MR-Befundmuster der Prostata bei Patienten mit CPP Syndrom (chronic pelvic pain syndrome)

Abstract

To describe typical morphological patterns of abacterial prostatitis using magnetic resonance imagine (MRI) in chronic pelvic pain syndrome patients including spectroscopy. 18 patients (age range between 25 and 67 years, average 46.2 years) with recurrent chronic pelvic pain syndrome for at least 3 months were evaluated clinically in the urological department and included if there were no suspicious findings from endorectal digital palpation and if their PSA values were < 5 ng/ml. A retrospective analysis of these 18 patients with 30 contrast-enhanced MRI investigations with endorectal coils in 28 of 30 cases was performed with a 1.5T MRI. T 2w signal intensity (SI) and spectroscopy data (9 / 18 patients) were acquired for the normal peripheral zone, the central zone, for the peripheral zone suspected of inflammation and for the muscle including SI ratios for the unaltered and the suspicious inflammatory peripheral zone. Typical MR patterns of signal alterations suspected of inflammation of CPPS patients were able to be detected as T 2w hypointense triangular, stringy (n = 12, 66.6 %) contrast-enhancing signal alterations without a nodular shape with well circumscribed margins of the capsula and without pericapsular signal alterations. In 6 patients changes also had a triangular but more homogeneous aspect (33.3 %). Three patients had an additional periurethral uptake (16.6 %). T 2w SI measurements and T 2w SI ratios showed much lower values for the peripheral zone suspected of inflammation as compared to the normal peripheral zone of the prostate (277.29 STD 77.5 to 432.9 STD 112.02 and 4.94 STD 1.47 to 7.58 STD 2.01 respectively). The spectroscopic analysis of the signal alterations suspected of inflammation showed normal Cholin+Creatin/Citrate SI ratio values in 3 patients (SI < 0.5), ratios suspected of low grade cancer in 3 patients (SI 0.5 and < 0.7) and ratios suspected of intermediate grade prostate cancer in 3 patients (SI > 0.7 and < 3.0). We saw typical MR patterns in CPPS patients. However, spectroscopy can mimic findings of cancer so that the knowledge of typical morphological patterns and a solid clinical evaluation play a major role in the diagnosis of CPPS.