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.     

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.     

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.     

Percutaneous thermal ablation of sacral metastases: Assessment of pain relief and local tumor control

PurposeTo retrospectively report on safety, pain relief and local tumor control achieved with percutaneous ablation of sacral bone metastases.Materials and methodsFrom February 2009 to June 2020, 23 consecutive patients (12 women and 11 men; mean age, 60 ± 8 [SD] years; median, 60; range: 48-80 years) with 23 sacral metastases underwent radiofrequency (RFA) or cryo-ablation (CA), with palliative or curative intent at our institution. Patients’ demographics and data pertaining to treated metastases, procedure-related variables, safety, and clinical evolution following ablation were collected and analyzed. Pain was assessed with numerical pain rating scale (NPRS).ResultsSixteen (70%) patients were treated with palliative and 7 (30%) with curative intent. Mean tumor diameter was 38 ± 19 (SD) mm (median, 36; range: 11-76). External radiation therapy had been performed on five metastases (5/23; 22%) prior to ablation. RFA was used in 9 (39%) metastases and CA in the remaining 14 (61%). Thermo-protective measures and adjuvant bone consolidation were used whilst treating 20 (87%) and 8 (35%) metastases, respectively. Five (22%) minor complications were recorded. At mean 31 ± 21 (SD) (median, 32; range: 2-70) months follow-up mean NPRS was 2 ± 2 (SD) (median, 1; range: 0–6) vs. 5 ± 1 (median, 5; range: 4–8; P < 0.001) at the baseline. Three metastases out of 7 (43%) undergoing curative ablation showed local progression at mean 4 ± 4 (SD) (median, 2; range: 1-8) months follow-up.ConclusionPercutaneous ablation of sacral metastases is safe and results in significant long-lasting pain relief. Local tumor control seems sub-optimal; however, further investigations are needed to confirm these findings due to paucity of data.     

Percutaneous ablation of obscure hypovascular liver tumours in challenging locations using arterial CT-portography guidance

PurposeThe purpose of this study was to evaluate the feasibility, safety and efficacy of percutaneous ablation (PA) of obscure hypovascular liver tumors in challenging locations using arterial CT-portography (ACP) guidance.Materials and methodsA total of 26 patients with a total of 28 obscure, hypovascular malignant liver tumors were included. There were 18 men and 6 women with a mean age of 58 ± 14 (SD) years (range: 37–75 years). The tumors had a mean diameter of 14 ± 10 (SD) mm (range: 7–24 mm) and were intrahepatic cholangiocarcinoma (4/28; 14%), liver metastases from colon cancer (18/28; 64%), corticosurrenaloma (3/28; 11%) or liver metastases from breast cancer (3/28; 11%). All tumors were in challenging locations including subcapsular (14/28; 50%), liver dome (9/28; 32%) or perihilar (5/28; 18%) locations. A total of 28 PA (12 radiofrequency ablations, 11 microwave ablations and 5 irreversible electroporations) procedures were performed under ACP guidance.ResultsA total of 67 needles [mean: 2.5 ± 1.5 (SD); range: 1–5] were inserted under ACP guidance, with a 100% technical success rate for PA. Median total effective dose was 26.5 mSv (IQR: 19.1, 32.2 mSv). Two complications were encountered (pneumothorax; one abscess both with full recovery), yielding a complication rate of 7%. No significant change in mean creatinine clearance was observed (80.5 mL/min at baseline and 85.3 mL/min at day 7; P = 0.8). Post-treatment evaluation of the ablation zone was overestimated on ACP compared with conventional CT examination in 3/28 tumors (11%). After a median follow-up of 20 months (range: 12–35 months), local tumor progression was observed in 2/28 tumours (7%).ConclusionACP guidance is feasible and allows safe and effective PA of obscure hypo-attenuating liver tumors in challenging locations without damaging the renal function and with acceptable radiation exposure. Post-treatment assessment should be performed using conventional CT or MRI to avoid size overestimation of the ablation zone.     

Association between intravesical prostatic protrusion and clinical outcomes in prostatic artery embolization

PurposeTo evaluate the influence of intravesical prostatic protrusion (IPP) on clinical outcomes after prostatic artery embolization (PAE) in patients with lower urinary tract symptoms due to benign prostatic hyperplasia.Materials and methodsAll consecutive patients who underwent PAE for lower urinary tract symptoms between January 2017 and January 2019 were retrospectively included. IPP was evaluated on pre-treatment magnetic resonance imaging examination and symptoms were assessed at follow-up consultations using the international prostate symptom score (IPSS) and quality of life (QOL) questionnaire. IPPs were classified as grade 1 (< 5 mm), grade 2 (5–10 mm), or grade 3 (> 10 mm).ResultsA total of 160 consecutive men (mean age 65 ± 7.8 [SD] years; range: 45–89 years), underwent PAE. The mean IPSS was 21 ± 7.3 (SD) (range: 5–35) and prostate volume 87 ± 38 (SD) mL (range: 30–200 mL). The IPP grade was 1 for 28 (28/160; 18%), 2 for 52 (52/160; 33%), and 3 for 80 (80/160; 50%) patients. There were no significant differences in IPSS at baseline between the three IPP grades. Patients with severe (grade 3) IPP had a significantly higher reduction in IPSS than those with non-severe IPP (grade 1 or 2), with estimated mean reductions of 12 ± 2.5 (SD) (range: ?4–28) and 8.3 ± 1.9 (SD) (range: ?8–21) (P = 0.02), respectively. The mean reduction in the QOL score was 3.0 for grade 3 and 2.0 for grade 1 or 2 IPP (P = 0.02).ConclusionsThe degree of IPP does not limit the efficacy of PAE in patients with lower urinary tract symptoms due to benign prostatic hyperplasia.     

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.     

Effectiveness of CT-guided epidural infiltration of steroids and local anesthetics for acute and chronic herpes zoster neuralgia

PurposeThe purpose of this study was to evaluate the effectiveness and complication rate of computed tomography (CT)-guided epidural injection of steroids and local anesthetics for pain relief in patients with neuralgia due to acute or chronic herpes zoster (HZ).Materials and methodsA prospective study was conducted from April 2017 to February 2019 including patients with HZ neuralgia (HZN) at any stage (acute or chronic, the latter being defined as pain lasting more than 3 months and also called post herpetic neuralgia [PHN]). The sensory ganglion of the affected dermatome and/or the affected sensory nerve was targeted under CT-guidance and local injection of a mixture of two vials of methylprednisolone 40 mg/mL and 2 mL of Lidocaine 1% was performed. Using a visual analogue scale (VAS, 0 to 10), pain was assessed prior to the procedure, and at day 7, 1 month, 3 months and 6 months. Adverse effects were graded according to the Society of Interventional Radiology classification.ResultsTwenty patients were included. There were 9 men and 11 women with a mean age of 67 ± 13.9 (SD) years (range: 27–83 years). Of these, 14 patients had acute HZN and 6 had PHN. Mean VAS at baseline was 8.1 ± 1.2 (SD) (range: 6–10) with significant decrease (P < 0.0001) at day 7 (3.4 ± 3.2 [SD]; range: 0–10), day 30 (3.4 ± 3.2 [SD]; range: 0–9), day 90 (2.9 ± 3.2 [SD]; range: 0–9), and day 180 (2.5 ± 3.1 [SD]; range: 0–9). Infiltrations were significantly more effective on acute HZN than on PHN (P < 0.001) and required significantly fewer infiltrations for pain relef (P = 0.002). Only one grade A adverse event was reported.ConclusionEpidural injection of a mixture of steroids and local anesthetics under CT-guidance is effective on HZN with a persisting effect over 6 months.     

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.     

Synthetic MRI is not yet ready for morphologic and functional assessment of patellar cartilage at 1.5 Tesla

PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences.     

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.     

First intention vertebroplasty in fractures within an ankylosed thoracolumbar spinal segment

PurposeTo evaluate the outcome of percutaneous vertebral cementoplasty (PVC) as the first-line treatment for traumatic thoracolumbar fractures within an ankylosed spinal segment.Materials and methodsThirty-one patients (15 men, 16 women; mean age: 79.2 ± 11 [SD] years; age range: 66–95 years) with thoracolumbar fractures within an ankylosed spine segment without neurological impairment treated with PVC were retrospectively evaluated. All patients were controlled at six weeks and one year after PVC. Ankylosing conditions, fractures sites and types, radiological consolidation, spinal complications were assessed. Anterior/posterior vertebral height ratios were measured before and after PVC. Postoperative pain relief and treatment success (radiological fracture consolidation) rates were considered.ResultsThe 31 patients had a total of 39 fractures (19 stable [49%], 20 unstable [51%]) treated with PVC. Primary success rate of PVC (initial fracture consolidation without complication) was 61% (19/31). Seven patients (7/31; 23%) exhibited new fractures, and the secondary success rate of PVC (global fracture consolidation one year after repeat PVC) was 87% (34/39). Global consolidation rates of unstable fractures were 85% (17/20) of treated levels. Pain score was null in 84% patients (26/31) one year after PVC. There were no significant differences between pre-PVC (0.62 ± 0.18 [SD]; range: 0.22–0.88) and post-PVC (0.60 ± 0.18 [SD]; range: 0.35–0.88) vertebral height ratios (P = 0.94).ConclusionPVC conveys a high overall success rate and effectively controls pain in patients with vertebral fractures within ankylosed spine segments.     

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.     

Discriminating between bronchiolar adenoma,adenocarcinoma in situ and minimally invasive adenocarcinoma of the lung with CT

PurposeTo identify computed tomography (CT) features that may help distinguish bronchiolar adenoma (BA) from lung adenocarcinomas in situ (AIS) and minimally invasive adenocarcinomas (MIA) among lung lesions presenting as ground-glass nodules (GGNs).Materials and methodsA total of 140 patients with GGNs confirmed by surgery and pathology, were reviewed retrospectively. There were 68 men and 72 women with a mean age of 64.3 ± 8.9 (SD) years (range: 31 – 85 years). The CT features of BA, AIS, and MIA were analyzed and compared. CT features, including percentage of solid component, maximum diameter of solid component, lesion density, location, margin, shape, pseudo-cavitation, calcification, ill-defined peripheral opacity, and air bronchogram, were analyzed using multivariate logistic regression and receiver operating characteristic curves.ResultsThere were 11/140 (7.9%) patients with BA (mean age, 67.7 ± 7.5 [SD]; range 45 – 77 years), 63/140 (45.0%) patients with AIS (mean age, 62.5 ± 8.6 [SD]; range 36 – 69 years) and 66/140 (47.1%) patients with MIA (mean age, 63.5 ± 7.9 [SD]; range 35 – 72 years). By comparison with AIS and MIA, significantly different CT features of BA included tumor size, solid component diameters, low CT attenuation of the ground-glass component, irregular shape, ill-defined peripheral opacity, pseudo-cavitation, and abnormal pulmonary vein. Ill-defined peripheral opacity (odds ratio, 1.060; 95% confidence interval [CI]: 1.020 – 1.380) and pseudo-cavitation (odds ratio, 1.236; 95% CI: 1.070 – 1.565) were variables independently associated with the diagnosis of BA.ConclusionCT provides morphological features that allow differentiating between BA and AIS-MIA among lung lesions presenting as GGNs.     

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.     

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.     

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.     

New image quality and dose reduction technique for pediatric digital radiography

PurposeThe purpose of this study was to test a new post-processing and denoising engine for patient dose reduction while maintaining diagnostic image quality (IQ) in pediatric digital radiography (DR).Materials and methodsPediatric DR images of the thorax, pelvis, abdomen and spine obtained in 174 patients (102 males, 72 females; mean age, 2 ± 1.8 [SD] years; age range: 6 months–9 years) were retrieved. Artificial noise was added to the images to simulate acquisitions at 50%, 32% and 12.5% of the routine dose levels. A total of 696 images corresponding to four dose levels were post-processed using S-Vue? and further blindly scored by three pediatric radiologists using a scoring grid of 4–6 criteria specifically defined per anatomical area. The mean score was assessed for each area and weight class (5–15 and 15–30 kg) and compared across the simulated low dose images. Paired Wilcoxon test was used with a threshold difference of 0.5 (half a criterion) between scores to highlight a significant reduction in image quality. Inter-rater reliability was assessed using intraclass correlation coefficient (ICC).ResultsOnly the 50% reduced dose images showed non-inferiority when compared to routine images for all of areas and weight classes (P < 0.01). Very good inter-rater reliability of the overall scores was observed for the pelvis in the 5–15 kg weight class (ICC = 0.85) for images at full dose, 50% and 32% reduced dose. For the remaining areas (thorax, abdomen and spine) and weight classes, inter-rater reliability was moderate (ICC: 0.3–0.6).ConclusionS-Vue? post-processing software allows a two-fold radiation dose reduction while maintaining satisfactory IQ in pediatric DR.     

CT-guided infiltration of greater occipital nerve for refractory craniofacial pain syndromes other than occipital neuralgia

PurposeThe purpose of this study was to evaluate the effectiveness of computed tomography (CT)-guided infiltration of greater occipital nerve (GON) for the treatment of refractory craniofacial pain syndromes other than occipital neuralgia.Materials and methodsFifty-six patients suffering from refractory craniofacial pain syndromes were included between 2011 and 2017. There were 33 women and 23 men with a mean age of 50.7 years ± 13.1 (SD) (range: 27–74 years). CT-guided infiltration was performed at the intermediate site of the GON with local anesthetics and cortivazol. Twenty-six (26/56; 46%) patients suffered from chronic migraine, 14 (14/56; 25%) from trigeminal neuralgia and 16 (16/56; 29%) from cluster headaches. Clinical success at 1, 3, and 6 months was defined by a decrease of at least 50% of pain as assessed using visual analog scale (VAS).ResultsMean overall VAS score before infiltration was 8.7 ± 1.3 (SD) (range: 6 - 10). Mean overall VAS scores after infiltration were 2.3 ± 3 (SD) (range: 0 - 10) (P < 0.01) at one month, 3.5 ± 3.3 (SD) (range: 0 - 10) (P < 0.01) at three months and 7.6 ± 1.3 (SD) (range: 1–10) (P < 0.01) at six months. After infiltration, clinical success was achieved in 44 patients (44/56; 78.5%) at 1 month, 37 patients (37/56; 66%) at 3 months and 13 patients (13/56; 23%) at 6 months. Clinical success according to the clinical presentation were as follows: 88% (23/26) at one month, 73% (19/26) at 3 months, and 23% (6/26) at 6 months in patients with chronic migraine, 81% (13/16), 69% (11/16) and 31% (5/16) in those with cluster headaches and 57% (8/14), 50% (7/14) and 14% (2/14) in those with trigeminal neuralgia. No major complications due to CT-guided GON infiltration were reported in any patient.ConclusionCT-guided infiltration at the intermediate site of the GON appears as an effective treatment of craniofacial pain syndromes especially in patients with chronic migraine and those with cluster headaches.