Skip to main content

Sustainability took center stage at ESGAR 2023, the annual meeting of the European Society of Gastrointestinal and Abdominal Radiology (ESGAR), as a zoologist highlighted how radiology can help in the conservation of aquatic species last June in Valencia, Spain. 

The world is going through a sixth mass extinction, which is ocurring at a much faster pace than any other similar event in the past, according to Dr. Daniel García Párraga, Director of Zoological Operations at the Valencia Oceanographic, who spoke on the first day of the conference. 

“We are experiencing a very high rate of extinction,” he told a packed audience. “The current rate is between 100 and 1,000 times the background rate of exctinction that should be expected.’’ While domestic mammals and human populations are growing exponentially, the number of wild species is constantly declining, mainly due to human activities.

Image: © pham · 

“Some researchers (have linked) large amounts of emitted CO2 with former extinctions of species,” he said. “Today, human activities generate the largest amounts of CO2 in the atmosphere.” Healthcare and particularly radiology have a big impact on the environment.

“The healthcare sector generates approximately ten percent of the total carbon emissions in the Unites States, a recent study has showed,” he said. “Radiology is thought to be a top contributor to the healthcare carbon footprint due to its high energy-consuming devices and waste from interventional procedures, using on average eight kilograms of material per case.” 

But just as radiology improves and saves human lives, it can also contribute to the conservation of species, he added. 

Helping manage a wide range of animal diseases 

For example, the Imaging Department at La Fe Hospital in Valencia, which is led by former ESGAR President Professor Luis Martí-Bonmatí, cooperates with the Oceanographic to improve the health of aquatic species. “This partnership is a chance to include radiology as an additional tool for saving different species,” García Párraga said. 

One of the most important findings his team has discovered thanks to radiology is the decompression sickness disease (DCS), a debilitating and potentially fatal condition in sea turtles after alterations of their physiological dive when forcibly retained at depth and then brought to the surface. 

X-rays of a healthy turtle, drowned turtle, and turtle with extreme gas embolism. (Image: ©

The researchers have studied DCS in seven marine turtles with both ultrasound and CT. “Ultrasound offers maximum sensitivity to detect gas embolism,” he said. “With the ultrasound device, we discovered that the right atrium is one of the regions where gas bubbles are most easily detected and where they can appear earlier.” 

Establishing severity of the disease is difficult with ultrasound and so the team examined the individuals with CT. “CT is the ideal technique to quantify and characterize in detail the distribution patterns of pathological gas.” 

The main threat for sea turtles remains fishery activities – for example, when turtles get stuck in fishnets. “These activities are the number one accidental cause of death in marine turtles,” he said. “Hundreds of thousands turtles die every year.” 

The Oceanographic carries out research on how to mitigate the impact of fishery on aquatic species. “We work with fishermen to convince them to include exit strategies for turtles in the nets, for example by including a guiding tunnel, grid, and escape opening,” he said. 

García Párraga also tackled the effects of MRI in magneto sensitive species such as turtles, frogs, bats and birds, and detailed how he has worked on active sensing in marine mammals in his talk.