title: Supracerebellar infratentorial approach to cavernous malformations of the brainstem: surgical variants and clinical experience with 45 patients.
abstract: OBJECTIVE
  The supracerebellar infratentorial (SCIT) approach can be performed at the midline (median variant), lateral to the midline (paramedian variant), or at the level of the angle formed by the transverse and sigmoid sinuses (extreme lateral variant). We analyzed our experience with SCIT approaches for the surgical treatment of cavernous malformations of the brainstem (CMBs).
  
  
  METHODS
  Demographic, clinical, radiologic, and surgical data from 45 patients (20 males and 25 females; mean age, 36.2 years) with CMBs surgically removed through SCIT approaches were reviewed retrospectively. Anatomic information was explored using cadaver head dissection.
  
  
  RESULTS
  Twenty-three lesions were in the midbrain, 3 were at the midbrain and extended to the thalamus, 9 were at the pontomesencephalic junction, and 10 were in the upper pons. All patients presented with hemorrhage. The median variant was used in 13 patients, the paramedian variant in 9, and the extreme lateral variant in 23. Intraoperatively, all CMBs were associated with a developmental venous anomaly. At last follow-up, 88% of the patients were the same or better. After a mean follow-up of 20 months, their mean Glasgow Outcome Scale score was 4.1.
  
  
  CONCLUSIONS
  SCIT approaches provide excellent exposure to CMBs located at the posterior incisural space, not only in the midline but also in the posterolateral surface of the upper pons and midbrain. Careful preoperative planning and neuronavigational assistance are needed to determine the best angle of attack and trajectory for SCIT approaches. Refined microsurgical techniques are paramount to achieve safe surgical removal of CMBs with good outcomes.
authors.affiliation: Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
authors.forename: Jean G
authors.initials: JG
authors.lastname: de Oliveira
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Lekovic
authors.forename: Sam
authors.initials: S
authors.lastname: Safavi-Abbasi
authors.forename: Cassius V
authors.initials: CV
authors.lastname: Reis
authors.forename: Ricardo A
authors.initials: RA
authors.lastname: Hanel
authors.forename: Randall W
authors.initials: RW
authors.lastname: Porter
authors.forename: Mark C
authors.initials: MC
authors.lastname: Preul
authors.forename: Robert F
authors.initials: RF
authors.lastname: Spetzler
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001933:Brain Stem / Q000473:pathology*; D002531:Cerebellum / Q000601:surgery*; D002648:Child; D003388:Cranial Fossa, Posterior / Q000601:surgery*; D003399:Craniotomy / Q000379:methods; D005073:Evoked Potentials, Somatosensory / Q000502:physiology; D005260:Female; D023261:Glasgow Outcome Scale; D006470:Hemorrhage / Q000209:etiology / Q000601:surgery; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000150:complications / Q000473:pathology* / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods*; D012189:Retrospective Studies; D055815:Young Adult