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Comparison of Bilateral and Unilateral Chronic Subdural Hematomas: A Retrospective Multi-institutional Cohort Study
Anoop S Chinthala1, Trenton A Line1, Barnabas Obeng-Gyasi2
1Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Insights
Outcomes for surgically treated unilateral and bilateral chronic subdural hematoma (cSDH) are similar. Retreatment rates, readmission, and mortality did not significantly differ between unilateral and bilateral cSDH groups.
Area of Science:
- Neurosurgery
- Public Health
Background:
- Chronic subdural hematoma (cSDH) presents a significant public health challenge in the US.
- cSDH can manifest as unilateral or bilateral fluid collections.
- Surgical intervention is a common treatment for symptomatic cSDH.
Purpose of the Study:
- To compare surgical outcomes between unilateral and bilateral cSDH.
- To identify factors associated with retreatment in surgically treated cSDH patients.
Main Methods:
- Retrospective cohort study involving 731 patients across 4 trauma centers (2009-2021).
- Patients categorized into: unilateral operated cSDH, bilateral operated cSDH, and unilateral operated bilateral cSDH.
- Exclusion of patients who underwent middle meningeal artery embolization.
- Multivariable logistic regression used to analyze retreatment predictors.
Main Results:
- No significant differences in retreatment rates (14% vs 12%), 30-day readmission (30% vs 25%), or 30-day mortality (5.3% vs 8.0%) between bilateral and unilateral operated cSDH.
- Increased postoperative volume was a significant predictor of retreatment (OR 3.24).
- Bilateral cSDH operated on one side showed similar outcomes to unilateral cSDH.
Conclusions:
- Surgical treatment of unilateral and bilateral cSDH yields comparable outcomes regarding retreatment, readmission, and mortality.
- Recurrence rates for bilateral cSDH are similar to unilateral cSDH, despite their exclusion from some clinical trials.
Background And Objectives:
Chronic subdural hematoma (cSDH) is a major public health issue in the United States. cSDH can present as unilateral or bilateral collections. We compared outcomes of surgically treated unilateral and bilateral cSDH and assessed factors contributing to retreatment.
Methods:
We performed a retrospective cohort study through chart review of patients operated for cSDH from 4 level 1 trauma centers, February 2009 to August 2021. Patients were categorized into 3 groups: (1) unilateral, operated cSDH; (2) bilateral, operated cSDH on both sides; and (3) bilateral cSDH, but only one side operated. Patients with middle meningeal artery embolization were excluded. Data on demographics, clinical presentation, radiological findings, and outcomes were collected. A multivariable logistic regression model assessed factors associated with retreatment.
Results:
We analyzed a total of 731 patients: 563 (77%) had unilateral operated cSDH; 132 (18%) had bilateral operated cSDH; and 36 (5%) had bilateral cSDH but were operated only on one side. We found no significant differences in retreatment rates between patients with bilateral, operated cSDH and those with unilateral, operated cSDH (14% vs 12%, P = .40), 30-day readmission (30% vs 25%, P = .20), or 30-day mortality (5.3% vs 8.0%, P = .30). Increased postoperative volume was associated with a higher risk of retreatment (odds ratio 3.24, 95% CI 2.15-5.07, P < .001). Compared with those with unilateral, operated cSDH, patients with bilateral cSDH operated on one side showed no significant difference in retreatment (11% vs 12%, P > .9), 30-day readmission (14% vs 25%, P = .12), or 30-day mortality (5.3% vs 8.0%, P > .9).
Conclusion:
There was no significant difference in retreatment, 30-day readmission, or 30-day mortality between unilateral and bilateral cSDHs treated surgically. Despite exclusion of bilateral cSDH from major recent clinical trials, their rates of recurrence are similar to unilateral cSDH.