Interactive image-guided pituitary surgery. An experience of 101 procedures.

This paper reports on a series of 101 pituitary region operations performed using image guidance technology in the Department of Neurosurgery, Frenchay hospital, Bristol, UK between 1992-1997. The cases form part of an overall series of image guided surgery of 1,112 cases performed during that time. The systems used were the ISG/Elekta Viewing Wand and the Sofamor Danek StealthStation. Thirty-five tumors had a diameter of > 2.5 cm and 12 > 5 cm. The clinical indications for surgery were: visual failure (n = 47), acromegaly (n = 22). Cushing syndrome (n = 6), hyperprolactinemia (n = 1), hyposecretion syndromes (n = 8), raised intracranial pressure/CSF leak (n = 13). Three cases were operated on because of radiological evidence of tumor progression without symptoms. Eighty-five patients had skull base procedures (56 transnasal routes, 16 transsphenoidal approaches, 13 sphenoid fenestrations), 16 underwent craniotomy. Operating times and postoperative bed stay were shortest the more minimally invasive the procedure. Sixty-eight percent of patients presenting with visual failure improved postoperatively. Surgery produced biochemical "cure" in 41% of patients with hypersecretion syndromes. Fifty percent of patients with hypopituitary syndromes improved endocrinologically postoperatively. Twenty-five complications were noted: 9 rhinorrheas, 5 diabetes insipidus, 3 postoperative epilepsies, 3 induced visual deteriorations and pituitary insufficiency. There were 2 deaths. Image guidance technology is applicable to pituitary surgery, particularly in four situations: i) orientation in difficult skull base approaches e.g. reoperations, paediatric cases, non pneumatised sphenoid, microadenomas, carotid arteries medially placed, ii) in craniotomies to customize the surgical approach, locate different parts of a tumor and identify critical anatomy related to the tumor, iii) in the planning and execution of minimally invasive approaches to the pituitary fossa (sphenoid fenestration, transnasal approach), iii) endoscopy.