ABSTRACT
PURPOSE: Prostatic urethral lift with UroLift is a minimally invasive approach to treat symptomatic benign prostatic hypertrophy. This device causes artifacts on prostate magnetic resonance images. Our aim was to evaluate the impact of artifact on prostate magnetic resonance image quality. MATERIALS AND METHODS: This was a single-center retrospective review of patients with UroLift who subsequently had prostate magnetic resonance imaging. Two readers graded UroLift artifact on each pulse sequence using a 5-point scale (1-nondiagnostic; 5-no artifact). Prostate Imaging Quality scores were assigned for the whole data set. The volume of gland obscured by artifact was measured. Linear and logistic regression models were used to identify predictors of poor image quality. RESULTS: Thirty-seven patients were included. Poor image quality occurs more in the transition zone than the peripheral zone (15% vs 3%), at base/mid regions vs the apex (13%, 9%, and 5%, respectively) and on diffusion-weighted images vs T2-weighted and dynamic contrast-enhanced sequences (27%, 0.3%, 0%, respectively; P < .001). Suboptimal image quality (ie, Prostate Imaging Quality score <2) was found in 16%-24% of exams. The percentage of gland obscured by the UroLift artifact was higher on diffusion-weighted images and dynamic contrast-enhanced sequences than T2-weighted (32%, 9%, and 6%, respectively; P < .001). CONCLUSIONS: UroLift artifact negatively affects prostate magnetic resonance image quality with greater impact in the mid-basal transition zone, obscuring a third of the gland on diffusion-weighted images. Patients considering this procedure should be counseled on the impact of this device on image quality and its potential implications for any image-guided prostate cancer workup.
ABSTRACT
PURPOSE: We evaluated the influence of 5-alpha reductase inhibitors (5-ARIs) on the performance of magnetic resonance imaging (MRI) for detection of Gleason grade group (GG) ≥2 prostate cancer, and on apparent diffusion coefficient (ADC) maps. MATERIALS AND METHODS: This single center, retrospective study included men who had MRI for initial detection or active surveillance of prostate cancer. The study group included 59 men who used for 5-ARIs for ≥12 months, and the control group included 59 men who were matched for both MRI indication and biopsy results. DeLong's test was used to compare the area under the receiver operating characteristic curve (AUC) for detection of GG ≥2 cancer between the groups. Wilcoxon rank sum test was used for comparison of lesions apparent diffusion coefficient (ADC) metrics between the groups. RESULTS: MRI accuracy in the study group (AUC=0.778) was not significantly different compared to the control group (AUC=0.821; 95% CI for difference 0.22-0.13; p=0.636). In the control group, all ADC metrics were lower in lesions with GG ≥2 cancer on biopsy than in those with GG 1 cancer or negative results (p=0.001-0.01). In the study group, this difference was significant only when the mean ADC of the lesions was normalized by the ADC of urine (p=0.044). CONCLUSIONS: Long-term exposure to 5-ARIs does not seem to impair the detection of significant cancer on MRI but may affect the ability of ADC metrics to discriminate between lesions that harbor significant cancer and those that harbor insignificant cancer or benign tissue.
