Introduction: Patients with hydrocephalus, which is the most pediatric neurological disorder, undergo Cerebrospinal fluid (CSF) diversion through third ventriculostomy or ventriculo-peritoneal shunt. Up to date, the o...Introduction: Patients with hydrocephalus, which is the most pediatric neurological disorder, undergo Cerebrospinal fluid (CSF) diversion through third ventriculostomy or ventriculo-peritoneal shunt. Up to date, the optimal hydrocephalus treatment modality is not clear. Aim: We compared the outcome of endoscopic third ventriculostomy (ETV) versus ventriculo-peritoneal shunt (VP shunt) as a second surgical intervention in management of Infant hydrocephalus concerning success rate and complications. Patients and Methods: We conducted an observational study of 52 children with hydrocephalus (congenital or acquired) in whom CSF diversion was performed using either ETV or VP shunt in randomized control trial. Results: During the period examined, 52 children, 26 underwent ETV and 26 underwent VP shunt. The mean age was 11.0 ± 4.3 months in ETV and 11.3 ± 4.7 months in VP shunt. Postoperative infection in the ETV group was lower than in the VP shunt group (23.1% vs. 53.8% P = 0.045). Regarding operating time, In ETV group operation duration was 46.9 min and 64.3 min in the V-P shunt group (P = 0.13). There was no statistically significant difference between the two study groups regarding the rate of obstruction, change in occipital frontal circumference (OFC) or the need of revision surgery. One year survival for VP shunt group vs. ETV group was 46.2% vs. 65.4% respectively. Conclusion: ETV associated with lower rates of postoperative infection and shorter operation time with no significant difference in rates of obstruction, change in OFC and revision surgery in comparison to VP shunt.展开更多
Vortex double layers (VDLs) and vortex projectiles (VPs) are the essential coherent structures which emerge in the shock excited (s/f/s) planar parallel "curtain" simulations of a 2D shock tube with PPM. The...Vortex double layers (VDLs) and vortex projectiles (VPs) are the essential coherent structures which emerge in the shock excited (s/f/s) planar parallel "curtain" simulations of a 2D shock tube with PPM. These opposite signed layers, formed by shock induced baroclinic deposition of vorticity, "ind" and are strongly affected by secondary reflected shocks and vortex interactions. In our visiometric mode of working, we quantify several of these processes and introduce time epochs to discuss the emerging phenomena and normalizations to scale (collapse) the data at M =1.5 and 2.0. This versatile configuration, easily obtained in the laboratory, allows us to study the formation, evolution and reacceleration of VPs and stratified turbulence and mixing.展开更多
文摘Introduction: Patients with hydrocephalus, which is the most pediatric neurological disorder, undergo Cerebrospinal fluid (CSF) diversion through third ventriculostomy or ventriculo-peritoneal shunt. Up to date, the optimal hydrocephalus treatment modality is not clear. Aim: We compared the outcome of endoscopic third ventriculostomy (ETV) versus ventriculo-peritoneal shunt (VP shunt) as a second surgical intervention in management of Infant hydrocephalus concerning success rate and complications. Patients and Methods: We conducted an observational study of 52 children with hydrocephalus (congenital or acquired) in whom CSF diversion was performed using either ETV or VP shunt in randomized control trial. Results: During the period examined, 52 children, 26 underwent ETV and 26 underwent VP shunt. The mean age was 11.0 ± 4.3 months in ETV and 11.3 ± 4.7 months in VP shunt. Postoperative infection in the ETV group was lower than in the VP shunt group (23.1% vs. 53.8% P = 0.045). Regarding operating time, In ETV group operation duration was 46.9 min and 64.3 min in the V-P shunt group (P = 0.13). There was no statistically significant difference between the two study groups regarding the rate of obstruction, change in occipital frontal circumference (OFC) or the need of revision surgery. One year survival for VP shunt group vs. ETV group was 46.2% vs. 65.4% respectively. Conclusion: ETV associated with lower rates of postoperative infection and shorter operation time with no significant difference in rates of obstruction, change in OFC and revision surgery in comparison to VP shunt.
文摘Vortex double layers (VDLs) and vortex projectiles (VPs) are the essential coherent structures which emerge in the shock excited (s/f/s) planar parallel "curtain" simulations of a 2D shock tube with PPM. These opposite signed layers, formed by shock induced baroclinic deposition of vorticity, "ind" and are strongly affected by secondary reflected shocks and vortex interactions. In our visiometric mode of working, we quantify several of these processes and introduce time epochs to discuss the emerging phenomena and normalizations to scale (collapse) the data at M =1.5 and 2.0. This versatile configuration, easily obtained in the laboratory, allows us to study the formation, evolution and reacceleration of VPs and stratified turbulence and mixing.
