ABSTRACT
Objective:To explore the feasibility of ultrasound screening and diagnosis of fetal cleft palate in early pregnancy, analyze and summarize the imaging technology and image characteristics of two-dimensional and three-dimensional ultrasound in normal fetus and cleft palate fetus.Methods:A total of 10 519 pregnant women participated in the early pregnancy were included from January 2016 to June 2020 in Shenzhen Hospital, University of Chinese Academy of Sciences. The palatal line on the standard section of fetal nuchal translucency (NT) measurement was used as a screening marker for routine observation. For fetuses with abnormal palatine line, posterior nasal triangle of coronal plane and axial plane of maxillary alveolar arch of two-dimensional ultrasound were added as the diagnostic sections, and three-dimensional volume data of fetal face were collected, and three dimensional multimodal imaging technology was used to analyze the volume data off-line to determine or exclude fetal severe cleft palate. All fetuses were followed up during the second trimester for deformity scanning and post natal (or induced labor) assessment.Results:Of the 10 519 fetuses, the standard NT plane was obtained and the palatal line was observed in 10 204 cases(97.01%), with normal palatal line in 10 169 cases.In 35 suspected cases, 13 cases were confirmed cleft lip and palate by two and three dimensions ultrasound, and were confirmed by induced labor. There were 7 cases in unilateral side, 3 cases in bilateral, 2 cases in median cleft lip and palate, 1 cases in irregular cleft lip and palate, and no false positive results were reported. Twenty-two suspicious cases were excluded by increasing the two-dimensional sectional and three-dimensional volumetric off-line analysis, and screening after the second trimester and after birth. There was 1 case of missed diagnosis of simple cleft palate.Conclusions:Palatal line is a good screening marker for fetal cleft palate in early pregnancy. For fetuses with abnormal palatine line, the adding of posterior nasal triangle and the axial plane of maxillary alveolar arch, and combining three-dimensional volume data for off-line analysis can determine or exclude severe cleft palate. This study is of great significance for early screening and diagnosis of severe fetal cleft palate, prenatal genetic counseling and prevention birth defect.
ABSTRACT
Objective To investigate the establishment of focal cerebral ischemia model in rabbits with the improved suture method.Methods A total of 45 healthy and clean adult New Zealand rabbits were divided into either a sham operation group (n =5) or a model group (n =40) using random number table method before modeling,and the sex was not limited.The self-made head ends of 2-0 fishing lines dipped in paraffin were used as the sutures.The external carotid artery was cut and inserted into a intracranial artery through the internal carotid artery and blocked the origin of middle cerebral artery.The neurological function score was performed after 6 h.The neurological deficit scores ≥2 was successful modeling.The rabbits were killed by anesthesia.The brain slices were stained with 2％ 2,3,5-triphenyl tetrazolium chloride solution.The infarct foci were observed.The diameters of suture head and the depth of suture insertion were compared in the model rabbits with successful modeling,failure,and death in the model group.Results There were 40 rabbits in the model group,six of them died,including 4 died of subarachnoid hemorrhage within 4 h after operation,and 2 died from anesthetic accident.The mortality rate was 15.0％.Seven rabbits failed,mainly because of cerebral vasospasm and the insertion depth of suture was insufficient.Twenty-seven had successful modeling,and the success rate was 67.5％.All the rabbits in the sham operation group survived.The diameter of the suture head and insertion depth in the successful modeling rabbits were compared with the death and failure outcome in rabbits.The difference was statistically significant (diameter:0.52 ± 0.14 mm vs.0.45 ±0.40 mm and 0.58 ±0.17 mm;depth:5.49 ±0.17 cm vs.6.04 ± 0.11 cm and 4.26 ±0.30 cm;all P ＜ 0.05).Conclusions The improved suture method can successfully prepare the focal cerebral ischemia model of middle cerebral artery in rabbits.The method is simple.Its repeatability and practicability are better.