Maxillary sinus, Great work of Leonardo da Vinci!

Leonardo da Vinci is one of the greatest painters of all time.  Among his works, the Mona Lisa is his most famous. Although, he is famous as one of the greatest ever painters, he was an expert anatomist too.  As an oral and maxillofacial surgeon, I have always been especially interested in his anatomical works.  The Vitruvian Man, the drawing of Roman architect, is the icon of human body proportion.  Facial plastic surgeons strive for the golden facial ratio he demonstrated through his drawings.  

Interestingly, there is another story regarding his anatomical works.  He is the first person to describe the maxillary sinus.   His work on the maxillary sinus is very significant indeed.  Size, shape, location are all perfect in his drawings.  The relationships between the sinus and the teeth and the nasal cavity are also amazingly precise.  I wonder how he did the accurate dissections in the 15^th century using only primitive knifes and saws?  In my opinion, he is a true genius!