PDF(Pubmed)
Abstract：
OBJECTIVE: To explore the feasibility of applying CT Hounsfield Units (HUs) for the assessment of preoperative paraspinal muscle fat infiltration (FI) in different segments in patients who underwent anterior cervical discectomy and fusion (ACDF). To compare the consistency of preoperative paraspinal muscle FI evaluations using MRI and those via CT HUs in patients who underwent ACDF surgery.
METHODS: Ninety-five patients (45 males and 50 females, aged 37‒71 years) who received CT and MRI examinations and underwent ACDF surgery were retrospectively analyzed. In the axial T2-weighted MR images at the median level of the C3/4, C4/5, and C5/6 segments, regions of interests (ROIs) were delineated along the boundaries of the cervical multifidus (MF) and semispinalis cervicis (Scer) muscles. Using the threshold tool in ImageJ software, areas of fat tissue and intermuscular septa within the ROI were quantified. The effective cross-sectional area (ECSA) for each side was obtained by subtracting the areas of fat tissue and intermuscular septa from the total ROI area. The ratio of the fat tissue area to the CSA was then calculated to determine the initial FI value. The depth of subcutaneous fat from the midline spinous process to the epidermis at the median plane of the C4/5 intervertebral disc was measured. The initial FI values were then divided by the depth of fat to determine the post-correction FI value. Using the Picture Archiving and Communication System (PACS), at identical segments and planes, ROIs were delineated using the same method as in MRI under a standard soft tissue window (width of 500 HU, level of 60 HU). The CT HU values were measured within these defined areas. The CT HU values from both sides are summed to obtain the total HU value for the segment. According to whether the measurement results of two sets of data follow a normal distribution, Pearson\'s test or Sperman\'s test was used to analyze the correlation.
RESULTS: On MRI, a statistically significant difference was observed in the post-correction FI only at the C3/4 segment compared to the other two segments (P < 0.05). No significant difference in the post-correction FI between the C4/5 and C5/6 segments was noted (P > 0.05). The CT HU results showed a substantial discrepancy between C3/4 and C4/5 segments and between C3/4 and C5/6 segments (P < 0.05), whereas no statistically significant difference was found in the CT HU value between the C4/5 and C5/6 segments (P > 0.05). The consistency analysis revealed a relatively strong correlation between the post-correction FI and CT HU values of the C3/4 and C4/5 segments. Furthermore, a strong correlation was detected in the variations in the measurement outcomes at the C5/6 segment.
CONCLUSIONS: Patients requiring surgical treatment for the cervical spine exhibit varying degrees of FI in paraspinal muscles across different locations and segments. Evaluating the degree of FI in the paraspinal muscles of the cervical spine through CT HU values is feasible. There is considerable consistency between the post-correction FI assessed under MRI and the measurements of CT HU values in evaluating the FI of paraspinal muscles in the cervical spine.
METHODS: Ninety-five patients (45 males and 50 females, aged 37‒71 years) who received CT and MRI examinations and underwent ACDF surgery were retrospectively analyzed. In the axial T2-weighted MR images at the median level of the C3/4, C4/5, and C5/6 segments, regions of interests (ROIs) were delineated along the boundaries of the cervical multifidus (MF) and semispinalis cervicis (Scer) muscles. Using the threshold tool in ImageJ software, areas of fat tissue and intermuscular septa within the ROI were quantified. The effective cross-sectional area (ECSA) for each side was obtained by subtracting the areas of fat tissue and intermuscular septa from the total ROI area. The ratio of the fat tissue area to the CSA was then calculated to determine the initial FI value. The depth of subcutaneous fat from the midline spinous process to the epidermis at the median plane of the C4/5 intervertebral disc was measured. The initial FI values were then divided by the depth of fat to determine the post-correction FI value. Using the Picture Archiving and Communication System (PACS), at identical segments and planes, ROIs were delineated using the same method as in MRI under a standard soft tissue window (width of 500 HU, level of 60 HU). The CT HU values were measured within these defined areas. The CT HU values from both sides are summed to obtain the total HU value for the segment. According to whether the measurement results of two sets of data follow a normal distribution, Pearson\'s test or Sperman\'s test was used to analyze the correlation.
RESULTS: On MRI, a statistically significant difference was observed in the post-correction FI only at the C3/4 segment compared to the other two segments (P < 0.05). No significant difference in the post-correction FI between the C4/5 and C5/6 segments was noted (P > 0.05). The CT HU results showed a substantial discrepancy between C3/4 and C4/5 segments and between C3/4 and C5/6 segments (P < 0.05), whereas no statistically significant difference was found in the CT HU value between the C4/5 and C5/6 segments (P > 0.05). The consistency analysis revealed a relatively strong correlation between the post-correction FI and CT HU values of the C3/4 and C4/5 segments. Furthermore, a strong correlation was detected in the variations in the measurement outcomes at the C5/6 segment.
CONCLUSIONS: Patients requiring surgical treatment for the cervical spine exhibit varying degrees of FI in paraspinal muscles across different locations and segments. Evaluating the degree of FI in the paraspinal muscles of the cervical spine through CT HU values is feasible. There is considerable consistency between the post-correction FI assessed under MRI and the measurements of CT HU values in evaluating the FI of paraspinal muscles in the cervical spine.
摘要：
目的：探讨应用CTHounsfield单位（HU）评估颈前路椎间盘切除融合术（ACDF）患者术前不同节段椎旁脂肪浸润（FI）的可行性。比较接受ACDF手术的患者术前使用MRI和通过CTHU进行的椎旁肌FI评估的一致性。
方法：95例患者（男45例，女50例，年龄37~71岁)接受CT和MRI检查并接受ACDF手术的患者进行回顾性分析。在C3/4，C4/5和C5/6段的中位数水平的轴向T2加权MR图像中，沿宫颈多裂肌（MF）和宫颈半肌（Scer）肌肉的边界划定了感兴趣区域（ROI）。使用ImageJ软件中的阈值工具，对ROI内的脂肪组织和肌间隔膜区域进行定量.通过从总ROI面积中减去脂肪组织和肌间隔膜的面积来获得每侧的有效横截面面积(ECSA)。然后计算脂肪组织面积与CSA的比率以确定初始FI值。测量C4/5椎间盘正中平面从中线棘突到表皮的皮下脂肪深度。然后将初始FI值除以脂肪深度以确定校正后的FI值。使用图片存档和通信系统（PACS），在相同的段和平面上，在标准软组织窗口（宽度为500HU，60HU的水平）。在这些限定区域内测量CTHU值。将来自两侧的CTHU值求和以获得段的总HU值。根据两组数据的测量结果是否服从正态分布,采用Pearson检验或Sperman检验进行相关性分析。
结果：在MRI上，仅在C3/4节段与其他两个节段相比,在校正后FI中观察到有统计学意义的差异(P<0.05).C4/5和C5/6节段的校正后FI无显著差异(P>0.05)。CTHU结果显示C3/4和C4/5段之间以及C3/4和C5/6段之间存在很大差异（P<0.05）。而C4/5和C5/6段的CTHU值无统计学差异(P>0.05)。一致性分析显示，C3/4和C4/5段的校正后FI和CTHU值之间存在相对较强的相关性。此外，在C5/6节段的测量结果的变化中检测到强相关性.
结论：需要手术治疗的颈椎患者在不同部位和节段的椎旁肌表现出不同程度的FI。通过CTHU值评估颈椎椎旁肌的FI程度是可行的。在评估颈椎椎旁肌的FI时，在MRI下评估的矫正后FI与CTHU值的测量值之间存在相当大的一致性。
方法：95例患者（男45例，女50例，年龄37~71岁)接受CT和MRI检查并接受ACDF手术的患者进行回顾性分析。在C3/4，C4/5和C5/6段的中位数水平的轴向T2加权MR图像中，沿宫颈多裂肌（MF）和宫颈半肌（Scer）肌肉的边界划定了感兴趣区域（ROI）。使用ImageJ软件中的阈值工具，对ROI内的脂肪组织和肌间隔膜区域进行定量.通过从总ROI面积中减去脂肪组织和肌间隔膜的面积来获得每侧的有效横截面面积(ECSA)。然后计算脂肪组织面积与CSA的比率以确定初始FI值。测量C4/5椎间盘正中平面从中线棘突到表皮的皮下脂肪深度。然后将初始FI值除以脂肪深度以确定校正后的FI值。使用图片存档和通信系统（PACS），在相同的段和平面上，在标准软组织窗口（宽度为500HU，60HU的水平）。在这些限定区域内测量CTHU值。将来自两侧的CTHU值求和以获得段的总HU值。根据两组数据的测量结果是否服从正态分布,采用Pearson检验或Sperman检验进行相关性分析。
结果：在MRI上，仅在C3/4节段与其他两个节段相比,在校正后FI中观察到有统计学意义的差异(P<0.05).C4/5和C5/6节段的校正后FI无显著差异(P>0.05)。CTHU结果显示C3/4和C4/5段之间以及C3/4和C5/6段之间存在很大差异（P<0.05）。而C4/5和C5/6段的CTHU值无统计学差异(P>0.05)。一致性分析显示，C3/4和C4/5段的校正后FI和CTHU值之间存在相对较强的相关性。此外，在C5/6节段的测量结果的变化中检测到强相关性.
结论：需要手术治疗的颈椎患者在不同部位和节段的椎旁肌表现出不同程度的FI。通过CTHU值评估颈椎椎旁肌的FI程度是可行的。在评估颈椎椎旁肌的FI时，在MRI下评估的矫正后FI与CTHU值的测量值之间存在相当大的一致性。
