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oe1(光电查) - 科学论文

2 条数据
?? 中文(中国)
  • Comparative Study of Optical Coherence Tomography Angiography and Phase-Resolved Doppler Optical Coherence Tomography for Measurement of Retinal Blood Vessels Caliber

    摘要: Purpose: To compare the accuracy of Doppler optical coherence tomography (DOCT) and OCT angiography (OCTA) for measuring retinal blood vessel caliber at different flow rates. Methods: A research-grade 1060-nm OCT system with 3.5-lm axial resolution in retinal tissue and 92,000 A scan/s image acquisition rate was used in this study. DOCT and OCTA measurements were acquired both from a flow phantom and in vivo from retinal blood vessels in six male Brown Norway rats. The total retinal blood flow (TRBF) was modified from baseline to 70% and 20% of baseline by reducing the ocular perfusion pressure (OPP). The retinal blood vessel caliber (RBVC) was measured from OCTA and DOCT images. The caliber measurements were conducted by two separate graders using a custom MATLAB-based image processing algorithm. Results: The RBVC measured with OCTA and DOCT for normal blood flow rates were not significantly different (56.69 6 12.17 and 57.17 6 9.46 lm, P ? 0.27, respectively). However, significant differences were detected when TRBF was reduced to 70% (55.69 6 11.56 vs. 50.62 6 8.85 lm, P , 0.01) and 20% (50.29 6 9.29 vs. 44.88 6 7.13 lm, P , 0.01) of baseline. Conclusions: Reduced TRBF resulted in inaccuracy of the RBVC measurements with DOCT in both the phantom and animal study. This result suggests that OCTA is a more accurate tool for RBVC evaluation when applied to retinal diseases associated with reduced TRBF, such as glaucoma and diabetic retinopathy. Translational Relevance: Results from this study are directly applicable to clinical studies of retinal blood flow measured with OCTA and DOCT.

    关键词: optical coherence tomography angiography,ocular perfusion pressure,retinal imaging,doppler optical coherence tomography

    更新于2025-09-23 15:22:29

  • Comparison of Neurovascular Coupling between Normal Tension Glaucoma Patients and Healthy Individuals with Laser Speckle Flowgraphy

    摘要: Background The purpose of this pilot study was to investigate the differences in neurovascular coupling between Caucasian patients with normal tension glaucoma (NTG) and healthy subjects (HS) with Laser Speckle Flowgraphy (LSFG). Methods Measurement of optic nerve head blood flow was performed with LSFG. Mean blur rate of the whole optic nerve head (MA), of the big retinal vessels (MV) and of the microvasculature (MT) was analysed during continuous flicker light stimulation for four minutes. Results We included 12 eyes from 12 Caucasian patients with diagnosis of normal tension glaucoma and 12 eyes from 12 age- and sex-matched healthy individuals. MA, MV and MT all increased significantly in both groups during the observation period with no difference between the groups. Conclusion Neurovascular coupling is detectable in NTG patients. Flicker light stimulation leads to a comparable increase in ocular blood flow in glaucoma patients and healthy individuals.

    关键词: flicker,laser speckle flowgraphy,ocular perfusion,normal tension glaucoma,neurovascular coupling

    更新于2025-09-19 17:13:59