Modification of Kong's Lateral Canthotomy Simulation Trainer for Added Realism and Tonometry Practice

Lateral canthotomy with cantholysis is an emergency procedure that relieves critically elevated intraocular pressure. This procedure is uncommon, so opportunities to observe or practice it on a live patient are limited. There is a spectrum of accessible, inexpensive simulation models available for practicing the procedure. One innovative trainer uses a table tennis ball as the globe, a rubber band as the canthal tendon, and foam tape as skin. We modified this model by replacing the table tennis ball with an endotracheal tube cuff. This allowed learners to practice measuring intraocular pressure with a handheld applanation tonometer as an independent procedure and as part of performing a lateral canthotomy. The cuff provided a realistic tactile feel. The cuff may rupture if handled improperly, reinforcing the importance of careful technique. Successful procedural completion is signaled by a measurable decrease in intraocular pressure. We share our modifications in this article and describe users' experience with the trainer as reported in a survey. The trainer improved learners' comfort with both tonometry and lateral canthotomy with cantholysis. We used our trainer in a teaching session with 53 participants who completed a pre- and post-session Likert scale survey. Median comfort level for performing tonometry before the session improved from 4/5 (somewhat comfortable; IQR: 3-5) to 4.5/5 (somewhat comfortable/very comfortable; IQR: 4-5, P = 0.002) after the session. Median comfort level for performing lateral canthotomy with cantholysis before the session improved from 2/5 (somewhat uncomfortable; IQR: 1-3) to 4/5 (somewhat comfortable; IQR: 3-4, P < 0.00001) after the session. Our modifications to the trainer increased the cost from 5 US$ to 15 US$. Emergency medicine and ophthalmology educators may find our modified model to be a helpful teaching tool for this rare procedure.