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

Differences in neuroradiological impacts of hematoma volume and midline shift on clinical symptoms and recurrence rate in patients with unilateral chronic subdural hematoma

OBJECTIVE

Chronic subdural hematoma (CSDH) is a prevalent neurosurgical condition, particularly among the elderly. Hematoma volume (HV) and midline shift (MLS) on CT imaging are critical for assessing CSDH severity and recurrence risk. Brain atrophy has also been linked to recurrence. This study investigates the impact of HV and MLS on clinical symptoms and recurrence, considering brain atrophy.

METHODS

A retrospective analysis was conducted on patients with unilateral CSDH who underwent burr hole surgery for symptoms such as headache, disturbances of consciousness, hemiparesis, and gait disturbance. HV, MLS, and relative cortical atrophy index (RCAI) were measured using preoperative (pre-) and postoperative (post-) CT images. The rate of change in RCAI (RCAI-CR) between pre- and post-CT images was calculated to assess contralateral brain compression. Associations between HV, MLS, RCAI, RCAI-CR, symptoms, and recurrence were analyzed.

RESULTS

The study included 293 patients (mean age 79.4 ± 12.1 years), with a recurrence rate of 15.0 % (44/293). Pre-HV (per 10 mL) was significantly associated with hemiparesis and gait disturbance (odds ratio [OR] 1.12, 95 % confidence interval [CI] 1.03-1.21, p = 0.011; OR 1.14, 95 % CI 1.05-1.24, p = 0.003). Pre-MLS was significantly correlated with disturbances of consciousness (OR 1.26, 95 % CI 1.14-1.39, p < 0.001) and was elevated in patients with high RCAI-CR. Significant predictors of recurrence included Pre-HV (per 10 mL) (OR 1.16, 95 % CI 1.03-1.31, p = 0.014), postoperative subdural cavity volume (per 10 mL) (OR 1.18, 95 % CI 1.02-1.36, p = 0.026), antiplatelet drug use (OR 0.23, 95 % CI 0.06-0.89, p = 0.032), and CT classification (OR 2.35, 95 % CI 1.15-4.82, p = 0.020).

CONCLUSIONS

HV and MLS have distinct clinical implications in CSDH. Pre-HV is linked to motor disturbances, while Pre-MLS correlates with disturbances of consciousness, with high RCAI-CR indicating significant brain compression. HV is a key predictor of recurrence, while MLS and RCAI are not. These findings may improve outcome prediction and management strategies.

Role of Sulcal Hyperintensity and Web/Net Appearance on MRI in Patients With Chronic Subdural Hematoma Presenting With Transient Neurological Deficits

BACKGROUND AND OBJECTIVES

Transient neurological deficits (TNDs) in patients with chronic subdural hematoma (CSDH), such as fluctuating aphasia, hemiparesis, or sensory disturbances, present diagnostic and treatment challenges as their pathophysiology remains unclear. The aim of this study was to investigate the association between specific MRI findings and TNDs in patients with CSDH and explored their relationship through intraoperative observation.

METHODS

We retrospectively evaluated 72 patients with CSDH who underwent preoperative MRI among 251 CSDH patients treated from January 2020 to December 2023. Sulcal hyperintensity (SHI) on fluid-attenuated inversion recovery images and web/net appearance (W/N) on T2*-weighted images were assessed and their association with TNDs was analyzed. Flexible neuroendoscopic surgery (FNS) was performed on 8 patients with TNDs exhibiting these MRI findings, allowing intraoperative observation of intrahematoma conditions. Histopathological examination was performed on hematoma samples.

RESULTS

Thirteen patients (5.2%) presented with preoperative TNDs. Diffuse SHI and W/N were strongly associated with preoperative TNDs (odds ratio = 150.0, P < .001). FNS revealed organized hematomas with inflammatory changes corresponding to the SHI and W/N seen on MRI. Patients who underwent FNS experienced complete resolution of TNDs postprocedure, with diffuse SHI disappearing by one month. No recurrence was observed at a mean follow-up of 5.9 months.

CONCLUSION

This study provided the first evidence that the combination of diffuse SHI and W/N on MRI strongly correlates with TNDs in patients with CSDH, serving as valuable diagnostic indicators. These findings will aid in guiding surgical approach selection and facilitate more personalized treatment strategies for patients with CSDH presenting with TNDs.

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.

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.

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.