Background: Microvascular rarefaction due to hypertension has been linked to disease severity and end-organ complications. Optical coherence tomography angiography (OCTA) has been explored as a potential tool to evaluate the retinal microvascular network in hypertensive patients. Methods: PubMed, Scopus, Web of Science, and Cochrane were systematically searched to 10th of September of 2021, along with a manual search. Studies that used OCTA as a primary diagnostic method to evaluate the macular microvasculature of hypertensive patients were included. Meta-analysis was performed using a random-effects model. Primary outcomes were macular vessel density (VD) and foveal avascular zone (FAZ) at the superficial and deep capillary plexus. Results: Of 947 screened articles, 9 were found eligible for qualitative and quantitative analysis. VD in hypertensive patients was reduced when compared with controls in the fovea (0.93, 95% confidence interval [CI] 0.87–0.99, P = 0.023) and the parafovea (0.95, 95% CI 0.93–0.97, P < 0.001) of the superficial capillary plexus. FAZ was larger in the deep plexus of hypertensive patients (1.10, 95% CI 1.03–1.18, P = 0.003). VD reduction was found in patients with worsening blood pressure control in 3 studies and prolonged disease in 2 studies. Conclusions: Microvascular rarefaction of the macula is found in hypertensive patients with a reduction of foveal and parafoveal VD and an increase of FAZ area. Disease duration and severity might be related to a microvascular rarefaction. OCTA could offer a novel tool for the assessment and follow-up of hypertensive patients.

The purpose of this study is to evaluate the macular ganglion cell layer (GCL) and peripapillary retinal nerve fibre layer (RNFL) thickness in patients with unilateral posterior cerebral artery (PCA) ischaemic lesions using spectral-domain optical coherence tomography (SD-OCT). A prospective, case-control study of patients with unilateral PCA lesion was conducted in the neuro-ophthalmology clinic of Centro Hospitalar Lisboa Central. Macular and peripapillary SD-OCT scans were performed in both eyes of each patient. Twelve patients with PCA lesions (stroke group) and 12 healthy normal controls were included in this study. Peripapillary RNFL comparison between both eyes of the same subject in the stroke group found a thinning in the superior-temporal (p = 0.008) and inferior-temporal (p = 0.023) sectors of the ipsilateral eye and nasal sector (p = 0.003) of the contralateral eye. Macular GCL thickness comparison showed a reduction temporally in the ipsilateral eye (p = 0.004) and nasally in the contralateral eye (p = 0.002). Peripapillary RNFL thickness was significantly reduced in both eyes of patients with PCA compared with controls, affecting all sectors in the contralateral eye and predominantly temporal sectors in the ipsilateral eye. A statistically significant decrease in macular GCL thickness was found in both hemiretinas of both eyes of stroke patients when compared with controls (p < 0.05). This study shows that TRD may play a role in the physiopathology of lesions of the posterior visual pathway.

Eye diseases, such as glaucoma, diabetic retinopathy, and age-related macular degeneration, drive the growing need for reliable and scalable analyses of fundus and optical coherence tomography (OCT) images. Deep learning performs strongly in ocular structure segmentation. However, it typically relies on dense pixel-wise annotations, which are costly and difficult to obtain at scale. Weakly supervised learning (WSL) can reduce this burden by leveraging coarse labels, limited strong annotations, and unlabeled data. This systematic umbrella review synthesizes survey and review articles on weakly supervised deep learning for image segmentation, with a focus on ocular imaging (fundus and OCT/OCTA). After analyzing twenty-one secondary studies, the main finding reveals an “empty intersection”: WSL-focused segmentation surveys are often modality-agnostic. Conversely, ocular reviews are predominantly fully supervised and seldom offer quantitative evidence on annotation-effort savings or direct comparisons between weak and fully supervised methods on identical datasets. Across the included reviews, label-efficient strategies cluster around CAM/MIL formulations, sparse supervision (points/scribbles/boxes), pseudo-labelling/self-training, and semi-/self-supervised learning, implemented mainly with U-Net/DeepLab families and increasingly Transformer or hybrid backbones. These results provide a structured map of available WSL mechanisms and, critically, identify reproducible reporting gaps that currently prevent fair benchmarking in ocular segmentation. Therefore, this review supports the development of ocular-specific benchmarks and minimum reporting practices that link segmentation performance to annotation effort.

1. Inherited retinal diseases (IRDs) are a clinically and genetically heterogeneous group of disorders that often result in progressive vision loss with the potential for complete blindness at the ...