Benign bony tumors of the paranasal sinuses, orbit, and skull base.

Benign bony tumors of the skull base and paranasal sinuses are uncommon entities, with an overall higher incidence in males. Benign bony tumors may lead to local expansion with resultant mass effect of potentially critical structures. Some benign bony tumors may undergo malignant transformation. This article reviews the presentation and management of benign bone tumors of the skull base and paranasal sinuses with special consideration to involvement of the adjacent orbit, intracranial and critical neurovascular structures. This review covers tumor incidence, location, gross and histologic appearance as well as radiographic findings, treatment, and recurrence rates. Tumors discussed in this article include osteochondromas, osteomas, osteoid osteomas, aneurysmal bone cysts, fibrous dysplasia, giant cell tumors, cemento-ossifying fibroma, ameloblastic fibro-odontoma, ecchordosis physaliphora, chondromyxoid fibroma, primary chronic osteomyelitis, primary chronic osteomyelitis, osteochondromyxoma, and dense bone islands.

I.C.A.R.U.S. in Flight: A Radiology Simulator Teaches Imaging Appropriateness, Anatomy, and Image Interpretation Skills.

RATIONALE AND OBJECTIVES: The Interactive Clinical Anatomy and Radiology Utilization Simulator (ICARUS) was created in 2012 as a novel simulation program with 25 peer reviewed electronic modules combining simulated patient encounters, American College of Radiology appropriateness criteria, radiologic anatomy, and basic imaging interpretation and patient safety topics. ICARUS integrates a gaming approach to improve student engagement. MATERIALS AND METHODS: ICARUS modules have been used in the undergraduate medical curriculum at the lead author's institution since its pilot in 2012. Since completion of the full complement of 25 modules, modules have been used in the radiology clerkship (2012- 2015), in the integrated longitudinal curriculum (2015-present), and in various radiology electives (2015-present), including the inaugural virtual radiology electives at all authors' institutions (July 2020-present). Student evaluations were formally solicited in 2014 and again in 2020. RESULTS: During the introductory radiology clerkship in 2014, 107 students were enrolled. Students were assigned 4 ICARUS modules. During the 2-week virtual elective from July-October 2020, 26 students were enrolled. Students were assigned all 25 modules. The majority of survey respondents "agreed" or "strongly agreed" that the modules were interactive, enjoyable, and self-directed, fostered critical thinking, provided practical value, met goals and objectives of the course, and seemed practical to their future practice. CONCLUSION: ICARUS integrates key educational concepts in radiology with high fidelity simulation of clinical decision support software and PACS simulation image display to create a highly engaging learning environment that most accurately reflects future clinical experiences.

Virtual Journal Club Beyond the Pandemic: An Enduring and Fluid Educational Forum.

OBJECTIVE: Since its inception, journal club has been a cornerstone to the life-long process of medical education. The virtual journal club (VJC), initiated as a robust solution to many educational challenges encountered during COVID-19 pandemic-related distance learning, provides an enduring and fluid forum for multilevel teaching and learning. MATERIALS AND METHODS: In this manuscript we share our institutions' reasoning and methods to implement a VJC for multi-level learners. A standardized format applicable to all VJC sessions was adopted to ensure reproducibility from presenter to presenter. Sessions were held via video conference platforms. Pedagogy regularly emphasized in undergraduate medical education was adopted. Informal assessment of each session's strengths and areas for improvement was performed. RESULTS: A total of 30 sessions were held prior to manuscript submission, including discussion of 36 refereed journal articles from March 26, 2020, to April 20, 2021. The virtual journal club was very well received by all participants. The medical students and residents found the information current and engaging. The fellows stated that the journal club strengthened their knowledge base and enhanced communication and teaching skills. The attendings learned from its encouraged frank discussion of differing practice patterns. The format of these sessions offers an ideal setting to teach medical students and residents how to evaluate and employ evidence-based medicine and meets multiple LCME and ACGME requirements. CONCLUSIONS: This VJC forum allows for development of essential nonclinical skills including lifelong active learning and analysis, peer collaboration, and technology adaptation and usage.

A specific biomarker for amyotrophic lateral sclerosis: Quantitative susceptibility mapping.

OBJECTIVE: Accurate and timely diagnosis of amyotrophic lateral sclerosis (ALS) is a diagnostic challenge given the lack of specific diagnostic and imaging biomarkers as well as the significant clinic overlap with mimic syndromes. We hypothesize that MR quantitative susceptibility mapping (QSM) can help differentiate ALS from mimic diagnoses. METHODS: In a blinded retrospective study of MRIs with QSM from 2015 to 2018, we compared motor cortex susceptibility along the hand and face homunculi in ALS patients and patients with similar clinical presentations. Inclusion required a confirmed ALS or a mimic diagnosis. Comparative groups included age-matched patients with MRIs performed for non-motor neuron symptoms that were reported as normal or demonstrated leukoaraiosis. Quantitative susceptibility values were compared with ANOVA and Tukey-Kramer (post-hoc). ROC analysis and Youden's index were used to identify optimal cutoff values. RESULTS: Fifty ALS, 35 mimic, and 70 non-motor neuron symptom patients (35 normal, 35 leukoaraiosis) were included. Hand and face homunculus mean susceptibility values were significantly higher in the ALS group compared to the mimic (p=0.001, p=0.004), leukoaraiosis (p<0.001, p=0.003), and normal (p<0.001, p<0.001) groups. ROC curve analysis comparing ALS to mimics resulted in an area under the curve of 0.71 and 0.67 for the hand and face homunculus measurements, respectively. In differentiating ALS from mimics, Youden's index showed 100% specificity and 36% sensitivity for hand homunculus measurements. CONCLUSIONS: QSM has diagnostic potential in the assessment of suspected ALS patients, demonstrating very high specificity in differentiating ALS from mimic diagnoses.

Medical student education in the time of COVID-19: A virtual solution to the introductory radiology elective.

RATIONALE AND OBJECTIVES: During the COVID-19 pandemic, medical educators and students are facing unprecedented challenges while navigating the new virtual landscape that social-distancing policies mandate. In response to these challenges, a new virtual introduction to radiology elective was established with unique online resources and curriculum. MATERIALS AND METHODS: A previously in-person 2-week introductory radiology elective was converted into a completely virtual experience using an internally developed, open-source, peer-reviewed, web-based teaching modules combined with virtual lectures, interdisciplinary conferences, and readout sessions of de-identified cases loaded to a DICOM viewer. Students from the first four months of course enrollment completed a multiple choice pre- and post-course knowledge assessments and a 5-point Likert Scale survey as part of their educational experience. RESULTS: In total, 26 4th-year medical students participated over 4 separate 2-week sessions from July to October of 2020. This included 12 students from the home intuition and 14 visiting students. On average, students scored 62.2% on the 55-question pre-test and 89.0% on the same test upon completion of the course, a statistically significant increase (p < 0.001). All 26 students felt engaged throughout the course. All 26 agreed (23 "strongly agreed") that they were more comfortable looking at imaging studies following the course. All 26 also agreed (21 "strongly agreed") that the course helped them prepare for their future clinical rotations and careers. CONCLUSION: Initial pilot program using unique web-based resources and student encounters during a two-week virtual introductory radiology elective proved to be a positive educational experience for the first 26 students enrolled.

Concomitant calciphylaxis and COVID-19 associated thrombotic retiform purpura.

While initial reports regarding coronavirus disease 2019 (COVID-19) focused on its pulmonary manifestations, more recent literature describes multisystem abnormalities related to its associated microvascular angiopathy. Calciphylaxis is a rare systemic condition characterized by tissue necrosis in the setting of systemic microvascular calcifications. Both COVID-19 and calciphylaxis are procoagulant diagnoses associated with vascular-mediated cutaneous findings. To our knowledge, this is the first report to document the coexistence of COVID-19 associated retiform thrombotic purpura and calciphylaxis in a single patient, to link the pathologic etiologies of the two entities, and to describe the concomitant diagnoses' associated radiologic findings.

Imaging of Temporal Bone Trauma: A Clinicoradiologic Perspective.

Imaging plays an important role in the evaluation of temporal bone trauma. Certain imaging findings can significantly change patient management or change surgical approach. Precise knowledge of clinical or surgical management can guide the review of imaging to detect these key findings. This article reviews the clinical and imaging findings as well as management of complications from temporal bone trauma, including hearing loss, vertigo, perilymphatic fistula, cerebrospinal fluid leak, facial nerve injury and vascular injury.

Semi-automated Quantification of Lung Density on Chest CT Used as a Predictive Biomarker of Pulmonary Venous Hypertension.

RATIONALE AND OBJECTIVES: We sought to determine if lung densities derived from computed tomography scans could be used to identify patients with pulmonary venous hypertension (Group II pulmonary hypertension [PH]), and to compare the performance of this metric with previously described metrics. MATERIALS AND METHODS: Patients were retrospectively included from a single-center cohort of patients with aortic stenosis being evaluated for transcatheter aortic valve replacement from April 2009 to July 2014. Fifty-four patients met inclusion criteria. Thirty-three had PH (pulmonary arterial pressure [PAP] ≥25 mmHg). Thirty-two had Group II PH (pulmonary capillary wedge pressure [PCWP] ≥15 mmHg). Mean lung density (mLD) was measured from chest computed tomography scans using semi-automated techniques. Aortic diameter (mAo) and main pulmonary artery diameter (mPA) were measured manually. These metrics were correlated with PAP and PCWP values. RESULTS: mLD was significantly correlated with PCWP (R = 0.45, P = .0006) and significantly higher in patients with elevated PCWP (P = .006). mPA was weakly correlated with PCWP (R = 0.28, P = .04), but not significantly different in patients with elevated PCWP. mPA/mAo was not significantly correlated with PCWP, nor was it significantly different in patients with elevated PCWP. mLD, mPA, and mPA/mAo were all significantly correlated with PAP and were significantly higher in patients with PH. CONCLUSIONS: Of all metrics, only mLD was significantly correlated with PCWP and served to differentiate patients with elevated and normal PCWP. As such, mLD may contribute to a noninvasive biomarker of pulmonary venous hypertension.

MRI safety: a report of current practice and advancements in patient preparation and screening.

MRI offers detailed diagnostic images without ionizing radiation; however, there are considerable safety concerns associated with high electromagnetic field strength. With increasing use of high and ultra high (7T) magnetic field strength, adequate patient preparation and screening for ferrous material is increasingly important. We review current safety standards for patient screening and preparation and how they are implemented at our institution. In addition, we describe a novel supplemental screening technique wherein the lights are dimmed in response to detected ferrous metal at the threshold of Zone IV.

Adverse reactions to intravenous contrast media: an unexpected discrepancy between inpatient and outpatient cohorts.

Adverse reaction rates to computed tomography (CT) and magnetic resonance imaging (MRI) contrast agents are well published. However, there is no literature regarding systems-based changes to improve contrast reaction management. As part of ongoing quality improvement monitoring at our institution, contrast reaction events were reviewed. Contrast reactions for CT and MRI were captured at lower rates for the inpatient setting compared to outpatient by an order of a magnitude. The documented inpatient events were more likely to be severe in nature. Given this discrepancy, focus is being placed upon identifying potential barriers to capturing and appropriately managing inpatient contrast reactions.

An allele of sequoia dominantly enhances a trio mutant phenotype to influence Drosophila larval behavior.

The transition of Drosophila third instar larvae from feeding, photo-phobic foragers to non-feeding, photo-neutral wanderers is a classic behavioral switch that precedes pupariation. The neuronal network responsible for this behavior has recently begun to be defined. Previous genetic analyses have identified signaling components for food and light sensory inputs and neuropeptide hormonal outputs as being critical for the forager to wanderer transition. Trio is a Rho-Guanine Nucleotide Exchange Factor integrated into a variety of signaling networks including those governing axon pathfinding in early development. Sequoia is a pan-neuronally expressed zinc-finger transcription factor that governs dendrite and axon outgrowth. Using pre-pupal lethality as an endpoint, we have screened for dominant second-site enhancers of a weakly lethal trio mutant background. In these screens, an allele of sequoia has been identified. While these mutants have no obvious disruption of embryonic central nervous system architecture and survive to third instar larvae similar to controls, they retain forager behavior and thus fail to pupariate at high frequency.

Infliximab or cyclosporine for acute severe ulcerative colitis: a retrospective analysis.

BACKGROUND AND AIM: Medical treatment of steroid-refractory ulcerative colitis (UC) is limited to either cyclosporine or infliximab. Studies comparing cyclosporine with either placebo or intravenous methylprednisone showed promise for cyclosporine, but associated it with significant toxicity. There is conflicting, but increasingly positive evidence for using infliximab. There are no studies directly comparing these two treatments. Our aim was to compare the outcomes of patients with steroid-refractory UC treated with either intravenous cyclosporine or infliximab. METHODS: We carried out a retrospective review of inpatients with steroid-refractory UC, treated with either intravenous cyclosporine or infliximab, at Waitemata District Health Board, between January 2001 and February 2010. The primary end-points were time to colectomy, and colectomy rates at 3 and 12 months. Secondary end-points were time to discharge from initiation of treatment, steroid dependence at 12 months, and reported adverse events. RESULTS: The total study population was 38, with 19 in the infliximab group. Follow up to 12 months was complete in all patients. At 3 months, the colectomy rate was 63% for cyclosporine, compared to 21% (P = 0.0094). By 12 months the rate was 68% and 37% for cyclosporine and infliximab, respectively (P = 0.06). Patients in the cyclosporine group required an additional 5 days in hospital (P = 0.0086). Steroid dependence at 12 months was 50% for cyclosporine versus 25% for infliximab (P = 0.36). Cyclosporine caused more adverse events (P = 0.17). CONCLUSIONS: Infliximab improved clinical outcomes compared to the previous use of intravenous cyclosporine in patients admitted with steroid-refractory acute severe UC.

Selective holographic detection of glucose using tertiary amines.

Introducing tertiary amine monomers into holographic sensors containing phenylboronic acids gives greatly improved selectivity for glucose.

Crosslinking of phenylboronic acid receptors as a means of glucose selective holographic detection.

A holographic sensor for the detection of glucose has been developed that is based on a hydrogel film containing phenylboronic acid receptors. Changes to the replay wavelength of the hologram were used to characterise the swelling and de-swelling behaviour of the hydrogel matrix upon receptor-ligand binding. The effect of introducing a fixed positive charge into the polymer matrix by modification of the hydrogel with a quaternary amine group (3-acrylamidopropyl)trimethylammonium chloride (ATMA), was investigated for a range of sugars and the alpha-hydroxy acid, lactate, at physiological pH. The quaternary amine-modified hydrogel matrix was found to contract in the presence of glucose, whereas, it was minimally responsive to other saccharides. The selectivity of the sensor for glucose compared to lactate was also significantly improved compared to the unmodified film. A crosslinking mechanism is proposed to explain the enhanced selectivity to glucose.

A green fluorescent chemosensor for amino acids provides a versatile high-throughput screening (HTS) assay for proteases.

The water soluble fluorescein-based ligand 1 forms a non-fluorescent complex with Cu(2+). This complex serves as a fluorescent sensor for amino acids in the 10(-3) M concentration range. Since the signal response is very fast, the sensor can be used to detect the hydrolytic activity of various proteases (trypsin, chymotrypsin, subtilisin) on bovine serum albumin as a whole protein substrate, and more generally to follow reactions releasing or removing free amino acids, in real time.