The utility of whole spine survey MRI in blunt trauma patients sustaining single level or contiguous spinal fractures.

PURPOSE: To determine the utility of obtaining whole-spine survey MRI after a whole-spine CT diagnoses single level or contiguous fractures. METHODS: A retrospective search from 2015 to 2017 was performed using an institutional PACS database for consecutive patients who sustained spinal fractures from blunt injury. Only patients who received whole-spine CT followed by whole-spine MRI were included in the study. All cases had sagittal T2-weighted and Short TI (Tau) inversion recovery (STIR) imaging of the entire spine with additional T1 and T2-weighted axial imaging covering the known injury. Reports from the whole-spine CTs were compared to the reports of the whole-spine MRI to determine if additional bony and soft tissue injury were identified on subsequent MRI. RESULTS: A total of 156 patients met the inclusion criteria, with an average age of 59.5 ± 20.6 years. Twenty-nine patients (18.5%) had a whole-spine MRI that demonstrated an additional bony ± soft tissue injury. A 95.1% of the additional injuries were osseous contusions or vertebral body compression fractures without significant loss of height. The distance between the original injury on CT and the additional injury on MR ranged from 1 to 13 vertebrae. A 82.8% of the additional injuries occurred within 1 to 8 vertebrae levels of the primary injury and most commonly in the thoracic spine. CONCLUSIONS: Most additional bony injuries detected on MRI are bone contusions and mild compression fractures, which are unlikely to alter management. However, if screening MRI is performed for additional bony injuries, we posit that a targeted regional spinal MRI is adequate.

Second opinions in orthopedic oncology imaging: can fellowship training reduce clinically significant discrepancies?

OBJECTIVE: To determine factors that lead to significant discrepancies in second-opinion consultation of orthopedic oncology patients, and particularly if musculoskeletal fellowship training can decrease clinically significant discrepancies. METHODS: A PACS database was queried for secondary reads on outside cross-sectional imaging studies, as requested by orthopedic oncology from 2014 to 2017. Comparison of original and secondary reports was performed using a published seven-point scale that defines clinically significant discrepancies. An online search was performed for each original radiologist to record if a fellowship in musculoskeletal imaging was completed. Additionally, years of post-residency experience, number of Medicare part B patients billed per year (marker of practice volume), and average hierarchical condition category for each radiologist (marker of practice complexity) was recorded. RESULTS: A total of 571 patients met the inclusion criteria, with 184 cases initially interpreted by an outside fellowship trained musculoskeletal (MSK) radiologist and 387 cases initially interpreted by a non-MSK trained radiologist. The rate of clinically significant discrepancy was 9.2% when initially interpreted by MSK radiologists compared with 27.9% when initially performed by non-MSK radiologists (p < 0.05). After adjustment by both patient characteristics and radiologist characteristics, the likelihood of clinically significant discrepancies was greater for initial interpretations by non-MSK radiologists compared with MSK radiologists (OR = 1.36; 95% CI = 1.23-2.49). CONCLUSION: In orthopedic oncology patients, the rate of clinically significant discrepancies was significantly higher when initially interpreted by non-MSK radiologists compared with MSK radiologists. The lower rate of clinically significant discrepancies demonstrates that subspecialty training may direct more appropriate diagnosis and treatment.

Providing Value-Based Service to a Sprawling Orthopaedics Practice.

Health care in the United States is changing, and diagnostic radiology is attempting to adapt to the new norm. A view of the landscape shows mergers, acquisitions, and radiology practices becoming larger. Musculoskeletal (MSK) radiology is trending toward subspecialization, and orthopaedic surgery practices are demanding quality, convenience, and efficiency in imaging services. In other industries, optimization of operations and strategic deployment of resources are standard, but radiology is not quite there yet. This article details our opportunities in MSK imaging to increase market share through service, added value, and improved operational efficiency.

Unsuspected pheochromocytoma incidentally found on chest CT.

A 51-year-old woman with history of migraine headaches and intermittent nausea, vomiting, palpitations, and diaphoresis presented to the emergency department with hypertensive emergency 1 month after starting a beta blocker for migraine prophylaxis. Contrast-enhanced computed tomography of the chest incidentally revealed a large abdominal mass in the area of the left adrenal gland. Iodine-123 metaiodobenzylguanidine scan imaging showed localized uptake into the left adrenal gland. Along with imaging results, laboratory testing confirmed the diagnosis of pheochromocytoma. The patient was treated with blood pressure control, specifically alpha blockade, and surgical excision of the mass. This case displays a typical clinical presentation of pheochromocytoma coupled with atypical radiographic size and appearance.

Outcomes after Motor Vehicle Trauma: Transfers to Level I Trauma Centers Compared with Direct Admissions.

BACKGROUND: The multilevel designation system given to U.S. trauma centers has proven useful in providing injury-level-appropriate care and guiding field triage. Despite the system, patients are often transferred to Level I trauma centers for higher-level care/specialized services. OBJECTIVES: The objective of this study is to assess whether there is a difference in outcomes of patients transferred to Level I centers compared with direct admissions. METHODS: The Nationwide Inpatient Sample was queried to identify patients involved in motor vehicle accidents, using International Classification of Diseases, Ninth Revision, Clinical Modification E-codes. Patients that were admitted to Level I trauma centers were identified using American College of Surgeons or American Trauma Society designations. RESULTS: There were 343,868 patients that met inclusion criteria. Of these patients, 29.2% (100,297) were admitted to Level I trauma centers, 5.7% (5691) of which were identified as trauma transfers. The lead admitting diagnosis for transfers was pelvic fracture (11.5%). Caucasians were 2.62 times as likely to be transferred as African-Americans (confidence interval 2.32-2.97), and 3.71 times as likely as Hispanics (confidence interval 3.25-4.23). Despite transfer patients having higher adjusted severity scores and higher adjusted risk of mortality, there were no differences in mortality (p = 0.95). CONCLUSIONS: Nationally, trauma transfers do not have an increase in mortality when compared with directly admitted patients, despite a higher adjusted severity of illness and higher adjusted risk of mortality.

Resident Perspectives of an Interactive Case Review Following Independent Didactic Study as a Method of Teaching a Pediatric Imaging Curriculum.

PURPOSE: The ABR has recently changed the format of the board examination, in which the oral examination was replaced by a computer based multiple-choice test. The purpose of this study was to determine resident's perceptions of a new conference resembling the new ABR format. METHODS: Residents were requested to review a series of didactic pediatric imaging presentations prior to attending case conference. During conference, unknown cases reflecting the subject matter from the didactic presentations were presented along with multiple-choice questions. We then surveyed resident perspectives after each case conference. RESULTS: Between 14 and 18 residents were surveyed at the end of each subspecialty case review presentation. About 94% of resident respondents felt that the independent didactic study followed by an interactive case review session would better prepare them for the ABR certification exams, compared to didactic lectures alone. Furthermore, 95% of the respondents indicated that they preferred the independent didactic review followed by interactive case review versus didactic lecture alone. Most the respondents (85%) felt that combining independent didactic review with interactive unknown case sessions made the material more interesting and provided greater understanding of the material. There was no statistically significant difference in the distribution of answers across the subspecialty sessions (p > .05). CONCLUSION: Radiology residents favorably reviewed the combination of independent review of didactic material prior to interactive case review. Material presented in this fashion is felt to be more interesting and is thought to result in enhanced understanding of pediatric radiology material.

Clinical Impact of Second-Opinion Musculoskeletal Subspecialty Interpretations During a Multidisciplinary Orthopedic Oncology Conference.

PURPOSE: To analyze the impact on clinical management when musculoskeletal radiologists render second-opinion consultations during multidisciplinary orthopedic oncology conference. METHODS: A PACS database was searched for secondary interpretations on outside MRI studies reviewed during a multidisciplinary orthopedic oncology conference from January 2014 to December 2016. Reports were compared with the original interpretations, when available. Reports were categorized using a 7-point scale: I (no discrepancy), II (undetected clinically insignificant abnormality), III (clinically insignificant difference in interpretation), IV (difference in imaging follow-up recommendation), V (equivocal initial interpretation with subsequent definitive subspecialty interpretation), VI (clinically significant difference in interpretation), VII (failure to detect a clinically significant abnormality). RESULTS: A total of 409 patients met inclusion criteria, with an average age of 47.9 ± 19.2. There were 91 (22.2%) instances of discrepant interpretations resulting in clinically significant differences in management; 67 (16.4%) were category VI and 24 (5.9%) were category VII. An additional 72 subjects (17.6%) were identified as category IV and 28 (6.8%) as category V, yielding at total of 191 (46.7%) clinically relevant discrepancies. When pathology was available, the secondary consultations were concordant in 57 of 61 cases (93.4%) and the outside interpretations were concordant in 39 of 61 cases (63.9%, P < .05). CONCLUSION: A 22.2% rate of clinically significant difference was observed between primary and secondary interpretations. The substantial rate of clinically relevant discrepancies demonstrates that subspecialty expertise often changed the primary diagnosis. Thus, by participating in a multidisciplinary team, subspecialty radiologists have a unique opportunity to help direct appropriate treatment plans.

Imaging of the thoracic and lumbar spine in a high volume level 1 trauma center: are reformatted images of the spine essential for screening in blunt trauma?

Reformatted CTs of the thoracic and lumbar spine (CT T/L) from CTs of the chest, abdomen, and pelvis (CT body) may be performed for screening the thoracolumbar spine in patients sustaining blunt trauma. The purpose of this study was to determine whether there was a difference in the rate of detection of spinal fractures on CTs of the body compared to the reformatted T/L spine. A secondary endpoint was to evaluate whether cases dictated by trainees improved fracture detection rate. We reviewed the records of 250 consecutive blunt trauma patients that received CTs of the chest, abdomen, and pelvis (CT body) with concurrent CT T/L reformats. Each report was reviewed to determine if there was a thoracolumbar fracture and whether a trainee had been involved in interpreting the CT body. If a fracture was identified on either report, then the number, type, and location of each fracture was documented. Sixty-nine fractures, from a total of 38 patients, were identified on either the CT of the body or the CT T/L. Sensitivity for CT body interpretations was 94 % (95 % CI: 86-98 %) compared to a 97 % (95 % CI: 89-100 %) sensitivity for the CT T/L (p > 0.5). Although the sensitivity was 97 % (95 % CI: 88-100 %) when a trainee was involved in interpreting the body CT, there was no statistically significant improvement. The results suggest that with careful scrutiny most spine fractures can be diagnosed on body CT images without the addition of spine reformats. The most commonly missed finding is an isolated non-displaced transverse process fracture, which does not require surgical intervention and does not alter clinical management. The results suggest that thin section reformats do not need to be routinely ordered in screening blunt trauma patients, unless a bony abnormality is identified on the thicker section body CT images.

Gas-phase studies of substrates for the DNA mismatch repair enzyme MutY.

The gas-phase thermochemical properties (tautomeric energies, acidity, and proton affinity) have been measured and calculated for adenine and six adenine analogues that were designed to test features of the catalytic mechanism used by the adenine glycosylase MutY. The gas-phase intrinsic properties are correlated to possible excision mechanisms and MutY excision rates to gain insight into the MutY mechanism. The data support a mechanism involving protonation at N7 and hydrogen bonding to N3 of adenine. We also explored the acid-catalyzed (non-enzymatic) depurination of these substrates, which appears to follow a different mechanism than that employed by MutY, which we elucidate using calculations.

Theoretical studies of the quinolinic acid to nicotinic acid mononucleotide transformation.

Quinolinate phosphoribosyl transferase (QPRTase) is an essential enzyme that catalyzes the transformation of quinolinic acid (QA) to nicotinic acid mononucleotide (NAMN), a key step on the de novo pathway for nicotinamide adenine dinucleotide (NAD) biosynthesis. We describe herein a theoretical study of the intrinsic energetics associated with the possible mechanistic pathways by which QA forms NAMN. Our main interest is in probing the decarboxylation step, which is intriguing since the product is a vinylic anion, not unlike the reaction catalyzed by orotidine 5'-monophosphate (OMP) decarboxylase, an enzyme whose mechanism is under fierce debate. Our calculations indicate that a path involving a quinolinic acid mononucleotide (QAMN) intermediate is the most energetically attractive, favoring decarboxylation. We also find that the monocarboxylate form of QAMN will decarboxylate much more favorably energetically than will the dicarboxylate form of QAMN. Furthermore, our calculations indicate that decarboxylation is not a likely first step; the substrate in such a mechanism would prefer to decarboxylate at the C3 position, not the desired C2 position. We also discuss our results in the context of existing experimental data.