Modified Computed Tomography Classification for Chronic Subdural Hematoma Features Good Interrater Agreement: A Single-Center Retrospective Cohort Study
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Published on: November 20, 2015
Jun Takei1, Tatsuya Hirotsu2, Keisuke Hatano2
1Department of Neurosurgery, Fuji City General Hospital, Fuji, Shizuoka, Japan; Department of Neurosurgery, Jikei University School of Medicine, Minato-ku, Tokyo, Japan.
Insights
A new modified Nakaguchi classification for chronic subdural hematoma (CSDH) shows improved interrater agreement and aids in predicting CSDH recurrence. This classification is valuable for preoperative assessment and patient management.
Area of Science:
- Neurosurgery
- Radiology
- Medical Imaging
Background:
- Chronic subdural hematoma (CSDH) classification impacts treatment and recurrence prediction.
- Existing computed tomography (CT) classifications have limitations in interrater agreement.
Purpose of the Study:
- To evaluate if a modified Nakaguchi CT classification improves interrater agreement for CSDH.
- To assess the modified classification's ability to predict CSDH recurrence compared to other methods.
Main Methods:
- Retrospective analysis of 277 CSDH patients and 307 hematomas treated with burr-hole surgery.
- Classification of CT scans using Nomura, Nakaguchi, and modified Nakaguchi systems by blinded neurosurgeons.
- Interrater agreement assessed using κ statistic; recurrence predicted via logistic regression.
Main Results:
- Modified Nakaguchi classification achieved the highest interrater agreement (κ=0.78).
- The gradation type within the modified classification was linked to the highest recurrence rate (15.9%).
- Gradation-type hematoma was identified as an independent risk factor for CSDH recurrence (OR=2.36, P=0.025).
Conclusions:
- The modified Nakaguchi CT classification offers high interrater agreement for CSDH.
- This classification system is effective for preoperative assessment and predicting CSDH recurrence.
Objective:
The present study aimed to establish whether our modified Nakaguchi computed tomography (CT) classification improves the interrater agreement of chronic subdural hematoma (CSDH) classification and prediction of CSDH recurrence relative to 2 other CT classifications.
Methods:
This retrospective study considered 277 consecutive patients with CSDH and 307 hematomas treated with burr-hole surgery between January 2009 and December 2018. Two neurosurgeons blinded to patients' clinical data classified the CT scans of patients with CSDH into 4 or 5 types according to the Nomura classification (high, iso, low, mixed, and layering), Nakaguchi classification (homogenous, laminar, separated, and trabecular), and our modified Nakaguchi classification (homogenous, gradation, laminar, separated, and trabecular). The κ statistic was used to evaluate the interrater agreement of the 3 CT classifications. Univariable and multivariable logistic regression analyses were used to calculate odds ratios for CSDH recurrence.
Results:
κ values of the modified, Nakaguchi, and Nomura classification were 0.78, 0.63, and 0.70, respectively. During the 3 months follow-up, the recurrence rate for CSDH was 11.4% (35/307 hematomas). Of the types defined by the modified classification, the gradation type was associated with the highest recurrence (mean recurrence rate, 15.9% ± 0.3%). Multivariable logistic regression analyses showed that a gradation-type hematoma, as defined with the modified classification, was an independent risk factor associated with recurrence (odds ratio, 2.36; 95% confidence interval, 1.11-4.98; P = 0.025).
Conclusions:
The modified classification was useful for preoperative CT classification of CSDH and the prediction of recurrence, with high agreement between raters.
