title: Independent predictors of morbidity after image-guided stereotactic brain biopsy: a risk assessment of 270 cases.
abstract: OBJECTIVE
  Image-guided stereotactic brain biopsy is associated with transient and permanent incidences of morbidity in 9 and 4.5% of patients, respectively. The goal of this study was to perform a critical analysis of risk factors predictive of an enhanced operative risk in frame-based and frameless stereotactic brain biopsy.
  
  
  METHODS
  The authors reviewed the clinical and neuroimaging records of 270 patients who underwent consecutive frame-based and frameless image-guided stereotactic brain biopsies. The association between preoperative variables and biopsy-related morbidity was assessed by performing a multivariate logistic regression analysis. Transient and permanent stereotactic biopsy-related morbidity was observed in 23 (9%) and 13 (5%) patients, respectively. A hematoma occurred at the biopsy site in 25 patients (9%); 10 patients (4%) were symptomatic. Diabetes mellitus (odds ratio [OR] 3.73, 95% confidence interval [CI] 1.37-10.17, p = 0.01), thalamic lesions (OR 4.06, 95% CI 1.63-10.11, p = 0.002), and basal ganglia lesions (OR 3.29, 95% CI 1.05-10.25, p = 0.04) were in'dependent risk factors for morbidity. In diabetic patients, a serum level of glucose that was greater than 200 mg/dl on the day of biopsy had a 100% positive predictive value and a glucose level lower than 200 mg/dl on the same day had a 95% negative predictive value for biopsy-related morbidity. Pontine biopsy was not a risk factor for morbidity. Only two (4%) of 45 patients who had epilepsy before the biopsy experienced seizures postoperatively. The creation of more than one needle trajectory increased the incidence of neurological deficits from 17 to 44% when associated with the treatment of deep lesions (those in the basal ganglia or thalamus; p = 0.05), but was not associated with morbidity when associated with the treatment of cortex lesions.
  
  
  CONCLUSIONS
  Basal ganglia lesions, thalamic lesions, and patients with diabetes were independent risk factors for biopsy-associated morbidity. Hyperglycemia on the day of biopsy predicted morbidity in the diabetic population. Epilepsy did not predispose to biopsy-associated seizure. For deep-seated lesions, increasing the number of biopsy samples along an established track rather than performing a second trajectory may minimize the incidence of morbidity. Close perioperative observation of glucose levels may be warranted.
authors.affiliation: Department of Neurosurgery, The Johns Hopkins School of Medicine, Baltimore, Maryland 21287, USA. mmcgirt1@jhmi.edu
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: McGirt
authors.forename: Graeme F
authors.initials: GF
authors.lastname: Woodworth
authors.forename: Alex L
authors.initials: AL
authors.lastname: Coon
authors.forename: James M
authors.initials: JM
authors.lastname: Frazier
authors.forename: Eric
authors.initials: E
authors.lastname: Amundson
authors.forename: Ira
authors.initials: I
authors.lastname: Garonzik
authors.forename: Alessandro
authors.initials: A
authors.lastname: Olivi
authors.forename: Jon D
authors.initials: JD
authors.lastname: Weingart
mesh_terms: D001480:Basal Ganglia Diseases / Q000150:complications; D001706:Biopsy / Q000009:adverse effects* / Q000379:methods*; D001786:Blood Glucose / Q000032:analysis; D001921:Brain / Q000473:pathology*; D048909:Diabetes Complications; D005260:Female; D006406:Hematoma / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D038361:Neuronavigation; D012044:Regression Analysis; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013238:Stereotaxic Techniques / Q000009:adverse effects*; D025321:Surgery, Computer-Assisted; D013786:Thalamic Diseases / Q000150:complications
chemical_list: D001786:Blood Glucose