title: Normative inner ear volumetric measurements.
abstract: In the current study, we attempted to determine normative inner ear volumetric measurements generated from three-dimensional computed tomography (CT) images. In addition, we investigated a correlation between the axial length and the volume of the labyrinth and discussed clinical outcomes of this correlation. Amira 5.2.2 software was used to create three-dimensional isosurface images of the human labyrinth using two-dimensional CT images from 35 anatomically normal patients. With the three-dimensional labyrinths, complete dimensional analysis was performed to gain insight into both the volume and the greatest axial length of the inner ear. Paired t test and Pearson correlation were used. Our volume of the inner ear inquiry reported a mean volume of 221.5 with SD of 24.3 μL (0.228 μL for males and 0.218 μL for females). The length showed a mean of 1.713 cm with SD of 0.064 cm (1.753 cm for males and 1.695 cm for females). The length was used to estimate the volume, and the estimates were within 10% of the measured volume 74.3% of the time. Normative volumetric measurements of the inner ear can be obtained by using three-dimensional CT Imaging by Amira 5.2.2 software. There was a statistically significant positive correlation between the axial length of the labyrinth and the volume of the labyrinth. The axial length of the labyrinth could be used to estimate the volume of the labyrinth, which may be clinically important to estimate the concentration of the drug distributed in the inner ear.
authors.affiliation: From the *Thomas Jefferson University, Philadelphia, Pennsylvania; †Christiana Care Health Systems, Newark, Delaware; ‡Loma Linda Medical Center Loma Linda, California; §Colden & Seymour ENT and Allergy, Newburyport, Massachusetts; ∥University of Delaware, Newark, Delaware; ¶Division of Otolaryngology-Head and Neck Surgery, Saad Specialist Hospital, Al-Khobar, Saudi Arabia; and #Division of Otolaryngology-Head and Neck Surgery, College of Medicine, The Pennsylvania State University, Hershey, Pennsylvania.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Teixido
authors.forename: Gary
authors.initials: G
authors.lastname: Kirkilas
authors.forename: Peter
authors.initials: P
authors.lastname: Seymour
authors.forename: Kanik
authors.initials: K
authors.lastname: Sem
authors.forename: Alberto
authors.initials: A
authors.lastname: Iaia
authors.forename: Omar
authors.initials: O
authors.lastname: Sabra
authors.forename: Huseyin
authors.initials: H
authors.lastname: Isildak
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003051:Cochlea / Q000000981:diagnostic imaging; D007758:Ear, Inner / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000295:instrumentation; D009929:Organ Size; D012665:Semicircular Canals / Q000000981:diagnostic imaging; D012737:Sex Factors; D012984:Software; D015898:Tomography Scanners, X-Ray Computed; D014057:Tomography, X-Ray Computed / Q000379:methods; D014722:Vestibule, Labyrinth / Q000000981:diagnostic imaging; D055815:Young Adult