Purpose To compare the lesion sizes of choroidal neovascularization (CNV) imaged with spectral-domain (SD) and swept-source (SS) optical coherence tomography angiography (OCTA) and measured using an automated detection algorithm. recognized between manual and automatic measurements: SD-OCTA 3 3-mm (= 0.61, paired = 0.09, combined = 0.41, paired = 0.16, paired = 0.011, paired sample = 0.021, paired > 0 and are the gain and bias guidelines, controlling contrast and brightness, respectively. In this QS 11 study, = 0.5 and = 100 for both the systems based on the OCT system signal-to-noise percentage and signal strength, which results in a contrast-enhanced image (Fig. 2B). Next, the producing image (Fig. 2B) was low-pass filtered to remove noise through a convolution operation: QS 11 where = 5 was used in this study. Otsu’s adaptive threshold method30 was consequently applied to produce a binary image (Fig. 2C) from which the neovascular border/contour format (Fig. 2D) was extracted by morphologic dilation followed by the Canny edge detection.31 The neovascular lesion size was calculated by summing the areas of the pixels within the region bounded from the contour collection (Fig. 2E). Number 2 Flow chart of the automated algorithm to section the choroidal neovascularization (CNV). (A) The artifact-free ORCC angiogram. (B) Image contrast of the ORCC angiogram is definitely enhanced through an adaptive thresholding method. (C) Binary image is definitely acquired through … Choroidal neovascularization lesion size was measured by using this algorithm on en face ORCC angiograms from both SD-OCTA and SS-OCTA tools. In addition, two graders (JROD and ZY), masked to instrument type that was used to acquire the image, manually defined the CNV lesions from your same artifact-free ORCC angiograms and determined the related lesion sizes. Neither of the graders examined the images prior to grading. QS 11 The two units of measurements were analyzed and compared in order to validate our automated algorithm. Statistical Analysis Combined sample ideals below 0.05 were considered statistically significant. Results Images from 27 eyes of 23 individuals were available for QS 11 this QS 11 study, as described in our friend paper.34 For each of these eyes, both the 3 3- and 6 6-mm scans from your SD-OCTA and from your SS-OCTA device were analyzed. Assessment Between Automatic and Manual Measurements Table 1 summarizes the comparisons between the manual and automated measurements from the two tools. No significant variations were found between automatic and manual measurements for both tools using the 3 3-mm scans (= 0.41 and 0. 61 for SS-OCTA and SD-OCTA, respectively; paired sample = 0.16 and 0.09 for SS-OCTA and SD-OCTA, respectively; paired sample represents the imply difference, and … Comparisons Between Two Products Figure 5 shows examples of the automated segmentation of lesion from 3 3- and 6 6-mm scans. For both the devices, the 3 3-mm angiograms delivered clearer visualization of the CNV with better contrast and image quality. Swept-source OCTA angiograms offered a better overall signal-to-noise percentage and higher vascular details compared with SD-OCTA. Number 5 Automated measurements of choroidal neovascularization (CNV) based on artifact-free ORCC angiograms using both 3 3- and 6 6-mm scans acquired using SS-OCTA (= 0.011, paired sample = 0.021, paired sample < 0.001 and = 0.013 and = 0.011 for 3 3 mm and = 0.021 for 6 6 mm, paired sample t-test). There was a statistically significant correlation between SD-OCTA and SS-OCTA measurements for both types of scans. However, the SS-OCTA scans produced consistently larger lesion sizes. This result appears to indicate that SS-OCTA might be able to visualize and measure more of the CNV compared with SD-OCTA Rabbit Polyclonal to PLG. imaging. This is consistent with the expected theoretical advantages of the SS-OCT system. In particular, the use of a 1050-nm wavelength in the SS-OCTA instrument reduces the optical scattering and absorption from your RPE complex and allows for the safe use of higher laser power, resulting in increased transmission from constructions below the RPE, including type 1 CNV. Moreover, SS-OCT systems have the advantage of a smaller sensitivity roll-off compared with SD-OCT.35 These considerations should lead to better results when imaging CNV using SS-OCTA and would clarify larger lesion area measurements, once we found both using manual segmentations and our automated algorithm. The variations between the SS-OCTA and SD-OCTA manual and automated measurements of CNV for the 6 6- and 3 3-mm scans were statistically significant. This may be explained from the.