World-leading craniofacial surgery for midface hypoplasia at Mediclinic Louis Leipoldt

Posted on 16 August 2017

Midface hypoplasia is a congenital facial anomaly in which the upper jaw, cheekbones, and eye sockets remain underdeveloped in newborn infants. The condition obstructs proper breathing and can lead to complications over time.

Surgery has traditionally been reserved for older children before Prof Graewe at Mediclinic pioneered the development of a less invasive procedure in infants, called Midface Distraction without Osteotomies. The results are a radical reduction in operating time, a substantial reduction in blood loss, less time in Critical Care, a significantly lowered risk of repeat procedures and less facial scarring from incisions.

‘The midface is underdeveloped in patients with midface hypoplasia so they often cannot breathe properly and may have comorbidities such as obstructive sleep apnea and chronic respiratory tract infections,’ says Prof Frank Graewe, niche plastic and reconstructive surgeon at Mediclinic Louis Leipoldt who is also involved as a consultant at the craniofacial unit at Tygerberg Hospital on a pro bono basis. ‘As they get older, because of the overload on the lungs, the right heart starts dilating which, if untreated, eventually leads to heart failure.’

Traditionally, a Midface Distraction is a technique performed on children over the age of four. The upper jaw, cheeks, nose, and orbital rims are moved forward with osteotomies (cutting into the bones) from different incisions in the face and skull and held in place with plates and screws.

‘This was often traumatic for children, who were aware of the ordeal, as it involved a four-hour operation with a great deal of blood loss. Because surgeons had to cut through the bone, the growth centres in the bone were damaged – and after the operation, the growth of the mid-face bones was even worse than before the surgery. This resulted in the need for another advancement when the patient became a teenager,’ says Prof Graewe.

Another procedure was subsequently developed, where the face wasn’t advanced in a single procedure. Distraction (pulling the two ends of the bone apart) Osteogenesis (new bone formation between the two ends) subsequently became the standard of care. The bone was cut, and the gap was left for a few days; the surgeons then used a distraction device and the face was slowly pushed forward, allowing new bone formation in the gap between the bones.

However, Prof Graewe soon realised that by performing the surgery on infants when their skulls are still soft and malleable, he could drastically reduce the risk of blood loss, complications and morbidity. He developed these findings further together with Prof Jean Morkel, head of maxillofacial surgery at the University of the Western Cape, and gave the treatment a name: Midface Distraction without Osteotomies (published in the International Journal of Craniofacial Surgery).

‘Midface Distraction without Osteotomies is only for very specific cases, limited to very young children and infants,’ explains Prof Graewe. ‘Your distractor works on two points, so in order to address craniofacial deformities with a midface hypoplasia, you need rigid fixation on two sides. For one side, we insert a small Steinman pin, acting as a stabilising mechanism for the midface, through the cheekbones just under the eyes and nose (trans-zygomatically). For older children the other side is secured with pins in the skull. But you can’t do that with an infant because if you drill into the skull you quickly reach the brain. So for infants, Prof Morkel custom makes a footplate that is attached to the outside of the temporal region of the skull with very short screws,’ explains Prof Graewe. ‘This serves as the second point of attachment.’

‘After the operation, the midface is slowly pushed forward by turning the small wheel on the external midface distraction device by half a millimetre every day for just over a month,’ he says. ‘This gives us an advancement of about 2 cm, stretching the bones almost as you would stretch a stick of gum.’

Follow-up CT scans also reveal that rather than destroying the bone’s growth potential, the procedure had the opposite effect, and the bones continue to grow unaided.

‘After the operation, the CT scans may reveal a ‘chewing gum-like’ appearance, where bones look elongated and thin but eventually they become thick and strong as it goes through the remodelling process,’ he says.

The first patient Prof Graewe operated on using this technique was an infant who presented with midface hypoplasia without an identifiable underlying genetic condition. She was intubated from birth due to upper airway obstruction.

The surgeons were able to remove the tracheotomy tube in the same operation in which they removed the distraction device because it had resolved the breathing obstruction.

A postoperative CT scan showed further bone growth of 2.6 mm during the consolidation period which concludes about four month after the removal of the device.

The World Craniofacial Foundation refers volunteer cases from the rest of Africa to Prof Graewe and Prof Morkel. After performing over a dozen of these cases successfully over the past 9 years, the surgeons most recently operated on a 15-month-old baby from Nigeria called Somtu, who was born with Crouzon Syndrome. This syndrome is a rare genetic disorder characterised by the premature fusion of certain skull bones as well as other characteristic external features. The operation was declared a success and Somtu remained at Mediclinic as an outpatient.

Postoperative photo of Somtu

The alternative surgeries, such as Distraction Osteogenesis, are still reserved for older children who for various reasons require midface distractions later on in life. Some patients, especially syndromic cases, have severely affected bone growth and in spite of this very early intervention, they might still need more corrective surgery at a later age.

About Prof Frank Graewe

Prof Frank Graewe is a plastic and reconstructive surgeon as well as a skilled microsurgeon practising in Cape Town, Munich and Windhoek. In addition to his pioneering work in craniofacial surgery, he was an integral part of the team that performed the world’s first penile transplant at Tygerberg Hospital in 2014 and is a pioneer in adipose derived stem cells in plastic surgery.