Objectives
To evaluate the agreement among readers with different expertise in detecting suspicious lesions at prostate multiparametric MRI using Prostate Imaging Reporting and Data System (PI-RADS) ...version 2.1.
Methods
We evaluated 200 consecutive biopsy-naïve or previously negative biopsy men who underwent MRI for clinically suspected prostate cancer (PCa) between May and September 2017. Of them, 132 patients underwent prostate biopsy. Seven radiologists (four dedicated uro-radiologists and three non-dedicated abdominal radiologists) reviewed and scored all MRI examinations according to PI-RADS v2.1. Agreement on index lesion detection was evaluated with Conger’s
k
coefficient, agreement coefficient 1 (AC1), percentage of agreement (PA), and indexes of specific positive and negative agreement. Clinical and radiological features that may influence variability were evaluated.
Results
Agreement in index lesion detection among all readers was substantial (AC1 0.738; 95% CI 0.695–0.782); dedicated radiologists showed higher agreement compared with non-dedicated readers. Clinical and radiological parameters that positively influenced agreement were PSA density ≥ 0.15 ng/mL/cc, pre-MRI high risk for PCa, positivity threshold of PI-RADS score 4 + 5, PZ lesions, homogeneous signal intensity of the PZ, and subjectively easy interpretation of MRI. Positive specific agreement was significantly higher among dedicated readers, up to 93.4% (95% CI 90.7–95.4) in patients harboring csPCa. Agreement on absence of lesions was excellent for both dedicated and non-dedicated readers (respectively 85.1% 95% CI 78.4–92.3 and 82.0% 95% CI 77.2–90.1).
Conclusions
Agreement on index lesion detection among radiologists of various experiences is substantial to excellent using PI-RADS v2.1. Concordance on absence of lesions is excellent across readers’ experience.
Key Points
• Agreement on index lesion detection among radiologists of various experiences is substantial to excellent using PI-RADS v2.1.
• Concordance between experienced readers is higher than between less-experienced readers.
• Concordance on absence of lesions is excellent across readers’ experience.
Background
Cardiac CT with late iodine enhancement (LIE-CT) may characterize the scarred myocardium, but the role of readers’ experience and scar pattern on LIE-CT diagnostic performance is unknown. ...Aim was to assess the diagnostic performance of LIE-CT according to readers’ experience, scar pattern and contrast-to-noise ratio (CNR) using late gadolinium enhancement MRI (LGE-MRI) as reference.
Methods
LIE-CT and LGE-MRI images of 40 consecutive patients were analyzed. Two readers with different experience (8 and 2 years) independently analyzed LIE-CT images defining the presence/absence of scar and scar CNR, segmental involvement, transmural pattern and scar etiology. The same parameters were extracted from LGE-MRI by two expert readers in consensus, blinded to the LIE-CT results.
Results
Scars were identified at LGE-MRI in 29/40 patients and 141/680 segments. Scar burden at LIE-CT versus LGE-MRI correlated better for the most experienced reader than for the least experienced one (
ρ
= 0.954 and
ρ
= 0.797,
p
< 0.001). The most experienced reader missed scars in 2 patients and in 21/141 segments; the least experienced in 5 patients and 53/141 segments. The most experienced reader showed higher accuracy and sensitivity compared to the least experienced in per-patient (accuracy: 95% vs. 88%; sensitivity: 93% vs. 83%) and per-segment analysis (accuracy: 96% vs. 92%; sensitivity: 85% vs. 62%). Specificity was excellent (100% per-patient, 99% per-segment,) regardless of readers’ experience. Missed scars had non-ischemic pattern, low scar burden (< 6%) and lower CNR compared to ischemic scars (2.33 vs. 3.54,
p
= 0.005).
Conclusion
LIE-CT represents an alternative to LGE-MRI, although the impact of readers’ experience on sensitivity for small non-ischemic scars should be considered.
The purpose of this study is to validate the accuracy of pelvic ultrasound (US) with the evaluation of uterine artery pulsatility index (PI) to exclude female precocious puberty.
Tanner breast ...development score, luteinizing hormone (LH) peak after gonadotropin-releasing hormone (GnRH) stimulation, and uterine and ovarian volumes and diameters were assessed with pelvic US in 495 girls at a single institution. The study population was divided as follows: prepubertal (
= 207), pubertal with physiologic activation of the hypothalamic-pituitary-ovarian axis (
= 176), and central precocious puberty (CPP;
= 112). PI was measured with spectral Doppler US at the ascending branches of the right uterine artery (50-Hz filter; time gain compensation, 73; pulse repetition frequency, 6.6). ROC analyses and
tests were performed.
The mean (± SD) PI values in the prepubertal, pubertal, and CPP groups were 6.3 ± 1.4, 3.4 ± 1.1, and 4.1 ± 1.5, respectively (
< 0.001). The best PI cutoff value to distinguish pubertal from prepubertal girls was 4.6 (sensitivity, 83%; specificity, 94%; positive predictive value, 95%; negative predictive value, 80%; accuracy, 87%). ROC AUC values for LH peak (cutoff value, 5 mU/mL) and for spectral Doppler US PI plus longitudinal uterine diameter (i.e., the combination of a PI of 4.6 with a longitudinal uterine diameter of 35 mm) were 0.9272 and 0.9439, respectively (
= 0.7925). The negative predictive values for LH peak and for PI plus longitudinal uterine diameter were 89% and 88%, respectively.
A PI greater than 4.6 at spectral Doppler US combined with a longitudinal uterine diameter less than 35 mm allows noninvasive exclusion of female precocious puberty with comparable accuracy and lower costs compared to examination of LH peak after GnRH stimulation. Therefore, PI plus longitudinal uterine diameter might be used as a noninvasive first-line test to exclude precocious puberty and thereby avoid further investigations.
: To prospectively compare clinical breast examination, mammography, ultrasonography, and contrast-enhanced magnetic resonance imaging (MRI) in a multicenter surveillance of high-risk women.
: We ...enrolled asymptomatic women aged ≥ 25: BRCA mutation carriers; first-degree relatives of BRCA mutation carriers, and women with strong family history of breast/ovarian cancer, including those with previous personal breast cancer.
: A total of 18 centers enrolled 501 women and performed 1592 rounds (3.2 rounds/woman). Forty-nine screen-detected and 3 interval cancers were diagnosed: 44 invasive, 8 ductal carcinoma in situ; only 4 pT2 stage; 32 G3 grade. Of 39 patients explored for nodal status, 28 (72%) were negative. Incidence per year-woman resulted 3.3% overall, 2.1% <50, and 5.4% ≥ 50 years (P < 0.001), 4.3% in women with previous personal breast cancer and 2.5% in those without (P = 0.045). MRI was more sensitive (91%) than clinical breast examination (18%), mammography (50%), ultrasonography (52%), or mammography plus ultrasonography (63%) (P < 0.001). Specificity ranged 96% to 99%, positive predictive value 53% to 71%, positive likelihood ratio 24 to 52 (P not significant). MRI showed significantly better negative predictive value (99.6) and negative likelihood ratio (0.09) than those of the other modalities. At receiver operating characteristic analysis, the area under the curve of MRI (0.97) was significantly higher than that of mammography (0.83) or ultrasonography (0.82) and not significantly increased when MRI was combined with mammography and/or ultrasonography. Of 52 cancers, 16 (31%) were diagnosed only by MRI, 8 of 21 (38%) in women <50, and 8 of 31 (26%) in women ≥ 50 years of age.
: MRI largely outperformed mammography, ultrasonography, and their combination for screening high-risk women below and over 50.
The mechanics of blood flow in arteries plays a key role in the health of individuals. In this framework, the role played by the presence of helical flow in the human aorta is still not clear in its ...relation to physiology and pathology. We report here a method for quantifying helical flow in vivo employing time-resolved cine phase contrast magnetic resonance imaging to obtain the complete spatio-temporal description of the three-dimensional pulsatile blood flow patterns in aorta. The method is applied to data of one healthy volunteer. Particle traces were calculated from velocity data: to them we applied a Lagrangian-based method for helical flow quantification, the Helical Flow Index, which has been developed and evaluated in silico in order to reveal global organization of blood flow. Our results: (i) put in evidence that the systolic hemodynamics in aorta is characterized by an evolving helical flow (we quantified a 24% difference in terms of the content of helicity in the streaming blood, between mid and early systole); (ii) indicate that in the first part of the systole helicity is ascrivable mainly to the asymmetry of blood flow in the left ventricle, joined with the laterality of the aorta. In conclusion, this study shows that the quantification of helical blood flow in vivo is feasible, and it might allow detection of anomalies in the expected physiological development of helical flow in aorta and accordingly, could be used in a diagnostic/prognostic index for clinical practice.
Background
The aim of this study was to prospectively compare the diagnostic performance of magnetic resonance imaging (MRI), multidetector computed tomography (MDCT) and endoscopic ultrasonography ...(EUS) in the preoperative locoregional staging of gastric cancer.
Methods
This study had Institutional Review Board approval, and informed consent was obtained from all patients. Fifty-two patients with biopsy-proven gastric cancer underwent preoperative 1.5-T MRI, 64-channel MDCT and EUS. All images were analysed blind, and the results were compared with histopathological findings according to the seventh edition of the TNM classification. After the population had been divided on the basis of the local invasion (T1-3 vs T4a-b) and nodal involvement (N0 vs N+), sensitivity, specificity, positive and negative predictive value, and accuracy were calculated and diagnostic performance measures were assessed using the McNemar test.
Results
For T staging, EUS showed higher sensitivity (94 %) than MDCT and MRI (65 and 76 %;
p
= 0.02 and
p
= 0.08). MDCT and MRI had significantly higher specificity (91 and 89 %) than EUS (60 %) (
p
= 0.0009 and
p
= 0.003). Adding MRI to MDCT or EUS did not result in significant differences for sensitivity. For N staging, EUS showed higher sensitivity (92 %) than MRI and MDCT (69 and 73 %;
p
= 0.01 and
p
= 0.02). MDCT showed better specificity (81 %) than EUS and MRI (58 and 73 %;
p
= 0.03 and
p
= 0.15).
Conclusions
Our prospective study confirmed the leading role of EUS and MDCT in the staging of gastric cancer and did not prove, at present, the value of the clinical use of MRI.
Fabry's disease may be difficult to differentiate from symmetric hypertrophic cardiomyopathy. Our aim was to compare the myocardial location and distribution patterns of delayed enhancement between ...patients with Fabry's disease who are affected by symmetric myocardial hypertrophy and patients with symmetric hypertrophic cardiomyopathy in order to identify a specific sign to best differentiate the two diseases.
Patients with Fabry's disease-related hypertrophy showed left ventricular (LV) delayed enhancement with a typical and consistently found pattern characterized by the involvement of the inferolateral basal or mid basal segments and a mesocardial distribution that spared the subendocardium. This pattern seems to be specific to Fabry's disease; in fact, patients with symmetric hypertrophic cardiomyopathy had variable locations and distributions of delayed enhancement. These observations may contribute to identifying Fabry's disease as a specific cause of symmetric hypertrophy.
To compare the diagnostic performance of MR and diffusion-weighted imaging (DWI), multidetector CT, endoscopic ultrasonography (EUS) and
F-FDG (fluorine-18 fludeoxyglucose) positron emission ...tomography CT (PET-CT) in the pre-operative locoregional staging of oesophageal cancer.
18 patients with oesophageal or Siewert I tumour (9 directly treated with surgery and 9 addressed to chemo-/radiotherapy before) underwent 1.5-T MR and DWI, 64-channel multidetector CT, EUS and PET-CT before (n = 18) and also after neoadjuvant treatment (n = 9). All images were analysed and staged blindly by dedicated operators (seventh TNM edition). Two radiologists calculated independently the apparent diffusion coefficient from the first scan. Results were compared with histopathological findings. After the population had been divided according to local invasion (T1-T2 vs T3-T4) and nodal involvement (N0 vs N+), sensitivity, specificity, accuracy, positive- and negative-predictive values were calculated and compared. Quantitative measurements from DWI and PET-CT were also analysed.
For T staging, EUS showed the best sensitivity (100%), whereas MR showed the highest specificity (92%) and accuracy (83%). For N staging, MR and EUS showed the highest sensitivity (100%), but none of the techniques showed adequate results for specificity. Overall, MR showed the highest accuracy (66%) for N stage, although this was not significantly different to the other modalities. The apparent diffusion coefficient was different between surgery-only and chemo-/radiotherapy groups (1.90 vs 1.30 × 10
mm
s
, respectively; p = 0.005)-optimal cut off for local invasion: 1.33 × 10
mm
s
(p = 0.05). Difference in standardized uptake value was also very close to conventional levels of statistical significance (8.81 vs 13.97 g cm
, respectively; p = 0.05)-optimal cut off: 7.97 g cm
(p = 0.44).
In this pilot study, we have shown that MR with DWI could enrich the current pre-operative work-up for oesophageal cancer and could be used for T and N staging. However, larger studies will need to be carried out before introducing this technique in the standard diagnostic pathway, in order to understand if MR with DWI could change its management and replace more costly or invasive tests such as PET-CT or EUS. Advances in knowledge: This pilot study represents the first effort where the four techniques have been prospectively compared together for oesophageal cancer staging. The combination of MR and DWI could provide important, additional information for staging and initial treatment decision-making.
Objectives
To investigate the association between preoperative texture analysis from multidetector computed tomography (MDCT) and overall survival in patients with gastric cancer.
Methods
...Institutional review board approval and informed consent were obtained. Fifty-six patients with biopsy-proved gastric cancer were examined by MDCT and treated with surgery. Image features from texture analysis were quantified, with and without filters for fine to coarse textures. The association with survival time was assessed using Kaplan–Meier and Cox analysis.
Results
The following parameters were significantly associated with a negative prognosis, according to different thresholds:
energy
no filter – Logarithm of relative risk (Log RR): 3.25;
p
= 0.046;
entropy
no filter (Log RR: 5.96;
p
= 0.002);
entropy
filter 1.5 (Log RR: 3.54;
p
= 0.027);
maximum Hounsfield unit value
filter 1.5 (Log RR: 3.44;
p
= 0.027);
skewness
filter 2 (Log RR: 5.83;
p
= 0.004);
root mean square
filter 1 (Log RR: - 2.66;
p
= 0.024) and
mean absolute deviation
filter 2 (Log RR: - 4.22;
p
= 0.007).
Conclusions
Texture analysis could increase the performance of a multivariate prognostic model for risk stratification in gastric cancer. Further evaluations are warranted to clarify the clinical role of texture analysis from MDCT.
Key points
•
Textural analysis from computed tomography can be applied in gastric cancer
.
•
Preoperative non
-
invasive texture features are related to prognosis in gastric cancer
.
•
Texture analysis could help to evaluate the aggressiveness of this tumour
.
Skeletal muscle remodeling in response to various noxae physiologically includes structural changes and inflammatory events. The possibility to study those phenomena in-vivo has been hampered by the ...lack of validated imaging tools. In our study, we have relied on multiparametric magnetic resonance imaging for quantitative monitoring of muscle changes in mice experiencing age-related sarcopenia or active regeneration after sterile acute injury of tibialis anterior muscle induced by cardiotoxin (CTX) injection. The extent of myofibrils' necrosis, leukocyte infiltration, and regeneration have been evaluated and compared with parameters from magnetic resonance imaging: T2-mapping (T2 relaxation time; T2-rt), diffusion-tensor imaging (fractional anisotropy, F.A.) and diffusion weighted imaging (apparent diffusion coefficient, ADC). Inflammatory leukocytes within the perimysium and heterogeneous size of fibers characterized aged muscles. They displayed significantly increased T2-rt (P<0.05) and F.A. (P<0.05) compared with young muscles. After acute damage T2-rt increased in otherwise healthy young muscles with a peak at day 3, followed by a progressive decrease to basal values. F.A. dropped 24 hours after injury and afterward increased above the basal level in the regenerated muscle (from day 7 to day 15) returning to the basal value at the end of the follow up period. The ADC displayed opposite kinetics. T2-rt positively correlated with the number of infiltrating leucocytes retrieved by immunomagnetic bead sorting from the tissue (r = 0.92) and with the damage/infiltration score (r = 0.88) while F.A. correlated with the extent of tissue regeneration evaluated at various time points after injury (r = 0.88). Our results indicate that multiparametric MRI is a sensitive and informative tool for monitoring inflammatory and structural muscle changes in living experimental animals; particularly, it allows identifying the increase of T2-rt and F.A. as common events reflecting inflammatory infiltration and muscle regeneration in the transient response of the tissue to acute injury and in the persistent adaptation to aging.
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