后Tenon囊下注射曲安奈德后玻璃体腔内药物质量浓度的测定

目的探讨后Tenon囊下注射曲安奈德（TA）后玻璃体腔内的药物质量浓度及代谢情况。方法32只健康成年有色家兔,右眼为实验眼,给予后Tenon囊下注射TA20mg（0.1mL）;左眼为对照眼,给予后Tenon囊下注射生理盐水0.1mL,依据注射后不同时间点分为第1、3、7天,2、3、4、6、8周8个亚组,于注药前及注药后各时间点行裂隙灯检查、眼压测量并处死1组家兔,取玻璃体样本,用高效液相色谱法测定药物质量浓度并行药物代谢动力学分析。结果所有家兔未见手术及药物所致的并发症。玻璃体腔内药物质量浓度于第2周达到最高,为（1.91±0.13）μg/mL,以后逐渐下降。结论后Tenon囊下注射TA,在玻璃体腔内可达到并维持一定的药物质量浓度。

Detect of vitreous drug concentration following injection of triamcinolone acetonide via posterior sub-Tenon

Objective Triamcinolone acetonide （TA） is effective for the management of maeular edema by intravitreous injection, but the injection procedure increases the risk of intraocular infection. The aim of this study was to establish the injection approach of TA via posterior sub-Tenon＇ s sac and investigate the drug concentration in vitreous after a posterior sub-Tenon＇ s TA injection. Methods The right eyes of 32 rabbits received a posterior sub-Tenon＇ s injection of 20 mg TA （0. 1 mL） suspension as the experimental eyes,and the fellow eyes received 0. 1 mL normal saline solution as the control eyes. The rabbits were divided into eight subgroups according to the time after drug injection. The intraocular pressure （IOP） and slit-lamp examination were recorded before and after drug injection to evaluate the safety of posterior sub-Tenon＇ s TA injection. The rabbits were killed at 1 day, 3,7 days ,2,3,4,6,8 weeks following injection of TA respectively and the vitreous specimens were collected immediately. TA concentration in vitreous were detected by high performance liquid chromatography （HPLC） and the pharmacokinetics analysis of drug was performed. 1 μg/mL prednisolone-methanol solution was as reference solution. Results The regression equation of TA /prednisolone peak area（Y） and TA/prednisolone concentration （X） was Y = 0. 432 9X ＋ 0. 539 7, presenting a good linear correlation between them （R2 = 0. 995 1 ,P 〈 0. 05 ）. A higher TA level was seen from 7 through 14 days following the TA injeetion with the maximal concentration 1.91± 0. 13 μg/mL at 14 days and after that showed a declining trend till 56 days. The half life period of TA in vitreous was calculated to be 8.5 days. No any ocular complication was found throughout the studing duration. No significant alteration was found in IOP between before and after injection of TA or TA group and normal saline solution group（ P 〉 0. 05）. Conclusion The injection of TA via posterior sub-Tenon＇ s capsule is a safe procedu