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- Twins born conjoined at head separated after 40 hours of AI-assisted surgery in historic moment (themirror.com)
Twin sisters Mercy and Goodness, conjoined at the head, have been successfully separated following an extraordinary surgical effort that spanned over 40 hours and incorporated groundbreaking artificial intelligence (AI) technologies.
Born in June 2023 in Nigeria’s Ekiti State, the twins were joined at the skull with shared brain tissue and blood vessels-a rare condition known as craniopagus, which occurs in only about one in every 2.5 million births. Such twins represent just 5% of all conjoined twins, making their case exceptionally uncommon. At six months old, Mercy and Goodness were referred to Gemini Untwined, a UK-based charity specializing in the research and treatment of craniopagus twins.
In 2025, at 19 months of age, the sisters traveled to Abu Dhabi’s SEHA Sheikh Khalifa Medical City for a series of staged medical procedures conducted over four months. A multidisciplinary team of 60 healthcare professionals from the UK, UAE, Brazil, and Nigeria collaborated on the complex separation surgery, which marked the ninth such operation performed by Gemini Untwined. The final separation surgery alone lasted 12 hours, contributing to a total of more than 40 hours of operating time.
Central to the success of the operation was the use of cutting-edge AI and advanced imaging techniques. Detailed brain scans allowed surgeons to rehearse the procedure remotely using mixed reality technology, combining physical and digital environments. The team employed a sophisticated blend of 3D imaging, virtual reality simulation, augmented reality overlays, and ultrasound-guided expansion to carefully map and separate the twins’ shared veins and arteries while minimizing risk to their brains.
Innovative surgical methods were also employed, including an “Open Book” approach that utilized gravity to support the brain and reduce trauma, avoiding the use of traditional steel retractors. Additionally, AI-guided insertion of silicone skin expanders was performed earlier than in previous cases, enabling the twins’ skin to stretch naturally and cover their new skulls without requiring skin grafts.
Professor Noor ul Owase Jeelani, co-founder of Gemini Untwined and lead pediatric neurosurgeon, described the operation as a “landmark” achievement executed with unprecedented precision. He emphasized that the evolving techniques developed through this work not only improve outcomes for craniopagus twins but also contribute to broader advancements in pediatric surgery.
Following a full recovery, Mercy and Goodness have returned home to Nigeria, now able to enjoy life as separated twins with a promising future ahead.