Dynamic contrast‐enhanced MRI in normal and abnormal prostate tissues as defined by biopsy, MRI, and 3D MRSI

Abstract

This study characterized dynamic contrast-enhanced (DCE) MRI of prostate tissues: cancerous peripheral zone (PZ), normal PZ, stromal benign prostatic hyperplasia (BPH), and glandular BPH. MRI, MRSI, and DCE MRI were performed on 25 patients. Tissues were identified with MRI, MRSI, and (when available) biopsy results. Motion between MRI and DCE MRI, and within DCE MRI was assessed and manually corrected. To assess tissue and patient effects, native T 1 's were measured in 12 of 25 patients, and DCE MRI results were normalized to muscle enhancement. Regions of cancer had a higher peak enhancement (P < 0.006), faster enhancement rate (P < 0.0008), and faster washout slope (P < 0.05) than normal PZ tissues. Stromal BPH had the fastest enhancement rate (P < 0.003) of all tissues and tended to have the greatest enhancement. Intersequence motion averaged 2.6 mm and reached 7.9 mm. Motion within DCE MRI was generally minimal (<2 pixels), but one case showed a large shift that would have confounded the results. Native T 1 's were similar across the prostatic tissues. Interpatient variability in DCE MRI was only partially reduced by normalization to muscle. DCE MRI of the prostate discriminated PZ cancer from normal PZ tissues and predominantly stromal and glandular BPH. Magn Reson Med 53:249 -255, 2005.

Pancreatic perfusion of healthy individuals and type 1 diabetic patients as assessed by magnetic resonance perfusion imaging

“…In the last few years we have seen a technological leap in non-invasive imaging technologies such as magnetic resonance (MR) imaging (MRI). Thus, there is an exciting opportunity to apply the new imaging techniques to the pancreatic beta cell [3][4][5][6][7].…”

Benign prostatic hyperplasia: Evaluation of T1, T2, and microvascular characteristics with T1‐weighted dynamic contrast‐enhanced MRI

“…These symptoms can have a significant effect on quality of life and can eventually lead to acute urinary retention, which requires surgical intervention (9). Measuring baseline microvascular parameters of BPH is valuable because distinguishing BPH, cancer, and normal tissue can be difficult, often requiring the use of several different techniques in consensus (10). By comparing these measurements with values estimated in cancer and normal tissue (6,11), suitable parameters for differential diagnosis of BPH may be identified.…”

Semiquantitative imaging measurement of baseline and vasomodulated normal prostatic blood flow using sildenafil

“…On the other hand, Preziosi et al 3 showed significant differences for prostate cancer in mean tumor maximal enhancement, mean tumor rise time and greatest washout slope versus normal prostate. The nonspecificity was emphasized by Nowlrowski et al, 4 who reported that maximal intensity enhancement and fastest peak occurs with stromal hyperplasia exceeding that of even cancer. Padhani et al 5 showed no peak enhancement differences, permeability or leakage modeling parameters between the medial zone and cancer.…”

“…[2][3][4][5][6] The angiogenesis of prostatic cancer stimulates increased vessel growth and density (maximum vessel density) as compared to normal tissue. 1,2 Accordingly, DCE MRI of the tumor tissue demonstrates increased signal intensity reflecting the increased number of tumor blood vessels.…”

“…The shortcoming of the current technique is the overlap of findings with prostatitis and cancer, because both can show increased signal intensity owing to increased blood flow. [2][3][4][5][6] A potential method of improving the differentiation of the two may be the use of vasoactive drugs that can induce characteristic changes in normal and tumor vessels. [7][8][9][10] Although not yet used in imaging, authors have shown in animal models that the vasodilators and vasoconstrictors cause the corresponding reaction in the normal vessels whereas tumor vessels do not react.…”