Citations

Spinal sarcomas are rare, aggressive tumors requiring wide resection that creates large, challenging defects. Conventional reconstruction using allografts or metallic implants is prone to failure in compromised settings like irradiated or infected tissue. This narrative review synthesizes the literature on biologic reconstruction strategies, focusing on vascularized bone grafts (VBGs) and the ‘spinoplastic’ reconstruction approach, to provide a clinical framework for their application. We performed a narrative literature review using PubMed and Scopus to synthesize clinical studies describing biologic spinal reconstruction in compromised host beds. The main findings show that pedicled VBGs (e.g., rib, iliac crest) and free VBGs (e.g., fibula) function as living structural components. ‘Spinoplastic’ reconstruction leverages these grafts to promote biologic fusion, with clinical series reporting high union rates, even in irradiated or revision settings, offering a durable alternative to avascular constructs. Biologic reconstruction using VBGs is a critical strategy for achieving durable spinal stability in these challenging scenarios, and future directions point toward hybrid strategies combining 3D-printed implants with the biologic power of VBGs.

BACKGROUND AND OBJECTIVES: Aneurysm risk prediction remains an imprecise science that places patients at risk for either over or undertreatment. Machine learning (ML) models may improve clinical practice by adding precision to risk assessment. This study aims to comprehensively assess the current landscape of ML applications in predicting the risk of aneurysm rupture and compare the performance with the widely used PHASES score. METHODS: A systematic review of PubMed, Scopus, and Web of Science was conducted. All studies using ML tools to predict the rupture risk of intracranial aneurysms were included. Meta-analysis was conducted with consideration to the ML algorithms and compared with the PHASES score. RESULTS: Thirty-six studies involving 22 462 patients were included in the final analysis. ML techniques, including 124 models using 25 algorithms, were employed. Among various ML models, while they had comparable diagnostic performance, deep learning exhibited a slightly better performance profile (sensitivity = 0.792, specificity = 0.788, and accuracy = 0.778 in external validation). Based on our analysis, ML, regardless of the algorithm, provides comparable sensitivity (0.743 vs 0.771, P = .60) and higher specificity (0.763 vs 0.507, P < .01) compared with the PHASES score. Consistently, pooling the area under the receiver operating characteristic curve (AUC) for 60 ML models and 5 PHASES score data, ML models exhibited higher AUC (0.84 vs 0.64, P < .01). Using hemodynamic parameters as input for models improved specificity ( P < .01) in the test sets without any significant changes in the sensitivity. The later improvement was not observed in the external validation sets. CONCLUSION: ML techniques have the potential to enhance the prediction of intracranial aneurysm rupture compared with traditional approaches, like the PHASES score. Incorporating hemodynamic parameters may further enhance the accuracy of ML models. Feature prospective studies are required to validate the utility of ML models for clinical integration.

Summary: Sacral reconstruction post tumor resection has historically been executed with the placement of hardware or free tissue transfer. Reconstruction using a vascularized bone graft is an alternative that avoids the complications associated with hardware placement or free tissue transfer. This article describes the first documented case of spinoplastic reconstruction using an iliac crest vascularized bone graft (IC-VBG) after the resection of a sacral ependymoma. This is a case of a 17-year-old boy with a history of a sacral myxopapillary ependymoma. He presented to a local emergency department complaining of 6 months of urinary incontinence and progressive paresthesias affecting the left lower extremity. Magnetic resonance imaging was significant for a lesion located in the extradural spinal canal. Biopsy confirmed a myxopapillary ependymoma, World Health Organization grade II. The initial intervention involved tumor resection with titanium hardware placement. He subsequently required replacement of the titanium hardware with carbon fiber, secondary to the need for surveillance imaging. He underwent harvesting and inset of the IC-VBG at the time of hardware replacement. IC-VBG is a safe and effective modality for spinoplastic reconstruction. It enhances the potential for solid bony union and offers a practical alternative to free bone transfer. This approach provides an asset to add to a reconstructive surgeon’s armamentarium, making it an essential tool for reconstructive surgeons working in conjunction with spinal surgery colleagues.

BACKGROUND AND OBJECTIVES: Access to the amygdala and hippocampus (A/H) is complex. To address the limitations and invasiveness of traditional approaches, including the Transsylvian, Subtemporal, and Supracerebellar infratentorial approaches, we developed the suprapetrous infratemporal (SPIT) approach. This study describes the nuances of this approach in both cadaveric studies and clinical cases. METHODS: Three unilateral exposures were performed using microscopic and endoscopic methodologies in the SPIT approach. After cadaveric investigation, this approach was successfully implemented in representative clinical cases. RESULTS: The SPIT approach enabled direct access to the inferior A/H, circumventing the requirement for temporal lobe retraction and detachment of the temporal lobe from the dura through a subtemporal route by drilling the upper part of the mastoid, consequently mitigating tension on the vein of Labbé. This enabled a bottom-up view because one would gain with a zygomatic osteotomy and forward projection like a mini-posterior petrosal view by using a transmastoid view, without cutting down the zygomatic arch and opening the dura subtemporally, limiting patient pain and preventing case comorbidity. The SPIT approach was performed in 2 cases of mesial temporal cavernoma presenting with seizures. The lesion was visualized intraoperatively and was successfully removed in these cases. The postoperative course was excellent with no complications, and gross total resection was radiographically confirmed with Engel Class 1a seizure freedom. CONCLUSION: The SPIT approach is a complementary approach for inferior A/H disease, combining the combined middle fossa approach modified for intradural pathology. Limited drilling of the upper aspect of the mastoid with a medial dural opening at the level of the arcuate eminence provides a direct trajectory with minimal brain retraction. Additional research encompassing a larger patient cohort and extended follow-up periods is required to substantiate the advantages of SPIT in the management of inferior A/H lesions.

Background: The transorbital approaches (TOAs) have acquired growing notoriety, thanks to their ability to offer alternative corridors to the skull base. However, the limited access and the unfamiliarity with this surgical perspective make recognition of key landmarks difficult, especially for less experienced surgeons. The study wants to offer a detailed description of the anatomy to comprehend the potential and limitations of TOAs. Methods: Measurements of the orbit region and the surrounding areas were performed on two hundred high-resolution CT scans and thirty-nine dry skulls. Five specimens were dissected to illustrate the TOA, and one was used to perform the extradural clinoidectomy. Three clinical cases highlighted the surgical applications. Results: A step-by-step description of the key steps of the TOA was proposed and a comparison with the transcranial anterior clinoidectomy was discussed. The mean work distance was 6.1 ± 0.4 cm, and the lateral working angle increased 20 ± 5.4° after removing the lateral orbital rim. Conclusions: TOAs are indicated in selected cases when tumor involves the lateral portion of the cavernous sinus or the middle skull base, obtaining a direct decompression of the optic nerve and avoiding excessive manipulation of the neurovascular structures. Comprehension of surgical anatomy of the orbit and its surrounding structures is essential to safely perform these approaches.