Rigid Neuroendoscopy Assisted Hematoma Resection Reduces the Recurrence Rate of Chronic Subdural Hematoma With Mixed Density: A Retrospective Analytic Cohort Study

Endoscopic Management of Chronic Subdural Hematoma Using a Novel Brain Retractor

BACKGROUND

Endoscopic procedures are useful in chronic subdural hematoma especially when there are septations, solid/organized hematoma, and the presence of bridging or neovessels in the cavity. Visualizing the distal hematoma cavity by a rigid scope is challenging in large and curved ones due to the hindrance by the brain surface. Combining rigid endoscopy and brain retractor can overcome this limitation.

METHODS

A retrospective study of 248 patients managed by endoscopic technique was performed and the relevant literature was reviewed.

RESULTS

The brain retractor was used in all patients. Average operative time, subgaleal drainage duration, and hospital stay were 56 minutes, 3.1 days, and 4.6 days, respectively. The average preoperative Glasgow coma scale (GCS) score was 12, which improved to 14 and 15 in 223 and 23 patients, respectively at discharge. There were solid clots, septations, bridging vessels, curved hematoma cavities, rapid expansion of the brain after partial hematoma removal, and recurrences in 59, 52, 15, 49, 19, and 2 patients, respectively. There were 2 deaths, without any procedure-related mortality.

CONCLUSIONS

Endoscope was very effective and safe in the management of chronic subdural hematoma, especially in about 51% patients with solid clots, septations, and bridging vessels which could have been difficult to treat by conventional burr hole. It can avoid craniotomy in such patients. Good visualization and complete hematoma removal were possible with the help of an endoscope and brain retractor in about 27% of patients which could have been difficult with a rigid endoscope alone.

Efficacy analysis of neuroendoscopy-assisted burr-hole evacuation for chronic subdural hematoma: a systematic review and meta-analysis

The purpose of this study was to compare neuroendoscopy-assisted burr-hole evacuation with conventional burr-hole evacuation in the treatment of chronic subdural hematoma (CSDH), and to evaluate the curative effect of neuroendoscopy. This study follows PRISMA guidelines and uses the keywords "chronic subdural hematoma," "neuroendoscopies," "neuroendoscopy," "endoscopy," "endoscopic neurosurgery," and "neuroendoscopic surgery" to conduct an electronic search of online databases, including PubMed, Embase, Web of Science, and Cochrane Library. There were no restrictions on language or publication year. This meta-analysis involved 948 patients in six studies. The results showed that the recurrence rate in the neuroendoscopy group was significantly lower than that in the conventional burr-hole group (3.1% vs. 13.8%, P<0.001). Compared with the control group, the neuroendoscopy group had a longer operation time (P<0.001) and a shorter postoperative drainage time (P<0.001). In addition, there was no significant difference in hospital stay (P=0.14), mortality (P=0.39), postoperative morbidity (P=0.12), or 6-month neurological outcomes (P=0.32) between the two groups. It should be noted that the comparison of neurological outcomes was based on 269 patients (6/106 vs. 14/163). Compared with conventional burr-hole evacuation, neuroendoscopy-assisted burr-hole evacuation reduces the recurrence rate of CSDH and shortens the postoperative drainage time. However, the neuroendoscopy group did not have lower mortality or morbidity or better functional outcomes. In the future, randomized controlled trials are needed to further evaluate the efficacy and safety of neuroendoscopic surgery.

Subdural Lesions Linking Additional Intracranial Spaces and Chronic Subdural Hematomas: A Narrative Review with Mutual Correlation and Possible Mechanisms behind High Recurrence

The purpose of this study was two-fold. The first was to investigate the pathologic mechanisms underlying the formation of subdural fluid collection, an umbrella term referring to a condition commonly seen in the clinical setting. Accumulation of the cerebrospinal fluid (CSF) in the subdural space can be referred to in this disease category, disregarding the underlying source of the subdural fluid. However, in these two clinical situations, especially after trauma or brain surgery, fluid collection from the subarachnoid space (subdural hygroma) or from the ventricle to the subarachnoid space and infusion into the subdural space (external hydrocephalus), surgical management of critical patients may adopt the strategies of burr-hole, subduroperitoneal shunt, or ventriculoperitoneal shunt, which present distinctly different thoughts. Crucially, the former can be further transformed into chronic subdural hematoma (CSDH). The second significant theme was the pathogenesis of CSDH. Once the potential dural border cell (DBC) layer is separated such as if a wound is formed, the physiological mechanisms that seem to promote wound healing will resume in the subdural space as follows: coagulation, inflammation, fibroblast proliferation, neovascularization, and fibrinolysis. These aptly correspond to several key characteristics of CSDH formation such as the presence of both coagulation and fibrinolysis signals within the clot, neomembrane formation, angiogenesis, and recurrent bleeding, which contribute to CSDH failing to coagulate and absorb easily. Such a complexity of genesis and the possibility of arising from multiple pathological patterns provide a reasonable explanation for the high recurrence rate, even after surgery. Among the various complex and clinically challenging subdural lesions, namely, CSDH (confined to the subdural space alone), subdural hygroma (linked in two spaces), and external hydrocephalus (linked in three spaces), the ability to fully understand the different pathological mechanisms of each, differentiate them clinically, and devote more interventional strategies (including anti-inflammatory, anti-angiogenic, and anti-fibrinolysis) will be important themes in the future.

Recurrence of chronic subdural hematoma due to low-grade infection

Despite the high incidence and multitudes of operative techniques, the risk factors for chronic subdural hematoma (CSDH) recurrence are still under debate and a universal consensus on the pathophysiology is lacking. We hypothesized that clinically inapparent, a low-grade infection could be responsible for CSDH recurrence. This investigation is a single-center prospective observational study including patients with recurrent CSDH. In total, 44 patients with CSDH recurrence received an intraoperative swab-based microbiological test. The intraoperative swab revealed an inapparent low-grade hematoma infection in 29% of the recurrent CSDH cases. The majority (69%) of the identified germs belonged to the staphylococcus genus. We therefore, propose a novel potential pathophysiology for CSDH recurrence.