Vascular perfusion distribution in fibroids contrast-enhanced ultrasound images provides useful pathological and physiological information, because the extraction of the vascular perfusion area can be helpful to quantitative evaluation of uterine fibroids blood supply. The pixel gray scale in vascular perfusion area of fibroids contrast-enhanced ultrasound image sequences is different from that in other regions, and, based on this, we proposed a method of extracting vascular perfusion area of fibroids. Firstly, we denoised the image sequence, and then we used Brox optical flow method to estimate motion of two adjacent frames, based on the results of the displacement field for motion correction. Finally, we extracted vascular perfusion region from the surrounding background based on the differences in gray scale for the magnitude of the rich blood supply area and lack of blood supply area in ultrasound images sequence. The experimental results showed that the algorithm could accurately extract the vascular perfusion area, reach the precision of identification of clinical perfusion area, and only small amount of calculation was needed and the process was fairly simple.
ObjectiveTo compare the quantitative measurements of the retinal capillary nonperfusion areas in a cohort of proliferative diabetic retinopathy (PDR) patients with fluorescein fundus angiography (FFA) and swept source optical coherence tomography angiography (SS-OCTA), and to determine the intrapersonal variability between examiners.MethodsA cross-sectional study. Eighteen eyes of eleven PDR patients diagnosed in Department of ophthalmology of Henan Provincial People's Hospital from September 2019 to January 2020 were included in this study. FFA was performed using Spectralis HRA+OCT (Germany Heidelberg Company) from and SS-OCTA was performed using VG200D (China Vision Micro Image Corporation). SS-OCTA was used to collect images of retinal layer, superficial capillary plexus (SCP) and deep capillary plexus (DCP). The same observation area was 80°×60° for SS-OCTA and 55° for FFA with both setting centered on the fovea. The forty-nine retinal capillary nonperfusion areas were observed. The area measurement was completed independently by three examiners. Paired sample t test or paired sample Wilcoxon test were used to compare the measured values of retinal capillary nonperfusion areas between the two examination methods and among the three examiners.ResultsThere was no significant difference in the retinal layer, SCP and DCP nonperfusion area measured by FFA and SS-OCTA among the three examiners (P＞0.05), and the consistency is good (consistency correlation coefficient＞0.9, P＜0.05). The nonperfusion area measured by FFA was 0.786 mm2. The median nonperfusion area of retinal layer and SCP measured by SS-OCTA were 0.787 mm2 and 0.791 mm2, respectively, and the average nonperfusion area of DCP was 0.878±0.366 mm2. The nonperfusion area of retinal layer and SCP measured by FFA and SS-OCTA showed no statistically significant difference (P=0.054, 0.198). The nonperfusion area of DCP measured by SS-OCTA was significantly larger than that of FFA, and the difference was statistically significant (P＜0.001). The results of repeatability analysis showed that 93.88% (46/49) of the DCP nonperfusion area data measured by SS-OCTA were greater than those measured by FFA.ConclusionThe retinal nonperfusion area of DCP in PDR patients measured by SS-OCTA is larger than that of FFA.
With the wide popularization of low-dose computed tomography screening for lung cancer, the proportion of early detection of lung cancer has increased significantly. Due to the favorable prognosis of ground-glass nodule-lung cancer, a prospective multicenter clinical trial in Japan has confirmed the safety and efficacy of segmentectomy. Identification of the intersegmental plane is one of the key steps in segmentectomy. Understanding its physiological mechanism can provide a theoretical basis for optimizing the identification technique, identifying intersegmental plane more accurately and quickly, improving the surgical effect and reducing complications. This article mainly introduces the identification technology of the intersegmental plane and its physiological mechanism in pulmonary segmentectomy.