Advances and technical standards in neurosurgery最新文献

Arachnoid cysts are benign, mostly congenital lesions that are asymptomatic in most patients. In some cases, due to their location or sheer size, they produce a mass effect or hydrocephalic obstruction of the cerebrospinal fluid (CSF) flow and thus might warrant surgical treatment. The goal of the surgery is usually to reduce pressure inside the cysts, to reduce the mass effect, or to restore the CSF pathway. Surgical treatment options are resection, fenestration, or shunting of the cyst. Over the past decades, treatment under sheer endoscopic control either through a tube or via craniotomy of arachnoid cysts has been studied thoroughly and replaced open microsurgical cyst surgery in the opinion of many neurosurgeons. Endoscopic treatment has proven to be a safe and feasible technique for both patients and surgeons. In the following chapter, the authors describe their indications for surgery and pre- and postoperative workup, where precautions should be taken, and discuss the different possibilities and techniques of endoscopic cyst fenestration. The aim is to give detailed instructions and present cases for ventriculocystostomy, cystocisternostomy, ventriculocystocisternostomy, and cystoventriculostomy and point out specifics deemed to be important to avoid complications and to ensure the best possible outcome for each patient.

Introduction: Considerable effort has been made to reduce surgical invasiveness, since Axel Perneczky introduced the supraorbital eyebrow approach as a core part of his keyhole concept in neurosurgery. But a limited approach does not facilitate an already serious and demanding task as aneurysm surgery. In this regard, the enhancement of the visual field before, during, and after microsurgical aneurysm occlusion is a safe and effective method to increase the quality of treatment. Indications/Contraindications: Based on the individual anatomical findings, the supraorbital keyhole approach provides access to most aneurysms of the anterior circulation. The approach is not recommended in large complex aneurysms, giant aneurysms, BA aneurysms located beneath the dorsum sellae, as well as cases of severe subarachnoid hemorrhage (SAH) and expected brain edema.

Complications: Experience with endoscopic procedures in aneurysm surgery is limited to several clinical retrospective articles, and no major complications in conjunction with the endoscope were observed. Outcome and Prognosis: The supraorbital eyebrow approach has a low rate of complications and provides highly favorable cosmetic results. Endoscopic inspection prior to clipping might reduce overexposure and mobilization of the aneurysm. It was found that the rate of intraoperative rupture was decreased. The endoscopic post-clipping control helped significantly to reduce aneurysm remnants and unattended parent, branch, or perforator occlusion.

Conclusion: The supraorbital eyebrow approach is a safe, effective and elegant approach in the treatment of most aneurysms of the anterior circulation. The additional enhancement of the visual field provided by the endoscope before, during, and after microsurgical aneurysm clipping might decrease the rate of intraoperative aneurysm ruptures and unexpected findings concerning aneurysm remnant occlusion and compromise of involved parent, branching, and perforating vessels.

This chapter is intended to provide a brief overview of the optics of surgical microscopes and rigid endoscopes, with the aim of providing the reader with the principles dictating the nature of surgical visualization when either of the visual control systems is used. It is not by any means geared toward elaborating on the detailed optical physics of these systems, which is beyond the scope and objective of this chapter.

Tethered cord syndrome is a condition in which the spinal cord is tethered by pathological structures such as a tight filum terminale, intradural lipomas with or without a connecting extradural component, intradural fibrous adhesions, diastematomyelia, and neural placode adhesions following closure of a myelomeningocele.It usually occurs in childhood and adolescence as the spine grows in length, but it can also develop in adulthood. Symptoms of tethered cord syndrome are slowly progressive and varied. Incorrect diagnosis and inappropriate treatment may be provided if the physician lacks knowledge and understanding of this disease.This chapter aims to describe the pathophysiology, syndromes, diagnostic imaging, surgical treatment, and prognosis of tethered cord syndrome to enhance the understanding of this condition.

Favorable clinical outcomes in adult and pediatric neurosurgical oncology generally depend on the extent of tumor resection (EOR). Maximum safe resection remains the main aim of surgery in most intracranial tumors. Despite the accuracy of intraoperative magnetic resonance imaging (iMRI) in the detection of residual intraoperatively, it is not widely implemented worldwide owing to enormous cost and technical difficulties. Over the past years, intraoperative ultrasound (IOUS) has imposed itself as a valuable and reliable intraoperative tool guiding neurosurgeons to achieve gross total resection (GTR) of intracranial tumors.Being less expensive, feasible, doesn't need a high level of training, doesn't need a special workspace, and being real time with outstanding temporal and spatial resolution; all the aforementioned advantages give a superiority for IOUS in comparison to iMRI during resection of brain tumors.In this chapter, we spot the light on the technical nuances, advanced techniques, outcomes of resection, pearls, and pitfalls of the use of IOUS during the resection of brain tumors.

Surgical approaches directed toward craniovertebral junction (CVJ) can be addressed to the ventral, dorsal, and lateral aspects through a variety of 360° surgical corridors Herein, we report features, advantages, and limits of the updated technical support in CVJ surgery in clinical setting and dissection laboratories enriched by our preliminary surgical results of the simultaneous application of O-arm intraoperative neuronavigation and imaging system along with the 3D-4K EX in TOA for the treatment of CVJ pathologies.In the past 4 years, eight patients harboring CVJ compressive pathologies underwent one-step combined anterior neurosurgical decompression and posterior instrumentation and fusion technique with the aid of exoscope and O-arm. In our equipped Cranio-Vertebral Junction Laboratory, we use fresh cadavers (and injected "head and neck" specimens) whose policy, protocols, and logistics have already been elucidated in previous works. Five fresh-frozen adult specimens were dissected adopting an FLA. In these specimens, a TOA was also performed, as well as a neuronavigation-assisted comparison between transoral and transnasal explorable distances.A complete decompression along with stable instrumentation and fusion of the CVJ was accomplished in all the cases at the maximum follow-up (mean: 25.3 months). In two cases, the O-arm navigation allowed the identification of residual compression that was not clearly visible using the microscope alone. In four cases, it was not possible to navigate C1 lateral masses and C2 isthmi due to the angled projection unfitting with the neuronavigation optical system, so misleading the surgeon and strongly suggesting changing surgical strategy intraoperatively. In another case (case 4), it was possible to navigate and perform both C1 lateral masses and C2 isthmi screwing, but the screw placement was suboptimal at the immediate postoperative radiological assessment. In this case, the hardware displacement occurred 2 months later requiring reoperation.

Pineal lesions represent less than 1% of all brain tumors (Villani et al., Clin Neurol Neurosurg 109:1-6, 2007). The abysmal location and critical neurovascular structures remain a surgical challenge, despite the advent of microneurosurgery. The classical wide surgical suboccipital craniotomy with the supracerebellar infratentorial approach, described by Sir Victor Horsley (Victor, Proc R Soc Med 3:77-78, 1910), is infamous for its considerable surgical morbidity and mortality. This was later upgraded microneurosurgically by Stein to improve surgical outcomes (Stein, J Neurosurg 35:197-202, 1971).Ruge et al. reported the first purely endoscopic fenestration of quadrigeminal arachnoid cysts via this corridor (Ruge et al., Neurosurgery 38:830-7, 1996). A cadaver-based anatomical study by Cardia et al. demonstrated the viability for endoscope-assisted techniques (Cardia et al., J Neurosurg 2006;104(6 Suppl):409-14). However, the first purely endoscopic supracerebellar infratentorial (eSCIT) approach to a pineal cyst was performed in 2008 by Gore et al. (Gore PA et al., Neurosurgery 62:108-9, 2008).Unlike transventricular endoscopy, eSCIT approach poses no mechanical risk to the fornices and can be utilized irrespective of ventricular size. More vascular control and resultant reduction in uncontrolled hemorrhage improve the feasibility of attaining complete resection, especially around corners (Zaidi et al,, World Neurosurg 84, 2015). Gravity-dependent positioning and cerebrospinal fluid (CSF) diversion aid cerebellar relaxation, creating the ideal anatomical pathway. Also, angle of the straight sinus, tentorium, and tectal adherence can often influence the choice of approach; thus direct endoscopic visualization not only counteracts access to the engorged Galenic complex but also encourages sharp dissection of the arachnoid (Cardia et al., J Neurosurg 104:409-14, 2006). These tactics help provide excellent illumination with magnification, making it less fatiguing for the surgeon (Broggi et al., Neurosurgery 67:159-65, 2010).The purely endoscopic approach thwarts the dreaded risk of air embolisms, via simple copious irrigation from a small burr hole (Shahinian and Ra, J Neurol Surg B Skull Base 74:114-7, 2013). The tiny opening and closure are rapid to create, and the smaller wound decreases postoperative pain and morbidity. Recent literature supports its numerous advantages and favorable outcomes, making it a tough contender to traditional open methods.

Objective: Transcortical approaches using a spatula-based retraction system have traditionally been used for the microsurgical resection of deep-seated intraventricular and parenchymal brain tumors. Recently, transparent cylindrical or tubular retractors have been developed to provide a stable corridor to access deeper brain lesions and perform bimanual microsurgical resection. The flexible endoports minimize brain retraction injury during surgery and, along with the superior vision of endoscopes, offer several advantages over standard microsurgery. In this chapter, we describe the surgical technique of the endoport-guided endoscopic excision of deep-seated intraaxial brain tumors.

Methods: The endoscopic endoport technique that we use at our institution for the surgical management of intraventricular and intraparenchymal brain tumors has been described in detail with illustrative cases.

Results: Results from the literature review of intraventricular and intraparenchymal port surgery were analyzed, and the feasibility and safety of this technique were discussed. Surgical complication avoidance and management were highlighted. The port technique offers numerous potential advantages, including (1) reducing focal brain injury by distributing retraction forces homogenously, (2) minimizing white matter disruption and the risk of fascicle injury during cannulation, (3) ensuring the stability of the surgical corridor during the procedure, (4) preventing inadvertent expansion of the corticectomy and white fiber tract dissection throughout surgery, and (5) protecting the surrounding tissues against iatrogenic injuries caused by instrument entry and reentry.

Conclusion: The endoport-assisted endoscopic technique is safe and offers an effective alternative option for the resection of intraventricular and intraparenchymal lesions.

Pediatric epilepsy has a worldwide prevalence of approximately 1% (Berg et al., Handb Clin Neurol 111:391-398, 2013) and is associated with not only lower quality of life but also long-term deficits in executive function, significant psychosocial stressors, poor cognitive outcomes, and developmental delays (Schraegle and Titus, Epilepsy Behav 62:20-26, 2016; Puka and Smith, Epilepsia 56:873-881, 2015). With approximately one-third of patients resistant to medical control, surgical intervention can offer a cure or palliation to decrease the disease burden and improve neurological development. Despite its potential, epilepsy surgery is drastically underutilized. Even today only 1% of the millions of epilepsy patients are referred annually for neurosurgical evaluation, and the average delay between diagnosis of Drug Resistant Epilepsy (DRE) and surgical intervention is approximately 20 years in adults and 5 years in children (Solli et al., Epilepsia 61:1352-1364, 2020). It is still estimated that only one-third of surgical candidates undergo operative intervention (Pestana Knight et al., Epilepsia 56:375, 2015). In contrast to the stable to declining rates of adult epilepsy surgery (Englot et al., Neurology 78:1200-1206, 2012; Neligan et al., Epilepsia 54:e62-e65, 2013), rates of pediatric surgery are rising (Pestana Knight et al., Epilepsia 56:375, 2015). Innovations in surgical approaches to epilepsy not only minimize potential complications but also expand the definition of a surgical candidate. In this chapter, three alternatives to classical resection are presented. First, laser ablation provides a minimally invasive approach to focal lesions. Next, both central and peripheral nervous system stimulation can interrupt seizure networks without creating permanent lesions. Lastly, focused ultrasound is discussed as a potential new avenue not only for ablation but also modulation of small, deep foci within seizure networks. A better understanding of the potential surgical options can guide patients and providers to explore all treatment avenues.

Background: Anterior cranial base meningiomas include those meningiomas originating from the tuberculum sellae, the planum sphenoidale, or the olfactory groove, with surgical excision being the main treatment modality for these tumors. Conventional microscopic and endoscope-assisted versions of the supraorbital keyhole approach via an eyebrow incision emerged into minimally invasive options that are frequently utilized nowadays for treating these tumors. At the early attempts of endoscope-assisted cranial surgery, it was noted that rigid endoscopes enabled overcoming the problem of suboptimal visualization when small exposures are used. The technical specifications and design of the currently available rigid endoscopes are associated with a group of unique features that define the endoscopic view and lay the basis for its superiority over the microscopic view during brain surgery. Notwithstanding, the fully endoscopic or endoscope-controlled version of the supraorbital keyhole approach is not routinely practiced by neurosurgeons, with few series published so far. In this chapter we elaborate on the surgical technique and nuances of the fully endoscopic supraorbital approach for anterior cranial base meningiomas.

Methods: From a prospective database of endoscopic procedures maintained by the senior author, clinical data, imaging studies, operative charts, and videos of cases undergoing fully endoscopic excision of anterior cranial base meningiomas via supraorbital approach were retrieved and analyzed. The pertinent literature was also reviewed.

Results: The surgical technique of the fully endoscopic supraorbital approach for anterior cranial base meningiomas was formulated.

Conclusion: The fully endoscopic supraorbital approach for anterior cranial base meningiomas has many advantages over the conventional procedures. In our hands, the technique has proven to be feasible, efficient, and minimally invasive with excellent results.