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1.
Retina ; 44(7): 1115-1123, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38478760

ABSTRACT

PURPOSE: To investigate the correlation between diabetic retinopathy (DR) severity and microscopic retinal and vascular alterations using adaptive optics imaging. METHODS: In this single-center, prospective cohort study, adult participants with healthy eyes or DR underwent adaptive optics imaging. Participants were classified into control/mild nonproliferative DR, moderate/severe nonproliferative DR, and proliferative DR. Adaptive optics imaging using the RTX1 camera was obtained from 48 participants (87 eyes) for photoreceptor data and from 36 participants (62 eyes) for vascular data. RESULTS: Photoreceptor parameters significantly differed between DR groups at 2° and 4° of retinal eccentricity. Wall-to-lumen ratio varied significantly at 2° eccentricity, while other vascular parameters remained nonsignificant. Cone density and dispersion were the strongest predictors for DR severity ( P < 0.001) in multivariable generalized estimating equation modeling, while other vascular parameters remained nonsignificant between DR severity groups. All photoreceptor parameters showed significant correlations with visual acuity overall and across most DR severity groups. CONCLUSION: To date, this is one of the largest studies evaluating the use of adaptive optics imaging in DR. Adaptive optics imaging was demonstrated to differentiate between various levels of disease severity in DR. These results support the potential role in diagnostic and therapeutic microstructural evaluation in research and clinical practice.


Subject(s)
Diabetic Retinopathy , Visual Acuity , Humans , Diabetic Retinopathy/diagnosis , Diabetic Retinopathy/physiopathology , Prospective Studies , Male , Female , Middle Aged , Visual Acuity/physiology , Adult , Aged , Retinal Vessels/diagnostic imaging , Retinal Vessels/pathology
2.
Retina ; 44(4): 558-564, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-37948741

ABSTRACT

PURPOSE: Manual extraction of spectral domain optical coherence tomography (SD-OCT) reports is time and resource intensive. This study aimed to develop an optical character recognition (OCR) algorithm for automated data extraction from Cirrus SD-OCT macular cube reports. METHODS: SD-OCT monocular macular cube reports (n = 675) were randomly selected from a single-center database of patients from 2020 to 2023. Image processing and bounding box operations were performed, and Tesseract (an OCR library) was used to develop the algorithm, OCTess. The algorithm was validated using a separate test data set. RESULTS: The long short-term memory deep learning version of Tesseract achieved the best performance. After reverifying all discrepancies between human and algorithmic data extractions, OCTess achieved accuracies of 100.00% and 99.98% in the training (n = 125) and testing (n = 550) datasets, while the human error rate was 1.11% (98.89% accuracy) and 0.49% (99.51% accuracy) in each, respectively. OCTess extracted data in 3.1 seconds, compared with 94.3 seconds per report for human evaluators. CONCLUSION: We developed an OCR and machine learning algorithm that extracted SD-OCT data with near-perfect accuracy, outperforming humans in both accuracy and efficiency. This algorithm can be used for efficient construction of large-scale SD-OCT data sets for researchers and clinicians.


Subject(s)
Algorithms , Tomography, Optical Coherence , Humans , Tomography, Optical Coherence/methods , Machine Learning
4.
Retina ; 43(5): 775-783, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36729013

ABSTRACT

PURPOSE: To compare foveal avascular zone (FAZ) geometric indices using optical coherence tomography angiography (OCTA) in pneumatic retinopexy (PnR) versus pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD). FAZ morphology was assessed as a possible imaging feature of retinal displacement. METHODS: This ALIGN post hoc analysis included primary fovea-off RRDs that underwent successful PnR or PPV, and performed OCTA, and fundus autofluorescence at (FAF) 3 months postoperatively at St. Michael's Hospital, Toronto, Canada. FAZ area (mm 2 ), axial ratio, circularity, and roundness were measured, and FAF images were assessed for retinal displacement. RESULTS: Seventy-two patients were included, 78% (56/72) were male mean age was 60 ± 9 years, and 60% (43/72) were phakic. Sixty-five percent (47/72) and 35% (25/72) underwent PnR and PPV, respectively. The mean baseline logarithm of the minimum angle of resolution visual acuity was 1.49 ± 0.76. FAZ circularity was lower after PPV (0.629 ± 0.120) versus PnR (0.703 ± 0.122); P = 0.016. Sixty-six patients had gradable FAF images. Retinal displacement was present in 29% (19/66), 84.2% (16/19) of which had displacement in the macula. FAZ circularity was lower in eyes with displacement in the macula (0.613 ± 0.110) versus those without displacement (0.700 ± 0.124); P = 0.015. There was a moderate negative correlation between 12-month aniseikonia and FAZ circularity(r = -0.262; P = 0.041). CONCLUSION: FAZ circularity was lower after PPV and in eyes with retinal displacement in the macula. Circularity was negatively correlated with 12-month aniseikonia scores. FAZ circularity may be another imaging feature to consider postoperatively after RRD repair.


Subject(s)
Aniseikonia , Macula Lutea , Retinal Detachment , Humans , Male , Middle Aged , Aged , Female , Retinal Detachment/diagnosis , Retinal Detachment/surgery , Tomography, Optical Coherence/methods , Fluorescein Angiography/methods , Vitrectomy/methods , Retrospective Studies
5.
Ophthalmol Retina ; 7(4): 333-337, 2023 04.
Article in English | MEDLINE | ID: mdl-36441084

ABSTRACT

PURPOSE: To describe the clinical features and visual outcomes of eyes with conjunctival haptic erosion after sutureless intrascleral (SIS) fixated intraocular lens (IOL) placement. DESIGN: Retrospective case series. SUBJECTS: Patients experiencing haptic erosion after SIS fixation between January 1, 2013, and March 1, 2022. METHODS: A multicenter, multisurgeon, retrospective review. MAIN OUTCOME MEASURES: Clinical features, visual outcomes, and treatment options following haptic erosions after SIS fixation. RESULTS: Nineteen eyes with haptic erosion were identified. The mean age at initial SIS fixation was 64 ± 12 years (range, 38-81 years). There were 5 (26%) eyes with a history of conjunctiva involving ocular surgery, including scleral buckle surgery and tube shunt surgery. Trocar-assisted fixation was performed in 15 (79%) eyes, whereas needle fixation was used in 4 (21%) eyes. Eighteen (95%) sets of haptics were flanged with a low temperature cautery. Seventeen (90%) sets of haptics were externalized superiorly and inferiorly, and 2 (10%) sets of haptics were externalized nasally and temporally. Haptics were covered by conjunctiva in 14 (74%) eyes and by scleral flap in 5 (26%) eyes. All patients experienced a single haptic erosion, of which 8 (43%) were located superiorly, 9 (47%) inferiorly, and 2 (10%) temporally. The mean interval between the initial SIS fixation and haptic erosion was 278 ± 437 days. After correction of the erosion, 18 (95%) eyes had a stable IOL at the last follow-up, with no recurrence of haptic erosion. In this series, there were no cases of endophthalmitis. CONCLUSIONS: Haptic erosion is a notable complication after SIS fixated IOL surgery but may be repaired with favorable visual outcomes. Careful evaluation of the conjunctiva should be considered before the surgery. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.


Subject(s)
Lens Implantation, Intraocular , Lenses, Intraocular , Humans , Adult , Middle Aged , Aged , Aged, 80 and over , Retrospective Studies , Haptic Technology , Sclera/surgery
6.
J Cancer Sci Ther ; 5(2): 52-57, 2013.
Article in English | MEDLINE | ID: mdl-23459697

ABSTRACT

Doxorubicin (Dox) is one of the most effective chemotherapeutic agents; however, it causes dose-dependent cardiotoxicity. Evaluation of left ventricular function relies on measurements based on M-mode echocardiography. A new technique based on quantification of myocardial motion and deformation, strain echocardiography, has been showed promising profile for early detection of cardiac dysfunction. Different therapy strategies, such as flavonoid plant extracts and stem cells, have been investigated to improve heart function in toxic cardiomyopathy. This work aimed to assess early cardiac function improvement after treatments with either flavonoid extract from Camellia sinensis or mesenchymal stem cells in Dox cardiotoxicity using strain echocardiography. Twenty Wistar rats were randomly assigned to four groups. They received water (control, Dox, Dox + stem cells) or 100 mg/kg C. sinensis extract (Dox + C. sinensis) via gavage, daily, for four weeks. Animals also received saline (control) or 5 mg/kg doxorubicin (Dox, Dox + C. sinensis, Dox + stem cells) via intraperitoneal injection, weekly, for four weeks. Stem cells were injected (3 × 106 cells) through tail vein prior the beginning of the experiment (Dox + stem cells). Animals were evaluated by hematological, electrocardiography, echocardiography, and histopathological examinations. Dox cardiotoxicity was only diagnosed with strain echocardiography, detecting a decrease in ventricular function. C. sinensis extract did not prevent ventricular dysfunction induced by Dox. However, strain echocardiography examination revealed that Dox cardiotoxicity was significantly suppressed in rats treated with stem cells. In conclusion, strain echocardiography was able to detect precocity signs of heart failure and stem cell therapy showed cardioprotection effect against Dox cardiotoxicity.

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