Surgery, particularly intraocular surgery, requires a high degree of manual dexterity that is built over the course of years with consistent practice. The most commonly performed ocular surgery is cataract surgery, which is a remarkable procedure when one considers the dimensional constraints: we make a 2.5-mm incision in a tissue that is less than 1 mm thick, we create a capsulorhexis in a tissue that is just microns thin, and we work within a space that is less than 1 milliliter. The challenge is also that the learning curve is steep.
The standard practice technique involves porcine eyes or synthetic practice eyes in a wet laboratory setting. This works well for surgeons with a baseline level of skill who are self-directed and want to practice something specific. It is more challenging for new surgeons who would benefit from a more defined curriculum, with assessment and testing along the way. In this regard, our residency program invested in a surgical simulator years ago and we require it as part of the training.
The simulator has modules that progress in a stepwise manner, with each subsequent technique building on the previous. At first, the new surgeon gets familiar with looking through the microscope and using the instrumentation in the virtual reality experience. Learning how to pivot within the incision is an important consideration for intraocular surgery. Experienced ophthalmologists do this naturally, and the eye stays in the primary or desired position throughout the surgery. The key benefit of pivoting is that it allows submillimeter precision.
Think of a boat oar, where the rower moves the handle about 1 meter, while the paddle end moves 3 or more meters in the water. Because of the pivoting at the oar-lock, a 3:1 amplification of the movement is generated. For our surgical instruments, it is the opposite, where moving 10 mm outside the eye can result in a tiny 0.5-mm movement of the instrument tip within the eye. This 20:1 reduction of the movement is achieved because the incision acts as the pivot point.
Our surgical simulator teaches this important concept and helps prepare our new residents for their first surgical cases in the operating room. With 2 decades of teaching residents under my belt, I see an improvement in the initial surgical cases with use of the simulator. Keep in mind that it does not obviate the need for practice in the wet laboratory for skills such as suturing with 10-0 grade sutures. I think of the surgical simulator as similar to the racecar driving videogames that I enjoy with my teenage son. They are fun, visually impressive, and based on reality, but they’re not quite the same as actually driving a racecar.