Plastic Surgery Research

The Vascular Biology unit works closely with the Department of Plastic and Maxillofacial Surgery at The Royal Children’s Hospital. The focus of the vascular biology laboratory is on vascular anomalies - localised collections of abnormally formed blood and/or lymphatic vessels which can affect any part of the body. 

The group’s current research aims to identify genetic causes of vascular anomalies, determine the functional effects of those genes in healthy and diseased vessels and identify potential targets for new therapies.

Cleft lip and palate is the most common birth anomaly. Surgery gives excellent results, but problems with growth of the facial skeleton can occur. Pierre-Robin Sequence (PRS), a condition in which cleft palate with undergrowth of the jaw leads to problems with breathing, is a particular focus of research.   

Group Leaders: 
Group Members: 
Prof Nicky Kilpatrick
Role: 
Clinical research leader
Dr Rod Phillips
Role: 
Clinician researcher
Theresa Connor
Role: 
Research Assistant
Harry Matthews
Role: 
Imaging researcher

Propranolol resistance in infantile haemangioma
Haemangioma – or birth mark – is a common benign tumour of infancy which appears soon after birth. It affects about 10 per cent of Caucasian newborns. In most cases it regresses spontaneously, but sometimes these tumours can cause complications if found at a site important for body function, such as the airway or eye. Haemangioma of infancy likely to cause such complications is treated with propranolol. In most cases this treatment is highly successful but about 10 per cent of children do not respond to it. The goal of this clinical and lab –based research is to understand why this occurs.

The biology of lymphatic malformations
Lymphatic malformations are localised collections of cystic structures filled with lymphatic fluid. They are often found in the head and neck region, although they can affect any part of the body. Current management is based on surgery and radiology, however these cannot completely eradicate this condition and no drug treatment is available. The group’s research in this area aims to identify and understand the cause and consequence of this condition. This will enable the researchers to identify specific targets for therapies and develop specific treatments. In addition, researchers are developing ways to analyse the mechanisms by which the identified gene abnormality leads to the development of lymphatic malformations.

Regulation of cell death in childhood lymphatic malformations
Lymphatic malformations are a type of vascular malformation comprised of cystic spaces filled with lymph fluid and lined by lymphatic endothelial cells. The group’s recent work demonstrated that lymphatic malformation endothelial cells are better able to tolerate exposure to staurosporine, a molecule that induces cell death. The results show endothelial cells from these lymphatic abnormalities are more resistant to cell death than normal control lymphatic endothelial cells. This raises the intriguing possibility that there are differences in the expression or function of proteins that regulate apoptosis – cell death – which characterise lymphatic malformations. This project investigates the balance between pro-apoptotic and anti-apoptotic proteins regulating the survival of lymphatic malformation endothelial cells.

The role of angiopoietin family in the pathogenesis of lymphatic malformations
Vascular anomalies are developmental abnormalities affecting the blood and lymphatic vascular systems in up to 10 per cent of newborns. Lymphatic malformations (LMs) are more common types of vascular anomalies characterised by large localised collections of multiple cystic spaces lined by lymphatic endothelium. The cause of LMs is unknown. Using immunohistochemistry, protein analysis, and in vitro cell culture assays, the researcher in this study will examine the role of angiopoietins and their receptors, called TIE receptors, in the formation of human LMs.

Genetics of capillary malformation and response to laser
Capillary malformation (Port Wine stain) is generally evident at birth, and remains discoloured without treatment. In a proportion of cases there is a gradual overgrowth of the involved soft tissue which continues into adulthood. Laser is the most effective treatment, but not all capillary malformations respond equally and it is not clear if early laser treatment can prevent later overgrowth. A recent study reported about 90 per cent of capillary malformations may be caused by a somatic point mutation in the gene GNAQ. This project will test two hypotheses: i) the presence and density of the GNAQ mutation may be predictive for response to laser, and that the 10 per cent of cases without the mutation may account for a significant proportion of the non-responders to laser and ii)  GPCR activity may account for the overgrowth seen in capillary malformations.

Pierre Robin Sequence
Pierre Robin Sequence (PRS) is generally recognised as cleft palate, retrognathia (overbite?) and respiratory obstruction, but exact definitions vary and consensus on treatment is lacking. The group is currently completing a retrospective review and accurate phenotyping of a cohort of patients with PRS. Future studies will involve genetic studies, particularly of the SOX9 gene, and prospective evaluation of a range of clinical outcomes in PRS patients. Researchers hope to establish a national registry of PRS patients to answer important questions about the best treatment.  

Fathers’ experience of cleft diagnosis
The diagnosis of cleft lip in a newborn child, whether made on ultrasound before birth or at the time of birth can have a major impact on parents. This is a qualitative study which aims to assess and understand the impact of cleft diagnosis, and the manner in which the information is delivered and followed up, on fathers of cleft children.  Results will inform future practice in antenatal diagnosis and genetic counselling.

The oral health of children with clefts of the lip and/or palate
This is a retrospective study of the oral health outcomes of children who attend the Melbourne Cleft Service. It will provide a snapshot of the oral health status of children currently under the care of the RCH cleft service and allow comparison of the oral health status of this cohort with a control group statewide.

Participating in Cleft Research: The family perspective
The aim of this project is to understand the experience of parents of children born with a cleft lip and/or cleft lip and palate in their involvement as a family in genetic research. Interviews were held with parents (together or individual) who had participated in OzCleft (a genotype:phenotype cleft study). This project identified clear benefits to the non-cleft affected family members of participating in research as well as a lack of understanding of the genetic implications of being born with CL/P.

Normal face and head shape in children: The AHEAD study
The shape of children’s heads and faces change markedly through normal growth and development. The aim of reconstructive face and cranial surgery is to restore the normal shape to children but to do this it is vital to understand what variation there is in normal head shape. This study is collecting 1,900 3D photographs of normal Victorian children to create a database of normal head growth. Sophisticated computer analysis will allow us to define how children’s heads and faces grow and change through childhood which will in turn allow us to understand how disease and injury can affect head shape.  

Collaborations: 
  • Prof Joyce Bischoff, Karp Family Research Laboratories, Boston Children’s Hospital, USA
  • Prof Andrew Elefanty, Murdoch Children's Research Institute
  • Prof Paul Evans, Department of Cardiovascular Science, University of Sheffield, England
  • Prof Steven Fishman, Boston Children’s Hospital, USA
  • Professor Amanda Fosang, Murdoch Children's Research Institute
  • Prof Christina Mitchell, Monash University, Melbourne
  • Assoc Prof Geraldine Mitchell, O’Brien Institute, Melbourne
  • Dr Lorelai Schoemaker, Department of Neurosurgery, Stanford University
  • Prof Michael Simons, Yale University School of Medicine
  • Prof Miikka Vikkula, de Duve Institute and Université catholique de Louvain, Brussels, Belgium
  • Dr Ben Hogan, School of Biomedical Sciences, University of Queensland
  • Dr Peter Claes, Medical Imaging KULeuven, Belgium
  • Prof John Clements, Melbourne Dental School, University of Melbourne