Dural closure is a critical step in most cranial surgeries. However, no unified consensus currently exists regarding the standardization of dural repair procedures. Previous studies indicate that clinicians often prefer to reinforce primary suturing with sealants or dural substitutes to achieve watertight closure, with satisfactory clinical outcomes reported (1–5). The shape of dural incisions varies, commonly including “U-shaped,” “Y-shaped,” and “L-shaped,” influenced by factors such as surgery type and location. The choice of incision type and repair method often depends on the surgeon's experience and preference, compounded by the diversity of repair materials (e.g., sutures, sealants, dural substitutes) (6, 7), which poses challenges to establishing consistent clinical practices. Currently, the comparative clinical benefits of different systematic repair approaches remain inconclusive, and robust research in this area is still limited (8). Achieving watertight dural closure is paramount, and suturing technique is crucial (9). However, intraoperative factors like dehydration, light exposure, and electrocautery can cause dural shrinkage, significantly increasing the difficulty of direct suturing and elevating the risk of CSF leak and other complications (10). This study therefore introduces two distinct repair protocols for the common U-shaped dural incision—direct suturing and fascia-assisted suturing—the choice of which is determined by the intraoperative feasibility of direct dural closure. The aim is to analyze the clinical efficacy of these two approaches in supratentorial and infratentorial surgeries, compare their applicability, provide references for clinical practice, and systematically evaluate their outcomes in different surgical contexts.

Autologous fascia, as a traditional autograft, is widely used due to its advantages of being non-toxic, non-immunogenic, and capable of vascularization (7, 11). Its unique biomechanical properties are also reasons for its popularity (12, 13). Pericranium, a type of autologous fascia, compared to fascia lata, does not require an additional surgical incision, making it an ideal repair material. Current reports on pericranium application predominantly focus on infratentorial and posterior fossa surgeries (5, 14, 15), with relatively fewer reports for other sites. One of the repair methods evaluated in this study utilizes pericranium as an auxiliary material, aiming to compare whether the repair technique incorporating pericranium yields satisfactory results for the same type of U-shaped incision in both supratentorial and infratentorial locations. The second part of this study involves a systematic review of recent literature on the application of autologous fascia in duraplasty, aiming to corroborate our findings and provide an in-depth discussion on the clinical outcomes of pericranium as a traditional dural substitute at different surgical sites.

Data analysis was performed using IBM SPSS Statistics 27 software. Continuous variables are expressed as mean ± standard deviation, and intergroup comparisons were made using Student's t-test; categorical variables are expressed as frequency and percentage, and intergroup comparisons were made using the Chi-square test or Fisher's exact test. Additionally, to adjust for baseline differences, multivariable logistic regression models were constructed for the surgical method and primary/secondary outcomes. Statistical significance was set at P < 0.05.

The origin of modern dural suturing techniques can be traced to the pioneering work of Harvey Cushing (28), who first established fundamental principles for neurosurgical procedures, including the crucial step of suturing the dura and galea at closure, an innovation that significantly reduced mortality in brain surgery and laid the foundation for dural suturing techniques. Advancements in micro-neurosurgical techniques have provided reliable support for dural suturing, and research on biomaterials has offered diverse choices. Currently, they can be broadly divided into two categories: primary closure and dural repair material closure (autologous fascia, artificial dura). In the dural repair process, watertight closure is generally achieved using interrupted, continuous, or locked suturing techniques. It is generally believed that the suturing technique itself usually has no significant impact on the outcome (29, 30),while the choice of suture material does affect the result (31) (32). Autologous materials: Harvested from the patient's own tissues (e.g., pericranium, fascia, muscle), they offer excellent biocompatibility and no risk of immune rejection, but harvesting may increase surgical trauma and time. Artificial materials: Do not require additional harvesting, but carry issues such as foreign body reaction, chronic inflammation, or differences in degradation cycles (3, 6, 17, 19), Based on these considerations, we propose that the use of autologous fascia for repair, when feasible, in conjunction with a short-cycle artificial dura mater overlay, can effectively prevent postoperative CSF leakage. Furthermore, if intracranial infection occurs, since the circulating CSF does not contact artificial foreign materials, inflammation can be effectively controlled within a certain period, avoiding the potential need for secondary surgery to remove foreign bodies. A prospective clinical trial conducted by Velnar et al. (33) found that autologous muscle fibers are effective for repairing small dural defects, while larger defects have a higher probability of CSF leak, requiring meticulous dural repair, and suggesting the combined use of artificial dura, autologous fascia, and other materials—a conclusion consistent with our practice.

CSF leak is the most serious and most studied complication after dural repair. Literature reports the incidence of CSF leak in neurosurgery ranges from 0% to 34% (34, 35). Typically, postoperative subcutaneous fluid collection is one characteristic of CSF leak (36, 37), and postoperative persistent positional headache also suggests its occurrence (38, 39), Management usually involves conservative treatment, with a small proportion of patients requiring secondary repair. In this study, both methods controlled the CSF leak rate at a low level (<8%), consistent with rates reported in the literature (16, 37) after adopting meticulous repair strategies. This result confirms that the two methods proposed in this study are both effective in ensuring the integrity and reliability of dural repair. Whether direct suturing or pericranium-assisted suturing, as long as strict watertight closure principles are followed (including locked suturing, biological glue reinforcement, and artificial dura coverage), the key pathway for CSF leak can be effectively blocked. Notably, our analysis of re-repair rates revealed low and statistically comparable rates between supratentorial and infratentorial sites for both Method 1 (4.76% vs. 0%, P = 0.383) and Method 2 (4.17% vs. 0%, P = 0.692). This finding indicates that, despite the higher infection risk associated with pericranium-assisted suturing in the infratentorial region, the mechanical integrity and reliability of the repair in preventing major CSF leaks necessitating re-operation remained robust, further supporting its utility in managing complex dural defects. Infection after autologous fascia repair is also a frequently discussed topic. One literature summary suggested that homologous fascia materials are the choice with the lowest infection rate (40). Regarding infection, our analysis revealed site-specific differences: Method 2 had a significantly higher infection rate in infratentorial surgeries compared to supratentorial surgeries (23.33% vs. 6.25%, P = 0.039). Importantly, this increase was predominantly attributable to incision infection/delayed healing (16.67% vs. 2.08%, P = 0.028), whereas the rates of meningitis were not significantly different (6.67% vs. 4.17%). This pattern suggests that the pericranium-assisted technique in the posterior fossa may predispose to localized wound complications rather than direct cerebrospinal fluid track-related infections, potentially attributable to the more challenging wound environment, compromised local vascularity, and intricate drainage dynamics characteristic of infratentorial approaches. Although multivariable regression analysis suggested the surgical site itself was not an independent risk factor (fully adjusted OR 2.49, P = 0.210 for overall infection), mechanistic explanations may involve the following: 1. The infratentorial space is narrow, and differences in CSF circulation dynamics (e.g., posterior fossa high pressure) may cause continuous tension at the fascia repair site, affecting healing; whereas supratentorial dural tension is lower, potentially offsetting the mechanical disadvantages of fascia repair (19, 34); 2. particularly in a region with higher microbial exposure and poorer vascular supply. Although autologous fascia is widely believed to have good biocompatibility and low immunogenicity (7, 11), some studies have pointed out that the additional trauma from fascia harvesting and micro-gaps at the suture interface could become risk points for infection (33). 3. Pericranium has a relatively poor blood supply and weaker anti-infection capability compared to fascia lata, potentially making it more susceptible to disadvantages in the high-pressure, complex CSF dynamics environment of the infratentorium. In the supratentorium, the infection risk of fascia implantation might be offset by the lower susceptibility of the surgical site (e.g., easier drainage of dead space supratentorially). This finding underscores the complex influence of surgical site on the selection of repair materials.

Our findings show both consistency and complexity with the literature. On one hand, numerous studies (14, 15, 19) have reported the successful application of autologous fascia (including pericranium and cervical fascia) in posterior fossa surgery, supporting its safety and efficacy. On the other hand, our discovery shares similarities with the study by Tahami et al. (24), which also found no significant difference in complication rates when comparing pericranium and human amniotic membrane, suggesting that material choice is not the sole determinant, and surgical technique, patient baseline status, and local anatomical environment may all influence outcomes. Additionally, Jurlina et al. reported good performance of free temporalis muscle fascia in skull base reconstruction (24), indicating that autologous fascia from different sources may have differences in anti-infection capability and healing potential.

Another important finding of this study is that although Method 2 had a higher infection rate in the infratentorium, its performance in preventing CSF leak was stable, suggesting that pericranium remains an effective sealing material in complex infratentorial surgeries, but its use requires weighing the infection risk. This aligns with the concept proposed by Velnar et al. (33) of “combining multiple materials to address different defects,” and also suggests that future efforts could further optimize the fascia harvesting and handling process, such as combining short-cycle artificial dura coverage, to balance sealing ability and anti-infection capability.

This study has several limitations. First, the inherent selection bias and confounding bias of its retrospective design cannot be completely avoided. Although we adjusted for known confounders using multivariable regression, some unmeasured variables (such as precise tumor size, relationship to venous sinuses, extent of electrocautery use, patient preoperative nutritional and immune status) might still influence the results. Second, the sample size, particularly in the infratentorial-Method 2 subgroup (n = 30), remains insufficient, potentially leading to overestimation or underestimation of the infection risk and affecting the stability of the results. Third, the study focused on “U-shaped” incisions to ensure homogeneity, but this limits the generalizability of conclusions to other incision types (e.g., the common “Y-shaped” incision in the posterior fossa, supratentorial “+” shaped incisions). Finally, the intraoperative judgment of “significant dural shrinkage,” although standardized by the team and provided with quantitative references, still contains subjective components. Despite these limitations, the findings of this study possess clear clinical implications. They suggest that in supratentorial surgeries, both strategies can be safely chosen based on intraoperative conditions. However, in the infratentorium, especially when anticipating complex, prolonged surgery, if planning to use pericranium-assisted suturing, surgeons need to maintain high vigilance for this potential infection risk and should further strengthen aseptic techniques, consider more adequate drainage, and optimize perioperative antibiotic prophylaxis strategies. More importantly, the “Intraoperative Assessment → Repair Strategy Selection” pathway applied in this study provides a clear, executable framework for dural repair. This decision-making model based on objective assessments (such as the PEEP test and degree of shrinkage) helps reduce variability stemming from reliance solely on personal experience. The customized closure process based on incision type proposed by Ma et al. (41) also demonstrates the potential of similar concepts. Future research should focus on prospective, multicenter designs and incorporate more objective dural assessment indicators (such as intraoperative measurement of defect area). Simultaneously, extending the pathway proposed in this study to validate it for other types of dural incisions is an important step towards promoting comprehensive standardization in dural repair practice.

This study confirms that for U-shaped dural incisions, the two strategies, direct suturing and pericranium-assisted suturing, are equally effective in preventing CSF leak. However, pericranium-assisted suturing presents a higher infection risk in infratentorial surgeries, indicating that in clinical decision-making, especially for complex posterior fossa surgeries, its superior sealing capability must be carefully balanced against its associated infection risk. The “Intraoperative Assessment → Repair Strategy Selection” pathway presented herein offers a valuable decision-making framework for dural repair.