“In movies, the forensic pathologist always goes to the scene, examines the deceased and immediately states the exact time of death. It doesn’t work like that in real life. Determining the time of death is a very complex issue,” says Sünne Remmer, head of the Northern Estonian Forensic Medical Department, forensic pathologist and radiology expert.

Her department, located at EKEI’s main building in Tallinn, is the largest of Estonia’s four forensic pathology departments. It handles approximately half of all forensic autopsies in the country, totaling around 600-700 per year.

EKEI Northern Estonian Forensic Medical Department. Source: Ken Mürk/ERR

Unlike hospital autopsies, forensic autopsies are required when the cause of death is not an illness but an external factor. “Trauma, accidents, falls and suicides are the cases we handle. We also deal with poisonings – whether from alcohol, drugs, carbon monoxide or fires,” explains Remmer.

Occasionally, individuals who have died from illnesses are also sent for autopsy if there is lingering suspicion that the death may have involved trauma. “A large part of our work is verification: did the person really die in the way it is believed?” the expert notes.

Autopsy without cutting

The ground floor of the Estonian Forensic Science Institute’s main building houses one single-person and three double-person autopsy rooms, along with four cold chambers that can accommodate up to 30 bodies. The rooms are situated at ground level to facilitate the easy transportation of bodies in and out of the building.

However, not all deceased individuals are brought to the autopsy room. According to Sünne Remmer, the work of forensic experts is aided by a computed tomography (CT) scanner and a magnetic resonance imaging (MRI) machine, both located on the same floor.

EKEI Northern Estonian Forensic Medical Department. Source: Ken Mürk/ERR

“In Estonia, our forensic medicine technology is in quite good shape. We started using radiology for deceased individuals in 2010, and in recent years, we’ve been able to completely upgrade our equipment,” notes Remmer. The CT scanner is particularly effective for examining the bones of the deceased, while the MRI scanner is better suited for detecting soft tissue injuries, such as bruises and damage to internal organs.

When a body is examined solely using radiological equipment, it is referred to as a digital autopsy. “In some cases, a digital autopsy is entirely sufficient,” says Remmer. Since September 2023, a legislative amendment allows certain autopsies to be performed without physically opening the body. For now, fully digital autopsies at EKEI remain in the experimental stage, with experts practicing and the police getting accustomed to the method. “We haven’t received any negative feedback from the police,” Remmer notes.

Currently, digital autopsies are conducted only in specific cases involving severe trauma, based on agreements with the police. These include incidents such as train accidents or falls from great heights, where the injuries are visibly evident. “Digital imaging reveals all major internal injuries, but some details are not as clearly visible. That’s why we select cases where such details are not critical,” explains Remmer. She adds that the imaging technology is better at detecting injuries than illnesses. “If we suspect the cause of death is a disease, we still perform a full autopsy,” she says.

As in radiological examinations of living individuals, contrast agents are sometimes necessary for deceased bodies as well. According to Remmer, injuries to blood vessels and internal organs are much more visible with the use of contrast agents. “Since the deceased lack circulation, the contrast agent doesn’t move through the body on its own. A pump is required for this,” she explains.

Not all deceased individuals are brought to the autopsy room, as the work of forensic experts is facilitated by radiological equipment located on the same floor. Source: Ken Mürk/ERR

Since pumps specifically designed for administering contrast agents to deceased bodies are expensive, the department sought a more affordable alternative. “Our colleague Andreas-Christian Hade built a system for us using an aquarium pump and a bottle,” explains Remmer. The pump is connected to the body’s major veins and arteries using thick cannulas. In addition to standard cannulas, the department has also experimented with custom 3D-printed cannulas. “We pump in the contrast agent and the imaging quality improves immediately,” she notes.

Modern technology has also made remote work during autopsies possible. In certain cases, a small tissue sample is taken from the body and prepared on a slide for microscopic examination, which helps determine the timing of injuries. “Now, we can also perform digital histology. We scan these slides into the computer, allowing us to examine them on a screen instead of using a microscope – even from home,” she explains.

Time of death

According to Sünne Remmer, the most challenging issue in forensic medicine is determining the time of death. Currently, this is done by assessing the degree of rigor mortis and measuring the body temperature of the deceased. “However, these methods don’t provide absolute certainty, as many environmental factors can influence the results,” she explains. To address this, the department is conducting two research projects aimed at developing new methods for determining time of death.

In one project, vitreous humor fluid is extracted from the deceased’s eye. The concentrations of two substances – potassium and hypoxanthine – are measured and the data is entered into a mathematical model to estimate the approximate time of death. Remmer notes, however, that formulas developed in one country may not work as well in another. “We’ve observed that the formula we are developing ourselves performs slightly better on our cases than those found in the literature,” she compares.

The second project utilizes the spectroscopy feature of the existing MRI machine. According to Remmer, this function can detect metabolic byproducts in the human brain and present them as a spectrum. “This spectrum varies depending on whether the person has recently died or has been deceased for a longer time,” she explains. During the project, experts compare the spectra of individuals who died at different times to identify patterns that correlate with the time of death.

Ideally, Remmer envisions a future where a combination of methods is used. “This would involve a mathematical model where you input markers from vitreous humor, the metabolic spectrum from the brain and, for example, body temperature. The model would then provide the most likely time-of-death range,” she speculates.

Crisis preparation underway

The number of forensic autopsies performed in Estonia has been steadily declining over the years. “Currently, about 1,400-1,500 are conducted annually, which is a relatively small number,” notes Sünne Remmer. In the Northern Estonia Forensic Pathology Department, an average of 50 autopsies are performed per month, though this figure varies significantly.

“When the weather is nice, people are more active and we see all kinds of sports-related accidents. During holidays, there’s often an increase in suicides. If a new drug enters the market, we immediately see a spike in drug-related deaths,” she explains.

A drug-related death of a young person with no visible injuries is the quickest type of autopsy, taking about an hour to complete. In contrast, an autopsy on a victim of a severe traffic accident or homicide, where there are numerous injuries, can take several hours. “The preparatory phase of a physical autopsy – photographing, washing and opening the body – alone takes about 30 minutes,” Remmer explains. Additional time is required if blood or urine samples need to be collected during the procedure. After the examination, the body must be carefully sutured to prepare it for transfer to the funeral home.

The number of forensic autopsies conducted in Estonia has been steadily decreasing. Source: Ken Mürk/ERR

As a recent innovation, microphones have been installed above each table in the autopsy room. During the autopsy, the expert starts a recording program on the computer and narrates all injury and pathology findings aloud. “Currently, we still transcribe these recordings manually, but soon we’ll implement automatic speech-to-text transcription. The pathologist will need to speak clearly,” Remmer adds with a smile.

Experts also make use of digital tools before and after autopsies, with significant assistance coming from the Health Portal, according to Remmer. If required for the investigation, EKEI experts have the right to review the deceased’s prior health records.

“For instance, if I suspect that an injury was caused during a recent assault or if it predated the incident, I can check whether the person had undergone any medical examinations and whether the injury was documented,” Remmer explains.

Another emerging focus for the forensic medicine department is preparing to handle situations involving mass casualties, such as those caused by war or natural disasters. “We’ve participated in and organized several training sessions and drills, including a large-scale exercise – Crevex 2023. In cases where there are numerous unidentified deceased individuals, our role is to ensure that each one is correctly identified,” explains Remmer.

In such scenarios, EKEI plans to rapidly process all the deceased through a CT scanner to create descriptive files for each victim, allowing for more detailed examination later. “Thankfully, we don’t have much practical experience with such cases here, but we have taken steps to prepare,” she adds.