Objectives

It was reported that the XYZ/2 technique (using length, width and height of hematoma) is a simple and reliable method of estimation of chronic subdural hematoma volume. Two subtypes of techniques enable to adequately estimate, it is unclear which is more accurate. Computer-assisted volumetric analysis is widely considered the gold standard for CSDH volumetric analysis. It is important to consider the stability of analyses between examiners, because individual, decision-making differences may be relevant to the analysis, as hematoma margin and length are hand-operated. In this study, we investigated potential measurement biases of three neurosurgeons and analyzed the validity of the XYZ/2 technique by comparing it to the gold standard method.

Method

We retrospectively analyzed CT scans that indicated the need for an operation in 50 patients with CSDH in our department. Three neurosurgeons measured and calculated CSDH volumes independent of one another. We investigated potential measurement biases of three neurosurgeons and analyzed the validity of the XYZ/2 technique by comparing it to the gold standard method. The XYZ/2 technique includes the “maximal method” that uses the maximum length and maximum width of a slice to determine volume, and the “central method” that uses only the central slice to measure length and width.

Results

ICCs for the gold standard, central method, and maximal method were 0.945, 0.916, and 0.844, respectively, all of which indicated excellent reliability. For all examiners, the differences in calculation from gold standard and central method were not statistically significant (P > 0.05). The estimations of CSDH volume calculated by the maximal method were significantly greater than the estimates calculated by the gold standard (P < 0.05).

Conclusions

This study proves that the XYZ/2 technique is a simple and reliable method of estimating CSDH volume. The “central method” in particular yielded similar results to that of the gold standard method.

中文翻译：

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估算慢性硬膜下血肿体积的简单方法的有效性

目标

据报道，XYZ/2 技术（使用血肿的长度、宽度和高度）是一种简单可靠的估计慢性硬膜下血肿体积的方法。两种子类型的技术能够进行充分估计，目前尚不清楚哪种更准确。计算机辅助体积分析被广泛认为是 CSDH 体积分析的黄金标准。考虑检查员之间分析的稳定性很重要，因为个体、决策差异可能与分析有关，因为血肿边缘和长度是手动操作的。在这项研究中，我们调查了三位神经外科医生的潜在测量偏差，并通过将其与金标准方法进行比较来分析 XYZ/2 技术的有效性。

方法

我们回顾性分析了我们科 50 名 CSDH 患者需要手术的 CT 扫描结果。三位神经外科医生相互独立地测量和计算 CSDH 体积。我们调查了三位神经外科医生的潜在测量偏差，并通过将其与金标准方法进行比较来分析 XYZ/2 技术的有效性。XYZ/2技术包括使用切片的最大长度和最大宽度来确定体积的“最大法”和仅使用中央切片来测量长度和宽度的“中心法”。

结果

金标准、中心法和最大法的 ICC 分别为 0.945、0.916 和 0.844，所有这些都表明具有极好的可靠性。对所有考官而言，金标准和中心法计算的差异均无统计学意义（P  >  0.05）。最大法计算的CSDH体积估计值显着大于金标准法计算的估计值（P  <  0.05）。

结论

本研究证明 XYZ/2 技术是一种简单可靠的估计 CSDH 体积的方法。特别是“中心方法”产生了与金标准方法相似的结果。