Intralesional therapies for vascular malformations of the head and neck.

Vascular malformations of the head and neck represent a spectrum of complex vascular anomalies, requiring a multidisciplinary approach toward diagnosis and treatment. Several intralesional therapeutic agents have been devised and pioneered over the years, some of which are now primary and standard of care for the management of these lesions. In this article, the authors discuss the currently available intralesional therapeutic agents for the management of vascular malformations in the head and neck region.

Utilization and Outcomes of Cholecystostomy and Cholecystectomy in Patients Admitted With Acute Cholecystitis: A Nationwide Analysis.

OBJECTIVE. The purpose of this study was to report national utilization trends and outcomes after percutaneous cholecystostomy, cholecystectomy, or no intervention among patients admitted to hospitals with acute cholecystitis. MATERIALS AND METHODS. The Nationwide Inpatient Sample was queried from 2005 to 2014. Admissions were identified and stratified into treatment groups of percutaneous cholecystostomy, cholecystectomy, and no intervention on the basis of International Classification of Diseases, 9th revision, codes. Outcomes, including length of stay, inpatient mortality, and complications including hemorrhage and bile peritonitis, were identified. Multivariate analysis was performed to identify mortality risk by treatment type after adjustment for baseline comorbidities and risk of mortality. RESULTS. Among 2,550,013 patients (58.6% women, 41.4% men; mean age, 55.9 years) admitted for acute cholecystitis over the study duration, 73,841 (2.9%) patients underwent percutaneous cholecystostomy, 2,005,728 (78.7%) underwent cholecystectomy, and 459,585 (18.0%) did not undergo either procedure. Use of percutaneous cholecystostomy increased from 2985 procedures in 2005 to 12,650 in 2014. The percutaneous cholecystostomy cohort had a higher mean age (70.6 years) than the other two groups (cholecystectomy, 53.8 years; no intervention, 62.5 years), a higher mean comorbidity index (cholecystostomy, 3.74; cholecystectomy, 1.77; no intervention, 2.65), and a higher mean risk of mortality index (cholecystostomy, 2.88; cholecystectomy, 1.45; no intervention, 2.07) (p < .05). Unadjusted inpatient all-cause mortality was 10.1% in the percutaneous cholecystostomy, 0.8% in the cholecystectomy, and 5.2% in the no intervention cohorts. After adjustment for baseline mortality risk, percutaneous cholecystostomy (odds ratio, 0.78; 95% CI, 0.76-0.81) and cholecystectomy (odds ratio, 0.42; 95% CI, 0.41-0.43) were associated with reduced mortality compared with no intervention. CONCLUSION. Use of percutaneous cholecystostomy is increasing among patients admitted with acute cholecystitis. After adjustment for baseline comorbidities, percutaneous cholecystostomy is associated with improved odds of survival compared with no intervention.

Pediatric interventional radiology workforce in North America: a descriptive analysis of demographics, educational backgrounds and scholarly activities.

BACKGROUND: Pediatric interventional radiology has grown as an advanced subspecialty with increased demand, number and complexity of cases, and number of pediatric institutions offering a pediatric interventional radiology service. Despite the overall increase in the number of pediatric interventionalists over the past two decades, there is a heterogeneity in their academic backgrounds and a lack of uniform training pathways. OBJECTIVE: To analyze the demographics, academic backgrounds and scholarly activities of pediatric interventionalists across the United States (U.S.) and Canada. MATERIALS AND METHODS: A list of all members of the Society for Pediatric Interventional Radiology was obtained and pediatric interventionalists at academic and private practice institutions in the U.S. and Canada were included. Publicly available online sources were used to gather demographic and educational information about each pediatric interventionalist, which included the online curriculum vitae, the HealthGrades.com and Doximity.com websites, and Elsevier's Scopus database. Demographic and educational data including age, gender, educational background, additional degrees, academic rank, previous leadership positions, and metrics of scholarly activities were recorded. Fellowships in diagnostic pediatric radiology, adult interventional radiology and/or pediatric interventional radiology were recorded. Mann-Whitney U tests and Kruskal-Wallis tests were used to compare differences between groups. RESULTS: One hundred and twenty-five pediatric interventionalists were included, of whom 24 (19.2%) were female. The mean age was 48.6 years (standard deviation [SD]: 10.6, median: 45 years, range: 36-82 years). There was no statistical difference between median age for male versus female pediatric interventionalists (44.5 years vs. 45 years, P=0.89). A majority of pediatric interventionalists were American medical school graduates (96, 76.8%), while 29 (23.2%) were international medical graduates. Eighty-three percent (104) of the pediatric interventionalists completed diagnostic radiology residency training in the U.S., most commonly at the University of Cincinnati in Ohio (6.4%) and Washington University in St. Louis, MO (5.6%). Among fellowship training, pediatric interventionalists completed a pediatric radiology fellowship (61.6%), adult interventional radiology fellowship (40%) and/or a dedicated pediatric interventional radiology fellowship (57.6%). The mean±SD (median) publications, citations and Hirsch index (h-index) for pediatric interventionalists were 32±45 (12), 68±1,317 (120) and 9±10 (5), respectively. There was a statistically higher number of publications, citations and h-index with increasing academic rank at the assistant, associate and professor levels (P<0.001 for all groups). International medical graduate pediatric interventionalists had a higher, but not statistically significant, median publication count (26 vs. 11, P=0.0.25), citation count (236 vs. 93, P=0.36) and h-index (9.0 vs. 5, P=0.24) compared to pediatric interventional radiologists from American medical schools. CONCLUSION: Pediatric interventionalists in North America are predominantly male, with about a quarter having graduated from international medical schools. Pediatric radiology fellowship, followed by pediatric interventional radiology fellowship, was the most frequently pursued training pathway.

Current perspectives in conventional and advanced imaging of the distal radioulnar joint dysfunction: review for the musculoskeletal radiologist.

Distal radioulnar joint (DRUJ) dysfunction is a common cause of ulnar sided wrist pain. Physical examination yields only subtle clues towards the underlying etiology. Thus, imaging is commonly obtained towards an improved characterization of DRUJ pathology, especially multimodality imaging, which is frequently resorted to arrive at an accurate diagnosis. With increasing use of advanced MRI and CT techniques, DRUJ imaging has become an important part of a musculoskeletal radiologist's practice. This article discusses the normal anatomy and biomechanics of the DRUJ, illustrates common clinical abnormalities, and provides a comprehensive overview of the imaging evaluation with an insight into the role of advanced cross-sectional modalities in this domain.

In-Hospital Mortality Benefit of Inferior Vena Cava Filters in Patients With Pulmonary Embolism and Congestive Heart Failure.

OBJECTIVE: Pulmonary embolism (PE) is associated with a higher mortality rate in patients with congestive heart failure (CHF) than in those without heart failure. The purpose of this study was to evaluate if inferior vena cava (IVC) filter placement provides any mortality benefit in patients admitted with CHF and PE. MATERIALS AND METHODS: The 2005-2014 Nationwide Inpatient Sample (NIS) was used for this study. Adults (≥ 18 years old) with PE were identified using International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) diagnosis codes. Patients with CHF were identified using the Elixhauser comorbidity variable (CM_CHF) in the NIS database. IVC filter placement was identified using the ICD-9-CM procedure code 38.7 (interruption of the vena cava). A multivariate logistic regression model was used to determine the association of IVC filter placement with in-hospital mortality. The model was adjusted for demographics, hospital characteristics, comorbidities, and PE severity indexes (pressor dependence, mechanical ventilation, nonseptic shock, and use of thrombolytic therapy). RESULTS: During the study years, 425,877 patients with a comorbidity of CHF were hospitalized with PE (44% male; mean age, 71.5 years old). Of them, 67,237 patients (15.8%) received an IVC filter during the admission, and 50,338 (11.8%) died during the hospital stay. The all-cause in-hospital mortality rate among patients who received an IVC filter was 9.7% (6541 of 67,237 patients) compared with 12.2% (43,796 of 358,638 patients) among those without an IVC filter (p < 0.001), with an absolute risk reduction of 2.5%. The multivariate adjusted hazard ratio of in-hospital mortality associated with IVC filter placement was 0.535 (95% CI, 0.518-0.551; p < 0.001). CONCLUSION: A lower all-cause mortality rate was observed in patients with CHF and PE who received an IVC filter while hospitalized. In the absence of data from randomized controlled trials, this study suggests that IVC filters could help prevent in-hospital death among patients admitted with PE and CHF.

MR Neurographic Evaluation of Facial and Neck Pain: Normal and Abnormal Craniospinal Nerves below the Skull Base.

Cranial nerve disease outside the skull base is a common cause of facial and/or neck pain, which causes significant disability for patients and frustration for clinicians. Neuropathy in this region can be traumatic, idiopathic, or iatrogenic secondary to dental and surgical procedures. MR neurography is a modification of conventional MRI techniques dedicated to evaluation of peripheral nerves and is being increasingly used for imaging of peripheral neuropathies at various sites in the body. MR neurography facilitates assessment of different causes of craniofacial pain and cranial nerves and allows elegant depiction of a multitude of regional neuropathies. This article discusses the anatomy, pathologic conditions, and imaging findings of the commonly implicated but difficult to image infratentorial nerves, such as the peripheral trigeminal nerve and its branches, facial nerve, glossopharyngeal nerve, vagus nerve, hypoglossal nerve, and greater and lesser occipital nerves. ©RSNA, 2018.

New concepts of radiologic preoperative evaluation of anterior shoulder instability: on-track and off-track lesions.

The shoulder is the most frequently dislocated joint in the body due to a larger range of motion and a small area of articulation between the humeral and glenoid surfaces. Traumatic shoulder dislocations, especially those associated with injury to the labroligamentous or bony stabilizers of the joint, lead to further reduction of articular surface contact with resultant glenohumeral instability and recurrent shoulder dislocations. Imaging plays an increasingly important role in the preoperative evaluation of patients with traumatic shoulder instability by evaluating glenohumeral bone loss (uni- or bipolar), assessing soft tissue injuries and identifying patients at risk of postoperative recurrence. Quantification of bone loss is key to differentiate engaging vs. non-engaging Hill-Sachs lesions, while newer concepts of "on-track" vs. "off-track" lesions are being discussed that can determine the required surgical approaches. In this article, we review the preoperative imaging approaches, traditional treatments, outline the bone loss measurement strategies and review these new tracking concepts with relevant case examples.

IVC filter placements in children: nationwide comparison of practice patterns at adult and children's hospitals using the Kids' Inpatient Database.

BACKGROUND: Inferior vena cava (IVC) filter placement in children has been described in literature, but there is variability with regard to their indications. No nationally representative study has been done to compare practice patterns of filter placements at adult and children's hospitals. OBJECTIVE: To perform a nationally representative comparison of IVC filter placement practices in children at adult and children's hospitals. MATERIALS AND METHODS: The 2012 Kids' Inpatient Database was searched for IVC filter placements in children <18 years of age. Using the International Classification of Diseases, 9th Revision (ICD-9) code for filter insertion (38.7), IVC filter placements were identified. A small number of children with congenital cardiovascular anomalies codes were excluded to improve specificity of the code used to identify filter placement. Filter placements were further classified by patient demographics, hospital type (children's and adult), United States geographic region, urban/rural location, and teaching status. Statistical significance of differences between children's or adult hospitals was determined using the Wilcoxon rank sum test. RESULTS: A total of 618 IVC filter placements were identified in children <18 years (367 males, 251 females, age range: 5-18 years) during 2012. The majority of placements occurred in adult hospitals (573/618, 92.7%). Significantly more filters were placed in the setting of venous thromboembolism in children's hospitals (40/44, 90%) compared to adult hospitals (246/573, 43%) (P<0.001). Prophylactic filters comprised 327/573 (57%) at adult hospitals, with trauma being the most common indication (301/327, 92%). The mean length of stay for patients receiving filters was 24.5 days in children's hospitals and 18.4 days in adult hospitals. CONCLUSION: The majority of IVC filters in children are placed in adult hospital settings. Children's hospitals are more likely to place therapeutic filters for venous thromboembolism, compared to adult hospitals where the prophylactic setting of trauma predominates.

Role of Diffusion Weighted Imaging in Musculoskeletal Infections: Current Perspectives.

Accurate diagnosis and prompt therapy of musculoskeletal infections are important prognostic factors. In most cases, clinical history, examination and laboratory findings help one make the diagnosis, and routine magnetic resonance imaging (MRI) is useful to identify the extent of the disease process. However, in many situations, a routine MRI may not be specific enough especially if the patient cannot receive contrast intravenously, thereby delaying the appropriate treatment. Diffusion-weighted imaging (DWI) can help in many such situations by providing additional information, accurate characterization and defining the extent of the disease, so that prompt treatment can be initiated. In this article, we illustrate the imaging findings of the spectrum of musculoskeletal infections, emphasizing the role of DWI in this domain. KEY POINTS: • Abscess in background cellulitis is detected on DWI. • Infectious tenosynovitis shows diffusion restriction as compared to mechanical tenosynovitis. • Pyomyositis with abscess can be differentiated from diabetic myonecrosis on DWI. • Intraosseous abscess is bright on DWI versus devitalized tissue, sequestrum and air. • DWI can be used to differentiate spine infection from simple Modic changes.

Pudendal nerve and branch neuropathy: magnetic resonance neurography evaluation.

Pudendal neuralgia is being increasingly recognized as a cause of chronic pelvic pain, which may be related to nerve injury or entrapment. Due to its complex anatomy and branching patterns, the pudendal nerve abnormalities are challenging to illustrate. High resolution 3 T magnetic resonance neurography is a promising technique for the evaluation of peripheral neuropathies. In this article, the authors discuss the normal pudendal nerve anatomy and its variations, technical considerations of pudendal nerve imaging, and highlight the normal and abnormal appearances of the pudendal nerve and its branches with illustrative case examples.

Skin marker placement by technologist prior to knee MRI helps identify clinically relevant pathologies.

BACKGROUND: Majority of musculoskeletal cross-sectional imaging requests have a non-revealing and non-specific clinical history of pain. However, the location of pain is very relevant towards arriving at a specific orthopedic diagnosis. The purpose of this research was to study the impact of skin marker placement and training of technologists prior to knee MRI in detection of clinically important findings. METHODS: Total 200 consecutive left knee MRIs were evaluated before and after technologist training with regards to marker placement at the site of clinical symptoms or palpable finding. Marker location in relation to the knee was recorded and important findings were classified as correlated important finding, non-correlated important finding, other compartment important finding in non-correlated cases, and diffuse abnormality, i.e. tri-compartmental cartilage defects in both correlated and non-correlated cases. Differences among scans before and after technologist training were analyzed. RESULTS: The marker placement was observed in higher proportion of patients in post-training scans (78% vs 60%, p = 0.00). The most common location of the marker was in anterior or anterolateral knee (32% and 34% cases, respectively). The marker-important finding correlation was also higher post training, but not statistically significant (53% versus 38%, p = 0.57). Important findings correlated with the marker in more than 50% of the scans in the post-training set. CONCLUSION: Marker placement can aid in detection of clinically important imaging finding and technologist training aids in increased rates of marker placement and improved correlation.

MRI in flexor tendon rupture after collagenase injection.

Flexor tendon rupture is an unusual complication following collagenase injection to relieve contractures. These patients require a close follow-up and in the event of tendon rupture, a decision has to be made whether to repair the tendon or manage the complication conservatively. The authors report the utility of MRI in the prognostication and management of a patient with Dupuytren's contracture, who underwent collagenase injection and subsequently developed flexor digitorum profundus tendon rupture.

Kinematic Magnetic Resonance Imaging of Peroneal Tendon Subluxation with Intraoperative Correlation.

Magnetic resonance imaging (MRI) is a noninvasive modality of choice for the detection of static peroneal tendon pathologic features. The depiction of peroneal tendon subluxation using real-time kinematic MRI has not been previously reported. We describe the MRI and intraoperative correlation of peroneal tendon and retinacular pathologic findings, and the novel use of kinematic MRI in the illustration of peroneal tendon subluxation.

Ipilimumab Induced Hypophysitis: MRI Findings in a Series of 3 Cases.

ypophysitis is a reported compli- cation of ipilimumab, a monoclo- nal antibody which augments T- cell response against tumors. The imaging changes in the pituitary may precede or coincide with the hypopituitarism, but are frequently over- looked due to the subtle alteration in size and en- hancement characteristics. We present a series of 3 patients who developed hypophysitis and pituitary dysfunction subsequent to ipilimumab therapy and describe the MR imaging features and make follow up recommendations.

Whole-body MR neurography: Prospective feasibility study in polyneuropathy and Charcot-Marie-Tooth disease.

PURPOSE: To evaluate the feasibility of whole-body magnetic resonance neurography (WBMRN) in polyneuropathy for technical feasibility, distribution of nerve abnormalities, and differentiation. MATERIALS AND METHODS: Twenty WBMRN examinations were performed on a 3T scanner over 2 years. Patient demographics including history of hereditary and acquired neuropathy were recorded. The images were evaluated by two independent readers with nerve imaging experience for quality. The nerve signal and size alterations were measured in the brachial plexus, lumbosacral plexus, and femoral and sciatic nerves; diffusion tensor imaging parameters (fractional anisotropy [FA] and apparent diffusion coefficient [ADC]) were determined in plexuses, and tractography was performed. Nonparametric Wilcoxon rank sum test, receiver operating characteristic (ROC) analysis, and intraclass correlation coefficients (ICCs) were obtained. RESULTS: Excellent image quality was obtained for the majority of lumbosacral (LS) plexus (18/20) and 50% of brachial plexus (10/20) regions. Qualitatively among cases, the nerve hyperintensity and/or thickening involved the brachial plexus (11/11), LS plexus (7/11), and both plexuses (7/11), with most nerve thickenings observed in Charcot-Marie-Tooth disease type 1. The nerve signal intensity alterations were significantly different for both brachial (P < 0.05) and LS (P < 0.05) plexuses in cases versus controls. The femoral and sciatic nerve size alterations were different (P < 0.05), while signal intensity differences were not significant (P = 0.1-0.97). Transverse dimensions of C8 (4 mm), L5 (6.2 mm) and S1 (5.1 mm) nerve roots, and sciatic nerves (10.2 mm) were the most accurate diagnostic performance measures in distinguishing cases from controls. CONCLUSION: WBMRN is feasible for use in the clinical practice for the identification and potential characterization of polyneuropathy. J. Magn. Reson. Imaging 2016;44:1513-1521.

T2 black lesions on routine knee MRI: differential considerations.

The majority of abnormal findings or lesions on T2-weighted fast spin-echo (FSE) magnetic resonance imaging (MRI) are hyperintense due to increased perfusion or fluid content, such as infections, tumours or synovitis. Hypointense lesions on T2-weighted images (both fat-suppressed and non-fat-suppressed) are less common and can sometimes be overlooked. Such lesions have limited differential diagnostic possibilities, and include vacuum phenomenon, loose body, tenosynovial giant cell tumour, rheumatoid arthritis, haemochromatosis, gout, amyloid, chondrocalcinosis, hydroxyapetite deposition disease, lipoma arborescens, arthrofibrosis and iatrogenic lesions. These lesions often show characteristic appearances and predilections in the knee. In this article, the authors describe the MRI features of hypointense T2 lesions on routine knee MRI and outline a systematic diagnostic approach towards their evaluation. Key Points • Hypointense lesions on T2 images (T2 Dark Lesions) encompass limited diagnostic possibilities. • T2 Dark lesions often show characteristic appearances and predilections in the knee. • A systematic diagnostic approach will help radiologists make the correct diagnosis.

CT-guided Perineural Injections for Chronic Pelvic Pain.

Chronic pelvic pain is a disabling condition that affects a large number of men and women. It may occur after a known inciting event, or it could be idiopathic. A common cause of pelvic pain syndrome is neuropathy of the pelvic nerves, including the femoral and genitofemoral nerves, ilioinguinal and iliohypogastric nerves, pudendal nerve, obturator nerve, lateral and posterior femoral cutaneous nerves, inferior cluneal nerves, inferior rectal nerve, sciatic nerve, superior gluteal nerve, and the spinal nerve roots. Pelvic neuropathy may result from entrapment, trauma, inflammation, or compression or may be iatrogenic, secondary to surgical procedures. Imaging-guided nerve blocks can be used for diagnostic and therapeutic management of pelvic neuropathies. Ultrasonography (US)-guided injections are useful for superficial locations; however, there can be limitations with US, such as its operator dependence, the required skill, and the difficulty in depicting various superficial and deep pelvic nerves. Magnetic resonance (MR) imaging-guided injections are radiation free and lead to easy depiction of the nerve because of the superior soft-tissue contrast; although the expense, the required skill, and the limited availability of MR imaging are major hindrances to its widespread use for this purpose. Computed tomography (CT)-guided injections are becoming popular because of the wide availability of CT scanners, the lower cost, and the shorter amount of time required to perform these injections. This article outlines the technique of perineural injection of major pelvic nerves, illustrates the different target sites with representative case examples, and discusses the pitfalls. (©)RSNA, 2016.

Patellar instability: CT and MRI measurements and their correlation with internal derangement findings.

PURPOSE: To test the inter-observer and inter-method reliability among the measures suggesting patellofemoral joint disorder on both CT and MRI in the same subject and find possible association with internal derangements of the patellofemoral joint on MRI. METHODS: Institutional review board approval was obtained with waiver of the informed consent in this HIPPA-compliant study. CT and MRI were evaluated in 32 knees in 32 respective subjects (10 men/22 women, mean age 38 ± 19 years). Three trained observers assessed tibial tuberosity-trochlear groove (TT-TG) distance, trochlear angle and trochlear depth on both CT and MRI. Intra-class correlation coefficient (ICC) was used to evaluate inter-observer and inter-method reliability. Two radiologists' consensus reading was used to evaluate their association with soft tissue abnormalities of the patellofemoral joint. Chi-square test was used to assess the statistical significance of the qualitative variables. RESULTS: There was an excellent inter-observer reliability (ICC for CT >0.89 and for MRI >0.90) and inter-method reliability (ICC >0.86) for all the quantitative measurements. There was a significant association between increased TT-TG distance value on MR imaging and lateral facet patellar cartilage abnormality and joint effusion (p < 0.05). CONCLUSION: Quantitative trochlear parameters can be reliably calculated on MRI, and an abnormal TT-TG distance is the most useful measurement among various static MR imaging parameters to correlate with patellar chondrosis and joint effusion. TT-TG distance should be reported in patellofemoral pain syndrome patients. LEVEL OF EVIDENCE: IV.

SHINKEI--a novel 3D isotropic MR neurography technique: technical advantages over 3DIRTSE-based imaging.

OBJECTIVES: Technical assessment of SHINKEI pulse sequence and conventional 3DIRTSE for LS plexus MR neurography. METHODS: Twenty-one MR neurography examinations of the LS plexus were performed at 3 T, using 1.5-mm isotropic 3DIRTSE and SHINKEI sequences. Images were evaluated for motion and pulsation artefacts, nerve signal-to-noise ratio, contrast-to-noise ratio, nerve-to-fat ratio, muscle-to-fat ratio, fat suppression homogeneity and depiction of LS plexus branches. Paired Student t test was used to assess differences in nerve conspicuity (p < 0.05 was considered statistically significant). ICC correlation was obtained for intraobserver performance. RESULTS: Four examinations were excluded due to prior spine surgery. Bowel motion artefacts, pulsation artefacts, heterogeneous fat saturation and patient motion were seen in 16/17, 0/17, 17/17, 2/17 on 3DIRTSE and 0/17, 0/17, 0/17, 1/17 on SHINKEI. SHINKEI performed better (p < 0.01) for nerve signal-to-noise, contrast-to-noise, nerve-to-fat and muscle-to-fat ratios. 3DIRTSE and SHINKEI showed all LS plexus nerve roots, sciatic and femoral nerves. Smaller branches including obturator, lateral femoral cutaneous and iliohypogastric nerves were seen in 10/17, 5/17, 1/17 on 3DIRTSE and 17/17, 16/17, 7/17 on SHINKEI. Intraobserver reliability was excellent. CONCLUSION: SHINKEI MRN demonstrates homogeneous and superior fat suppression with increased nerve signal- and contrast-to-noise ratios resulting in better conspicuity of smaller LS plexus branches. KEY POINTS: • SHINKEI provides homogeneous and superior fat suppression, shown by higher nerve and muscle-to-fat ratios. • SHINKEI shows better nerve signal-to-noise and contrast-to-noise ratios than 3DIRTSE. • SHINKEI enables nerve-selective images with increased conspicuity of smaller LS plexus branches. • SHINKEI should be considered in routine MR neurography of the LS plexus.