AIM: To evaluate the peripheral arterial filling time (PAFT) and venous filling time (VFT) in eyes without known diseases that may influence filling process using ultra-widefield (UWF) fluorescein angiography (FA), and to review the peripheral retina fluorescence features. METHODS: A total of 30 eyes of 30 patients were retrospectively reviewed in this observational study. UWF-FA was performed using Optos 200Tx. PAFT and VFT was recorded. The interval between the arterial or venous filling completion and the previous photo was documented. The appearance of the far peripheral retina was described as either granular background fluorescence or mottled fluorescent band or vascular leakage. Terminal vascular patterns was described as loop pattern or branching pattern. Microvascular abnormalities such as arteriovenous shunting, vessels crossing the horizontal raphe, right angle vessels, terminal networks, capillary nonperfusion, drusen or microaneurysms were evaluated. RESULTS: The normal limits of PAFT was 3.397-8.984s and 4.399-11.753s for VFT. The appearance of the far peripheral retina, defined as granular background (63%), mottled fluorescence (20%), or vascular leakage (17%), was symmetrical between both eyes. Capillary nonperfusion (23%) and microaneurysms (40%) were more frequently found in eyes with loop pattern than in eyes with branching pattern. Other peripheral signs such as right-angle vessels (73%), and terminal networks (80%) were commonly seen on UWF-FA in the normal peripheral retina. CONCLUSION: The main courses of retinal artery and vein filling time are overlapping with each other on UWF-FA. Notably, the arterial filling process is completed in the arteriovenous phase rather than the traditionally named arterial phase. There are various manifestations in the peripheral retina of normal eyes.

Objectives: To descriptively evaluate the feasibility and clinical utility of TowardPi BO (4K ultra HD microscope integrated with a 400 kHz swept-source intraoperative optical coherence tomography (SS-iOCT) system) in managing various ophthalmic surgical conditions in a real-world setting. Methods: We analyzed surgical videos and data from 123 consecutive cases that underwent elective surgery with the assistance of this SS-iOCT system at Beijing Tongren Hospital between September 2, 2025, and February 10, 2026. Surgical cases were included based on specific diagnoses for which the SS-iOCT was found to be demonstrably useful. All videos were reviewed, and the utility of iOCT was discussed. Results: A total of 72 surgical cases were included, comprising 7 intraocular lens implantations with ciliary sulcus fixation, 19 macular holes, 3 cases of macular hole retinal detachment (MHRD), 4 cases of macular schisis with or without foveal detachment (MSRD), 12 cases of submacular hemorrhage, 20 cases of rhegmatogenous retinal detachment (RRD), and 7 intraocular mass lesions. The 400 kHz SS-iOCT significantly aided in surgical visualization, guided real-time decision-making, and prompted modifications in surgical techniques. Conclusions: This study presents the first report on 400 kHz SS-iOCT application in intraocular tumors. From routine surgical teaching to complex case management, SS-iOCT enhances surgical precision and facilitates real-time decision-making, ultimately contributing to improved surgical outcomes.

Objectives: We aimed to descriptively evaluate the feasibility and clinical utility of TowardPi BO (4K ultra-HD microscope integrated with a 400 kHz swept-source intraoperative optical coherence tomography (SS-iOCT) system) in managing various ophthalmic surgical conditions in a real-world setting. Methods: We analyzed surgical videos and data from 123 consecutive cases that underwent elective surgery with the assistance of this SS-iOCT system at Beijing Tongren Hospital between 2 September 2025 and 10 February 2026. Cases were included when the iOCT provided critical, real-time information that directly influenced surgical decision-making or technique modification. Cases were excluded if iOCT served only routine confirmatory or educational purposes without altering the surgical plan. Results: A total of 72 surgical cases were included, comprising 7 intraocular lens implantations with ciliary sulcus fixation, 19 macular holes, 3 cases of macular hole retinal detachment (MHRD), 4 cases of macular schisis with or without foveal detachment (MSRD), 12 cases of submacular hemorrhage, 20 cases of rhegmatogenous retinal detachment (RRD), and 7 intraocular mass lesions. The 400 kHz SS-iOCT significantly aided in surgical visualization, guided real-time decision-making, and prompted modifications in surgical techniques. Conclusions: To our knowledge, this is the first real-world study to evaluate the application of a 400 kHz SS-iOCT system across a wide spectrum of ophthalmic conditions, including its novel use in intraocular tumors. From routine to complex surgical cases, SS-iOCT enhances surgical precision and facilitates real-time decision-making, ultimately contributing to improved surgical outcomes.