Medical Prototypes For Siamese Twins

SGH approached NYP late October 2000 to build prototypes for a complicated cranial surgery involving Siamese twins with head joined together. Such craniopagus twins is very rare in the world and this is the first time such surgery is to be carried out in Asia.

SGH required 4 sets of prototype for Skin, Skull, Brain and Blood Vessels for the Siamese Twins respectively. As far as possible, each set ideally should have separate parts for each twins, but allow assembly of these twin-parts together for better visualization. Ease and handling these prototypes and verification of mirror images are other factors for consideration. These prototypes must be completed by December for pre-surgical planning. The creation of a medical model consists of two major processes : CAD Reconstruction and Rapid Prototyping. CAD reconstruction involves the conversion and interpolation of 2D images from CT or MRI scans into 3D CAD models.

After the reconstruction of the 3D models, their respective CAD data are transferred to Rapid Prototyping System for the layer-by-layer fabrication of the physical model using nylon composite powder. The project was completed prior to the operation in December 2000.