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Synthetic Aperture Radar Interferometry (InSAR), which can map subtle ground displacement over large areas, has been widely utilized to recognize active landslides. Nevertheless, due to various origins of subtle ground displacement, their presence on slopes may not always reflect the occurrence of active landslides. Therefore, interpretation of exact landslide-correlated deformation from InSAR results can be very challenging, especially in mountainous areas, where natural phenomenon like soil creep, anthropogenic activities and erroneous deformational signals accumulated during InSAR processing can easily lead to misinterpretation. In this paper, a two-phase interpretation method applicable to regional-scale active landslide recognition utilizing InSAR results is presented. The first phase utilizes statistical threshold and clustering analysis to detect unstable regions mapped by InSAR. The second phase introduces landslide susceptibility combined with empirical rainfall threshold, which are considered as causative factors for active landslides triggered by rainfall, to screen unstable regions indicative of active landslides. A case study validated by field survey indicates that the proposed interpretation method, when compared to a baseline model reported in the literature, can achieve better interpretation accuracy and miss rate. [ABSTRACT FROM AUTHOR]

Congenital hemangiomas are rare benign vascular tumors but can lead to serious adverse pregnancy outcomes. Its prenatal diagnosis is a challenge. We explored the clinical applications of prenatal ultrasound for evaluating fetal cutaneous hemangioma and associated complications. A retrospective observational study was conducted comprising a population of pregnant women with fetal cutaneous hemangioma, the latter diagnosed by prenatal ultrasound, between January 2016 and December 2020. The clinical characteristics, sonographic images, complications, and pregnancy outcomes were documented and analyzed. We identified 20 cases of fetal cutaneous hemangioma diagnosed by prenatal ultrasound and confirmed by postpartum examinations. Most hemangiomas were in the head and neck (55%), with either solid isoechoicity (25%) or solid mildly hyperechoic (25%), and well-circumscribed (80%) mass. Eight (40%) fetuses experienced complications, which often occurred in fetuses with large hemangiomas (67% with maximum diameter ≥5 cm; 100% with a volume ≥40 cm3). The most common complications were cardiac-related (88%), including elevated cardiothoracic area ratio, atrioventricular valve regurgitation, and fetal hydrops. A large hemangioma was usually associated with advanced gestational age and a fast hemangioma growth rate. In five (25%) cases, the pregnancy was terminated; these involved hemangioma of the head or neck. One newborn developed Kasabach–Merritt phenomenon, pulmonary hemorrhage and respiratory distress, and died 3 days after birth. Among the 14 (70%) fetuses that survived birth, all hemangiomas disappeared or regressed after treatments with propranolol, interventional surgery, or observed routinely. Prenatal ultrasound examination can accurately diagnose fetal cutaneous hemangioma and related complications to facilitate appropriate management during the pregnancy. Prenatal diagnosis of cutaneous hemangiomas is a clinical challenge. Prenatal ultrasound examination could be a method to accurately diagnose and monitor these hemangiomas. [ABSTRACT FROM AUTHOR]