title: Application and machine accuracy of a new frameless computed tomography-guided stereotactic brain biopsy system in dogs.
abstract: The purpose of this study was to describe application and machine accuracy for a new computed tomography (CT) guided, frameless, stereotactic brain biopsy system in dogs. Heads from ten canine cadavers were secured to a bite-plate with six attached fiducial markers and imaged using CT. Fiducialized CT images were imported into stereotactic software and spherical phantom lesions between 3.9 and 5.5 mm in diameter were created in six locations. Infrared cameras and reflective markers were used to register fiducials to the reconstructed image set. Coordinates in the X, Y, and Z planes were identified for each lesion center. Iohexol (1.5 μl of 240 mgI/ml) was injected into the center of each lesion and CT scans were repeated. Pre- and postinjection CT images for each cadaver were fused using the system software. Application accuracy was calculated using the center of each phantom lesion and the center of each injected contrast material location. Machine accuracy was calculated using a phantom with known distances between four fixed points in the X, Y, and Z planes. Mean application accuracy in the first 5 cadavers was 4.3 mm (95% confidence interval [CI] 2.9-4.3 mm) and in the second 5 cadavers was 2.9 mm (95% CI 2-3.9 mm). The more superficial lesions were targeted significantly less accurately than the deeper lesions (P = 0.0183). Median machine accuracy was 0.1 mm and the range was 0.1-0.2 mm. Findings supported use of the new biopsy system for canine brain lesions >3.9 mm in diameter.
authors.affiliation: Veterinary Medicine and Biomedical Sciences, Small Animal Clinical Sciences, Texas A&M University, College Station, TX.
authors.forename: Amanda R
authors.initials: AR
authors.lastname: Taylor
authors.affiliation: Large Animal Clinical Sciences, Internal Medicine, Texas A&M University, College Station, TX.
authors.forename: Noah D
authors.initials: ND
authors.lastname: Cohen
authors.affiliation: Department of Pediatric Surgery, University of Texas-Houston Medical School, Houston, TX.
authors.forename: Stephen
authors.initials: S
authors.lastname: Fletcher
authors.affiliation: Large Animal Clinical Sciences, Radiology, Texas A&M University, College Station, TX.
authors.forename: John F
authors.initials: JF
authors.lastname: Griffin
authors.affiliation: Small Animal Clinical Sciences, Neurology/Neurosurgery, Texas A&M University, College Station, TX.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Levine
mesh_terms: D000818:Animals; D001706:Biopsy / Q000295:instrumentation / Q000379:methods* / Q000662:veterinary; D001921:Brain / Q000473:pathology*; D002102:Cadaver; D003287:Contrast Media / Q000737:chemistry; D004285:Dogs / Q000033:anatomy & histology*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation / Q000379:methods / Q000662:veterinary; D007472:Iohexol / Q000737:chemistry; D019047:Phantoms, Imaging / Q000662:veterinary; D012680:Sensitivity and Specificity; D013238:Stereotaxic Techniques / Q000295:instrumentation / Q000662:veterinary; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods* / Q000662:veterinary
chemical_list: D003287:Contrast Media; D007472:Iohexol
keywords: biopsy; brain; computed tomography; neuronavigation; stereotactic