E Guyader1, J Savéan2, C Clodic3, P Letellier4, P Meriot5, R Marianowski6. 1. Service d'ORL et de chirurgie cervico-faciale, hôpital Morvan, CHRU de Brest, 5, avenue Foch, 29200 Brest, France. Electronic address: elsageslin@gmail.com. 2. Laboratoire de traitement de l'information médicale (LaTIM) INSERM UMR 1101, hôpital Morvan, CHRU de Brest, 5, avenue Foch, 29200 Brest, France. 3. Service d'ORL et de chirurgie cervico-faciale, hôpital Laënnec, centre hospitalier de Cornouaille, avenue Yves-Thépaut, 29000 Quimper, France. 4. Service d'odontologie et chirurgie orale, hôpital Morvan, CHRU de Brest, 5, avenue Foch, 29200 Brest, France. 5. Service d'imagerie radiologique, hôpital de La Cavale-Blanche, CHRU de Brest, boulevard Tanguy-Prigent, 29200 Brest, France. 6. Service d'ORL et de chirurgie cervico-faciale, hôpital Morvan, CHRU de Brest, 5, avenue Foch, 29200 Brest, France.
Abstract
OBJECTIVE: To evaluate the accuracy of three-dimensional (3D) Cone Beam Computed Tomography (CBCT) and Computed Tomography (CT) reconstructions of human temporal bones compared with in situ measurements. MATERIAL AND METHODS: Experimental anatomical study of 10 human temporal bones. Wilcoxon's test was used to compare 8 distances on each temporal bone measured in situ and then on 3D CT and CBCT reconstructions. Six landmarks were used: external auditory canal (EAC), tip of the mastoid process, tip of the occiput, zygoma, a point situated 1cm above the tip of the mastoid process (T0) (open technique: lower limit of the mastoidectomy), head of stapes. RESULTS: No significant difference was observed between the 3 measuring techniques for any of the distances studied (P>0.05). DISCUSSION: This study demonstrates the equivalence of CBCT and CT for temporal bone measurements. CONCLUSION: CBCT is a new imaging modality providing 3D reconstructions of the temporal bone that are as reliable as those obtained by CT. As a result of better spatial resolution compared to CT, CBCT is associated with a significantly lower radiation dose. This technique constitutes a morphological progress, as CBCT is comparable to CT, allowing investigation of pathological ears with a lower radiation dose.
OBJECTIVE: To evaluate the accuracy of three-dimensional (3D) Cone Beam Computed Tomography (CBCT) and Computed Tomography (CT) reconstructions of human temporal bones compared with in situ measurements. MATERIAL AND METHODS: Experimental anatomical study of 10 human temporal bones. Wilcoxon's test was used to compare 8 distances on each temporal bone measured in situ and then on 3D CT and CBCT reconstructions. Six landmarks were used: external auditory canal (EAC), tip of the mastoid process, tip of the occiput, zygoma, a point situated 1cm above the tip of the mastoid process (T0) (open technique: lower limit of the mastoidectomy), head of stapes. RESULTS: No significant difference was observed between the 3 measuring techniques for any of the distances studied (P>0.05). DISCUSSION: This study demonstrates the equivalence of CBCT and CT for temporal bone measurements. CONCLUSION: CBCT is a new imaging modality providing 3D reconstructions of the temporal bone that are as reliable as those obtained by CT. As a result of better spatial resolution compared to CT, CBCT is associated with a significantly lower radiation dose. This technique constitutes a morphological progress, as CBCT is comparable to CT, allowing investigation of pathological ears with a lower radiation dose.