
July 4, 2004
Complications, Other
Question from Byram, Mississippi, USA:
I have had two operations on my right eye and one on my left eye for retinopathy and the last one was October 20, 2003. I am wondering how SCUBA diving will affect me and if I am at some risk that I may be unaware of. I just had an examination from my eye surgeon on June 22, 2004 and everything looks great. He suggested that I not go any deeper than thirty feet since the most pressure changes happen within the first 30 feet. He said it was okay with him as long as I didn’t go any deeper than thirty feet. What complications will I be faced with if something does happen? Will the pressure cause more damage to my eyes and if so, what kind?
Answer:
This is an excellent question. The primary risk of SCUBA diving in a patient with established diabetic retinopathy stems from poor vascular perfusion, i.e. reduced blood flow within retinal tissue, a phenomenon from which every patient with proliferative diabetic retinopathy suffers. Reduced retinal perfusion increases the risk of decompression sickness (“the bends”) occurring within the retina, as the body is less able to remove excess dissolved nitrogen from retinal blood vessels and tissue. This could lead to precipitation of nitrogen bubbles that further damage already compromised retinal vasculature, leading to increased retinal hemorrhaging and retinal capillary non-perfusion that might reinitiate growth of abnormal blood vessels, the sine qua non of proliferative diabetic retinopathy.
Hyperglycemia “sludges” blood flow and may additionally increase the risk of decompression sickness. The bends occur primarily below of depth of 30 feet, hence your surgeon’s recommendation. I would further recommend that your last A1c prior to diving be below 7.0%.
PC