and aberrant eye growth in animal models of myopia; however, the procedure typically requires anaesthesia. Since anaesthesia affects intra-ocular pressure (IOP), we investigated changes in internal ocular structures with isoflurane exposure and compared measurements with those taken in awake animals using optical coherence tomography (OCT). Continuous A-scan ultrasonography was undertaken in tri-coloured guinea pigs aged 21 (n = 5), 90 (n = 5) or 160 (n = 5) days while anaesthetised (up to 36 min) with isoflurane (5% in 1.5L/min O2). Peaks were selected from ultrasound traces corresponding to the boundaries of the cornea, crystalline lens, retina, choroid and sclera. OCT scans (Zeiss Cirrus Photo 800) of the posterior eye layers were taken in 28-day-old animals (n = 19) and compared with ultrasound traces, with choroid and scleral thickness adjusted for the duration of anaesthesia based on the changes modelled in 21-day-old animals. Ultrasound traces recorded sequentially in left and right eyes in 14-day-old animals (n = 30) were compared, with each adjusted for anaesthesia duration. The thickness of the cornea was measured in enucleated eyes (n = 5) using OCT following the application of ultrasound gel (up to 20 min). Retinal thickness was the only ultrasound internal measure unaffected by anaesthesia. All other internal distances rapidly changed and were well fitted by exponential functions (either rise-to-max or decay). After 10 and 20 min of anaesthesia, the thickness of the cornea, crystalline lens and sclera increased by 17.1% and 23.3%, 0.4% and 0.6%, and 5.2% and 6.5% respectively, whilst the anterior chamber, vitreous chamber and choroid decreased by 4.4% and 6.1%, 0.7% and 1.1%, and 10.7% and 11.8% respectively. In enucleated eyes, prolonged contact of the cornea with ultrasound gel resulted in an increase in thickness of 9.3% after 10 min, accounting for approximately half of the expansion observed in live animals. At the back of the eye, ultrasound measurements of the thickness of the retina, choroid and sclera were highly correlated with those from posterior segment OCT images (R2 = 0.92, p = 1.2 × 10−13, R2 = 0.55, p = 4.0 × 10−4, R2 = 0.72, p = 5.0 × 10−6 respectively). Furthermore, ultrasound measures for all ocular components were highly correlated in left and right eyes measured sequentially, when each was adjusted for anaesthetic depth. This study shows that the depth of ocular components can change dramatically with anaesthesia. Researchers should therefore be wary of these concomitant effects and should employ adjustments to better render ‘true’ values.

Longitudinal change of retinal layer thickness in cognitively normal elderly subjects: population-based cohort study

Purpose: To identify longitudinal retinal layer thickness changes in normal eyes of cognitively healthy older participants. Methods: Post-hoc analysis was performed on 57 cognitively healthy older participants from the population-based KLoSHA and KLOSCAD cohort studies who underwent baseline and final optical coherence tomography (OCT) scans. The peripapillary retinal nerve fiber layer, subfoveal choroid, and average retinal layer thickness at four quadrant (nasal, temporal, superior, and inferior) points 1 mm, 2 mm, and 3 mm from the center of the fovea were measured. Results: Among the analyzed retinal layers, both the ganglion cell-inner plexiform layer (GCIPL) and the outer nuclear layer (ONL) at all 1, 2, and 3 mm points showed a statistically significant decrease in thickness at the final visit compared to baseline. The annual decrease rates were -1.2 μm/year at 1 mm (total -6.6%), -1.3 μm/year at 2 mm (total -8.4%), -1.1 μm/year at 3 mm (total -9.7%) for GCIPL; -0.6 μm/year at 1 mm (total -4.2%), -0.5 μm/year at 2 mm (total -3.9%), and -0.4 μm/year at 3 mm (total -4.1%) for ONL. Conclusions: Age plays a significant role in the reduction of GCIPL and ONL thicknesses in cognitively healthy elderly individuals.

Visual disturbances in a 12-year-old male patient with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes syndrome

Abstract: Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare condition. Here, we present a case of a male patient with a very unique combination of symptoms that started at the age of 12. Transient symptoms manifested after 4 days of high fever and included lethargy, a loss of appetite, and an inability to recognize faces. After that, the patient was symptom-free for 4 years before he was hospitalized again with a working diagnosis of acute disseminated encephalomyelitis. The ophthalmic symptoms at this stage were photophobia and discrete horizontal nystagmus. One year later, the patient had another seizure and during hospitalization, predominantly displayed cerebral symptoms such as dystaxia, dysmetria, generalized muscle hypotrophy, and absent myotonic reflexes. Like before, an ophthalmic examination demonstrated a best-corrected visual acuity of 1.0 and a normal anterior segment. A fundus examination revealed a slightly rarefied retina, along with areas of perifoveal and parapapillary atrophy, in addition to increased vascular tortuosity. Optical coherence tomography scans of the macula and the optic disc depicted a mild thinning of the retinal layers. Visual field testing showed an isopter contraction with a predominant loss of the temporal visual field in both eyes. A genetic serum analysis was positive for mitochondrial mutation m.3243A&gt;G, and a diagnosis of MELAS was confirmed. The treatment included anticonvulsive drugs and dietary precautions. Patients with MELAS syndrome can manifest a wide range of visual disturbances, meaning that a detailed ophthalmic examination is required.

Subretinal transient hyporeflectivity in neovascular age-related macular degeneration and its response to a loading phase of aflibercept: PRECISE report 4.

To describe the prevalence of subretinal transient hyporeflectivity (STHR) in exudative neovascular age-related macular degeneration (nAMD) and its response to a loading phase of aflibercept. Optical coherence tomography (OCT) scans of treatment-naïve nAMD patients captured at baseline and after a loading phase of aflibercept were graded for presence of STHR, defined as a small, well-defined, round, subretinal, hyporeflective area, delimited between the ellipsoid zone (EZ) and the retinal pigmented epithelium/Bruch membrane complex. OCT parameters recorded were macular neovascularisation (MNV) subtypes, location of retinal fluids (subretinal fluid, SRF and intraretinal fluid, IRF), central retinal and choroidal thickness. Response was defined as absence of IRF and SRF. Factors associated with completely resolved STHR versus persistent STHR post-loading phase were compared. 2039 eyes of 1901 patients were analysed. STHR was observed in 79 eyes of 78 patients, with an estimated prevalence of 3.87% (95% CI 3.08-4.81%). STHR were seen in 44 type 1 MNV (56%), 27 with type 2 (34%), and 8 with type 3 (10%). At baseline, a total of 303 STHR were present, ranging between 1-22 per eye. The total number of STHR reduced significantly after the loading phase to 173 (p = 0.002). Complete disappearance of STHR was seen in 44 eyes (56%) and persistent STHR in the rest (44%). STHR may represent a marker of low-grade exudation in nAMD eyes with good response to a loading phase of aflibercept. However, its potential role as an independent nAMD activity biomarker is limited as most resolve after the loading phase.

The role of ultra-widefield imaging with navigated central and peripheral cross-sectional and three-dimensional swept source optical coherence tomography in ophthalmology: Clinical applications

Abstract: PURPOSE: To assess central and peripheral retinal and choroidal diseases using ultra-widefield (UWF) fundus imaging in combination with navigated central and peripheral cross-sectional and three-dimensional (3D) swept source optical coherence tomography (SS-OCT) scans. METHODS: Retrospective study involving 332 consecutive patients, with a nearly equal distribution of males and females. The mean age of patients was 52 years (range 18–92 years). Average refractive error was −3.80 D (range +7.75 to −20.75 D). RESULTS: The observations in this study demonstrate the efficacy of peripheral navigated SS-OCT in assessing various ocular conditions. The technology provides high-quality images of the peripheral vitreous, vitreoretinal interface, retina, and choroid, enabling visualization of vitreous floaters and opacities, retinal holes and tears, pigmented lesions, and peripheral retinal degenerations. 3D OCT scans enhance the visualization of these abnormalities and improve diagnostic and therapeutic decisions. CONCLUSION: Navigated central and peripheral cross-sectional and 3D SS-OCT scans offer significant complementary benefits in the assessment and management of retinal diseases. Their addition to UWF imaging provides a comprehensive view of central and peripheral ocular structures, aiding in early detection, precise anatomical measurements, and objective monitoring of disease progression. In addition, this technology serves as a valuable tool for patient education, a teaching tool for trainees, and documentation for medico-legal purposes.

Multimodal in-vivo maps as a tool to characterize retinal structural biomarkers for progression in adult-onset Stargardt disease

PurposeTo characterize retinal structural biomarkers for progression in adult-onset Stargardt disease from multimodal retinal imaging in-vivo maps.MethodsSeven adult patients (29–69 years; 3 males) with genetically-confirmed and clinically diagnosed adult-onset Stargardt disease and age-matched healthy controls were imaged with confocal and non-confocal Adaptive Optics Scanning Light Ophthalmoscopy (AOSLO), optical coherence tomography (OCT), fundus infrared (FIR), short wavelength-autofluorescence (FAF) and color fundus photography (CFP). Images from each modality were scaled for differences in lateral magnification before montages of AOSLO images were aligned with en-face FIR, FAF and OCT scans to explore changes in retinal structure across imaging modalities. Photoreceptors, retinal pigment epithelium (RPE) cells, flecks, and other retinal alterations in macular regions were identified, delineated, and correlated across imaging modalities. Retinal layer-thicknesses were extracted from segmented OCT images in areas of normal appearance on clinical imaging and intact outer retinal structure on OCT. Eccentricity dependency in cell density was compared with retinal thickness and outer retinal layer thickness, evaluated across patients, and compared with data from healthy controls.ResultsIn patients with Stargardt disease, alterations in retinal structure were visible in different image modalities depending on layer location and structural properties. The patients had highly variable foveal structure, associated with equally variable visual acuity (-0.02 to 0.98 logMAR). Cone and rod photoreceptors, as well as RPE-like structures in some areas, could be quantified on non-confocal split-detection AOSLO images. RPE cells were also visible on dark field AOSLO images close to the foveal center. Hypo-reflective gaps of non-waveguiding cones (dark cones) were seen on confocal AOSLO in regions with clinically normal CFP, FIR, FAF and OCT appearance and an intact cone inner segment mosaic in three patients.ConclusionDark cones were identified as a possible first sign of retinal disease progression in adult-onset Stargardt disease as these are observed in retinal locations with otherwise normal appearance and outer retinal thickness. This corroborates a previous report where dark cones were proposed as a first sign of progression in childhood-onset Stargardt disease. This also supports the hypothesis that, in Stargardt disease, photoreceptor degeneration occurs before RPE cell death.