title: Cavernous sinus lesions biopsy with neuronavigation and tip-cut needle.
abstract: BACKGROUND
  Transoval biopsy of cavernous sinus (CS) lesions is the last non-invasive diagnostic option in those 15% of patients in whom etiology remains unclear in spite of extensive neuroradiological imaging, clinical assessment, and laboratory evaluation. However, there are no guidelines defining indications and the most appropriate technique for this procedure.
  
  
  METHODS
  We present four patients in whom we performed X-ray and neuronavigation-assisted transoval CS biopsies using tip-cut needles.
  
  
  CONCLUSIONS
  The technique described allows the operator to determine the optimal angle for entering the CS, avoiding the complications due to distorted anatomy, and facilitating orientation once inside the CS. It reduces both radiation exposure as well as general anesthesia duration.
authors.affiliation: Department of Neurosurgery, Hospital de Santa Maria, Av. Professor Egas Moniz, 649-035, Lisbon, Portugal.
authors.forename: Martin
authors.initials: M
authors.lastname: Lorenzetti
authors.affiliation: Department of Neurosurgery, Hospital de Santa Maria, Av. Professor Egas Moniz, 649-035, Lisbon, Portugal.
authors.forename: Herculano
authors.initials: H
authors.lastname: Carvalho
authors.affiliation: Department of Neurosurgery, Hospital de Santa Maria, Av. Professor Egas Moniz, 649-035, Lisbon, Portugal.
authors.forename: Maria
authors.initials: M
authors.lastname: Cattoni
authors.affiliation: Department of Neurosurgery, Hospital de Santa Maria, Av. Professor Egas Moniz, 649-035, Lisbon, Portugal.
authors.forename: Antonio
authors.initials: A
authors.lastname: Gonçalves-Ferreira
authors.affiliation: Department of Neurology, Laboratory of Neuropathology, Hospital de Santa Maria, Instituto de Medicina Molecular, Lisbon, Portugal.
authors.forename: José
authors.initials: J
authors.lastname: Pimentel
authors.affiliation: Department of Neurosurgery, Hospital de Santa Maria, Av. Professor Egas Moniz, 649-035, Lisbon, Portugal.
authors.forename: Joao
authors.initials: J
authors.lastname: Antuñes
keywords: Cavernous sinus lesions; foramen ovale biopsy; minimally invasive biopsy; tip-cut needle; transoval approach