Validation of the quality of ultrasound imaging and competence (QUICk) score as an objective assessment tool for the FAST examination.

BACKGROUND: The Focused Assessment with Sonography for Trauma (FAST) examination has become a valuable tool in trauma resuscitation. Despite the widespread use of FAST training among traumatologists, no evidence-based guidelines exist to support optimal training requirements or to provide quantitative objective assessments of imaging capabilities. Both Task-Specific Checklist (TSC) and Global Rating Scale (GRS) have been validated as objective skill assessment tools; we developed both types of scoring checklist and assessed them for construct validity with the FAST examination. METHODS: Two scoring checklists, collectively termed the Quality of Ultrasound Imaging and Competence (QUICk) Score, were developed and subjected to a modified Delphi consensus process. Two cohorts of 12 novice and 12 expert sonographers performed the FAST examination and were evaluated by two experts according to the QUICk model. Total scores as well as anatomic subsets were compared via comparison of means, and logistic regression modeling was used to determine sensitivity and specificity. RESULTS: Experts achieved significantly higher total scores than novices on both scoring systems (17.2 vs. 11.1 of 24, p < 0.01 TSC, 29.8 vs. 18.4 of 40, p < 0.01 GRS). Sensitivity (85.7% TSC, 92.9% GRS) and specificity (75.0% TSC, 91.7% GRS) as well as area under the receiver operating characteristic curve (89.9% TSC, 97.6% GRS) were consistent with a highly discriminant tool. CONCLUSION: The QUICk Score is the first validated objective tool for assessment of the quality of FAST examination imaging. Use of this tool may be instrumental in developing an evidence-based minimum-performance standard and for assessing quality-improvement modifications in FAST examination training.

The effect of blocked versus random task practice schedules on the acquisition and retention of surgical skills.

BACKGROUND: When learning multiple tasks, blocked or random training schedules may be used. We assessed the effects of blocked and random schedules on the acquisition and retention of laparoscopic skills. METHODS: Thirty-six laparoscopic novices were randomized to practice laparoscopic tasks using blocked, random, or no additional training. Participants performed immediate post-tests, followed by retention tests 6 weeks later. Outcomes included previously validated Fundamentals of Laparoscopic Surgery (FLS) and hand-motion efficiency scores. RESULTS: Both blocked and random groups had significantly higher FLS and hand-motion efficiency scores over baseline on post-tests for each task (P < .05) and higher overall FLS scores than controls on retention tests (P < .01). No difference was seen between the blocked and random groups in the amount of skill acquired or skill retained. CONCLUSIONS: Both blocked and random training schedules can be considered as valid training options to allow programs and learners to tailor training to their individual needs.

Design and Validation of 3D Printed Complex Bone Models with Internal Anatomic Fidelity for Surgical Training and Rehearsal.

Physical models of complex bony structures can be used for surgical skills training. Current models focus on surface rendering but suffer from a lack of internal accuracy due to limitations in the manufacturing process. We describe a technique for generating internally accurate rapid-prototyped anatomical models with solid and hollow structures from clinical and microCT data using a 3D printer. In a face validation experiment, otolaryngology residents drilled a cadaveric bone and its corresponding printed model. The printed bone models were deemed highly realistic representations across all measured parameters and the educational value of the models was strongly appreciated.

Construct validity of individual and summary performance metrics associated with a computer-based laparoscopic simulator.

BACKGROUND: Computer-based surgical simulators capture a multitude of metrics based on different aspects of performance, such as speed, accuracy, and movement efficiency. However, without rigorous assessment, it may be unclear whether all, some, or none of these metrics actually reflect technical skill, which can compromise educational efforts on these simulators. We assessed the construct validity of individual performance metrics on the LapVR simulator (Immersion Medical, San Jose, CA, USA) and used these data to create task-specific summary metrics. METHODS: Medical students with no prior laparoscopic experience (novices, N = 12), junior surgical residents with some laparoscopic experience (intermediates, N = 12), and experienced surgeons (experts, N = 11) all completed three repetitions of four LapVR simulator tasks. The tasks included three basic skills (peg transfer, cutting, clipping) and one procedural skill (adhesiolysis). RESULTS: We selected 36 individual metrics on the four tasks that assessed six different aspects of performance, including speed, motion path length, respect for tissue, accuracy, task-specific errors, and successful task completion. Four of seven individual metrics assessed for peg transfer, six of ten metrics for cutting, four of nine metrics for clipping, and three of ten metrics for adhesiolysis discriminated between experience levels. Time and motion path length were significant on all four tasks. We used the validated individual metrics to create summary equations for each task, which successfully distinguished between the different experience levels. CONCLUSION: Educators should maintain some skepticism when reviewing the plethora of metrics captured by computer-based simulators, as some but not all are valid. We showed the construct validity of a limited number of individual metrics and developed summary metrics for the LapVR. The summary metrics provide a succinct way of assessing skill with a single metric for each task, but require further validation.

Generation of a 3D printed temporal bone model with internal fidelity and validation of the mechanical construct.

OBJECTIVE: To generate a rapid-prototyped temporal bone model from computed tomography (CT) data with a specific focus on internal anatomic fidelity. STUDY DESIGN: Research ethics board-approved prospective cohort study. SETTING: Current iterations of a rapid-prototyped temporal bone model are complicated by absent void spaces and inconsistent bone density due to limited infiltrant exposure. The creation of a high-fidelity model allows surgical trainees to practice in a standardized and reproducible training environment. This learning paradigm will significantly augment resident understanding of surgical approaches and techniques to prevent adverse outcomes. SUBJECTS AND METHODS: We describe a technique for generating internally accurate rapid-prototyped anatomical models with solid and hollow structures, including void spaces. The novel slicing algorithm digitally deconstructs a model into segments and permits removal of extraneous print material and allows infiltrant penetration of the entire bone structure. Precise reassembly is facilitated by digitally generated fiducials. Infiltrant of choice was determined by expert assessment and subjected to objective mechanical property assessment with comparison to cadaveric sheep bone. RESULTS: The printed bone models are highly realistic. Void space representation was excellent with 88% concordance between cadaveric bone and the resultant rapid-prototyped temporal bone model. Ultimately, cyanoacrylate with hydroquinone was determined to be the most appropriate infiltrant for both cortical and trabecular simulation. The mechanical properties of all tested infiltrants were similar to real bone. CONCLUSION: This model serves as an excellent replica of a human temporal bone for training and preoperative surgical rehearsal and can be dissected in a true-to-life fashion.