IRIS Project: Paving the Way for Zero-Gravity Medicine

A team of radiologists and researchers has successfully performed a nephrostomy—a procedure used to drain the kidney—in microgravity, marking a significant step toward medical autonomy for astronauts on long-duration space missions.

The experiment was conducted between March 17 and March 19, 2026, aboard a zero-G aircraft operated by Novespace in Bordeaux, France. The initiative, known as Project IRIS (Interventional Radiology In Space), aimed to test whether minimally invasive radiological techniques could be adapted to the constraints of weightlessness.

Addressing Critical Risks in Space Medicine

Urinary disorders, particularly infections and renal colic, represent a major health risk for astronauts. Currently, therapeutic options in space are limited primarily to medications. If a condition requires a more complex intervention, the only viable solution is often an emergency return to Earth, a process that can cost several million euros.

« Les astronautes savent faire du diagnostic en repérant les problèmes physiologiques dans le corps, mais s’il y a besoin de thérapeutique, ils n’ont pas grand-chose, à part des médicaments. » Docteur Imago

By testing the feasibility of a nephrostomy in a weightless environment, Project IRIS seeks to provide a way to treat these conditions without the need for heavy surgery or general anesthesia, which are impractical in space.

Collaborative Research and Execution

The project was a collaborative effort involving the Centre National d’Études Spatiales (CNES), the Société Française de Radiologie (SFR), and the Fédération de Radiologie Interventionnelle (FRI). The tests were part of the broader SpaceshipFR project, which is preparing for future manned spaceflights.

The medical team involved in the zero-G flights included:

• Dr. Éva Fourage from CHU de Bordeaux
• Pr. Vincent Vidal from AP-HM
• Dr. Jérôme Soussan from AP-HM
• Pe. Julien Frandon from CHU de Nîmes
• Guillaume Louis, a radiologist
• Jessica Studer from MEDES
• Cyrille Muller

During the flights, the team focused on the drainage of the ureter in a simulated case of renal colic complicated by superinfection. Researchers analyzed the precision of the gestures, the manipulation of medical instruments, and the behavior of fluids in microgravity to determine how these practices must be adapted for extreme environments.

Implications for Deep Space and Earth

The ability to perform interventional radiology in space is viewed as essential for the success of future missions to the Moon and Mars, where the distance from Earth makes immediate evacuation impossible. Developing these mini-invasive techniques allows for a higher degree of medical self-sufficiency for crews traveling far from terrestrial hospitals.

Beyond space exploration, the findings from Project IRIS may have practical applications on Earth. The researchers noted that these simple, effective, and minimally invasive techniques could be deployed in isolated regions or medical deserts, providing an alternative to surgery for populations living far from major medical centers.