Hey guys, thanks for the feedback.
I have actually spoken with my Retinal Surgeon. She's not really familiar with the type of vibration experienced by riding on rough gravel road, but had made a recommendation that I play it extra safe, which is to avoid the activity due to the risk of having a PVD in the middle of a race. The thought behind her recommendation is when a PVD happens, it's critical to have the eye examined by a Retina Specialist right away to ensure that there is no retinal detachment.
I agree with everyone. Since the risk is involving eyesight, I'd rather play it safe and avoid joining any gravel grinding race in the near future (at least until the PVD completes and my surgeon gives me a green light to race).
Thanks,
Richard