Using an endoscopic endonasal approach makes it possible to identify all of the anatomical landmarks of the pterygopalatine fossa and almost all of the contiguous skull base areas.

The aim of this study is to define the indications to endoscopy versus other surgical procedures in the management of suprasellar arachnoid cysts from a personal series and an extensive literature review. Five symptomatic patients (two children and three adults) with suprasellar arachnoid cysts were treated by endoscopic fenestration in our neurosurgical unit. The endoscopic procedure consisted of ventricle-cyst-cisternostomy in three cases and ventricle-cystostomy in two. Four patients were cured after the endoscopic procedure alone, whereas another with rhinoliquorrhoea later required a craniotomy. The literature review includes 102 patients treated by endoscopic fenestration and 74 treated by other procedures, including microsurgical cyst resection through craniotomy (38 cases), shunt of the cyst (21 cases) and percutaneous ventricle-cystostomy (15 cases). Among the reviewed cases, the rate of cure or improvement was 90% (92 among 102 cases including ours) after endoscopy and 81% (60 among 74 cases) after other surgical procedures. The results of this study suggest that endoscopic ventricle-cyst cisternostomy is the best treatment for suprasellar arachnoid cysts, because it is less invasive, provides the best results and avoids shunt dependency in most cases.

In our experience, the injection of fibrin glue has proved to be effective in filling or sealing post-operative "dead spaces" and treating minor or initial CSF leaks resulting from procedures of transsphenoidal, cranial and spinal surgery, adding another possibility in the management of many of these dreadful complications.

Five patients with arachnoid cysts of the quadrigeminal cistern treated by endoscopic fenestration are reported and another eleven well-documented cases from the literature are reviewed. Among the five personal cases four were children and one was adult; the cyst fenestration was performed from the lateral ventricle in three cases and from the third ventricle in two. In four patients the endoscopic treatment resulted in clinical remission, whereas a two-month-old baby later required a shunt. The lateral ventricle-cystostomy and the third ventricle-cystostomy (according to the cyst extent) are the best endoscopic procedures, whereas the cyst fenestration through a suboccipital supracerebellar approach is no longer used. The rate of cured or improved patients after endoscopic surgery (14/16 or 87.5%) was rather similar to that of a group of twenty patients treated by traditional surgery (craniotomy and cyst excision and/or shunt) (85%). These data confirm that endoscopic fenestration of quadrigeminal cistern cysts must be performed as the first procedure because it is less invasive and avoids shunt dependency.

The endoscopic endonasal approach via the pterygopalatine fossa offers direct, minimally invasive access to the lateral recess of the sphenoid sinus, which can be monitored in each phase through consistent radiological imagery.