Anil Chauhan

MR Characterization of Focal Liver Lesions: Pearls and Pitfalls

Magnetic resonance (MR) can characterize specific tissue subtypes, thus facilitating focal liver lesion diagnosis. Focal liver lesions that are isointense to hyperintense to liver on T1-weighted images are usually hepatocellular in origin. Chemical shift imaging can narrow the differential diagnosis by detecting the presence of lipid or iron. T2 and heavily T2-weigthed fast spin echo imaging can differentiate solid from nonsolid focal liver lesions. The authors illustrate these MR imaging pearls and the uncommon exceptions (pitfalls). The authors hope that you will find this less traditional contribution to the Magnetic Resonance Clinics of North America helpful in clinical practice.

Overview of Conventional Imaging-based Intervention in Clinical Practice

This article presents an overview of image-guided interventions using conventionally available imaging modalities. It discusses technical and clinical aspects of the interventions, and also focuses on site-specific biopsies such as liver, spleen, renal, and soft tissue biopsies in the abdomen. It briefly discusses the emerging role of PET imaging and other technologies that will improve the diagnostic yield of image-guided biopsies.

Diagnostic accuracy of hepatorenal index in the detection and grading of hepatic steatosis

The objectives of our study were to assess the accuracy of hepatorenal index (HRI) in detection and grading of hepatic steatosis and to evaluate various factors that can affect the HRI measurement.

Tumor Thrombus as a Rare Presentation of Lymphoma: A Case Series of 14 Patients

OBJECTIVE We present a case series of 14 patients with lymphoma presenting with tumor thrombus to highlight this rare but important manifestation of lymphoma. CONCLUSION The dominant mass leading to tumor thrombus formation was nodal disease in nine patients and extranodal disease in five patients. Lymphoma should be considered in the differential diagnosis in the setting of tumor thrombus with solid organ involvement when there are other imaging features suggestive of lymphoma.

Can abdominal computed tomography imaging help accurately identify a dedifferentiated component in a well-differentiated liposarcoma?

Purpose To assess the ability of computed tomography (CT) to differentiate an atypical lipomatous tumor/well-differentiated liposarcoma (WDLPS) from a WDLPS with a dedifferentiated component (DDLPS) within it. Materials and Methods Forty-nine untreated patients with abdominal atypical lipomatous tumors/well-differentiated liposarcomas who had undergone contrast-enhanced CT were identified using an institutional database. Three radiologists who were blinded to the pathology findings evaluated all the images independently to determine whether a dedifferentiated component was present within the WDLPS. The CT images were evaluated for fat content (⩽25% or >25%); presence of ground-glass density, enhancing and/or necrotic nodules; presence of a capsule surrounding the mass; septations; and presence and pattern of calcifications. A multivariate logistic regression model with generalized estimating equations was used to correlate imaging features with pathology findings. Kappa statistics were calculated to assess agreement between the three radiologists. Results On the basis of pathological findings, 12 patients had been diagnosed with DDLPS within a WDLPS and 37 had been diagnosed with WDLPS. The presence of an enhancing or a centrally necrotic nodule within the atypical lipomatous tumor was associated with dedifferentiated liposarcoma (P = 0.02 and P = 0.0003, respectively). The three readers showed almost perfect agreement in overall diagnosis (&kgr; r = 0.83; 95% confidence interval, 0.67–0.99). Conclusions An enhancing or centrally necrotic nodule may be indicative of a dedifferentiated component in well-differentiated liposarcoma. Ground-glass density nodules may not be indicative of dedifferentiation.

Introducing First-Year Radiology Residents to the ACR at the AMCLC from 2009 to 2013: Summary of Experiences and Five-Year First-Cohort Follow-Up

PURPOSE The aim of this report is to provide a five-year summary of the Minnesota Radiological Societys initiative to send first-year radiology residents to the ACR at the AMCLC. The authors provide an update of the survey data for the first five years (2009-2013) and a report of the ACR membership status of the original 2009 cohort (class of 2012) five years after their conference experience. METHODS Participating residents from 2009 to 2013 completed pre- and postconference surveys assessing their knowledge of ACR-related topics, conference satisfaction, and intention to join the ACR. ACR membership status of the first cohort was determined using the ACR membership database and compared with both the previous five graduating classes and the national average for practicing radiologists. RESULTS Seventy first-year Minnesota radiology residents attended the conference from 2009 to 2013. Knowledge of the ACR significantly increased after the conference. Most residents were highly satisfied or satisfied with their conference experience and highly likely or likely to join the ACR in the future. Two years after residency, 87% of the first cohort (13 of 15) were ACR members, compared with an average membership rate of 57% (63 of 110) for the previous five graduating classes. CONCLUSIONS Exposing radiology residents early to the ACR at the AMCLC leads to a significant increase in knowledge pertaining to the professional organization. This exposure likely leads to increased ACR membership when residents enter practice. This early engagement in radiology affairs can lead to a higher rate of ACR membership and to a better informed membership.

Fat-containing hypermetabolic masses on FDG PET/CT: A spectrum of benign and malignant conditions

OBJECTIVE This article focuses on identifying the imaging appearances of hypermetabolic fatty masses and masslike lesions on PET/CT and understanding the diagnostic challenges radiologists may face while interpreting findings of these lesions on PET/CT. This article provides an approach to aid in the diagnosis of these lesions and the appropriate management of patients. CONCLUSION Both malignant and benign fat-containing masses and masslike lesions can show hypermetabolic activity on PET/CT. Although the differential diagnosis is broad, clinical history, anatomic location, and knowledge of anatomic variants and imaging features can help radiologists avoid misinterpretation of benign fatty lesions as malignancy.

Application of ARFI-SWV in Stiffness Measurement of the Abdominal Wall Musculature: A Pilot Feasibility Study

The purpose of this study was to assess the feasibility of acoustic radiation force impulse shear wave velocity and textural features for characterizing abdominal wall musculature and to identify subject-related and technique-related factors that can potentially affect measurements. Median shear wave velocity measurements for the right external abdominal oblique were the same (1.89 ± 0.16 m/s) for both the active group (healthy volunteers with active lifestyles) and the control group (age and body mass index-matched volunteers from an ongoing hernia study). When corrected for thickness, the ratio of right external abdominal oblique shear wave velocity -to-muscle thickness was significantly higher in the control group than in the active volunteers (4.33 s-1 versus 2.88 s-1; p value 0.006). From the textural features studied for right external abdominal oblique, 8 features were found to be statistically different between the active and control groups. In conclusion, shear wave velocity is a feasible and reliable technique to evaluate the stiffness of the abdominal wall musculature. Sonographic texture features add additional characterization of abdominal wall musculature.

Role of ultrasound in complications of hematopoetic stem cell transplantation

Abstract Hematopoetic stem cell transplantation (HSCT) is an established therapeutic option for both malignant and nonmalignant indications, whose incidence has continued to increase in recent years. Because of its lower cost and lack of radiation exposure, ultrasound examination is often the first-line imaging modality in evaluating patients both before and after HSCT. It is important for radiologists to be aware of sonographic manifestations of the complications that may arise from HSCT. In this study, we will review the basics of HSCT, the role of imaging, and ultrasound examination findings in common and uncommon complications arising from HSCT.

Reply to “Intravascular Lymphoma”

AJR 2015; 205:W388 0361–803X/15/2053–W388