Uosyte Raimonda, Shaw Darren J, Gunn-Moore Danielle A, Fraga-Manteiga Eduardo, Schwarz Tobias
Royal (Dick) School of Veterinary Studies & The Roslin Institute, The University of Edinburgh, Roslin, Midlothian, Scotland, EH25 9RG, UK.
Vet Radiol Ultrasound. 2015 Sep-Oct;56(5):494-502. doi: 10.1111/vru.12263. Epub 2015 Apr 13.
Turbinate destruction is an important diagnostic criterion in canine and feline nasal computed tomography (CT). However decreased turbinate visibility may also be caused by technical CT settings and nasal fluid. The purpose of this experimental, crossover study was to determine whether fluid reduces conspicuity of canine and feline nasal turbinates in CT and if so, whether CT settings can maximize conspicuity. Three canine and three feline cadaver heads were used. Nasal slabs were CT-scanned before and after submerging them in a water bath; using sequential, helical, and ultrahigh resolution modes; with images in low, medium, and high frequency image reconstruction kernels; and with application of additional posterior fossa optimization and high contrast enhancing filters. Visible turbinate length was measured by a single observer using manual tracing. Nasal density heterogeneity was measured using the standard deviation (SD) of mean nasal density from a region of interest in each nasal cavity. Linear mixed-effect models using the R package 'nlme', multivariable models and standard post hoc Tukey pair-wise comparisons were performed to investigate the effect of several variables (nasal content, scanning mode, image reconstruction kernel, application of post reconstruction filters) on measured visible total turbinate length and SD of mean nasal density. All canine and feline water-filled nasal slabs showed significantly decreased visibility of nasal turbinates (P < 0.001). High frequency kernels provided the best turbinate visibility and highest SD of aerated nasal slabs, whereas medium frequency kernels were optimal for water-filled nasal slabs. Scanning mode and filter application had no effect on turbinate visibility.
鼻甲破坏是犬猫鼻腔计算机断层扫描（CT）的一项重要诊断标准。然而，鼻甲可视性降低也可能由CT技术参数设置和鼻腔积液引起。本实验性交叉研究的目的是确定积液是否会降低犬猫鼻腔鼻甲在CT中的显影效果，如果是，CT参数设置能否使显影效果最大化。使用了三个犬类和三个猫类尸体头部。将鼻骨切片浸入水浴前后进行CT扫描；采用序列扫描、螺旋扫描和超高分辨率模式；使用低、中、高频图像重建内核进行图像重建；并应用额外的后颅窝优化和高对比度增强滤波器。由一名观察者使用手动追踪测量可见鼻甲长度。使用每个鼻腔感兴趣区域的平均鼻腔密度标准差（SD）测量鼻腔密度异质性。使用R软件包“nlme”进行线性混合效应模型分析、多变量模型分析以及标准的事后Tukey成对比较，以研究几个变量（鼻腔内容物、扫描模式、图像重建内核、重建后滤波器的应用）对测量的可见鼻甲总长度和平均鼻腔密度标准差的影响。所有犬类和猫类充满水的鼻骨切片均显示鼻甲可视性显著降低（P < 0.001）。高频内核提供了最佳的鼻甲可视性以及充气鼻骨切片的最高标准差，而中频内核对于充满水的鼻骨切片最为理想。扫描模式和滤波器应用对鼻甲可视性没有影响。
