Surgical nuances for removal of tuberculum sellae meningiomas with optic canal involvement using the endoscopic endonasal extended transsphenoidal transplanum transtuberculum approach

Abstract

<jats:p>Tuberculum sellae meningiomas frequently extend into the optic canals. Radical tumor resection including the involved dural attachment, underlying hyperostotic bone, and intracanalicular tumor in the optic canal offers the best chance of a Simpson Grade I resection to minimize recurrence. Decompression of the optic canal with removal of the intracanalicular tumor also improves visual outcome since this portion of the tumor is usually the cause of asymmetrical visual loss.</jats:p> <jats:p>The purely endoscopic endonasal extended transsphenoidal approach offers a direct midline trajectory and immediate access to tuberculum sellae meningiomas without brain retraction and manipulation of neurovascular structures. Although the endoscopic approach has been previously criticized for its inability to remove tumor within the optic canals, complete Simpson Grade I tumor removal including intracanalicular tumor, dural attachment, and involved hyperostotic bone can be achieved in properly selected patients. Excellent visualization of the suprasellar region and the inferomedial aspects of both optic canals allows for extracapsular, extraarachnoid dissection of the tumor from the critical structures using bimanual microsurgical dissection.</jats:p> <jats:p>In this report, the authors describe the operative nuances for removal of tuberculum sellae meningiomas with optic canal involvement using a purely endoscopic endonasal extended transsphenoidal (transplanum transtuberculum) approach. They specifically highlight the technique for endonasal bilateral optic nerve decompression and removal of intracanalicular tumor to improve postoperative visual function, as demonstrated in 2 illustrative cases. Special attention is also given to cranial base reconstruction to prevent CSF leakage using the vascularized pedicled nasoseptal flap.</jats:p>

Assessment of Mucocele Formation after Endoscopic Nasoseptal Flap Reconstruction of Skull Base Defects

“…[1][2][3][4][5][6][7][8] Although highly effective, these procedures often result in large SB defects that can lead to high-flow cerebrospinal fluid (CSF) leaks. These defects typically necessitate meticulous multilayer reconstruction to prevent postoperative failure.…”

Endoscopic extended transsphenoidal resection of tuberculum sellae meningiomas: nuances of neurosurgical technique

“…The details of the approach are well described [3][4][5]11,17,28 and will be only briefly reviewed here to emphasize variations of technique. The patient is positioned supine, either in pin fixation or a horseshoe headrest, depending on whether cranial manipulation is desired.…”

“…15,17,21 The neurosurgeon operates bimanually through 1 or both nares while an assistant either provides dynamic endoscopic visualization using a combination of 0° and 30° endoscopes or the endoscope is placed on a scope holder that can be frequently manipulated during the surgery. It is important to note that during bimanual microsurgery through the nares, if the 0° scope limits the working angle of the microsurgical instruments, the 30° scope can be used to move the head of the endoscope out of the way while providing adequate illumination and visualization.…”

“…This growth pattern results in displacement of the optic chiasm posteriorly and/or superiorly, 17 displacement of the pituitary stalk and sellar contents posteriorly, and displacement of the optic nerves laterally, particularly in the not uncommon case of tumor growth into the optic canals (Fig. 1).…”

“…Although involvement of the optic canals was initially thought to be a contraindication for endoscopic endonasal surgery, 6 adequate and safe exploration and resection of intracanalicular meningiomas has been demonstrated. 17 Indeed, exploration and graded opening of the medial optic canal is mandatory for ensuring complete tumor removal when canal involvement is demonstrated on preoperative high-resolution MR images.…”