title: Calculating the Tumor Volumes in Vestibular Schwannomas: Are the ABC/2 and Volumetric Methods Comparable?
abstract: To assess the efficacy of the ABC/2 method for calculating the volume of vestibular schwannomas as compared with 3-D planimetric method.
  
  
  
  Retrospective.
  
  
  
  Fifty eight cases of pathologically confirmed sporadic vestibular schwannomas (VS) were analyzed. Tumors volumes were calculated for each tumor twice, once through semiautomated 3-D volumetric method and subsequently through ABC/2 (AP × ML × CC/2) methodology after calculating the maximal tumor dimensions in anteroposterior (AP), coronal (ML), and craniocaudal (CC) dimensions. Tumor volumes were initially correlated as a group and subsequently by dividing them into three groups using the Hannover classification.
  
  
  
  The two methodologies were highly correlated when tumors were analyzed as a group (rho = 0.913, p < 0.0001). In the sub-group analysis, tumor volumes were again strongly correlated for larger tumors (rho = 0.918, p < 0.0001) but the correlation progressively reduced as tumor volumes decreased.
  
  
  
  Given the ease and universal accessibility of linear measurement applications, the ABC/2 methodology is a robust substitute for calculating tumor volumes, especially for larger tumors.
authors.affiliation: *Department of Radiology †Department of Otolaryngology-Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa.
authors.forename: Girish
authors.initials: G
authors.lastname: Bathla
authors.forename: Bruno
authors.initials: B
authors.lastname: Policeni
authors.forename: Marlan R
authors.initials: MR
authors.lastname: Hansen
authors.forename: Kevin
authors.initials: K
authors.lastname: Berbaum
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000473:pathology*; D012189:Retrospective Studies; D047368:Tumor Burden