Diving with "posterior vitreous separation"

[gert7to3]

Here's a retinal image showing vitreous retraction.

 

[DocVikingo]

Very interesting.

Thanks, Gert.

DocVikingo

 

[Cacia]

thanks! do they dilate you for that one?

I was wondering, if there are any diving eye conditions related to small bubbles hitting the tiny vessels of the retina, like what happens in the cochlea?

Does a diagnosis of vitreous retraction put you at any higher risk for retinal seperation?

 

[gert7to3]

With OCT dilation isn't always necessary, but it is usually done in the course of a dilated examination. You wouldn't normally have OCT performed unless there was some condition that needed to be documented. Glaucoma is the most common problem a general ophthalmologist would follow with OCT.

The Dx is vitreous separation. I used the word retraction, but just as a descriptive term.

The only diving issue I can think of which would cause bubbles in the blood stream would be severe DCS. I remember reading a description of guy with really bad DCS where his blood samples were foaming from retained gas...he died. If you're in that kind of a situation, a branch retinal artery occlusion is the least of your worries.

Vitreous separation is a normal aging process. Severe complications can be dealt with.

 

[DocVikingo]

The only diving issue I can think of which would cause bubbles in the blood stream would be severe DCS. I remember reading a description of guy with really bad DCS where his blood samples were foaming from retained gas...he died.

Hi Gert,

Actually, it's not quite that simple.

Doppler-detected "bubbles in the blood stream" are quite common upon ascent from SCUBA and the vast majority of divers show no signs or symptoms of decompression illness (DCI). More specifically, these bubbles are venous gas emboli (VGE) induced by nitrogen desaturation. For example, see: "The incidence of venous gas emboli in recreational diving; Undersea Hyperb Med. 2002 Winter;29 (4):247-59

The primary issue is when the release of nitrogen is too rapid and problematic bubbles form in the tissues or in the blood stream.

The former is termed decompression sickness (DCS). In this phase inert gases can result in foreign body immune responses, intravascular clotting and vessel occlusion due to pressure.

The latter is called arterial gas embolism (AGE). While AGE most often is the result of pulmonary barotrauma, venous bubbles also can enter arterial circulation via other mechanisms of arterialization across the pulmonary vasculature or as a result of patent foramen ovale (PFO). Once a bubble mass has crossed over, it can lodge and impede blood flow. This is of particular concern when they lodge in coronary or cerebral arteries.

The adverse implications of either event are obvious.

Moreover, the likelihood of obtaining post-dive blood samples, either venous or arterial, "foaming from retained gas" seems quite remote for several important reasons. But, in the event that such was found the person indeed would immediately die.

Regards,

DocVikingo

 

[gert7to3]

DocVikingo thanks for the clarifications on DCI vs. DCS vs. AGE.

The incident I was referring to was the father/son team who dove that recently discovered U boat off New Jersey. Perhaps the Shadow Divers book? I only read an excerpt. They got turned around on a penetration dive of the U boat, breathing air at around 180', didn't find their deco tanks and had to surface. The father expired on the diveboat and the son died in hospital. Nitrogen outgassing was described as visibly bubbling out of the son's blood samples.

 

[ssimpala]

To all who responded to my inquiry - We had an excellent week of diving, Thanks to the answers I received from you and DAN, I was able to relax and enjoy! This forum is a great resource for divers and is much appreciated.

 

[Gene_Hobbs]

For example, see: "The incidence of venous gas emboli in recreational diving; Undersea Hyperb Med. 2002 Winter;29 (4):247-59

Article:
Dunford, Vann, Gerth, Pieper, Huggins, Wacholtz, and Bennett. The incidence of venous gas emboli in recreational diving. Undersea Hyperb Med. 2002 Winter;29 (4):247-59
RRR ID: 3773

gert7to3, given your profession, I thought these might interest you as well...

Mekjavic, Campbell, Jaki, and Dovsak. Ocular bubble formation as a method of assessing decompression stress. Undersea Hyperb Med. 1998 Winter;25(4):201-10.
RRR ID: 2299

Bennett, Doolette, and Heffernan. OCULAR TEAR FILM BUBBLE COUNTS AFTER RECREATIONAL COMPRESSED AIR DIVING. Undersea Hyperb Med. 2001 Spring;28(1):1-7.
RRR ID: 2361

Rogelj, Mekjavic, and Mekjavic. Ocular tear film bubble formation following air, heliox and nitrox dives. 2004 UHMS abstract.
RRR ID: 1411

 

[Peter Guy]

TSandM suggested I write about my own experience(s), for what they are worth (which isn't much!).

I can't remember when I first experienced the "flashes" but it has been quite some time. I have numerous "floaters" -- one of which is quite large (large enough to periodically block effective vision in my right eye).

The only negative effect from this for my diving (at least an effect of which I'm aware) is that periodically I can't see/read the gauge on my right hand (depth/time). For that reason alone I refuse to replace my Cobra with an SPG. I know I always have a backup depth/time instrument that I can read with my left eye when the right one goes funky. (And to think the FAA thought I shouldn't fly!)

 

[Moving Target]

Gert7to3 I see you are still active so forgive me for bringing up an old post but I had the same scans done today as well as some additional photos and was diagnosed with a branch retinal vein occlusion. I am headed to see a specialist on wednesday and will heed his advice, however as many have experienced most MDs are not familiar with the effects of diving on such issues. Have you heard anything from your coworkers regarding this issue and diving?