Preventing Rupture: Clipping of Unruptured Intracranial Aneurysms

Unruptured intracranial aneurysms (UIAs) represent a major public health issue due to their unpredictable natural history. Whether to actively treat them or to maintain them under observation remains a hotly disputed topic. In this chapter, we present a review of the literature regarding the history of clipping and its use in UIAs, as well as the experience of our senior author in this field. We performed an extensive Medline and Google Academic search of the relevant literature. We have also made a retrospective analysis on patients harboring UIAs and multiple intracranial aneurysms (MIAs) clipped by the senior author between 1997 and 2017. About 89 patients had solitary UIAs, alongside 101 with MIAs possessing 257 individual aneurysms in total. All UIA patients were discharged with a favorable neurological outcome and no mortality. Concerning MIAs, the majority of cases had 2 aneurysms, the highest number being 6. And, 61 patients from this group had a favorable outcome. In the hands of experienced vascular neurosurgeons, clipping remains a safe option for both UIAs and MIAs. This procedure offers a long-lasting protection from aneurysmal rupture. In the future, new clip technologies and intraprocedural methods of verifying vessel patency and aneurysmal occlusion may further enhance postoperative results

The role of the basal cisterns in the development of posterior fossa skull base meningiomas

Meningiomas account for more than 30% of all intracranial brain tumors, with 25% of them originating somewhere along the skull base and about 20% of these located in the posterior fossa. The intimate relation of these tumors with neural and vascular structures make them difficult to treat, both surgically and nonsurgically. Their treatment is further hampered by the lack of definitive recommendations, which is partially due to the fact that there is no general accepted model of classification. The present report proposes a new concept of classification of posterior fossa skull base meningiomas, one that takes into account the intimate relation of these tumors with arachnoid structures, simplifies the overcrowded landscape of their systematization and can be extended to oher skull base locations

Giant trigeminal schwannomas: Case report and a short literature review

Trigeminal schwannomas (TS) are rare tumors that are located in the posterior and middle cranial fossae in about a quarter of the cases. The presentation pattern is different according to the involved compartment and the goal of surgery is complete removal. We present the case of a 35-year old woman who presented a left sided TS extending from the posterior to the middle fossa and cavernous sinus. We review the relevant literature regarding diagnosis and surgical treatment of these tumors

Neurosurgical cadaveric and in vivo large animal training models for cranial and spinal approaches and techniques — a systematic review of the current literature

Introduction. Due to its high complexity, neurosurgery consists of a demanding learning curve that requires intense training and a deep knowledge of neuroanatomy. Microsurgical skill development can be achieved through various models of simulation, but as human cadaveric models are not always accessible, cadaveric animal models can provide a reliable environment in which to enhance the acquisition of surgical dexterity. The aim of this review was to analyse the current role of animal brains in laboratory training and to assess their correspondence to the procedures performed in humans. Material and methods. A Pubmed literature search was performed to identify all the articles concerning training cranial and spinal techniques on large animal heads. The search terms were ‘training model’, and ‘neurosurgery’ in association with ‘animal’, ‘sheep’, ‘cow’, and ‘swine’. The exclusion criteria were articles that were on human brains, experimental fundamental research, or on virtual simulators. Results. The search retrieved 119 articles, of which 25 were relevant to the purpose of this review. Owing to their similar neuroanatomy, bovine, porcine and ovine models prove to be reliable structures in simulating neurosurgical procedures. On bovine skulls, an interhemispheric transcalosal and retrosigmoid approach along with different approaches to the Circle of Willis can be recreated. Ovine model procedures have varied from lumbar discectomies on sheep spines to craniosynostosis surgery, whereas in ex vivo swine models, cadaveric dissections of lateral sulcus, median and posterior fossa have been achieved. Conclusions. Laboratory training models enhance surgical advancements by familiarising trainee surgeons with certain neuroanatomical structures and promoting greater surgical dexterity. The accessibility of animal brains allows trainee surgeons to exercise techniques outside the operating theatre, thus optimising outcomes in human surgical procedures

Our initial experience with ventriculo-epiplooic shunt in treatment of hydrocephalus in two centers

Introduction Hydrocephalus represents impairment in cerebrospinal fluid (CSF) dynamics. If the treatment of hydrocephalus is considered difficult, the repeated revisions of ventriculo-peritoneal (VP) shunts are even more challenging. Objective The aim of this article is to evaluate the efficiency of ventriculo-epiplooic (VEp) shunt as a feasible alternative in hydrocephalic patients. Material and methods A technical modification regarding the insertion of peritoneal catheter was imagined: midline laparotomy 8–10cm long was performed in order to open the peritoneal cavity; the great omentum was dissected between its two layers; we placed the distal end of the catheter between the two epiplooic layers; a fenestration of 4cm in diameter into the visceral layer was also performed. A retrospective study of medical records of 15 consecutive patients with hydrocephalus treated with VEp shunt is also presented. Results Between 2008 and 2014 we performed VEp shunt in 15 patients: 5 with congenital hydrocephalus, 8 with secondary hydrocephalus and 2 with normal pressure hydrocephalus. There were 7 men and 8 women. VEp shunt was performed in 13 patients with multiple distal shunt failures and in 2 patients, with history of abdominal surgery, as de novo extracranial drainage procedure. The outcome was favorable in all cases, with no significant postoperative complications. Conclusions VEp shunt is a new, safe and efficient surgical technique for the treatment of hydrocephalus. VEp shunt is indicated in patients with history of recurrent distal shunt failures, and in patients with history of open abdominal surgery and high risk for developing abdominal complications

Metformin delivery using chitosan-capped gold nanoparticles in glioblastoma cell lines

Introduction: Metformin (MET), an old anti-diabetic drug, has proven unexpected anti-glioblastoma effects, by impacting cell proliferation, migration and invasion. However, its remarkable anti-cancer efficacy is mainly limited to the use of high millimolar concentrations in in vitro studies, which are hard to be attained in the clinical setting. Aim: The aim of this paper was to synthetize gold nanoparticles loaded with MET and to test if an enhanced drug delivery via nanotechnology could overcome the limitations of small drug concentrations. Materials and Methods: Gold nanoparticles were functionalized with chitosan (GNPc) and loaded with 80 µM of MET. Their size, zeta potential and stability were characterized and their internalization within tumor cells was assayed through dark field microscopy. Three primary glioblastoma stem cell lines were treated with 5, 10 and 20 µg/mL concentrations of nanoparticles and irradiated. The anti-tumoral effect was evaluated through the MTT cell viability assay. Results: MET-GNPc are easily synthetized and have a positive zeta potential, spherical shape and a median size of 26 nm. MET-GNPc have an increased cell internalization and affect the viability of all three glioblastoma cell lines used compared to control and free MET. However, their anti-cancer effect is not statistically different when compared to GNPc, although a slight tendency to a better response may be observed. Conclusion:Despite an increased cell internalization, the small micromolar concentrations of metformin does not bring an additional benefit to chitosan-based GNPs. Novel delivery methods being able to carry a higher drug concentration of metformin should be tested

Diagnostic criteria in invasive pituitary adenomas

Pituitary adenomas are benign pituitary primary tumors, the most frequent type of tumor in the pituitary fossa. An important part, around 1/3 of the pituitary adenomas manifests an aggressive behavior, growing faster and invading into parasellar areas (cavernous sinus, neural tissues and bones).Objectives: the first aim of this paper is to review the last findings about invasiveness diagnostic criteria, imagistic and biomarkers, which can be used in the classification of pituitary tumors and also to predict the probability of invasiveness, tumor recurrence and suspicion of malignancy. The second aim is to highlight the morphological and clinic types of invasive pituitary adenomas.Materials and methods: we performed a systematic review and analysis of the published articles, searching PubMed between January 1985 and December 2015. There were selected articles published in English, reviews and abstracts. During the advanced search type in PubMed, combinations of the following keywords were used: “pituitary adenoma”, “invasive”, “aggressive”, “biomarkers”, “classification”, “histological subtypes”, ‘”immunohistochemical markers”.Results: 215 articles were selected, regarding diagnostic, prognostic and therapeutic aspects. There were some histological subtypes of pituitary adenomas known as having an aggressive clinical behavior. Several biomarkers were identified as being associated with the invasive feature: proliferation markers (Ki-67 index, number of mitoses, p53 & p27 expression, microvascularization density, telomerase, topoisomerase 2 Alpha), matrix metalloproteinases, protein kinase C, cyclooxygenase-2, E-cadherin, transcription Factors, genetic alterations (PTTG gene, Galectin-3 protein/ LGALS3 gene), apoptosis markers. Based on their invasion and proliferation characteristics, pituitary tumors are proposed to be classified into five grades (1a, 1b, 2a, 2b, 3), the grade 2b tumor with high risk of recurrence being considered as tumor suspected of malignancy.Conclusions: Using a set of specific biological markers for invasive process, there is hope to establish an early diagnosis and prevention of invasive pituitary adenomas. Due to the fact that aggressive pituitary tumors are generally difficult to manage, unresponsive to therapy, quickly recurrent and associated with poor prognosis, the early diagnosis and the search for new therapeutic approaches is becoming mandatory. Instead of using “invasive” or “aggressive” adenoma, the term “tumor suspected of malignancy” would be used for more accuracy