TY - JOUR
T1 - Standardization of 3-D CT measurements for length and angles by matrix transformation in the 3-D coordinate system
AU - Kitaura, Hideki
AU - Yonetsu, Koichi
AU - Kitamori, Hideki
AU - Kobayashi, Kazuhide
AU - Nakamura, Takashi
PY - 2000/7
Y1 - 2000/7
N2 - Objective: We attempted to establish a new 3-D cephalometry with helical computed tomography (CT) by introducing the matrix transformation of the 3D coordinate system. Subjects and Methods: Three-dimensional cephalometric landmarks on the craniofacial bones were expressed as 3-D vector's originating from the center of the sella. These vectors were standardized by the matrix transformation so that the midsagittal plane and cranial base line coincided with the XZ plane and X axis of the 3-D coordinate system, respectively. We also applied this new method to trace the normal growth of the craniofacial bones in 44 patients with head and neck cancer (age range, 5 to 26 years; 19 women and 25 men). Results: The accuracy for length measurements was less than 3% of standard error of means with a slice thickness of 1 or 3 mm for 28 out of the 29 length measurements recorded. The precision errors by repeated measurements were 0.8% to 1.0% coefficients of variation for intra- and interobserver variability. Standardization of 3-D vectors representing the cephalometric landmarks allowed us to assess successfully the age-related transition of these landmarks of the patients' craniofacial bones. Conclusion: A new assessment method for 3-D CT cephalometry has been developed by standardizing cephalometric landmarks using a matrix transformation of the 3-D coordinate system. This new assessment method may offer potential in planning plastic and reconstructive surgery.
AB - Objective: We attempted to establish a new 3-D cephalometry with helical computed tomography (CT) by introducing the matrix transformation of the 3D coordinate system. Subjects and Methods: Three-dimensional cephalometric landmarks on the craniofacial bones were expressed as 3-D vector's originating from the center of the sella. These vectors were standardized by the matrix transformation so that the midsagittal plane and cranial base line coincided with the XZ plane and X axis of the 3-D coordinate system, respectively. We also applied this new method to trace the normal growth of the craniofacial bones in 44 patients with head and neck cancer (age range, 5 to 26 years; 19 women and 25 men). Results: The accuracy for length measurements was less than 3% of standard error of means with a slice thickness of 1 or 3 mm for 28 out of the 29 length measurements recorded. The precision errors by repeated measurements were 0.8% to 1.0% coefficients of variation for intra- and interobserver variability. Standardization of 3-D vectors representing the cephalometric landmarks allowed us to assess successfully the age-related transition of these landmarks of the patients' craniofacial bones. Conclusion: A new assessment method for 3-D CT cephalometry has been developed by standardizing cephalometric landmarks using a matrix transformation of the 3-D coordinate system. This new assessment method may offer potential in planning plastic and reconstructive surgery.
KW - Coordinate system
KW - Helical computed tomography
KW - Matrix transformation
KW - Three-dimensional cephalometry
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U2 - 10.1597/1545-1569(2000)037<0349:SODCMF>2.3.CO;2
DO - 10.1597/1545-1569(2000)037<0349:SODCMF>2.3.CO;2
M3 - Article
C2 - 10912713
AN - SCOPUS:0033947372
VL - 37
SP - 349
EP - 356
JO - Cleft Palate-Craniofacial Journal
JF - Cleft Palate-Craniofacial Journal
SN - 1055-6656
IS - 4
ER -