Cortical atrophy in chronic subdural hematoma from ultra-structures to physical properties

Single-cell sequencing analysis of chronic subdural hematoma cell subpopulations and their potential therapeutic mechanisms

BACKGROUND

Chronic subdural hematoma (CSDH) is a prevalent form of intracranial haemorrhage encountered in neurosurgical practice, and its incidence has notably risen in recent years. Currently, there is a lack of studies that have comprehensively classified the cells present in hematomas removed during surgery, and their correlation with CSDH recurrence remains elusive. This study aims to analyse the subcellular populations and occupancy levels within peripheral blood.

METHODS

This study analyses the subcellular populations and occupancy levels within peripheral blood and postoperatively removed hematomas by single-cell sequencing and attempts to analyse the effect of different cell occupancies within peripheral blood and intraoperatively removed hematomas on CSDH.

RESULTS

The single-cell sequencing results showed that the cells were classified into 25 clusters by differential gene and UMAP dimensionality reduction clustering analyses and further classified into 17 significant cell populations by cell markers: pDCs, CD8 T cells, CD4 T cells, MigDCs, cDC2s, cDC1s, plasma cells, neutrophils, naive B cells, NK cells, memory B cells, M2 macrophages, CD8 Teffs, CD8 MAIT cells, CD4 Tregs, CD19 B cells, and monocytes. Further research showed that the presence of more cDC2 and M2 macrophages recruited at the focal site in patients with CSDH and the upregulation of the level of T-cell occupancy may be a red flag for further brain damage. ROS, a marker of oxidative stress, was significantly upregulated in cDC2 cells and may mediate the functioning of transcription proteins of inflammatory factors, such as NFκB, which induced T cells' activation. Moreover, cDC2 may regulate M2 macrophage immune infiltration and anti-inflammatory activity by secreting IL1β and binding to M2 macrophage IL1R protein.

CONCLUSION

The detailed classification of cells in the peripheral blood and hematoma site of CSDH patients helps us to understand the mechanism of CSDH generation and the reduction in the probability of recurrence by regulating the ratio of cell subpopulations.

Relative Cortical Atrophy Index as a Strong Predictor of Recurrence After Surgery for Chronic Subdural Hematoma

BACKGROUND AND OBJECTIVES

Chronic subdural hematoma (CSDH) presents significant management challenges in neurosurgical practice, with recurrence being a notable postoperative consideration. This study aimed to evaluate the Relative Cortical Atrophy (RCA) Index as a predictor of recurrence after CSDH surgery.

METHODS

A retrospective analysis was conducted on 98 patients who underwent surgical evacuation for unilateral CSDH. The RCA Index was calculated using pre- and postoperative cranial imaging, correlating it with patient demographics, hematoma characteristics, and recurrence. Inter-rater reliability among measurements by 4 independent physicians was assessed using the intraclass correlation coefficient (ICC). Correlation and regression analyses were performed to identify the correlation of the RCA Index with other factors and their potential predicting power of CSDH recurrence, respectively.

RESULTS

The study population had a mean age of 74.1 (11.9) years, with a 23.5% (23 patients) recurrence rate of CSDH. The ICC analysis showed excellent inter-rater reliability for RCA Index measurements (ICC: 0.998, 95% CI: 0.997-0.998, P < .001). A higher preoperative RCA Index was significantly associated with recurrence (0.215 [0.031] in the recurrent group vs 0.125 [0.034] in the nonrecurrent group, P < .001). The preoperative RCA Index highly correlated with the postoperative RCA Index (Pearson's correlation: 0.918, P < .001), and there was only a small (average: 0.005) but significant increase in the RCA Index of the unaffected hemisphere after surgery (P = .01).The preoperative RCA Index positively correlated with age, preoperative SDH thickness and volume, and recurrence. A RCA Index cutoff value of 0.165 predicted CSDH recurrence with high sensitivity (95.6%) and specificity (93.3%) (area under the curve = 0.97, 95% CI: 0.93-1).

CONCLUSION

The RCA Index is a simple yet robust predictor of CSDH recurrence. Incorporating this measure into the preoperative assessment may enhance surgical planning and postoperative management, potentially reducing recurrence rates.

Clinical Use of Hematoma Volume Based On Automated Segmentation of Chronic Subdural Hematoma Using 3D U-Net

PURPOSE

To propose a method for calculating hematoma volume based on automatic segmentation of chronic subdural hematoma (CSDH) using 3D U‑net and investigate whether it can be used clinically to predict recurrence.

METHODS

Hematoma volumes manually measured from pre- and postoperative computed tomography (CT) images were used as ground truth data to train 3D U‑net in 200 patients (400 CT scans). A total of 215 patients (430 CT scans) were used as test data to output segmentation results from the trained 3D U‑net model. The similarity with the ground truth data was evaluated using Dice scores for pre and postoperative separately. The recurrence prediction accuracy was evaluated by obtaining receiver operating characteristic (ROC) curves for the segmentation results. Using a typical mobile PC, the computation time per case was measured and the average time was calculated.

RESULTS

The median Dice score of the test data were preoperative hematoma volume (Pre-HV): 0.764 and postoperative subdural cavity volume (Post-SCV): 0.741. In ROC analyses assessing recurrence prediction, the area under the curve (AUC) of the manual was 0.755 in Pre-HV, whereas the 3D U‑net was 0.735. In Post-SCV, the manual AUC was 0.779; the 3D U‑net was 0.736. No significant differences were found between manual and 3D U‑net for all results. Using a mobile PC, the average time taken to output the test data results was 30 s per case.

CONCLUSION

The proposed method is a simple, accurate, and clinically applicable; it can contribute to the widespread use of recurrence prediction scoring systems for CSDH.

Middle Meningeal Artery Embolization versus Surgery in Patients with Chronic Subdural Hematoma-No More Fence Sitting?

BACKGROUND

Endovascular treatment of patients with chronic subdural hematoma using middle meningeal artery (MMA) embolization could become an alternative to surgical hematoma evacuation. The aim of the study was to compare methods and identify parameters to help determine the correct treatment modality.

METHODS

We retrospectively reviewed 142 cases conducted internally; 78 were treated surgically and 64 were treated using MMA embolization. We analyzed the treatment failure rate and complications, and using a binary logistic regression model, we identified treatment failure risk factors.

RESULTS

We found a comparable treatment failure rate of 23.1% for the surgery group and 21.9% for the MMA embolization group. However, in the MMA embolization group, 11 cases showed treatment failure due to early neurological worsening with a need for concomitant surgery. We also found a recurrence of hematoma in 15.4% of cases in the surgery group and 6.3% of cases in the MMA embolization group.

CONCLUSION

Both modalities have their advantages; however, correct identification is crucial for treatment success. According to our findings, hematomas with a maximal width of <18 mm, a midline shift of <5 mm, and no acute or subacute (hyperdense) hematoma could be treated with MMA embolization. Hematomas with a maximal width of >18 mm, a midline shift of >5 mm, and no membranous segmentation could have better outcomes after surgical treatment.