A Case of Sellar Arachnoid Cyst Operated Using the Endoscopic Supraorbital Keyhole Approach

BACKGROUND AND IMPORTANCE: In recent years, sellar arachnoid cysts (ACs) have been increasingly treated using an endoscopic transnasal approach. It is important to connect the subarachnoid space with the AC to prevent recurrence; however, a high frequency of postoperative cerebrospinal fluid (CSF) leakage has been reported with the endoscopic transnasal approach, and the suitability of the endoscopic transnasal approach for treating sellar ACs is questionable to begin with. CLINICAL PRESENTATION: A man in his 40s underwent surgery for a sellar AC compressing the optic chiasm. The normal pituitary gland was compressed dorsally by the cyst, and an endoscopic supraorbital keyhole approach was adopted to reduce the risk of postoperative CSF leakage. A small incision was made in the right eyebrow, and a small craniotomy was performed. A rigid scope was used to approach the cyst and incise the arachnoid membrane of the prechiasmatic cistern and the anterior wall of the cyst. Postoperatively, the cyst shrank, and the preoperative visual field defects improved. The duration of the endoscopic manipulation was approximately 40 minutes. DISCUSSION: The endoscopic supraorbital keyhole approach eliminates the need to incise the dura mater of the anterior skull base and reduces the risk of CSF leakage compared with the transnasal approach. In addition, cumbersome dural reconstruction using fat and fascia is not required during the supraorbital keyhole approach, which reduces operation time. CONCLUSION: The endoscopic supraorbital keyhole approach may be more suitable than the transnasal approach for surgery of sellar ACs.