Kube T, Sutter M, Trittler R, Feltgen N, Hansen L L, Agostini H T
Department of Ophthalmology, University of Freiburg, Killianstrasse 5, 79106 Freiburg, Germany.
Graefes Arch Clin Exp Ophthalmol. 2006 Nov;244(11):1385-90. doi: 10.1007/s00417-006-0326-2. Epub 2006 May 20.
Intravitreal application of triamcinolone acetonide has become increasingly popular for the treatment of various retinal disorders. However, dosage, mode of preparation and application differ worldwide. The aim of this study was to find a safe vehicle that would allow intravitreal injection of an exact amount of triamcinolone acetonide without potentially retinotoxic preservatives.
Solutions of triamcinolone acetonide with a theoretical concentration of 4 mg/0.2 ml were prepared following one sedimentation (A) and two filtration (B, C) methods. In addition, a filtration method using carboxymethylcellulose 2% as a carrier (D) was established. During processing and after injection into an eye model, the crystals were quantified by weight and high-performance liquid chromatography (HPLC), and, hence, the rate of crystal loss during this process was determined.
The initial preparation contained 93-106% of the calculated quantity. Method A, containing the entire vehicle, delivered 45%+/-7.3% of the target quantity to the eye model, whereas the vehicle-free methods B and C delivered 15%+/-6.9% and 11%+/-3.2%, respectively. Using carboxymethylcellulose 2% as a preservative-free vehicle, we found 93%+/-3.7% of the calculated amount in the eye model. The missing crystals were mainly sticking to the walls of the syringes and needles used for transfer.
Common methods for preparing triamcinolone acetonide vary in the amount of drug actually injected intravitreally. Carboxymethylcellulose is an ideal carrier substance for intravitreal application of an exact dose of triamcinolone acetonide without preservatives.
玻璃体内注射曲安奈德已越来越广泛地应用于各种视网膜疾病的治疗。然而，其剂量、配制和应用方式在全球范围内存在差异。本研究的目的是找到一种安全的载体，能够在不使用具有潜在视网膜毒性防腐剂的情况下，实现玻璃体内精确注射一定量的曲安奈德。
按照一种沉降法（A）和两种过滤法（B、C）制备理论浓度为4mg/0.2ml的曲安奈德溶液。此外，还建立了一种以2%羧甲基纤维素为载体的过滤法（D）。在制备过程中以及注射到眼模型后，通过称重和高效液相色谱法（HPLC）对晶体进行定量，从而确定该过程中晶体的损失率。
初始制剂含有计算量的93%-106%。含有全部载体的方法A向眼模型输送了目标量的45%±7.3%，而无载体的方法B和C分别输送了15%±6.9%和11%±3.2%。使用2%羧甲基纤维素作为无防腐剂载体时，我们在眼模型中发现了计算量的93%±3.7%。缺失的晶体主要附着在用于转移的注射器和针头壁上。
曲安奈德的常用制备方法在实际玻璃体内注射的药物量方面存在差异。羧甲基纤维素是在不使用防腐剂的情况下玻璃体内精确注射一定剂量曲安奈德的理想载体物质。
