Diagnosis of postoperative recurrence of Crohn disease with MR-enterography: Value of diffusion-weighted imaging

PurposeTo compare the diagnostic capabilities of MR enterography (MRE) using contrast-enhanced (CE) sequences with those of MRE using diffusion-weighted (DW) imaging for the diagnosis of postoperative recurrence at the neo-terminal ileum and/or anastomosis after ileocolonic resection in patients with Crohn disease (CD), and to clarify the role of additional DW imaging to CE-MRE in this context.Material and methodsForty patients who underwent ileal resection for CD, and both endoscopy and MRE within the first year after surgery were included. There were 21 men and 19 women, with a mean age of 38 years ± 12 (SD) years (range: 18–67 years). MRE examinations were blindly analyzed independently by one senior (R1) and one junior (R2) radiologist for the presence of small bowel postoperative recurrence at the anastomotic site. During a first reading session, T2-, steady-state- and DW-MRE were reviewed (DW-MRE or set 1). During a separate distant session, T2-, steady-state- and CE-MRE were reviewed (CE-MRE or set 2). Lastly, all sequences were analyzed altogether (set 3). Performances of each reader for the diagnosis of postoperative recurrence were evaluated using endoscopic findings as the standard of reference (Rutgeerts score ≥ i2b).ResultsFifteen patients out of 40 (37.5%) had endoscopic postoperative recurrence at the anastomotic site. Sensitivity for the diagnosis of postoperative recurrence was 73% (95% CI: 51–96%) for R1 and 67% (95% CI: 43–91%) for R2 using set 1, and 80% (95% CI: 60–100%) for both readers using set 2. There was no significant differences in sensitivity between reading set 1 and reading set 2, for either R1 or R2 (R1, P  > 0.99; R2, P = 0.48). Specificity was 96% (95% CI: 88–100%) for both readers using set 1 or using set 2. Reading set 3 yielded an area under the ROC curve (AUC) of 0.93 (95% CI: 0.84–1) versus 0.89 (95% CI: 0.75–1) with set 1 (P = 0.18) and versus 0.89 (95% CI: 0.78–1) with set 2 (P = 0.21). No significant differences in AUC were found between set 1 or 2 and set 3 (P = 0.18), nor between set 1 and 2 (P = 0.76). Accuracies were 88% (95% CI: 74–95%) and 85% (95% CI: 71–93%) for DW-MRE for R1 and R2, respectively; 90% (95% CI: 77–96%) for CE-MRE for both readers; and 93% (95% CI: 80–97%) and 88% (95% CI: 74–95%) for R1 and R2 with set 3, respectively.ConclusionDW-MRE has diagnostic capabilities similar to those of CE-MRE for the diagnosis of postoperative recurrence of CD at the anastomotic site.     

Arterial endofibrosis in endurance athletes: Prospective comparison of the diagnostic accuracy of intra-arterial digital subtraction angiography and computed tomography angiography

PurposeTo prospectively compare the diagnostic capabilities of computed tomography angiography (CTA) to those of digital subtraction angiography (DSA) in endurance athletes with suspicion of arterial endofibrosis.Materials and methodsForty-five athletes (39 men, 6 women; median age: 30 years, interquartile range: 23–42 years) prospectively underwent DSA and CTA without (n = 5) or with (n = 40) electrocardiogram gating. DSA was interpreted by a single expert (experience of 15 years). CTA was independently interpreted by three other readers (experience of 5–8 years). Readers assessed the presence and degree of stenoses on iliac and femoral arteries and the overall diagnosis (negative, uncertain, positive) of endofibrosis at the limb level. Sensitivities and specificities of DSA and CTA were estimated at the limb level using histological findings and long-term follow-up as reference, and compared using the McNemar test.ResultsFor diagnosing and quantifying stenoses, concordance between DSA and CTA was moderate-to-good for common and external iliac arteries, moderate for lateral circumflex arteries and poor-to-moderate for the other branches of the deep femoral artery. It was good for all readers for the overall diagnosis of endofibrosis. After long-term follow-up (median, 95 months; interquartile range: 7–109 months), DSA sensitivity and specificity were respectively 88.6% (39/44; 95% confidence interval [CI]: 76–95%) and 75% (24/32; 95% CI: 57.9–86.7%); CTA sensitivity and specificity were respectively 88.6% (39/44; 95% CI: 76–95%; P > 0.99) and 84.4% (27/32; 95% CI: 68.2–93.1%; P = 0.51), 86.3% (38/44; 95% CI: 73.3–93.6%; P > 0.99) and 75% (24/32; 95% CI: 57.9–86.7%; P > 0.99), and 84.1% (37/44; 95% CI: 70.6–92.1%; P = 0.68) and 75% (24/32; 95% CI: 57.9–86.7%; P > 0.99) for the three readers.ConclusionCTA shows performances similar to those of DSA in predicting the long-term diagnosis of endofibrosis in endurance athletes with suggestive symptoms.     

Safety and oncologic efficacy of percutaneous MRI-guided cryoablation of intraparenchymal renal cancers

PurposeThe purpose of this study was to evaluate the safety and oncologic efficacy of percutaneous magnetic resonance imaging (MRI)-guided cryoablation of intraparenchymal renal cancer.Materials and methodsBetween February 2009 and August 2019, 31 consecutives patients with 31 entirely intraparenchymal biopsy-proven renal cancers were treated with cryoablation under MRI-guidance in our institution, and were retrospectively included. There were 20 men and 11 women with a mean age of 68.5 ± 12.5 (SD) (range: 40–91 years). Patient, tumor- and procedure-related, and follow-up data were retrospectively collected and analyzed. Local recurrence free (LRFS), metastasis free (MFS), disease free (DFS), cancer specific (CSS), and overall survivals (OS) were calculated.ResultsPrimary and secondary technical efficacy rates were 94% and 100%, respectively. Median follow-up was 27 months. Seven (7/31; 23%) minor complications were noted in 7 patients. Patients showed a significant decline of the estimated glomerular filtration rate (eGFR) between baseline and nadir (mean basal eGFR 65.9 ± 22.4 [SD] mL/min/1.73 m² vs. mean nadir eGFR 52.8 ± 26.0 [SD] mL/min/1.73 m²; P < 0.001), but only two showed a clinically significant renal function decline. Three-year estimates of primary and secondary LRFS, MFS, and DFS were 64% (95% confidence interval [CI]: 47–87%), 89% (95% CI: 78–99%), 83% (95% CI: 77–98%), and 45% (95% CI: 28–73%), respectively. No patients died due to renal cancer evolution (three-year CSS of 100%; 95% CI: 100–100%). One patient died 52 months after the percutaneous treatment due to cryoablation-unrelated causes (three-year OS of 100%; 95% CI: 100–100%).ConclusionMRI-guided percutaneous cryoablation for intraparenchymal renal cancer offers good oncologic outcomes with acceptable complication rates and renal function worsening.     

Prediction of overall survival in patients with hepatocellular carcinoma treated with Y-90 radioembolization by imaging response criteria

PurposeTo evaluate the potential of imaging criteria in predicting overall survival of patients with hepatocellular carcinoma (HCC) after a first transcatheter arterial yttrium-90 radioembolization (TARE)Materials and methodsFrom October 2013 to July 2017, 37 patients with HCC were retrospectively included. There were 34 men and 3 women with a mean age of 60.5 ± 10.2 (SD) years (range: 32.7–78.9 years). Twenty-five patients (68%) were Barcelona Clinic Liver Cancer (BCLC) C and 12 (32%) were BCLC B. Twenty-four primary index tumors (65%) were > 5 cm. Three radiologists evaluated tumor response on pre- and 4–7 months post-TARE magnetic resonance imaging or computed tomography examinations, using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, modified RECIST (mRECIST), European Association for Study of the Liver (EASL), volumetric RECIST (vRECIST), quantitative EASL (qEASL) and the Liver Imaging Reporting and Data System treatment response algorithm. Kaplan–Meier survival curves were used to compare responders and non-responders for each criterion. Univariate and multivariate Cox proportional hazard ratio (HR) analysis were used to identify covariates associated with overall survival. Fleiss kappa test was used to assess interobserver agreement.ResultsAt multivariate analysis, RECIST 1.1 (HR: 0.26; 95% confidence interval [95% CI]: 0.09–0.75; P = 0.01), mRECIST (HR: 0.22; 95% CI: 0.08–0.59; P = 0.003), EASL (HR: 0.22; 95% CI: 0.07–0.63; P = 0.005), and qEASL (HR: 0.30; 95% CI: 0.12–0.80; P = 0.02) showed a significant difference in overall survival between responders and nonresponders. RECIST 1.1 had the highest interobserver reproducibility.ConclusionRECIST and mRECIST seem to be the best compromise between reproducibility and ability to predict overall survival in patients with HCC treated with TARE.     

Ultrasonographic anatomy of the long thoracic nerve: A reappraisal using high frequency (24-MHz) probe

PurposeThe purpose of this study was to analyze the potential of ultrasound with a high frequency probe (24-MHz) in the assessment of the long thoracic nerve (LTN) and describe ultrasonographic landmarks that can be used for standardization.Material and methodsUltrasonography analysis of the LTN was done on 2 LTNs in a cadaver specimen and then on 30 LTNs in 15 healthy volunteers (12 men, 3 women; mean age, 28.8 ± 3.8 [SD] years; age range: 24–39 years) by two independent radiologists (R1 and R2) using a 24-MHz probe. Interrater agreement was assessed using Kappa test (K) and intraclass correlation coefficient (ICC).ResultsIn the cadaver, dissection confirmed that the India ink was injected near the LTN in the middle scalene muscle. In volunteers, visibility of the LTN above the clavicle was highly reproducible for the branches arising from C5 (R1: 87% [26/30]; R2: 90% [27/30]; K = 0.83) and from C6 (R1: 100% [30/30]; R2: 97% [29/30]; K = 0.94). Where the nerve emerged from the middle scalene muscle, the mean diameter was 0.85 ± 0.24 (SD) mm (range: 0.4–1.6 mm) for R1 and 0.9 ± 0.23 (SD) mm (range: 0.4–1.7 mm) for R2 (ICC: 0.96; 95% CI: 0.92–0.98%). Along the thoracic wall, where LTN run along the lateral thoracic artery, the mean diameter was 0.83 ± 0.19 (SD) mm (range: 0.5–1.27 mm) for R1 and 0.89 ± 0.21 (SD) mm (range: 0.6–1.2 mm) for R2 (ICC: 0.86; 95% CI: 0.72–0.93%).ConclusionThe LTN can be analyzed with ultrasound using high-frequency probe by using the C5 and C6 roots, the middle scalene muscle above the clavicle and the lateral thoracic artery on the chest wall as landmarks.     

Candidates to salvage therapy after external-beam radiotherapy of prostate cancer: Predictors of local recurrence volume and metastasis-free survival

PurposeThe purpose of this study was to assess the predictors of metastasis-free survival (MFS) and of the volume of the local recurrence in patients with rising prostate-specific antigen (PSA) serum level after radiotherapy for prostate cancer and referred for prostate magnetic resonance imaging (MRI) and biopsy in view of salvage treatment.Materials and methodsA total of 132 consecutive men (median age, 70 years; IQR, 66–77 years) with rising PSA after prostate radiotherapy who underwent prostate MRI and biopsy in view of salvage treatment between January 2010 and July 2017 were retrospectively evaluated at a single center. MFS predictors were assessed with Cox models. Predictors of the volume of the local recurrence (number of invaded prostate sectors at biopsy) were assessed using Poisson regression among variables available at PSA relapse.ResultsAt multivariate analysis, an initial Gleason score ≥ 8 (OR = 7 [95% confidence interval (CI): 1.2–40]; P = 0.03), a recent radiotherapy (OR = 17 [95% CI: 3.9–72]; P < 0.0001), the use of androgen deprivation therapy at PSA relapse (OR = 12.5 [95% CI: 2.8–57]; P = 0.001) and the number of invaded prostate sectors (OR = 1.5 [95% CI: 1.1–2]; P = 0.007) and maximum cancer core length (OR = 0.7 [95%CI: 0.6–0.9]; P = 0.002) at biopsy performed at PSA relapse were significant MFS predictors. The PSA level at relapse was significant independent predictor of the volume of local recurrence only when used as a continuous variable (P = 0.0002) but not when dichotomized using the nadir + 2 threshold (P = 0.41).ConclusionPathological and clinical factors can help predict MFS in patients with rising PSA after prostate radiotherapy and candidates to salvage treatment. The PSA level at relapse has strong influence on the local recurrence volume when used as a continuous variable.     

Reproducibility of LI-RADS treatment response algorithm for hepatocellular carcinoma after locoregional therapy

PurposeTo determine inter-reader agreement in categorizing hepatocellular carcinoma (HCC) treated with locoregional therapy using the Liver Imaging Reporting and Data System (LI-RADS) treatment response (LR-TR) algorithm.Materials and methodsA total of 93 patients with a total of 112 HCC nodules that were treated using thermal ablation or transarterial chemoembolization were prospectively included. There were 79 men and 14 women with a mean age of 55 ± 2.6 (SD) years (range: 48–63 years). All patients underwent magnetic resonance imaging (MRI) examination of the liver and MR images were analyzed by two independent observers. Treated HCC nodules were categorized into four groups according to LR-TR scoring system including: (i) LR-TR non-evaluable (treated, response not evaluable); (ii) LR-TR nonviable (treated, probably or definitively not viable); (iii) LR-TR equivocal (treated, equivocally viable) and (iv) LR-TR viable (treated, probably or definitively viable). The inter-observer agreement in LR-TR categorization was assessed using the kappa statistics.ResultsThere was excellent inter-observer agreement between the two reviewers for overall treated HCC according to LR-TR algorithm (kappa = 0.938; 95% CI: 0.89–1.00; P = 0.001) with 97.31% agreement. The LR-TR categories by both reviewers were non-viable (77/112; 69.6% and 76/112; 67.9%), viable (30/112; 26.8% and 32/112; 27.7%) and equivocal (5/112; 4.4% and 4/112; 3.6%). There was excellent inter-observer agreement for LR-TR nonviable (kappa = 0.938; 95% CI: 0.87–1.0; P = 0.001) with 97.3% agreement, LR-TR viable (kappa = 0.955; 95% CI: 0.89–1.00; P = 0.001) with 98.2% agreement and good inter-observer agreement for LR-TR equivocal (kappa = 0.700; 95% CI: 0.28–1.0; P = 0.001) with 97.3% agreement.ConclusionLR-TR algorithm conveys high degrees of inter-observer agreement for the evaluation of treatment response of HCC after thermal ablation and transarterial chemoembolization.     

Bladder endometriosis: Preoperative MRI analysis with assessment of extension to ureteral orifices

PurposeThe purpose of this study was to retrospectively evaluate the performance of magnetic resonance imaging (MRI) in locating endometriosis implants within the bladder wall with assessment of ureteral orifice extension using surgical findings as standard of reference.Materials and methodsMRI examinations of 39 consecutive women (mean age: 31.2 ± 5.5 [SD] years; age range: 22–42 years) operated in 3 university hospitals for bladder endometriosis over a 6-year period were reviewed by 2 independent readers. Interobserver agreement was assessed using Kappa tests. Results of consensus reading were used to calculate sensitivity, specificity and accuracy of MRI for the diagnosis, location and extent of endometriosis implants using surgical findings as the standard of reference.ResultsMean bladder repletion volume was 134 ± 110 [SD] mL (range: 21–479 mL). The mean largest endometriosis implant diameter was 30 ± 7 [SD] mm (range: 19–41 mm). On MR images, 34/39 (87%) endometriosis implants were present in the two anterior thirds of the dome (k = 0.45), 31/39 (79%) extended or were present in the posterior third pouch (k = 0.92) and 25/39 (64%) extended into the bladder base (k = 0.84) with sensitivities of 100% (31/31; 95% confidence interval [CI]: 89–100%), 100% (30/30; 95% CI: 88–100%) and 90% (19/21; 95% CI: 69–98%), respectively, specificities of 83% (5/6, 95% CI: 36–100), 88% (7/8, 95% CI: 47–100%), 87% (13/15; 95% CI: 52–96), respectively and accuracies of 97% (36/37, 95% CI: 86–100%), 97% (37/38; 95% CI: 86–100%), and 89% (32/36; 95% CI: 74–97%), respectively. In 9 (9/25; 36%) patients with bladder base involvement, a zero distance was reported between endometriosis implants and ureteral orifices, all but one presenting with low-to-moderate bladder volumes. In the two patients who needed ureteral resection-reimplantation, ureteral dilation was associated with a zero distance. External adenomyosis was reported in 26/39 (66%) patients (k = 0.94).ConclusionA dedicated preoperative MRI work-up for bladder endometriosis helps accurately depict and locate endometriosis implants. Adequate bladder filling is needed to improve appropriate estimate of the distance between endometriosis implants and ureteral orifices to better predict requirement of ureteral resection-reimplantation.     

Texture analysis of apparent diffusion coefficient (ADC) map for glioma grading: Analysis of whole tumoral and peri-tumoral tissue

PurposeTo prospectively investigate the capabilities of texture analysis (TA) based on apparent diffusion coefficient (ADC) map of the entire tumor volume and the whole volume of peri-tumoral edema, in discriminating between high-grade glioma (HGG) and low-grade glioma (LGG).Materials and methodsA total of 33 patients with histopathological proven glioma were prospectively included. There were 20 men and 13 women with a mean age of 54.5 ± 14.7 (standard deviation [SD]) years (range: 34–75 years). TA parameters of whole tumor and peri-tumoral edema were extracted from the ADC map obtained with diffusion-weighted spin-echo echo-planar magnetic resonance imaging at 1.5–T. TA variables of HGG were compared to those of LGG. The optimum cut-off values of TA variables and their corresponding sensitivity, specificity and accuracy for differentiating between LGG and HGG were calculated using receiver operating characteristic curve analysis.ResultsMean and median tumoral ADC of HGG were significantly lower than those of LGG, at 1.23 × 10^?3 mm²/s and 1.21 × 10^?3 mm²/s cut-off values, yielding 70% sensitivity each (95% CI: 59–82% and 61–80%, respectively), 80% (95% CI: 79–98%) and 90% (95% CI: 82–97%) specificity, and 73% (95% CI: 66–91%) and 76% (95% CI: 72–90%) accuracy, respectively. Significant differences in tumoral and peri-tumoral kurtosis were found between HGG and LGG at 1.60 and 0.314 cut-off values yielding sensitivities of 74% (95% CI: 58–83%) and 70% (95% CI: 59–84%), specificities of 90% (95% CI: 80–95%) and 70% (95% CI: 64–83%) and accuracies of 79% (95% CI: 69–89%) and 70% (95% CI: 64–77%), respectively.ConclusionMeasurements of whole tumoral and peri-tumoral TA, based on ADC maps, provide useful information that helps distinguish between HGG and LGG.     

Differentiation between Fabry disease and hypertrophic cardiomyopathy with cardiac T1 mapping

PurposeTo evaluate the potential of non-contrast myocardial T1 mapping on cardiovascular magnetic resonance examination (CMR) in differentiating patients with Fabry disease (FD) from those with hypertrophic cardiomyopathy (HCM) and healthy control subjects.Materials and methodsSeventeen patients with FD (8 men, 9 women; mean age, 48  ± 18 [SD] years; [range: 19–73 years]; 53% with left ventricular hypertrophy [LVH]) were matched with 36 patients with hypertrophic cardiomyopathy (HCM) (22 men, 14 women; mean age, 57 ± 16 [SD] years; [range: 22–85 years]) and 70 healthy control subjects (34 men, 36 women; mean age, 38 ± 15 [SD] years; [range: 18–65 years]). Cardiac T1 mapping was performed using the modified Look-Locker inversion (MOLLI®) sequence on a 1.5-T magnet. T1 values were calculated, on midventricular section, for septal left ventricular segments (S8–S9) and all mid-ventricular ones (global T1 values; S7–S12). Statistical analysis included unpaired Mann-Whitney test, receiver operating characteristic curve and likelihood ratios.ResultsSeptal native T1 values were significantly decreased in patients with FD (889 ± 61 [SD] ms; range: 784–980 ms) compared to those with HCM (995 ± 48 [SD] ms; range: 935–1125 ms) (P < 0.001) and versus healthy controls (965 ± 29 [SD] ms; range: 910–1028 ms) (P < 0.001). Global native T1 values were also significantly decreased in patients with FD (891 ± 49 [SD] ms; range 794–970 ms) compared to those with HCM (995 ± 34 [SD] ms; range: 952–1086 ms) (P < 0.001) and versus healthy controls (966 ± 27 [SD] ms; range: 920–1042 ms) (P < 0.001). A septal left ventricular native T1 cutoff value of 940 ms could distinguish FD from HCM with 88% sensitivity (95% CI: 73–100%) and 92% specificity (95% CI: 83–100%). Positive likelihood ratio was 11, negative likelihood ratio was 0.12. Compared to controls, the same threshold could distinguish FD with 88% sensitivity (95% CI: 73–100%) and 86% specificity (95% CI: 78–94%). Positive likelihood ratio was 6.3, negative likelihood ratio was 0.14. T1 value was abnormal in 4 of 8 (50%) of FD patients who did not have LVH.ConclusionNative T1 values are significantly lower in patients with FD by comparison with those with HCM and healthy volunteers.     

MRI-based traditional radiomics and computer-vision nomogram for predicting lymphovascular space invasion in endometrial carcinoma

PurposeTo determine the capabilities of MRI-based traditional radiomics and computer-vision (CV) nomogram for predicting lymphovascular space invasion (LVSI) in patients with endometrial carcinoma (EC).Materials and methodsA total of 184 women (mean age, 52.9 ± 9.0 [SD] years; range, 28–82 years) with EC were retrospectively included. Traditional radiomics features and CV features were extracted from preoperative T2-weighted and dynamic contrast-enhanced MR images. Two models (Model 1, the radiomics model; Model 2, adding CV radiomics signature into the Model 1) were built. The performance of the models was evaluated by the area under the curve (AUC) of the receiver operator characteristic (ROC) in the training and test cohorts. A nomogram based on clinicopathological metrics and radiomics signatures was developed. The predictive performance of the nomogram was assessed by AUC of the ROC in the training and test cohorts.ResultsFor predicting LVSI, the AUC values of Model 1 in the training and test cohorts were 0.79 (95% confidence interval [CI]: 0.702–0.889; accuracy: 65.9%; sensitivity: 88.8%; specificity: 57.8%) and 0.75 (95% CI: 0.585–0.914; accuracy: 69.5%; sensitivity: 85.7%; specificity: 62.5%), respectively. The AUC values of Model 2 in the training and test cohorts were 0.93 (95% CI: 0.875–0.991; accuracy: 94.9%; sensitivity: 91.6%; specificity: 96.0%) and 0.81 (95% CI: 0.666–0.962; accuracy: 71.7%; sensitivity: 92.8%; specificity: 62.5%), respectively. The discriminative ability of Model 2 was significantly improved compared to Model 1 (Net Reclassification Improvement [NRI] = 0.21; P = 0.04). Based on histologic grade, FIGO stage, Rad-score and CV-score, AUC values of the nomogram to predict LVSI in the training and test cohorts were 0.98 (95% CI: 0.955–1; accuracy: 91.6%; sensitivity: 91.6%; specificity: 96.0%) and 0.92 (95% CI: 0.823–1; accuracy: 91.3%; sensitivity: 78.5%; specificity: 96.8%), respectively.ConclusionsMRI-based traditional radiomics and computer-vision nomogram are useful for preoperative risk stratification in patients with EC and may facilitate better clinical decision-making.     

Diagnostic performance of ultra-low dose versus standard dose CT for non-traumatic abdominal emergencies

PurposeThe purpose of this study was to compare the diagnostic performance of ultra-low dose (ULD) to that of standard (STD) computed tomography (CT) for the diagnosis of non-traumatic abdominal emergencies using clinical follow-up as reference standard.Materials and methodsAll consecutive patients requiring emergency abdomen-pelvic CT examination from March 2017 to September 2017 were prospectively included. ULD and STD CTs were acquired after intravenous administration iodinated contrast medium (portal phase). CT acquisitions were performed at 125 mAs for STD and 55 mAs for ULD. Diagnostic performance was retrospectively evaluated on ULD and STD CTs using clinical follow-up as a reference diagnosis.ResultsA total of 308 CT examinations from 308 patients (145 men; mean age 59.1 ± 20.7 (SD) years; age range: 18–96 years) were included; among which 241/308 (78.2%) showed abnormal findings. The effective dose was significantly lower with the ULD protocol (1.55 ± 1.03 [SD] mSv) than with the STD (3.67 ± 2.56 [SD] mSv) (P < 0.001). Sensitivity was significantly lower for the ULD protocol (85.5% [95%CI: 80.4–89.4]) than for the STD (93.4% [95%CI: 89.4–95.9], P < 0.001) whereas specificities were similar (94.0% [95%CI: 85.1–98.0] vs. 95.5% [95%CI: 87.0–98.9], respectively). ULD sensitivity was equivalent to STD for bowel obstruction and colitis/diverticulitis (96.4% [95%CI: 87.0–99.6] and 86.5% [95%CI: 74.3–93.5] for ULD vs. 96.4% [95%CI: 87.0–99.6] and 88.5% [95%CI: 76.5–94.9] for STD, respectively) but lower for appendicitis, pyelonephritis, abscesses and renal colic (75.0% [95%CI: 57.6–86.9]; 77.3% [95%CI: 56.0–90.1]; 90.5% [95%CI: 69.6–98.4] and 85% [95%CI: 62.9–95.4] for ULD vs. 93.8% [95%CI: 78.6–99.2]; 95.5% [95%CI: 76.2–100.0]; 100.0% [95%CI: 81.4–100.0] and 100.0% [95%CI: 80.6–100.0] for STD, respectively). Sensitivities were significantly different between the two protocols only for appendicitis (P = 0.041).ConclusionIn an emergency context, for patients with non-traumatic abdominal emergencies, ULD-CT showed inferior diagnostic performance compared to STD-CT for most abdominal conditions except for bowel obstruction and colitis/diverticulitis detection.     

Head-to-head comparison of lung perfusion with dual-energy CT and SPECT-CT

PurposeTo compare the quantitative and qualitative lung perfusion data acquired with dual energy CT (DECT) to that acquired with a large field-of-view cadmium-zinc-telluride camera single-photon emission CT coupled to a CT system (SPECT-CT).Materials and methodsA total of 53 patients who underwent both dual-layer DECT angiography and perfusion SPECT-CT for pulmonary hypertension or pre-operative lobar resection surgery were retrospectively included. There were 30 men and 23 women with a mean age of 65.4 ± 17.5 (SD) years (range: 18–88 years). Relative lobar perfusion was calculated by dividing the amount (of radiotracer or iodinated contrast agent) per lobe by the total amount in both lungs. Linear regression, Bland-Altman analysis, and Pearson's correlation coefficient were also calculated. Kappa test was used to test agreements in morphology and severity of perfusion defects assessed on SPECT-CT and on DECT iodine maps with a one-month interval. Wilcoxon rank sum test was used to compare the sharpness of perfusion defects and radiation dose among modalities.ResultsStrong correlations for relative lobar perfusion using linear regression analysis and Pearson's correlation coefficient (r = 0.93) were found. Bland-Altman analysis revealed a −0.10 bias, with limits of agreement between [−6.01; 5.81]. With respect to SPECT- CT as standard of reference, the sensitivity, specificity, PPV, NPV, accuracy for lobar perfusion defects were 89.4% (95% CI: 82.6−93.4%), 96.5% (95% CI: 92.1−98.5%), 95.6% (95% CI: 90.9−97.8%), 91.4% (95% CI: 85.6−94.9%) and 93.0% (95% CI: 87.6−96.1%) respectively. High level of agreement was found for morphology and severity of perfusion defects between modalities (Kappa = 0.84 and 0.86 respectively) and on DECT images among readers (Kappa = 0.94 and 0.89 respectively). A significantly sharper delineation of perfusion defects was found on DECT images (P < 0.0001) using a significantly lower equivalent dose of 4.1 ± 2.3 (SD) mSv (range: 1.9–11.85 mSv) compared to an equivalent dose of 5.3 ± 1.1 (SD) mSv (range: 2.8–7.3 mSv) for SPECT-CT, corresponding to a 21.2% dose reduction (P = 0.0004).ConclusionDECT imaging shows strong quantitative correlations and qualitative agreements with SPECT-CT for the evaluation of lung perfusion.     

Postoperative spino-pelvic stereoradiography to predict adjacent segment disease

PurposeThe purpose of this study was to identify sagittal spinopelvic parameters predictive of adjacent segment disease (ASD) on postoperative whole spine weight-bearing stereoradiography.Materials and methodsA total of 84 patients with previous spinal fusion surgery and documented radiological follow-up with early weight-bearing postoperative whole spine stereoradiography (EOS® Imaging System) were retrospectively included. A pathological group of 42 patients (9 men, 33 women; mean age, 63.1 ± 11.5 [SD] years) who developed documented ASD (mean follow-up, 76.75 months; range: 31.5–158.5 months) was compared with a control group of 42 asymptomatic patients (7 men, 35 women; mean age, 60.9 ± 11.8 [SD] years) (mean follow-up, 115 months; range: 60–197 months) based on sagittal balance evaluation and routinely used spino-pelvic parameters. Comparisons were made using uni- and multivariate analyses.ResultsAt univariate analysis, patients with ASD had an anteriorly displaced sagittal vertical axis (CAM plumb line) and an inadequate lumbar lordosis (LL) in reference to pelvic incidence (PI) compared to controls. They also had higher C7 slope and C2-C7 offset. At multivariate analysis, C2-C7 offset (OR = 1.152; 95% CI: 1.056–1.256; P = 0.001) and a lack of LL (OR = 5.063; 95% CI: 1.139–22.498; P = 0.033) were significantly associated with ASD.ConclusionAnterior cervical imbalance, reflected by an increase in C2-C7 offset and insufficient restoration of LL are postoperative predictive factors of ASD on stereoradiography.     

Single-source dual energy CT to assess myocardial extracellular volume fraction in aortic stenosis before transcatheter aortic valve implantation (TAVI)

PurposeTo assess myocardial extracellular volume fraction (ECV) measurement provided by a single-source dual-energy computed tomography (SSDE-CT) acquisition added at the end of a routine CT examination before transcatether aortic valve implantation (TAVI) compared to cardiac magnetic resonance imaging (MRI).Materials and methodsTwenty-one patients (10 men, 11 women; mean age, 86 ± 4.9 years [SD]; age range: 71–92 years) with severe aortic stenosis underwent standard pre-TAVI CT with additional cardiac SSDE-CT acquisition 7 minutes after intravenous administration of iodinated contrast material and myocardial MRI including pre- and post-contrast T1-maps. Myocardial ECV and standard deviation (σECV) were calculated in the 16-segments model. ECV provided by SSDE-CT was compared to ECV provided by MRI, which served as the reference. Analyses were performed on a per-segment basis and on a per-patient involving the mean value of the 16-segments.ResultsECV was slightly overestimated by SSDE-CT (29.9 ± 4.6 [SD] %; range: 20.9%–48.3%) compared to MRI (29.1 ± 3.9 [SD] %; range: 22.0%–50.7%) (P < 0.0001) with a bias and limits of agreement of +2.3% (95%CI: −16.1%– + 20.6%) and +2.5% (95%CI: −2.1%– + 7.1%) for per-segment and per-patient-analyses, respectively. Good (r = 0.81 for per-segment-analysis) to excellent (r = 0.97 for per-patient-analysis) linear relationships (both P < 0.0001) were obtained. The σECV was significantly higher at SSDE-CT (P < 0.0001). Additional radiation dose from CT was 1.89 ± 0.38 (SD) mSv (range: 1.48–2.47 mSv).ConclusionA single additional SSDE-CT acquisition added at the end of a standard pre-TAVI CT protocol can provide ECV measurement with good to excellent linear relationship with MRI.     

Medial meniscal ossicles: Associated knee MRI findings in a multicenter case-control study

PurposeThe purpose of this study was to assess and compare the prevalence of meniscal, ligament and cartilage lesions on knee MRI in a series of age- and sex-matched patients with and without medial meniscal ossicle.Materials and methodsForty-two knee MRI examinations obtained in 42 patients (36 men, 6 women; mean age, 42.5 ± 22.2 [SD] years; range: 19–65 years) on which a medial meniscal ossicle was present were compared to 42 knee MRI examinations obtained in 42 age- and sex-matched patients (36 men, 6 women; mean age, 41.8 ± 20.6 [SD] years; range: 19–65 years) on which no medial meniscal ossicles were present. Two radiologists (R1, R2) blinded to the presence of meniscal ossicle by reading only the fat-saturated intermediate-weighted MR images separately assessed the presence of meniscal, ligament and cartilage lesions on these 84 knee MRI examinations. Prevalence of meniscal and ligament lesions and degree of cartilage degradation at MRI were compared between knees with and those without medial meniscal ossicle.ResultsIn knees with medial meniscal ossicle, R1 and R2 detected 33 (79%) and 38 (90%) medial meniscal lesions, respectively that involved the posterior root (n = 25/32 for R1/R2), the posterior horn (n = 19/14 for R1/R2) or the body (n = 8/10 for R1/R2). The prevalence of posterior root tear (60% [25/42]/76% [32/42] for R1/R2) and that of anterior cruciate ligament (ACL) lesions (48% [20/42]/57% [24/42] for R1/R2) as well as the medial cartilage degradation score (3.35 ± 0.87 [SD] for R1 and 3.92 ± 0.78 [SD] for R2) were significantly greater in knees with than in knees without medial meniscal ossicle (root lesions: P < 0.01 for both readers; ACL lesions and medial cartilage score: P < 0.01 for both readers).ConclusionOn MRI examination, knees with a medial meniscal ossicle demonstrate a greater frequency of medial posterior root tear and of ACL lesions and a greater degree of medial femoro-tibial cartilage degradation by comparison with knees without medial ossicle.     

Comparison of breast density assessment between human eye and automated software on digital and synthetic mammography: Impact on breast cancer risk

PurposeTo evaluate the agreement between automatic assessment software of breast density based on artificial intelligence (AI) and visual assessment by a senior and a junior radiologist, as well as the impact on the assessment of breast cancer risk (BCR) at 5 years.Materials and methodsWe retrospectively included 311 consecutive women (mean age, 55.6 ± 8.5 [SD]; range: 40–74 years) without a personal history of breast cancer who underwent routine mammography between January 1, 2019 and February 28, 2019. Mammographic breast density (MBD) was independently evaluated by a junior and a senior reader on digital mammography (DM) and synthetic mammography (SM) using BI-RADS (5th edition) and by an AI software. For each MBD, BCR at 5 years was estimated per woman by the AI software. Interobserver agreement for MBD between the two readers and the AI software were evaluated by quadratic κ coefficients. Reproducibility of BCR was assessed by intraclass correlation coefficient (ICC).ResultsAgreement for MBD assessment on DM and SM was almost perfect between senior and junior radiologists (κ = 0.88 [95% CI: 0.84–0.92] and κ = 0.86 [95% CI: 0.82–0.90], respectively) and substantial between the senior radiologist and AI (κ = 0.79; 95% CI: 0.73–0.84). There was substantial agreement between DM and SM for the senior radiologist (κ = 0.79; 95% CI: 0.74–0.84). BCR evaluation at 5 years was highly reproducible between the two radiologists on DM and SM (ICC = 0.98 [95% CI: 0.97–0.98] for both), between BCR evaluation based on DM and SM evaluated by the senior (ICC = 0.96; 95% CI: 0.95–0.97) or junior radiologist (ICC = 0.97; 95% CI: 0.96–0.98) and between the senior radiologist and AI (ICC = 0.96; 95% CI: 0.95–0.97).ConclusionThis preliminary study demonstrates a very good agreement for BCR evaluation based on the evaluation of MBD by a senior radiologist, junior radiologist and AI software.     

How is quality of life after total hip replacement related to the reconstructed anatomy? A study with low-dose stereoradiography

PurposeThe purpose of this study was to evaluate the relationships between the three-dimensional anatomy of operated hip in standing position using low-dose stereo-radiography imaging system and postoperative hip disability and osteoarthritis outcome score (HOOS) after total hip arthroplasty (THA).Material and methodsA total of 123 patients who underwent THA during a one-year period were included. There were 50 men and 73 women with a mean age of 67.3 ± 13.6 (SD) years (range: 19–89 years). All patients underwent pre- and postoperative low-dose stereo-radiography examination and completed a HOOS form (score from 0 to 100, 100 for full satisfaction). We recorded 16 anatomical parameters before THA, and 15 after THA. After binary transformation of HOOS score using 70 as threshold value, outcome was assessed using logistic or generalised linear models.ResultsA total of 103 patients (103/123; 83.7%) had a HOOS score ≥ 70 and were considered as the satisfied group. A significant difference in pelvic incidence (the angle between a line perpendicular to the sacral plate at its midpoint and a line connecting the same point to the centre of the bicoxofemoral axis) was found between the satisfied 56.4 ± 10.4 (SD)° (range: 31–85°) and the unsatisfied group 48.7 ± 8.9 (SD)° (range: 40–65) (P = 0.006). The relative variation of offset (distance from the centre of rotation of the femoral head to a line bisecting the long axis of the femur) compared to the contralateral hip was ?7% in the satisfied group and 7.2% in the unsatisfied group (P = 0.01).ConclusionPelvic incidence, a parameter independent of the reconstructed anatomy, probably influences the quality of life of patients with THA, via pelvic compensatory capabilities. A loss of femoral offset negatively influences the satisfaction of patients.     

COVID-19: A qualitative chest CT model to identify severe form of the disease

PurposeThe purpose of this study was to identify clinical and chest computed tomography (CT) features associated with a severe form of coronavirus disease 2019 (COVID-19) and to propose a quick and easy to use model to identify patients at risk of a severe form.Materials and methodsA total of 158 patients with biologically confirmed COVID-19 who underwent a chest CT after the onset of the symptoms were included. There were 84 men and 74 women with a mean age of 68 ± 14 (SD) years (range: 24–96 years). There were 100 non-severe and 58 severe cases. Their clinical data were recorded and the first chest CT examination was reviewed using a computerized standardized report. Univariate and multivariate analyses were performed in order to identify the risk factors associated with disease severity. Two models were built: one was based only on qualitative CT features and the other one included a semi-quantitative total CT score to replace the variable representing the extent of the disease. Areas under the ROC curves (AUC) of the two models were compared with DeLong's method.ResultsCentral involvement of lung parenchyma (P < 0.001), area of consolidation (P < 0.008), air bronchogram sign (P < 0.001), bronchiectasis (P < 0.001), traction bronchiectasis (P < 0.011), pleural effusion (P < 0.026), large involvement of either one of the upper lobes or of the middle lobe (P < 0.001) and total CT score ≥ 15 (P < 0.001) were more often observed in the severe group than in the non-severe group. No significant differences were found between the qualitative model (large involvement of either upper lobes or middle lobe [odd ratio (OR) = 2.473], central involvement [OR = 2.760], pleural effusion [OR = 2.699]) and the semi-quantitative model (total CT score ≥ 15 [OR = 3.342], central involvement [OR = 2.344], pleural effusion [OR = 2.754]) with AUC of 0.722 (95% CI: 0.638–0.806) vs. 0.739 (95% CI: 0.656–0.823), respectively (P = 0.209).ConclusionWe have developed a new qualitative chest CT-based multivariate model that provides independent risk factors associated with severe form of COVID-19.     

Differences in right ventricular-pulmonary vascular coupling and clinical indices between repaired standard tetralogy of Fallot and repaired tetralogy of Fallot with pulmonary atresia

PurposeThe purpose of this study was to compare ventricular vascular coupling ratio (VVCR) between patients with repaired standard tetralogy of Fallot (TOF) and those with repaired TOF-pulmonary atresia (TOF-PA) using cardiovascular magnetic resonance (CMR).Materials and methodsPatients with repaired TOF aged > 6 years were prospectively enrolled for same day CMR, echocardiography, and exercise stress test following a standardized protocol. Sanz's method was used to calculate VVCR as right ventricle (RV) end-systolic volume/pulmonary artery stroke volume. Regression analysis was used to examine associations with exercise test parameters, New York Heart Association (NYHA) class, RV size and biventricular systolic function.ResultsA total of 248 subjects were included; of these 222 had repaired TOF (group I, 129 males; mean age, 15.9 ± 4.7 [SD] years [range: 8–29 years]) and 26 had repaired TOF-PA (group II, 14 males; mean age, 17.0 ± 6.3 [SD] years [range: 8–29 years]). Mean VVCR for all subjects was 1.54 ± 0.64 [SD] (range: 0.43–3.80). Mean VVCR was significantly greater in the TOF-PA group (1.81 ± 0.75 [SD]; range: 0.78–3.20) than in the standard TOF group (1.51 ± 0.72 [SD]; range: 0.43–3.80) (P = 0.03). VVCR was greater in the 68 NYHA class II subjects (1.79 ± 0.66 [SD]; range: 0.75–3.26) compared to the 179 NYHA class I subjects (1.46 ± 0.61 [SD]; range: 0.43–3.80) (P < 0.001).ConclusionNon-invasive determination of VVCR using CMR is feasible in children and adolescents. VVCR showed association with NYHA class, and was worse in subjects with repaired TOF-PA compared to those with repaired standard TOF. VVCR shows promise as an indicator of pulmonary artery compliance and cardiovascular performance in this cohort.