CT-Based Quantitative Analysis for Pathological Features Associated With Postoperative Recurrence and Potential Application Upon Artificial Intelligence: A Narrative Review With a Focus on Chronic Subdural Hematomas.

Chronic subdural hematomas (CSDHs) frequently affect the elderly population. The postoperative recurrence rate of CSDHs is high, ranging from 3% to 20%. Both qualitative and quantitative analyses have been explored to investigate the mechanisms underlying postoperative recurrence. We surveyed the pathophysiology of CSDHs and analyzed the relative factors influencing postoperative recurrence. Here, we summarize various qualitative methods documented in the literature and present our unique computer-assisted quantitative method, published previously, to assess postoperative recurrence. Imaging features of CSDHs, based on qualitative analysis related to postoperative high recurrence rate, such as abundant vascularity, neomembrane formation, and patent subdural space, could be clearly observed using the proposed quantitative analysis methods in terms of mean hematoma density, brain re-expansion rate, hematoma volume, average distance of subdural space, and brain shifting. Finally, artificial intelligence (AI) device types and applications in current health care are briefly outlined. We conclude that the potential applications of AI techniques can be integrated to the proposed quantitative analysis method to accomplish speedy execution and accurate prediction for postoperative outcomes in the management of CSDHs.

Clinical Features of Patients With Spontaneous Intracranial Hypotension Complicated With Bilateral Subdural Fluid Collections.

BACKGROUND: Subdural hygromas are often found bilaterally in spontaneous intracranial hypotension (SIH). They frequently progress to chronic subdural hematomas (CSDHs), and if the hematomas are formed, it is difficult to consider SIH as an underlying cause. Whether SIH is underlying or not among the patients presenting bilateral subdural fluid collections (hygromas or CSDHs) is clinically important because the treatment strategy should be different between them. OBJECTIVES: We designed a retrospective case-control study to figure out differential clinical features of the patients presenting bilateral symptomatic subdural fluid collections owing to SIH. METHODS: Sixty-two patients with bilateral symptomatic subdural fluid collections were enrolled, and their data on general demographics, clinical courses, radiological findings, treatments, and outcomes were collected. The patients were divided into "SIH" and "Non-SIH" groups, and a simple logistic regression analysis was performed to clarify the differences between the groups. The consequent receiver operating characteristics (ROC) curve analyses were performed with the significant predictors. RESULTS: Eight patients (13%) were diagnosed with SIH. Young age (odds ratio [OR] = 0.831, 95% confidence interval [CI]: 0.743-0.929, P = .0012), no underlying disease (OR = 0.062, 95% CI: 0.007-0.544, P = .0121), radiological features of brain sagging (OR = 10.36, 95% CI: 0.912-93.411, P = .0017), pseudo-subarachnoid hemorrhage (OR = 15.6, 95% CI: 2.088-116.52, P = .0074), and small amount of fluid collections (OR = 0.719, 95% CI: 0.579-0.893, P = .0029) were significantly associated with SIH group. ROC curve analyses were performed in parameters of age and amount of fluid collection and the cut-off values for each parameter were ≤55 years old and ≤22.08 mm, respectively. Patients diagnosed with SIH underwent epidural blood patches and showed good results, except 1 patient who underwent burr-hole trephinations. CONCLUSION: Bilateral subdural fluid collections due to underlying SIH is associated with young age (≤55 years old), no underlying diseases, smaller amount of fluid collections (≤22.08 mm of depth), and radiological findings of brain sagging or pseudo-subarachnoid hemorrhages.

Quantitative assessment of brain shifting in the late phase postevacuation in unilateral and bilateral chronic subdural hematomas.

AIM OF THE STUDY: Recurrence is more common in bilateral chronic subdural hematomas (CSDHs) than in unilateral. Our aim was to quantitatively compare the late phase of brain shifting postevacuation in unilateral and bilateral CSDHs. MATERIALS AND METHODS: We reviewed computed tomography (CT) scans and medical records of consecutive patients with CSDHs who underwent burr hole drainage. CT scan images (preoperative and postoperative days [PODs] 30 and 60) were imported to Adobe Photoshop, and temporal and spatial changes in brain shifting between PODs 30 and 60, and also the subdural space on POD 60, were analyzed. RESULTS: The bilateral group exhibited a significantly greater late phase of brain shifting than the unilateral group between PODs 30 and 60 (P < 0.001). The median late phase of brain shifting of the bilateral group was 8.9 mm (interquartile range [IQR]: 8.3-9.0 mm) between PODs 30 and 60, while that of the unilateral group was 1.8 mm (IQR: 1.3-2.5 mm). CONCLUSIONS: The postevacuation late phase of brain shifting is statistically greater in bilateral CSDHs than in unilateral CSDHs, which might facilitate bridging vein tearing and consequent rebleeding. This may be one factor accounting for the higher recurrence rate of bilateral CSDHs.

Enlargement of the Middle Meningeal Artery may be an Initiating Factor of Chronic Subdural Hematoma: Three Rase reports and a Literature Review.

Middle Meningeal Artery (MMA) embolization for the treatment of refractory Chronic Subdural Hematoma (CSDH) was first described by Mandai et al. in 2000. Since then, more surgeons have begun to pay attention to such surgery to treat CSDH and explore the changes in the middle meningeal artery in the formation of hematomas. We have presented three cases of chronic subdural hematoma after head trauma and compared the diameter of the middle meningeal artery in MRA images before and after chronic subdural hematoma to discuss our new understanding of CSDH.

Middle meningeal artery embolisation: The review of a new treatment for chronic subdural hematomas.

Background: This is a literature review aiming to provide an update about the recent findings related to the efficacy of middle meningeal artery embolization (MMAE) in the treatment of chronic subdural hematomas (cSDHs), comparison with conventional therapy and deduction of the current recommendations and indications. Methods: The literature is reviewed using a search through the PubMed index using keywords. Studies are then screened, skimmed, and thoroughly read. 32 studies fulfilled the inclusion criteria and are included in the study. Results: Five indications for the application of MMA embolization (MMAE) are deducted from the literature. The usage as a preventive measure after surgical treatment of symptomatic cSDHs in patients with a high risk of recurrence and the usage as a standalone procedure has been the most common reasons for indication of this procedure. Rates of failures for the aforementioned indications have been 6.8% and 3.8%, respectively. Conclusion: The safety of MMAE as a procedure is regarded as a general theme in the literature and can be considered for future applications. Usage of this procedure in clinical trials with more patient segregation and timeframe assessment relative to surgical intervention are recommendations of this literature review.

Surgical Treatment of Chronic Subdural Hematomas in Nonagenarians: Who to Treat?

OBJECTIVE: Although chronic subdural hematomas (cSDH) are often treated surgically it remains plausible that invasive treatment in elderly patients may have a negative effect on survival. The aim of this study was to characterize survival following neurosurgical intervention for cSDH in a selected cohort aged >90 years and to identify prognostic factors that may inform clinical decision-making. METHODS: In total, we identified a cohort of 548 consecutive patients who had undergone burr hole drainage for cSDH in a 5-year period between 2009-2013. Of these patients, 41 were aged >90 years. For each patient, information was gathered from local hospital records, general practice records, and the patients directly. Long-term survival was compared with actuarial data obtained from the National Life Tables. RESULTS: Overall mortality at the time of discharge was 2%. Mortality was 26.8% at 6 months, 36.8% at 1 year, and 47.9% at 2 years. Interestingly, there was no significant difference between the actuarial curve and the survival curve following surgery (hazard ratio, 1.17; confidence interval, 0.67-2.05; P = 0.57). Despite initially departing from the actuarial curve, the survival curve becomes parallel at approximately 1 year. Multivariate analysis showed that preadmission residence and the number of comorbid conditions were significant predictors of survival. CONCLUSIONS: We advocate that neurosurgical intervention for cSDH in selected nonagenarians can be a safe and beneficial procedure. Patients living independently at home and with a limited past medical history were most likely to benefit from the surgery.

Surgical Treatments for Chronic Subdural Hematomas: A Comprehensive Systematic Review.

BACKGROUND: Chronic subdural hematomas (CSDHs) are common neurosurgical conditions among elderly patients. OBJECTIVE: To perform a detailed critical appraisal of all randomized controlled trials (RCTs) of surgical treatments for chronic subdural hematomas and to quantify their intervention effects. METHODS: We performed a broad search for all RCTs with no language or date restrictions, asked the authors for missing data, and applied the Cochrane methods. RESULTS: A total of 24 RCTs involved 1900 patients and 15 comparisons. All outcomes of practical interest were analyzed. Postoperative drainage after burr-hole evacuation reduced the rate of recurrence (risk ratio 0.48, 95% confidence interval 0.34-0.66, P < 0.00001) with no other clear benefits or complications. CONCLUSIONS: This comprehensive, best evidence-based, quantitative, systematic review indicates that the use of a closed system drainage after burr-hole evacuation reduces the rate of recurrences but has no other significant differences. The findings also suggest that: (1) treatment with twist drills is equivalent to that with burr holes; (2) the postoperative bed header in the elevated position might reduce the length of hospital stay; (3) irrigation of the subdural space with thrombin solution in patients with high risk of recurrence might reduce this risk; and (4) treatment with twist drill followed by a closed system drainage during 48 hours, instead of 96 hours, might reduce general complication rates. Most of the trials suffered from unclear or high risks of bias and many involved small samples, precluding strong and definitive conclusions.