If you are considering liposuction, the time you will have to wait before engaging in recreational scuba diving varies on the type of procedure you are going to try. The average wait between the liposuction and your first dive will usually be between three weeks and three months, depending on the amount of fatty tissue removed and which type of liposuction you opt for.

Recovery time also depends on how many areas of your body you decide to focus upon. For example, if you have three areas of your body that you feel need improvement, you could either have three separate procedures or one much more prolonged one. If you opt for the latter, you only require one period of recovery, but that period will be longer, and the procedure itself will be longer and will carry more relative risks. The risks involved with general anesthesia also increase the longer you are subject to it. If you have all three areas dealt with on separate occasions, the risks will be lessened but you will have three separate recovery periods to undergo before you can return to scuba diving

Smart liposuction techniques, which are a form of laser liposuction, have shorter recovery periods. Smart liposuction involves incisions so small that there is no need for stitches, and there is less of a need for a general anesthetic, so the recovery from this aspect of the surgery is also accelerated. Smart liposuction is most commonly used for small areas of the body, such as the chin, so recovery times are much shorter.

Vaser liposuction uses a particular kind of ultrasonic liposuction in order to perform minimally invasive procedure. Ultrasonic liposuction works by sending precisely-targeted ultrasonic waves to break up fat cells in the body so that they can be easily removed. Again, the small size of the incisions used also help speed up recovery time. However, the process of ultrasonic liposuction takes more time to complete, lengthening the time you will spend under the knife. As well as vaser liposuction, other forms of ultrasonic liposuction exist, so it is best to consult your doctor before deciding which is best for you. Typically it takes one month to recover sufficiently from vaser liposuction before you can try scuba diving, because the aftercare from the procedure involves wearing compression dressings for at least one month.

You can aid your own recovery after having liposuction by making sure that you drink plenty of water to avoid dehydration, and by resting for at least a full week before you try to return to normal life. This initial period of rest will give your body a chance to recover, meaning that your overall recovery time will improve .

The ability of light to pass through water (and our ability to see clearly) is also influenced by its turbidity. Turbidity is influenced by many factors but they can be grouped into two large classes, things suspended in the water and things dissolved in the water. Suspended things include silt, plankton, etc. while dissolved things include salt and chemicals. When a diver is swimming along near the bottom, the water movement caused by their fins often stirs up the silt and for a while the water behind them has high turbidity this often results in death when open water divers enter caves. The water is crystal clear in front of them and they do not realize until they turn around that they have been kicking up the silt and they can no longer see the way out of the cave.

If the water is still, the silt will eventually settle back down to the bottom and the water will become clear once again. The time this process takes depends upon the size of the silt particles. Grains of sand will settle in a minute or two while the ultra fine grains of rock flour produced by a glacier will take several weeks to completely settle out. During a cave diving trip under the Columbia Ice fields in 1987 the water was ‘air clear’ when we arrived at the dive site. After we had made the area safe and several hundred (or thousand) kilograms (pounds) of mud and rocks had been dropped into the water, the visibility was less than 2.5 cm (I inch)! We went back to the surface and returned to the dive site two days later. The silt was so fine (glacial flour) that even though the water was absolutely still, the visibility had only improved to 30 cm (12 inches).

Salt water has large quantities of salt and other chemicals dissolved in it and for this reason, can never he as clear as fresh water. The best clarity to be found in the ocean would be around 60 meters (200 feet) while in some fresh water caves the water is so clear it cannot be seen, visibility is over 300 meters (1,000 feet). These ideal conditions are rarely encountered and we usually have much less visibility. For example, the Ottawa River contains water with many dissolved chemicals (from soil, trees, etc.) and visibility is seldom more than 6 meters (20 feet). The St. Lawrence River used to be similar but the infestation of billions of zebra mussels has changed this situation drastically. Zebra mussels are filter feeders and each mussel filters the silt and chemicals out of a large amount of water every day. The result is that places where 6 meters (20 feet) visibility used to be considered good now frequently have 30 meters (100 feet) visibility or snore. The problem is, now that the water is clear enough for divers to see well, the wrecks still can’t be seen because they are now covered in many layers of zebra mussels!

The eye is really just a complex, living camera. The main parts of the eye are the cornea, the iris, the lens, and the retina. The cornea is clear and has no blood supply It protects the eye but its main function is to focus the light that enters the eye on the retina. A diopter is a measure of the power of a lens and the power of the cornea is equivalent to a +43 diopter lens. It is composed of five layers but for simplicity can be thought of as having a thin layer on the surface (epithelium) and a body composed of flat stromal cells. The epithelium has many nerve endings and therefore, when we get a hair or some other foreign body in the eye and scratch the cornea, it hurts a great deal!

After passing through the cornea, light crosses the anterior chamber and then goes through the opening in the iris called the pupil. The iris is a muscle and forms the colored part of the eye so that when we say someone has blue eyes or brown eyes, we are really saying that their iris is blue or brown. The iris functions the same as the aperture in a camera; it leaves a large opening when the light is dim and a small opening when the light is bright. This controls the amount of light that enters the posterior part of the eye.

When we are excited or frightened the pupil dilates, allowing more light into the eye and allowing us to see more clearly. Men consider women more beautiful if they have larger pupils (they assume the woman is excited to see them!). Women in ancient Egypt used to rub juice from the belladonna plant (contains the drug atropine) in their eyes to dilate the pupils to make themselves appear more beautiful!

Light has to be ‘bent’ just the right amount so that it is focused on the retina for us to see clearly. Light from objects that are far away has to be ‘bent’ less than light from near objects. The purpose of the lens is to change the refractive power of the eye to accommodate for objects at different distances. As the ciliary muscles contract, they release the tension on the suspension ligament of the lens and the natural elasticity of the lens capsule causes it to assume a more rounded

shape. In a normal eye light from distant objects is focused on the retina with the biliary muscles relaxed. To focus the light from near objects, the colliery muscles contract and the lens becomes rounder, increasing the focusing power of the eye.

When light hits the retina, a series of chemical changes occur which generate an electrical signal that is transmitted to the brain and through a very complex process translated into the images we see. Now that we have a basic understanding of hose the eye works, what happens when we try and see underwater?