Driben J S, Bolger W E, Robles H A, Cable B, Zinreich S J
Department of Otolaryngology, National Naval Medical Center, Bethesda, Maryland, USA.
Am J Rhinol. 1998 Mar-Apr;12(2):105-11. doi: 10.2500/105065898781390325.
Optic nerve injury is a devastating potential complication of endoscopic sinus surgery. Anatomic variations of the posterior ethmoid sinus are certainly contributing factors. In the most well described posterior ethmoid anatomical variant, the sphenoethmoid or Onodi cell, the optic nerve is placed at risk during sinus surgery. Improving preoperative and intraoperative identification of the sphenoethmoid (Onodi) cell could decrease the risk of optic nerve injury. The purpose of this investigation was to assess the reliability of computerized tomography (CT) in detecting the sphenoethmoid (Onodi) cell, and further our understanding of this clinically relevant anatomic variant. A total of 41 sinonasal complexes from 21 human adult cadaveric heads were studied with a standard coronal and axial plane CT, and subsequent endoscopic dissection. The prevalence of the sphenoethmoid (Onodi) cell was determined by CT and endoscopic dissection, as were other anatomic characteristics of the posterior ethmoid anatomy. In our study, CT identified a sphenoethmoid (Onodi) cell in 3/41 (7%) of the sphenoethmoid complexes. However, anatomic dissection identified a sphenoethmoid (Onodi) cell in 16/41 (39%) complexes. Coronal orientation of the anterior sphenoid wall was never associated with a sphenoethmoid (Onodi) cell. Conversely, oblique or horizontal orientations were present in all cases of sphenoethmoid (Onodi) cells. Current CT scanning protocols for the paranasal sinuses did not reliably detect the Onodi cell. Endoscopic dissection indicates that the sphenoethmoid (Onodi) cell is a more frequent anatomic variant than previously appreciated. Awareness of anterior sphenoid wall orientation may assist surgeons in identifying the Onodi cell, thereby reducing the risk of optic nerve trauma.
视神经损伤是鼻内镜鼻窦手术一种严重的潜在并发症。后筛窦的解剖变异无疑是促成因素。在描述最为详尽的后筛窦解剖变异中，即蝶筛或Onodi气房，视神经在鼻窦手术中会面临风险。提高术前和术中对蝶筛（Onodi）气房的识别能力可降低视神经损伤的风险。本研究的目的是评估计算机断层扫描（CT）检测蝶筛（Onodi）气房的可靠性，并加深我们对这种具有临床相关性的解剖变异的理解。对来自21个成人尸头的41个鼻窦复合体进行了标准冠状面和轴位面CT扫描以及随后的内镜解剖研究。通过CT和内镜解剖确定蝶筛（Onodi）气房的发生率以及后筛窦解剖结构的其他特征。在我们的研究中，CT在41个蝶筛复合体中的3个（7%）中识别出蝶筛（Onodi）气房。然而，解剖发现41个复合体中有16个（39%）存在蝶筛（Onodi）气房。蝶骨前壁的冠状位方向与蝶筛（Onodi）气房从未相关。相反，所有蝶筛（Onodi）气房的病例均存在斜位或水平位。目前用于鼻窦的CT扫描方案不能可靠地检测到Onodi气房。内镜解剖表明，蝶筛（Onodi）气房是一种比之前认识到的更为常见的解剖变异。了解蝶骨前壁的方向可能有助于外科医生识别Onodi气房，从而降低视神经损伤的风险。
