The effect of gadolinium-based intravenous contrast in the initial characterization of musculoskeletal soft tissue tumors.

OBJECTIVE: To determine if gadolinium-based contrast agents increase the sensitivity, specificity or reader confidence of malignant potential in musculoskeletal soft tissue tumors. METHODS: Pre- and post-contrast MRI studies from 87 patients were read by three independent radiologists of different experience. Readers noted malignant potential and confidence in their diagnosis based on pre-contrast and post-contrast MRI studies. Statistical models assessed for agreement between MRI reader diagnosis and pathologic results as well as analyzing effects of contrast on reader confidence. Inter- and intra-observer variabilities of malignant potential were also calculated. RESULTS: 87 patients (48 benign and 39 malignant; mean [± SD] age 51 ± 17.9 and 57.1 ± 17.1, respectively) were evaluated. For all readers, pre-contrast and post-contrast sensitivities were 68.1 % and 70.6 % while pre-contrast and post-contrast specificities were 84.6 % and 83.8 %, respectively without significant change (p=0.88). There was not a significant association with the use of contrast and prediction of malignant potential with or without the resident reader (p=0.65 and p=0.82). Use of contrast was significantly associated with higher levels of reader confidence (p=0.02) for all readers. Inter- and intra-observer variabilities were in good agreement (W = 0.77 and 0.70). CONCLUSION: The addition of a post-contrast sequence increased reader confidence in their diagnosis without a corresponding significant increase in accurate prediction of malignant potential.

What Do Program and Geographic Preference Signals Signal? A Survey of Diagnostic Radiology and Integrated Interventional Radiology Residency Applicants.

RATIONALE AND OBJECTIVES: As part of the 2022-2023 Diagnostic/Interventional Radiology residency application process, applicants could participate in the ERAS supplemental application, including sending up to six preference signals and three geographic signals. Our goal was to survey Diagnostic Radiology and Integrated Interventional Radiology applicants at two large academic institutions in different geographic locations regarding their perceived impact of program and geographic preference signaling on the application process. METHODS: An anonymous survey was sent to 282 applicants between two academic medical centers asking about their participation in program and geographic preference signaling as well as their perception on its impact on the application process. RESULTS: 105 applicants responded to the survey (37.2% [105/282]). Most applicants (26% [27/102]) received four interviews from signaled programs. When prompted to best describe their sentiments with respect to program signaling (one being most negative and five being most positive), the plurality of applicants reported a positive sentiment of four (36% [37/103]). Applicants that received four to six interviews from signaled programs were significantly more likely to feel positively towards program signaling than those that received one to three interviews (p = 0.01). Geography was the most important deciding factor on which programs to signal for applicants (57% [58/101]). DISCUSSION: Our survey results demonstrate that most applicants felt positively towards program signaling and it increased their odds of receiving interviews from preferred programs, which is consistent with the current literature. CONCLUSION: Program and geographic signaling are relatively new features of the ERAS residency application process and therefore, their effects on the match outcome are still in question. However, our study results indicate that they are perceived positively by most applicants and that they boost their chances in finding their ideal match.

Asymptomatic Intracardiac Cement Embolism Following Kyphoplasty.

Cement extravasation can occur during vertebral body augmentation such as kyphoplasty and vertebroplasty with diverse presentation and resultant treatment. The cement can embolize through venous vasculature to the thorax where it poses a potential threat to the cardiovascular and pulmonary systems. A thorough risk-benefit analysis should be conducted to select the appropriate treatment course. We present an asymptomatic case of cement extravasation to the heart and lungs during kyphoplasty.

The effect of virtual interviews on the musculoskeletal radiology fellowship match.

OBJECTIVE: Resulting from the COVID-19 pandemic, a virtual interview format was adopted in lieu of in-person interviews for fellowship recruitment. The purpose of this study is to analyze the potential effect that virtual interviews have on musculoskeletal radiology fellowship match results and collect opinions of the process. MATERIALS AND METHODS: An anonymous survey was sent to 87 listed US-based musculoskeletal radiology fellowship directors, who were asked for their 2019-2020 and 2020-2021 match data: fellowship positions, interviewees, ranked interviewees, and matched ranks. They rated effectiveness of virtual interviews on a ten-point scale (1 poor-10 excellent) and provided an ideal percentage of future interviews to be conducted virtually. RESULTS: Thirty responses were received (34.4% response rate). Primary analysis found significant increase in the mean number of candidates ranked in 2020-2021, 14.6 to 17.5 (p = 0.047). The mean rank of matched applicants increased from 6.02 to 6.43, without significance (p = 0.821). Secondary analysis, which attempted to exclude internally matched programs, found significant increases in 2020-2021 in the mean number of applicants-28.7 to 32.4 (p = 0.017), interviews conducted-17.8 to 21.3 (p = 0.007), and candidates ranked by programs-16.3 to 19.8 (p = 0.015). The mean rank of matched applicants increased from 6.39 to 7.03, without significance (p = 0.713). CONCLUSION: With results showing an increase in applications, interviews conducted, and ranked applicants while lowering the average rank of matched candidates, musculoskeletal radiology fellowship directors should consider interviewing more applicants than they usually would in the prior in-person recruitment format.

Intra-articular Osteoid Osteoma of the Olecranon Fossa.

Osteoid osteomas are benign primary bone lesions characterized by a central nidus with surrounding reactive sclerosis, classically presenting as worsening nocturnal pain relieved by non-steroidal anti-inflammatory medications (NSAIDs). These most commonly occur in intracortical bone and the diaphysis of long bones. As a rare entity, intra-articular osteoid osteomas present unusually, often resulting in a delayed or incorrect diagnosis. We present a case of an intra-articular osteoid osteoma, emphasizing the importance of MRI in aiding diagnosis in this atypical location.

MR Imaging of Knee Cartilage Injury and Repair Surgeries.

Cartilage injuries are common and may predispose to early accelerated osteoarthritis. Magnetic resonance (MR) imaging is critical in the detection and characterization of acute and chronic cartilage injuries. Several surgical approaches including microfracture, osteochondral allografting, autologous osteochondral transfer system, and autologous chondrocyte implantation have been developed to treat cartilage lesions. The goals of these treatments include relief of symptoms, restoration of joint function, and delay of progression of osteoarthritis. Imaging evaluation by MR imaging plays a crucial role in diagnosis and surgical planning as well as monitoring for postoperative complications.

The Everted Acetabular Labrum: Patho-anatomy, Magnetic Resonance Imaging and Arthroscopic Findings of a Native Variant.

PURPOSE: The purpose of this study was to introduce a native labral variant, the everted acetabular labrum, and to describe the patho-anatomy, magnetic resonance imaging and magnetic resonance arthrogram (MRI/MRA) characteristics and the arthroscopic findings in this condition. METHODS: All primary hip arthroscopy procedures performed by the senior author between June 2013 and January 2020 were reviewed retrospectively. An everted acetabular labrum was identified as a segment of labrum that lacked apposition to the femoral head with the hip off traction. All everted labra were treated with labral advancement and repair with or without augmentation or reconstruction. The labrum-to-femoral head distance was measured in 3T MRI/MRA at the 1-2 o'clock position. A random selection of 38 hips without an everted labrum served as controls to compare radiographic parameters. RESULTS: A total of 68 hips were identified as having an everted labrum during the study period (mean age, 29.1 years), and 55 hips had advanced imaging available for review. MRI/MRA scans revealed the everted labrum to have a triangular shape in 17 hips (31%) and a blunted/round shape in 38 hips (69%), which differed significantly from controls (triangular 25/38 [66%], blunted 13/38 [34%], P < 0.001). The average labrum-to-femoral head distance was 1.4 mm for everted labra versus 0.0 mm for controls (P < 0.0001) and the mean labral lengths and widths were significantly shorter than those of controls (both P < 0.01). Of the hips, 8 underwent labral reconstruction or augmentation, and 61 underwent labral advancement/repair. CONCLUSION: The everted acetabular labrum is a native variant that is identifiable during hip arthroscopy by assessing the labral seal off traction. Preoperative MRI/MRA findings can be highly predictive of an everted labrum. Surgical treatment includes labral advancement and repair or reconstruction to restore contact between the labrum and the femoral head. LEVEL OF EVIDENCE: III, retrospective comparative study.

Evaluating bone biopsy quality by technique in an animal model.

Rationale and Objectives: Powered bone biopsy technique is popular due to its ease of use. However, there is conflicting evidence regarding the diagnostic quality of the samples. The purpose of this study is to evaluate the diagnostic adequacy of different bone biopsy devices and techniques as it relates to the frequency of sample artifacts. Materials and Methods: Bone biopsy was performed on same-day processed lamb femora using the following techniques: manual, pulsed powered and full powered. Ten samples were collected using each method by a single musculoskeletal-trained radiologist and were reviewed by 3 blinded pathologists. Samples were compared across multiple categories: length, bone dust, thermal/crush artifact, cellular morphology, fragmentation, and diagnostic acceptability. Bayesian Multilevel Nonlinear Regression models were performed assessing the association between the techniques across the categories. Results: Statistical analysis revealed that the manual technique outperformed any powered technique across all categories: decreased thermal/crush artifact (P = 0.014), decreased bone dust (p<0.001), better cellular morphology (P = 0.005), less fragmentation (P < 0.0001) and better diagnostic acceptability (P < 0.0001). Conclusion: Manually obtained bone biopsy samples generally produce a more diagnostic sample as compared to powered techniques in an animal model. Given these results, manual bone biopsy methods should be encouraged after consideration for lesion composition, difficulty of access and the patient's overall condition.

Spinal Injections.

Spinal pain is a common complaint and cause of disability in the United States, affecting most individuals at some point in their lives. The complex anatomy of the spine leads to multiple potential and coexisting etiologies for pain, and the differentiation of these sources can present a diagnostic challenge. Image-guided spinal injections can provide both diagnostic information identifying pain location as well as prolonged therapeutic relief as an alternative to medical management. Anesthetic and corticosteroid medications can be administered within the epidural space through transforaminal or interlaminar approaches, blocking various sensory nerves, or directly within the facet joints. Proceduralists must be aware of associated patient considerations, techniques, and potential complications to perform the procedures safely. We discuss image-guided spinal injection techniques, based on best practices and our experiences.

Minding the Gap in Vertebroplasty: Vertebral Body Fracture Clefts and Cement Nonunion.

BACKGROUND: Vertebroplasty and kyphoplasty are leading treatments for patients with vertebral body compression fractures. Although cement augmentation has been shown to help relieve pain and instability from fractures containing a cleft, there is some controversy in the literature regarding the procedure's efficacy in these cases. Additionally, some of the literature blurs the distinction between clefts and cement patterns (including cement nonunion and cement fill pattern). Both clefts and cement patterns have been mentioned in the literature as risks for poorer outcomes following cement augmentation, which can result in complications such as cement migration. OBJECTIVES: This study aims to identify the prevalence of fracture clefts and cement nonunion, the relationship between them as well as to cement fill pattern, and their association with demographics and other variables related to technique and outcomes. STUDY DESIGN: Retrospective cohort study. SETTING: Interventional radiology department at a single site university hospital. METHODS: This retrospective cohort study assessed 295 vertebroplasties/kyphoplasties performed at the University of Colorado Hospital from 2008 to 2018. Vertebral fracture cleft and cement nonunion were the main variables of interest. Presence and characterization of a fracture cleft was determined on pre-procedural imaging, defined as an air or fluid filled cavity within the fractured vertebral body on magnetic resonance or computed tomography. Cement nonunion was evaluated on post-procedural imaging, defined as air or fluid surrounding the cement bolus on magnetic resonance or computed tomography or imaging evidence of cement migration. Cement fill pattern was assessed on procedural and/or post-procedural imaging. Pain improvement scores were based on a visual analog score immediately prior to the procedure and during clinical visits in the short-term follow-up period. Additional patient demographics, medical history, and procedure details were obtained from electronic medical chart review. RESULTS: Pre-procedural vertebral fracture clefts were demonstrated in 29.8% of our cases. Increasing age, secondary osteoporosis, and thoracolumbar junction location were associated with increased odds of clefts. There was no significant difference in pain improvement outcomes in patients following cement augmentation between clefted and non-clefted compression fractures. Clefts, especially large clefts, and cleft-only fill pattern were associated with increased odds of cement nonunion. Procedure techniques (vertebroplasty, curette, and balloon kyphoplasty) demonstrated similar proportion of cement nonunion and distribution of cement fill pattern. LIMITATIONS: Cement nonunion was observed in only 6.8% of cases. Due to this low proportion, statistical inference tends to have low power. Multiple levels were treated in nearly half of the study's patients undergoing a single vertebroplasty/kyphoplasty session; in these cases, each level was treated as independent rather than spatially correlated within the same study patient. CONCLUSIONS: Vertebral body fracture clefts are not uncommon and are related to (but distinct from) cement nonunion and cement fill patterns. Our study shows that, although patients with clefts will benefit from cement augmentation just as much as patients without a cleft, the performing provider should take note of cement fill and take extra steps to ensure optimal cement fill. These providers should also identify cement nonunion and associated complications (such as cement migration) on follow-up imaging.

Severity of heterotopic ossification in patients following surgery for hip fracture: a retrospective observational study.

BACKGROUND: Heterotopic ossification (HO) is a relatively common complication following hip surgery treated with open reduction and internal fixation, total arthroplasty or hemiarthroplasty. Development of HO after hip surgery is an important clinical issue as it can affect functional status. We aimed to determine whether there was association between severity of heterotopic ossification about the hip and the interval between the time of hip fracture and surgery. MATERIALS AND METHODS: Our retrospective study included 151 patients (age range 33-95 years) treated for hip fractures by hemiarthroplasty. Medical records were reviewed for time interval to surgery, laterality, surgical approach, and patient age. Patients who had any post-operative complications were excluded. Radiographs were semiquantitatively assessed for the degree of heterotopic ossification based on Brooker Classification (5-point scale). Statistical analysis was performed utilizing Chi-square, Kruskal-Wallis, and Score tests, and also a proportional odds model (significance level set at 0.05). RESULTS: Thirty eight patients had no heterotopic ossification, 43 had class 1, 55 had class 2, and 15 had class 3 or greater heterotopic ossification. The majority of patients (59.6%) had surgery within 2 days of acute injury. Severe heterotopic ossification (HO 3+) was associated with the longer interval between the time of acute hip fracture and surgery (median 6 days) vs. median 2 days in all other groups (HO classes 0-2) (p = 0.0015). The odds ratio and 95% CI for one level higher HO class was 1.296 (1.152, 1.459), which meant that the odds of having HO class one level higher increased by about 29.6% for every one-day increase in the days to surgery. No significant association was found for other variables. CONCLUSION: Class 3 or greater HO was associated with longer time interval between time of acute hip fracture and surgery compared to all other groups (HO class 0-2).

A Rare Incidence of Pigmented Villonodular Synovitis of the Ankle in an Adolescent.

Pigmented villonodular synovitis mostly affects the knee and other large joints such as the hip. Although the disease is most commonly found in adult patients aged 30 to 40 years, rare cases in children and the elderly have been reported. We present the case of an 11-year-old female who was found to have biopsy-proven pigmented villonodular synovitis in her subtalar joint in 2012. Five years after surgical excision, the patient has continued to be involved in competitive dancing and cheerleading without any pain in her ankle. Moreover, follow-up magnetic resonance imaging studies showed no evidence of recurrence. Our case report emphasizes that the disease should not be solely considered in the middle-age population but should be included in the differential diagnosis of the pediatric patient.

Low-dose, prospective triggered high-pitch spiral coronary computed tomography angiography: comparison with retrospective spiral technique.

RATIONALE AND OBJECTIVES: Cardiac computed tomographic angiography algorithms emphasize radiation reduction while maintaining diagnostic image quality (IQ). The aim of this study was to evaluate IQ and interreader variability using prospective electrocardiographically triggered high-pitch spiral cardiac computed tomographic angiography (FLASH-CT) compared to retrospective electrocardiographic gating (RETRO-CT) for coronary artery disease evaluation in a patient population including overweight and obese individuals. MATERIALS AND METHODS: Seventy patients (24 women; mean age, 60 years) matched for gender, age, body mass index (27.4 ± 5.5 kg/m(2)), and calcium score (184 ± 328) underwent cardiac computed tomographic angiography, 35 with FLASH-CT (Definition Flash) and 35 with RETRO-CT (Somatom Definition). Images were reconstructed using standard protocols and least motion phase for RETRO-CT acquisitions. Two independent, blinded readers evaluated the coronary arteries using an 18-segment model, grading IQ on a 5-point, Likert-type scale and coronary stenosis on a 5-point semiquantitative and binary scale. RESULTS: Effective radiation dose (1.50 vs 17.3 mSv, P < .0001) and mean heart rate (58 vs 62 beats/min, P < .05) were significantly lower for FLASH-CT compared to RETRO-CT. Seven hundred forty segments (> 1.5 mm) were evaluated. There was no significant difference between FLASH-CT and RETRO-CT scans in overall per-segment IQ (3.11 ± 0.75 vs 3.10 ± 0.82, P = .94). FLASH-CT had noninferior IQ relative to RETRO-CT (95% confidence interval, -0.25 to 0.26). There was no significant difference in interreader variability in diagnosis between FLASH-CT and RETRO-CT for all coronary segments (77.5% vs 78.2%, P = .83). CONCLUSIONS: FLASH-CT is an acceptable coronary computed tomographic angiographic method for reducing radiation dose without compromising IQ for a patient population including overweight and obese individuals.