title: A novel MRI-compatible brain ventricle phantom for validation of segmentation and volumetry methods.
abstract: OBJECTIVE
  To create a standardized, MRI-compatible, life-sized phantom of the brain ventricles to evaluate ventricle segmentation methods using T(1) -weighted MRI. An objective phantom is needed to test the many different segmentation programs currently used to measure ventricle volumes in patients with Alzheimer's disease.
  
  
  METHODS
  A ventricle model was constructed from polycarbonate using a digital mesh of the ventricles created from the 3 Tesla (T) MRI of a subject with Alzheimer's disease. The ventricle was placed in a brain mold and surrounded with material composed of 2% agar in water, 0.01% NaCl and 0.0375 mM gadopentetate dimeglumine to match the signal intensity properties of brain tissue in 3T T(1) -weighted MRI. The 3T T(1) -weighted images of the phantom were acquired and ventricle segmentation software was used to measure ventricle volume.
  
  
  RESULTS
  The images acquired of the phantom successfully replicated in vivo signal intensity differences between the ventricle and surrounding tissue in T(1) -weighted images and were robust to segmentation. The ventricle volume was quantified to 99% accuracy at 1-mm voxel size.
  
  
  CONCLUSIONS
  The phantom represents a simple, realistic and objective method to test the accuracy of lateral ventricle segmentation methods and we project it can be extended to other anatomical structures.
authors.affiliation: Medical Biophysics, Medical Sciences Building, The University of Western Ontario, London, ON, Canada.
authors.forename: Amanda F
authors.initials: AF
authors.lastname: Khan
authors.forename: John J
authors.initials: JJ
authors.lastname: Drozd
authors.forename: Robert K
authors.initials: RK
authors.lastname: Moreland
authors.forename: Robert M
authors.initials: RM
authors.lastname: Ta
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Borrie
authors.forename: Robert
authors.initials: R
authors.lastname: Bartha
mesh_terms: D002552:Cerebral Ventricles / Q000033:anatomy & histology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity