Operative Neurosurgery最新文献

Background and objectives: Meningioma with bone involvement presents challenges for complete resection and cranial reconstruction. 68 Ga-dodecanetetreaacetic acid tyrosine-3-octreotide (DOTATATE) positron emission tomography (PET)/computed tomography (CT) has emerged as an excellent modality for localizing invasive meningiomas because of molecular interaction with somatostatin receptor-2. We present a novel technique to design 3-dimensional-printed artificial cranioplasty, using combined fine-slice CT, MRI, and 68 Ga-DOTATATE PET/CT with Individual Patient Solutions (IPS) CaseDesigner® software. This study's objective was to generate proof-of-concept work for a novel artificial cranioplasty protocol that combines customized cranial implant software and DOTATATE PET/CT.

Methods: Three patients with invasive bone meningiomas were retrospectively identified. For each patient, the proposed protocol combines CT, MRI, and 68 Ga-DOTATATE PET/CT imaging to generate a 3-dimensional cranial reconstruction within the Karl Leibinger Surgical (KLS) Martin-IPS CaseDesigner® software. Subsequently, the virtual rendering is used to manufacture a customized polyetheretherketone (PEEK) implant, along with a guiding component, which ensures precise delineation of surgical borders before craniectomy. Finally, cranioplasty with the customized implant is performed using standard techniques.

Results: The described preoperative cranioplasty design protocol was performed for each patient. Tumor invasion was visualized using 68 Ga-DOTATATE PET/CT. Patient 1 presented with a recurrent right frontal meningioma with invasion into anterior skull base. In this case, IPS CaseDesigner® was used to create a mirror image PEEK implant for the left orbit and affected cranium. Patients 2 and 3 had intraosseous meningiomas invading the frontal bone; customized PEEK implants were tailored to the side of the planned craniectomy for both patients and were successfully placed without complication. Postoperatively, all patients remained neurologically intact and were discharged without complications. In all patients, the PEEK implants exhibited appropriate cranial continuity and integrity.

Conclusion: 68 Ga-DOTATATE PET/CT has high sensitivity and specificity for detecting meningiomas during preoperative planning, particularly when the tumor involves bone. IPS CaseDesigner® demonstrates excellent utility for planning and constructing customized cranioplasties tailored to each patient for skull reconstruction.

Background and importance: Rhino-orbital cerebral mucormycosis (ROCM) is an aggressive fungal infection involving the paranasal sinuses, orbit, and intracranial cavity, with a propensity for vascular invasion. This can lead to complications such as internal carotid artery (ICA) thrombosis and occlusion, presenting major neurosurgical challenges. Although surgical debridement and antifungal therapy are the mainstays of treatment, cases with significant neurovascular involvement require specialized intervention. We report a case of ROCM with severe flow-limiting ICA stenosis treated by direct extracranial-intracranial bypass.

Clinical presentation: tA 65-year-old man with diabetes presented with progressive left-sided blindness and facial numbness. Imaging revealed a left orbital mass extending into the paranasal sinuses and intracranially. Empiric antifungal therapy was started. Pathology confirmed Rhizopus species. Despite extensive surgical debridement and antifungal therapy, the patient developed progressive severe cavernous ICA stenosis, leading to watershed territory strokes. To restore cerebral perfusion, protect from distal emboli, and prepare for potential aggressive debridement, a flow-replacing direct (superficial temporal artery-middle cerebral artery (M2)) bypass was performed, and the supraclinoid carotid was trapped. Intraoperative angiography confirmed robust flow through the bypass. The patient was discharged on antifungal therapy and aspirin. At 6-month follow-up, the patient was neurologically intact with an modified Rankin Scale score of 1. Computed tomography angiography and transcranioplasty Doppler ultrasonography confirmed good flow through the bypass.

Conclusion: In addition to antifungal therapy and surgical debridement, superficial temporal artery-middle cerebral artery bypass can be a lifesaving intervention in the management of ROCM with severe cerebrovascular compromise. This case highlights the critical role of cranial bypass in preserving cerebral perfusion in patients with flow-limiting ROCM-associated ICA invasion.

Background and objectives: The greater occipital nerve (GON) and lesser occipital nerve (LON) have gained importance because of conditions such as occipital neuralgia and cervicogenic headaches. To a great depth, their anatomy is essential for performing viable diagnostic and therapeutic procedures such as nerve blocks and decompression procedures. This research involves identifying key anatomic landmarks and the potential compression points of the GON and LON using cadaveric dissections for possible surgical approaches.

Methods: Five fresh, untreated cadavers, 3 male and 2 female, were dissected bilaterally to trace the pathways of the GON and LON. Anatomic measurements were made using ImageJ software, and coordinates were analyzed with K-means clustering for optimal intervention points. These dissections focused on determining in detail the relation of these nerves to surrounding muscular and fascial structures.

Results: The study shows that for GON, there were many points possible for compression, such as where it pierced through the semispinalis and trapezius muscles along the course of the occipital artery. For the LON, however, the potential compression sites were contact points along the course of the occipital artery. After applying K-means clustering, 4 centroids (M1, M2, M3, and M4) were identified. M1 and M3 correspond to the LON, while M2 and M4 correspond to the GON. These centroid locations lie near the nerves' most common compression sites, suggesting they could serve as strategic landmarks for surgical approaches. Cluster quality measures (inertia and silhouette coefficients) showed well-defined clusters.

Conclusion: This study yields anatomic information about the GON and LON anatomy and illustrates key compression points and optimal sites for therapeutic interventions. Within the constraints of sample size, these findings provide preliminary anatomic insights that can guide more precise nerve block and decompression techniques for occipital neuralgia and related headaches.

Background and objectives: Realistic 3-dimensional (3D) anatomical models may enhance three-dimensional comprehension of the complex anatomy of the skull base. Such models may be generated by photogrammetry, a technical algorithm for photorealistic surface scanning. This study presents a 360° visualization of key neuroanatomical landmarks of the central skull base.

Methods: One formaldehyde-fixed head specimen with polymer-injected vessels underwent extensive exocranial and endocranial dissections on the right side after a sagittal cut. Initially, the dissection of the orbital region, cavernous sinus, and paranasal sinuses identified cranial nerves II, III, IV, and VI; their branches; extraocular muscles; and major vessels. Subsequently, the 5 terminal branches of the VII were exposed, along with cranial nerves IX, X, XI, and XII. A retrolabyrinthine approach and neck dissection revealed the entire course of cranial nerve VII, sigmoid sinus, the jugular bulb, and the intracranial and extracranial segments of nerves IX, X, XI, and XII. In addition, the infratemporal fossa, pterygopalatine fossa, and middle ear structures were presented. Finally, the vertebral artery segments (v2-v4) and the internal carotid artery, including the petrosal and cavernous segments, were dissected and documented. The specimen was 3D scanned by photogrammetry 3D, refined with 3D modeling software, and uploaded to virtual reality and web visualization.

Results: Seven photorealistic models were created and virtual reality videos demonstrating the relevant anatomy in an immersive environment. The courses of intracranial nerves and the associated vascular and soft tissue anatomy were systematically captured from both intracranial and exocranial viewpoints, creating an accurate 360° virtual depiction of the pertinent anatomy.

Conclusion: The 3D 360° photogrammetric models developed in this study may allow a better understanding of essential intracranial and extracranial structures of the skull base. These models facilitate customizable views and represent a valuable, freely accessible resource that complements traditional dissections, photographic atlases, and conventional 3D models.