Endonasal endoscopic approach to the pterygopalatine and infratemporal fossae.

The pterygopalatine fossa and infratemporal fossa are spaces located under the skull base, housing important neurovascular structures. Surgical access to these spaces is challenging because of their deep location and complex anatomy. Their surgical access has been classically carried out through multiple craniofacial approaches until the advent of endoscopic endonasal surgery at the end of the XXth century. Our goal is to describe the transmaxillary-transsphenoidal-transpterygoid approach to the pterygopalatine and infratemporal fossae through endonasal endoscopic surgery based on anatomo-surgical dissection and an illustrative clinical case. We conclude that after careful radiologic evaluation of the feasibility of this technique, the endonasal endoscopic access to these spaces for tumor resection is efficient with reduced surgical morbidities. The endonasal approach is versatile and can be fashioned according to the nature and extent of the lesion.

Intraoperative fiber-optic endoscopy for ventricular catheter insertion.

OBJECTIVE: Ventricular catheter placement is a common neurosurgical procedure often resulting in inaccurate intraventricular positioning. We conducted a comparison of the accuracy of endoscopic and conventional ventricular catheter placement in adults. METHODS: A retrospective analysis of data was performed on 37 consecutive patients undergoing ventriculo-peritoneal shunt (VPS) insertion with endoscopy and 40 randomly selected, unmatched patients undergoing VPS insertion without endoscopy, for the treatment of hydrocephalus of varied etiology. A grading system for catheter tip position was developed consisting of five intraventricular zones, V1 -V5, and three intraparenchymal zones, A, B, C. Zones V1 for the frontal approaches and V1 or V2 for the occipital approaches were the optimal catheter tip locations. Postoperative scans of each patient were used to grade the accuracy of ventricular catheter placement. RESULTS: Seventy-six percent of all endoscopic ventricular catheters were in zone V1 and 100% were within zones V1-V3. No endoscopically inserted catheters were observed in zones V4, V5 or intraparenchymally. Thirty-eight percent of the conventionally placed catheters were in zone V1, 53% in zones V1-3 and 15% intraparenchymally. There was a statistically significant difference in the percentage of catheters in optimal location versus in any other location, favoring endoscopic guidance (p<0.001). CONCLUSION: We conclude that endoscopic ventricular catheter placement provides improved positioning accuracy than conventional techniques.

Fenestration of the posteroinferior cerebellar artery: case report.

OBJECTIVE AND IMPORTANCE: Fenestrations of cerebral arteries are rare, but very important to diagnose given their high association with saccular aneurysms. We present the first reported case of a fenestration of the posteroinferior cerebellar artery (PICA). CLINICAL PRESENTATION: A 62-year-old man who presented with a subarachnoid hemorrhage underwent repeated four-vessel cerebral angiography. An isolated right PICA abnormality consistent with a dissection or fenestration was revealed. INTERVENTION: The patient underwent surgical exploration of his PICA, which confirmed a PICA fenestration without an associated saccular aneurysm. The fenestration was wrapped with cotton. CONCLUSION: Our case report illustrates the novel anatomic finding of a fenestration of the PICA. Knowledge of this entity would be helpful in the differential diagnosis of a posterior fossa subarachnoid hemorrhage.