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Cureus Jan 2024Background and objectives Over the years, several treatment options have been developed for neovascular age-related macular degeneration (AMD), the most notable being...
Background and objectives Over the years, several treatment options have been developed for neovascular age-related macular degeneration (AMD), the most notable being intravitreal injections of anti-vascular endothelial growth factor drugs. The rationale for treating neovascular AMD is to preserve and improve central vision, enhance the quality of life for affected individuals, stabilize or improve vision, and prevent further structural damage to the macula. The objective of the present study was to evaluate the clinical course of different disease types of neovascular age-related macular degeneration and their treatment response to anti-vascular endothelial growth factor (anti-VEGF) injections. Methods This prospective observational study was conducted at a tertiary care referral hospital in Eastern India during October 2019 and September 2021. Patients diagnosed with neovascular AMD attending our Outpatient department and retina clinic were recruited for the study. An experienced ophthalmologist examined all patients, meeting the inclusion criteria. The clinical profile, including initial best corrected visual acuity (BCVA), ophthalmoscopic, fluorescein angiographic, and optical coherence tomography (OCT) findings of different patterns of neovascular AMD, were collected and analyzed. Patients were subjected to intravitreal Ranibizumab every month for three months and then on a when-required basis. Visual outcomes were recorded at each follow-up, and a comparison was done between initial and final visual acuity. Descriptive statistics were used for analysis, with p< 0.05 taken as statistically significant. Results A total of 72 patients were included in the study. Fundus fluorescein angiography revealed that 52.78% were classic, 15.28% were minimally classic, and 31.94% were of occult variety. 41.66% of lesions were subfoveal in location, 47.22% were juxtafoveal, and 11.11% lesions were extrafoveal in location. The mean BCVA was Log MAR (Logarithm of the Minimum Angle of Resolution) 1.061±0.25. The average number of intravitreal Ranibizumab injections given to each eye was five. BCVA of patients after the third injection was log MAR 0.818±0.296. There was a significant improvement in mean BCVA from baseline 1.061±0.254 to 0.787±0.317 after the study (p-valve: p<0.05). After the first injection, 49 patients (68.05%) experienced an initial improvement of at least one line, 20 patients (27.77%) did not exhibit any improvement, and 3 patients (4.16%) had a decline of one line in Snellen's visual acuity chart. Over the follow-up period,10 showed improvement in 1 line in the Snellen chart after subsequent injection. At the end of the study, six patients showed no change, and four patients showed deterioration after the completion of injections. No adverse events were noted during the study period. Conclusions Intravitreal Ranibizumab is effective in improving visual outcomes in treatment-naïve individuals with neovascular age-related macular degeneration. The decision for repeat intravitreal anti-VEGF injection should be based on OCT findings of subretinal fluid, pigment epithelial detachment, and cystoid macular edema as an indicator of disease activity. This can also lessen the number of intravitreal injections and morbidity in these patients.
PubMed: 38384637
DOI: 10.7759/cureus.52731 -
The Journal of Experimental Biology Mar 2024Previous studies often inferred the focus of a bird's attention from its head movements because it provides important clues about their perception and cognition....
Previous studies often inferred the focus of a bird's attention from its head movements because it provides important clues about their perception and cognition. However, it remains challenging to do so accurately, as the details of how they orient their visual field toward the visual targets remain largely unclear. We thus examined visual field configurations and the visual field use of large-billed crows (Corvus macrorhynchos Wagler 1827). We used an established ophthalmoscopic reflex technique to identify the visual field configuration, including the binocular width and optical axes, as well as the degree of eye movement. A newly established motion capture system was then used to track the head movements of freely moving crows to examine how they oriented their reconstructed visual fields toward attention-getting objects. When visual targets were moving, the crows frequently used their binocular visual fields, particularly around the projection of the beak-tip. When the visual targets stopped moving, crows frequently used non-binocular visual fields, particularly around the regions where their optical axes were found. On such occasions, the crows slightly preferred the right eye. Overall, the visual field use of crows is clearly predictable. Thus, while the untracked eye movements could introduce some level of uncertainty (typically within 15 deg), we demonstrated the feasibility of inferring a crow's attentional focus by 3D tracking of their heads. Our system represents a promising initial step towards establishing gaze tracking methods for studying corvid behavior and cognition.
Topics: Animals; Crows; Eye-Tracking Technology; Motion Capture; Vision, Ocular; Visual Fields
PubMed: 38362616
DOI: 10.1242/jeb.246514 -
International Journal of Circumpolar... Dec 2024Retina fundus images conducted in Greenland are telemedically assessed for diabetic retinopathy by ophthalmological nurses in Denmark. Applying an AI grading solution,...
Retina fundus images conducted in Greenland are telemedically assessed for diabetic retinopathy by ophthalmological nurses in Denmark. Applying an AI grading solution, in a Greenlandic setting, could potentially improve the efficiency and cost-effectiveness of DR screening. We developed an AI model using retina fundus photos, performed on persons registered with diabetes in Greenland and Denmark, using Optos® ultra wide-field scanning laser ophthalmoscope, graded according to ICDR.Using the ResNet50 network we compared the model's ability to distinguish between different images of ICDR severity levels in a confusion matrix. Comparing images with ICDR level 0 to images of ICDR level 4 resulted in an accuracy of 0.9655, AUC of 0.9905, sensitivity and specificity of 96.6%.Comparing ICDR levels 0,1,2 with ICDR levels 3,4, we achieved a performance with an accuracy of 0.8077, an AUC of 0.8728, a sensitivity of 84.6% and a specificity of 78.8%. For the other comparisons, we achieved a modest performance. We developed an AI model using Greenlandic data, to automatically detect DR on Optos retina fundus images. The sensitivity and specificity were too low for our model to be applied directly in a clinical setting, thus optimising the model should be prioritised.
Topics: Humans; Artificial Intelligence; Diabetic Retinopathy; Diabetes Mellitus; Sensitivity and Specificity; Greenland; Mass Screening
PubMed: 38359160
DOI: 10.1080/22423982.2024.2314802 -
Optics Express Jan 2024We propose and design a multi-stage cascaded scanning laser ophthalmoscope (SLO) for ultra-wide field (UWF), which uses conicoid mirrors, constructed by conjugation of...
We propose and design a multi-stage cascaded scanning laser ophthalmoscope (SLO) for ultra-wide field (UWF), which uses conicoid mirrors, constructed by conjugation of pupil plane. The vergence uniformity and the angular magnification of a cascaded conicoid mirrors (CCM) system are analyzed recursively and optimized preliminarily to achieve high quality imaging with UWF, and the optimal system with the model eye are obtained by simulation and optimization. Two-stage and three-stage cascaded systems are designed with this method, and the formulas of beam vergence and angular magnification are obtained by theoretical derivation. As compared to the two-stage CCM system, the proposed three-stage cascaded UWF SLO has superior performance in imaging quality. Its average RMS radius of spot diagram is calculated to be 26.372 µm, close to the diffractive limit resolution. The image resolution of human retina can be up to 30 µm with 135° FOV in theory. The three-stage cascaded SLO is more suitable for UWF fundus imaging. This study will be helpful for early screening and accurate diagnosis of various diseases in the peripheral retina.
Topics: Humans; Ophthalmoscopy; Fundus Oculi; Retina; Ophthalmoscopes; Lasers
PubMed: 38297535
DOI: 10.1364/OE.508121 -
Journal of Ophthalmic & Vision Research 2023This study aimed to report a case of peripapillary choroidal neovascularization (CNV) with a pitchfork sign.
PURPOSE
This study aimed to report a case of peripapillary choroidal neovascularization (CNV) with a pitchfork sign.
CASE REPORT
A young female presented with a progressive and painless visual blurring of the left eye. Ophthalmoscopic findings and results of optical coherence tomography (OCT), OCT angiography (OCTA), and fluorescein angiography (FAG) were evaluated. OCT showed subretinal hyperreflective material adjacent to the optic nerve head with multiple vertical finger-like projections extending into the outer retina (pitchfork sign). OCTA revealed that seafan-shaped high-flow vessels above the retinal pigment epithelium (RPE) were compatible with CNV type 2 with a large feeder vessel completely contiguous with the optic nerve. No evidence of ocular or systemic inflammation was found.
CONCLUSION
Pitchfork sign can be seen in CNV type 2 in either inflammatory or noninflammatory conditions.
PubMed: 38250232
DOI: 10.18502/jovr.v18i4.14557 -
BioMed Research International 2024[This retracts the article DOI: 10.1155/2022/5422360.].
[This retracts the article DOI: 10.1155/2022/5422360.].
PubMed: 38230043
DOI: 10.1155/2024/9820545 -
BMC Ophthalmology Jan 2024To investigate the relationship between body weight and Axial length in guinea pigs.
BACKGROUND
To investigate the relationship between body weight and Axial length in guinea pigs.
METHODS
Forty pigmented guinea pigs were randomly divided into two groups, namely control group and negative lens-induced myopization (LIM) group. After measuring the baseline axial length and body weight (BW), guinea pigs of LIM group received bilateral negative lens-induced myopization using - 10.0 diopters lenses. One week later, the lenses were removed and biometric and ophthalmoscopic examinations were repeated.
RESULTS
Two groups of guinea pigs showed no statistical difference in initial body weight and eye axis length. Compared to the control group, the lens-induced group had a lower weight (P = 0.02) and a longer axial length (P < 0.01) at the end of study Neither at baseline nor at week 1 did AL correlate with BW in both groups (Control Baseline: r = 0.306, P = 0.19; Control Week1: r = 0.333, P = 0.15; LIM Baseline: r=-0.142, P = 0.55; LIM Week 1: r = 0.189, P = 0.42). Lens-induction had a significant effect on axial elongation (P < 0.01) while body weight had no impact on such aspect (P > 0.05).
CONCLUSION
In guinea pigs of the same age, axial length was not correlated with body weight. Also, baseline body weight had no impact on natural axial length growth or lens-induced myopia. Lens-induction caused a significant reduction in body weight gain.
Topics: Animals; Guinea Pigs; Myopia; Lens, Crystalline; Axial Length, Eye; Biometry; Disease Models, Animal
PubMed: 38172796
DOI: 10.1186/s12886-023-03271-y -
Diagnostics (Basel, Switzerland) Dec 2023Age-related macular degeneration (AMD) is a leading cause of blindness worldwide. In late-stage AMD, geographic atrophy (GA) of dry AMD or choroidal neovascularization... (Review)
Review
Age-related macular degeneration (AMD) is a leading cause of blindness worldwide. In late-stage AMD, geographic atrophy (GA) of dry AMD or choroidal neovascularization (CNV) of neovascular AMD eventually results in macular atrophy (MA), leading to significant visual loss. Despite the development of innovative therapies, there are currently no established effective treatments for MA. As a result, early detection of MA is critical in identifying later central macular involvement throughout time. Accurate and early diagnosis is achieved through a combination of clinical examination and imaging techniques. Our review of the literature depicts advances in retinal imaging to identify biomarkers of progression and risk factors for late AMD. Imaging methods like fundus photography; dye-based angiography; fundus autofluorescence (FAF); near-infrared reflectance (NIR); optical coherence tomography (OCT); and optical coherence tomography angiography (OCTA) can be used to detect and monitor the progression of retinal atrophy. These evolving diverse imaging modalities optimize detection of pathologic anatomy and measurement of visual function; they may also contribute to the understanding of underlying mechanistic pathways, particularly the underlying MA changes in late AMD.
PubMed: 38132220
DOI: 10.3390/diagnostics13243635 -
Eye (London, England) Apr 2024This study aimed to compare a new Artificial Intelligence (AI) method to conventional mathematical warping in accurately overlaying peripheral retinal vessels from two...
PURPOSE
This study aimed to compare a new Artificial Intelligence (AI) method to conventional mathematical warping in accurately overlaying peripheral retinal vessels from two different imaging devices: confocal scanning laser ophthalmoscope (cSLO) wide-field images and SLO ultra-wide field images.
METHODS
Images were captured using the Heidelberg Spectralis 55-degree field-of-view and Optos ultra-wide field. The conventional mathematical warping was performed using Random Sample Consensus-Sample and Consensus sets (RANSAC-SC). This was compared to an AI alignment algorithm based on a one-way forward registration procedure consisting of full Convolutional Neural Networks (CNNs) with Outlier Rejection (OR CNN), as well as an iterative 3D camera pose optimization process (OR CNN + Distortion Correction [DC]). Images were provided in a checkerboard pattern, and peripheral vessels were graded in four quadrants based on alignment to the adjacent box.
RESULTS
A total of 660 boxes were analysed from 55 eyes. Dice scores were compared between the three methods (RANSAC-SC/OR CNN/OR CNN + DC): 0.3341/0.4665/4784 for fold 1-2 and 0.3315/0.4494/4596 for fold 2-1 in composite images. The images composed using the OR CNN + DC have a median rating of 4 (out of 5) versus 2 using RANSAC-SC. The odds of getting a higher grading level are 4.8 times higher using our OR CNN + DC than RANSAC-SC (p < 0.0001).
CONCLUSION
Peripheral retinal vessel alignment performed better using our AI algorithm than RANSAC-SC. This may help improve co-localizing retinal anatomy and pathology with our algorithm.
Topics: Humans; Artificial Intelligence; Retina; Retinal Vessels; Algorithms; Neural Networks, Computer
PubMed: 38114568
DOI: 10.1038/s41433-023-02868-3 -
BMJ Open Ophthalmology Dec 2023Colour scanning laser ophthalmoscope (cSLO) offers several advantages, including improved image quality and better visualisation of the retinal structures compared with...
OBJECTIVE
Colour scanning laser ophthalmoscope (cSLO) offers several advantages, including improved image quality and better visualisation of the retinal structures compared with colour fundus photograph (CFP). This study aimed to identify whether cSLO could be used to predict systemic arterial stiffness.
METHODS AND ANALYSIS
We retrospectively analysed the data of 54 patients with 103 eyes. In addition to blood pressure and blood data, all patients had cardio-ankle vascular index (CAVI) measurements, as well as images of the fundus acquired using cSLO and CFP. We determined the retinal artery sclerosis (RAS) index from the colour of the retinal artery in cSLO images, the ratio of arterial to venous diameter (A/V ratio), and Scheie's classification in CFP images. The correlation between each parameter and CAVI was examined using Spearman's rank correlation coefficient, and the correlation between Scheie's classification and CAVI was examined using Steel-Dowass tests.
RESULTS
CAVI showed a significant positive correlation with the RAS index (r=0.679, p<0.001) but not with the A/V ratio or Scheie's classification. Multiple regression analysis showed that the RAS index was significantly and independently correlated with CAVI.
CONCLUSION
cSLO is a non-invasive imaging modality that has the potential to accurately and instantaneously detect early systemic arterial stiffness.
Topics: Humans; Arterioles; Retrospective Studies; Vascular Stiffness; Color; Ophthalmoscopes; Lasers
PubMed: 38057107
DOI: 10.1136/bmjophth-2023-001456