A Bland-Altman analysis of the bias between computed tomography and ultrasound prostate volume measurements.
This study assesses the agreement between computed tomography (CT) measurements of prostate volume and those obtained by ultrasound (US), a well-established non-invasive technique. Twenty-six patients aged between 58 and 74 years were evaluated for prostate seed implant therapy using both CT and US measurements. The level of agreement between these 2 methods, which were strongly correlated (R2 = 0.828; p < 0.0001), was determined through Bland-Altman analysis. The mean prostate volume (+/- one standard deviation) of the sample was 31.8 +/- 10.5 cc for the CT method and 27.0 +/- 8.2 cc for the US method. The prostate volumes obtained by CT were, on average, 17% larger than the corresponding volumes determined by US. The average bias between the 2 imaging methods is 4.80 cc or 15%, which is significantly larger than the clinically acceptable margin of 10%.
Gloi
Aime
A
Department of Radiation Oncology, St. Vincent Hospital, Green Bay, WI 54301, USA. agloi@stvgb.org
McCourt
Stephen
S
Zuge
Corrie
C
Goettler
AnnDrea
A
Schlise
Sally
S
Cooley
Greg
G
D000230:Adenocarcinoma / Q000000981:diagnostic imaging; D000368:Aged; D016477:Artifacts; D001918:Brachytherapy / Q000379:methods; D003287:Contrast Media; D003627:Data Interpretation, Statistical; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011467:Prostate / Q000000981:diagnostic imaging; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging*; D012107:Research Design; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed / Q000379:methods; D014463:Ultrasonography / Q000379:methods
D003287:Contrast Media; D007457:Iodine Radioisotopes