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BACKGROUND AND OBJECTIVES: Bypass surgery has become one of the essential techniques in neurosurgery. The internal maxillary artery (IMAX) has emerged as an increasingly used donor vessel for large-caliber extracranial–intracranial bypass. However, the limited donor length reported in previously described techniques often necessitates the use of interposition grafts. This study describes a novel graftless direct IMAX–middle cerebral artery (MCA) bypass technique using a combined endoscopic sublabial transmaxillary and pterional approach. METHODS: Six silicone-injected, embalmed cadaveric heads were dissected in 3 stages: (1) endoscopic sublabial transmaxillary exposure of the IMAX, (2) microsurgical pterional exposure of the MCA divisions, and (3) graftless direct IMAX–MCA bypass. The diameter of the pterygopalatine segment of IMAX and the total available donor length were measured using digital calipers. The surgical corridor and vessel transposition were additionally demonstrated through anatomic modeling to support spatial orientation. RESULTS: The pterygopalatine segment of IMAX is defined via an endoscopic sublabial transmaxillary approach, transposed intracranially through a craniectomy performed superolateral to the foramen rotundum. Then direct graftless IMAX–MCA bypass was performed microscopically via pterional transsylvian approach. The mean diameter of the pterygopalatine segment of IMAX segment was 2.19 ± 0.34 mm (95% CI: 1.98-2.40 mm), and the total available donor length measured 5.40 ± 0.82 cm (95% CI: 4.88-5.91 cm). This length permitted tension-free transposition to the distal M1 without the need for interposition graft. CONCLUSION: This combined approach demonstrates the anatomic feasibility of a direct graftless large-caliber IMAX–MCA bypass by providing sufficient donor length.

Objective : Postoperative data on Cushing’s disease (CD) are equivocal in the literature. These discrepancies may be attributed to different series with different criteria for remission and variable follow-up durations. Additional data from experienced centers may address these discrepancies. In this study, we present the results obtained from 96 endoscopic transsphenoidal surgeries (ETSSs) for CD conducted in a well-experienced center.Methods : Pre- and postoperative data of 96 ETSS in 87 patients with CD were included. All cases were handled by the same neurosurgical team between 2014 and 2022. We obtained data on remission status 3−6 months postoperatively (medium-term) and during the latest follow-up (long-term). Additionally, magnetic resonance imaging (MRI) and pathology results were obtained for each case.Results : The mean follow-up duration was 39.5±3.2 months. Medium and long-term remission rates were 77% and 82%, respectively. When only first-time operations were considered, the medium- and long-term remission rates were 78% and 82%, respectively. The recurrence rate in this series was 2.5%. Patients who showed remission between 3−6 months had higher longterm remission rates than did those without initial remission. Tumors >2 cm and extended tumor invasion of the cavernous sinus (Knosp 4) were associated with lower postoperative remission rates.Conclusion : Adenoma size and the presence/absence of cavernous sinus invasion on preopera-tive MRI may predict long-term postoperative remission. A tumor size of 2 cm may be a supporting criterion for predicting remission in Knosp 4 tumors. Further studies with larger patient populations are necessary to support this finding.