Can computed tomography replace or supplement autopsy?

Postmortem computed tomography (PMCT) has been integrated into the practice of many forensic pathologists. To evaluate the utility of PMCT in supplementing and/or supplanting medicolegal autopsy, we conducted a prospective double-blind comparison of abnormal findings reported by the autopsy pathologist with those reported by a radiologist reviewing the PMCT. We reviewed 890 cases: 167 with blunt force injury (BFI), 63 with pediatric trauma (under 5 years), 203 firearm injuries, and 457 drug poisoning deaths. Autopsy and radiology reports were coded using the Abbreviated Injury Scale and abnormal findings and cause of death (COD) were compared for congruence in consensus conferences with novel pathologists and radiologists. Overall sensitivity for recognizing abnormal findings was 71% for PMCT and 74.6% for autopsy. Sensitivities for PMCT/autopsy were 74%/73.1% for BFI, 61.5%/71.4% for pediatric trauma, 84.9%/83.7% for firearm injuries, and 56.5%/66.4% for drug poisoning deaths. COD assigned by reviewing PMCT/autopsy was correct in 88%/95.8% of BFI cases, 99%/99.5% of firearm fatalities, 82.5%/98.5% of pediatric trauma deaths, and 84%/100% of drug poisoning deaths of individuals younger than 50. Both autopsy and PMCT were imperfect in recognizing injuries. However, both methods identified the most important findings and are sufficient to establish COD in cases of BFI, pediatric trauma, firearm injuries and drug poisoning in individuals younger than 50. Ideally, all forensic pathologists would have access to a CT scanner and a consulting radiologist. This would allow a flexible approach that meets the diagnostic needs of each case and best serves decedents' families and other stakeholders.

The tangential view described by Moneim to demonstrate scapholunate dissociation: an update.

PURPOSE: Scapholunate dissociation is a common and significant injury to the wrist. Radiographs are important in the diagnosis of this injury and in the planning of treatment. The tangential radiograph view was described almost 40 years ago as a method for accurately measuring scapholunate gaps. The hand is positioned on a 20° foam rubber block and the thumb on the cassette, which positions the scaphoid and lunate articular surfaces parallel, without patient discomfort or effort. The goal of this study was to review this method with more recent data and in a larger group of patients. METHODS: Radiographs of 31 patients who had scapholunate interosseous ligament tears and surgical repair over a 9 year period were retrospectively evaluated. Each of the four authors independently measured scapholunate gaps for posteroanterior and tangential views. RESULTS: The tangential view gaps were significantly greater than the posteroanterior gaps overall. Similar results were found for borderline cases where the posteroanterior gap was less than 3 mm. Every tangential view gap measurement was greater than its respective posteroanterior gap with good inter-rater reliability. CONCLUSION: The tangential view is a reliable radiographic method to identify scapholunate gaps. It should be obtained when there is clinical concern for scapholunate dissociation, especially in patients with borderline posteroanterior gaps.

Magnetic resonance imaging of musculoskeletal infections.

Magnetic resonance imaging (MRI) is a powerful imaging modality in the evaluation of musculoskeletal (MSK) soft tissue, joint, and bone infections. It allows prompt diagnosis and assessment of the extent of disease, which permits timely treatment to optimize long-term clinical outcomes. MRI is highly sensitive and specific in detecting the common findings of MSK infections, such as superficial and deep soft tissue oedema, joint, bursal and tendon sheath effusions, lymphadenopathy, bone marrow oedema, erosive bone changes and periostitis, and bone and cartilage destruction and sequestration. Contrast-enhanced MRI allows detection of non-enhancing fluid collections and necrotic tissues, rim-enhancing abscesses, heterogeneously or diffusely enhancing phlegmons, and enhancing active synovitis. Diffusion-weighted imaging (DWI) is useful in detecting soft-tissue abscesses, particularly in patients who cannot receive gadolinium-based intravenous contrast. MRI is less sensitive than computed tomography (CT) in detecting soft-tissue gas. This article describes the pathophysiology of pyogenic MSK infections, including the route of contamination and common causative organisms, typical MR imaging findings of various soft tissue infections including cellulitis, superficial and deep fasciitis and necrotizing fasciitis, pyomyositis, infectious bursitis, infectious tenosynovitis, and infectious lymphadenitis, and of joint and bone infections including septic arthritis and osteomyelitis (acute, subacute, and chronic). The authors also discuss MRI findings and pitfalls related to infected hardware and diabetic foot infections, and briefly review standards of treatment of various pyogenic MSK infections.

Magnetic resonance imaging of rheumatological diseases.

Magnetic resonance imaging (MRI) is extremely useful in the early diagnosis of rheumatologic diseases, as well as in the monitoring of treatment response and disease progression to optimize long-term clinical outcomes. MRI is highly sensitive and specific in detecting the common findings in rheumatologic diseases, such as bone marrow oedema, cartilage disruption, articular erosions, joint effusions, bursal effusions, tendon sheath effusions, and synovitis. This imaging modality can demonstrate structural changes of cartilage and bone destruction years earlier than radiographs. Rheumatoid arthritis, crystal deposition diseases (including gouty arthropathy and calcium pyrophosphate deposition disease), seronegative spondyloarthropathies (including psoriatic arthritis, reactive arthritis, ankylosing spondylitis), and osteoarthritis have characteristic appearances on MRI. Contrast-enhanced MRI and diffusion-weighted imaging can provide additional evaluation of active synovitis. This article describes the MRI findings of normal joints, as well as the pathophysiological mechanisms and typical MRI findings of rheumatoid arthritis, gouty arthritis, calcium pyrophosphate deposition disease, psoriatic arthritis, reactive arthritis, ankylosing spondylitis, and osteoarthritis.

A comparison of ferumoxytol with gadolinium as contrast agents for the diagnostic magnetic resonance imaging of osteomyelitis.

BACKGROUND: Ferumoxytol, an FDA-approved superparamagnetic iron oxide nanoparticle (SPION) preparation used for the treatment of iron deficiency anemia, is also known to be taken up by macrophages in areas of infection or inflammation, where it produces negative contrast changes on T2-weighted MR images. PURPOSE: We sought to compare Ferumoxytol-induced MRI contrast changes with those observed using standard-of-care Gadolinium in patients presenting with symptoms suggestive of osteomyelitis. SUBJECTS: Out of eighteen enrolled patients, 15 had MR imaging with both ferumoxytol and gadolinium. Based on clinical and/or pathologic criteria, 7 patients were diagnosed with osteomyelitis, 5 patients had osteomyelitis ruled out, and in 3 patients a definitive diagnosis could not be made. FIELD STRENGTH: 1.5 Tesla. SEQUENCES: Used included STIR, T1-weighted and T2-weighted spin echo. ASSESSMENT: The mean contrast changes upon ferumoxytol and gadolinium administration were measured from lesion regions of interest and compared with control regions. STATISTICAL TESTS: Student's t-test, propagation of errors. Data are reported as means ± S.E. RESULTS: The mean contrast changes, ΔC, associated with a diagnosis of osteomyelitis were found to be ΔCFe = -2.7 ± 0.7 when Ferumoxytol and T2w imaging sequences were used and ΔCGd = +3.1 ± 1.1 (P < 0.001) when Gadolinium and a T1w imaging sequence was used. The MRI contrast changes for both agents correlated with systemic markers of inflammation, such as the erythrocyte sedimentation rate. In patients without osteomyelitis, no significant contrast changes were observed in T2-weighted, Ferumoxytol-contrasted MRI. The macrophages in osteomyelitic lesions were found to take up at least 16 times as much iron as benign bone marrow. DATA CONCLUSION: We conclude that in terms of its MRI diagnostic accuracy for osteomyelitis Ferumoxytol-contrasted MRI is a promising approach for diagnosing osteomyelitis that merits further study.

Awareness of implicit bias mitigates discrimination in radiology resident selection.

OBJECTIVES: Implicit bias is common and is thought to drive discriminatory behaviour. Having previously demonstrated discrimination against specific applicant demographics by academic radiology departments in a simulated resident selection process, the authors sought to better understand the relationship between implicit bias and discrimination, as well as the potential and mechanisms for their mitigation. METHODS: A total of 51 faculty reviewers at three academic radiology departments, who had participated in a 2017 audit study in which they were shown to treat applicants differently based on race or ethnicity and physical appearance, were invited to complete testing for implicit racial and weight bias using the Implicit Association Test in 2019. Respondents were also surveyed regarding awareness of their own personal racial and weight biases, as well as any prior participation in formal diversity training. Comparisons were made between implicit bias scores and applicant ratings, as well as between diversity training and self-awareness of bias. RESULTS: A total of 31 out of 51 faculty reviewers (61%) completed and submitted results of race and weight Implicit Association Tests. A total of 74% (23/31) reported implicit anti-obese bias, concordant with discrimination demonstrated in the resident selection simulation, in which obese applicants were rated 0.40 standard deviations (SDs) lower than non-obese applicants (P < .001). A total of 71% (22/31) reported implicit anti-Black bias, discordant with application ratings, which were 0.47 SDs higher for Black than for White applicants (P < .001). A total of 84% (26/31) of participants reported feeling self-aware of potential racial bias at the time of application review, significantly higher than the 23% (7/31) reporting self-awareness of potential anti-obese bias (P < .001). Participation in formal diversity training was not associated with implicit anti-Black or anti-fat bias, nor with self-reported awareness of potential racial or weight-based bias (all P > .2). CONCLUSIONS: These findings suggest that implicit bias, as measured by the Implicit Association Test, does not inevitably lead to discrimination, and that personal awareness of implicit biases may allow their mitigation.

Bias in Radiology Resident Selection: Do We Discriminate Against the Obese and Unattractive?

PURPOSE: To evaluate for appearance-based discrimination in the selection of radiology residents. METHOD: A deception study simulating the resident selection process examined the impact of attractiveness and obesity on resident selection. Seventy-four core faculty from 5 academic radiology departments reviewed mock residency applications in September and October 2017. Each application included demographic information and a photograph, representing a prespecified distribution of facial attractiveness and obesity, combined with randomized academic and supporting variables. Reviewers independently scored applications for interview desirability. Reviewer scores and application variables were compared using linear mixed fixed- and random-effects models. RESULTS: Reviewers evaluated 5,447 applications (mean: 74 applications per reviewer). United States Medical Licensing Examination Step 1 scores were the strongest predictor of reviewer rating (B = 0.35 [standard error (SE) = 0.029]). Applicant facial attractiveness strongly predicted rating (attractive vs unattractive, B = 0.30 [SE = 0.056]; neutral vs unattractive, B = 0.13 [SE = 0.028]). Less influential but still significant predictors included race/ethnicity (B = 0.25 [SE = 0.059]), preclinical class rank (B = 0.25 [SE = 0.040]), clinical clerkship grades (B = 0.23 [SE = 0.034]), Alpha Omega Alpha membership (B = 0.21 [SE = 0.032]), and obesity (vs not obese) (B = -0.14 [SE = 0.024]). CONCLUSIONS: Findings provide preliminary evidence of discrimination against facially unattractive and obese applicants in radiology resident selection. Obesity and attractiveness were as influential in applicant selection for interview as traditional medical school performance metrics. Selection committees should invoke strategies to detect and manage appearance-based bias.

Psychosocial and demographic factors influencing pain scores of patients with knee osteoarthritis.

BACKGROUND: Pain levels in patients with osteoarthritis (OA) of the knee are commonly assessed by using a numeric scoring system, but results may be influenced by factors other than the patient's actual physical discomfort or disease severity, including psychosocial and demographic variables. We examined the possible relation between knee-pain scores and several psychosocial, sociodemographic, disease, and treatment variables in 355 patients with knee OA. METHODS: The pain-evaluation instrument was a 0- to 10-point rating scale. Data obtained retrospectively from the patients' medical records were demographic characteristics, body mass index (BMI), concomitant disorders, illicit and prescription drug use, alcohol use, smoking, knee OA treatment, and severity of knee OA indicated by Kellgren-Lawrence (KL) radiographic grade. Univariate and multivariate analyses were performed to determine whether these variables correlated with reported pain scores. RESULTS: On univariate analysis, higher pain scores were significantly associated with Native American or Hispanic ethnicity; a higher BMI; current prescription for an opioid, antidepressant, or gabapentinoid medication; depression; diabetes mellitus; fibromyalgia; illicit drug use; lack of health insurance; smoking; previous knee injection; and recommendation by the clinician that the patient undergo knee surgery. Neither the patient's sex nor the KL grade showed a correlation. On multivariate analysis, depression, current opioid prescription, and Native American or Hispanic ethnicity retained a significant association with higher pain scores. CONCLUSIONS AND IMPLICATIONS: Our results in a large, ethnically diverse group of patients with knee OA suggest that psychosocial and sociodemographic factors may be important determinants of pain levels reported by patients with knee OA.

ACR Appropriateness Criteria® Stress (Fatigue/Insufficiency) Fracture, Including Sacrum, Excluding Other Vertebrae.

Stress fractures, including both fatigue and insufficiency types, are frequently encountered in clinical practice as a source of pain in both athletes and patients with predisposing conditions. Radiography is the imaging modality of choice for baseline diagnosis. MRI has greatly improved our ability to diagnose radiographically occult stress fractures. Tc-99m bone scan and CT may also be useful as diagnostic tools. Although fatigue and insufficiency fractures can be self-limited and go onto healing even without diagnosis, there is usually value in initiating prompt therapeutic measures as incomplete stress fractures have the potential of progressing to completion and requiring more invasive treatment or delay in return to activity. This is particularly important in the setting of stress fractures of the femoral neck. Accuracy in the identification of these injuries is also relevant because the differential diagnosis includes entities that would otherwise be treated significantly different (ie, osteoid osteoma, osteomyelitis, and metastasis). The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Iron-based superparamagnetic nanoparticle contrast agents for MRI of infection and inflammation.

OBJECTIVE. In this article, we summarize the progress to date on the use of superparamagnetic iron oxide nanoparticles (SPIONs) as contrast agents for MRI of inflammatory processes. CONCLUSION. Phagocytosis by macrophages of injected SPIONs results in a prolonged shortening of both T2 and T2* leading to hypointensity of macrophage-infiltrated tissues in contrast-enhanced MR images. SPIONs as contrast agents are therefore useful for the in vivo MRI detection of macrophage infiltration, and there is substantial research and clinical interest in the use of SPION-based contrast agents for MRI of infection and inflammation. This technique has been used to identify active infection in patients with septic arthritis and osteomyelitis; importantly, the MRI signal intensity of the tissue has been found to return to its unenhanced value on successful treatment of the infection. In SPION contrast-enhanced MRI of vascular inflammation, animal studies have shown decreased macrophage uptake in atherosclerotic plaques after treatment with statin drugs. Human studies have shown that both coronary and carotid plaques that take up SPIONs are more prone to rupture and that abdominal aneurysms with increased SPION uptake are more likely to grow. Studies of patients with multiple sclerosis suggest that MRI using SPIONs may have increased sensitivity over gadolinium for plaque detection. Finally, SPIONs have enabled the tracking and imaging of transplanted stem cells in a recipient host.

Lumbar spine spondylolysis in the adult population: using computed tomography to evaluate the possibility of adult onset lumbar spondylosis as a cause of back pain.

OBJECTIVE: To determine if new onset of low back pain in adults could be secondary to lumbar spondylolysis by establishing the age-related prevalence in the general population by examining patients undergoing computed tomography (CT) for reasons unrelated to back pain. MATERIALS AND METHODS: The records of 2,555 patients who had undergone abdominal and pelvic CT in 2008 were reviewed electronically. In order to determine a true representation of the general population, we reviewed all indications for CT, excluding patients with a primary complaint of low back pain as the primary indication for imaging. Equal numbers of patients were separated into age groups by decade to ensure an even distribution of ages for statistical analysis. Patients older than 70 years were grouped together to provide case numbers comparable to those of the other decades. Logistic regression analysis was performed to evaluate the significance of the results. Three board-certified radiologists, including two musculoskeletal fellows and a radiology resident, retrospectively evaluated CT scans for lumbar spondylolysis, including unilateral and bilateral defects. RESULTS: Of the 2,555 cases evaluated, there were 203 positive cases of defects of the lumbar pars interarticularis. This corresponded to an overall prevalence of 8.0%. Prevalence per decade was fairly evenly distributed and ranged from 7.0%( ages 30-39 years) to 9.2% (ages 70 years and above). Prevalence of ages 20-49 years was 7.9%, and that of ages 50 years and older was 8.0%. Male to female ratio was 1.5:1. Logistic regression showed no significant increase in spondylolysis based on age. CONCLUSION: No significant increase in the prevalence of lumbar spondylolysis was demonstrated in patients older than 20 years. This suggests that the development of symptomatic lumbar pars defects do not occur in this population and should not be considered as a rare but potentially treatable cause of new onset low back pain in adults. This study demonstrated an overall prevalence of pars defects of 8.0% in our population. As demonstrated in previous studies, the male to female ratio of 1.5:1 was a statistically significant difference.

New thoughts on the origin of Pellegrini-Stieda: the association of PCL injury and medial femoral epicondylar periosteal stripping.

OBJECTIVE: For the past 100 years, Pellegrini-Stieda disease has been described as calcification and ossification within the tibial collateral ligament, although these typical radiographic findings are often located more superior than the most proximal extent of the ligament. In this article, we demonstrate four magnetic resonance imaging cases of knee trauma with complete posterior cruciate ligament tear or avulsion, each demonstrating that injury to the medial collateral ligamentous complex can involve significant stripping of the tissue proximal to the medial epicondyle. CONCLUSION: Classic radiographic findings of Pellegrini-Stieda calcifications can be caused by stripping of the femoral periosteum proximal to the femoral attachment of the tibial collateral ligament, which appears to be associated with a complete posterior cruciate ligament injury.

Medial collateral ligament tear entrapped within a proximal tibial physeal separation: imaging findings and operative reduction.

Entrapped soft tissues such as periosteum and tendons have been described within joints and physeal fractures in the literature and frequently result in irreducible fractures and posttraumatic growth disturbances. We believe this case represents a novel presentation of acute, preoperative, magnetic resonance (MR) imaging diagnosis of a torn medial collateral ligament entrapped within a proximal tibial physeal separation. This case is presented with MR imaging and operative correlation of the findings.

Extensor hallucis capsularis: frequency and identification on MRI.

BACKGROUND: The extensor hallucis capsularis (EHC) is the most common name given to the accessory tendon sporadically seen medial to the extensor hallucis longus (EHL). We performed cadaver dissections and MRI evaluation to determine the frequency of its occurrence, the pattern of its origin and insertion, and its potential suitability as tendon graft. METHODS: The EHC was examined by dissection in 81 cadaver feet. Physical parameters pertaining to EHC size and location were recorded. MRI was performed on six cadaver legs to determine if the EHC can be identified radiographically. MRI images were evaluated independently by a foot and ankle specialist and a radiologist. RESULTS: The EHC was present in 71 (88%) of the specimens. It originated from the EHL tendon or muscle in 93% and inserted into the first metatarsophalangeal joint capsule in 99% of cases. All EHC tendons were less than or equal to 4 mm in width; only 16% were more than 2 mm wide. Correct prediction of the presence or absence of EHC by MRI varied according to EHC width: two of two in tendons more than 2 mm, five of eight in tendons 1 to 2 mm, and zero of two in tendons 1 mm or less. CONCLUSION: Up to 14% of the population may have an EHC tendon suitable for grafting in reconstructive surgeries, particularly surgeries related to hallux dysfunction. MRI may have a role in the preoperative identification of the EHC.