In 2020, Central African Siamese twins conjoined by the head were successfully separated at the Bambino Gesù Pediatric Hospital. It was the first case in Italy – and probably the only one in the world (similar surgeries are not described in the literature) – of successful surgery on a pair of ‘total posterior craniopagus‘, one of the rarest and most complex forms of cranial fusion and cerebral.

Positioned nape to nape, the twins shared the skull and much of the venous system. Over a year of preparation and study with the aid of advanced imaging systems and surgical simulation culminated in three very delicate surgeries.

The last, definitive separation, was performed on June 5th 2020, with an 18-hour surgery and the commitment of over 30 people including doctors and nurses. A month later, the girls were fine, they had just turned 2 and were hospitalized in the Neurosurgery Department of the Holy See Hospital in two beds next to each other, together with their mother.

In July 2018, the President of the Bambino Gesù Children’s Hospital, Mariella Enoc, was on a mission in Central Africa, in the capital Bangui, to follow the expansion works of the pediatric facility commissioned by Pope Francis.

It is there that he meets the newborn twins and decides to take charge of them, bringing them to Rome, to give them a better chance of survival. “When you come across lives that can be saved, it must be done. We cannot and must not look the other way” said President Enoc today during the press conference to present the speech.

Ervina and Prefina had come to light a few days earlier, on June 29th, in the medical center of Mbaiki, a village 100 km from Bangui. No prenatal investigations: the mother Hermine and the doctors discover that it is a pair of Siamese twins only at the time of cesarean delivery. However, the small health center is not equipped to take care of them, so the family is transferred to the Central African capital.

The mother and the twins arrived in Italy on September 10th, 2018, as part of the International Humanitarian Activities of the Pediatric Hospital. After a few months spent at the Bambino Gesù in Palidoro, where they begin the neurorehabilitation process, the little ones are transferred to the Neurosurgery department on the Gianicolo’s Hill for studies on the feasibility of the separation procedures.

The first investigations confirm that the twins are in good general health, the neurological and clinical parameters are normal. However, there is a difference in blood pressure: the heart of one of the girls works harder to maintain the physiological balance of the organs of both, including their brain.

Ervina and Prefina were united by the parietal and occipital region of the skull, i.e. a large surface area of ​​the back of the head which includes the nape.

They shared skull bones and skin; at a deeper level, they shared the falx and the tentorium (fibrous membranes that separate the two cerebral hemispheres and these from the cerebellum) together with a large part of the venous system (the network of vessels responsible for transporting blood used from the brain towards the heart to be re-oxygenated) which represented the most difficult challenge for the Neurosurgery team of the Child Jesus in planning the interventions.

Due to this particular conformation, the little ones fell into the extremely rare category of ‘total’ craniopagus Siamese twins, conjoined, that is, both at the cranial and cerebral level. Many things in common, but not the personality, different and distinct: Prefina playful and lively, Ervina more serious and observant. To make them known, and recognized, even through eye contact before separation, a system of mirrors was used as part of the rehabilitation process.

The big challenge, for the success of the separation, was the cerebral venous system, the network of blood vessels (venous sinuses) that the twins shared in several points. Surgery on the venous structures of the brain is complex and the risk of bleeding and ischemia is high. The Bambino Gesù Children’s Hospital’s Neurosurgery team decided to proceed in steps: three very delicate surgeries to gradually reconstruct two independent venous systems, capable of containing the load of blood traveling from the brain to the heart.

The first surgery. In May 2019, the twins entered the operating room to begin shaping the new autonomous venous structures: the neurosurgeons separated a part of the tentorium and the first of the two common transverse sinuses that were to be assigned to each of the girls; then, with biocompatible materials, they reconstructed a membrane capable of keeping the brain structures divided before the definitive separation.

In June 2019 the second surgery. The team, assisted by the anesthesia group, separated the superior sagittal sinuses (the posterior half of the venous channels that run between the two cerebral hemispheres) and the torcular of Herophilus, or the junction point of the venous sinuses of the brain where all the blood going to the heart. It was a crucial phase: the operating space is a few millimeters and the neurosurgeons proceed with the guidance of the neuronavigator.

On June 5, 2020, a year later, it was time for the definitive separation. The girls have grown up, the new architecture of the veins has consolidated and works; the portion of skin necessary to cover the skull of each of the little ones was expanded with the expanders positioned a few months earlier with a series of plastic surgery operations and the last phase can be started.

A team of over 30 people including doctors, surgeons and nurses was ready in the operating room. The surgery lasted 18 hours: first the skin expanders were removed, then the second transverse sinus and its tentorium are separated; Finally, the bones of the skull that held the two girls together were divided. Once the twins were separated, the surgery continued in two different operating rooms, with two separate teams, to reconstruct the membrane that covers the brain (dura mater), remodel the bones of the skull and recreate the skin lining.

“It was an exciting moment, a fantastic, unrepeatable experience” underlined Carlo Marras, head of Neurosurgery of the Bambino Gesù and of the team that followed the twins. “It was a very ambitious goal and we did everything to achieve it, with passion, optimism and joy. Sharing every step, studying every little detail together”.

Each phase of the twins’ journey was studied and planned with the help of the advanced imaging systems available in the hospital: CT and three-dimensional magnetic resonance imaging, 4D angiography, 3D reconstruction software, neurosimulator.

With these technologies, combined with each other, the skull of the girls was recreated in 3D with all the internal anatomical details, including the vascular network. Simultaneously, it was possible to evaluate the functionality of individual brain structures, quantify blood flow and make a prediction of how the new system would work after the interventions.

The most advanced neuronavigation systems were used in the operating room, particularly useful tools in such complex and rare cases which indicate to the surgeon, with millimeter precision, the position of the most delicate structures.

One month after the definitive separation, the twins were fine. A few days of monitoring in intensive care and then the return to the ward, in the room with two single beds.

On June 29th they celebrated their second birthday, looking into each other’s eyes, moving their little hands to the rhythm of the music, in their mother’s arms. They have passed very difficult surgeries: wounds took time to heal; the risk of infection still present.

They continued the neurorehabilitation program and for a few months and had to wear a protective helmet. But post-op checkups indicated that the brain was intact. The recreated system works, the blood flow has adapted to the new path. “They are in a condition – explained the doctors of the Department of Neuroscience – which will give them the opportunity to grow regularly both from a motor and cognitive point of view, and to lead a normal life, like all girls of their age.”

Their mom Hermine thanked the hospital and all the people who took care of her little girls: “Ervina and Prefina were born twice. If we had stayed in Africa I don’t know what fate they would have had. Now that they are separated and well, I would like them to be baptized by Pope Francis who has always taken care of the children of Bangui. My little ones can now grow up, study and become doctors to save other children.”

The birth of a Siamese couple is a rare event and, among the various types, twins joined at the head (craniopagus) are the rarest: 1 out of 2.5 million live births, 5 cases out of 100,000 twins, especially females . Only a few dozen cases are described in the scientific literature.

The craniopagus is defined as ‘partial‘ when the point of contact between the two heads is limited to the bones and skin, ‘total‘ when the fusion also involves the brain structures and in particular the venous system. Even among the total craniopagus there are differences: the most “common” are the twins joined at the top of the head (vertical craniopagus), rarer are those joined at the nape (posterior craniopagus).

According to available data, until a few years ago, 40% of craniopagus patients died at birth. For the remaining 60%, life expectancy did not exceed 10 years. Until the 1960s, attempts to separate total craniopagus had a mortality rate close to 100%. Subsequently, with technological development and with the introduction of phased surgery, survival, expectation and quality of life have increased.

In the last 20 years, in Europe, there have been reports of only two cases of successfully separated total craniopagus: these are two pairs of twins joined at the top of the head (vertical) operated on in several steps in London. No case described in the literature, however, with the characteristics of the Bangui twins, i.e. total craniopagus joined at the nape (rear).