Naganawa S, Ito T, Iwayama E, Fukatsu H, Ishigaki T, Nakashima T, Ichinose N
Department of Radiology, Nagoya University School of Medicine, Japan.
Radiology. 1999 Dec;213(3):819-23. doi: 10.1148/radiology.213.3.r99dc05819.
To evaluate the cochlear modiolus with thin-section magnetic resonance (MR) imaging in healthy subjects and patients with a large endolymphatic duct and sac, and to assess whether the cochlea is normal or abnormal in patients with a large endolymphatic duct and sac.
MR images were obtained in 10 ears in five volunteers (group 1), 40 ears in 20 patients with bilateral sensory hearing loss (group 2), three ears in two patients with Mondini malformation (group 3), and 12 ears in seven patients with a large endolymphatic duct and sac (group 4).
In groups 1 and 2, all modiolar areas were larger than 4.0 mm2. In group 3, each modiolus was smaller than 2.0 mm2. In group 4, modiolar areas were smaller than 2.0 mm2 in eight ears and were larger than 4.0 mm2 in four ears.
Findings in this study confirm that a large endolymphatic duct and sac is frequently associated with modiolar deficiency, but the modiolar area is normal in some cases. This result does not support the recently proposed hypothesis that hearing loss with a large endolymphatic duct and sac is caused by the transmission of subarachnoid pressure forces into the labyrinth through a deficient modiolus.
采用薄层磁共振成像（MR）评估健康受试者以及内淋巴管和内淋巴囊扩大患者的蜗轴，并评估内淋巴管和内淋巴囊扩大患者的耳蜗是否正常。
对5名志愿者的10只耳（第1组）、20名双侧感音神经性听力损失患者的40只耳（第2组）、2名Mondini畸形患者的3只耳（第3组）以及7名内淋巴管和内淋巴囊扩大患者的12只耳（第4组）进行MR成像。
在第1组和第2组中，所有蜗轴面积均大于4.0平方毫米。在第3组中，每个蜗轴小于2.0平方毫米。在第4组中，8只耳的蜗轴面积小于2.0平方毫米，4只耳的蜗轴面积大于4.0平方毫米。
本研究结果证实，内淋巴管和内淋巴囊扩大常与蜗轴缺损相关，但在某些情况下蜗轴面积正常。这一结果不支持最近提出的假说，即内淋巴管和内淋巴囊扩大导致的听力损失是由蛛网膜下腔压力通过缺损的蜗轴传递至迷路所致。
