A computed tomography-based spatial reference for pedicle screw placement in adolescent idiopathic scoliosis.
- 作者列表："Brink RC","Homans JF","de Reuver S","van Stralen M","Schlösser TPC","Viergever MA","Chu WCW","Ng BKW","Castelein RM","Cheng JCY
STUDY DESIGN:Cross-sectional. OBJECTIVES:To determine semiautomatically the 3D position of the pedicle axis in operative adolescent idiopathic scoliosis (AIS) patients relative to the operating table and the lamina, as orientation for pedicle screw placement for better understanding and reference of spine surgeons. Pedicle morphology is well described as the angle between the convex and concave pedicle. However, the pedicle angle as relative to the neutral anterior-posterior axis or to an easy-to-use intravertebral landmark, remained unknown. METHODS:The pedicles of the apex and two adjacent vertebrae cranial and caudal to the apex of 86 right-sided primary thoracic AIS curves were evaluated using semiautomatic 3D software on high-resolution CT scans, in the same prone position as during surgery. Pedicle vectors were obtained and calculated as transverse and sagittal angles, as relative to the neutral axis (corresponding with an axis perpendicular to the operating table) and to an axis perpendicular to the lamina. RESULTS:At the apex, the mean convex and concave transverse pedicle angles were 14.3º (95% confidence interval [95% CI]: 12.0-16.6) and 30.4º (95% CI: 28.1-32.8) to the right. The angles decreased toward the adjacent levels cranial and caudal to the apex (p < 0.001) and linearly increased with a higher Cobb angle (r ≥ 0.472; p < 0.001). The mean transverse pedicle-lamina angles, sagittal pedicle angles and the sagittal pedicle-lamina angles differed along the curve as well (p < 0.001). CONCLUSIONS:Pedicle angulation differs between convex and concave and depends on the position of the vertebra relative to the apex, as well as the curve severity. The transverse and sagittal pedicle angles, as relative to the operating table and laminae, could provide useful reference for better understanding of the distorted 3D morphology, and the angles, as given in this study, could serve as an approximate guideline for the expected direction of the pedicle screw. LEVEL OF EVIDENCE:Level IV.
研究设计: 横断面研究。 目的: 半自动确定青少年特发性脊柱侧凸 (AIS) 手术患者椎弓根轴相对于手术台和椎板的3D位置，作为椎弓根螺钉放置的方向，以便脊柱外科医生更好地理解和参考。椎弓根形态被很好地描述为凸凹椎弓根之间的角度。然而，相对于中性前后轴或易于使用的椎骨内标志的椎弓根角度仍然未知。 方法: 在与手术期间相同的俯卧位下，使用半自动3D软件在高分辨率ct扫描上评估86条右侧原发性胸廓AIS曲线的心尖部和两个相邻椎骨颅和尾端的椎弓根。获得椎弓根矢量，并计算为相对于中性轴 (对应于垂直于手术台的轴) 和垂直于椎板的轴的横向和矢状角度。 结果: 在顶点处，平均凸凹横向椎弓根角为14.3 ° (95% 置信区间 [95% CI]: 12.0-16.6)，右侧为30.4 ° (95% CI: 28.1-32.8)。角度向邻近的头部和顶部的尾部减小 (p <0.001)，并且随着Cobb角的增加而线性增加 (r ≥ 0.472; P <0.001)。平均横向椎弓根-椎板角、矢状椎弓根角和矢状椎弓根-椎板角也沿曲线不同 (p <0.001)。 结论: 椎弓根成角在凸和凹之间不同，并且取决于椎骨相对于顶点的位置，以及曲线的严重程度。相对于手术台和椎板，横向和矢状椎弓根角度可以为更好地理解变形的3D形态提供有用的参考，并且本研究中给出的角度可以作为椎弓根螺钉预期方向的近似指导。 证据级别: IV级。
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.