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AR Projections for Eye-gaze Evaluation in Phantoms

AR Projections for Eye-gaze Evaluation in Phantoms

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07161024
Enrollment
8
Registered
2025-09-08
Start date
2024-10-14
Completion date
2025-02-05
Last updated
2026-04-20

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Kidney Stones

Keywords

Kidney Stones, Augmented Reality, Gaze Guidance

Brief summary

This project aims to develop an augmented reality (AR) tool to enhance skill acquisition for endoscopic kidney stone surgery. Of the 100,000 patients who undergo an endoscopic kidney stone treatment annually in the United States, 25% will require a repeat stone surgery within 20 months of their index surgery. The repeat stone surgery rate is almost completely driven by postoperative residual stone fragments, which lead to ureteral obstruction, causing pain, urinary tract infection, and kidney injury. One significant factor that contributes to residual stone fragments is limited visualization of the entire collecting system - a skill directly associated with surgeon experience. This leads to novice surgeons having a much higher recurrence rate than experienced ones. As the incidence of kidney stone disease continues to increase (prevalence of 10%, incidence of 1116 per 100,000), improved endoscopic surgical training is required to improve outcomes of stone surgeries and minimize complications by improving stone-free rate. Currently, skill assessment during endoscopic stone surgery is limited. There are no objective metrics for endoscopic surgery to assess skill. The only feedback trainees get is in the form of verbal communication from expert surgeons, usually after the conclusion of surgery. Thus, most feedback is synoptic and limited in facilitating skill acquisition. Operative time and patient safety concerns restrict the amount of active, real-time feedback given during a case for skill acquisition. Endoscopic kidney stone surgery is uniquely challenging given the small depth and field of view of current endoscopes, which complicate the complete visualization of the entire collecting system. Navigation of the collecting system relies on mentally mapping preoperative imaging to the endoscopic surgical field. Success in mapping relies on hand-eye coordination, memory, and spatial reasoning, which are gained through practice. Thus, there is a need for tools that facilitate endoscopic surgical skill acquisition. The overarching hypothesis for this research is that surgical skill acquisition and outcomes for endoscopic kidney stone surgery can be improved by analyzing eye gaze data and using expert gaze to guide surgical trainees intraoperatively. Eye gaze guidance has been shown to lead to better skill acquisition in virtual reality surgical tasks compared with motion guidance alone. The proposed system would provide real-time education for trainees during endoscopic stone surgery, such as through head-mounted displays (i.e., the Microsoft HoloLens 2). The investigators have previously demonstrated eye gaze sharing in phantoms. By implementing this system in the operating room (OR), the investigators would be able to instill durable skill acquisition in trainees. The investigators will also implement the NASA-task load index for the trainees to gauge the usability of the system.

Detailed description

Specifically for this study, the investigators are asking each participant, all surgical trainees, to explore four phantom kidneys with stones added and count the number of stones. For each kidney phantom, the participants will have either one of three augmented reality markers to show where an expert is looking, or they will not have any visual guidance (standard of care). In all cases, the participants get verbal feedback from the expert surgeon. The goal is to compare the effect of the design of the AR marker on the trainee's performance in exploring the kidney phantom.

Interventions

DEVICEAugmented reality

Augmented reality markers of different designs are tested to evaluate how they affect trainee performance.

Sponsors

Vanderbilt University Medical Center
Lead SponsorOTHER
Vanderbilt University
CollaboratorOTHER
National Institute for Biomedical Imaging and Bioengineering (NIBIB)
CollaboratorNIH

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DEVICE_FEASIBILITY
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
13 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* Urology residents at Vanderbilt University Medical Center

Exclusion criteria

\-

Design outcomes

Primary

MeasureTime frameDescription
Stone Count1-10 minpercentages of stones seen; The NASA Task Load Index (NASA-TLX) assesses participants' subjective workload after completing all tasks under each control method. It includes six dimensions: mental demand, physical demand, temporal demand, performance, effort, and frustration. Each dimension is rated from 0 to 100, with higher scores indicating greater perceived workload. The overall task load index is calculated as the average of the six dimension scores, resulting in a total score ranging from 0 to 100, where higher scores represent greater overall task load.

Secondary

MeasureTime frameDescription
Gaze Metrics1-10 mintotal area of eye gaze seen, Extracted from eye-camera recording from the HoloLens 2
Completion Time1-10 minTime for the stone identification task
NASA Task Load Index1 minConducted after each trial for subjective feedback; Hart and Staveland's NASA Task Load Index (TLX) method assesses work load on five 7-point scales. Increments of high, medium and low estimates for each point result in 21 gradations on the scales. total points 105. mean scores and standard deviation for each arm reported The NASA Task Load Index (NASA-TLX) assesses participants' subjective workload after completing all tasks under each control method. It includes six dimensions: mental demand, physical demand, temporal demand, performance, effort, and frustration. Each dimension is rated from 0 to 100, with higher scores indicating greater perceived workload. The overall task load index is calculated as the average of the six dimension scores, resulting in a total score ranging from 0 to 100, where higher scores represent greater overall task load.

Countries

United States

Participant flow

Recruitment details

All urology residents at Vanderbilt University Medical Center were recruited between 10/14/2024 and 12/31/2024. We enrolled a total of 8 residents. They were contacted directly via email through the urology website.

Pre-assignment details

No significant events occurred between enrollment and assignment of each group.

Baseline characteristics

Characteristic
Age, Continuous32 years
eye gaze metrics, area of interest1295 cm2
STANDARD_DEVIATION 448
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
3 Participants
Race (NIH/OMB)
Black or African American
2 Participants
Race (NIH/OMB)
More than one race
1 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
2 Participants
Region of Enrollment
United States
8 Participants
Sex: Female, Male
Female
4 Participants
Sex: Female, Male
Male
4 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 8
other
Total, other adverse events
0 / 8
serious
Total, serious adverse events
0 / 8

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Apr 21, 2026