Operative Neurosurgery最新文献

Background and objectives: This work aimed to identify different configurations of the adytum of the cerebral aqueduct suggesting its safe neuroendoscopic navigation. This concept is intimately connected to the physiological aqueductal dilatability or compliance, which is relatively ignored in the literature. A better knowledge of the extent of physiological aqueductal dilatability might better define the ideal diameter and safer features of dedicated flexible endoscopes.

Methods: The study includes 45 patients operated on using a flexible scope with a 3.9-mm diameter, where the structural elements of the adytum of the cerebral aqueduct are clearly visible. Patients were grouped according to the pathology (colloid cyst/normal anatomy, intraventricular hemorrhage, tetraventricular obstructive hydrocephalus, normal pressure hydrocephalus, and distal membranous aqueductal stenosis). A simple geometrical scheme was applied to the endoscopic anatomy of the aqueductal adytum in relation to the posterior commissure to measure its pathologic deformations. Eventual damages to the aqueduct walls caused by the endoscope were also reported.

Results: Proceeding from normal anatomy to hydrocephalic condition, the ratio between the commissure and the aqueductal access area progressively decreases, while the vertex angle increases. Interestingly, the entity of the ependymal damages due to the passage of the endoscope correlates with such measures.

Conclusion: The cerebral aqueduct, excluding atrophic processes, is provided with a certain degree of dilatability, which we estimate to be around a diameter of 4 mm. This represents the maximum size for a flexible neuroendoscope for a safe aqueductal neuronavigation. The schematic model of the aqueductal adytum as a triangle defines 3 different aqueductal patterns and can be helpful when an intraoperative decision on whether to navigate the aqueduct must be taken.

Background and objectives: The coexistence of complete carotico-clinoid bridge (CCB), an ossification between the anterior (ACP) and the middle clinoid (MCP), and an interclinoidal osseous bridge (ICB), between the ACP and the posterior clinoid (PCP), represents an uncommonly reported anatomic variant. If not adequately recognized, osseous bridges may complicate open or endoscopic surgery, along with the pneumatization of the ACP, especially when performing anterior or middle clinoidectomies.

Methods: According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews guidelines, a systematic scoping review was conducted up to June 5, 2023. PubMed, Scopus, Web of Science databases, and additional citations were searched. Two hundred high-resolution noncontrast computed tomography (CT) scans (400 sides) and 41 dry skulls (82 sides) were analyzed to identify the different morphology of sellar bridges, focusing on the coexistence of complete CCF and ICB. Two embalmed latex-injected heads with coexisting CCF and ICB were dissected step-by-step to show the anatomic relationship with the surrounding structures from an endoscopic and microscopic perspective.

Results: A total of 19 articles were included. The review identified a complete CCF and ICB rate ranging from 4.92% to 6.3%. The analysis of 200 CT scans revealed a rate of coexistence in 4% of the cases, all encountered in White women. Two different types of interclinoid bridges were identified based on the degree of bone mineralization. Both endoscopic and macroscopic step-by-step dissections highlighted variability in morphology and consistency of the sellar bridges and the close relationship with the cavernous sinus neurovascular structures.

Conclusion: The coexistence of CCF and ICB is an anatomic variation found in 4% of cases. Preoperative knowledge of the degree of mineralization and its relationship with surrounding structures is essential to performing safe surgery and minimizing cranial nerve and vascular injuries. Preoperative high-resolution CT scans can adequately identify these anatomic variations.

Background and objectives: The trans-sinus transglabellar and bifrontal approaches offer direct access to the anterior cranial fossa. However, these approaches present potential drawbacks. We propose the biportal endoscopic transfrontal sinus (BETS) approach, adapting endoscopic endonasal approach (EEA) techniques for minimally invasive access to the anterior fossa, reducing tissue manipulation, venous sacrifice, and brain retraction.

Methods: Six formalin specimens were used. BETS approach involves 2 incisions over the medial aspect of both eyebrows from the supraorbital notch to the medial end of the eyebrow. A unilateral pedicled pericranial flap is harvested. A craniotomy through the anterior table of the frontal sinus (FS) and a separate craniotomy through the posterior table are performed. Two variants of the approach (preservative vs cranialization) are described for opening and reconstruction of the FS based on the desired pathology to access. Bone flap replacement can be performed with titanium plates and filling of the external table defect with bone cement.

Results: Like in EEA, this approach provides access for endoscope and multiple working instruments to be used simultaneously. The approach allows wide access to the anterior cranial fossa, subfrontal, and interhemispheric corridors, all the way up to the suprachiasmatic corridor and through the lamina terminalis to the third ventricle. BETS provides direct access to the anterior fossa, minimizing the level of frontal lobe retraction and providing potentially less tissue disruption and improved cosmesis. Cerebrospinal fluid fistula risk remains one of the major concerns as the narrow corridor limits achieving a watertight closure which can be mitigated with a pedicled flap. Mucocele risk is minimized with full cranialization or reconstruction of the FS.

Conclusion: The BETS approach is a minimally invasive approach that translates the concepts of EEA to the FS. It allows excellent access to the anterior cranial fossa structures with minimal frontal lobe retraction.

Background and objectives: To describe a novel, practical, reproducible, and effective preoperative marking technique for accurate localization of the spinal level in a series of patients with tumor lesions.

Methods: We retrospectively analyzed patients undergoing minimally invasive (MIS) surgery for spine tumors from 2016 to 2021, in which this marking technique was used. Twenty-one patients, with tumor lesions involving difficult radioscopic visualization (cervicothoracic junction or upper dorsal spine, C6-T8), were included. Tumor lesion level was previously determined with enhanced MRI in all cases. Twenty-four to forty-eight hours before surgery, computed tomography image-guided carbon marking was performed by administration of aqueous suspension of carbon with a 21-gauge needle placed resembling the MIS approach planned trajectory. During surgery, activated carbon marking was followed until reaching the final target on the bone. Next, sequential dilators and an MIS retractor were placed. Then, bone resection and tumor exeresis were performed according to the case.

Results: Average age was 60.6 years (26-76 years). Fifteen (71%) patients were women. In most cases (76%), tumor pathology involved intradural lesions (meningiomas and schwannomas). In all cases, the marking described allowed to accurately guide the MIS approach to tumor site. Neither intraoperative fluoroscopy nor approach enlargement was required in any procedure. Postoperative complications were reported in only 4 patients, none related with the marking.

Conclusion: Computed tomography image-guided activated carbon marking allows to accurately lead MIS approaches in a practical, reproducible, and effective way in cases of tumors localized in regions of the spine of difficult radioscopic visualization.

Background and objectives: Endoscopic endonasal surgery is a well-established surgical approach to the skull base. Surgeons need a reusable long-lasting tool to acquire the skills needed for skull base reconstruction. The aim of this study was to elaborate and validate a human formalin-fixed cadaveric model that reproduces a realistic cerebrospinal fluid (CSF) circulation and that adequately renders a CSF leak.

Methods: An external ventricular drain that connects with a peristaltic pump is placed in the subarachnoid space, which allows a water circulation that reproduces CSF circulation. Intracranial pressure is measured in real time. Endoscopic endonasal skull base approaches are performed, to create different skull base openings and CSF leaks. Participants were tasked with reconstruction of the defects using a standardized multilayered approach, with the goal of obtaining a watertight closure under normal intracranial pressure ranges. Compiled data included time of reconstruction, years of experience of participants, and success/failure to achieve a watertight reconstruction. A Likert questionnaire was also used.

Results: The cadaveric model reproduced CSF circulation in 4 types of dural defects: sellar, suprasellar, transcribriform, and transclival. Intracranial pressures were similar to physiological conditions and were reproducible. Each model was tested multiple times, over several months. Success rates concurred with training levels (r = .8282 and P = .0017). A strong inverse correlation was also found between years of experience and time of reconstruction (r = .4977 and P < .0001). Participants agreed that the model was realistic (median Likert score of 4), and they strongly agreed that it allowed for the improvement of their surgical skills (median Likert score of 5).

Conclusion: This novel human-fixed cadaveric model for CSF circulation is efficient and adequately reproduces surgical conditions for skull base approaches. The model is unique, easy to reproduce, and reusable. It can be used as a tool for teaching and for research purposes.

Background and objectives: Traditional and well-established transcranial approaches to the spheno-orbital region and middle cranial fossa guarantee optimal intracranial exposure, and additional orbital and zygomatic osteotomies provide further control over extracranial components to be resected; however, these techniques come at the cost of additional morbidity. The introduction of minimally invasive endoscopic approaches and the conceptualization of the so-called "multiportal" paradigm might provide an alternative route. This preliminary study investigates the feasibility of the combined Biportal Endoscopic TransOrbital and transMaxillary Approach (bETOMA) approach to the spheno-orbital and middle cranial fossa regions.

Methods: Using 4 silicon-injected adult cadaver heads (8 sides; 16 approaches), we systematically dissected through superior eyelid ETOA and endoscopic TMA approaches. The analysis focused on pterygopalatine, infratemporal, anterior and middle cranial fossae, Meckel cave, and cavernous sinus access. We evaluated the feasibility of bETOMA using linear distances, angles of attack, and exposure areas. We also introduced volume of operative maneuverability, its standardized derivative (sVOM), target distance, visuo-operative angle, and working zone volume as novel metrics.

Results: The analysis revealed comparable angles of attack between approaches. ETOA and TMA exposure areas were 918.38 ± 223.93 mm 2 and 257.07 ± 86.07 mm 2 , respectively. TMA showed a larger VOM in the greater sphenoid wing, but ETOA offered superior distal maneuverability (sVOM: 5.39 ± 1.94 vs 2.54 ± 0.79 cm 3 ) and closer intracranial space access (27.45 vs 50.83 mm). The combined approaches yielded a mean working zone volume of 13.75 ± 3.73 cm 3 in the spheno-orbital interface.

Conclusion: The bETOMA approach provides adequate neurovascular exposure and maneuverability to the spheno-orbital region, infratemporal, and anterior and middle cranial fossae, addressing significant limitations of previously investigated monoportal techniques (ie, optic nerve decompression, hyperostotic bone resection, and infratemporal exposure). This combined minimally invasive approach might help manage lesions harbored within the cranio-orbital interface region invading the extracranial space.

Background and objectives: Minimally invasive endoscopic approaches in cranial base surgery have been developing in the past decades. The transorbital (TO) route is one promising alternative, yet its adequacy for intracranial vascular lesions remains unclear. The present anatomic work aimed to test the feasibility and to provide a qualitative description of the endoscopic TO approach for the anterior circulation, namely the internal carotid artery and the middle cerebral artery.

Methods: Seven embalmed adult cadaveric specimens (12 sides) were used in the study. Each side was approached in 3 successive steps: (1) Superior-eyelid TO approach, with great and lesser sphenoid wing removal. (2) Removal of anterior clinoid process (ACP). (3) Removal of the lateral orbital rim. All the procedures were performed under endoscopic view.

Results: The TO approach without removing the ACP allowed to dissect the sphenoidal and lateral segments of the Sylvian fissure with an adequate identification of the middle cerebral artery bifurcation in all specimens. The removal of the ACP allowed further dissection toward the opticocarotid cistern, with the identification of the ophthalmic, posterior communicating, and the anterior choroidal arteries. The internal carotid artery bifurcation and A1 segment were also readily identified. Finally, removal of the lateral orbital rim provided a wider and more comfortable access to the above-mentioned vascular structures.

Conclusion: According to our anatomic data, the TO approach can be used to reach the main vascular components of the anterior circulation. This opens the field for exploring its application in the treatment of vascular pathology, particularly aneurysms.

Background and objectives: As the radial approach is gaining popularity in neurointervention, new radial-specific catheters are being manufactured while taking into consideration the smaller size of the radial artery, different trajectories of angles into the great vessels from the arm, and subsequent force vectors. We compared outcomes of transradial procedures performed using the Armadillo catheter (Q'Apel Medical Inc.) and the RIST radial guide catheter (Medtronic).

Methods: This is a retrospective multicenter study comparing outcomes of transradial neuroendovascular procedures using the Armadillo and RIST catheters at 2 institutions between 2021 and 2024.

Results: The study comprised 206 patients, 96 of whom underwent procedures using the Armadillo and 110 using the RIST. Age and sex were comparable across cohorts. In most procedures, 1 target vessel was catheterized (Armadillo: 94.8% vs 89.1%, P = .29) with no significant difference between cohorts. The use of an intermediate catheter was minimal in both cohorts (Armadillo 5.2% vs RIST: 2.7%, P = .36), and the median number of major vessel catheterization did not significantly differ between cohorts (Armadillo: 1 [1-4] vs RIST: 1 [0-6], P = .21). Failure to catheterize the target vessel was encountered in 1 case in each cohort (Armadillo: 1.0% vs RIST: 0.9%, P = .18), and the rate did not significantly differ between cohorts. Similarly, the rate of conversion to femoral access was comparable between cohorts (Armadillo: 2.1% vs RIST: 1.8%, P = .55). There was no significant difference in access site complications (Armadillo: 1% vs RIST: 2.8%, P = .55) or neurological complications (Armadillo: 3.1% vs RIST: 5.5%, P = .42) between cohorts.

Conclusion: No significant difference in successful catheterization of target vessels, procedure duration, triaxial system use, complication rates, or the need for transfemoral cross-over was observed between both catheters. Both devices offer high and comparable rates of technical success and low morbidity rates.