Quantitative evaluation of primary retinitis pigmentosa patients using colour Doppler flow imaging and optical coherence tomography angiography

Abstract

Purpose To find the potential relation between changes in retinal large vessels and terminal vessels using colour Doppler flow imaging (CDFI) and optical coherence tomography angiography (OCTA) and to compare the respective advantages of CDFI and OCTA in evaluating vascular changes in retinitis pigmentosa (RP) patients. Methods A prospective series of case study was conducted to enrol RP patients and age‐matched controls, who were, respectively, imaged by CDFI and OCTA. Repeatability and reproducibility of both CDFI and OCTA were performed among healthy volunteers. The central retinal artery (CRA) was detected by CDFI analysis to provide parameters of peak systolic velocity (PSV), end‐diastolic velocity (EDV) and time‐averaged maximum velocity (TAMV). Retinal parameters were evaluated from OCTA images, including vascular area density (VAD) of the superficial vascular layer, the fovea avascular zone (FAZ) area and retinal thickness. RP patients were separated into a high‐vision group and a low‐vision group, according to median vision (0.3, LogMAR 0.5). Multiple comparisons were used to analyse the data between groups. A correlation analysis was used to determine the correlation between CDFI and OCTA parameters. Results Twenty RP patients (40 eyes) and thirteen normal volunteers (26 eyes) were enrolled in this study. Repeatability and reproducibility of the measurements by CDFI had higher CVs, from 4.5% to 15.4%, than those measurements by OCTA (<5%). All the CDFI and OCTA parameters examined had significant reductions in RP patients compared to those in the controls (p < 0.01). Compared to the high‐vision group, the low‐vision group exhibited a statistically significant decrease in vascular parameters of the FAZ area, fovea VAD and parafovea nasal side VAD (p < 0.05); as well as in the parameters of the fovea thickness, and the parafovea nasal, superior and inferior side thickness (p < 0.05). From the correlation analysis, a significant association was found between the vision and CDFI parameters (PSV and time‐averaged maximum velocity (TAMX), p < 0.05), and the vision and OCTA parameters (FAZ area, fovea and nasal side VAD, retinal thickness in all sides, p < 0.05). PSV and TAMX of the CRA were closely related to the OCTA superficial VAD in all sides, whereas the CDFI parameters showed poor correlation with retinal thickness. Conclusions Colour Doppler flow imaging (CDFI) and OCTA parameters revealed a significant reduction in RP patients when compared to the controls. OCTA can detect vision‐related microvascular and thickness changes around the macula between high‐ and low‐vision groups, which happen earlier than the changes in large vessels. In addition to good repeatability and reproducibility, OCTA may have significant utility in the diagnosis and monitoring of disease progression in RP patients.

Optical Coherence Tomography Angiography Imaging in Inherited Retinal Diseases

“…Significant associations between visual acuity and parafoveal flow density in the superficial [29,32] and deep retinal layer [31,32], foveal flow density in the superficial retinal layer [32,35], and superficial FAZ [31,32,35] have also been reported. Correlations between superficial and deep capillary plexus vessel densities with multifocal electroretinogram values and ganglion cell complex layer thickness have also been shown [30].…”

“…Takagi et al examined flow area in both the superficial and deep capillary plexus and similarly showed that these parameters were lower in RP eyes vs. controls [34]. Wang and colleagues examined the foveal and parafoveal subfields and found that the vessel area densities in the superficial capillary plexus in all subfields in RP eyes were lower than in control eyes [35].…”

“…In addition, many groups have also examined foveal avascular zone (FAZ) size, and most agree that the FAZ area is larger in RP eyes when compared to controls [29,31,33,35]. Notably, Battaglia Parodi et al and Takagi et al examined the FAZ in the superficial and deep capillary plexuses separately, and while Battaglia Parodi and coauthors found that the deep FAZ but not the superficial FAZ is larger in RP eyes [28], Takagi et al found that the superficial but non-deep FAZ is larger in RP eyes [34].…”

Diagnostic accuracy of ultrasound superb microvascular imaging for breast tumor: a meta-analysis

“…The shape and distribution of neovascularization in tumors are related to the aggressive growth pattern of cancer cells, which is helpful to distinguish the nature of the tumor [5]. Color Doppler flow imaging (CDFI) is often used to show the blood flow inside the tumor, but CDFI can provide limited data in some low-velocity microvessels [6]. As a novel US technique, Superb Microvascular Imaging (SMI) can quickly, simply and noninvasively study the microvascular distribution in the tumor and evaluate the microvascular perfusion [7].…”

The value of TI-RADS combined with superb micro-vascular imagine in distinguishing benign and malignant thyroid nodules:a meta-analysis

“…There are some differences between benign and malignant thyroid nodules in blood ow pattern and vascular morphology, which is helpful to distinguish benign and malignant thyroid nodules [6]. Color Doppler ow imaging (CDFI) is often used to show the blood ow inside the tumor, but CDFI is not good for some low-velocity microvessels [7]. As a novel ultrasonic technique, SMI can quickly, simply and noninvasively observe the microvascular distribution in the tumor and evaluate the microvascular perfusion [8].…”