Three-dimensional assessment of facial asymmetry using dense correspondence, symmetry, and midline analysis.
- 作者列表："Lum V","Goonewardene MS","Mian A","Eastwood P
INTRODUCTION:It is considered normal for facial structures to exhibit mild asymmetry between left and right sides. An automated, landmark-independent method was developed to accurately assess and quantify facial asymmetry in 3 planes of space and describe a midline deviation of each subject and ultimately establish thresholds of significance. METHODS:The subjects were 279 healthy young Western Australian white adults (134 females and 145 males) with a mean age 22.17 years ± 0.63, (minimum 20.58 years-maximum 24.42 years) without craniofacial anomalies. They were randomly selected from participants in the Raine Study-Generation 2. Surface facial images were obtained using a 3dMDface scanning system (3dMD Inc, Atlanta, Ga). Images were standardized using the dense correspondence technique. An automated landmark detection method was applied, and measurements performed on color deviation maps to quantitatively assess facial asymmetry. RESULTS:Based on asymmetrical projections over the total facial surface area, the proportion of female and males with moderate asymmetry (2-5 mm) was 52.3% and 58.4%, respectively, and with severe asymmetry (>5 mm) was 7.1% and 7.7%, respectively. Most asymmetry occurred in the coronal plane (x-axis), followed by the transverse plane (z-axis) and the least asymmetry in the sagittal plane (y-axis). Males were statistically more asymmetrical (P <0.05) in the coronal and transverse planes (males: coronal 36.5%, transverse 15.2%; females: coronal 31.8%, transverse 12.3%). The midline was deviated to the right in all females and in all but 1 male subject. CONCLUSIONS:This study presents an automated, rapid and accurate method of assessing 3-dimensional facial asymmetry (using symmetry and midline analyses). Analyses revealed that >50% of the faces of young adults are >2 mm asymmetrical, based on total facial surface area.
简介: 面部结构表现出左右两侧轻度不对称被认为是正常的。开发了一种自动的、与界标无关的方法，以准确评估和量化3个空间平面中的面部不对称，并描述每个受试者的中线偏差，最终建立显著性阈值。 方法: 研究对象为279名健康年轻的西澳大利亚白人成年人 (134名女性和145名男性)，平均年龄22.17岁 ± 0.63岁 (最小20.58岁-最大24.42岁)，无颅面异常。他们是从第2代Raine研究的参与者中随机选择的。使用3dmdface扫描系统 (3dMD Inc，亚特兰大，Ga) 获得表面面部图像。使用密集对应技术对图像进行标准化。应用自动界标检测方法，并在颜色偏差图上进行测量以定量评估面部不对称性。 结果: 基于面部总表面积的不对称投影，女性和男性中度不对称 (2-5毫米) 的比例分别为52.3% 和58.4%，重度不对称 (> 5毫米) 的比例分别为7.1% 和7.7%。大多数不对称发生在冠状平面 (x轴)，其次是横向平面 (z轴) 和矢状平面 (y轴) 中的最小不对称。男性在冠状面和横向面统计上更加不对称 (P <0.05) (男性: 冠状面36.5%，横向15.2%; 女性: 冠状面31.8%，横向12.3%)。在所有女性和除1名男性受试者之外的所有受试者中，中线偏右。 结论: 本研究提出了一种自动，快速和准确的评估三维面部不对称的方法 (使用对称性和中线分析)。分析显示，基于总面部表面积，> 50% 的年轻人面部> 2毫米不对称。
METHODS:OBJECTIVES:The aim was to evaluate the image quality and sensitivity to artifacts of compressed sensing (CS) acceleration technique, applied to 3D or breath-hold sequences in different clinical applications from brain to knee. METHODS:CS with an acceleration from 30 to 60% and conventional MRI sequences were performed in 10 different applications in 107 patients, leading to 120 comparisons. Readers were blinded to the technique for quantitative (contrast-to-noise ratio or functional measurements for cardiac cine) and qualitative (image quality, artifacts, diagnostic findings, and preference) image analyses. RESULTS:No statistically significant difference in image quality or artifacts was found for each sequence except for the cardiac cine CS for one of both readers and for the wrist 3D proton density (PD)-weighted CS sequence which showed less motion artifacts due to the reduced acquisition time. The contrast-to-noise ratio was lower for the elbow CS sequence but not statistically different in all other applications. Diagnostic findings were similar between conventional and CS sequence for all the comparisons except for four cases where motion artifacts corrupted either the conventional or the CS sequence. CONCLUSIONS:The evaluated CS sequences are ready to be used in clinical daily practice except for the elbow application which requires a lower acceleration. The CS factor should be tuned for each organ and sequence to obtain good image quality. It leads to 30% to 60% acceleration in the applications evaluated in this study which has a significant impact on clinical workflow. KEY POINTS:• Clinical implementation of compressed sensing (CS) reduced scan times of at least 30% with only minor penalty in image quality and no change in diagnostic findings. • The CS acceleration factor has to be tuned separately for each organ and sequence to guarantee similar image quality than conventional acquisition. • At least 30% and up to 60% acceleration is feasible in specific sequences in clinical routine.
METHODS:BACKGROUND:The main surgical techniques for spontaneous basal ganglia hemorrhage include stereotactic aspiration, endoscopic aspiration, and craniotomy. However, credible evidence is still needed to validate the effect of these techniques. OBJECTIVE:To explore the long-term outcomes of the three surgical techniques in the treatment of spontaneous basal ganglia hemorrhage. METHODS:Five hundred and sixteen patients with spontaneous basal ganglia hemorrhage who received stereotactic aspiration, endoscopic aspiration, or craniotomy were reviewed retrospectively. Six-month mortality and the modified Rankin Scale score were the primary and secondary outcomes, respectively. A multivariate logistic regression model was used to assess the effects of different surgical techniques on patient outcomes. RESULTS:For the entire cohort, the 6-month mortality in the endoscopic aspiration group was significantly lower than that in the stereotactic aspiration group (odds ratio (OR) 4.280, 95% CI 2.186 to 8.380); the 6-month mortality in the endoscopic aspiration group was lower than that in the craniotomy group, but the difference was not significant (OR=1.930, 95% CI 0.835 to 4.465). A further subgroup analysis was stratified by hematoma volume. The mortality in the endoscopic aspiration group was significantly lower than in the stereotactic aspiration group in the medium (≥40-<80 mL) (OR=2.438, 95% CI 1.101 to 5.402) and large hematoma subgroup (≥80 mL) (OR=66.532, 95% CI 6.345 to 697.675). Compared with the endoscopic aspiration group, a trend towards increased mortality was observed in the large hematoma subgroup of the craniotomy group (OR=8.721, 95% CI 0.933 to 81.551). CONCLUSION:Endoscopic aspiration can decrease the 6-month mortality of spontaneous basal ganglia hemorrhage, especially in patients with a hematoma volume ≥40 mL.
METHODS:OBJECTIVE:The primary purpose of this study was to evaluate the effectiveness of a three-dimensional (3D) software tool (smart planes) for displaying fetal brain planes, and the secondary purpose was to evaluate its accuracy in performing automatic measurements. MATERIAL AND METHODS:This prospective study included singleton fetuses with a gestational age (GA) greater than 18 weeks. Transabdominal two-dimensional ultrasound (2DUS) and 3D smart planes images were respectively used to obtain the basic planes of the fetal brain, with five parameters measured. The images, by either two-dimensional (2D) manual or 3D automatic operation, were reviewed by two experienced sonographers. The agreements between two measurements were analyzed. RESULTS:A total of 226 cases were included. The rates of successful detection by automatic display were as high as 80%. There was substantial agreement between the measurements of the biparietal diameter, head circumference and transcerebellar diameter, but poor agreement between the measurements of cisterna magna and lateral ventricle width. CONCLUSIONS:Smart Planes might be valuable for the rapid evaluation of fetal brain, because it simplifies the evaluation process. However, the technology requires improvement. In addition, this technology cannot replace the conventional manual US scans; it can only be used as an additional approach.