Tetralogy of Fallot
Recently I was moved to help create a model for a fellow Tweeter who had a newborn boy with the rare congenital cardiac abnormality known as Tetralogy of Fallot. He was born at 39 weeks, with the diagnosis made in utero, and the parents were facing unprecedented healthcare bills due to the US insurance system.
I asked for the CT scans to be sent over, and set to work on creating this model.
The paediatric heart is about 4cm at it's widest point, with tributary vessels only a millimetre or so. Getting good quality CT data with contrast within the arteries is an incredible technical feat. The newborn must be sedated and the airway intubated in order to be scanned. The scan must be performed perfectly, timed to the racing heart beat, using minimal radiation to avoid any damage to the surrounding sensitive newborn organs.
The images from the scan were of sufficient quality to produce this exquisitely accurate model, the first of it's kind as far as I am aware. The model is a 3D visualisation of the blood within the cardiac chambers and vessels of this tiny but vital organ in a newborn.
It allows the viewer to examine the four key traits of Tetralogy of Fallot: A right-sided aortic arch, pulmonary stenosis, right venticular hypertrophy, and a ventricular septal defect. The model also demonstrates the withered ductus arteriosus, known as the ligamentum arteriosum.
I also created a 3D-printable version of this model (non-profit, charges are for materials and delivery only). Due to the technical specifications of 3D printing the smaller tributary arteries and vessels cannot be printed, as they are too fragile to be supported. The printed model can be held in your palm, and demonstrates the key traits of this congenital condition.
Thankfully, a central shunt has been placed surgically, and I am told the little boy is doing well. He is expecting definitve surgery in the next 6 months.
My thanks and best wishes go out to his parents, and I wish them and their son all the best for the future.