Resonant inelastic soft x-ray scattering on LaPt2Si2.

X-ray absorption and resonant inelastic x-ray scattering spectra of LaPt2Si2single crystal at the Si 2pand La 4dedges are presented. The data are interpreted in terms of density functional theory, showing that the Si spectra can be described in terms of Sisanddlocal partial density of states (LPDOS), and the La spectra are due to quasi-atomic local 4fexcitations. Calculations show that Ptd-LPDOS dominates the occupied states, and a sharp localized Lafstate is found in the unoccupied states, in line with the observations.

Arthroscopic Rotator Cuff Repair Augmentation With Autologous Microfragmented Lipoaspirate Tissue Is Safe and Effectively Improves Short-term Clinical and Functional Results: A Prospective Randomized Controlled Trial With 24-Month Follow-up.

BACKGROUND: Autologous microfragmented lipoaspirate tissue has been recently introduced in orthopaedics as an easily available source of nonexpanded adipose-derived mesenchymal stem cells. Autologous microfragmented lipoaspirate tissue is expected to create a suitable microenvironment for tendon repair and regeneration. Rotator cuff tears show a high incidence of rerupture and represent an ideal target for nonexpanded mesenchymal stem cells. PURPOSE: To evaluate the safety and efficacy of autologous lipoaspirate tissue in arthroscopic rotator cuff repair. STUDY DESIGN: Randomized controlled trial; Level of evidence, 2. METHODS: Consecutive patients referring to the investigation center for surgical treatment of magnetic resonance imaging-confirmed degenerative posterosuperior rotator cuff tears were assessed for eligibility. Those who were included were randomized to receive a single-row arthroscopic rotator cuff repair, followed by intraoperative injection of autologous microfragmented adipose tissue processed with an enzyme-free technology (treatment group) or not (control group). Clinical follow-up was conducted at 3, 6, 12, 18, and 24 months; at 18 months after surgery, magnetic resonance imaging of the operated shoulder was obtained to assess tendon integrity and rerupture rate. RESULTS: An overall 177 patients were screened, and 44 (22 per group) completed the 24-month follow-up. A statistically significant difference in favor of the treatment group in terms of Constant-Murley score emerged at the primary endpoint at 6-month follow-up (mean ± SD; control group, 76.66 ± 10.77 points; treatment group, 82.78 ± 7.00 points; P = .0050). No significant differences in clinical outcome measures were encountered at any of the other follow-up points. No significant differences emerged between the groups in terms of rerupture rate, complication rate, and number of adverse events. CONCLUSION: This prospective randomized controlled trial demonstrated that the intraoperative injection of autologous microfragmented adipose tissue is safe and effective in improving short-term clinical and functional results after single-row arthroscopic rotator cuff repair. REGISTRATION: NCT02783352 (ClinicalTrials.gov identifier).

Platelet-Rich Plasma in Arthroscopic Rotator Cuff Repair: Clinical and Radiological Results of a Prospective Randomized Controlled Trial Study at 10-Year Follow-Up.

PURPOSE: The aim of the study is to compare, at 10-year follow-up, the clinical and radiological outcomes of arthroscopic rotator cuff repair with or without the addition of platelet-rich plasma (PRP) over the tendon-bone interface at the end of the surgical procedure. METHODS: Of 53 patients recruited in the study, and randomly divided into 2 groups (PRP = 26; control = 27), 38 were re-evaluated at least 10 years after the index procedure. The clinical evaluation was carried out through: University of California at Los Angeles (UCLA) Shoulder Score, Visual Analogue Scale (VAS), Simple Shoulder Test, Constant-Murley Score (CMS), Single Assessment Numerical Evaluation (SANE), American Shoulder and Elbow Surgeons (ASES) and isometric strength in abduction, forward flexion and external rotation. Musculoskeletal ultrasonography had been used to evaluate the integrity of the repaired cuff. RESULTS: A number of 38 (71%) patients (PRP = 17; control = 21) with a median age of 71 [64.75-76.50] years have been evaluated. Satisfaction at follow-up is high (90%), without statistically significant difference between the two groups. We report good and excellent clinical results in both groups (PRP vs control): CMS (81.62 [72.47-85.75] vs 77.97 [69.52-82.55] points), UCLA (34 [29.00-35.00] vs 33 [29.00-35.00] points), VAS (0.34 [0.00-1.85] vs 0.70 [0.00-2.45] cm). It was not possible to find a statistically significant difference for the variables analyzed, except for ASES and SANE. On average, 37% of the operated patients had a re-rupture at the ultrasound examination, regardless of the treatment group (P = 1.00). Compared with the previous radiological control at the 2-year follow-up, new retears occurred in 6% of the patients who received PRP treatment, whereas in the control group the percentage raises to 14% (P = .61). CONCLUSION: The clinical and radiological outcomes at the 10-year follow-up show a substantial uniformity of results between the 2 groups. The minor differences that had been observed at 2-year follow-up disappeared at long term. Patients' satisfaction is still high 10 years after surgical treatment. LEVEL OF EVIDENCE: Level II, randomized controlled trial, treatment study.

Na-ion mobility in P2-type Na0.5MgxNi0.17-xMn0.83O2 (0 ≤ x ≤ 0.07) from electrochemical and muon spin relaxation studies.

Sodium transition metal oxides with a layered structure are one of the most widely studied cathode materials for Na+-ion batteries. Since the mobility of Na+ in such cathode materials is a key factor that governs the performance of material, electrochemical and muon spin rotation and relaxation techniques are here used to reveal the Na+-ion mobility in a P2-type Na0.5MgxNi0.17-xMn0.83O2 (x = 0, 0.02, 0.05 and 0.07) cathode material. Combining electrochemical techniques such as galvanostatic cycling, cyclic voltammetry, and the galvanostatic intermittent titration technique with µ+SR, we have successfully extracted both self-diffusion and chemical-diffusion under a potential gradient, which are essential to understand the electrode material from an atomic-scale viewpoint. The results indicate that a small amount of Mg substitution has strong effects on the cycling performance and the Na+ mobility. Amongst the tested cathode systems, it was found that the composition with a Mg content of x = 0.02 resulted in the best cycling stability and highest Na+ mobility based on electrochemical and µ+SR results. The current study clearly shows that for developing a new generation of sustainable energy-storage devices, it is crucial to study and understand both the structure as well as dynamics of ions in the material on an atomic level.

Cation Distributions and Magnetic Properties of Ferrispinel MgFeMnO4.

The crystal structure and magnetic properties of the cubic spinel MgFeMnO4 were studied by using a series of in-house techniques along with large-scale neutron diffraction and muon spin rotation spectroscopy in the temperature range between 1.5 and 500 K. The detailed crystal structure is successfully refined by using a cubic spinel structure described by the space group Fd3̅m. Cations within tetrahedral A and octahedral B sites of the spinel were found to be in a disordered state. The extracted fractional site occupancies confirm the presence of antisite defects, which are of importance for the electrochemical performance of MgFeMnO4 and related battery materials. Neutron diffraction and muon spin spectroscopy reveal a ferrimagnetic order below TC = 394.2 K, having a collinear spin arrangement with antiparallel spins at the A and B sites, respectively. Our findings provide new and improved understanding of the fundamental properties of the ferrispinel materials and of their potential applications within future spintronics and battery devices.

Magnetism and ion diffusion in honeycomb layered oxide [Formula: see text].

In the quest for developing novel and efficient batteries, a great interest has been raised for sustainable K-based honeycomb layer oxide materials, both for their application in energy devices as well as for their fundamental material properties. A key issue in the realization of efficient batteries based on such compounds, is to understand the K-ion diffusion mechanism. However, investigation of potassium-ion (K[Formula: see text]) dynamics in materials using e.g. NMR and related techniques has so far been very challenging, due to its inherently weak nuclear magnetic moment, in contrast to other alkali ions such as lithium and sodium. Spin-polarised muons, having a high gyromagnetic ratio, make the muon spin rotation and relaxation ([Formula: see text]SR) technique ideal for probing ions dynamics in these types of energy materials. Here we present a study of the low-temperature magnetic properties as well as K[Formula: see text] dynamics in honeycomb layered oxide material [Formula: see text] using mainly the [Formula: see text]SR technique. Our low-temperature [Formula: see text]SR results together with complementary magnetic susceptibility measurements find an antiferromagnetic transition at [Formula: see text] K. Further [Formula: see text]SR studies performed at higher temperatures reveal that potassium ions (K[Formula: see text]) become mobile above 200 K and the activation energy for the diffusion process is obtained as [Formula: see text] meV. This is the first time that K[Formula: see text] dynamics in potassium-based battery materials has been measured using [Formula: see text]SR. Assisted by high-resolution neutron diffraction, the temperature dependence of the K-ion self diffusion constant is also extracted. Finally our results also reveal that K-ion diffusion occurs predominantly at the surface of the powder particles. This opens future possibilities for potentially improving ion diffusion as well as K-ion battery device performance using nano-structuring and surface coatings of the particles.

Quantifying Diffusion through Interfaces of Lithium-Ion Battery Active Materials.

Detailed understanding of charge diffusion processes in a lithium-ion battery is crucial to enable its systematic improvement. Experimental investigation of diffusion at the interface between active particles and the electrolyte is challenging but warrants investigation as it can introduce resistances that, for example, limit the charge and discharge rates. Here, we show an approach to study diffusion at interfaces using muon spin spectroscopy. By performing measurements on LiFePO4 platelets with different sizes, we determine how diffusion through the LiFePO4 (010) interface differs from that in the center of the particle (i.e., bulk diffusion). We perform ab initio calculations to aid the understanding of the results and show the relevance of our interfacial diffusion measurement to electrochemical performance through cyclic voltammetry measurements. These results indicate that surface engineering can be used to improve the performance of lithium-ion batteries.

Image quality of hip MR arthrography with intra-articular injection of hyaluronic acid versus gadolinium-based contrast agent in patients with femoroacetabular impingement.

OBJECTIVE: To compare image quality of magnetic resonance arthrography (MRA) of the hip with intra-articular injection of high-viscosity hyaluronic acid (HA-MRA) versus Gd-based contrast agent (Gd-MRA) in patients with femoroacetabular impingement (FAI). MATERIALS AND METHODS: Design: single-centre, observational, retrospective, inter-individual, and cross-sectional. FAI patients who underwent HA-MRA (3 mL of high-viscosity HA plus 17 mL of saline) were compared with 37 age- and sex-matched FAI patients who underwent Gd-MRA (20 mL of 2 mmol/L solution of gadopentetate dimeglumine). Two independent blinded radiologists assessed image quality for all sequences (two-dimensional proton density, non-fat-sat axial, fat-sat coronal and sagittal; three-dimensional dual-echo steady state), using a 5-point Likert scale considering separately labrum, cartilage, round ligament, transverse ligament, and capsule. Pearson χ2 and Cohen κ were used. RESULTS: The HA-MRA group was composed of 37 patients (23 males, 14 females; median age 38 years), the Gd-MRA group of 37 patients (21 males, 16 females; median age 38 years), without significant difference for age (p = 0.937) and sex (p = 0.636). Image quality did not differ between the two readers for any structure: labrum (p ≥ 0.340), cartilage (p ≥ 0.198), round ligament (p ≥ 0.255), transverse ligament (p ≥ 0.806), and capsule (p ≥ 0.314). Inter-reader agreement (κ) ranged from 0.785 to 1.000. CONCLUSIONS: HA-MRA provided an image quality not significantly different from that of Gd-MRA. This may open the possibility of combining MRA and viscosupplementation in one single procedure.

MRI-Derived Biomarkers Related to Sarcopenia: A Systematic Review.

BACKGROUND: MRI allows quantitatively assessing muscle quantity and quality. PURPOSE: To summarize the role of MRI as a noninvasive technique for the identification of in vivo surrogate biomarker of sarcopenia. STUDY TYPE: Systematic review. POPULATION: In April 2019, a systematic literature search (Medline/EMBASE) was performed to identify articles on the topic at issue. FIELD STRENGTH/SEQUENCE: No field strength or sequence restrictions. ASSESSMENT: After a literature search, study design, aim, sample size, demographics, magnetic field strength, imaged body region, MRI sequences, and imaging biomarker were extracted. STATISTICAL TESTS: Data are presented as frequencies and percentages. RESULTS: From 69 records identified through search query, 18 articles matched the inclusion criteria. All articles were published from 2012 and had a mainly prospective design (14/18, 78%). Sample size ranged from 9 to 284 subjects, for a total of 1706 enrolled subjects. Healthy subjects were enrolled or retrospectively selected in 8/18 (44%) articles, corresponding to 658 (39%) healthy subjects. Magnetic field strength was 1.5 or 3T in 14/18 (78%) studies. The most analyzed body regions were the thigh (7/18, 39%) and the trunk (6/18, 33%). Stratifying studies according to their aim, 13/18 (72%) studies focused on muscle quality and quantity, 3/18 (17%) studies on outcome prediction, and 2/18 articles (11%) addressed both aims. A wide set of MRI biomarkers have been proposed. Muscle cross-sectional area was the most used for muscle quantity estimation, while quantitative biomarkers of muscle fat content or fiber architecture were proposed to assess muscle quality. DATA CONCLUSION: The proposed biomarkers were assessed using different MRI sequences for different body regions in different subjects/patient cohorts, pointing out a lack of standardization on this topic. Future studies should test and compare the performance of proposed MRI biomarkers for sarcopenia characterization and quantification using a standardized experimental setup. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:1117-1127.

Evaluation of muscle tears in professional athletes using diffusion-weighted imaging and apparent diffusion coefficient: preliminary results.

PURPOSE: Many studies have evaluated the role of DWI in musculoskeletal diseases but less is known on muscle tears. Especially for professional athletes, muscle injuries are responsible for large time lost. The aim of this study was to investigate on potential relationship between the muscle tear degree and the diffusion characteristics. METHODS: In this retrospective study, patients signed a comprehensive consent form according to Good Clinical Practice guidelines before proceeding with all examinations. It satisfied all the requirements of the Declaration of Helsinki and the Italian national law for the protection of personal data. We have analyzed 38 professional athletes (36 males; mean age±standard deviation 27±8 years) with a muscle tear. They were 26 football and 12 athletics players, with clinically suspected injuries of the lower limbs muscles. All of patients underwent a 1.5-T MRI with standard protocol (STIR, TSE T2, SE T1, PD T2, PD fat sat T2) plus the DWI sequences with 0, 400 and 800 B-values (s/mm2). Per each B value, an experienced radiologist measured the signal intensity (SI, in arbitrary units [au]) using a region of interest (ROI) placed within the tear on DWI images. SI drop off at the third B value was calculated referred to the first B value. Similarly, ADC was measured using the ADC map in a small ROI within the tear. Bivariate associations were evaluated using the Student t test. Logistic regression was performed using the tear degree as dependent variable. Data were given as mean±standard deviation. RESULTS: According the Muller-Wohlfarth classification, the 38 muscle tears were classified in type 3a in 22/38 cases and 3b in 16/38 cases. At bivariate analysis, 3a-tears had a SI at the third B value (24±9 au) lower (P=0.003) than that of 3b-tears (34±9 au). Similarly, 3a-tears had a SI drop off (73±10%) lower (P=0.008) than that of 3b-tears (82±9%). ADC was not significantly associated to tear degree (P=0.093). At regression analysis, SI at the third B value was the only independent predictor of the tear degree (P=0.032), while the SI drop off was borderline significant (P=0.070). CONCLUSION: This preliminary data showed a positive correlation between the degree of muscle tears and the SI at the third B-value. Compared to 3a- tears, 3b-tears tend to show higher SI and a higher SI drop off.

Long-term Results of Arthroscopic Rotator Cuff Repair: Initial Tear Size Matters: A Prospective Study on Clinical and Radiological Results at a Minimum Follow-up of 10 Years.

BACKGROUND: Arthroscopic techniques are now considered the gold standard for treatment of most rotator cuff (RC) tears; however, no consensus exists on the maintenance of results over time, and long-term follow-up data have been reported for few cohorts of patients. PURPOSE: To present the long-term results associated with the arthroscopic treatment of RC tears and to evaluate associations between preoperative factors and RC integrity at final follow-up. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 169 patients were contacted at least 10 years after arthroscopic RC surgery and were invited to a clinical evaluation. Information on preoperative conditions, tear size, subjective satisfaction, and functional scores was collected; isometric strength and range of motion were also measured; and each patient underwent an ultrasound examination to evaluate supraspinatus integrity and a shoulder radiograph to evaluate osteoarthritis. RESULTS: A total of 149 patients (88.2% of the eligible patients) were available for a complete telephonic interview, and 102 patients were available for the final evaluation. Ultrasound revealed an intact supraspinatus in 54 patients (53.47%). By adding the 10 patients who underwent revision surgery to the nonintact group, this percentage would drop to 48.65%. Tear size was associated with supraspinatus integrity in univariate analysis (hazard ratio, 3.04; 95% CI, 1.63-5.69; P = .001) and multivariable analysis (hazard ratio, 2.18; 95% CI, 1.03-4.62; P = .04). However, no significant differences were encountered in the subjective and functional scores collected, with the exception of the Constant-Murley Score, which was significantly higher in patients with smaller tears at the index procedure. Strength testing also revealed significantly superior abduction and flexion strength in this group, and radiographs showed a significantly higher acromion-humeral distance and lower grades of osteoarthritis. Patients with an intact supraspinatus at final follow-up showed superior results in all functional scores, greater satisfaction, superior abduction and flexion strength, higher acromion-humeral distance, and lower grades of osteoarthritis. CONCLUSION: RC tear size at the time of surgery significantly affects supraspinatus integrity at a minimum follow-up of 10 years. However, a larger tear is not associated with an inferior subjective result, although it negatively influences abduction and flexion strength, range of motion, and osteoarthritis progression. Intraoperative efforts to obtain a durable RC repair are encouraged, since supraspinatus integrity at final follow-up influences clinical and functional outcomes, patient satisfaction, and osteoarthritis progression.

Magnetic phase diagram of K2Cr8O16 clarified by high-pressure muon spin spectroscopy.

The K2Cr8O16 compound belongs to a series of quasi-1D compounds with intriguing magnetic properties that are stabilized through a high-pressure synthesis technique. In this study, a muon spin rotation, relaxation and resonance (µ+SR) technique is used to investigate the pressure dependent magnetic properties up to 25 kbar. µ+SR allows for measurements in true zero applied field and hereby access the true intrinsic material properties. As a result, a refined temperature/pressure phase diagram is presented revealing a novel low temperature/high pressure (pC1 = 21 kbar) transition from a ferromagnetic insulating to a high-pressure antiferromagnetic insulator. Finally, the current study also indicates the possible presence of a quantum critical point at pC2 ~ 33 kbar where the magnetic order in K2Cr8O16 is expected to be fully suppressed even at T = 0 K.

Acute and overuse elbow trauma: radio-orthopaedics overview.

The correct management of acute, subacute and overuse-related elbow pathologies represents a challenging diagnostic and therapeutic problem. While major trauma frequently requires a rapid surgical intervention, subluxation and minor trauma allow taking more time for diagnostics and planning the correct elective treatment after careful clinical and radiological investigation. In these conditions, communication between orthopaedic surgeon and radiologist allow to create a detailed radiology report, tailored to the patient's and surgeon's needs and optimal to plan proper management. Imaging technique as X-Ray, CT, US, MRI, CTA and MRA all belong to the radiologist's portfolio in elbow diagnostics. Detailed knowledge of elbow pathology and its classification and of the possibilities and limits of each imaging technique is of crucial importance to reach the correct diagnosis efficiently. The aim of this review is to present the most frequent elbow pathologies and suggest a suitable diagnostic approach for each of them.

Early combined arthroscopic treatment for simultaneous ruptures of the patellar tendon and the anterior cruciate ligament leads to good radiological results and patient satisfaction.

PURPOSE: Simultaneous rupture of the patellar tendon (PT) and the anterior cruciate ligament (ACL) is a relatively rare injury. This study offers a comprehensive review of the published reports and presents two cases of simultaneous PT and ACL rupture. METHODS: A systematic review of English literature was performed, and data from two patients who were referred to our institution with simultaneous PT and ACL rupture were collected. Both patients underwent primary arthroscopic ACL reconstruction combined with PT reconstruction and, 1 year after surgery, magnetic resonance imaging (MRI), clinical examination, strength measurement and functional assessment. RESULTS: Fourteen studies (24 patients) were included in the review. A two-stage approach was used in eight cases (33.3%), and in nine the use of arthroscopy was documented (37.5%). Post-operative scores were documented for nine patients (average IKDC 91.2; Lysholm 94.6), and radiological results were provided for seven. In the two newly reported cases, satisfactory functional results were obtained and MRI at 1-year follow-up revealed regular PT and ACL signal. CONCLUSIONS: No consensus has been established for neither a diagnostic nor a therapeutic algorithm for simultaneous PT and ACL ruptures. Early combined arthroscopic treatment leads to good radiological results, accelerated recovery and patient satisfaction; further studies are required to confirm the role of arthroscopy and assess the superiority of a specific technique. LEVEL OF EVIDENCE: Review of level IV and V studies and case series, Level IV.

Transient Esotropia in the Child: Case Report and Review of the Literature.

The aim of this report is to investigate the possible causes of acute acquired onset of transient esotropia (AATE) in children and to help to differentiate ophthalmoplegic migraine (OM) from accommodative spasm (AS). A case of an 8-year-old Caucasian female affected by AATE and diplopia is described. The day before AATE onset, the patient complained of slight headache without nausea and vomiting, with spontaneous resolution. AATE diagnosis is challenging. The most likely ophthalmological causes of AATE are AS and OM. In these cases it is important to evaluate the presence of both a familial history of recurrent headaches and an AATE associated with migraine, ptosis, nausea, and vomiting. A full ophthalmological evaluation and a thorough refractive examination in cycloplegia are mandatory to exclude ophthalmological causes.

Microwave Ablation of the Lung in a Porcine Model: Vessel Diameter Predicts Pulmonary Artery Occlusion.

PURPOSE: To determine the size of pulmonary artery (PA) at risk for occlusion during percutaneous microwave ablation and to assess the effect of vessel diameter, number, and patency, on ablation zone volume. MATERIALS AND METHODS: Computed tomography (CT) fluoroscopy-guided percutaneous microwave ablations were performed in 8 pigs under general anesthesia. All ablations were performed at 65 W for 5 min with a single 17-gauge antenna positioned in the central third of the lungs. A CT pulmonary angiogram was performed immediately after the ablations. The maximum diameter, number and patency of PA branches within each ablation zone were recorded. Ablation volumes were measured at gross dissection and with CT. Student's t test was used to compare ablation zone volumes among groups. RESULTS: Twenty-one pulmonary ablations were performed. Six of the ablation zones (29%) contained at least 1 occluded PA branch. The mean diameter of the occluded PA branches in the ablation zones (2.4 mm; range, 2.0-2.8 mm) was significantly smaller than non-occluded PA branches (3.7 mm; range: 2.1-6.9 mm; p = 0.009). No PA branches ≥3 mm in size were occluded. There was no significant difference in volume of gross ablation zones that contained occluded versus non-occluded PAs (p = 0.42), one versus multiple PAs (p = 0.71), or PAs <3 mm versus ≥3 mm in diameter (p = 0.44). CONCLUSIONS: PAs ≥3 mm in size have a low risk for iatrogenic occlusion during percutaneous microwave ablation. The presence of multiple adjacent PA branches, an occluded PA branch, and a vessel diameter ≥3 mm within the ablation zone had no observed effect on ablation zone volume.

Microwave ablation in primary and secondary liver tumours: technical and clinical approaches.

Thermal ablation is increasingly being utilised in the treatment of primary and metastatic liver tumours, both as curative therapy and as a bridge to transplantation. Recent advances in high-powered microwave ablation systems have allowed physicians to realise the theoretical heating advantages of microwave energy compared to other ablation modalities. As a result there is a growing body of literature detailing the effects of microwave energy on tissue heating, as well as its effect on clinical outcomes. This article will discuss the relevant physics, review current clinical outcomes and then describe the current techniques used to optimise patient care when using microwave ablation systems.

MR visible localization device for radiographic-pathologic correlation of surgical specimens.

PURPOSE: The detection of small parenchymal hepatic lesions identified by preoperative imaging remains a challenge for traditional pathologic methods in large specimens. We developed a magnetic resonance imaging (MRI) compatible localization device for imaging of surgical specimens aimed to improve identification and localization of hepatic lesions ex vivo. MATERIALS AND METHODS: The device consists of two stationary and one removable MR-visible grids lined with silicone gel, creating an orthogonal 3D matrix for lesion localization. To test the device, five specimens of swine liver with a random number of lesions created by microwave ablation were imaged on a 3T MR scanner. Two readers independently evaluated lesion coordinates and size, which were then correlated with sectioning guided by MR imaging. RESULTS: All lesions (n=38) were detected at/very close to the expected localization. Inter-reader agreement of lesion localization was almost perfect (0.92). The lesion size estimated by MRI matched macroscopic lesion size in cut specimen (±2mm) in 34 and 35, respectively, out of 38 lesions. CONCLUSION: Use of this MR compatible device for ex vivo imaging proved feasible for detection and three-dimensional localization of liver lesions, and has potential to play an important role in the ex vivo examination of surgical specimens in which pathologic correlation is clinically important.

Pulmonary Microwave Ablation Near the Heart: Antenna Positioning Can Mitigate Cardiac Complications in a Porcine Model.

Purpose To determine how close to the heart pulmonary microwave ablation can be performed without causing cardiac tissue injury or significant arrhythmia. Materials and Methods The study was performed with approval from the institutional animal care and use committee. Computed tomographic fluoroscopically guided microwave ablation of the lung was performed in 12 swine. Antennas were randomized to either parallel (180° ± 20°) or perpendicular (90° ± 20°) orientation relative to the heart surface and to distances of 0-10 mm from the heart. Ablations were performed at 65 W for 5 minutes or until a significant arrhythmia (asystole, heart block, bradycardia, supraventricular or ventricular tachycardia) developed. Heart tissue was evaluated with vital staining and histologic examination. Data were analyzed with mixed effects logistic regression, receiver operating characteristic curves, and the Fisher exact test. Results Thirty-four pulmonary microwave ablations were performed with the antenna a median distance of 4 mm from the heart in both perpendicular (n = 17) and parallel (n = 17) orientation. Significant arrhythmias developed during six (18%) ablations. Cardiac tissue injury occurred with 17 ablations (50%). Risk of arrhythmia and tissue injury decreased with increasing antenna distance from the heart with both antenna orientations. No cardiac complication occurred with a distance of greater than or equal to 4.4 mm from the heart. The ablation zone extended to the pleural surface adjacent to the heart in 71% of parallel and 17% of perpendicular ablations performed 5-10 mm from the heart. Conclusion Microwave lung ablations performed more than or equal to 5 mm from the heart were associated with a low risk of cardiac complications. © RSNA, 2016.

Grisel's syndrome, a rare cause of anomalous head posture in children: a case report.

BACKGROUND: Anomalous head posture (AHP) or torticollis is a relatively common condition in children. Torticollis is not a diagnosis, but it is a sign of underlying disease. Grisel's syndrome (GS) is a rare condition of uncertain etiology characterized by a nontraumatic atlanto-axial subluxation (AAS), secondary to an infection in the head and neck region. It has not been considered, in ophthalmological papers, as a possible cause of AHP. CASE PRESENTATION: A case of AAS secondary to an otitis media is studied. The children showed neck pain, head tilt, and reduction in neck mobility. The patient had complete remission with antibiotic and anti-inflammatory therapy and muscle relaxants. Signs of GS should always be taken into account during ophthalmological examination (recent history of upper airway infections and/or head and neck surgeries associated to a new onset of sudden, painful AHP with normal ocular exam). In such cases it is necessary to require quick execution of radiological examinations (computer tomography and/or nuclear magnetic resonance), which are essential to confirm the diagnosis. CONCLUSION: GS is a multidisciplinary disease. We underline the importance of an accurate orthoptic and ophthalmological examination. Indeed, early detection and diagnosis are fundamental to achieve proper management, avoid neurological complications and lead to a good prognosis.