Massey Becky L, Wen Xuejun, Rohr L Ralph, Tresco Patrick A, Dahlstrom Lisa, Park Albert H
Division of Otolaryngology--Head and Neck Surgery, University of Utah, Salt Lake City 84132, USA.
Otolaryngol Head Neck Surg. 2004 Dec;131(6):921-5. doi: 10.1016/j.otohns.2004.07.003.
Determine the resorption rate and biocompatibility characteristics of 2 polyester ventilation tubes, and to determine whether soap and water exposure accelerates polyester tube degradation.
50/50 poly (D, L-lactide-co-glycolide; PLGA-50) and poly (L-lactide; PLA) polymers were placed into the tympanic membranes of Hartley pigmented guinea pigs. Integrity of the tubes was determined by weekly otoscopic examination. Biocompatibility was assessed by comparing auditory brainstem response (ABR) thresholds and by examining tympanic membrane changes following tube resorption. Shah minigrommet ventilation tubes were used as controls. In the second portion of this study, implanted PLGA-50 and PLA tubes were exposed weekly to a mixture of soap and water (1:5) until complete resorption was observed. Biocompatibility was assessed by periodic ABR testing and tympanic membrane examination.
The PLA tubes remained in the tympanic membrane for a longer period (63.2 +/- 19.3 days) than the PLGA-50 (18.8 +/- 8.1 days). The tympanic membrane and resorbable tube interface demonstrated equivalent findings for auditory thresholds and tissue histopathology at the implant site compared to nonresorbable controls. The resorption behavior was not altered by exposure to soap and water. Tympanic membranes of all animals following tube degradation and soap water exposure were intact with minimal scarring and no signs of persistent foreign body response. The histological analysis showed that implantation of resorbable tubes was not accompanied by secondary infection with otorrhea through the tube, did not result in a permanent perforation or dislocation of the tube into the middle ear cavity, and was not followed by excess tympanosclerosis or localized or diffuse membrane atrophy.
Resorbable polyester pressure equalization tubes demonstrate predictable resorption behavior and similar biocompatibility characteristics when compared with nonresorbable Shah minigrommet ventilation tubes. Exposure to soap water does not accelerate polyester tube degradation nor change the host tissue response during the indwelling period or after complete resorption. The data suggests that resorbable ventilation tubes are substantially equivalent to other FDA-approved tympanostomy devices with regard to safety and biocompatibility in the guinea pig model examined and may provide improved clinical performance by combining this approach with sustained release technology.
B-2.
确定2种聚酯通气导管的吸收速率和生物相容性特征，并确定肥皂和水暴露是否会加速聚酯导管的降解。
将50/50聚（D，L-丙交酯-共-乙交酯；PLGA-50）和聚（L-丙交酯；PLA）聚合物置于哈特利有色豚鼠的鼓膜中。通过每周一次的耳镜检查确定导管的完整性。通过比较听觉脑干反应（ABR）阈值并检查导管吸收后鼓膜的变化来评估生物相容性。使用沙阿微型通气管作为对照。在本研究的第二部分中，将植入的PLGA-50和PLA导管每周暴露于肥皂和水的混合物（1:5）中，直至观察到完全吸收。通过定期的ABR测试和鼓膜检查评估生物相容性。
PLA导管在鼓膜中保留的时间（63.2±19.3天）比PLGA-50导管（18.8±8.1天）更长。与不可吸收的对照相比，鼓膜和可吸收导管界面在植入部位的听觉阈值和组织组织病理学方面表现出相同的结果。暴露于肥皂和水不会改变吸收行为。所有动物的鼓膜在导管降解和肥皂水暴露后均保持完整，瘢痕形成最小，且无持续性异物反应的迹象。组织学分析表明，植入可吸收导管不会伴有通过导管的耳漏继发感染，不会导致导管永久性穿孔或移位至中耳腔，也不会伴有过多的鼓室硬化或局部或弥漫性鼓膜萎缩。
与不可吸收的沙阿微型通气管相比，可吸收聚酯压力平衡导管表现出可预测的吸收行为和相似的生物相容性特征。暴露于肥皂水中不会加速聚酯导管的降解，也不会在留置期间或完全吸收后改变宿主组织反应。数据表明，在所研究的豚鼠模型中，就安全性和生物相容性而言，可吸收通气导管与其他FDA批准的鼓膜造口术装置基本等效，并且通过将这种方法与缓释技术相结合可能会提供更好的临床性能。
B-2。
