Optimal indications and limitations of endoscopic transorbital superior eyelid surgery for spheno-orbital meningiomas

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>Spheno-orbital meningiomas (SOMs) are complicated tumors that involve multiple structures at initial presentation, such as the orbit, temporalis muscle, sphenoidal bone, cavernous sinus, and temporal or infratemporal fossa. The infiltrative growth and complexity of this type of meningioma make total resection impossible. In this study, the authors evaluated the surgical outcome of the endoscopic transorbital approach (eTOA) for SOM. In addition, they identified optimal indications for the use of eTOA and analyzed the feasibility of this approach as a minimally invasive surgery for SOMs of varying types and locations at presentation.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>Between September 2016 and December 2019, the authors performed eTOA in 41 patients with SOM with or without orbital involvement at 3 independent tertiary institutions. The authors evaluated the surgical outcomes of eTOA for SOM and investigated several factors that affect the outcome, such as tumor volume, tumor location, and the presence of lateral orbitotomy. Gross-total resection (GTR) was defined as complete resection of the tumor or intended subtotal resection except the cavernous sinus. This study was undertaken as a multicenter project (006) of the Korean Society of Endoscopic Neurosurgery (KOSEN-006).</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>There were 41 patients (5 men and 36 women) with a median age of 52.0 years (range 24–73 years). Twenty-one patients had tumors that involved the orbital structure, while 14 patients had tumors that presented at the sphenoidal bone along with other structures, such as the cavernous sinus, temporal fossa, and infratemporal fossa. Fifteen patients had the globulous type of tumor and 26 patients had the en plaque type. Overall, GTR was achieved in 21 of 41 patients (51.2%), and complications included CSF leaks in 2 patients and wound complications in 2 patients. Multiple logistic regression analysis showed that the en plaque type of tumor, absence of lateral orbital rim osteotomy, involvement of the temporal floor or infratemporal fossa, and involvement of the orbit and medial one-third of the greater sphenoidal wing were closely associated with lower GTR rates (p &lt; 0.05). Multivariate analysis revealed that the en plaque type of tumor and the absence of lateral orbital rim osteotomy were significant predictors for lower GTR rate.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>The en plaque type of SOM remains a challenge despite advances in technique such as minimally invasive surgery. Overall, clinical outcome of eTOA for SOM was comparable to the transcranial surgery. To achieve GTR, eTOA is recommended, with additional lateral orbital rim osteotomy for globulous-type tumors, without involving the floor of the temporal and infratemporal fossa.</jats:p></jats:sec>

Critical appraisal of minimally invasive keyhole surgery for intracranial meningioma in a large case series

“…The major limitation of this study is its retrospective nature, heterogenous meningioma patient population, and our selection bias for using these 6 keyhole approaches without a comparison cohort of patients treated with traditional skull base approaches or other relatively new minimally invasive approaches such as the endoscopic transorbital route [ 74 , 75 ]. We specifically did not compare clinical outcomes in the keyhole cohort to the 136 (41%) non-keyhole patient cohort.…”

Spheno-Orbital Meningiomas

“…Roser et al approached the classification of SOMs by first identifying the morphology of the meningioma (globoid, en plaque, and purely intraosseous), then detailing the involvement of the sphenoid wing and the CS [17]. Kong et al in turn proposed a slightly simplified version, focusing on the location of the tumor epicenter at the level of the greater wing of the sphenoid bone, which they divided into three thirds (medial, middle, and lateral) [18]. We suggest our own classification system derived from the previous schemes.…”

When multidisciplinary surgical trans-orbital approaches should be considered to reach the skull base

“…Literature on the topic is in steady growth with several anatomical comparative studies performed to value the feasibility of the transorbital approaches over endonasal and open patways 14,15 . Among published clinical series, the superior eyelid approaches to the middle skull base have been successfully used to manage spheno-orbital meningiomas (even if the en-plaque types remain a challenge) 16 and neoplastic diseases such as trigeminal schwannomas 17 and metastatic lesions 10 . Anyway, different Authors remark the limits of such approach, underlying the possibility that the unfamiliarity with the orbital anatomy may lead to orbital and globe injuries 13,18 .…”