title: Comparing computed tomography localization with daily ultrasound during image-guided radiation therapy for the treatment of prostate cancer: a prospective evaluation.
abstract: In the present paper, we describe the results of a prospective trial that compared isocenter shifts produced by BAT Ultrasound (Nomos, Sewicky, PA) to those produced by a computed tomography (CT) unit in the treatment room to aid in positioning during image-guided radiation therapy. The trial included 15 consecutive patients with localized prostate cancer. All patients underwent CT and MR simulation immobilized supine in an Alpha Cradle and were treated with intensity-modulated radiation therapy. BAT Ultrasound was used daily to correct for interfraction motion by obtaining shift in the x, y, and z directions. Two days per week during therapy, CT scans blinded to the ultrasound shifts were obtained and recorded. We analyzed 218 alignments from the 15 patients and observed a high level of correlation between the CT and ultrasound isocenter shifts (correlation coefficients: 0.877 anterior-posterior, 0.842 lateral, and 0.831 superior-inferior). The systematic differences were less than 1 mm, and the random differences were approximately 2 mm. The average absolute differences, including both systemic and random differences, were less than 2 mm in all directions. The isocenter shifts generated by using a CT unit in the treatment room correlate highly with shifts produced by the BAT Ultrasound system.
authors: Fox Chase Cancer Center, Department of Radiation Oncology, Philadelphia, Pennsylvania, U.S.A.
authors: Steven J
authors: SJ
authors: Feigenberg
authors: Fox Chase Cancer Center, Department of Radiation Oncology, Philadelphia, Pennsylvania, U.S.A.
authors: Kamen
authors: K
authors: Paskalev
authors: Fox Chase Cancer Center, Department of Radiation Oncology, Philadelphia, Pennsylvania, U.S.A.
authors: Shawn
authors: S
authors: McNeeley
authors: Fox Chase Cancer Center, Department of Radiation Oncology, Philadelphia, Pennsylvania, U.S.A.
authors: Eric M
authors: EM
authors: Horwitz
authors: Fox Chase Cancer Center, Department of Radiation Oncology, Philadelphia, Pennsylvania, U.S.A.
authors: Andre
authors: A
authors: Konski
authors: Fox Chase Cancer Center, Department of Radiation Oncology, Philadelphia, Pennsylvania, U.S.A.
authors: Lu
authors: L
authors: Wang
authors: Fox Chase Cancer Center, Department of Radiation Oncology, Philadelphia, Pennsylvania, U.S.A.
authors: Charlie
authors: C
authors: Ma
authors: Fox Chase Cancer Center, Department of Radiation Oncology, Philadelphia, Pennsylvania, U.S.A.
authors: Alan
authors: A
authors: Pollack
mesh_terms: D000328:Adult; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000532:radiotherapy*; D011881:Radiotherapy, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome; D014463:Ultrasonography / Q000379:methods*
references: Int J Radiat Oncol Biol Phys. 2001 Jul 15;50(4):947-51
references: 11429222
references: J Clin Oncol. 2000 Dec 1;18(23):3904-11
references: 11099319
references: Int J Radiat Oncol Biol Phys. 1999 Mar 1;43(4):719-25
references: 10098426
references: Int J Radiat Oncol Biol Phys. 2004 Jun 1;59(2):380-5
references: 15145151
references: Comput Aided Surg. 2000;5(4):289-95
references: 11029161
references: Urology. 2000 Jan;55(1):73-8
references: 10654898
references: Int J Radiat Oncol Biol Phys. 2002 Aug 1;53(5):1130-8
references: 12128112
references: Int J Radiat Oncol Biol Phys. 1998 Jul 15;41(5):1079-86
references: 9719118
references: Int J Radiat Oncol Biol Phys. 2004 Jun 1;59(2):595-601
references: 15145181
references: Int J Radiat Oncol Biol Phys. 1991 Jun;20(6):1317-24
references: 2045306
references: Int J Radiat Oncol Biol Phys. 2002 Aug 1;53(5):1124-9
references: 12128111
references: Int J Radiat Oncol Biol Phys. 2002 Aug 1;53(5):1117-23
references: 12128110
references: Int J Radiat Oncol Biol Phys. 2003 Jun 1;56(2):436-47
references: 12738318
references: Int J Radiat Oncol Biol Phys. 2001 May 1;50(1):265-78
references: 11316572
references: Int J Radiat Oncol Biol Phys. 2002 Jul 1;53(3):757-65
references: 12062622