In an inspiring breakthrough for both medicine and humanity, Brazilian doctors successfully separated conjoined twins Arthur and Bernardo Lima, who had been joined at the head (a condition known as craniopagus) since their birth in $2018$.

Craniopagus twins are among the rarest forms of conjoined twins, accounting for less than $1$ in $60,000$ births. The condition is notoriously complex due to the twins often sharing critical brain tissue and major blood vessels, making separation extremely high-risk. Arthur and Bernardo, born in Roraima, Brazil, spent nearly four years physically and neurologically connected.

Virtual Reality (VR) Technology: The Key to Precision
The success of this surgery was rooted not just in surgical skill but in technological innovation. More than $100$ medical professionals collaborated in Rio de Janeiro to plan and execute the procedure. What set this operation apart was the pioneering use of cutting-edge virtual reality (VR) technology—a world-first in planning such a surgery.

Surgeons created highly detailed $3\text{D}$ models of the twins’ fused skulls and brains. They then conducted numerous rehearsals in immersive VR simulations, allowing them to practice the complex steps, particularly navigating shared blood vessels and sensitive brain areas, with absolute precision before ever making a real incision.

23 Hours of History and Nine Pre-Surgeries
The separation surgery itself was not a single event, but the culmination of meticulous preparation. Following nine preparatory surgeries, the team embarked on the final operation, a record-breaking procedure that lasted $23\text{ hours}$.

With the aid of the VR images and advanced monitoring systems, doctors navigated the shared vessels and brain tissues with unprecedented accuracy. The surgery demanded unwavering focus and seamless coordination between two surgical teams, one focused on Arthur and the other on Bernardo.

The Human and Medical Significance
The successful separation not only grants Arthur and Bernardo individual lives but also marks a new chapter in neurosurgery and pediatric medicine. The VR planning method has proven highly effective in mitigating risk, especially for complex and rare surgeries.

Following the procedure, the boys are now in recovery. The separation is more than physical; it is the beginning of a new life where each can develop independently. The Lima brothers’ story is a powerful testament to the strength of collaboration, innovation, and the enduring human spirit when facing seemingly insurmountable medical challenges.