MRI of shoulder girdle in polymyalgia rheumatica: inflammatory findings and their diagnostic value.

BACKGROUND: Non-synovial inflammation as detected by MRI is characteristic in polymyalgia rheumatica (PMR) with potentially high diagnostic value. OBJECTIVE: The objective is to describe inflammatory MRI findings in the shoulder girdle of patients with PMR and discriminate from other causes of shoulder girdle pain. METHODS: Retrospective study of 496 contrast-enhanced MRI scans of the shoulder girdle from 122 PMR patients and 374 non-PMR cases. Two radiologists blinded to clinical and demographic information evaluated inflammation at six non-synovial plus three synovial sites for the presence or absence of inflammation. The prevalence of synovial and non-synovial inflammation, both alone and together with clinical information, was tested for its ability to differentiate PMR from non-PMR. RESULTS: A high prevalence of non-synovial inflammation was identified as striking imaging finding in PMR, in average 3.4±1.7, mean (M)±SD, out of the six predefined sites were inflamed compared with 1.1±1.4 (M±SD) in non-PMR group, p<0.001, with excellent discriminatory effect between PMR patients and non-PMR cases. The prevalence of synovitis also differed significantly between PMR patients and non-PMR cases, 2.5±0.8 (M±SD) vs 1.9±1.1 (M±SD) out of three predefined synovial sites, but with an inferior discriminatory effect. The detection of inflammation at three out of six predefined non-synovial sites differentiated PMR patients from controls with a sensitivity/specificity of 73.8%/85.8% and overall better performance than detection of synovitis alone (sensitivity/specificity of 86.1%/36.1%, respectively). CONCLUSION: Contrast-enhanced MRI of the shoulder girdle is a reliable imaging tool with significant diagnostic value in the assessment of patients suffering from PMR and differentiation to other conditions for shoulder girdle pain.

Magnetic resonance imaging in polymyalgia rheumatica-contrast enhancement is not always needed.

BACKGROUND: Extracapsular inflammation at entheseal sites in the pelvic girdle as demonstrated by magnetic resonance imaging (MRI) was shown to be useful as an additional tool for diagnosing polymyalgia rheumatica (PMR). However, it is unclear whether MRI needs to be performed with contrast enhancement or whether oedema-sensitive sequences are sufficient. OBJECTIVE: To evaluate the performance of T2w TIRM (turbo inversion recovery magnitude) imaging compared to fat-saturated contrast-enhanced (ce) T1w at predefined pelvic sites to detect extracapsular inflammation in patients with PMR. METHODS: A total of 120 pelvic MRIs of patients with pelvic girdle pain, 40 with clinically diagnosed PMR and 80 controls, were retrospectively scored by three blinded radiologists separately evaluating the MRI with and without contrast enhancement at 19 previously defined pelvic structures. The intra- and interrater reliability and the diagnostic performance of both techniques were statistically analysed and evaluated. RESULTS: The detection of inflammatory MRI signals correlated moderately between both techniques (Cohen's κ 0.583). With ceT1w imaging 20.7% more sites were detected as inflamed compared to T2w TIRM in PMR patients. Inter- and intrareader reliability was superior with ceT1w imaging. If the inflammatory signal was detected at three sites bilaterally including the origin of the rectus femoris muscle or adductor longus muscle, the sensitivity and specificity was 100% and 97.1% by ceT1w imaging vs. 80.8% and 93.3% by T2w TIRM, respectively. CONCLUSION: Contrast enhancement is superior to oedema-sensitive MRI in the detection of extracapsular inflammation in PMR. However, using T2w TIRM also detects many but not all PMR cases.

Diagnostic capability of contrast-enhanced pelvic girdle magnetic resonance imaging in polymyalgia rheumatica.

OBJECTIVE: There is currently no diagnostic test for PMR. A characteristic pattern of extracapsular inflammation as assessed by contrast-enhanced MRI (ceMRI) has recently been described in the pelvis of patients with PMR. We aimed to evaluate the performance of inflammatory ceMRI signals at predefined pelvic sites as a diagnostic test for PMR. METHODS: Pelvic MRI scans of patients with pelvic girdle pain (n = 120), including 40 patients with an expert diagnosis of PMR and 80 controls with other reasons for pelvic pain were scored by three blinded radiologists, who evaluated the degree of contrast enhancement at 19 predefined tendinous and capsular pelvic structures. Different patterns of involvement were analysed statistically. RESULTS: The frequency of bilateral peritendinitis and pericapsulitis including less common sites, such as the proximal origins of the m. rectus femoris and m. adductor longus, differed significantly between PMR cases and controls: 13.4 ± 2.7 vs 4.0 ± 2.3. A cut-off of ≥10 inflamed sites discriminated well between groups (sensitivity 95.8%, specificity 97.1%). Bilateral inflammation of the insertion of the proximal m. rectus femoris or adductor longus tendons together with ≥3 other bilaterally inflamed sites performed even better (sensitivity 100%, specificity 97.5%). CONCLUSION: This study confirms that a distinctive MRI pattern of pelvic inflammation (bilateral peritendinitis and pericapsulitis and the proximal origins of the m. rectus femoris and m. adductor longus) is characteristic for PMR. The high sensitivity and specificity of the set of anatomical sites evaluated suggests their clinical usefulness as a confirmatory diagnostic test.

Detecting Prostate Cancer.

BACKGROUND: When prostate cancer is suspected, the prostate gland is biopsied with the aid of transrectal ultrasound (TRUS). The sensitivity of prostatic biopsy is about 50%. The fusion of magnetic resonance imaging (MRI) data with TRUS enables the targeted biopsy of suspicious areas. We studied whether this improves the detection of prostate cancer. METHODS: 168 men with suspected prostate cancer underwent prostate MRI after a previous negative biopsy. Suspicious lesions were assessed with the classification of the Prostate Imaging Reporting and Data System and biopsied in targeted fashion with the aid of fused MRI and TRUS. At the same sitting, a systematic biopsy with at least 12 biopsy cores was performed. RESULTS: Prostate cancer was detected in 71 patients (42.3%; 95% CI, 35.05-49.82). The detection rate of fusion-assisted targeted biopsy was 19% (95% CI, 13.83-25.65), compared to 37.5% (95% CI, 30.54-45.02) with systematic biopsy. Clinically significant cancer was more commonly revealed by targeted biopsy (84.4%; 95% CI, 68.25-93.14) than by systematic biopsy (65.1%; 95% CI, 52.75-75.67). In 7 patients with normal MRI findings, cancer was detected by systematic biopsy alone. Compared to systematic biopsy, targeted biopsy had a higher overall detection rate (16.5% vs. 6.3%), a higher rate of infiltration per core (30% vs. 10%), and a higher rate of detection of poorly differentiated carcinoma (18.5% vs. 3%). Patients with negative biopsies did not undergo any further observation. CONCLUSION: MRI/TRUS fusion-assisted targeted biopsy improves the detection rate of prostate cancer after a previous negative biopsy. Targeted biopsy is more likely to reveal clinically significant cancer than systematic biopsy; nevertheless, systematic biopsy should still be performed, even if the MRI findings are negative.

Impact of real-time elastography on magnetic resonance imaging/ultrasound fusion guided biopsy in patients with prior negative prostate biopsies.

PURPOSE: The fusion of multiparametric resonance imaging and ultrasound has been proven capable of detecting prostate cancer in different biopsy settings. The addition of real-time elastography promises to increase the precision of the outcome of targeted biopsies. We investigated whether real-time elastography improves magnetic resonance imaging/transrectal ultrasound fusion targeted biopsy in patients after previous negative biopsies. MATERIALS AND METHODS: Prospectively 121 men underwent 3T magnetic resonance imaging. Using magnetic resonance imaging/real-time elastography fusion every suspicious lesion was characterized according to its tissue density and sampled by 2 fusion guided targeted biopsies. Additionally, all patients underwent 12-core systematic biopsy. The detection rate of clinically significant and insignificant cancers was compared between targeted und systematic biopsies. The accuracy to predict high grade prostate cancer was evaluated for with the PI-RADS scoring system and compared to the magnetic resonance imaging/real-time elastography fusion score. RESULTS: Overall prostate cancer was detected in 52 patients (43%). Targeted fusion guided biopsy revealed prostate cancer in 32 men (26.4%) and systematic biopsy in 46 (38%). The proportion of clinically significant cancers was higher for targeted biopsy (90.6%) compared to systematic biopsy (73.9%). The detection rate per core was higher for targeted biopsies (14.7%) compared to systematic biopsies (6.5%, p <0.001). The prediction of biopsy result according to magnetic resonance imaging/real-time elastography fusion was better (AUC 0.86) than magnetic resonance imaging alone (AUC 0.79). Sensitivity and specificity for magnetic resonance imaging/real-time elastography fusion was 77.8% and 77.3% vs 74.1% and 62.9% for magnetic resonance imaging. CONCLUSIONS: Magnetic resonance imaging/transrectal ultrasound fusion enhances the likelihood of detecting clinically significant cancers in a repeat biopsy setting. Adding real-time elastography to magnetic resonance imaging supports the characterization of cancer suspicious lesions.