Compressed Sensing Radial Sampling MRI of Prostate Perfusion: Utility for Detection of Prostate Cancer

Abstract

Purpose To investigate the diagnostic performance of a dual-parameter approach by combining either volumetric interpolated breath-hold examination (VIBE)- or golden-angle radial sparse parallel (GRASP)-derived dynamic contrast agent-enhanced (DCE) MRI with established diffusion-weighted imaging (DWI) compared with traditional single-parameter evaluations on the basis of DWI alone. Materials and Methods Ninety-four male participants (66 years ± 7 [standard deviation]) were prospectively evaluated at 3.0-T MRI for clinical suspicion of prostate cancer. Included were 101 peripheral zone prostate cancer lesions. Histopathologic confirmation at MRI transrectal US fusion biopsy was matched with normal contralateral prostate parenchyma. MRI was performed with diffusion weighting and DCE by using GRASP (temporal resolution, 2.5 seconds) or VIBE (temporal resolution, 10 seconds). Perfusion (influx forward volume transfer constant [K^trans] and rate constant [K_ep]) and apparent diffusion coefficient (ADC) parameters were determined by tumor volume analysis. Areas under the receiver operating characteristic curve were compared for both sequences. Results Evaluated were 101 prostate cancer lesions (GRASP, 61 lesions; VIBE, 40 lesions). In a combined analysis, diffusion and perfusion parameters ADC with K^trans or K_ep acquired with GRASP had higher diagnostic performance compared with diffusion characteristics alone (area under the curve, 0.97 ± 0.02 [standard error] vs 0.93 ± 0.03; P < .006 and .021, respectively), whereas ADC with perfusion parameters acquired with VIBE had no additional benefit (area under the curve, 0.94 ± 0.03 vs 0.93 ± 0.04; P = .18and .50, respectively, for combination of ADC with K^trans and K_ep). Conclusion If used in a dual-parameter model, incorporating diffusion and perfusion characteristics, the golden-angle radial sparse parallel acquisition technique improves the diagnostic performance of multiparametric MRI examinations of the prostate. This effect could not be observed combining diffusing with perfusion parameters acquired with volumetric interpolated breath-hold examination. © RSNA, 2018.

Figure 1:

Flowchart outlines the selection of the final study population with inclusion and exclusion criteria within the defined observation window. DCE = dynamic contrast-agent enhanced, GRASP = golden-angle radial sparse parallel, mpMRI = multiparametric MRI, PCa = prostate cancer, PSA = prostate-specific antigen, VIBE = volumetric interpolated breath-hold examination.

Figure 2:

Perfusion data set acquired at volumetric interpolated breath-hold examination. Images in a 68-year-old man with a Gleason score of 8 (4 + 4) and prostate-specific antigen level of 7.4 (mg/L). (a) T2-weighted MR image shows hypointense signal of the prostate cancer lesion. (b) Apparent diffusion coefficient (ADC) map shows hypointense signal of the prostate cancer lesion with an ADC value of 0.91 mm²/sec ± 0.29. (c) Perfusion map shows influx forward volume transfer constant (K^trans) value of 0.26 min²¹ ± 0.15. (d) Perfusion map shows rate constant (K_ep) value of 0.46 min⁻¹ ± 0.30. Volume of interest = 2.13 cm³. Note the extension of volume-of-interest boundaries (green outlines) defined on ADC series into interface regions between normal and pathologic parenchyma on dynamic contrast-enhanced MR images.

Figure 3:

Perfusion data set acquired by using golden-angle radial sparse parallel method. Images in a 67-year-old man with a Gleason score of 8 (4 + 4) and a prostate-specific antigen level of 18.15 mg/L. (a) T2-weighted MR image shows hypointense signal of the prostate cancer lesion. (b) Apparent diffusion coefficient (ADC) map shows hypointense signal in the prostate cancer lesion; ADC = 1.12 mm²/sec ± 0.39. (c) Perfusion map shows influx forward volume transfer constant (K^trans; 0.25 min⁻¹ ± 0.21). (d) Perfusion map shows rate constant (K_ep; 1.79 min⁻¹ ± 0.97). Lesion volume = 2.32 cm³. There is an extension of volume-of-interest boundaries (green outlines) defined on ADC series into interface regions between normal and pathologic parenchyma on dynamic contrast-enhanced MR images.

Figure 4:

Quantitative assessment of combined diffusion MRI and dynamic contrast agent–enhanced MRI. Scatterplots display the data pairs of apparent diffusion coefficients (ADCs) with (a) influx forward volume transfer constant and (b) ADC with rate constant values. ADC values are on the x-axis and the perfusion parameters are on the y-axis. Horizontal and vertical lines represent the dual-parameter cutoff levels. Note that the cutoff levels on the basis of golden-angle radial sparse parallel (GRASP)–derived perfusion parameters combined with ADC allows a better differentiation (ie, less overlap) between normal and prostate parenchyma compared to cutoff levels on the basis of volumetric interpolated breath-hold examination (VIBE)–derived perfusion parameters combined with ADC.