Normative inner ear volumetric measurements.

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.

Volumetric MRI and MRS and early motor development of infants born preterm.

PURPOSE: To investigate the relationship between volumetric magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) in infants born less than 30 weeks gestation and early motor development at 6 months adjusted age. METHODS: Twenty infants born preterm and 4 born at term (control) underwent MRI with volumetric analysis and MRS prior to neonatal intensive care unit discharge. Infants were assessed using the Bayley Scale of Infant Development at 6 months adjusted age. RESULTS: At 6 months, infants born preterm with low motor scores had a reduction in their subcortical gray matter. No differences were detected in other brain structures. N-acetylaspartate/choline correlated with white matter (R = 0.45, P = .03), gray matter (R = 0.43, P = .04), and cerebellar volume (R = 0.6, P = .002) but not with 6-month motor performance. CONCLUSION: There is an association between diminished subcortical gray matter volume and low motor scores. Our data suggest that volumetric MRI performed prior to hospital discharge may have some role in counseling parents about potential motor delays.