Development of a low-cost strabismus surgery simulation model

An automated process for bulk downloading optical coherence tomography scans

OBJECTIVE

To develop an automated method for efficiently downloading a large number of optical coherence tomography (OCT) scans obtained using the Heidelberg Spectralis (Heidelberg Engineering, Heidelberg, Germany) platform.

METHODS

The electronic medical records and OCT scans were extracted for all patients with age-related macular degeneration treated at the Hadassah University Hospital Retina Clinic between 2010 and 2021. A macro was created using Visual Basic for Applications (VBA) and Microsoft Excel to automate the export process and anonymize the OCT scans in accordance with hospital policy. OCT scans were extracted as proprietary Heidelberg E2E files.

RESULTS

The VBA macro was used to export a total of 94,789 E2E files from 2807 patient records, with an average processing time of 4.32 min per volume scan (SD: 3.57 min). The entire export process took a total of approximately 202 h to complete over a period of 24 days. In a smaller sample, using the macro to download the scans was significantly faster than manually downloading the scans, averaging 3.88 vs. 11.08 min/file, respectively (t = 8.59, p < 0.001). Finally, we found that exporting the files during both off-clinic and working hours resulted in significantly faster processing times compared to exporting the files solely during working hours (t = 5.77, p < 0.001).

CONCLUSIONS

This study demonstrates the feasibility of using VBA and Excel to automate the process for bulk downloading data from a specific medical imaging platform. The specific steps and techniques will likely vary depending on the software used and hospital constraints and should be determined for each application.

Low-cost simulator for intra-abdominal bleeding

BACKGROUND

training in critical surgical situations is crucial for a safe outcome. The use of simulators is well established, although many are quite expensive, requiring the search for financially viable solutions for training centers.

METHODS

we built a low-cost simulator for intra-abdominal bleeding with inexpensive materials, such as a manikin chest, latex tubes, silicone rubber, and waterproof fabric, seeking to mimic the abdominal viscera and vessels and their anatomical correlations. An IV infusion set allowed simulated blood to flow under pressure, and the blood flowed freely during simulation. After obtaining a functional model, we selected general surgeons to validate the simulator and its use in teaching surgery. We used the content validity index (CVI), with a cutoff of 0.9.

RESULTS

the cost of building the prototype was US$71,00 in 2021, accounting for the purchase of the various necessary materials. Twelve raters participated in the validation tests. The results obtained from the feedback survey showed a good evaluation of all items, especially the recognition of the injured vessel, access to the vascular injury, hemostasis by manual compression, and hemostatic suturing.

CONCLUSION

the proposed simulator obtained good results in scenarios of intra-abdominal bleeding from large vessels, as well as for hemostasis by manual compression and suturing. It proved to be a useful tool for training in critical intra- abdominal bleeding situations, while maintaining a low cost of building.

Making Headway in Surgical Education at Home and Abroad: Use of an Inexpensive Three-Dimensional Learning Model to Improve Plastic Surgery Resident Confidence in Mohs Defect Assessment and Closure Planning

BACKGROUND

The development of simulation, particularly low-cost models, has become a focus of interest within plastic surgery education. Current simulators for Mohs reconstruction are either expensive or not reusable. The authors hypothesize that using a Styrofoam head model during an interactive teaching session will positively affect plastic surgery trainee comfort in designing Mohs reconstructive options.

METHODS

A cohort of integrated plastic surgery residents at a single institution performed a preactivity questionnaire to obtain baseline comfort in defect assessment and design for five Mohs defects. They subsequently underwent an interactive learning session and were instructed to design flaps on life-size Styrofoam heads with feedback from the senior author (M.L.B.). A postactivity questionnaire was completed to assess improvement in comfort in defect assessment and flap design. Three attending surgeons then compared trainee designs with the senior author's design to assess accuracy. All surveys were based on a five-point Likert scale.

RESULTS

When analyzing all defects, average postactivity scores increased by 0.63 (SD, ±0.24) ( P = 0.008). Junior residents ( n = 8) had a greater increase in average score responses [mean, 1.07 (0.5 to 1.75)] compared with senior residents ( n = 9) [mean, 0.27 (0 to 1)] ( P < 0.001). When assessed by senior-level surgeons, senior residents had significantly greater accuracy in design for each defect ( P < 0.05) except cheek advancement flap ( P = 0.08).

CONCLUSION

Participation in an interactive educational activity using a Styrofoam head model demonstrated significant improvements in trainee assessment and design of reconstructive options for Mohs defects.

Systematic review of simulation-based education in strabismus assessment and management

BACKGROUND

Strabismus is a dynamic condition for which simulation-based training is valuable, given the variable complexity and relatively reduced exposure compared with other ophthalmic presentations. This study assessed the performance of simulation models available for medical training in the assessment and management of strabismus.

METHODS

A systematic review of relevant peer-reviewed academic databases was conducted, without publication date restrictions. English-language publications evaluating the performance of simulation models for education on strabismus were included. Risk of bias was assessed using the Cochrane RoB-2 tool and CLARITY Risk of Bias Instrument for Cross-Sectional Surveys of Attitudes and Practices. Validity of evidence was evaluated using the Kirkpatrick framework.

RESULTS

Of the total 3,298 citations exported for title and abstract screening, 54 advanced to full-text screening, and 7 were included in final review. Model types were either dry (2), wet (4), or virtual reality (1). All models were deemed to be successful, but few standardized parameters were specified. Costs of models ranged from a few dollars (ball and wood), to moderate (non-cadaveric), to costly (virtual reality). All studies scored a moderate or high risk of bias, and the majority (4/7) of studies scored level 1 on the Kirkpatrick scale.

CONCLUSIONS

Research on simulation for strabismus assessment and management is limited and varied for model fidelity and testing audiences. All models were deemed individually successful compared to non-simulation-based teaching methodologies, although no direct comparisons were made. The limited evidence available suggests that low-fidelity and low-cost models can be used for trainees without sacrificing educational quality.

Quality assessment of polymer materials for human model eye development

PURPOSE

We developed model eyes using six polymer materials to determine which materials were most appropriate in simulating real human sclera and extraocular muscle (EOM).

METHODS

Five three-dimensional (3-D) printed polymers (FlexFill, PolyFlex, PCTPE, Soft PLA, and NinjaFlex) and one silicone material were systematically tested by board-certified ophthalmologists and senior ophthalmology residents. Material testing included scleral passes with 6-0 Vicryl sutures through each eye model. Participants completed a survey designed to collect demographic data, subjective assessment of each material's accuracy in simulating real human sclera and EOM, and a ranking for each polymer material to identify which would be most suitable for an ophthalmic surgery training tool. The Wilcoxon signed-rank test was conducted to determine if there was a statistically significant difference in the distribution of ranks between the polymer materials.

RESULTS

The distribution of ranks for silicone material's "sclera" and "EOM" components were statistically significantly higher than that of all other polymer materials (all p < 0.05). Silicone material received the highest rank for both "sclera" and "EOM" components. Survey results indicated that the silicone material effectively simulated real human tissue.

CONCLUSION

Silicone model eyes performed better than 3-D printed polymers as an educational tool for incorporation into a microsurgical training curriculum. Silicone models provide a low-cost teaching tool that allows for independent practice of microsurgical techniques without requiring a wet-laboratory facility.

Real-time artificial intelligence evaluation of cataract surgery: A preliminary study on demonstration experiment

PURPOSE:

We demonstrated real-time evaluation technology for cataract surgery using artificial intelligence (AI) to residents and supervising doctors (doctors), and performed a comparison between the two groups in terms of risk indicators and duration for two of the important processes of surgery, continuous curvilinear capsulorhexis (CCC) and phacoemulsification (Phaco).

MATERIALS AND METHODS:

Each of three residents with operative experience of fewer than 100 cases, and three supervising doctors with operative experience of 1000 or more cases, performed cataract surgeries on three cases, respectably, a total of 18 cases. The mean values of the risk indicators in the CCC and Phaco processes measured in real-time during the surgery were statistically compared between the residents’ group and the doctors’ group.

RESULTS:

The mean values (standard deviation) of the risk indicator (the safest, 0 to most risky, 1) for CCC were 0.556 (0.384) in the residents and 0.433 (0.421) in the doctors, those for Phaco were 0.511 (0.423) in the residents and 0.377 (0.406) in the doctors. The doctors’ risk indicators were significantly better in both processes (P = 0.0003, P < 0.0001 by Wilcoxon test).

CONCLUSION:

We successfully implemented a real-time surgical technique evaluation system for cataract surgery and collected data. The risk indicators were significantly better in the doctors than in the resident's group, suggesting that AI can objectively serve as a new indicator to intraoperatively identify surgical risks.

Simulation of complex strabismus surgical procedures on goat eyes

PURPOSE

To describe the possibility of complex strabismus surgical simulation on goat eyes.

METHODS

The goat eyes were procured from local slaughterhouse with retained extra ocular muscle tissues. The obtained eyes were inspected for globe integrity, muscle quality, muscle length, and the surrounding teno-conjunctival layers. The included eyes were then segregated for surgical simulation based on their insertion and orientation (as oblique or recti), and they were mounted on a mannequin head, with a fixation suture at free end to simulate the resting tension. Additionally, as per necessary, extra muscles were also transplanted along desired sites to simulate human extra ocular muscle anatomy.

RESULTS

The inferior oblique, superior oblique, and all other four recti were successfully simulated in varying proportions in more than 50 eyes. Primarily, by simulating the lateral rectus, inferior rectus, and the inferior oblique muscle, staged weakening procedures of inferior oblique were successfully practiced (Fink's recession, Park's recession, Elliot and Nankin procedure, total anterior positioning, and antero-nasal trans-position or Stager's procedure). Similarly, by simulating superior rectus, inferior rectus, lateral rectus, and the medial rectus muscles, half width transposition, full width transposition, and other complex procedures were practiced (Knapp's procedure, augmented Knapp's, Nishida's procedure, Faden operation, and Y splitting procedure). Furthermore, by simulating superior oblique and the superior rectus muscles, superior oblique tuck, posterior tenectomy, loop tenotomy, and Harada Ito procedures were successfully practiced.

CONCLUSIONS

On goat eyes, the complex strabismus surgical procedures can be successfully simulated and practiced after re-organizing the existing muscles in different patterns.