Publications

PURPOSE: Emergent spinal MRI is recommended for patients with back pain and red flags for infection. However, many of these studies are negative due to low prevalence of spinal infections. Our purpose was to assess if C-reactive protein (CRP) can be used to guide effective utilization of emergent MRI for spinal infections.

METHODS: 316/960 (33%) MRIs performed for infection by the emergency department over 75-month period had CRP levels obtained at presentation, after excluding patients receiving antibiotic or had spinal surgery in < 1 month. An MRI was considered positive when there was imaging evidence of spinal infection confirmed on follow-up by surgery/biopsy/drainage or definitive therapy. A CRP of ≤ 10 mg/L was considered normal and > 100 mg/L as highly elevated.

RESULTS: CRP was normal in 95/316 (30%) and abnormal in 221/316 (70%) patients. MRI was positive in 43/316 (13.6%) patients, all of whom had abnormal CRP. CRP (p < 0.001) and intravenous drug use (IVDU; p = 0.002) were independently associated with a positive MRI. Receiver operator characteristic (ROC) analysis showed AUC of 0.76 for CRP, slightly improving with IVDU. Sensitivity, specificity, and negative predictive values for CRP level cut-off: 10 mg/L, 100%, 35%, and 100%, and 100 mg/L, 58%, 70% and 91%, respectively.

CONCLUSION: Abnormal CRP, although extremely sensitive, lacks specificity in predicting a positive MRI for spinal infection unless highly elevated. However, a normal CRP (absent recent antibiotic or surgery) makes spinal infection unlikely, and its routine use as a screening test can help reducing utilization of emergent MRI for this purpose.

OBJECTIVES: The aims of the study were to systematically analyze causes for radiation dose outliers in emergency department noncontrast head computed tomographies (CTs), to develop and implement standardized system solutions, and audit program success for an extended period of time.

METHODS: This study was performed in a large, tertiary academic center between January 2015 and September 2017. Four phases of radiation dose data collection with and without prior interventions were performed. Outliers from 5 categories were evaluated for appropriateness in consensus by 2 radiologists and a senior CT technologist.

RESULTS: A total of 275 ± 15 CTs per period were included. Fifty-seven inappropriate scanning parameters were found in 24 (9%) of 254 CTs during the first analysis, 27 in 21 (7%) of 290 CTs during the second, 11 in 10 (4%) of 276 during the third assessment (P = 0.006). After a year without additional intervention, the number remained stable (14 in 11/281 CTs, 4%).

CONCLUSIONS: Combining a dose reporting system, individual case analysis, staff education, and implementation of systemic solutions lead to sustained radiation exposure improvement.

OBJECTIVE: The anterior thalamic nucleus (ATN) is a common target for deep brain stimulation (DBS) for the treatment of drug-refractory epilepsy. However, no atlas-based optimal DBS (active contacts) target within the ATN has been definitively identified. The object of this retrospective study was to analyze the relationship between the active contact location and seizure reduction to establish an atlas-based optimal target for ATN DBS.

METHODS: From among 25 patients who had undergone ATN DBS surgery for drug-resistant epilepsy between 2016 and 2018, those who had follow-up evaluations for more than 1 year were eligible for study inclusion. After an initial stimulation period of 6 months, patients were classified as responsive (≥ 50% median decrease in seizure frequency) or nonresponsive (< 50% median decrease in seizure frequency) to treatment. Stimulation parameters and/or active contact positions were adjusted in nonresponsive patients, and their responsiveness was monitored for at least 1 year. Postoperative CT scans were coregistered nonlinearly with preoperative MR images to determine the center coordinate and atlas-based anatomical localizations of all active contacts in the Montreal Neurological Institute (MNI) 152 space.

RESULTS: Nineteen patients with drug-resistant epilepsy were followed up for at least a year following bilateral DBS electrode implantation targeting the ATN. Active contacts located more adjacent to the center of gravity of the anterior half of the ATN volume, defined as the anterior center (AC), were associated with greater seizure reduction than those not in this location. Intriguingly, the initially nonresponsive patients could end up with much improved seizure reduction by adjusting the active contacts closer to the AC at the final postoperative follow-up.

CONCLUSIONS: Patients with stimulation targeting the AC may have a favorable seizure reduction. Moreover, the authors were able to obtain additional good outcomes after electrode repositioning in the initially nonresponsive patients. Purposeful and strategic trajectory planning to target this optimal region may predict favorable outcomes of ATN DBS.

BACKGROUND: Besides modeling/simulation-based analysis, no post-approval studies have evaluated the optimal administration frequency of pembrolizumab in non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS: We performed a multicenter retrospective cohort study to evaluate the association between survival outcomes and treatment extensions/delays of pembrolizumab-based regimens in patients with advanced NSCLC. Those who had received at least 4 cycles in routine practice were divided into 2 groups: nonstandard (Non-Std, ≥ 2 cycles at intervals > 3 weeks + 3 days) and standard (Std, all cycles every 3 weeks or 1 cycle > 3 weeks + 3 days).

RESULTS: Among 150 patients, 92 (61%) were eligible for the study (Non-Std, 27; Std, 65). The reasons for patients with extensions/delays in the Non-Std group included: immune-related adverse events (irAEs) (33%), non-irAE-related medical issues (26%), and patient-physician preference (41%). The Non-Std group was more likely to have a higher programmed death-ligand 1 tumor proportion score, a higher number of treatment cycles, and pembrolizumab monotherapy. Univariate and 6-month landmark analyses showed longer median overall survival and progression-free survival in the Non-Std group compared with the Std group. After multivariable adjustment for confounding factors, there was no significant difference in overall survival (hazard ratio, 1.2; 95% confidence interval, 0.3-4.8; P = .824) or progression-free survival (hazard ratio, 2.6; 95% confidence interval, 0.7-9.6; P = .157) between the 2 groups.

CONCLUSION: Our study shows that a significant proportion of patients with advanced NSCLC receive pembrolizumab-based regimens with extended intervals or delays in routine clinical practice and with similar outcomes to those receiving treatment at label-specified 3-week intervals. Given the durability of benefit seen and the potential for cost reduction and decreased infusion frequency in these patients, this requires validation in prospective trials.

BACKGROUND: Patient genetic polymorphism is associated with Crohn's clinical behavior; however, its association with magnetic resonance enterography (MRE) imaging appearance is not known.

PURPOSE: To analyze a set of known Crohn's disease (CD)-related single nucleotide polymorphisms for associations with MRE imaging phenotype and frequency of imaging.

STUDY TYPE: Retrospective.

POPULATION: 54 patients (mean age 40 years; 32 females and 22 males) with established CD from 2009 to 2016 who underwent baseline MRE and genetic testing for the presence of 168 single nucleotide polymorphisms (SNPs) potentially associated with inflammatory bowel disease.

FIELD STRENGTH/SEQUENCE: 1.5T or 3T clinical scanners, standard MRE clinical pulse sequences, including T2 -weighted single-shot fast spin echo, balanced steady-state free precession, T2 -weighted fast spin echo fat-suppressed, and T1 -weighted fat-suppressed pre- and postcontrast imaging.

ASSESSMENT: Three readers (all body imaging fellowship-trained radiologists) independently evaluated all imaging for the presence or absence of active disease and penetrating complications. Date of onset and frequency of endoscopies and cross-sectional imaging (CSI) were recorded. Disease behavior and distribution were categorized according to the Vienna and Montreal classifications, respectively.

STATISTICAL TESTS: Student's t-test and Fisher's exact test were used to assess significance of continuous and categorical variables, respectively. A hidden Markov model statistical knockoff approach was also applied for the analysis of genetic-imaging associations, with corrected P < 0.05 considered significant.

RESULTS: MRE demonstrated active bowel inflammation in 42 (78%) patients, strictures in 13 (28%), and fistulae in 13 (28%). The SNP rs1292053 (RBS6KB1) was highly associated with small bowel inflammation and luminal narrowing, with observed frequencies of association 0.66 and 0.39, respectively (P = 0.001). rs6062504 (Decoy receptor 3) was associated with lower age of onset (P = 0.012), higher proportion of early disease onset patients (P = 0.012), and higher average number of CSI/year (P = 0.014).

DATA CONCLUSION: This study demonstrated significant associations between CD genotype and MRE phenotype and frequency of cross-sectional imaging.

LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.

RATIONALE AND OBJECTIVES: Radiology participation is necessary in oncology multidisciplinary conferences (MDCs), but the resources required to do so are often unaccounted for. In this prospective study we provide an analysis of resource utilization as a function of outcomes for all MDCs covered by an entire radiology section and provide a time-based cost estimate.

MATERIALS AND METHODS: Following institutional review board approval, prospective data on all MDCs covered by abdominal radiologists at a single tertiary care academic center were obtained over nine weeks. A predefined questionnaire was used by a single observer who attended every imaging review and recorded the total time spent by the radiologists and several outcome measures. The total time recorded was used to provide a time-based cost estimate using a national salary survey.

RESULTS: Six radiologists participated in a total of 57 MDCs, with 577 cases reviewed and discussed. 181 (31%) cases were performed at outside facilities requiring full reinterpretation. Clinically significant revisions to original reports were recorded in 107 (18.5%) cases. Radiologist input directly resulted in alteration of cancer staging in 65 (11%) patients and specific recommendations for follow-up diagnostic workup in 280 (48%) of cases. The mean total time devoted by the staff radiologist per week to MDCs was 18.7 hours/week, nearly a half of full-time effort, or 8% of total effort per radiologist. The total annual projected cost of radiology coverage for each weekly MDC was $26,920.

CONCLUSION: Section-wide radiologist participation in MDCs directly resulted in change in clinical management in nearly half of reviewed cases. This was achieved at a notable time cost, highlighting the need for efficient integration of radiology MDC participation into radiologist workflow and compensation models.

OBJECTIVE. The purpose of this study was to determine the relationship between background parenchymal enhancement (BPE) on contrast-enhanced mammography (CEM) and breast tissue density, menstrual status, endocrine therapy, and risk factors for breast cancer and also to evaluate interreader agreement on classification of BPE on CEM. MATERIALS AND METHODS. Five subspecialty-trained breast radiologists independently and blindly graded tissue density (with fatty tissue and scattered fibroglandular tissue classified as nondense tissue and with heterogeneously dense and extremely dense classified as dense tissue) and BPE (with minimal or mild BPE categorized as low BPE and moderate or marked BPE categorized as high BPE) on CEM examinations performed from 2014 to 2018. Electronic medical charts were reviewed for information on menstrual status, endocrine therapy, history of breast surgery, and other risk factors for breast cancer. Comparisons were performed using the Kruskal-Wallis test, Mann-Whitney test, and Spearman rank correlation. Interreader agreement was estimated using the Fleiss kappa test. RESULTS. A total of 202 patients (mean [± SD] age, 54 ± 10 years; range, 25-84 years) underwent CEM. Tissue density was categorized as fatty in two patients (1%), scattered fibroglandular in 67 patients (33%), heterogeneously dense in 117 patients (58%), and extremely dense in 16 patients (8%). Among the 202 patients, BPE was minimal in 77 (38%), mild in 80 (40%), moderate in 31 (15%), and marked in 14 (7%). Dense breasts, younger age, premenopausal status, no history of endocrine therapy, and no history of breast cancer were significantly associated with high BPE. Among premenopausal patients, no association was found between BPE and time from last menstrual period to CEM. Overall interreader agreement on BPE was moderate (κ = 0.41; 95% CI, 0.40-0.42). Interreader agreement on tissue density was substantial (κ = 0.67; 95% CI, 0.66-0.69). CONCLUSION. Women with dense breasts, premenopausal status, and younger age are more likely to have greater BPE. Targeting CEM to the last menstrual period is not indicated.

Infections of the cardiovascular system may present with nonspecific symptoms, and it is common for patients to undergo multiple investigations to arrive at the diagnosis. Echocardiography is central to the diagnosis of endocarditis and pericarditis. However, cardiac computed tomography (CT) and magnetic resonance imaging also play an additive role in these diagnoses; in fact, magnetic resonance imaging is central to the diagnosis of myocarditis. Functional imaging (fluorine-18 fluorodeoxyglucose-positron emission tomography/CT and radiolabeled white blood cell single-photon emission computed tomography/CT) is useful in the diagnosis in prosthesis-related and disseminated infection. This pictorial review will detail the most commonly encountered cardiovascular bacterial and viral infections, including coronavirus disease-2019, in clinical practice and provide an evidence basis for the selection of each imaging modality in the investigation of native tissues and common prostheses.

PURPOSE: To evaluate diagnostic accuracy and clinical outcomes of patients with porcelain gallbladder (GB) diagnosed on CT.

MATERIALS AND METHODS: In this IRB-approved, HIPAA-compliant study, consecutive patients with porcelain gallbladder reported on CT between December 1, 2000 and August 31, 2017 in a tertiary academic center were included. Two radiologists independently reviewed CT images and confirmed presence of porcelain gallbladder. Discrepant cases were reviewed by a third reader with 15 years of experience in abdominal imaging. Porcelain gallbladder diagnosis was confirmed by surgery/pathology or follow-up imaging.

RESULTS: Porcelain gallbladder was reported in 133 CT studies. Radiologist review and pathology results confirmed porcelain gallbladder in 90/133 (68%) patients (age 71.6 ± 13.8 years, 57% female). One third (42/133; 32%) of CT reports were false positive; 1/133 (1%) remained indeterminate. Frequent pitfalls included: stones filling the whole gallbladder lumen in 39/43 (91%), sludge in 3/43 (7%) and mucosal enhancement in 2/43 (5%). In 5/90 (6%) patients, concurrent gallbladder cancer was noted on the initial CT scan. No patient developed subsequent gallbladder cancer during 6.6 ± 4.6 years of follow-up. One third (30/90, 33%) of patients with porcelain gallbladder have deceased during the follow-up period, all from unrelated causes.

CONCLUSION: At the time of presentation with porcelain gallbladder, 6% of patients had concurrent gallbladder cancer. No patient with porcelain gallbladder alone diagnosed on CT developed gallbladder cancer during a follow-up of 6.6 ± 4.6 years. Porcelain gallbladder is overcalled on CT, with frequent pitfalls including gallstones filling the whole gallbladder lumen, sludge, and wall enhancement.

Testosterone therapy (TT) is administered to enhance masculinization in transgender individuals. The long-term effect of exogenous testosterone on breast tissues remains unclear. Our study evaluated the modulation of breast morphology by TT in transgender individuals with special attention to duration of TT. We reviewed 447 breast surgical specimens from gender affirming chest-contouring surgery, and compared histopathological findings including degree of lobular atrophy, and atypical and non-atypical proliferations between subjects who did (n = 367) and did not (n = 79) receive TT. TT for one patient was unknown. TT for >12 months was associated with seven histopathological features. Longer duration of TT was significantly associated with higher degrees of lobular atrophy (p < 0.001). This relationship remained significant after accounting for age at surgery, ethnicity, body mass index, and presurgical oophorectomy (adjusted p < 0.001). Four types of lesions were more likely to be absent in breast tissues exposed to longer durations of TT: cysts (median = 16.2 months; p < 0.01; adjusted p = 0.01), fibroadenoma (median = 14.8 months; p = 0.02; adjusted p = 0.07), pseudoangiomatous stromal hyperplasia (median = 17.0 months; p < 0.001; adjusted p < 0.001), and papillomas (median = 14.7 months; p = 0.04; adjusted p = 0.20). Columnar cell change and mild inflammation were also less likely to occur in subjects receiving TT (p < 0.05), but were not linked to the duration of TT. Atypia and ductal carcinoma in situ were detected in 11 subjects (2.5%) all of whom received TT ranging from 10.1 to 64.1 months. The incidental findings of high-risk lesions and carcinoma as well as the risk of cancer in residual breast tissue after chest-contouring surgery warrant the consideration of culturally sensitive routine breast cancer screening protocols for transgender men and masculine-centered gender nonconforming individuals. Long-term follow-up studies and molecular investigations are needed to understand the breast cancer risk of transgender individuals who receive TT.