Semmes-Murphy Clinic, Memphis, Tennessee, USA.
Department of Neurosurgery, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Children's Foundation Research Institute, Le Bonheur Children's Hospital, Memphis, Tennessee, USA.
World Neurosurg. 2023 Aug;176:e380-e383. doi: 10.1016/j.wneu.2023.05.066. Epub 2023 May 24.
Diagnosis of Chiari I malformation (CM-1) is based on measurements of the inferior extension of the cerebellar tonsils into the foramen magnum on cranial or cervical spine magnetic resonance imaging. Imaging may be obtained before the patient is referred to the neurosurgical specialist. The length of time raises questions about the possibility that body mass index (BMI) fluctuations could affect the measurement of ectopia length. However, previous literature on BMI and CM-1 has reported conflicting findings on BMI.
We conducted a retrospective chart review of 161 patients who were referred to a single neurosurgeon for CM-1 consultation. Patients with multiple recorded BMI values (n = 71) were compared to see if BMI changes correlated with changes in ectopia length. In addition, we compared and tested 154 recorded ectopia lengths from the patients (1 per patient) and patient BMI values with Pearson correlation and Welch t tests to determine if BMI changes either influenced or were associated with ectopia changes.
For the 71 patients with multiple BMI values, change in ectopia length ranged from -4.6-9.8 mm but was not statistically significant (r = 0.019; P = 0.88). For the 154 measured ectopia lengths, changes in BMI did not correlate with ectopia length (P > 0.05). Likewise, differences in ectopia length between patients in normal, overweight, and obese categories were not statistically significant (|tstat| < |tcrit|, P > 0.05).
In individual patients, we found that BMI and changes in BMI were not accompanied by changes in tonsil ectopia length.
Chiari I 畸形（CM-1）的诊断基于小脑扁桃体在颅颈磁共振成像下进入枕骨大孔的下延程度。在将患者转介给神经外科专家之前，可能会获得影像学检查结果。时间的长短引发了疑问，即体重指数（BMI）波动是否可能影响异位长度的测量。然而，先前关于 BMI 和 CM-1 的文献报告称，BMI 存在相互矛盾的发现。
我们对 161 名被转诊给单一神经外科医生进行 CM-1 咨询的患者进行了回顾性图表审查。比较了有多个记录 BMI 值的患者（n=71），以观察 BMI 变化是否与异位长度变化相关。此外，我们还比较和测试了 154 名患者（每位患者 1 个）的记录异位长度和患者 BMI 值，使用 Pearson 相关系数和 Welch t 检验来确定 BMI 变化是否影响或与异位变化相关。
对于 71 名有多个 BMI 值的患者，异位长度的变化范围为-4.6-9.8mm，但无统计学意义（r=0.019；P=0.88）。对于 154 个测量的异位长度，BMI 的变化与异位长度没有相关性（P>0.05）。同样，正常、超重和肥胖类别的患者之间的异位长度差异也无统计学意义（|tstat|＜|tcrit|，P＞0.05）。
在个体患者中，我们发现 BMI 及其变化并未伴随扁桃体异位长度的变化。
