The Use of Intraoperative Microvascular Doppler in Vascular Neurosurgery: Rationale and Results-A Systematic Review

Surgical treatment of neurovascular lesions like intracranial aneurysms, arteriovenous malformations and arteriovenous dural fistulas is still associated with high morbidity. Several recent studies are providing increasing insights into reliable tools to improve surgery and reduce complications. Inadvertent vessel compromise and incomplete occlusion of the lesion represent the most possible complications in neurovascular surgery. It is clear that direct visual examination alone does not allow to identify all instances of vessel compromise. Various modalities, including angiography, microvascular Doppler and neurophysiological studies, have been utilized for hemodynamics of flow vessels in proper clipping of the aneurysm or complete obliteration of the lesion. We intended to review the current knowledge about the intraoperative microvascular Doppler (iMDS) employment in the most updated literature, and explore the most recent implications not only in intracranial aneurysms but also in neurovascular lesions like arteriovenous malformations (AVMs) and arteriovenous dural fistulas (AVDFs). According to the PRISMA guidelines, systematic research in the most updated platform was performed in order to provide a complete overview about iMDS employment in neurovascular surgery. Twelve articles were included in the present paper and analyzed according to specific research areas. iMDS employment could represent a crucial tool to improve surgery in neurovascular lesions. The safety and effectiveness of the surgical treatment of neurovascular lesions like intracranial aneurysm and other neurovascular lesions like AVMs and AVDFs requires careful and accurate consideration regarding the assessment of anatomy and blood flow. Prognosis may depend on suboptimal or incomplete exclusion of the lesion.

The role of extended reality in eloquent area lesions: a systematic review

OBJECTIVE

The surgical approach to lesions near eloquent areas continues to represent a challenge for neurosurgeons, despite all of the sophisticated tools currently used. The goal of surgery in eloquent areas is to maintain a good oncofunctional balance, that is, to preserve neurological function and ensure maximum tumor resection. Among all the available tools, extended reality (used to describe both virtual reality [VR] and mixed reality) is rapidly gaining a pivotal role in such delicate lesions, especially in preoperative planning, and recently, even during the surgical procedure. VR creates a completely new world in which only digital components are present. Augmented reality (AR), using software and hardware to introduce digital elements into the real-world environment, enhances the human experience. In addition, mixed reality, a more recent technique, combines VR and AR by projecting virtual objects into the real world, allowing the user to interact with them.

METHODS

A systematic literature review of the last 23.5 years was conducted (January 2000-June 2023) to investigate and discuss all progress related to the emerging role and use of these new technologies (VR, AR, and mixed reality), particularly in eloquent area lesions as a pre- and/or intraoperative tool.

RESULTS

Five hundred eighty-four published studies were identified. After removing duplicates and excluding articles that did not meet the inclusion criteria, 21 papers were included in the systematic review. The use of AR or VR was fully analyzed, considering their roles both intraoperatively and for surgical planning.

CONCLUSIONS

The increasing use of such innovative technologies has completely changed the way to approach a lesion, using 3D visualization to foster a better understanding of its anatomical and vascular characteristics.

The Role of Augmented Reality Neuronavigation in Transsphenoidal Surgery: A Systematic Review

In the field of minimally invasive neurosurgery, microscopic transsphenoidal surgery (MTS) and endoscopic transsphenoidal surgery (ETS) have been widely accepted as a safe approach for pituitary lesions and, more recently, their indications have been extended to lesions at various skull base regions. It is mandatory during transsphenoidal surgery (TS) to identify key anatomical landmarks in the sphenoid sinus and distinguish them from the lesion. Over the years, many intraoperative tools have been introduced to improve the neuronavigation systems aiming to achieve safer and more accurate neurosurgical interventions. However, traditional neuronavigation systems may lose the accuracy of real-time location due to the discrepancy between the actual surgical field and the preoperative 2D images. To deal with this, augmented reality (AR)-a new sophisticated 3D technology that superimposes computer-generated virtual objects onto the user's view of the real world-has been considered a promising tool. Particularly, in the field of TS, AR can minimize the anatomic challenges of traditional endoscopic or microscopic surgery, aiding in surgical training, preoperative planning and intra-operative orientation. The aim of this systematic review is to analyze the potential future role of augmented reality, both in endoscopic and microscopic transsphenoidal surgeries.

Health-Related Quality of Life and Role of Surgical Treatment in Idiopathic Normal Pressure Hydrocephalus: A Systematic Review

OBJECTIVE

Although shunting has been shown to ameliorate symptoms in idiopathic normal pressure hydrocephalus (iNPH), its impact on health-related quality of life (HRQoL) has yet to be fully elucidated. Patient and caregiver subjective life satisfaction and HRQoL represent crucial indicators for assessing the well-being of individuals facing chronic illnesses, including iNPH. This study aimed to systematically analyze the existing data about HRQoL in iNPH-treated patients to evaluate the role of surgical treatment in such a scenario.

METHODS

Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the literature in the PubMed/Medline, Web of Science, and Scopus databases was searched. Fourteen studies met our inclusion criteria. The Joanna Briggs Institute critical appraisal tool was used to assess the risk of bias.

RESULTS

Overall, HRQoL improved significantly within 1 year after shunt placement although patients with iNPH reported worse HRQoL values compared with healthy-matched individuals. Up to 5 years after shunting, a sustained heterogeneity exists on published data showing improved scores across all domains for at least 21 months after shunting. Further, although surgical treatment can improve HRQoL, long-term follow-up showed that it remained lower than that of healthy controls. These data suggest a significant decrease of HRQoL in patients with iNPH over time after shunting, probably due to aging, comorbidities, and disease progression.

CONCLUSIONS

Despite that iNPH has been recognized as a potentially reversible neurological disorder, the available data about the impact of shunting on the HRQoL are unsatisfactory. To improve the well-informed clinical decision-making, it is essential to reach additional high-quality evidence regarding the effect of shunting on HRQoL. New prospective studies, using validated instruments specifically tailored for assessing HRQoL in patients with iNPH, and improved reporting standards are needed. Current evidence suggests that although shunting can provide initial benefits, affected patients may experience long-term impairment in HRQoL.

The role of neuronal plasticity in cervical spondylotic myelopathy surgery: functional assessment and prognostic implication

Cervical spondylotic myelopathy (CSM) is a degenerative disease representing the most common spinal cord disorder in the adult population. It is characterized by chronic compression leading to neurological dysfunction due to static and dynamic injury of the spinal cord in cervical spine. These insidious damage mechanisms can result in the reorganization of cortical and subcortical areas. The cerebral cortex can reorganize due to spinal cord injury and may play a role in preserving neurological function. To date, the gold standard treatment of cervical myelopathy is surgery, comprising anterior, posterior, and combined approaches. However, the complex physiologic recovery processes involving cortical and subcortical neural reorganization following surgery are still inadequately understood. It has been demonstrated that diffusion MRI and functional imaging and techniques, such as transcranial magnetic stimulation (TMS) or functional magnetic resonance imaging (fMRI), can provide new insights into the diagnosis and prognosis of CSM. This review aims to shed light on the state-of-the-art regarding the pattern of cortical and subcortical areas reorganization and recovery before and after surgery in CSM patients, underlighting the critical role of neuroplasticity.