title: Accuracy of three-dimensional and two-dimensional ultrasonography for measurement of tumor volume in dogs with transitional cell carcinoma of the urinary bladder.
abstract: OBJECTIVE
  To determine the accuracy of 3-D and 2-D ultrasonography for quantification of tumor volume in dogs with transitional cell carcinoma (TCC) of the urinary bladder.
  
  
  METHODS
  10 dogs with biopsy-confirmed TCC.
  
  
  METHODS
  The urinary bladder of each dog was distended with saline (0.9% NaCl) solution (5.0 mL/kg), and masses were measured via 3-D and 2-D ultrasonography. Masses were also measured via 3-D ultrasonography after bladders were distended with 2.5 and 1.0 mL of saline solution/kg. Subsequently, the bladder was deflated and distended with CO(2) (5.0 mL/kg); CT was performed after IV contrast medium administration. Tumor volumes were calculated via 3-D ultrasonography, 2-D ultrasonography, and CT (reference method) and compared via ANOVA, Deming regression, and Bland-Altman plots. Repeated-measures ANOVA was used to assess effects of bladder distension on 3-D tumor volume measurements. Repeatability of measurements was estimated via the coefficient of variation for each method.
  
  
  RESULTS
  Repeatability was considered good for all 3 methods. There was no significant difference in tumor volume measurements obtained via 3-D ultrasonography at different degrees of urinary bladder distension. Results of Deming regression and Bland-Altman plots indicated excellent agreement between tumor volume measurement with 3-D ultrasonography and CT, but not between 2-D ultrasonography and CT.
  
  
  CONCLUSIONS
  Tumor volume in dogs with TCC of the urinary bladder was accurately measured via 3-D ultrasonography. Use of 3-D ultrasonography can provide a less expensive and more practical method for monitoring response to treatment than CT and was more accurate than 2-D ultrasonography.
authors.affiliation: Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA. jfnaught@purdue.edu
authors.forename: James F
authors.initials: JF
authors.lastname: Naughton
authors.forename: William R
authors.initials: WR
authors.lastname: Widmer
authors.forename: Peter D
authors.initials: PD
authors.lastname: Constable
authors.forename: Deborah W
authors.initials: DW
authors.lastname: Knapp
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002295:Carcinoma, Transitional Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary*; D003287:Contrast Media / Q000378:metabolism; D004283:Dog Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D004285:Dogs; D005260:Female; D021621:Imaging, Three-Dimensional / Q000295:instrumentation / Q000379:methods* / Q000662:veterinary; D007196:Indiana; D008297:Male; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000662:veterinary; D047368:Tumor Burden; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods* / Q000662:veterinary; D001743:Urinary Bladder / Q000000981:diagnostic imaging* / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary*
chemical_list: D003287:Contrast Media