METHODS: Hanusch Hospital, Vienna, Austria.
METHODS: Laboratory Investigation.
UNASSIGNED: 30 G (gauge) thin wall and 27 G standard needles were used for a 2 mm tangential scleral tunnel in combination with different PVDF (polyvinylidene fluoride) and PMMA (polymethylmethacrylate haptics). Flanges were created by heating 1 mm of the haptic end, non-forceps assisted in PVDF and forceps assisted in PMMA haptics. The dislocation force was measured in non-preserved cadaver sclera using a tensiometer device.
RESULTS: PVDF flanges achieved were of a mushroom-like shape and PMMA flanges were of a conic shape. For 30 G needle tunnels the dislocation forces for PVDF and PMMA haptic flanges were 1.58 ± 0.68 N (n = 10) and 0.70 ± 0.14 N (n = 9) (p = 0.003) respectively. For 27 G needle tunnels the dislocation forces for PVDF and PMMA haptic flanges were 0.31 ± 0.35 N (n = 3) and 0.0 N (n = 4), respectively. The flange size correlated with the occurring dislocation force in experiments with 30 G needle tunnels (r = 0.92), when flanges were bigger than 384 micrometres.
CONCLUSIONS: The highest dislocation forces were found for PVDF haptic flanges and their characteristic mushroom-like shape for 30 G thin wall needle scleral tunnels. Forceps assisted flange creation in PMMA haptics did not compensate the disadvantage of PMMA haptics with their characteristic conic shape flange.
方法:Hanusch医院,维也纳,奥地利。
方法:实验室调查。
■将30G(规格)薄壁和27G标准针与不同的PVDF(聚偏二氟乙烯)和PMMA(聚甲基丙烯酸甲酯触觉)组合用于2mm切向巩膜隧道。通过加热1毫米的触觉端创建法兰,非镊子辅助PVDF和镊子辅助PMMA触觉。使用张力计装置在未保存的尸体巩膜中测量脱位力。
结果:获得的PVDF法兰为蘑菇状,PMMA法兰为圆锥形。对于30G针隧道,PVDF和PMMA触觉法兰的错位力分别为1.58±0.68N(n=10)和0.70±0.14N(n=9)(p=0.003)。对于27G针隧道,PVDF和PMMA触觉法兰的错位力为0.31±0.35N(n=3)和0.0N(n=4),分别。在30G针隧道的实验中,法兰尺寸与发生的位错力相关(r=0.92),当法兰大于384微米时。
结论:对于30G薄壁针巩膜隧道,PVDF触觉法兰及其特征性蘑菇状形状发现了最高的错位力。镊子辅助PMMA触觉中的凸缘创建并不能弥补PMMA触觉的缺点,其特征为圆锥形凸缘。