Claire Park

MRI-guided focal laser ablation (FLA) is a promising minimally-invasive therapy method for men with localized prostate cancer. We previously developed an MR-compatible mechatronic system capable of transperineal needle delivery within an in-bore 3T MRI environment. This work presents an improved multi-fiducial structure for robust registration of the mechatronic system for MRI-guided FLA needle delivery. Real-time MRI-guided needle delivery was performed in a tissue-mimicking prostate phantom to virtual targets simulating focal ablation zones. With the implementation of the improved multi-fiducial structure, mechatronics-assisted MRI-guided needle delivery enables a 1.44 mm ablation radius, showing potential utility for accurate FLA to small prostate lesions.

Saliva has been a COVID-19 diagnostic specimen of interest due to its simple collection, scalability, and yield. Yet COVID-19 testing and estimates of the infectious period remain largely based on nasopharyngeal and nasal swabs. We sought to evaluate whether saliva testing captured prolonged presence of SARS-CoV-2 and potential infectiousness later in the disease course. We conducted an observational study of symptomatic COVID-19 patients at University Hospital in Newark, NJ. Paired saliva and nasal specimens from 96 patients were analyzed, including longitudinal analysis of paired observations from 28 of these patients who had multiple time-points. Saliva detected significantly more cases of COVID-19 beyond 5 days (86.1% [99/115] saliva vs 48.7% [56/115] nasal, p-value < 0.001), 9 days (79.4% [50/63] saliva vs 36.5% [23/63] nasal, p-value < 0.001) and 14 days (71.4% [20/28] saliva vs 32.1% [9/28] nasal, p-value = 0.010) of symptoms. Additionally, saliva yielded lower cycle thresholds across all time periods, indicative of higher viral loads in saliva. In the longitudinal analysis, a log-rank analysis indicated that the survival curve for saliva was significantly different from the curve for nasal swabs (p<0.001) with a median survival time for saliva of 18 days compared to 13 days for nasal swabs. We additionally performed saliva viral cultures among a similar COVID-19 patient cohort and noted patients with positive saliva viral cultures between 7 to 28 days of symptoms. Findings from this study suggest that SARS-CoV-2 RNA persists longer and in higher abundance in saliva compared to nasal swabs, with potential of prolonged propagating virus. Testing saliva may thus increase yield for detecting potentially infectious virus even beyond the first five days of symptomatic COVID-19.

Introduction. Non-invasive sample collection and viral sterilizing buffers have independently enabled workflows for more widespread COVID-19 testing by reverse-transcriptase polymerase chain reaction (RT-PCR). Gap statement. The combined use of sterilizing buffers across non-invasive sample types to optimize sensitive, accessible, and biosafe sampling methods has not been directly and systematically compared. Aim. We aimed to evaluate diagnostic yield across different non-invasive samples with standard viral transport media (VTM) versus a sterilizing buffer eNAT- (Copan diagnostics Murrieta, CA) in a point-of-care diagnostic assay system. Methods. We prospectively collected 84 sets of nasal swabs, oral swabs, and saliva, from 52 COVID-19 RT-PCR-confirmed patients, and nasopharyngeal (NP) swabs from 37 patients. Nasal swabs, oral swabs, and saliva were placed in either VTM or eNAT, prior to testing with the Xpert Xpress SARS-CoV-2 (Xpert). The sensitivity of each sampling strategy was compared using a composite positive standard. Results. Swab specimens collected in eNAT showed an overall superior sensitivity compared to swabs in VTM (70 % vs 57 %, P=0.0022). Direct saliva 90.5 %, (95 % CI: 82 %, 95 %), followed by NP swabs in VTM and saliva in eNAT, was significantly more sensitive than nasal swabs in VTM (50 %, PP=0.0012) and oral swabs in VTM (50 %, PPConclusion. Saliva and eNAT sterilizing buffer can enhance safe and sensitive detection of COVID-19 using point-of-care GeneXpert instruments.

Introduction: Competency assessment and quality assurance are significant aspects of point‐of‐care ultrasound (POCUS) training for residents and medical students. However, due to the COVID‐19 pandemic, alterations in programs have caused a need to develop new models of online assessments for students. While novel alterations in the curriculum have been made, clear learning outcomes and strategies must still teach the best practices. At the California University of Science and Medicine, School of Medicine (CUSM‐SOM), we aim to adapt training and assessment tools that include SonoSim LiveScan experiences. Sonosim, Inc. has developed a tool that students can use remotely to mimic the clinical applications traditionally done in person. This would allow students to familiarize themselves with normal and pathologic scans remotely and hone their diagnostic abilities without requiring in‐person faculty‐led sessions. There have already been multiple medical schools that have added SonoSim to supplement their curriculum and assess students’ competencies. This study aims to develop an online system of reliable competency‐based assessments for medical students in the teaching of POCUS. Methods: After completing each ultrasound module on SonoSim LiveScan alongside the schools’ corresponding system‐based courses, students will be assessed for achievement of competencies and learning outcomes. Students will take an online quiz and submit sonographic images that they obtained on their own time using provided standardized patients. The students will submit the images taken according to the guidelines mapped by the courses’ learning outcomes. Submissions will be through a secured online system. Quizzes will be graded with a predetermined grading system. Using a standardized rubric, three faculty members/instructors will assess scans for competency and quality. Results: Assessment will be completed in two steps. The first step will include an assessment of medical knowledge and concepts via an online quiz. The quiz will have still images and short video clips from SonoSim LiveScan to gauge the mastery of knowledge. The second step of the assessment will include a review of the ultrasound images obtained by the student. They will complete this part of the assessment on their own, asynchronously, and within a defined period of time. Then, three faculty members will score the images independently. To maintain the quality of the assessment, all instructors must agree that the required competencies have been achieved. All major discrepancies between the instructors regarding the results and assessment will be addressed according to the predetermined guidelines. Conclusion: This competency‐based assessment and training identifies students’ areas of weakness and makes review and remediation easy and straightforward. Clear objectives, teaching modalities, and assessments set the foundation for a successful ultrasound program. Competency‐based assessment as outlined above could be the best possible method to ensure students are involved and learning accurately during primarily remote learning times. By outlining a program that is easily implementable and accessible, ultrasound education will be made more available and widespread to medical students who would otherwise not be exposed.