Three-dimensional Distribution of Muscle and Adipose Tissue of the Thigh at CT: Association with Acute Hip Fracture

Purpose To evaluate determinants of hip fracture by assessing soft-tissue composition of the upper thigh at CT. Materials and Methods In this retrospective analysis of prospectively collected data, CT studies in 55 female control participants (mean age, 73.1 years ± 9.3 [standard deviation]) were compared with those in 40 female patients (mean age, 80.2 years ± 11.0) with acute hip fractures. Eighty-seven descriptors of the soft-tissue composition were determined. A multivariable best subsets analysis was used to extract parameters best associated with hip fracture. Results were adjusted for age, height, and weight. Results of soft-tissue parameters were compared with bone mineral density (BMD) and cortical bone thickness. Areas under the receiver operating characteristic curve (AUCs) adjusted for multiple comparisons were determined to discriminate fracture. Results The hip fracture group was characterized by lower BMD, lower cortical thickness, lower relative adipose tissue volume of the upper thigh, and higher extramyocellular lipid (EML) surface density. The relative volume of adipose tissue combined with EML surface density (model S1) was associated with hip fracture (AUC, 0.85; 95% confidence interval [CI]: 0.78, 0.93), as well as trochanteric trabecular BMD combined with neck cortical thickness (model B2) (AUC, 0.84; 95% CI: 0.75, 0.92). The model including all four parameters provided significantly better (P < .01) discrimination (AUC, 0.92; 95% CI: 0.86, 0.97) than model S1 or B2. Conclusion In addition to bone mineral density and geometry of the proximal femur, the amount of adipose tissue of the upper thigh and the distribution of the adipocytes in the muscles are significantly associated with acute hip fracture at CT. © RSNA, 2018 Online supplemental material is available for this article.

Role of dual-energy CT in the diagnosis and follow-up of gout: systematic analysis of the literature

The aim of this systematic review was to determine the potential role of dual-energy CT in the diagnosis and follow-up of gout with regard to the Outcome Measures in Rheumatology (OMERACT) filter. A systematic analysis of the literature was conducted using the MEDLINE and Cochrane databases and published abstracts of international congresses, according to the criteria of the OMERACT filter: feasibility, reproducibility, validity versus laboratory (serum urate, MSU synovial fluid aspirate) and other imaging modalities for gout, and its sensitivity to change in patients on urate lowering therapy (ULT). Thirty-two articles were found representing a total of 1502 patients. The data on feasibility showed that the examination took little time and involved low levels of radiation but had current limited availability. Intra- and inter-observer reproducibility was excellent, with intra-class correlation coefficients > 0.9. Validity in comparison with polarized-light microscopy showed good sensitivity and specificity (> 80%). The diagnostic performance was better than that of radiography and conventional CT-scan and at least equivalent to that of ultrasonography. The sensitivity to change varied with effect sizes from 0.05 (low) to 1.24 (high) for decrease in the tophus volume following different ULT in gout patients. Dual-energy CT-scan is a reproducible and accurate imaging modality for the diagnosis of gout, particularly for tophaceous gout (intra- or extra-articular). It can become a second-line imaging modality of choice in cases of diagnostic doubt, such as ultrasonography. Its role remains uncertain in the follow-up of gout patients treated with ULT and needs further clarification.

Linear relationship between lateralization of the bicipital groove and humeral retroversion and its link with the biepicondylar humeral line. Anatomical study of seventy cadaveric humerus scans

INTRODUCTION

Morphological studies of the humerus have shown that the position of the bicipital groove varies with the individual and the retroversion of the humeral head. Depending on the authors, these two parameters are independent or associated. This study evaluated the relationship between the humeral head axis and its retroversion and the bicipital groove relative to the humeral biepicondylar line.

MATERIALS AND METHODS

Seventy cadaveric humeri were scanned to obtain 3D reconstructions. Views of the 3D reconstruction from above showed the bicondylar line, the bicipital groove and the humeral head on a single image. After measuring the humeral retroversion angle and the bicipital groove angle relative to the bicondylar line, we assessed the relationship between these two angles with Pearson's correlation coefficient.

RESULTS

Pearson's correlation coefficient indicated a significant linear correlation between the angle of the groove and the angle of humeral retroversion based on the 70 cadaveric humeral bones (the p-value was 7.5^10-7, the correlation coefficient was -0.5515, and the 95% confidence interval was (-0.6962; -0.3636)). Our study thus demonstrates that the less lateralized the bicipital groove is, the greater the humeral retroversion will be.

CONCLUSION

We demonstrated a linear relationship between humeral head retroversion and bicipital groove lateralization. Within our reliability interval, this relationship can be used in clinical practice to evaluate retroversion without resorting to CT of the entire humerus.

Selective arterial embolization of symptomatic and asymptomatic renal angiomyolipomas: a retrospective study of safety, outcomes and tumor size reduction

BACKGROUND

Angiomyolipoma (AML) is the most common renal benign tumor. Treatment should be considered for symptomatic patients or for those at risk for complications, especially retroperitoneal bleeding which is correlated to tumor size, grade of the angiogenic component and to the presence of tuberous sclerosis complex (TSC). This study reports our single-center experience with the use of selective arterial embolization (SAE) in the management of symptomatic and asymptomatic renal AMLs.

METHODS

In this retrospective mono-centric study, all demographic and imaging data, medical records, angiographic features, outpatient charts and follow-up visits of patients who underwent prophylactic or emergency SAE for AMLs between January 2005 and July 2016 were reviewed. Tumor size and treatment outcomes were assessed at baseline and after the procedure during follow-up. Computed tomography (CT), magnetic resonance imaging (MRI) or ultrasonography was used to evaluate AML shrinkage. Renal function was measured pre- and post-procedure.

RESULTS

Twenty-three patients (18 females, 5 males; median age, 45 years; range, 19-85 years) who underwent SAE either to treat bleeding AML (n=6) or as a prophylactic treatment (n=17) were included. Overall, 34 AMLs were embolized. TSC status was confirmed for 6 patients. Immediate technical success rate was 96% and 4 patients benefitted from an additional procedure. Major complications occurred in 3 patients and minor post-embolization syndrome (PES) in 14 patients. The mean AML size reduction rate was 26.2% after a mean follow-up was 20.5 months (range, 0.5-56 months), and only non-TSC status was significantly associated with better shrinkage of tumor (P=0.022). Intralesional aneurysms were significantly more frequent in patients with hemorrhagic presentation (P=0.008). There was no change in mean creatinine level after SAE.

CONCLUSIONS

SAE is a safe and effective technique to manage renal AMLs as a preventive treatment as well as in emergency setting, with significant reduction in tumor size during follow-up. A multidisciplinary approach remains fundamental, especially for TSC patients. In addition to size, the presence of intralesional aneurysms should be considered in any prophylactic treatment decision.

Parascapular mass revealing primary tuberculosis of the posterior arch

We report the case of a parascapular abscess revealing primary tuberculosis of the posterior arch in a 31-year-old man. Sectional imaging is essential in order to detect the different lesions of this atypical spinal tuberculosis as osteolysis of the posterior arch extendible to vertebral body, osteocondensation, epidural extension which is common in this location, and high specificity of a zygapophysial, costo-vertebral or transverse arthritis.

Endovascular stent placement for chronic post-thrombotic symptomatic ilio-femoral venous obstructive lesions: a single-center study of safety, efficacy and quality-of-life improvement

BACKGROUND

Post-thrombotic syndrome (PTS) is a frequent complication of deep vein thrombosis (DVT) despite adequate treatment. Venous angioplasty and stent placement has been progressively used to restore and maintain venous patency in PTS patients. This study reports our single-center experience with the use of endovascular treatment for chronic post-thrombotic symptomatic ilio-femoral venous obstructive lesions.

METHODS

A prospective mono-centric observational cohort study of PTS patients with chronic symptomatic ilio-femoral venous obstructive lesions referred for endovascular treatment was conducted from March 2012 to April 2016. Procedure consisted in recanalization, pre-dilation and self-expandable stenting of stenotic or occluded iliac and/or femoral veins. Severity of PTS, quality-of-life and treatment outcomes were assessed using Villalta scale and Chronic Venous Insufficiency Questionnaire (CIVIQ-20) at baseline and 3 months after the procedure. Imaging follow-up was based on duplex ultrasound (US) and computed tomography (CT).

RESULTS

Twenty-one patients (11 females, 10 males; median age, 41 years; range, 32-60) were included. Recanalization and stenting was successfully accomplished in all prime procedures, 4 patients benefitted from an additional procedure. Immediate technical success rate was 96% considering 25 procedures, performed without any complications. Median follow-up was 18 months (range, 6-30 months) with a 90.5% stent patency rate. Villalta score significantly decreased from baseline compared with 3 months after the procedure [14 (range, 11-22) and 5 (range, 1-10), respectively, P<0.0001], showing a significant decrease in the severity of PTS. CIVIQ-20 score significantly decreased from baseline compared with 3 months after stenting [48.5 (range, 39-73) and 26.5 (range, 21-45), respectively, P<0.0001] thus showing a significant improvement of quality-of-life. Post-procedural CIVIQ-20 score was significantly associated with Villalta score (95% CI, 1.53-2.95; P<0.0001).

CONCLUSIONS

Our results confirm the high clinical success rate and safety of endovascular PTS treatment and highlight the significant impact of stenting on the quality of life of patients with chronic symptomatic ilio-femoral venous obstructive lesions.

Ethylene-vinyl alcohol copolymer (Onyx(®)) transarterial embolization for post-traumatic high-flow priapism

We report a case of high-flow priapism treated successfully with superselective embolization of the cavernous artery. A 16-year-old male developed post-traumatic priapism subsequent to a fall causing blunt perineal trauma. He presented to our hospital four days after trauma. Immediately after the injury, he suffered painless sustained incomplete erection. High-flow priapism was diagnosed on the basis of color doppler ultrasonography findings. Computed tomography scan showed a high-flow arterio-venous fistula with feeders from branches of the right internal iliac artery. Selective arteriography of the right internal pudendal artery demonstrated an arterio-cavernous fistula. The fistula was superselectively embolized with ethylene-vinyl alcohol copolymer (Onyx(®)) liquid agent and disappeared completely. Improvement was noted, with significant detumescence on table. This was later confirmed on repeat color Doppler imaging. At follow-up 3 months later, he had normal erectile function. To our knowledge, transarterial embolization of high-flow priapism with Onyx(®) has never been reported and appears to be a safe and effective treatment for managing patients with such a condition.

Endovascular management of a large aneurysm of the superior vena cava involving internal thoracic vein with remodeling technique

We report a case describing endovascular treatment of a large aneurysm of the superior vena cava involving internal thoracic vein. The goal of this case report is to highlight the contributing role of embolization with remodeling technique in such an exceptional condition.

Prediction of Hip Failure Load: In Vitro Study of 80 Femurs Using Three Imaging Methods and Finite Element Models-The European Fracture Study (EFFECT)

Purpose To evaluate the performance of three imaging methods (radiography, dual-energy x-ray absorptiometry [DXA], and quantitative computed tomography [CT]) and that of a numerical analysis with finite element modeling (FEM) in the prediction of failure load of the proximal femur and to identify the best densitometric or geometric predictors of hip failure load. Materials and Methods Institutional review board approval was obtained. A total of 40 pairs of excised cadaver femurs (mean patient age at time of death, 82 years ± 12 [standard deviation]) were examined with (a) radiography to measure geometric parameters (lengths, angles, and cortical thicknesses), (b) DXA (reference standard) to determine areal bone mineral densities (BMDs), and (c) quantitative CT with dedicated three-dimensional analysis software to determine volumetric BMDs and geometric parameters (neck axis length, cortical thicknesses, volumes, and moments of inertia), and (d) quantitative CT-based FEM to calculate a numerical value of failure load. The 80 femurs were fractured via mechanical testing, with random assignment of one femur from each pair to the single-limb stance configuration (hereafter, stance configuration) and assignment of the paired femur to the sideways fall configuration (hereafter, side configuration). Descriptive statistics, univariate correlations, and stepwise regression models were obtained for each imaging method and for FEM to enable us to predict failure load in both configurations. Results Statistics reported are for stance and side configurations, respectively. For radiography, the strongest correlation with mechanical failure load was obtained by using a geometric parameter combined with a cortical thickness (r(2) = 0.66, P < .001; r(2) = 0.65, P < .001). For DXA, the strongest correlation with mechanical failure load was obtained by using total BMD (r(2) = 0.73, P < .001) and trochanteric BMD (r(2) = 0.80, P < .001). For quantitative CT, in both configurations, the best model combined volumetric BMD and a moment of inertia (r(2) = 0.78, P < .001; r(2) = 0.85, P < .001). FEM explained 87% (P < .001) and 83% (P < .001) of bone strength, respectively. By combining (a) radiography and DXA and (b) quantitative CT and DXA, correlations with mechanical failure load increased to 0.82 (P < .001) and 0.84 (P < .001), respectively, for radiography and DXA and to 0.80 (P < .001) and 0.86 (P < .001) , respectively, for quantitative CT and DXA. Conclusion Quantitative CT-based FEM was the best method with which to predict the experimental failure load; however, combining quantitative CT and DXA yielded a performance as good as that attained with FEM. The quantitative CT DXA combination may be easier to use in fracture prediction, provided standardized software is developed. These findings also highlight the major influence on femoral failure load, particularly in the trochanteric region, of a densitometric parameter combined with a geometric parameter. (©) RSNA, 2016 Online supplemental material is available for this article.

Preoperative portal vein embolization in liver cancer: indications, techniques and outcomes

Postoperative liver failure is a severe complication of major hepatectomies, in particular in patients with a chronic underlying liver disease. Portal vein embolization (PVE) is an approach that is gaining increasing acceptance in the preoperative treatment of selected patients prior to major hepatic resection. Induction of selective hypertrophy of the non-diseased portion of the liver with PVE in patients with either primary or secondary hepatobiliary, malignancy with small estimated future liver remnants (FLR) may result in fewer complications and shorter hospital stays following resection. Additionally, PVE performed in patients initially considered unsuitable for resection due to lack of sufficient remaining normal parenchyma may add to the pool of candidates for surgical treatment. A thorough knowledge of hepatic segmentation and portal venous anatomy is essential before performing PVE. In addition, the indications and contraindications for PVE, the methods for assessing hepatic lobar hypertrophy, the means of determining optimal timing of resection, and the possible complications of PVE need to be fully understood before undertaking the procedure. Technique may vary among operators, but cyanoacrylate glue seems to be the best embolic agent with the highest expected rate of liver regeneration for PVE. The procedure is usually indicated when the remnant liver accounts for less than 25-40% of the total liver volume. Compensatory hypertrophy of the non-embolized segments is maximal during the first 2 weeks and persists, although to a lesser extent during approximately 6 weeks. Liver resection is performed 2 to 6 weeks after embolization. The goal of this article is to discuss the rationale, indications, techniques and outcomes of PVE before major hepatectomy.

Current role of multiparametric magnetic resonance imaging for prostate cancer

Multiparametric magnetic resonance imaging (mp-MRI) has shown promising results in diagnosis, localization, risk stratification and staging of clinically significant prostate cancer, and targeting or guiding prostate biopsy. mp-MRI consists of T2-weighted imaging (T2WI) combined with several functional sequences including diffusion-weighted imaging (DWI), perfusion or dynamic contrast-enhanced imaging (DCEI) and spectroscopic imaging. Recently, mp-MRI has been used to assess prostate cancer aggressiveness and to identify anteriorly located tumors before and during active surveillance. Moreover, recent studies have reported that mp-MRI is a reliable imaging modality for detecting local recurrence after radical prostatectomy or external beam radiation therapy. Because assessment on mp-MRI can be subjective, use of the newly developed standardized reporting Prostate Imaging and Reporting Archiving Data System (PI-RADS) scoring system and education of specialist radiologists are essential for accurate interpretation. This review focuses on the current place of mp-MRI in prostate cancer and its evolving role in the management of prostate cancer.

Impact of systematic ultrasound of the knee on the rheumatologist's clinical decision in patients consulting for knee pain

This clinical practice study aimed to determine whether the results of systematic US in patients with knee pain modified the rheumatologist's choices concerning diagnostic management and therapy. Patients consulting for non-traumatic knee pain, with recent radiography of the knee, were consecutively included over 9 months. After the radio-clinical assessment, the rheumatologist made a principal diagnosis concerning the knee pain and defined the therapeutic management and a complementary imaging strategy if necessary. US of the painful knee was then done in accordance with the reference protocol with the operators blinded to the clinical results. After reading the US report, the rheumatologist re-evaluated his/her diagnostic and therapeutic approach and the complementary exploration strategy. In the 100 patients included (mean age = 62.9 ± 18.5 years, duration of knee pain = 14.4 ± 8.1 months) with a majority of knee osteoarthritis (61 %), the diagnosis was clarified or modified after the US in 31 % of cases (calcium pyrophosphate deposition arthropathy and tendinitis principally), which led to an intensification of therapy in 15 % of cases and a de-escalation in 5 % of cases. These changes mainly concerned injectable treatments. The US of the painful knee resulted in few changes in imaging prescriptions (6 %), and this was not significant for the number of MRIs requested. In real-life practice in rheumatology, systematic US of the knee clarified the initial clinical diagnosis in almost one-third of cases, but did not significantly modify the therapeutic management, which remained symptomatic, and did not reduce the number of other imaging examinations after the initial radio-clinical assessment.

Endovascular management of visceral artery aneurysms: When to watch, when to intervene?

Visceral artery aneurysms (VAA) include splanchnic and renal artery aneurysms. They represent a rare clinical entity, although their detection is rising due to an increased use of cross-sectional imaging. Rupture is the most devastating complication, and is associated with a high morbidity and mortality. In addition, increased percutaneous endovascular interventions have raised the incidence of iatrogenic visceral artery pseudoaneurysms (VAPAs). For this reason, elective repair is preferable in the appropriately chosen patient. Controversy still exists regarding their treatment. Over the past decade, there has been steady increase in the utilization of minimally invasive, non-operative interventions, for vascular aneurysmal disease. All VAAs and VAPAs can technically be fixed by endovascular techniques but that does not mean they should. These catheter-based techniques constitute an excellent approach in the elective setting. However, in the emergent setting it may carry a higher morbidity and mortality. The decision for intervention has to take into account the size and the natural history of the lesion, the risk of rupture, which is high during pregnancy, and the relative risk of surgical or radiological intervention. For splanchnic artery aneurysms, we should recognize that we are not, in reality, well informed about their natural history. For most asymptomatic aneurysms, expectant treatment is acceptable. For large, symptomatic or aneurysms with a high risk of rupture, endovascular treatment has become the first-line therapy. Treatment of VAPAs is always mandatory because of the high risk of rupture. We present our point of view on interventional radiology in the splanchnic arteries, focusing on what has been achieved and the remaining challenges.

Transjugular intrahepatic portosystemic shunt for acute variceal gastrointestinal bleeding: Indications, techniques and outcomes

Acute variceal bleeding is a life-threatening condition that requires a multidisciplinary approach for effective therapy. The transjugular intrahepatic portosystemic shunt (TIPS) procedure is a minimally invasive image-guided intervention used for secondary prevention of bleeding and as salvage therapy in acute bleeding. Emergency TIPS should be considered early in patients with refractory variceal bleeding once medical treatment and endoscopic sclerotherapy fail, before the clinical condition worsens. Furthermore, admission to specialized centers is mandatory in such a setting and regional protocols are essential to be organized effectively. This procedure involves establishment of a direct pathway between the hepatic veins and the portal veins to decompress the portal venous hypertension that is the source of the patient's bleeding. The procedure is technically challenging, especially in critically ill patients, and has a mortality of 30%-50% in the emergency setting, but has an effectiveness greater than 90% in controlling bleeding from gastro-esophageal varices. This review focuses on the role of TIPS in the setting of variceal bleeding, with emphasis on current indications and techniques for TIPS creation, TIPS clinical outcomes, and the role of adjuvant embolization of varices.

Transjugular intrahepatic portosystemic shunt for the management of acute variceal hemorrhage

Acute variceal hemorrhage, a life-threatening condition that requires a multidisciplinary approach for effective therapy, is defined as visible bleeding from an esophageal or gastric varix at the time of endoscopy, the presence of large esophageal varices with recent stigmata of bleeding, or fresh blood visible in the stomach with no other source of bleeding identified. Transfusion of blood products, pharmacological treatments and early endoscopic therapy are often effective; however, if primary hemostasis cannot be obtained or if uncontrollable early rebleeding occurs, transjugular intrahepatic portosystemic shunt (TIPS) is recommended as rescue treatment. The TIPS represents a major advance in the treatment of complications of portal hypertension. Acute variceal hemorrhage that is poorly controlled with endoscopic therapy is generally well controlled with TIPS, which has a 90% to 100% success rate. However, TIPS is associated with a mortality of 30% to 50% in such a setting. Emergency TIPS should be considered early in patients with refractory variceal bleeding once medical treatment and endoscopic sclerotherapy failure, before the clinical condition worsens. Furthermore, admission to specialized centers is mandatory in such a setting and regional protocols are essential to be organized effectively. This review article discusses initial management and then focuses on the specific role of TIPS as a primary therapy to control acute variceal hemorrhage, particularly as a rescue therapy following failure of endoscopic approaches.