Colletti Vittorio, Mandalà Marco, Carner Marco, Barillari Marco, Cerini Roberto, Pozzi Mucelli Roberto, Colletti Liliana
ENT Department, University of Verona, Verona, Italy. vittoriocolletti @ yahoo.com
Audiol Neurootol. 2010;15(6):353-63. doi: 10.1159/000292929. Epub 2010 Mar 9.
To verify whether injection of substances into the endolymphatic sac (ES) diffuses into the endolymphatic compartments of the human inner ear and in particular to the endolymphatic space of the scala media (ESp-SM), as demonstrated in animals, an exploratory investigation with magnetic resonance imaging (MRI) and intraoperative electrocochleographic recordings (ECoG) was conducted in patients with Ménière's disease (MD) treated with ES decompression. A mixture of dexamethasone and gadolinium (GD) in solution was injected into the ES of 4 patients. The results of the ES injection procedure were compared with administration of the same solution intratympanically (IT, 1 patient) and via a platinotomy in 2 patients. The study was conducted retrospectively at a tertiary referral center. Main outcomes measures were pre- and postintervention complete audiological and neuro-otological evaluation; intraoperative ECoG investigation with evaluation of the morphology of acoustically elicited compound action potentials (CAPs) and 1.5 T MRI evaluations at different follow-up times. Distribution of GD from the ES injection procedure was observed first in the ES, after 24 h in the vestibule and semicircular canals, and after 24-48 h in the ESp-SM in all patients. High signal was detected within the inner ear for 1 week or more (mean: 10 days; range: 7-16 days). Changes in morphology and latency of CAPs were observed within 30 min of the dilatory injection into the ES in all patients. Administration of GD into the vestibule and the IT approach did not distribute the contrast in the ES and GD was observed in the perilymphatic space of the vestibule, cochlea and semicircular canals. No side effects relating to administration of GD into the ES, IT or into the vestibule were observed. To the best of our knowledge this is the first demonstration in humans that drugs injected into the endolymphatic structure of the ES diffuse to the cochlea, presumably into the ESp-SM. The possibility of injecting substances into the endolymphatic space might open up new prospects in the treatment of inner ear disorders. Further studies will be needed to define the limitations of this approach.
为了验证向内淋巴囊（ES）注射物质是否会扩散到人类内耳的内淋巴腔室，特别是中阶内淋巴间隙（ESp-SM），如同在动物实验中所证实的那样，我们对接受ES减压治疗的梅尼埃病（MD）患者进行了一项磁共振成像（MRI）和术中电耳蜗图记录（ECoG）的探索性研究。将地塞米松和钆（GD）的混合溶液注入4例患者的ES。将ES注射程序的结果与1例患者经鼓室内（IT）给药以及2例患者经铂针切开给药的结果进行比较。该研究在一家三级转诊中心进行回顾性研究。主要观察指标为干预前后的完整听力学和神经耳科学评估；术中ECoG检查，评估听觉诱发复合动作电位（CAPs）的形态，以及在不同随访时间进行的1.5T MRI评估。在所有患者中，ES注射程序注入的GD首先出现在ES中，24小时后出现在前庭和半规管中，24 - 48小时后出现在ESp-SM中。内耳内的高信号持续检测到1周或更长时间（平均：10天；范围：7 - 16天）。在所有患者中，向ES内注射稀释液后30分钟内观察到CAPs的形态和潜伏期发生变化。将GD注入前庭以及IT给药方法并未使造影剂在ES中分布，且在前庭、耳蜗和半规管的外淋巴间隙中观察到了GD。未观察到与向ES、IT或前庭注入GD相关的副作用。据我们所知，这是首次在人体中证明注入ES内淋巴结构的药物会扩散至耳蜗，推测是扩散至ESp-SM。向内淋巴间隙注射物质的可能性可能为内耳疾病的治疗开辟新的前景。需要进一步研究来确定这种方法的局限性。
