BACKGROUND. Chordomas are primarily malignant tumors encountered at either end of the neural axis; the craniovertebral junction and the sacrococcygeal

Intraoperative neurophysiological monitoring during endoscopic, endonasal approaches to the skull base is both feasible and safe. Numerous reports have recently emerged from the literature evaluating the efficacy of different neuromonitoring tests during endonasal procedures, making them relatively well-studied. The authors report on a comprehensive, multimodality approach to monitoring the functional integrity of at risk nervous system structures, including the cerebral cortex, brainstem, cranial nerves, corticospinal tract, corticobulbar tract, and the thalamocortical somatosensory system during endonasal surgery of the skull base. The modalities employed include electroencephalography, somatosensory evoked potentials, free-running and electrically triggered electromyography, transcranial electric motor evoked potentials, and auditory evoked potentials. Methodological considerations as well as benefits and limitations are discussed. The authors argue that, while individual modalities have their limitations, multimodality neuromonitoring provides a real-time, comprehensive assessment of nervous system function and allows for safer, more aggressive management of skull base tumors via the endonasal route.

Endonasal procedures may be necessary during management of craniofacial trauma. When a skull base fracture is present, these procedures carry a high risk of violating the cranial vault and causing brain injury or central nervous system infection. A 52-year-old bicyclist was hit by an automobile at high speed. He sustained extensive maxillofacial fractures, including frontal and sphenoid sinus fractures (Fig. 1). He presented to the emergency room with brisk nasopharyngeal hemorrhage, and was intubated for airway protection. He underwent emergent stabilization of his nasal epistaxis by placement of a Foley catheter in his left nare and tamponade with the Foley balloon. A six-vessel angiogram showed no evidence of arterial dissection or laceration. Imaging revealed inadvertent insertion of the Foley catheter and deployment of the balloon in the frontal lobe (Fig. 2). The balloon was subsequently deflated and the Foley catheter removed. The patient underwent bifrontal craniotomy for dural repair of CSF leak. He also had placement of a ventriculoperitoneal shunt for development of post-traumatic hydrocephalus. Although the hospital course was a prolonged one, he did make a good neurological recovery. The authors review the literature involving violation of the intracranial compartment with medical devices in the settings of craniofacial trauma. Caution should be exercised while performing any endonasal procedure in the settings of trauma where disruption of the anterior cranial base is possible.

Objective. Primary intramedullary spinal germ cell tumors are exceedingly rare. As such, there are no established treatment paradigms. We describe our management for spinal germ cell tumors and a review of the literature.Clinical Presentation. We describe the case of a 45-year-old man with progressive lower extremity weakness and sensory deficits. He was found to have enhancing intramedullary mass lesions in the thoracic spinal cord, and pathology was consistent with an intramedullary germ cell tumor. A video presentation of the case and surgical approach is provided.Conclusion. As spinal cord germinomas are highly sensitive to radiation and chemotherapy, a patient can be spared radical surgery. Diverse treatment approaches exist across institutions. We advocate biopsy followed by local radiation, with or without adjuvant chemotherapy, as the optimal treatment for these tumors. Histological findings have prognostic value if syncytiotrophoblastic giant cells (STGCs) are found, which are associated with a higher rate of recurrence. The recurrence rate in STGC-positive spinal germinomas is 33% (2/6), whereas it is only 8% in STGC-negative tumors (2/24). We advocate limited volume radiotherapy combined with systemic chemotherapy in patients with high risk of recurrence. To reduce endocrine and neurocognitive side effects, cranio-spinal radiation should be used as a last resort in patients with recurrence.

Objectives To determine the anatomical relationships that may influence endonasal access to the upper cervical spine. Setting We retrospectively analyzed computed tomography of 100 patients at a single institution. Participants Participants included adults with imaging of the hard palate, clivus, and cervical spine without evidence of fracture, severe spondylosis, or previous instrumentation. Main Outcome Measures Morphometric analyses of hard palate length and both distance and angle between the hard palate and odontoid process were based on radiographic measurements. Descriptive zones were assigned to cervical spine levels, and endoscopic visualization was simulated with projected lines at 0, 30, and 45 degrees from the hard palate to the cervical spine. Results We found an inverse relationship between hard palate length and the lowest zone of the cervical spine potentially visualized by nasal endoscopy. The distance between the posterior tip of the hard palate and the odontoid tip, and the angle formed between the two, directly influenced the lowest possible cervical exposure. Conclusions Radiographic relationships between hard palate length, distance to the odontoid, and the angle formed between the two predict the limits of endonasal access to the cervical spine. These results are supported by cadaveric data in Part Two of this study.