Correlations between subfoveal choroidal thickness, macular thickness, and visual outcome in neovascular age-related macular degeneration using swept source OCT: insights from intravitreal aflibercept treatment.

BACKGROUND: Age-related macular degeneration (AMD) is a leading cause of visual impairment among individuals aged 50 and above, often resulting in irreversible vision loss (1). Currently, antiangiogenic therapy is the primary treatment approach for neovascular AMD (2). The choroid has gained significant attention in recent years due to its involvement in various ocular pathologies (7). The objective of this study was to evaluate visual acuity and correlate pre-treatment variables, such as foveal thickness and choroidal thickness, with post-treatment outcomes. MATERIALS AND METHODS: This study was designed as a prospective interventional study to investigate the changes in choroidal and macular thickness in patients with neovascular AMD who received intravitreal aflibercept injections. The study utilized medical records and employed Swept Source Optical Coherence Tomography (OCT-SS) for evaluation. The data was collected from patients treated in Presidente Prudente, Brazil, during a three-month load dose period. RESULTS: The best-corrected mean visual acuity significantly improved from 1.0 logarithm of the minimum resolution angle (logMAR) units to 0.55 logMAR after treatment with aflibercept (p < 0.001). Patients undergoing treatment exhibited a significant decrease in average macular thickness from 323 µm to 232 µm (p = 0.001), as well as a reduction in choroidal thickness from 206 µm to 172 µm (p = 0.031), while maintaining intraocular pressure within the normal range (p = 0.719) without significant variation. Statistically significant associations were found between the difference in pre- and post-treatment choroidal thickness and the pretreatment values of macular thickness (p = 0.005) and choroidal thickness (p = 0.013). There was also a statistically significant correlation between the difference in pre- and post-treatment macular thickness and the pretreatment macular thickness value (p < 0.001). CONCLUSION: In this study, aflibercept exhibited remarkable effectiveness in reducing macular and choroidal thickness, as evaluated using OCT-SS, and significantly improved visual acuity in patients with neovascular AMD. The assessment of both choroidal and macular changes, as well as their correlations, can provide valuable insights for clinicians, enabling them to make well-informed therapeutic decisions and effectively monitor treatment outcomes. Notably, this study contributes to the existing body of literature as the first to establish a correlation between pretreatment foveal thickness, variation in choroidal thickness, and post-treatment choroidal thickness.

Agreement between Two Swept-source Optical Coherence Tomography: Optic Nerve Head, Retinal Nerve Fiber Layer and Ganglion Cell Layers in Healthy Eyes.

Aim and background: Precision of optical coherence tomography (OCT) measurements of the optic nerve head (ONH), retinal nerve fiber layer (RNFL), and macular ganglion cell layer (GCL) is essential for the diagnosis and monitoring of glaucoma. The purpose of this research was to evaluate the repeatability and reproducibility of retinal and ONH parameters measured with two identical swept-source optical coherence devices. Methods: A cross-sectional study was conducted. A total of 30 eyes of 15 healthy subjects were included. Two technicians performed four OCT-wide protocol scans in the same visit using two identical Triton swept-source OCT (DRI-OCT) instruments. The interdevice and interobserver reproducibility and the repeatability of both instruments for all ONH, RNFL, and macular GCL parameters were evaluated by the intraclass correlation coefficient (ICC). Additionally, Bland-Altman test analysis was used for repeatability and reproducibility measurements. Results: Intraclass correlation coefficient (ICCs) of the ONH, RNFL, and GCL measurements were excellent for repeatability and interdevice reproducibility (>0.9). Interobserver reproducibility was good for all parameters except for RNFL clock hour 11 (ICC = 0.72). The variability of the average RNFL was from -4.103 to 4.97 µm, with a mean percentage of the difference (PD) of 0.37 ± 2.03%. Among GCL parameters, the greatest variability was found in the inferior sector (PD = -0.88 ± 5.39%, limits of agreement (LoA) = -8.345-7.078 µm). Conclusion: Using two identical swept-source OCT instruments for the evaluation of the structural parameters of the ONH, RNFL, and macular GCL showed high repeatability and reproducibility. This allows the clinician to make a therapeutic decision based on OCT findings coupled with the clinical evaluation of the patient. When evaluating RNFL clock hours measurements, interobserver reproducibility might decrease. Clinical significance: The understanding of measurement variability while using different devices and the impact of the observer capturing the images, is clinically relevant. How to cite this article: Prada AM, Tello A, Rangel CM, et al. Agreement between Two Swept-source Optical Coherence Tomography: Optic Nerve Head, Retinal Nerve Fiber Layer and Ganglion Cell Layers in Healthy Eyes. J Curr Glaucoma Pract 2023;17(2):85-90.

Ocular biometry in dense cataracts: Comparison of partial-coherence interferometry, swept-source optical coherence tomography and immersion ultrasound.

PURPOSE: To assess the axial length (AL) measurement failure rate using partial-coherence interferometry (PCI) and swept-source optical coherence tomography (SS-OCT) in dense cataracts. As a secondary outcome, the SS-OCT biometry was compared to immersion ultrasound. METHODS: This is a prospective cross-sectional and comparative study. Seventy eyes from 70 patients with dense cataracts were enrolled in this study. Dense cataract was defined according to the Lens Opacities Classification System III (LOCS III) scores equal to or more than NO4, NC4, C4, and P3. The failure rate of AL measurement was evaluated using PCI and SS-OCT. Anterior chamber depth (ACD), lens thickness (LT), and AL measurements obtained by SS-OCT were compared with IUS. RESULTS: AL measurement failure rate with PCI was 68.57% and 21.43% with SS-OCT (P = 0.007). AL measurement was achieved in 69.23% of NO4, 66.6% of P3, and 15.3% of mixed cataracts using PCI, while SS-OCT was achieved in 100% of NO4, NO5, P3, and P5 and 76.9% of mixed cataracts. Cortical cataracts alone did not influence AL measurement. Biometric data of ACD, LT, and AL were statistically different comparing US and SS-OCT with a good correlation of AL. CONCLUSION: SS-OCT significantly improves the rate of successful AL measurements when compared to PCI in dense cataracts. The LOCS III clinical cut-off for the use of SS-OCT ocular biometry may well be up to P4 and NO5.

Elucidation of the role of the lamina cribrosa in glaucoma using optical coherence tomography.

Glaucoma is a chronic and progressive optic neuropathy characterized by the death of retinal ganglion cells and corresponding visual field loss. Despite the growing number of studies on the subject, the pathogenesis of the disease remains unclear. Notwithstanding, several studies have shown that the lamina cribrosa (LC) is considered an anatomic site of glaucomatous optic nerve injury, thus having a key role in the pathophysiology of glaucoma development and progression. Different morphological alterations of the LC have been described in vivo in glaucomatous eyes after the evolution of optical coherence tomography (OCT) devices. The most relevant findings were the reduction of laminar thickness, the presence of localized defects, and the posterior LC displacement. These new laminar parameters documented through OCT are not only promising as possible additional tools for glaucoma diagnosis and monitoring, but also as predictors of disease progression. In spite of the advance of technology, however, proper evaluation of the LC is not yet viable in all eyes. We describe OCT-identified LC changes related to the development and progression of glaucoma and provide future directions based on a critical data analysis, focusing on its clinical relevance and applicability.

Agreement between the Swept-Source Optical Coherence Tomography and the Image-Guided System for Biometry Assessment in Cataract Surgery.

PURPOSE: To assess the agreement on biometric data obtained using the Verion image-guided surgery system and the swept-source-OCT biometer IOL Master 700. MATERIALS AND METHODS: All patients underwent biometry using the SS-OCT and the Image-Guide System. The comparison between instruments was assessed using the Intraclass correlation coefficient (ICC). Level of Agreement (LoA) employing the Bland-Altman analysis. RESULTS: The image-based system produced significantly higher keratometry values, evidencing a low LoA between the SS-OCT and the image-based system, ranging from -1.30 D to 0.65 D (1.95 D), -1.04 D to 0.72 D (1.76 D), and -1.31 D to 0.65 D (1.96 D), respectively. The LoA for the Cylinder ranged from -0.46 D to 0.74 D (1.2 D) and from 0.82 to 0.94 mm for WTW. CONCLUSIONS: In our study, the SS-OCT biometer and the Image-based System evidenced statistically significant differences in measuring the main biometric parameters except for the WTW.

Surgical technique: Autologous scleral flap for optic disk pit maculopathy.

PURPOSE: To present a clinical case and surgical technique for management of optic disk pit (ODP) maculopathy. METHODS: Surgical technique video of lens sparring pars plana vitrectomy, autologous scleral flap insertion and gas tamponade. RESULTS: After 1 year follow-up visual acuity was restored to 20/25, retinal serous detachment and schisis were resolved and the autologous scleral flap remained in the (ODP). CONCLUSION: In this case, treatment with pars plana vitrectomy autologous scleral flap insertion and gas tamponade for optic pit maculopathy provided satisfactory anatomical and functional results.

Correlation between cognitive impairment and retinal neural loss assessed by swept-source optical coherence tomography in patients with mild cognitive impairment.

INTRODUCTION: We compared peripapillary retinal nerve fiber layer and macular thickness measurements in patients with mild cognitive impairment (MCI) and control subjects using swept-source optical coherence tomography (SS-OCT). We also assessed the relationship between SS-OCT measurements and the severity of cognitive impairment. METHODS: Peripapillary retinal nerve fiber layer and macular thickness were measured in 23 patients and 24 control subjects using SS-OCT. Cognitive status was assessed using the Mini-Mental State Examination, the Montreal Cognitive Assessment, and the Pfeffer Questionnaire. RESULTS: Most inner retinal layer thickness parameters were significantly smaller in patients with MCI, especially macular ganglion cell complex thickness measurements. Mini-Mental State Examination and Montreal Cognitive Assessment findings were significantly correlated with most macular thickness parameters. DISCUSSION: The SS-OCT-measured inner retinal layers of patients with MCI displayed thinning, especially in the central macular area. SS-OCT technology can provide useful information on ocular involvement patterns and holds promise as an ocular biomarker in this patient population.

Swept-source OCT in patients with multiple evanescent white dot syndrome.

BACKGROUND: Swept-source optical coherence tomography (SS-OCT) has a higher scanning rate and longer wavelength in comparison with spectral-domain OCT (SD-OCT), allowing an improved imaging of retinal vascular plexuses and choriocapillaris. The present two patients diagnosed with multiple evanescent white dot syndrome (MEWDS) underwent fundus autofluorescence (FAF), en-face SS-OCT, and SS-OCT angiography (OCTA) imaging, and its features were described and correlated. RESULTS: The clinical and imaging findings of both cases were consistent with the diagnosis of MEWDS. Color fundus photograph revealed subtle deep retinal white spots in the posterior pole and around the optic disk. FAF showed several hyperautofluorescent lesions corresponding topographically to the subtle deep retinal white lesions observed on color fundus photographs. Cross-sectional SS-OCT showed disruption of the ellipsoid zone (EZ) within the macular area in all study patients. En-face SS-OCT at the level of the outer retina showed lower reflectivity correspondent to the diffuse attenuation due to the EZ disruption on cross-sectional OCT. SS-OCTA demonstrated flow preservation within the retinal vasculature and choriocapillaris. CONCLUSIONS: SS-OCT imaging allows a better visualization of the choriocapillaris, and its normal appearance in MEWDS may suggest that the outer retina and photoreceptors represent the primary site of inflammation.

Comparison of retina specialist preferences regarding spectral-domain and swept-source optical coherence tomography angiography.

PURPOSE: The aim of this study was to compare physician preferences regarding the commercially available spectral-domain (SD) optical coherence tomography angiography (OCTA) and swept-source (SS) OCTA prototype device. DESIGN: Comparative analysis of diagnostic instruments was performed. PATIENTS AND METHODS: Subjects at the University of Washington Eye Institute and Harborview Medical Center were prospectively recruited and imaged with the Zeiss SD OCTA (HD-5000, Angioplex) and Zeiss SS OCTA (Plex Elite, Everest) devices on the same day. The study included 10 eyes from 10 subjects diagnosed with a retinal/choroidal disease. Deidentified images were compiled into a survey and sent to retina specialists in various countries. The survey presented masked SD and SS images of each eye for each retinal sublayer side by side. Respondents were asked about their image preference and impact on clinical management. A priori and post hoc preferences for SD vs SS were collected. RESULTS: Fifty-four retina specialists responded to the survey. Median years in practice was 3.00 (interquartile range [IQR] 1.50-17.00). At baseline, 23 (48%) physicians owned an OCTA machine. The majority of physician responses showed a preference for the SS over SD OCTA, independent of the retinal pathology shown (n=454 overall responses, 74%). Nevertheless, the majority indicated that both SD and SS would be equally valuable in informing clinical decisions (n=374 overall responses, 61%). CONCLUSION: These findings indicate that the majority of retina specialists surveyed prefer SS over SD OCTA based on image quality, regardless of the retinal pathology shown. Regarding the clinical utility of each modality, the majority of physicians perceive SD and SS as equally effective.