Evaluation of prednisolone and prednisolone sodium succinate concentrations in human plasma and inner ear perilymph during cochlear implantation 24 h after intratympanic injection

Abstract

Background

The use of intratympanic (IT) steroids has drastically increased over the past 10–15 years to manage many otological pathologies.

Objectives

This study aimed to compare the concentrations of prednisolone and prednisolone sodium succinate (SS) in the plasma and inner ear perilymph of participants who underwent cochlear implantation 24 h after IT injection.

Materials and methods

It was a prospective comparative randomized study. Twenty participants received an IT injection of prednisolone SS ∼24 h before the cochlear implantation. The other five participants received an IT saline injection and represented the control group. Perilymph and blood were sampled during the cochlear implantation surgery.

Results

Both prednisolone and prednisolone SS were still present in perilymph ∼24 h after the IT administration. Only prednisolone was present in the blood plasma of seven participants (35%).

Conclusion

IT injection of prednisolone SS resulted in high perilymph concentrations of prednisolone and prednisolone SS, which could stay in the perilymph for at least 24 h. Using a mini-endoscope during the IT injection may effectively detect barriers infront of the round window membrane, increasing the drug concentration in the inner ear.

Significance

IT injection is an effective method for delivering prednisolone to the inner ear.

Chinese Abstract

背景：在过去 10-15 年中, 鼓室内 (IT) 类固醇在管理许多耳科疾病上的使用急剧增加。

目的：本研究旨在比较IT 注射后24 小时接受耳蜗植入的参与者的血浆和内耳外淋巴中的泼尼松龙和泼尼松龙琥珀酸钠 (SS)的浓度。

材料和方法：这是一项前瞻性比较随机研究。二十名参加者在人工耳蜗植入前 24 小时接受了泼尼松龙 SS 的 IT 注射。其他五名参与者作为对照组接受了 IT 盐水注射。外淋巴和血液是在人工耳蜗植入手术期间取样。

结果：IT 后 24 小时, 泼尼松龙和泼尼松龙 SS 仍存在于外淋巴中。七名参与者 (35%) 的血浆中仅存在泼尼松龙。

结论：IT 注射泼尼松龙 SS 导致泼尼松龙和泼尼松龙 SS在外淋巴液中浓度高, 它们可以在外淋巴中停留至少 24 小时。在 IT 注射期间使用微型内窥镜可以有效地检测圆窗膜前方的障碍物, 增加内耳中的药物浓度。

意义：IT注射是将泼尼松龙输至内耳的有效方法。

Keywords:

• Cochlear implant
• intratympanic injection
• perilymph
• prednisolone
• round window membrane

Author contributions

E.C. designed the work; C.F. acquired and analyzed data; R.F. acquired and analyzed data; G.P. acquired and analyzed data; C.G. drafted, revised, and approved the manuscript; H.H.E. drafted, revised, approved the manuscript; M.B. agreed to be accountable for all aspects of the work and performed the included surgeries.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

The data presented in this study are available on request from the corresponding author.