[1] The other changes in the eyes, in the immediate post-mortem phase, include loss of intraocular pressure and the clouding of the cornea. The intraocular pressure decreases drastically after death and reaches 4 mmHg or less within 6 hours after death.
Changes of the Eye Following Death
Following death, potassium accumulates inside vitreous humor. The buildup of potassium may be used to estimate the time of death.
After death, there is are no reflexes of the pupils to light and the cornea also loses its reflex. The cornea of the deceased also become cloudy after two hours of death. Besides that, the pressure in the eyes start to decrease and the eyeballs become flaccid before it they sink into the orbits of the eyes.
Upon death the cornea slowly becomes hazy. The change in corneal opacity is believed to be secondary to the change in hydration and architectural destruction of the collagen fiber network, functional alteration of corneal endothelium, disregulation of proteoglycan hydration and ion concentration in corneal stroma.
Between a half hour to three hours after death, the eyelid loses its elasticity, the pupil dilates and there is a distinct change in the cornea, which is normally transparent. The exact timing of these changes depends on the state of the eyes (open or closed), ambient temperature, and humidity.
For approximately the first 3 hours after death the body will be flaccid (soft) and warm. After about 3-8 hours is starts to stiffen, and from approximately 8-36 hours it will be stiff and cold. The body becomes stiff because of a range of chemical changes in the muscle fibres after death.
Here is a brief summary of the changes that happen in the body in the hours and days after death: One hour: Relaxation of muscles (primary flaccidity) starts right away, followed by the skin becoming pale.
About two hours after death, the cornea becomes hazy or cloudy, turning progressively more opaque over the next day or two. This obstructs the view of the lens and back of the eye. (See A New Look at a Dead Retina, on page 80.) But this clouding may provide a rough estimate in helping to determine time of death.
Your muscles loosen immediately after death, releasing any strain on your bowel and bladder. As a result, most people poop and pee at death. Your skin may also sag, making it easier to see your bone structure beneath.
24-72 hours after death — the internal organs decompose. 3-5 days after death — the body starts to bloat and blood-containing foam leaks from the mouth and nose. 8-10 days after death — the body turns from green to red as the blood decomposes and the organs in the abdomen accumulate gas.
Eyes become cloudy
After death, the eye not only looks as if it sees past you, but the very look of the eye itself changes. Around two hours after death, the cornea becomes cloudy. Over the following several days, the cloudiness turns eyes opaque.
[2] The cornea begins to cloud within 2 hours after death and usually prevents intra-ocular examination with an ophthalmoscope. [3] The skin loses its elasticity and luster within the first few hours after death and appears pale.
The organ of vision contains a particular substance, retinal purple, on which is imprinted in their exact form these images. They have even been perfectly reconstituted when the eye, after death, is removed and soaked in an alum bath.
Post-Mortem Biochemistry
These chemicals include lactic acid, hypoxanthine, uric acid, ammonia, NADH and formic acid. This type of analysis can be used to help diagnose various different types of deaths such as: drowning, anaphylactic shock, hypothermia or any deaths related to alcohol or diabetes.
THE POSTERIOR PART OF THE EYE ONLY
The obvious reason is that the eye is left cosmetically normal for viewing by relatives, although important macular or retinal disease can be examined by the pathologist. We advise, however, that the eye should be removed intact using other methods, if at all possible.
After someone dies, it's normal to see or hear them. Some people also reporting sensing the smell or warmth of someone close to them, or just feel a very strong sense of their presence. Sometimes these feelings can be very powerful. They may be comforting but also feel disturbing.
As the blood pools, patches appear on the skin within 30 minutes of death. About two to four hours postmortem, these patches join up, creating large dark purplish areas towards the bottom of the body and lightening the skin elsewhere. This may be less apparent on darker skin. This process is called livor mortis.
It's through the chest cavity that the doctor removes the tongue and windpipe. After removal, the doctor carefully examines all of the internal organs one at a time. The mortician then carefully cuts the scalp and saws through the skull to examine parts of the brain.
The underlying principle is as follows: Certain species of flies lay their eggs in the tissue of a corpse as early as one to two hours after death. A few days later, maggots hatch and grow in size with each passing day.
And if the body is floating in water less than 70 degrees Fahrenheit (21 degrees Celsius) for about three weeks, the tissues turn into a soapy fatty acid known as "grave wax" that halts bacterial growth. The skin, however, will still blister and turn greenish black.
By 50 years in, your tissues will have liquefied and disappeared, leaving behind mummified skin and tendons. Eventually these too will disintegrate, and after 80 years in that coffin, your bones will crack as the soft collagen inside them deteriorates, leaving nothing but the brittle mineral frame behind.
The immediate aftermath of dying can be surprisingly lively. For the first few minutes of the postmortem period, brain cells may survive. The heart can keep beating without its blood supply. A healthy liver continues breaking down alcohol.
Physical signs
Facial muscles may relax and the jaw can drop. Skin can become very pale. Breathing can alternate between loud rasping breaths and quiet breathing. Towards the end, dying people will often only breathe periodically, with an intake of breath followed by no breath for several seconds.
An accurate time of death also can help rule out possible suspects who may have been somewhere else when the death occurred and a more general time range could create a larger window for someone's alibi. This information can be used in court to establish a case.