title: Minimally invasive biopsy of parasellar lesions: safety and clinical applications of the endoscopic, transnasal approach.
abstract: The base of the skull can be affected by a variety of tumours requiring a wide range of treatment modalities. In formulating a management plan, histological diagnosis can play an essential role. Existing methods of skull base biopsy, especially in the anatomically critical parasellar region, include either prolonged open skull base approaches or image-guided needle biopsies. The latter methods can be time-consuming and cannot reliably avoid surrounding critical neurovascular structures. The experience with an endoscopic, transnasal biopsy of parasellar tumours in selected patients is presented. A preliminary series of 11 patients harbouring parasellar lesions with some degree of extension to the sphenoid or maxillary sinus underwent endoscopic, transnasal biopsy. The procedure was diagnostic in all cases. There was no operative mortality and minimal morbidity only recorded. The biopsy results affected the patients' management and, based on these results, major skull base surgery was avoided in four cases. Direct endoscopic visualization prompted avoidance of a vascular catastrophe of an atypical vascular lesion. The endoscopic, transnasal biopsy appears to offer a number of advantages over existing methods in selected patients. It is minimally invasive as it employs the use of natural osseous corridors. Tissue sampling under direct visualization minimizes the risks of negative biopsies or damage to critical neurovascular structures. The use of additional imaging employed by image-guided needle biopsies in not necessary. When planning treatment of parasellar tumours, the endoscopic, transnasal route should be considered.
authors.affiliation: Oxford Skull Base Unit, Radcliffe Infirmary, Oxford, UK. dr_samandouras@hotmail.com
authors.forename: George
authors.initials: G
authors.lastname: Samandouras
authors.forename: Richard S C
authors.initials: RS
authors.lastname: Kerr
authors.forename: Chris A
authors.initials: CA
authors.lastname: Milford
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy / Q000379:methods; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008443:Maxillary Sinus / Q000473:pathology; D008875:Middle Aged; D009296:Nasal Cavity; D009361:Neoplasm Invasiveness / Q000473:pathology; D044582:Neuroendoscopes; D044583:Neuroendoscopy / Q000379:methods*; D012658:Sella Turcica; D019292:Skull Base Neoplasms / Q000473:pathology*; D013101:Sphenoid Sinus / Q000473:pathology