J Neurosurg. 2026;145(4):1003-1012
Planning a skull base bypass requires more than identifying donor and recipient arteries: both anastomotic access and temporary clip placement must be accommodated. Kartum and colleagues describe modular exposures that connect difficult carotid segments through a single corridor. Their contribution is an anatomical framework for selected complex reconstructions, not evidence that these extensive approaches improve clinical outcomes.
Study and key findings
The investigators performed anterolateral skull base dissections and simulated bypasses in six formalin-fixed, silicone-injected cadaveric heads, examining 12 sides. Middle fossa approaches were combined with infratemporal extensions to expose donor vessels, recipient segments and clipping sites.
After mobilization of the mandibular condyle and lateral pterygoid muscle, removal of the tympanic vaginal process exposed the distal high cervical carotid and initial posterior vertical petrous segment. Additional styloid removal enlarged the working space and exposed adjacent lower cranial nerves.
Anterior petrosectomy improved access around the horizontal petrous carotid, while anterior clinoidectomy expanded exposure of the clinoidal and ophthalmic regions. The dissections demonstrated carotid-to-carotid interposition bypasses and maxillary artery donor options, including a direct maxillary-to-petrous carotid anastomosis.
A particularly relevant hazard was the glossopharyngeal nerve immediately behind the proximal clipping region near the cervicopetrous junction. The study also emphasized avoiding graft compression when restoring the mandibular condyle.
Interpretation and limitations
The operative decision is which combination of exposures provides the required donor, recipient and clipping access without unnecessary extension. These are salvage options for carefully selected lesions requiring carotid sacrifice, not routine first-line alternatives to endovascular treatment.
No clinical cases, quantitative vessel diameters, graft lengths or corridor measurements were provided. Cadaveric feasibility cannot establish patency, adequate flow or neurological safety; cerebral perfusion through the direct maxillary-to-petrous bypass remains uncertain. Several demonstrations involved nerve sacrifice, underscoring that anatomical exposure does not imply preserved function.
Clinical takeaway
Use this study as an anatomical planning and laboratory-training resource. Match exposure to the intended reconstruction, explicitly account for lower cranial nerves and graft routing, and assess collateral circulation and flow requirements separately. Greater exposure is valuable only when its expected benefit justifies the additional tissue disruption.