Influence of perfusion on high-intensity focused ultrasound prostate ablation: a first-pass MRI study.
Our aim was to evaluate the influence of regional prostate blood flow (rPBF) on high-intensity focused ultrasound (HIFU) treatment outcome. A total of 48 patients with clinically localized prostate cancer were examined by dynamic contrast-enhanced (DCE)-MRI prior to HIFU therapy. A prostate-specific antigen (PSA) nadir threshold of 0.2 ng/ml was used to define the populations of responders and nonresponders. A dedicated tracer kinetic model, namely "monoexponential plus constant" (MPC) deconvolution, was implemented to provide quantitative estimates of rPBF. The results were compared with those obtained by semiquantitative (steepest slope, mean gradient) and quantitative (Fermi deconvolution) approaches. Of the four methods studied, quantitative rPBF obtained by MPC deconvolution proved the most sensitive to the perfusion changes encountered in this study. Furthermore, blood-flow values obtained with MPC deconvolution in the prostate and muscle (12 +/- 8 and 5 +/- 3 ml/min/100 g, respectively) were in good agreement with literature data. The mean pretreatment rPBF obtained with MPC deconvolution was significantly higher in nonresponders compared to responders (16 +/- 9 vs. 10 +/- 6 ml/min/100 g), suggesting a correlation between baseline perfusion and treatment outcome. The present work describes and validates the use of dynamic MRI to estimate rPBF in patients, which in the future may help to refine the conduct of HIFU therapy.
Université de Lyon, Lyon, F-69003, France; INSA de Lyon, Villeurbanne, F-69621, France; Creatis CNRS, UMR 5220, Bron, F-69677, France; Inserm, U630, Bron, F-69677, France.
Marlène
M
Wiart
Université de Lyon, Lyon, F-69003, France; Inserm, U556, Lyon, F-69424, France.
Laura
L
Curiel
Université de Lyon, Lyon, F-69003, France; Inserm, U556, Lyon, F-69424, France.|Université de Lyon, Lyon, F-69003, France; Hospices Civils de Lyon, Edouard Herriot Hospital, Urology Department, Lyon, F-69003, France.
Albert
A
Gelet
Université de Lyon, Lyon, F-69003, France; Inserm, U556, Lyon, F-69424, France.|Université de Lyon, Lyon, F-69003, France; Université de Lyon 1, Faculté de Médecine Lyon Nord, Lyon, F-69003, France.|Université de Lyon, Lyon, F-69003, France; Hospices Civils de Lyon, Edouard Herriot Hospital, Department of Urinary and Vascular Imaging, Lyon, F-69003, France.
Denis
D
Lyonnet
Université de Lyon, Lyon, F-69003, France; Inserm, U556, Lyon, F-69424, France.
Jean-Yves
JY
Chapelon
Université de Lyon, Lyon, F-69003, France; Inserm, U556, Lyon, F-69424, France.|Université de Lyon, Lyon, F-69003, France; Université de Lyon 1, Faculté de Médecine Lyon Nord, Lyon, F-69003, France.|Université de Lyon, Lyon, F-69003, France; Hospices Civils de Lyon, Edouard Herriot Hospital, Department of Urinary and Vascular Imaging, Lyon, F-69003, France.
Olivier
O
Rouvière
D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010477:Perfusion; D011468:Prostatectomy / Q000379:methods*; D011471:Prostatic Neoplasms / Q000601:surgery; D036761:Ultrasound, High-Intensity Focused, Transrectal