Timing of Postoperative CSF Leak after Endoscopic Skull Base Surgery in Patients with Obstructive Sleep Apnea.

Background There is little data regarding postoperative outcomes of patients with obstructive sleep apnea (OSA) undergoing skull base surgery. The purpose of this study is to determine an association between risk factors and proximity of cerebrospinal fluid (CSF) leak to surgery in patients with OSA undergoing endoscopic skull base surgery. Methods A retrospective review of neurosurgical inpatients, with and without OSA, at a tertiary care institution from 2002 to 2015 that experienced a postoperative CSF leak after undergoing endoscopic skull base surgery. Results Forty patients met inclusion criteria, 12 (30%) with OSA. OSA patients had significantly higher body mass index (BMI; median 39.4 vs. 31.7, p < 0.01) and were more likely to have diabetes (41.7 vs. 10.7%, p = 0.04) than non-OSA patients; otherwise there were no significant differences in clinical comorbidities. No patients restarted positive pressure ventilation (PPV) in the inpatient setting. The type of repair was not a significant predictor of the time from surgery to leak. Patients with OSA experienced postoperative CSF leak 49% sooner than non-OSA patients (Hazard Ratio 1.49, median 2 vs. 6 days, log-rank p = 0.20). Conclusion Patients with OSA trended toward leaking earlier than those without OSA, and no OSA patients repaired with a nasoseptal flap (NSF) had a leak after postoperative day 5. Due to a small sample size this trend did not reach significance. Future studies will help to determine the appropriate timing for restarting PPV in this high risk population. This is important given PPV's significant benefit to the patient's overall health and its ability to lower intracranial pressure.

Endoscopic Endonasal Resection of Orbital Apex Cavernous Hemangioma: 2-Dimensional Operative Video.

A 52-yr-old woman was referred to a tertiary medical center for evaluation of 2 yr of progressive visual symptoms and 1 yr of retro-orbital pressure. Her ophthalmologic exam was unrevealing except for mild asymmetrical impairment in color perception. A gadolinium contrast-enhanced magnetic resonance image of the head showed a left extraconal orbital apex lesion consistent with cavernous hemangioma. Computed tomography reveled bony remodeling of the medial-inferior orbital walls with superior orbital fissure expansion. The lesion was endoscopically resected and confirmed by pathological analysis. The endoscopic approach is demonstrated in detail, including correlation with cadaveric anatomic specimens‡. During the approach, a rescue nasoseptal flap was raised in case the orbit required further support after tumor resection, but was replaced as this was not needed. This patient had a brief period of postoperative diplopia, which resolved 1 wk after surgery. Her subjective visual deficits and pressure have also resolved. Advantages of the endoscopic approach include improved direct visualization of the lesion, lack of external skin incisions, avoidance of significant neurovascular retraction, and shorter hospital stays than alternative orbitotomy or craniotomy approaches. This 4-handed approach demands endoscopic expertise of 2 surgeons, and is often performed by rhinology-neurosurgery or rhinology-ophthalmology surgical teams. The risk of postoperative diplopia should be discussed with the patient during informed consent. ‡ Anatomic specimen photography courtesy Dr Peris-Celda.

Cortical surface intracranial electrodes identify clinically relevant seizures missed on scalp EEG after traumatic intracranial hemorrhage.

Seizures and other electrophysiological disturbances are an under-recognized cause of coma, focal deficits, and prolonged encephalopathy following subdural hematoma evacuation. In these patients, it is possible that seizures remain unrecognized on scalp EEG. It has been shown that a high burden of seizures and other electrophysiological disturbances exist following surgical evacuation and underlie the encephalopathy commonly seen in this patient population, predisposing them to medical complications and confounding estimates of prognosis. As part of a research protocol, we are performing intraoperative placement of cortical surface (non-parenchyma penetrating) intracranial EEG on patients who present after trauma and require emergent decompressive hemicraniectomy. In this case report of a patient with high-velocity traumatic epidural, subdural, and subarachnoid hemorrhages, we identified frequent non-convulsive seizures or seizure-like SIRPIDs with intracranial cortical surface monitoring that were not identified on simultaneous scalp EEG. Stimulation consistently triggered these electrographic seizures in addition to rhythmic lateralized periodic discharges. His mental status improved rapidly after resolution of these electrographic seizures shortly after increasing antiseizure medications, suggesting that they may have been contributing to his encephalopathy. More research is needed to determine the frequency of this phenomenon and determine whether treatment of such seizures improves patient outcomes.