Acta Neurochirurgica最新文献

Purpose

S1 pedicle screws are often associated with loosening and breakage. Conventional iliac screw (CIS) or S2 alar-iliac (S2AI) techniques improve stability but have their own drawbacks. The percutaneous modified iliac screw (PMIS) technique was developed to overcome these issues with a less invasive approach.

Methods

This study is a retrospective case series conducted by a single surgeon. The PMIS technique uses two virtual fluoroscopic reference lines to avoid critical structures and allows percutaneous insertion of the screw into the intra-iliac cancellous corridor. Between 2014 and 2025, ten patients (2 males, 8 females; mean age 59.9 years) underwent sacropelvic fixation using the PMIS approach. Indications included spinal metastasis (n = 8), infection (n = 1), and degeneration (n = 1). Radiographs were used to evaluate instrumentation, complications, and spinopelvic parameters (PI, PT, SS) before surgery and at the final follow-up.

Results

No infection, screw prominence, or screw-related complications were noted. One revision was needed due to progression of a spinal infection unrelated to the PMIS. Radiographic measurements of PI, PT, and SS remained largely unchanged between preoperative and final follow-up.

Conclusion

PMIS provides a safe and minimally invasive option for sacropelvic fixation. It avoids the limitations of CIS and S2AI while reducing soft tissue dissection. Although early results are promising, larger studies are needed to validate the effectiveness and broader clinical use of this method.

Purpose

Assess through a systematic review the probability of spontaneous regression of aneurysms after receiving surgical, endovascular, or radiosurgical treatment of AVMs in patients with AVM-associated aneurysms.

Methods

A systematic literature review was performed in May 2025 using PubMed, Embase, and Scopus. The PRISMA flowchart for evidence screening and selection was used. Eligible studies included patients over 18 years of age with intracranial AVMs and associated FRAs, and reported spontaneous aneurysm regression following AVM treatment. Studies were excluded if they had fewer than 10 patients, non-intracranial lesions, involved only conservative management, or were not published in English or Spanish. Data on demographics, clinical presentation, interventions, and outcomes were extracted. The risk of bias was assessed using the ROBINS-I tool, and the certainty of the evidence was evaluated using the GRADE framework.

Results

Out of 264 screened studies, 10 met the inclusion criteria, involving a total of 428 patients. Most studies were retrospective cohorts with a moderate risk of bias. Patient ages ranged from 31 to 58 years, with hemorrhagic presentation in over 50%. AVMs were mostly Spetzler-Martin grades I–III and supratentorial. Proximal and distal aneurysms were more common than intranidal types. Regression rates of aneurysms ranged from 3 to 23%, with no consistent correlation to AVM complete obliteration rates, aneurysm type, or location. Spontaneous aneurysm regression is rare, with a pooled rate of 11% across studies. Despite moderate heterogeneity, sensitivity analyses confirmed the robustness of results. Funnel plots suggested possible publication bias, indicating the true rate may be even lower. Clinically, regression should be considered exceptional, reinforcing the need for vigilant follow-up and individualized treatment.

Conclusion

Spontaneous aneurysm regression after AVM treatment is a recognized but variable and low-frequency phenomenon, with the highest observed probability being 23%. Further studies are needed to guide treatment strategies in these complex cases.

Background

Transforaminal Endoscopic Lumbar Discectomy (TELD) is increasing in popularity as a minimally invasive technique for treating lumbar disc herniation (LDH). However, TELD presents technical challenges that may result in a flat learning curve. This study analysed the first patients treated by a single senior neurosurgeon transitioning from tubular microdiscectomy, focussing on the initial learning curve for operative time, recurrence, and complications.

Methods

A retrospective study was conducted using data from a consecutive cohort of the first 213 patients operated for LDH by TELD. We collected basic demographic data and recorded all complications, recurrences, and operative time, among other clinical outcome measures. For analytical purposes (trend testing), the learning curve was divided into four quarters of each approx. 50 patients.

Results

The cohort included 101 (47.4%) females and 112 (52.6%) males, with a mean age of 44.2 ± 11.8 years. An initial steep decrease in operative time after 50 cases performed was observed, decreasing by 21.9 ± 27.7 min (p < 0.001), with operative time showing no further change after those initial 50 cases. Residual LDH was seen in 2 (0.9%) patients. Seventeen (8.0%) patients experienced recurrence of LDH. No statistically significant trend in recurrence rate between quarters was observed (p = 0.99). Complications were experienced by 11 (5.2%) patients, without a significant trend (p = 0.50).

Conclusions

This study demonstrates a clear and steep learning curve for TELD, as shown by a significant decrease in operative time that stabilized after approximately 50 cases. This rapid improvement shows growing familiarity with the technically demanding procedure. In our experience, the initial step of the docking process remains the most challenging aspect, largely due to patient-specific variations. Understanding the initial learning curve is essential for training and surgical planning when transitioning to endoscopic techniques.

Cavernous sinus dural arteriovenous fistula (CS-DAVF) is a rare vascular disorder, with clinical manifestations largely determined by venous drainage patterns. Conventional endovascular treatment via the inferior petrosal sinus or superior ophthalmic vein may be unsuccessful when these access routes are occluded. We report a case of an CS-DAVF (Barrow type D) in which two prior endovascular attempts failed, and complete obliteration of the fistula was subsequently achieved through direct puncture of the cavernous sinus under endoscopic endonasal guidance. Postoperatively, the patient experienced complete resolution of pulsatile tinnitus and stabilization of ocular function. This case suggests that the endoscopic endonasal approach may represent a safe and effective alternative for carefully selected indirect CS-DAVF patients when standard endovascular access is not feasible.

Background

Skull base neurosurgery (SBNS) emerged as a specialized branch of microneurosurgery as it addressed the challenges posed by intricate skull base anatomy. Initially developed through close collaboration with otolaryngologists, SBNS expanded in the 1990s and has undergone substantial advancements over the following decades. In this review, we analyze whether SBNS evolved as an organic development within neurosurgery or an external innovation, and we review key historical literature to support of either hypothesis.

Methods

This is a synthetic, narrative historical review. An initial Pubmed review was performed with combination of keywords of “skull base neurosurgery”, “skull base surgery”, “neuroanatomy”, “microsurgical anatomy” and” neurosurgery complications”. Resulting database was restructured based on peer to peer, semi-structured interviews of two senior skull base neurosurgeons, with over 25 skull base neurosurgeons that were active 1970s–1990s. Emerging themes formed the framework for the analysis.

Results

The evolution of SBNS was organic. It could be categorized into four distinct phases: Initially, Early attempts preceding the systematic application of SBNS techniques, subsequently the birth phase coincided with the widespread adoption of microneurosurgery and the establishment of dedicated societies and international meetings. During the popularization phase, advances in microneuroanatomy and novel approaches enhanced outcomes. Finally, the Maturation phase brought refined surgical approaches, the reevaluation of surgical indications, and the integration of stereotactic radiosurgery and endoscopic skull base surgery as well as international collaboration and teaching activities.

Discussion

SBNS emerged within neurosurgery as a means to address challenging skull base pathologies and to enable surgical access through the skull-base. Its development was driven by collaboration with otolaryngology, alongside technological innovations such as the operating microscope, power drills, endoscopy, and stereotactic radiosurgery. These innovations facilitated the creation of novel surgical approaches, which were later refined through advances in neuroanatomical knowledge and improved understanding of pathology. Over time, SBNS were integrated into general neurosurgical practice and training curricula, allowing wide implementation and continued evolution in many directions.

Purpose

Contusion expansion is a key determinant of outcome after traumatic brain injury (TBI). Because many patients develop acute coagulopathy, it has been proposed that hemostatic changes may drive this expansion, but the link remains uncertain.

Methods

In this retrospective single-center cohort, we included adults with isolated moderate-to-severe TBI and no pre-injury antithrombotic therapy. The hemostatic markers activated partial thromboplastin time (APTT), prothrombin time (PT, reported as INR), platelet count (PLT), and fibrinogen were measured on admission and during the first 72 h. Contusion volumes were derived from serial CT scans. Associations between hemostatic markers and contusion volumes over time were analyzed using generalized additive mixed models (GAMMs), adjusting for confounders.

Results

Among 109 patients, median admission values were fibrinogen 2.4 g/L, PT-INR 1.0, APTT 29 s, and PLT 233 × 10⁹/L. After admission, fibrinogen and PLT declined, whereas PT-INR and APTT increased modestly. Contusion volume increased from a median of 0.7 ml at baseline to 4.6 ml on the third CT. In univariable models, higher APTT and PT-INR values and lower platelet counts were associated with larger contusion volumes, but these associations lost significance after adjustment for age and time from injury.

Conclusion

Hemostatic disturbances, as measured by standard coagulation assays, were common after TBI but not independently associated with contusion volume over time.

Background

Cranioplasty restores cranial integrity following decompressive craniectomy or skull trauma. Despite its reconstructive benefits, post-cranioplasty complication rates are high. Post-operative drainage has been proposed to mitigate these risks, yet its effectiveness remains uncertain. This study evaluates the impact of post-cranioplasty drain insertion on surgical outcomes.

Methods

A systematic literature search of MEDLINE, Embase, and Cochrane CENTRAL Library was conducted in accordance with PRISMA guidelines (PROSPEROID:CRD420251030365). Studies reporting cranioplasty outcomes with post-operative drainage were selected. Primary outcomes were complication rates, including infection, haemorrhage, and cerebrospinal fluid (CSF) leak.

Results

Four studies met the inclusion criteria, comprising 522 patients (mean age 43.7 years) who underwent cranioplasty—282 with post-operative drainage and 240 without. Following decompressive craniectomy, the most common indications for cranioplasty were traumatic brain injury (196/514, 38.1%), vascular causes (187/514, 36.4%), and infection (25/514, 4.9%). All studies reported subgaleal drain use, with one study (25%) using epidural drains in an unspecified number of patients. The overall post-operative complication rate was 75/522 (14.4%), occurring in 23/282 drained patients (8.2%) and 52/240 (21.7%) undrained patients. A meta-analysis comparing post-operative complication rates across all studies between patients with and without post-cranioplasty drainage yielded a pooled risk ratio (RR) of 0.51 (95% CI: 0.21–1.24, p = 0.095).

Conclusions

The results suggest post-cranioplasty drainage does not significantly alter complication rates. However, heterogeneity in drainage protocols limits attribution of outcomes to specific modalities. Going forward, moderated prospective trials are needed to establish standardised post-cranioplasty drainage protocols.

Objective

To introduce acellular dermal matrix (ADM) suturing as a novel repair method for intraoperative high-flow cerebrospinal fluid (CSF) leakage during transsphenoidal surgery (TSA), aiming to replace autologous fat/fascia lata grafts and reduce surgical morbidity.

Methods

Five patients (2 invasive pituitary adenomas, 2 craniopharyngiomas, 1 epidermoid cyst) underwent total sellar/suprasellar tumor resection and presented intraoperative high-flow CSF leakage. ADM grafts were tailored to dural defects and sutured directly to native dural edges. Outcomes included repair integrity, operative efficiency, and postoperative complications (CSF leakage, infection).

Results

All cases achieved dural closure without autologous tissue harvesting. Mean operative time was reduced by avoiding graft harvest procedures. No postoperative CSF leakage or intracranial infections occurred. At 30-day follow-up, all patients exhibited satisfactory recovery with stable skull base reconstruction.

Conclusion

ADM suture repair eliminates donor-site morbidity and shortens operative time while providing robust dural sealing. This technique may be a promising alternative to conventional autologous grafts for high-flow CSF leakage management, warranting larger-scale validation.