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Directional reflectivity of the ellipsoid zone in dry age-related macular degeneration

- Griffin, Shane, Jia, Yali, Johnson, Alicia, Antony, Bhavna, McDonald, H. Richard, Johnson, Robert, Lujan, Brandon

  • Authors: Griffin, Shane , Jia, Yali , Johnson, Alicia , Antony, Bhavna , McDonald, H. Richard , Johnson, Robert , Lujan, Brandon
  • Date: 2021
  • Type: Text , Journal article
  • Relation: Ophthalmic surgery, lasers & imaging retinq Vol. 52, no. 3 (2021), p. 145-152
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  • Description: BACKGROUND AND OBJECTIVE: Ellipsoid zone (EZ) reflectivity on optical coherence tomography (OCT) is affected by the orientation of the scanning beam. The authors sought to determine how directional reflectivity changes in dry age-related macular degeneration (AMD). PATIENTS AND METHODS: Retrospective image analysis included 17 control and 20 dry AMD subjects. Directional OCT (D-OCT) was performed using multiple displaced pupil entrance positions. EZ pixel values and apparent incidence angles were measured. RESULTS: EZ reflectivity decreased in off-axis scans in controls ( P < .001), AMD areas between drusen ( P < .001), and AMD areas overlying drusen ( P < .001). The magnitude of decrement in EZ reflectivity was significantly higher when incidence angles exceeded 10° in controls than in AMD areas between drusen ( P = .024). CONCLUSION: EZ reflectivity in dry AMD may vary by incident angle of light less than in controls, possibly indicating alteration of photoreceptor orientation or integrity. [ Ophthalmic Surg Lasers Imaging Retina. 2021 52:145–152.]

The henle fiber layer in albinism: Comparison to normal and relationship to outer nuclear layer thickness and foveal cone density

- Lee, Daniel, Woertz, Erica, Visotcky, Alexis, Wilk, Melissa, Heitkotter, Heather, Linderman, Rachel, Tarima, Sergey, Summers, C. Gail, Brooks, Brian, Brilliant, Murray, Antony, Bhavna, Lujan, Brandon, Carroll, Joseph

  • Authors: Lee, Daniel , Woertz, Erica , Visotcky, Alexis , Wilk, Melissa , Heitkotter, Heather , Linderman, Rachel , Tarima, Sergey , Summers, C. Gail , Brooks, Brian , Brilliant, Murray , Antony, Bhavna , Lujan, Brandon , Carroll, Joseph
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Investigative Ophthalmology & visual science Vol. 59, no. 13 (2018), p. 5336-5348
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  • Description: Directional optical coherence tomography (D-OCT) allows the visualization of the Henle fiber layer (HFL) in vivo. Here, we used D-OCT to characterize the HFL and outer nuclear layer (ONL) in albinism and examine the relationship between true foveal ONL and peak cone density. Horizontal D-OCT B-scans were acquired, registered, and averaged for 12 subjects with oculocutaneous albinism and 26 control subjects. Averaged images were manually segmented to extract HFL and ONL thickness. Adaptive optics scanning light ophthalmoscopy was used to acquire images of the foveal cone mosaic in 10 subjects with albinism, from which peak cone density was assessed. Across the foveal region, the HFL topography was different between subjects with albinism and normal controls. In particular, foveal HFL thickness was thicker in albinism than in normal controls (P < 0.0001), whereas foveal ONL thickness was thinner in albinism than in normal controls (P < 0.0001). The total HFL and ONL thickness was not significantly different between albinism and controls (P = 0.3169). Foveal ONL thickness was positively correlated with peak cone density in subjects with albinism (r = 0.8061, P = 0.0072). Foveal HFL and ONL topography are significantly altered in albinism relative to normal controls. Our data suggest that increased foveal cone packing drives the formation of Henle fibers, more so than the lateral displacement of inner retinal neurons (which is reduced in albinism). The ability to quantify foveal ONL and HFL may help further stratify grading schemes used to assess foveal hypoplasia.

Retinal optical coherence tomography image enhancement via deep learning

- Halupka, Kerry, Antony, Bhavna, Lee, Matthew, Lucy, Katie, Rai, Ravneet, Ishikawa, Hiroshi, Wollstein, Gadi, Schuman, Joel, Garnavi, Rahil

  • Authors: Halupka, Kerry , Antony, Bhavna , Lee, Matthew , Lucy, Katie , Rai, Ravneet , Ishikawa, Hiroshi , Wollstein, Gadi , Schuman, Joel , Garnavi, Rahil
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Biomedical Optics Express Vol. 9, no. 12 (2018), p. 6205-6221
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  • Description: Optical coherence tomography (OCT) images of the retina are a powerful tool for diagnosing and monitoring eye disease. However, they are plagued by speckle noise, which reduces image quality and reliability of assessment. This paper introduces a novel speckle reduction method inspired by the recent successes of deep learning in medical imaging. We present two versions of the network to reflect the needs and preferences of different end-users. Specifically, we train a convolution neural network to denoise cross-sections from OCT volumes of healthy eyes using either (1) mean-squared error, or (2) a generative adversarial network (GAN) with Wasserstein distance and perceptual similarity. We then interrogate the success of both methods with extensive quantitative and qualitative metrics on cross-sections from both healthy and glaucomatous eyes. The results show that the former approach provides state-of-the-art improvement in quantitative metrics such as PSNR and SSIM, and aids layer segmentation. However, the latter approach, which puts more weight on visual perception, outperformed for qualitative comparisons based on accuracy, clarity, and personal preference. Overall, our results demonstrate the effectiveness and efficiency of a deep learning approach to denoising OCT images, while maintaining subtle details in the images.

Individual differences and transfer of visual anticipation in expert female field hockey goalkeepers

- Morris-Binelli, Khaya, Müller, Sean, Van Rens, Fleur, Harbaugh, Allen, Rosalie, Simon

  • Authors: Morris-Binelli, Khaya , Müller, Sean , Van Rens, Fleur , Harbaugh, Allen , Rosalie, Simon
  • Date: 2022
  • Type: Text , Journal article
  • Relation: Optometry and Vision Science Vol. 99, no. 2 (2022), p. 150-158
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  • Description: SIGNIFICANCE Visual anticipation is vital for performance in several domains such as driving, military, and high-speed interceptive sports, as it enables performers to handle severe time constraints. There has been little investigation into individual differences of anticipation skill transfer within a domain, which can guide training of anticipation to improve performance. PURPOSE The purpose of this study was to investigate individual differences in the transfer of anticipation within a domain, specifically anticipation of the field hockey penalty corner drag-flick across different opponents. METHODS Eight female Australian international and national field hockey goalkeepers participated. Goalkeepers completed female and male opponent penalty corner drag-flick temporal occlusion tests that presented contextual defensive runner positioning relative to the penalty spot, drag-flicker kinematics, and ball flight. RESULTS Drag-flick movement time and ball velocity were significantly different across female and male opponents confirming that a transfer continuum existed. Five goalkeepers could transfer integration of runner contextual and drag-flicker kinematic information to anticipate loose runs above chance from female to male opponent tests. None of the goalkeepers could transfer integration of contextual and kinematic information for the tight runs across female to male opponents. CONCLUSIONS An individual differences approach with truly expert performers provided unique insights into the mechanism of anticipation transfer within a domain. The findings of this study contribute to theoretical and applied knowledge, which can guide the training of anticipation skill to prepare individuals for superior performance. © Lippincott Williams & Wilkins.

Retinal microstructural changes reflecting treatment-associated cognitive dysfunction in patients with lower-grade gliomas

- Nisanova, Arina, Parajuli, Ashutosh, Antony, Bhavna, Aboud, Orwa, Sun, Jinger, Daly, Megan, Fragoso, Ruben, Yiu, Glenn, Liu, Yin

Directional optical coherence tomography imaging of macular pathology

- Lujan, Brandon, Griffin, Shane, Makhijani, Vikram, Antony, Bhavna, Chew, Emily, Roorda, Austin, McDonald, Henry

  • Authors: Lujan, Brandon , Griffin, Shane , Makhijani, Vikram , Antony, Bhavna , Chew, Emily , Roorda, Austin , McDonald, Henry
  • Date: 2024
  • Type: Text , Journal article
  • Relation: Retina Vol. 44, no. 7 (2024), p. 1124-1133
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  • Description: Purpose: To survey the impact of directional reflectivity on structures within optical coherence tomography images in retinal pathology. Methods: Sets of commercial optical coherence tomography images taken from multiple pupil positions were analyzed. These directional optical coherence tomography sets revealed directionally reflective structures within the retina. After ensuring sufficient image quality, resulting hybrid and composite images were characterized by assessing the Henle fiber layer, outer nuclear layer, ellipsoid zone, and interdigitation zone. Additionally, hybrid images were reviewed for novel directionally reflective pathological features. Results: Cross-sectional directional optical coherence tomography image sets were obtained in 75 eyes of 58 patients having a broad range of retinal pathologies. All cases showed improved visualization of the outer nuclear layer/Henle fiber layer interface, and outer nuclear layer thinning was, therefore, more apparent in several cases. The ellipsoid zone and interdigitation zone also demonstrated attenuation where a geometric impact of underlying pathology affected their orientation. Misdirected photoreceptors were also noted as a consistent direction-dependent change in ellipsoid zone reflectivity between regions of normal and absent ellipsoid zone. Conclusion: Directional optical coherence tomography enhances the understanding of retinal anatomy and pathology. This optical contrast yields more accurate identification of retinal structures and possible imaging biomarkers for photoreceptor-related pathology. © 2024 Lippincott Williams and Wilkins. All rights reserved.

Global estimates on the number of people blind or visually impaired by cataract: a meta-analysis from 2000 to 2020

- Pesudovs, Konrad, Lansingh, Van, Kempen, John, Tapply, Ian, Fernandes, Arthur, Cicinelli, Maria, Arrigo, Alexsandro, Leveziel, Nicolas, Resnikoff, Serge, Taylor, Hugh, Sedighi, Tabassom, Flaxman, Seth, Bikbov, Mukkharram, Braithwaite, Tasanee, Bron, Alain, Cheng, Ching-Yu, Del Monte, Monte, Ehrlich, Joshua, Ellwein, Leon, Friedman, David, Furtado, Joao, Gazzard, Gus, George, Ronnie, Hartnett, Mary, Jonas, Jost, Kahloun, Rim, Khairallah, Moncef, Khanna, Rohit, Leasher, Janet, Banik, Biswajit

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