Faculty Bibliography

A 57-year-old male presented with recurrent falls, bilateral lower-limb paresthesia, and severe neck pain. Imaging revealed a mass compressing his spinal cord. He was admitted for further workup for spinal cord compression. Within 24 hours of admission, he developed upper-extremity weakness while maintaining lower-extremity function. He underwent urgent decompression of his spinal cord. During exposure, a white, creamy odorless substance was noted. This same substance was found under pressure within the spinal canal. The mass was grossly removed, and the patient's weakness improved postoperatively. Based on the clinical picture, intraoperative presentation, and final histological examination, idiopathic tumoral calcinosis-like lesion was considered as the most appropriate diagnosis.

OBJECTIVES/OBJECTIVE:To determine the efficacy and safety of percutaneous calcitonin and steroid injection in the treatment of aneurysmal bone cysts (ABCs). MATERIALS AND METHODS/METHODS:Our study was IRB-approved and HIPAA-compliant. We reviewed pre- and post-procedural imaging studies and medical records of all CT-guided percutaneous injections of ABCs with calcitonin and steroid performed at our institution between 2003 and 2015. RESULTS:Treatment success based on imaging was categorized as substantial (51-100 %), partial (1-50 %), or none (0 %) by comparing radiographs of the lesion before and after treatment. Our study group comprised 9 patients (7 female, 2 male; mean age 19 ± 5 (range 12-25) years). ABCs were located in the pubis (n = 3), femur (n = 2), and humerus/scapula/ilium/sacrum (n = 1 for each). One patient did not have any clinical or imaging follow-up. For the other 8 patients, clinical and imaging follow-up ranged from 1 to 93 months (mean 16 ± 29 months). One patient had two injections, and 1 patient had three injections. Six out of eight patients (75 %) had complete symptomatic relief and 2 patients (25 %) had partial symptomatic relief after initial injection. Imaging follow-up revealed substantial imaging response in 4 out of 8 patients (50 %). There was a partial imaging response in 2 patients (25 %) and no imaging response in 2 out of 8 patients (25 %), and all 4 of these patients had local recurrence. There were no complications. CONCLUSION/CONCLUSIONS:Percutaneous CT-guided injection of ABCs with calcitonin and steroid is a safe and effective treatment. Lack of imaging response may necessitate more aggressive treatment to minimize local recurrence.

Body composition differs between men and women. Men have more lean mass, and women have more fat mass than men. Men are more likely to accumulate adipose tissue around the trunk and abdomen, whereas women usually accumulate adipose tissue around the hips and thighs. Less is known about sex differences in ectopic fat depots. Advances in imaging allow the noninvasive assessment of abdominal and femorogluteal fat compartments, intramyocellular lipids, intrahepatic lipids, pericardial adipose tissue, and neck adipose tissue including brown adipose tissue and tongue adipose tissue. In this review, sex differences of regional adipose tissue, muscle mass, ectopic lipids, and brown adipose tissue and their effects on cardiometabolic risk will be discussed. In addition, novel imaging techniques to quantify these body composition compartments noninvasively will be described.

OBJECTIVES/OBJECTIVE:To assess CT-attenuation of abdominal adipose tissue and psoas muscle as predictors of mortality in patients with sarcomas of the extremities. METHODS:Our study was IRB approved and HIPAA compliant. The study group comprised 135 patients with history of extremity sarcoma (mean age: 53 ± 17 years) who underwent whole body PET/CT. Abdominal subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), and psoas muscle attenuation (HU) was assessed on non-contrast, attenuation-correction CT. Clinical information including survival, tumour stage, sarcoma type, therapy and pre-existing comorbidities were recorded. Cox proportional hazard models were used to determine longitudinal associations between adipose tissue and muscle attenuation and mortality. RESULTS:There were 47 deaths over a mean follow-up period of 20 ± 17 months. Higher SAT and lower psoas attenuation were associated with increased mortality (p = 0.03 and p = 0.005, respectively), which remained significant after adjustment for age, BMI, sex, tumor stage, therapy, and comorbidities (p = 0.002 and p = 0.02, respectively). VAT attenuation was not associated with mortality. CONCLUSION/CONCLUSIONS:Attenuation of SAT and psoas muscle, assessed on non-contrast CT, are predictors of mortality in patients with extremity sarcomas, independent of other established prognostic factors, suggesting that adipose tissue and muscle attenuation could serve as novel biomarkers for mortality in patients with sarcomas. KEY POINTS/CONCLUSIONS:• CT-attenuation of adipose tissue and muscle predict mortality in sarcoma patients • CT-attenuation predicts mortality independent of established prognostic factors • Patients with sarcomas often undergo CT for staging or surveillance • Adipose tissue and muscle attenuation could serve as biomarkers for mortality.

OBJECTIVE:To examine associations between tongue adiposity with upper airway measures, whole-body adiposity and gender. We hypothesized that increased tongue adiposity is higher in males and positively associated with abnormal upper airway measures and whole-body adiposity. METHODS:We studied subjects who underwent whole-body positron emission tomography/computed tomography to obtain tongue attenuation (TA) values and cross-sectional area, pharyngeal length (PL) and mandibular plane to hyoid distance (MPH), as well as abdominal circumference, abdominal subcutaneous and visceral (VAT) adipose tissue areas, neck circumference (NC) and neck adipose tissue area. Metabolic syndrome was determined from available clinical and laboratory data. RESULTS:). Males had lower TA values (P=0.0002) and higher upper airway measures (P<0.0001) independent of age and BMI (P<0.001). In all subjects, TA was negatively associated with upper airway measures (P<0.001). TA was negatively associated with body composition parameters (all P<0.0001), most notably with VAT (r=-0.53) and NC (r=-0.47). TA values were lower in subjects with metabolic syndrome (P<0.0001). CONCLUSION/CONCLUSIONS:Increased tongue adiposity is influenced by gender and is associated with abnormal upper airway patency and body composition parameters.

OBJECTIVE:The purpose of this study was (1) to evaluate the association of trunk muscle density assessed by computed tomography (CT) with age, gender, and BMI and (2) to evaluate the association between trunk muscle CT density and degenerative disc and facet joint disease of the lumbar spine. MATERIAL AND METHODS/METHODS:The study was IRB approved and HIPAA compliant. The study group comprised 100 subjects (mean age 44.4 ± 22.2 years, 51 % male) who underwent CT of the abdomen and pelvis without intravenous contrast. Exclusion criteria included prior abdominal or spine surgery, active malignancy and scoliosis. CTs were reviewed and the attenuation of the rectus abdominis, transverse abdominis, internal and external obliques, psoas, multifidus, longissimus and gluteus maximus were measured bilaterally at consistent levels. Degenerative disc and bilateral facet joint disease were scored using established methods. Univariate analyses were performed using linear regression. Multivariate linear regression was performed to adjust for age, gender and BMI. RESULTS:CT density of each trunk muscle correlated inversely with age (p < 0.001) and BMI (p < 0.001). CT density of each trunk muscle correlated inversely with degenerative disc and facet joint disease in the univariate analyses (p < 0.001); however, only the gluteus maximus and the transverse abdominis remained significant predictors of degenerative disc and facet joint disease respectively in the multivariate analysis. CONCLUSION/CONCLUSIONS:Fatty infiltration of trunk musculature increases with age and BMI. Fatty infiltration of the gluteus maximus and transverse abdominis are associated with degenerative disc and facet joint disease, independent of age, gender and BMI.

OBJECTIVE:To determine abdominal adipose tissue parameters on PET/CT in patients with monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) that may serve as predictors of progression of MGUS to MM. We hypothesized that patients with MM had higher abdominal adiposity and higher fat metabolic activity compared to patients with MGUS. MATERIALS AND METHODS/METHODS:Our retrospective study was IRB approved and HIPAA compliant. The study group comprised 40 patients (mean age 64 ± 13 years) with MGUS and 32 patients (mean age 62 ± 10 years) with recently diagnosed MM (mean time since diagnosis of MM 3.0 ± 3.9 months) who had not undergone MM treatment. All patients underwent whole body FDG-PET/CT. Total abdominal adipose tissue (TAT), abdominal subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) cross sectional areas (CSA) (cm(2)) and metabolic activity (SUV) were assessed. Groups were compared using ANOVA. ROC curve analysis was performed to determine cutoff values for abdominal adipose tissue parameters to detect MM. RESULTS:Patients with recently diagnosed MM had higher TAT and SAT CSA (p ≤ 0.03) and higher fat metabolic activity (p < 0.01). VAT metabolic activity showed the highest sensitivity and specificity for identifying patients with MM (area under the curve 0.95 with cutoff value of >0.34, sensitivity 90.6 %, specificity 92.5 %, p < 0.0001). CONCLUSIONS:Patients who were recently diagnosed with MM had higher abdominal fat CSA and higher fat metabolic activity compared to patients with MGUS. These parameters may serve as novel biomarkers of progression of MGUS to MM.

OBJECTIVES: The Response Evaluation in Neurofibromatosis and Schwannomatosis (REiNS) International Collaboration Whole-Body MRI (WB-MRI) Working Group reviewed the existing literature on WB-MRI, an emerging technology for assessing disease in patients with neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2), and schwannomatosis (SWN), to recommend optimal image acquisition and analysis methods to enable WB-MRI as an endpoint in NF clinical trials. METHODS: A systematic process was used to review all published data about WB-MRI in NF syndromes to assess diagnostic accuracy, feasibility and reproducibility, and data about specific techniques for assessment of tumor burden, characterization of neoplasms, and response to therapy. RESULTS: WB-MRI at 1.5T or 3.0T is feasible for image acquisition. Short tau inversion recovery (STIR) sequence is used in all investigations to date, suggesting consensus about the utility of this sequence for detection of WB tumor burden in people with NF. There are insufficient data to support a consensus statement about the optimal imaging planes (axial vs coronal) or 2D vs 3D approaches. Functional imaging, although used in some NF studies, has not been systematically applied or evaluated. There are no comparative studies between regional vs WB-MRI or evaluations of WB-MRI reproducibility. CONCLUSIONS: WB-MRI is feasible for identifying tumors using both 1.5T and 3.0T systems. The STIR sequence is a core sequence. Additional investigation is needed to define the optimal approach for volumetric analysis, the reproducibility of WB-MRI in NF, and the diagnostic performance of WB-MRI vs regional MRI.