Morphological imaging and CT histogram analysis to differentiate pancreatic neuroendocrine tumor grade 3 from neuroendocrine carcinoma

PurposeTo compare morphological imaging features and CT texture histogram parameters between grade 3 pancreatic neuroendocrine tumors (G3-NET) and neuroendocrine carcinomas (NEC).Materials and methodsPatients with pathologically proven G3-NET and NEC, according to the 2017 World Health Organization classification who had CT and MRI examinations between 2006-2017 were retrospectively included. CT and MRI examinations were reviewed by two radiologists in consensus and analyzed with respect to tumor size, enhancement patterns, hemorrhagic content, liver metastases and lymphadenopathies. Texture histogram analysis of tumors was performed on arterial and portal phase CT images. images. Morphological imaging features and CT texture histogram parameters of G3-NETs and NECs were compared.ResultsThirty-seven patients (21 men, 16 women; mean age, 56 ± 13 [SD] years [range: 28-82 years]) with 37 tumors (mean diameter, 60 ± 46 [SD] mm) were included (CT available for all, MRI for 16/37, 43%). Twenty-three patients (23/37; 62%) had NEC and 14 patients (14/37; 38%) had G3-NET. NECs were larger than G3-NETs (mean, 70 ± 51 [SD] mm [range: 18 - 196 mm] vs. 42 ± 24 [SD] mm [range: 8 - 94 mm], respectively; P = 0.039), with more tumor necrosis (75% vs. 33%, respectively; P = 0.030) and lower attenuation on precontrast (30 ± 4 [SD] HU [range: 25-39 HU] vs. 37 ± 6 [SD] [range: 25-45 HU], respectively; P = 0.002) and on portal venous phase CT images (75 ± 18 [SD] HU [range: 43 - 108 HU] vs. 92 ± 19 [SD] HU [range: 46 - 117 HU], respectively; P = 0.014). Hemorrhagic content on MRI was only observed in NEC (P = 0.007). The mean ADC value was lower in NEC ([1.1 ± 0.1 (SD)] × 10⁻³ mm²/s [range: (0.91 - 1.3) × 10⁻³ mm²/s] vs. [1.4 ± 0.2 (SD)] × 10⁻³ mm²/s [range: (1.1 - 1.6) × 10⁻³ mm²/s]; P = 0.005). CT histogram analysis showed that NEC were more heterogeneous on portal venous phase images (Entropy-0: 4.7 ± 0.2 [SD] [range: 4.2-5.1] vs. 4.5 ± 0.4 [SD] [range: 3.7-4.9]; P = 0.023).ConclusionPancreatic NECs are larger, more frequently hypoattenuating and more heterogeneous with hemorrhagic content than G3-NET on CT and MRI.     

CT and MRI characteristics of ovarian mature teratoma in patients with anti-N-methyl-D-aspartate receptor encephalitis

PurposeThe purpose of this study was to determine the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics of ovarian mature teratoma in patients with anti-N-methyl-d-aspartate receptor encephalitis (NMDAR-E).Materials and MethodsA total of 125 women (mean age, 40.9 ± 17.8 [SD] years; age range: 12–85 years) with 146 histopathologically or radiologically proven ovarian mature teratomas who underwent preoperative CT and MRI examinations were retrospectively included. Eight patients with 11 teratomas had NMDAR-E, whereas 117 patients with 135 teratomas did not have NMDAR-E. CT and MRI examinations were retrospectively reviewed and teratomas in patients with NMDAR-E were compared to those in patients without NMDAR-E. Comparisons were performed using Mann-Whitney U test or Fisher exact test.ResultsIn patients with NMDAR-E, maximum diameter of teratomas (26.1 ± 9.3 [SD] mm), prevalence of teeth/calcification (36%) and rate of occupation by fat components (26%) were lower than those in patients without NMDAR-E (67.0 ± 37.6 [SD] mm [P < 0.01]; 75% [P < 0.05]; and 65%[P < 0.01], respectively). More than 75% of space was occupied by fat components in 76/135 teratomas (56%) in patients without NMDAR-E, whereas this was not observed in any teratoma in patients without NMDAR-E.ConclusionBy comparison with teratomas in patients without NMDAR-E, teratomas in patients with NMDAR-E are smaller, have few teeth/calcification, and the amount of space occupied by fat components is smaller.     

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.     

Computed tomography features of acinar cell carcinoma of the pancreas

PurposeTo report the computed tomography (CT) features of pancreatic acinar cell carcinoma (ACC) and identify CT features that may help discriminate between pancreatic ACC and pancreatic ductal adenocarcinoma (PDA).Materials and methodsThe CT examinations of 20 patients (13 men, 7 women; mean age, 66.5 ± 10.7 [SD] years; range: 51–88 years) with 20 histopathologically proven pancreatic ACC were reviewed. CT images were analyzed qualitatively and quantitatively and compared to those obtained in 20 patients with PDA. Comparisons were performed using univariate analysis with a conditional logistic regression model.ResultsPancreatic ACC presented as an enhancing (20/20; 100%), oval (15/20; 75%), well-delineated (14/20; 70%) and purely solid (13/20; 65%) pancreatic mass with a mean diameter of 52.6 ± 28.0 (SD) mm (range: 24–120 mm) in association with visible lymph nodes (14/20; 70%). At univariate analysis, well-defined margins (Odds ratio [OR], 7.00; P = 0.005), nondilated bile ducts (OR, 9.00; P = 0.007), visible lymph nodes (OR, 4.33; P = 0.028) and adjacent organ involvement (OR, 5.67; P = 0.02) were the most discriminating CT features to differentiate pancreatic ACC from PDA. When present, lymph nodes were larger in patients with pancreatic ACC (14 ± 4.8 [SD]; range: 7–25 mm) than in those with PDA (8.8 ± 4.1 [SD]; range: 5–15 mm) (P = 0.039).ConclusionOn CT, pancreatic ACC presents as an enhancing, predominantly oval and purely solid pancreatic mass that most frequently present with no bile duct dilatation, no visible lymph nodes, no adjacent organ involvement and larger visible lymph nodes compared to PDA.     

CT-guided biopsy of lung nodules with pleural contact: Comparison of two puncture routes

PurposeThe purpose of this study was to retrospectively compare two puncture routes (transpleural vs. transpulmonary) for computed tomography (CT) fluoroscopy-guided cutting needle biopsy of lung nodules with pleural contact.Patients and methodsA total of 102 patients (72 men; mean age, 71.1 ± 9.5 [SD] years) were included and 102 biopsies of 102 lung nodules (mean size, 16.7 ± 5.9 [SD] mm; range, 6.0–29.4 mm; mean length of pleural contact, 10.1 ± 4.2 [SD] mm; range, 2.8–19.6 mm) were analyzed. All procedures were classified as biopsies via the direct transpleural route or the transpulmonary route. The patient-, lesion-, and biopsy-related variables, diagnostic yields, and incidence of complications were compared between the two routes.ResultsBiopsy was performed via the direct transpleural route (n = 59; 57.8%) and transpulmonary route (n = 43; 42.2%). In the transpulmonary route group, the mean distance of the intrapulmonary pathway was 17.7 ± 9.4 [SD] mm (range: 4.1–47.6 mm; P < 0.001) and the introducer needle trajectory angle of < 45° was significantly observed (8.5% [5/59] vs. 60.5% [26/43]; P < 0.001). There was no significant difference in diagnostic accuracy between the direct transpleural and transpulmonary routes (93.2% [55/59] vs. 90.7% [39/43]; P = 0.718). The frequencies of all complications (64.4% [38/59] vs. 97.7% [42/43]; P < 0.001), pneumothorax (33.9% [20/59] vs. 65.1% [28/43]; P = 0.003), pneumothorax with chest tube placement (3.4% [2/59] vs. 18.6% [8/43]; P = 0.016), and pulmonary hemorrhage (47.5% [28/59] vs. 76.7% [33/43]; P = 0.004) were significantly lower in the direct transpleural group.ConclusionDirect transpleural route is recommended for CT fluoroscopy-guided biopsy of lung nodules with pleural contact because it is safer and yields similar diagnostic accuracy than transpulmonary route.     

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.     

Myocardial deformation assessment in patients with precapillary pulmonary hypertension: A cardiac magnetic resonance study

PurposeThe purpose of this study was to investigate right atrial and ventricular strain parameters on cardiac magnetic resonance (CMR) in patients with precapillary pulmonary hypertension (PPH) and whether they can aid in the assessment of PPH prognosis.Materials and methodsAdult patients with groups 1 and 4 PPH were invited to participate in the study. Age- and sex-matched healthy volunteers were also recruited as controls. At baseline, patients underwent clinical examination, N-terminal pro-B-type natriuretic peptide measurement and CMR with feature tracking post-processing (CMR-FT). Healthy controls underwent only CMR-FT. The study's primary endpoint was clinical failure, defined as death, hospitalization or demonstrable clinical deterioration during follow-up. Patients who were unable to perform 6-minute walking test due to musculoskeletal disorders were excluded from the study.ResultsThirty-six patients (8 men, 28 women; mean age, 50.6 ± 13.8 [SD] years [range: 18.6–78.5 years]) and 12 healthy control subjects (5 mean, 7 women; mean age, 40.6 ± 13.5 [SD] years [range: 23.1–64.4 years]) were recruited. Right ventricular global longitudinal strain (GLS) was significantly impaired in PPH patients (?20.2 ± 5.3 [SD] % [range: ?28.8 to ?9.1%] vs. ?28.4 ± 3.1% [?33.7 to ?22.7%] respectively, P < 0.001). The right atrial GLS was significantly impaired in PPH compared to healthy controls (?19.9 ± 4.5% [range: ?28.6 to ?3.6%] vs. ?26.5 ± 4.2% [range: ?32.8 to ?15.8%] respectively) (P < 0.001). Clinical failure occurred in 19 (19/36, 53%) of patients. Right ventricular GLS predicted clinical failure most reliably among CMR parameters (?22.6 ± 3.8 [SD] % [range: ?27.6 to ?12.7%] for patients without clinical failure vs. ?18 ± 5.6 [SD] % [range: ?28.8 to ?9.1%] for patients with clinical failure; hazard ratio [HR] = 1.85; P = 0.007; area under the AUC curve = 0.75). Lower absolute right atrial GLS was significantly associated with clinical failure (?22.7 ± 3.0 [SD] % [range: ?28.6 to ?17.7%] for patients without clinical failure vs. ?16.9 ± 5.8 [SD] % [range: ?24.2 to ?3.6%] for patients with clinical failure) (HR = 1.53; P = 0.035).ConclusionCMR feature tracking-derived myocardial strain parameters of both the right atrium and ventricle can assist clinicians in the prognosis of PPH.     

Combined subtalar distraction arthrodesis with peroneus brevis tenotomy for posttraumatic subtalar arthritis

BackgroundSubtalar distraction arthrodesis is advocated as a salvage procedure for isolated posttraumatic subtalar arthritis. This study aimed at evaluating combined subtalar distraction arthrodesis with peroneus brevis tenotomy for such cases.MethodsTwenty patients with isolated posttraumatic subtalar arthritis managed by combined subtalar distraction arthrodesis and peroneus brevis tenotomy were reviewed for a retrospective study. The American orthopaedic foot and ankle society [AOFAS] hindfoot scoring, talocalcaneal height [TCH], talocalcaneal angle [TCA] and heel valgus angle [HVA] were used for both pre and postoperative assessments.ResultsThe mean postoperative [TCH] [70.3 ± 1.9 mm] was statistically better than the preoperative value [64.7 ± 2.2 mm] [p < 0.001]. There was a statistically significant decrease in [HVA] [p < 0.001]. On the contrary, there was a statistically significant increase in both [AOFAS] hindfoot scoring and the [TCA] [p < 0.001].ConclusionsApplying this technique for isolated posttraumatic subtalar arthritis with peroneal tendinitis improved both lateral retromalleolar swelling and deformity correction.     

Radiomics in the evaluation of lung nodules: Intrapatient concordance between full-dose and ultra-low-dose chest computed tomography

PurposeThe purpose of this study was to retrospectively evaluate the quantitative and qualitative intrapatient concordance of pulmonary nodule risk assessment by commercially available radiomics software between full-dose (FD) chest-CT and ultra-low-dose (ULD) chest CT.Materials and methodsBetween July 2013 and September 2015, 68 patients (52 men and16 women; mean age, 65.5 ± 10.6 [SD] years; range: 35–87 years) with lung nodules ≥ 5 mm and < 30 mm who underwent the same day FD chest CT (helical acquisition; 120 kV; automated tube current modulation) and ULD chest CT (helical acquisition; 135 kV; 10 mA fixed) were retrospectively included. Each nodule on each acquisition was assessed by a commercial radiomics software providing a similarity malignancy index (mSI), classifying it as “benign-like” (mSI < 0.1); “malignant-like” (mSI > 0.9) or “undetermined” (0.1 ≤ mSI ≤ 0.9). Intrapatient qualitative agreement was evaluated with weighted Cohen–Kappa test and quantitative agreement with intraclass correlation coefficient (ICC).ResultsNinety-nine lung nodules with a mean size of 9.14 ± 4.3 (SD) mm (range: 5–25 mm) in 68 patients (mean 1.46 nodule per patient; range: 1–5) were assessed; mean mSI was 0.429 ± 0.331 (SD) (range: 0.001–1) with FD chest CT (22/99 [22%] “benign-like”, 67/99 [68%] “undetermined” and 10/99 [10%] “malignant-like”) and mean mSI was 0.487 ± 0.344 (SD) (range: 0.002–1) with ULD chest CT (20/99 [20%] “benign-like”, 59/99 [60%] “undetermined” and 20/99 [20%] “malignant-like”). Qualitative and quantitative agreement of FD chest CT with ULD chest CT were “good” with Kappa value of 0.60 (95% CI: 0.46–0.74) and ICC of 0.82 (95% CI: 0.73–0.87), respectively.ConclusionA good agreement in malignancy similarity index can be obtained between ULD chest CT and FD chest CT using radiomics software. However, further studies must be done with more case material to confirm our results and elucidate the diagnostic capabilities of radiomics software using ULD chest CT for lung nodule characterization by comparison with FD chest CT.     

Optimal acquisition time to discriminate between breast cancer subtypes with contrast-enhanced cone-beam CT

PurposeTo identify the optimal acquisition time to best discriminate between benign and malignant breast lesions on contrast-enhanced cone beam CT (CE-CBCT) and evaluate the potential of CE-CBCT to differentiate between breast cancer subtypes.Material and methodA total of 98 women with a mean age of 49 ± 10 (SD) years (range: 29–77 years) with 100 BI-RADS 4 or 5 breast lesions were prospectively included. CE-CBCT images were obtained at 1- and 2-min after intravenous administration of iodinated contrast material. Contrast enhancement of breast lesions on CE-CBCT were evaluated and compared between different subtypes. Cut-off values for best discriminating between benign and malignant breast lesions with CE-CBCT were obtained from receiver operating characteristic curves.ResultsMalignant breast lesions showed greater enhancement than benign ones at 1-min (67.28 ± 39.79 [SD] HU vs. 42.27 ± 40.31 [SD] HU, respectively; P = 0.007) and 2-min (70.93 ± 38.05 [SD] HU vs. 48.94 ± 41.83 [SD] HU, respectively; P = 0.016) after intravenous administration of contrast material. At 1-min after intravenous administration of contrast material, an optimal cut-off value of 54.43 HU was found to best discriminate between malignant and benign breast lesions (AUC = 0.681; 95%CI: 0.558–0.805; P = 0.006) yielding 69.0% sensitivity (95%CI: 56.9–79.5%) and 69.2% specificity (95% CI: 48.2–85.7%). At 2-min, an optimal cut-off value of 72.65 HU was found to best discriminate between malignant and benign breast lesions (AUC = 0.654; 95%CI: 0.535–0.774; P = 0.020) yielding 50.7% sensitivity (95%CI: 38.6–62.8%) and 80.8% specificity (95%CI: 60.6–93.4%). CE-CBCT helped differentiate between immunohistochemical subtypes of breast lesions with lowest enhancement for triple negative lesions. No differences in enhancement were found among histopathological subtypes lesions at 1-min (P = 0.478) and 2-min (P = 0.625).ConclusionCE-CBCT helps discriminate between malignant and benign breast lesions, with best capabilities obtained at 1-min after intravenous administration of contrast material. For malignant lesions, quantitative analysis of enhancement on CE-CBCT helps differentiate between immunohistochemical subtypes.     

Patterns of Physical Activity Progression in Patients With COPD

IntroductionAlthough mean physical activity in COPD patients declines by 400?500 steps/day annually, it is unknown whether the natural progression is the same for all patients. We aimed to identify distinct physical activity progression patterns using a hypothesis-free approach and to assess their determinants.MethodsWe pooled data from two cohorts (usual care arm of Urban Training [NCT01897298] and PROactive initial validation [NCT01388218] studies) measuring physical activity at baseline and 12 months (Dynaport MoveMonitor). We identified clusters (patterns) of physical activity progression (based on levels and changes of steps/day) using k-means, and compared baseline sociodemographic, interpersonal, environmental, clinical and psychological characteristics across patterns.ResultsIn 291 COPD patients (mean ± SD 68 ± 8 years, 81% male, FEV₁ 59 ± 19%_pred) we identified three distinct physical activity progression patterns: Inactive (n = 173 [59%], baseline: 4621 ± 1757 steps/day, 12-month change (?): ∧487 ± 1201 steps/day), Active Improvers (n = 49 [17%], baseline: 7727 ± 3275 steps/day, ?: + 3378 ± 2203 steps/day) and Active Decliners (n = 69 [24%], baseline: 11 267 ± 3009 steps/day, ?: ∧2217 ± 2085 steps/day). After adjustment in a mixed multinomial logistic regression model using Active Decliners as reference pattern, a lower 6-min walking distance (RRR [95% CI] 0.94 [0.90?0.98] per 10 m, P = .001) and a higher mMRC dyspnea score (1.71 [1.12?2.60] per 1 point, P = .012) were independently related with being Inactive. No baseline variable was independently associated with being an Active Improver.ConclusionsThe natural progression in physical activity over time in COPD patients is heterogeneous. While Inactive patients relate to worse scores for clinical COPD characteristics, Active Improvers and Decliners cannot be predicted at baseline.     

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.     

Differentiation between benign and malignant ovarian masses using multiparametric MRI

PurposeTo investigate the capabilities of multiparametric MRI including dynamic contrast enhanced (DCE) perfusion and diffusion-weighted imaging (DWI) to discriminate between benign and malignant ovarian masses.MethodsA total of 43 women with a total of 43 ovarian masses were retrospectively included. They had a mean age of 51.26 ± 18.05 (SD) years (range: 20–88 years). Twenty women had benign and 23 had malignant ovarian tumors. All women had multiparametric MRI examinations including DWI (b50-b800) and DCE perfusion imaging at 1–5 T. Results of DWI (apparent diffusion coefficient [ADC], b-800) and DCE imaging (volume transfer coefficient [K^trans], rate constant [K_ep], interstitial volume [V_e], initial area under the curve [iAUC]) were compared between benign and malignant ovarian masses.ResultsMean ADC was significantly lowed in malignant tumors (0.92 ± 0.25 [SD] ×10⁻³ mm²/s (range: 0.6–1.6 × 10⁻³ mm²/s) than in benign tumors (1.37 ± 0.69 [SD] × 10⁻³ mm²/s; range: 0.4–2.9 × 10⁻³ mm²/s) (P = 0.011). B-800 was significantly greater in malignant tumors (80.61 ± 24.73 [SD] s/mm²; range: 24–110 s/mm²) than in benign ones (61.15 ± 22.17 [SD] s/mm²; range: 38–155 s/mm²) (P = 0.010).  K^trans was lower in benign tumors (0.13 ± 0.06 [SD] min⁻¹; range: 0–0.2 min⁻¹) than in malignant ones (0.25 ± 0.16 [SD] min⁻¹; range: 0.1–0.8 min⁻¹) (P = 0.002).  K_ep was significantly greater in malignant tumors (0.55 ± 0.19 [SD] min⁻¹; range: 0.1–1.9 min⁻¹) than in benign ones (0.44 ± 0.38 [SD] min⁻¹; range: 0.2–1.1 min⁻¹) (P = 0.003). iAUC was greater in malignant tumors (15.59 ± 7.98 [SD] mM/min; range: 6.6–42.1 mM/min) than in benign ones (7.98 ± 5.06 [SD] mM/min; range: 0.2–17.7 mM/min) (P = 0.001). No differences in V_e were found between benign and malignant masses (P = 0.084). The area under the ROC curve was significant for all parameters but V_e. Logistic regression analysis revealed 5.590 and 11.637 times higher malignancy risk for an ADC ≤ 0.93 × 10⁻³ mm²/s and an iAUC ≥ 13.88 mM/min, respectively.ConclusionMultiparametric MRI has high accuracy in discrimination between benign and malignant ovarian masses. Therefore, adding these methods to the more common MRI protocol can help select the best treatment option in women with ovarian mass.     

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.     

Increased cortical area and thickness in the distal radius in subjects with SHOX-gene mutation

IntroductionShort-stature homeobox (SHOX) gene haploinsufficiency may cause skeletal dysplasia including Léri–Weill Dyschondrosteosis (LWD), a clinical entity characterised by the triad of low height, mesomelic disproportion and Madelung's deformity of the wrist. Bone microarchitecture and estimated strength in adult SHOX mutation carriers have not been examined.MethodsTwenty-two subjects with a SHOX mutation including 7 males and 15 females with a median age of 38.8 [21.1–52.2] years were recruited from five unrelated families. The control group consisted of 22 healthy subjects matched on age and sex. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. Bone geometry, volumetric density, microarchitecture and finite element estimated (FEA) bone strength were measured using high-resolution peripheral quantitative computed tomography (HR-pQCT). A full region of interest (ROI) image analysis and height-matched ROI analyses adjusting for differences in body height between the two groups were performed.ResultsAreal BMD and T-scores showed no significant differences between cases and controls. Total radius area was smaller in cases than controls (207 [176–263] vs. 273 [226–298] mm, p < 0.01). Radius cortical bone area (74 ± 20 vs. 58 ± 17 mm², p = 0.01) and thickness (1.16 ± 0.30 vs. 0.84 ± 0.26 mm, p < 0.01) as well as total density (428 ± 99 vs. 328 ± 72 mg/cm³, p < 0.01) were higher in SHOX mutation carriers compared to controls. Radius trabecular bone area (119 [103–192] vs. 202 [168–247] mm², p < 0.01) and trabecular number (1.61 [1.46–2.07] vs. 1.89 [1.73–2.08] mm^− 1, p = 0.01) were smaller in SHOX mutation carriers. Tibia trabecular thickness was lower in cases (0.067 ± 0.012 vs. 0.076 ± 0.012 mm, p = 0.01). These results remained significant after adjustment for differences in body height and when restricting analyses to females. There were no differences in BMD, radius and tibia cortical porosity or FEA failure load between groups. A segment of cortical bone defect was identified in the distal radius adjacent to ulna in five unrelated SHOX mutation carriers.ConclusionSubjects with a SHOX mutation presented with a different bone geometry in radius and tibia while there were no differences in BMD or failure load compared to controls, suggesting that mutations in SHOX gene may have an impact on bone microarchitecture albeit not bone strength.     

Bone structure and geometry in young men: The influence of smoking,alcohol intake and physical activity

BackgroundThe development of osteoporosis is influenced by peak bone mass attained in youth — the influence of lifestyle factors upon which is poorly described, especially amongst males. We sought to address this issue in a large scale study.MethodsHip bone mineral density (dual X-ray absorptiometry, DXA), bone microarchitecture (calcaneal quantitative ultrasound, QUS) and femoral geometry (magnetic resonance imaging, MRI) were characterised in 723 healthy male military recruits (mean ± S.E. age 19.92 ± 0.09 years [range 16–18 years], height 177.67 ± 0.24 cm, weight 73.17 ± 0.37 kg) on entry to UK Army training. Association was sought with prior physical activity, smoking status and alcohol intake.ResultsDXA measures were made in 651, MRI measures in 650, and QUS measures in 572 recruits. Increasing levels of weight-bearing physical activity enhanced periostial bone apposition, increases in both total hip and femoral neck bone mineral density (BMD; p ≤ 0.0001 in both cases), and cortical [p < 0.0001] and periostial bone volumes [p = 0.016]. Smoking habit was associated with preserved bone geometry, but worse BMD [p = 0.0001] and QUS characteristics [p ≤ 0.0005]. Moderate alcohol consumption was associated with greater BMD [p ≤ 0.015].ConclusionsWhilst exercise (and perhaps moderate alcohol intake) is beneficial to bone morphometry, smoking is detrimental to bone mineral density in young males notable for the likely short duration of smoking to influence skeletal properties. However, differences in socio-economic status, lifestyle and related environmental factors may to some extent confound our results.     

CT evaluation of patent artery after percutaneous cryoablation of renal cell carcinoma

PurposeThe purpose of this retrospective study was to determine the incidence of persistent patent artery after percutaneous cryoablation of renal cell carcinoma (RCC) and the relationship between patent arteries one month after cryoablation and early tumor progression.Materials and methodsOne hundred and fifty-nine patients (112 men, 47 women; mean age, 63.6 ± 14.6 [SD] years; age range: 21–91 years) who underwent percutaneous cryoablation for 186 RCCs (mean diameter, 1.9 ± 0.6 [SD] cm; range: 0.7–4.0 cm) were retrospectively included. After cryoablation, patients underwent contrast-enhanced computed tomography (CT) with ≤ 2-mm slice thickness within one week from cryoablation, and at one, three, and six months. The time course of patent artery in the ablated renal parenchyma after cryoablation was the primary endpoint. The relationships between patent arteries one month after cryoablation and treatment effectiveness, tumor vascularity, tumor enhancement one month after cryoablation, tumor subtype, and renal function changes were evaluated as secondary endpoints.ResultsCT showed patent arteries in the ablated renal parenchyma within one week in 166 RCCs (89.2%), at one month in 54 RCCs (29.0%), at three months in 8 RCCs (4.3%), and at six months in 2 RCCs (1.1%). The presence of patent artery one month after cryoablation was significantly associated with tumor enhancement at the same time point (P = 0.015). There was no association between patent arteries one month after cryoablation and treatment effectiveness (P = 0.693).ConclusionPatent arteries in the ablated renal parenchyma are commonly observed on CT examination after percutaneous cryoablation of RCC. However, they gradually disappear and do not require specific treatment.     

Reduced nontarget embolization and increased targeted delivery with a reflux-control microcatheter in a swine model

PurposeTo evaluate the potential differences in non-target embolization and vessel microsphere filling of a reflux-control microcatheter (RCM) compared to a standard end-hole microcatheter (SEHM) in a swine model.Materials and methodsRadiopaque microspheres were injected with both RCM and SEHM (2.4-Fr and 2.7-Fr) in the kidneys of a preclinical swine model. Transarterial renal embolization procedures with RCM or SEHM were performed in both kidneys of 14 pigs. Renal arteries were selectively embolized with an automated injection protocol of radio-opaque microspheres. Ex-vivo X-ray microtomography images of the kidneys were utilized to evaluate the embolization by quantification of the deposition of injected microspheres in the target vs. the non-target area of injection. X-ray microtomography images were blindly analyzed by five interventional radiologists. The degree of vessel filling and the non-target embolization were quantified using a scale from 1 to 5 for each parameter. An analysis of variance was used to compare the paired scores.ResultsTotal volumes of radio-opaque microspheres injected were similar for RCM (11.5 ± 3.6 [SD] mL; range: 6–17 mL) and SEHM (10.6 ± 5.2 [SD] mL; range: 4–19 mL) (P = 0.38). The voxels enhanced ratio in the target (T) vs. non-target (NT) areas was greater with RCM (T = 98.3% vs. NT = 1.7%) than with SEHM (T = 89% vs. NT = 11%) but the difference was not significant (P = 0.30). The total score blindly given by the five interventional radiologists was significantly different between RCM (12.3 ± 2.1 [SD]; range: 6–15) and the standard catheter (11.3 ± 2.5 [SD]; range: 4–15) (P = 0.0073), with a significant decrease of non-target embolization for RCM (3.8 ± 1.3 [SD]; range: 3.5–4.2) compared to SEHM (3.2 ± 1.5 [SD]; range: 2.9–3.5) (P = 0.014).ConclusionIn an animal model, RCM microcatheters reduce the risk of non-target embolization from 11% to 1.7%, increasing the delivery of microspheres of 98% to the target vessels, compared to SEHM microcatheters.     

Comparison of conventional magnetic resonance imaging and diffusion-weighted imaging in the differentiation of bone plasmacytoma from bone metastasis in the extremities

PurposeTo compare conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in the differentiation of bone plasmacytoma from bone metastasis in the extremities.Materials and methodsA total of 65 patients with 27 bone plasmacytomas (11 men; mean age, 63.6 ± 8.2 [SD] years) and 38 patients with bone metastases (20 men; mean age, 64.1 ± 11.5 [SD] years) were retrospectively included. Plasmacytomas and metastases were compared for size, peritumoral edema, signal intensity (SI), SI pattern, apparent diffusion coefficient (ADC) values and standard deviation (SD) of ADC. Receiver operating characteristic analysis with area under the curve (AUC) was used to calculate sensitivity, specificity, and accuracy of MRI and DWI for the diagnosis of plasmacytoma according to a defined cut-off value.ResultsOn conventional MRI, plasmacytomas showed less peritumoral edema (22% vs. 71%; P < 0.001), were more often hyperintense on T1-weighted image (48% vs. 18%; P = 0.022) and more homogeneous on T2-weighted image (78% vs. 26%; P < 0.001) and contrast-enhanced T1-weighted images (70% vs. 25%; P = 0.001) than bone metastases. Mean ADC value and SD of ADC were significantly lower in bone plasmacytomas (760.1 ± 196.9 [SD] μm²/s and 161.5 ± 62.7 [SD], respectively) than in bone metastases (1214.2 ± 382.6 [SD] μm²/s and 277.0 ± 110.3 [SD], respectively) (P < 0.001). Using an ADC value ≤ 908.3 μm²/s, DWI yielded 88% sensitivity and 78% specificity for the diagnosis of plasmacytoma. ADC value yielded best area under the curve (AUC = 0.913), followed by SD of ADC (AUC = 0.814) and homogeneity on T2-weighted images (AUC = 0.757). The combination of conventional MRI and DWI (AUC = 0.894) showed improved diagnostic performance over conventional MRI alone (AUC= 0.843) for discriminating between plasmacytoma and metastasis.ConclusionConventional MRI in combination with DWI can be useful to discriminate between bone plasmacytoma and bone metastasis in the extremities.