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Updated: Jun 28, 2025

Discovering Middle Ear Anatomy by Transcanal Endoscopic Ear Surgery: A Dissection Manual
Published on: January 11, 2018
Three-dimensional reconstruction of King Henri IV's paranasal sinuses and mastoid cells
Robin Baudouin1,2, Angélique Amelot3, Isabelle Huynh-Charlier2,4
1Department of Otolaryngology-Head & Neck Surgery, Foch Hospital, Suresnes, France.
Purpose:
The preserved head of King Henri IV of France (life 1553-1610, reign 1589-1610) has survived to the present day thanks to high-quality embalming and favorable conservation conditions. The aim of this study was to examine Henry IV's upper resonant cavities and mastoids using an original and innovative forensic three-dimensional segmentation method.
Methods:
The paranasal sinuses and mastoid cells of King Henri IV of France were studied by cross-referencing available biographical information with clinical and flexible endoscopic examination and computed tomography (CT-scan) imaging. The paranasal sinuses and mastoid cells were delineated and their volumes were assessed using ITK-SNAP 4.0 software (open-source). Graphical representations were created using Fusion 360® (Autodesk Inc., San Rafael, CA, USA) and MeshMixer® (Autodesk Inc., San Rafael, CA, USA).
Results:
Paranasal sinus tomodensitometry revealed abnormalities in shape and number. Henri IV of France suffered from sinus aplasia. Neither the left sphenoid nor left frontal sinus contrasted sharply, and a remarkable pneumatization of the right clinoid processes extended throughout the height of the right pterygoid process. The total volumes of Henri IV's mastoid air-cells were estimated at 27 and 26 mL, respectively, for the right and left sides, exceeding the normal mean and the maximum of modern subjects by a wide margin. No sign of chronic ear or sinus condition was found.
Conclusions:
An innovative method has been developed in forensic medicine to establish hypotheses about the growth and respiratory conditions of the face.

