Use of intraoperative ultrasound in differentiating adamantinomatous versus papillary craniopharyngiomas and guiding resection through the endoscopic endonasal route

Craniopharyngiomas (CPs) are surgically challenging tumors. The prevalence of BRAF mutation in papillary craniopharyngioma (PCP) and the positive response with BRAF-MEK inhibitors have shifted the treatment paradigm towards targeted therapy. However, maximal safe resection remains the goal, particularly for adamantinomatous craniopharyngioma (ACP). In this report, we describe two cases of CP where intraoperative ultrasonography (IOUS) was helpful in differentiating the subtype of CP, thus enabling intraoperative decision-making regarding the extent of resection. Additionally, IOUS images of three more (two PCP and one ACP) patients who underwent endoscopic endonasal resection for CPs were retrospectively evaluated. Each of these entities showed characteristic appearances on IOUS.