Extracranial-to-Intracranial Bypass Using Radial Artery Grafting for Complex Skull Base Tumors: Technical Note

The management of complex skull base tumors that incorporate large intracranial vessels poses challenging questions. Patients who fail initial surgical resection and adjunctive therapies (i.e., radiosurgery) who present with tumor regrowth may be candidates for parent vessel occlusion and total tumor resection in combination with extracranial-to-intracranial (EC-IC) bypass to augment the sacrificed vessel territory. In this technical report, we delineate the surgical technique of performing an EC-IC bypass using a radial artery graft. Our protocol of simultaneous cranial, neck, and forearm dissections by the surgical team to perform this procedure is described in detail

Meckel's Cave

OBJECTIVE: To review the microsurgical anatomy of Meckel's cave, a detailed knowledge of which is a prerequisite to devising an appropriate surgical strategy and performing successful surgery

Working area and angle of attack in three cranial base approaches: Pterional, orbitozygomatic, and maxillary extension of the orbitozygomatic approach

OBJECTIVE: This study was designed to quantify the operative exposure obtained in the pterional, orbitozygomatic, and modified orbitozygomatic with maxillary extension surgical approaches. METHODS: The pterional and orbitozygomatic approaches and a variation of the orbitozygomatic osteotomy that included an extra centimeter of bone resection in the inferior direction ( maxillary extension ) were performed on cadaveric heads. For each surgical exposure, the working area was determined by using triangles defined with anatomic points. The angle of attack of the approaches for the same target point was determined with the use of a robotic microscope. RESULTS: The maximum allowable angle of attack was significantly greater with the orbitozygomatic approach (37.2 ± 4.7 degrees) than that with the pterional approach (27.1 ± 4.3 degrees) (P \u3c 0.001). The angle of attack with the maxillary extension (42.0 ± 4.9 degrees) was significantly greater than that with the orbitozygomatic approach (P \u3c 0.001). The working areas were 281, 343, and 371 mm2 for the pterional, orbitozygomatic, and maxillary extension approaches, respectively. The orbitozygomatic approach with maxillary extension had a significantly larger working area than the pterional approach (P = 0.011). CONCLUSION: Increments in bony removal open a wider angle in which to work more than they increase the actual amount of working area. Increasing the amount of bone removed by using an orbitozygomatic approach instead of a pterional approach converts a narrow space into a wide portal, allowing surgeons to work closer to the surgical target while decreasing the need for brain retraction. Extending the orbitozygomatic approach into the maxillary region also improves the exposure area and angle, but less significantly

Change of daily process measures over the study period among the whole cohort and in subgroups of ICUs with baseline spontaneous trial (SAT) compliance of >50% and ≤50.

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Outcomes.

Outcomes.</p

List of participating sites and ethics committee approvals.

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Data measures definitions.

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