Bendersky Damián C, Landriel Federico A, Ajler Pablo M, Hem Santiago M, Carrizo Antonio G
Department of Neurosurgery, Hospital Italiano de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina.
Surg Neurol Int. 2011;2:171. doi: 10.4103/2152-7806.90034. Epub 2011 Nov 19.
Intrasphenoidal encephaloceles are extremely rare findings. Sternberg's canal is a lateral craniopharyngeal canal resulting from incomplete fusion of the greater wings of the sphenoid bone with the basisphenoid. It acts as a weak spot of the skull base, which may lead to develop a temporal lobe encephalocele protruding into the lateral recess of the sphenoid sinus (SS).
We present two cases of intrasphenoidal encephalocele due to persistence of the lateral craniopharyngeal canal. The first case presented with cerebrospinal fluid (CSF) rhinorrhea and the second one was referred to the neurosurgical department with CSF rhinorrhea and meningitis. Radiological investigations consisted of computed tomography (CT) scan, CT cisternography and magnetic resonance images in both cases. These imaging studies identified a herniated temporal lobe through a bony defect which communicates the middle cranial fossa with the lateral recess of the SS. Both patients underwent a transcranial repair of the encephalocele because of the previous failure of the endoscopic surgery. There was no complication related to the surgical procedure and no recurrence of CSF leakage occurred 2 and 3 years after surgery, respectively.
Encephalocele within the lateral recess of the SS is a rare entity which must be suspected in patients who present with spontaneous CSF rhinorrhea. Congenital intrasphenoidal encephaloceles, which are located medial to the foramen rotundum, seem to be due to persistence of the Sternberg's canal. Transcranial approach is a good option when a transnasal approach had failed previously.
蝶窦内脑膨出是极为罕见的发现。施特恩贝格管是一种外侧颅咽管，由蝶骨大翼与蝶骨体未完全融合形成。它是颅底的一个薄弱部位，可能导致颞叶脑膨出突入蝶窦外侧隐窝。
我们报告两例因外侧颅咽管持续存在导致的蝶窦内脑膨出。第一例表现为脑脊液鼻漏，第二例因脑脊液鼻漏和脑膜炎被转诊至神经外科。两例均进行了计算机断层扫描（CT）、CT脑池造影和磁共振成像等影像学检查。这些影像学研究发现颞叶通过一个骨缺损疝出，该骨缺损使中颅窝与蝶窦外侧隐窝相通。由于之前的内镜手术失败，两名患者均接受了经颅脑膨出修复术。手术过程中无并发症发生，术后2年和3年分别未再出现脑脊液漏复发。
蝶窦外侧隐窝内的脑膨出是一种罕见的情况，对于出现自发性脑脊液鼻漏的患者必须予以怀疑。位于圆孔内侧的先天性蝶窦内脑膨出似乎是由于施特恩贝格管持续存在所致。当经鼻入路先前失败时，经颅入路是一个不错的选择。
