A robust and inexpensive phantom for fluoroscopically guided lumbar puncture training

Electro-localization method using a muscle conductive phantom for needle position detection towards medical training

Simulation in healthcare can help train, improve, and evaluate medical personnel's skills. In the case of needle insertion/manipulation inside the muscle during an nEMG examination, a training simulator Requires estimating the position of the needle to output the electrical muscle activity in real time according to the training plan. External cameras can be used to estimate the needle location; however, different error sources can make its implementation difficult and new medical sensing technologies are needed. This study introduces and demonstrates the feasibility of a conductive phantom that serves as the medium for needle insertion and senses the 3D needle position based on a technique named electro-localization for the first time. The proposed conductive phantom is designed so that different voltage distributions are generated in the phantom using electrodes placed on its borders. The needle is inserted in the phantom, and the recorded voltages are mapped to spatial coordinates using a finite element method (FEM)-based computational model of the conductive phantom to estimate the 3D needle tip position. Experimental and simulation results of phantom voltage distributions agreed. In 2D mapping (no depth consideration), the needle position error was 1.7 mm, which was marginally reduced if only the central area of the phantom was used (1.5 mm). In 3D mapping, the error was 4 mm. This study showed the feasibility of using a conductive muscle phantom as a new embedded sensor that estimates needle position for medical training of nEMG without relying on external sensors.

The Development and Application of a Cost-Effective Cervical Spine Phantom for Use in Fluoroscopically Guided Lateral C1-C2 Spinal Puncture Training

BACKGROUND AND PURPOSE

Lateral C1-C2 spinal punctures are uncommon procedures performed by radiologists for access to CSF and contrast injection when a lumbar approach is contraindicated and an alternate method of access becomes necessary. There are limited opportunities to learn and practice the technique. We aimed to develop and assess the efficacy of a low-cost, reusable cervical spine phantom for training in fluoroscopically guided lateral C1-C2 spinal puncture.

MATERIALS AND METHODS

The phantom was constructed with a cervical spine model, an outer tube representing the thecal sac, an inner balloon representing the spinal cord, and polyalginate to replicate soft tissue. The total cost of materials was approximately US $70. Workshops were led by neuroradiology faculty experienced in the procedure using the model under fluoroscopy. Survey questions were assessed on a 5-point Likert scale. Participants were given pre- and postsurveys assessing comfort, confidence, and knowledge of steps.

RESULTS

Twenty-one trainees underwent training sessions. There was significant improvement in comfort level (Δ: 2.00, SD: 1.00, P value < .001); confidence (Δ: 1.52 points, SD: 0.87, P value < .001); and knowledge (Δ: 2.19, SD: 0.93, P value < .001). Eighty-one percent of participants found the model "very helpful" (5/5 on Likert scale), and all participants were "very likely" to recommend this workshop to others.

CONCLUSIONS

This cervical phantom model is affordable and replicable and demonstrates training utility to prepare residents for performing lateral C1-C2 spinal puncture. This is a rare procedure, so the use of a phantom model before patient encounters is invaluable to resident education and training.

Engineering functional and anthropomorphic models for surgical training in interventional radiology: A state-of-the-art review

Training medical students in surgical procedures and evaluating their performance are both necessary steps to ensure the safety and efficacy of surgeries. Traditionally, trainees practiced on live patients, cadavers or animals under the supervision of skilled physicians, but realistic anatomical phantom models have provided a low-cost alternative because of the advance of material technology that mimics multi-layer tissue structures. This setup provides safer and more efficient training. Many research prototypes of phantom models allow rapid in-house prototyping for specific geometries and tissue properties. The gel-based method and 3D printing-based method are two major methods for developing phantom prototypes. This study excluded virtual reality based technologies and focused on physical phantoms, total 189 works published between 2015 and 2020 on anatomical phantom prototypes made for interventional radiology were reviewed in terms of their functions and applications. The phantom prototypes were first categorized based on fabrication methods and then subcategorized based on the organ or body part they simulated; the paper is organized accordingly. Engineering specifications and applications were analyzed and summarized for each study. Finally, current challenges in the development of phantom models and directions for future work were discussed.

Cadaveric Simulation Training Improves Residents' Knowledge and Confidence in Performing Fluoroscopic Guided Joint Injections

RATIONALE AND OBJECTIVE

Simulation training has been strongly encouraged to enhance radiology trainees' procedural competency. We aimed to assess whether a cadaveric simulation training session was effective in improving radiology residents' subjective technical ability, knowledge and confidence in performing fluoroscopic-guided joint injections.

METHODS

As part of the residency program's procedural training curriculum, first year radiology resident participated in a cadaveric, musculoskeletal injection training session including a didactic lecture followed by a practical hands-on component. Trainees performed fluoroscopic guided hip and shoulder injections on fresh cadavers, supervised by two fellowship-trained musculoskeletal radiologists. Trainees' knowledge on indications, contraindications, preprocedural care, complications, and technical ability in performing the procedures, as well as their rating of overall session experience were evaluated with pre- and post-session questionnaires (5 point Likert-scale). The mean residents' scores for pre- and post-session questionnaire items were calculated and compared using paired t-test. The magnitude of difference between mean pre- and post-session scores was compared between the items using analysis of variance.

RESULTS

Results Over a 5-year period, 27 trainees participated in the joint injection simulation session. The mean pre- and post-session scores were significantly higher in the post session questionnaire for all five items pertaining to knowledge of indications, contraindications, preprocedural care, complications, and technical ability (all p < 0.0001). The magnitude of improvement was not different between the items (p = 0.45). Most of the participants rated the training facilities, contents, hands-on experience, teaching quality, and session organization as very good or excellent.

CONCLUSIONS

Cadaveric joint injection simulation training significantly improved trainees' subjective knowledge, confidence, and technical ability in performing joint injections.

State-of-the-art of lumbar puncture and its place in the journey of patients with Alzheimer's disease

Recent advances in developing disease‐modifying therapies (DMT) for Alzheimer's disease (AD), and the recognition that AD pathophysiology emerges decades before clinical symptoms, necessitate a paradigm shift of health‐care systems toward biomarker‐guided early detection, diagnosis, and therapeutic decision‐making. Appropriate incorporation of cerebrospinal fluid biomarker analysis in clinical practice is an essential step toward system readiness for accommodating the demand of AD diagnosis and proper use of DMTs—once they become available. However, the use of lumbar puncture (LP) in individuals with suspected neurodegenerative diseases such as AD is inconsistent, and the perception of its utility and safety differs considerably among medical specialties as well as among regions and countries. This review describes the state‐of‐the‐art evidence concerning the safety profile of LP in older adults, discusses the risk factors for LP‐associated adverse events, and provides recommendations and an outlook for optimized use and global implementation of LP in individuals with suspected AD.

Interventional pain training using phantom model during COVID-19 pandemic

Background

Fluoroscopic‐guided lumbar procedures have increased in daily pain practice because the lumbar spine is one of the most common sources of pain. Interventional pain fellows must develop a minimum number of skills during their training in order to achieve the competences without neglecting radiological safety. However, medical training in fluoroscopic‐guided interventions is being affected by the current coronavirus disease 2019 (COVID‐19) situation.

Methods

The objective of this study was to evaluate the use of a phantom model for lumbar injection as a training strategy during the COVID‐19 pandemic in fellows of interventional pain. The study was divided into theoretical and practical modules. The hands‐on practice was performed in a lumbar model phantom where fellows were evaluated in four fluoroscopically guided approaches: intra‐articular facet block (IAFB), medial branch block (MBB), transforaminal block (TFB), and interlaminar block (ILB) divided in 5 sessions. The aim was to make as many punctures as possible in every session. We measured total procedural performance (TPP), total needle hand time (TNH), and total radiation dose generated by the fluoroscopic machine (TRD) during each procedure. Additionally, a survey was applied to evaluate confidence and satisfaction before and after training.

Results

A total of 320 lumbar punctures were completed. The results were statistically significant in all approaches attempted (p < 0.01). The fellow’s survey for satisfaction and confidence demonstrated a significant difference between pre and post‐test (p < 0.01).

Conclusions

The results of this study highlight the importance of adaptations and adoption of new educational models. The use of the phantom model for simulation could be a strategy for other emerging situations, like the COVID‐19 pandemic. Including this practice in the interventional pain programs could lead to better results for the patient and operator radiology safety.

Lumbar Puncture: Creation and Resident Acceptance of a Low-Cost, Durable, Reusable Fluoroscopic Phantom with a Fluid-Filled Spinal Canal for Training at an Academic Program

Simulation-based medical training provides learners a method to develop technical skills without exposing patients to harm. Although fluoroscopic phantoms are already adopted in some areas of radiology, this has historically not been for lumbar puncture. Commercially available phantoms are expensive. We report a cost-effective, accessible solution by creation of an inexpensive phantom for resident training to perform fluoroscopically guided lumbar puncture, as well as instructions on how to make a phantom for residency education. An anthropomorphic ballistics-gel phantom that contains a plastic lumbar vertebral column and simulated CSF space was created. Radiology residents with minimum or no experience with fluoroscopically guided lumbar punctures were given a brief education and practiced fluoroscopically guided lumbar punctures on the phantom. A survey from the residents was then done. The phantom was qualitatively quite durable and deemed adequate for educational purposes. All the residents surveyed expressed the desire to have this phantom available and it increased comfort, knowledge, and perceived likelihood of success. Few articles have been published that focused on low-cost phantom creation for fluoroscopic-procedure training. This study supports the benefits of using phantoms for fluoroscopic training as well as step-by-step instructions for creation of this phantom. The residents responded positively and felt more confident in their fluoroscopically guided techniques. The ability to make a long-term training device for resident education would be inexpensive and relatively easy to implement in academic programs.

A prototype assembled 3D-printed phantom of the glenohumeral joint for fluoroscopic-guided shoulder arthrography

PURPOSE

To describe the methodology of constructing a three-dimensional (3D) printed model of the glenohumeral joint, to serve as an interventional phantom for fluoroscopy-guided shoulder arthrography training.

MATERIALS AND METHODS

The osseous structures, intra-articular space and skin surface of the shoulder were digitally extracted as separate 3D meshes from a normal CT arthrogram of the shoulder, using commercially available software. The osseous structures were 3D-printed in gypsum, a fluoroscopically radiopaque mineral, using binder jet technology. The joint capsule was 3D printed with rubber-like TangoPlus material, using PolyJet technology. The capsule was secured to the humeral head and glenoid to create a sealed intra-articular space. A polyamide mold of the skin was printed using selective laser sintering. The joint was stabilized inside the mold, and the surrounding soft tissues were cast in silicone of varying densities. Fluoroscopically-guided shoulder arthrography was performed using anterior, posterior, and rotator interval approaches. CT arthrographic imaging of the phantom was also performed.

RESULTS

A life-size phantom of the glenohumeral joint was constructed. The radiopaque osseous structures replicated in-vivo osseous corticomedullary differentiation, with dense cortical bone and less dense medullary cancellous bone. The glenoid labrum was successfully integrated into the printed capsule, and visualized on CT arthrography. The phantom was repeatedly used to perform shoulder arthrography using all three conventional approaches, and simulated the in vivo challenges of needle guidance.

CONCLUSIONS

3D printing of a complex capsule, such as the glenohumeral joint, is possible with this technique. Such a model can serve as a valuable training tool.

Non-dominant hand quicker to insert peripheral venous catheters under echographic guidance: A randomised trial

BACKGROUND

Ultrasound guidance for venous catheter placement requires the use of both hands. An accurate and stable ultrasound image is fundamental for obtaining good quality images, consequently permitting accurate needle placement. We hypothesized that the dominant hand could be used to perform echography, leaving the non-dominant hand available for peripheral venous catheter (PVC) insertion.

METHODS

Prospective, open-label, randomized, crossover study. Group 1 inserted the PVC with the dominant hand, and held the probe with the non-dominant hand in a first series of 20 insertions, and vice versa in a second series of 20 insertions performed 11days later. Group 2 punctured with the non-dominant hand in Series 1 and vice versa in series 2. The study population comprised female student nurses (aged 20-30years) who had learned neither ultrasound techniques nor catheter insertion. The primary endpoint was time to successful puncture. We recorded age, sex, video game use, and the laterality of hands, feet and eyes.

RESULTS

One left-handed and nine right-handed nurses were randomized to each group. Puncture by the non-dominant hand was significantly quicker in both series (P<0.001). There was no difference between groups for time to successful puncture with the dominant hand; however a significant difference was found for the non-dominant hand (P<0.01). According to multivariate analysis, the time to successful puncture was significantly lower when the non-dominant hand was used to puncture (adjusted difference 5.6s, P<0.0001).

CONCLUSION

Using the dominant hand to hold the ultrasound probe and the non-dominant hand to puncture and insert the catheter achieves successful insertion in a significantly shorter time.

Simulation-based educational curriculum for fluoroscopically guided lumbar puncture improves operator confidence and reduces patient dose

RATIONALE AND OBJECTIVES

Fluoroscopically guided lumbar puncture (FGLP) is a commonly performed procedure with increased success rates relative to bedside technique. However, FGLP also exposes both patient and staff to ionizing radiation. The purpose of this study was to determine if the use of a simulation-based FGLP training program using an original, inexpensive lumbar spine phantom could improve operator confidence and efficiency, while also reducing patient dose.

MATERIALS AND METHODS

A didactic and simulation-based FGLP curriculum was designed, including a 1-hour lecture and hands-on training with a lumbar spine phantom prototype developed at our institution. Six incoming post-graduate year 2 (PGY-2) radiology residents completed a short survey before taking the course, and each resident practiced 20 simulated FGLPs using the phantom before their first clinical procedure. Data from the 114 lumbar punctures (LPs) performed by the six trained residents (prospective cohort) were compared to data from 514 LPs performed by 17 residents who did not receive simulation-based training (retrospective cohort). Fluoroscopy time (FT), FGLP success rate, and indication were compared.

RESULTS

There was a statistically significant reduction in average FT for the 114 procedures performed by the prospective study cohort compared to the 514 procedures performed by the retrospective cohort. This held true for all procedures in aggregate, LPs for myelography, and all procedures performed for a diagnostic indication. Aggregate FT for the prospective group (0.87 ± 0.68 minutes) was significantly lower compared to the retrospective group (1.09 ± 0.65 minutes) and resulted in a 25% reduction in average FT (P = .002). There was no statistically significant difference in the number of failed FGLPs between the two groups.

CONCLUSIONS

Our simulation-based FGLP curriculum resulted in improved operator confidence and reduced FT. These changes suggest that resident procedure efficiency was improved, whereas patient dose was reduced. The FGLP training program was implemented by radiology residents and required a minimal investment of time and resources. The LP spine phantom used during training was inexpensive, durable, and effective. In addition, the phantom is compatible with multiple modalities including fluoroscopy, computed tomography, and ultrasound and could be easily adapted to other applications such as facet injections or joint arthrograms.