Treatment strategies for saccular anterior inferior cerebellar artery aneurysms: a systematic review.

INTRODUCTION: The anterior inferior cerebellar artery (AICA) plays a crucial role in cerebellar blood supply, and AICA aneurysms are relatively rare, comprising less than 1-1.5% of all brain aneurysms. Understanding their clinical scenarios, management approaches, and outcomes is essential. This systematic review analyzes data from 86 studies to comprehensively explore AICA aneurysms. MATERIALS AND METHODS: The process of obtaining relevant research, which includes patients with AICA aneurysms, was carried out using the PubMed, Web of Science, and Scopus databases. This review exclusively included extensive papers written in English. The search included the MeSH phrases "Anterior inferior cerebellar artery aneurysm" and "AICA aneurysm." Microsurgical and endovascular treatments were compared using statistical analysis, exploring demographics, risk factors, treatment modalities, and clinical outcomes. RESULTS: The review includes 85 case reports and one retrospective study, totaling 140 patients. The study reveals a diverse patient profile with a slight female predominance (65%), a mean age of 50.7 years, and an 82.86% prevalence of no identified risk factors. Ruptured aneurysms accounted for 55%, with microsurgery and endovascular procedures accounting for 70.71% and 27.86%, respectively. The mortality rate was 2.86%, and no significant differences were found in rebleed, recurrence, or mortality rates between treatment groups. CONCLUSION: Microsurgical and endovascular interventions demonstrate comparable effectiveness, with microsurgery showing superiority in specific situations. Therefore, tailoring treatment is crucial to individual patient needs. Subgroup analyses highlight demographic-specific trends, guiding clinicians in managing this rare pathology.

An In-Depth Analysis of the Artery of Salmon: Anatomy and Neurosurgical Implications.

BACKGROUND: Michel Salmon was a prominent person in the field of plastic surgery during the early 20th century. His pioneering work contributed significantly to our understanding of human anatomy, particularly with the identification of the artery of Salmon (AOS). The objective of this study is to thoroughly investigate the AOS by conducting a comprehensive literature review, providing insights into its anatomy and surgical implications. METHODS: This review was undertaken after a thorough examination of literature encompassing papers about the AOS. Right up until January 2024, databases like PubMed, ScienceDirect, and Web of Science were explored. The search was conducted using specific terms such as "Artery of Salmon," "suboccipital artery," and "vertebral artery anatomy." An in-depth assessment was conducted to examine the anatomy, and surgical significance of the AOS. RESULTS: The AOS is a branch of the V3 segment of the vertebral artery that supplies the suboccipital muscles. The ability, to identify it, is critical for distinguishing the origins of intraoperative hemorrhage. Through careful surgical intervention, the artery was able to devascularize tumors and vascular lesions. We also touched on the technical issues of its possible application in bypass operations for aneurysms of the posterior inferior cerebellar artery or vertebral artery. CONCLUSIONS: The AOS is sometimes vital in neurosurgery, facilitating precise interventions and serving as a conduit in suboccipital bypass surgeries. Understanding its variations is essential for neurosurgeons, showcasing ongoing advancements in patient care.

Unilateral approach for bilateral clipping of posterior communicating artery aneurysms in a hybrid operating room: A technical note.

Bilateral posterior communicating (pComm) artery aneurysms represent only 2% of mirror intracranial aneurysms. Usually, these are surgically approached through bilateral craniotomies for clipping. We present the case of a 50-year-old female presenting with headache and horizontal diplopia. Neurological examination revealed a left oculomotor palsy, with no other neurological deficits. Imaging studies revealed bilateral aneurysmatic lesions in both internal carotid arteries (ICA). A conventional left pterional approach was planned in order to treat the symptomatic aneurysm, and, if deemed feasible, a contralateral clipping through the same approach. The procedure was performed in a hybrid operating room (HOR), performing an intraoperative digital subtraction angiography (DSA) and roadmapping assistance during dissection and clipping. Transoperatively, a post-fixed optic chiasm was identified, with a wide interoptic space, which allowed us to perform the contralateral clipping through a unilateral approach. This technique for clipping bilateral pComm aneurysms can be performed when the proper anatomical features are met.

Relative cerebral blood volume as response predictor in the treatment of recurrent glioblastoma with anti-angiogenic therapy.

BACKGROUND: Glioblastoma is one of the most common brain tumors in adult populations, usually carrying a poor prognosis. While several studies have researched the impact of anti-angiogenic therapies, especially anti-VEFG treatments in glioblastoma, few have attempted to assess its progress using imaging studies. PURPOSE: We attempted to analyze whether relative cerebral blood volume (rCBV) from dynamic susceptibility-weighted contrast-enhanced MRI (DSC-MRI) could predict response in patients with glioblastoma undergoing Bevacizumab (BVZ) treatment. METHODS: We performed a retrospective study evaluating patients with recurrent glioblastoma receiving anti-angiogenic therapy with BVZ between 2012 and 2017 in our institution. Patients were scheduled for routine MRIs at baseline and first-month follow-up visits. Studies were processed for DSC-MRI, cT1, and FLAIR images, from which relative cerebral blood volume measurements were obtained. We assessed patient response using the Response Assessment in Neuro-Oncology (RANO) working group criteria and overall survival. RESULTS: 40 patients were included in the study and were classified as Bevacizumab responders and non-responders. The average rCBV before treatment was 4.5 for both groups, and average rCBV was 2.5 for responders and 5.4 for non-responders. ROC curve set a cutoff point of 3.7 for rCBV predictive of response to BVZ. Cox Multivariate analysis only showed rCBV as a predictive factor of OS. CONCLUSION: A statistically significant difference was found in rCBV between patients who responded and those who did not respond to BVZ treatment. rCBV may be a low-cost and effective marker to assess response to Bevacizumab treatment in GBM.

Foix-Alajouanine Syndrome: A Case Report.

Foix-Alajouanine syndrome is a rare form of presentation of an arteriovenous malformation of the spinal cord that causes myelopathy in the thoracic and lumbar medullary segments. We present the case of a 46-year-old female who suffered from weakness in the lower limbs with sensation loss, low back pain, urinary incontinence, and constipation. The magnetic resonance image T2 sequence of the thoracic spine from T6 to T11 revealed abnormally hypointense signals in the posterior epidural region caused by larger arteries. A spinal digital subtraction angiography was useful to diagnose a right perimedullary fistula with venous drainage, which was satisfactorily embolized. The key to suspecting this diagnosis is the presence of dilated vessels in the posterior epidural space, which are evident in T2 and short tau inversion recovery (STIR)-weighted sequences. Physicians often misdiagnose Foix-Alajouanine syndrome, resulting in potential delays in care. Neurosurgeons can use surgery or endovascular embolization to treat this condition.

Roadmapping technique in the hybrid operating room for the microsurgical treatment of complex intracranial aneurysms.

OBJECTIVE: To describe the roadmapping technique and our three-year experience in the management of intracranial aneurysms in the hybrid operating room. METHODS: We analyzed all patients who underwent surgical clipping for cerebral aneurysms with the roadmapping technique from January 2017 to September 2019. We report demographic, clinical, and morphological variables, as well as clinical and radiological outcomes. We further describe three illustrative cases of the technique. RESULTS: A total of 13 patients were included, 9 of which (69.2%) presented with subarachnoid hemorrhage, with a total of 23 treated aneurysms. All patients were female, with a mean age of 47.7 years (range 31-63). All cases were anterior circulation aneurysms, the most frequent location being the ophthalmic segment of the internal carotid artery (ICA) in 11 cases (48%), followed by posterior communicating in 8 (36%), and ICA bifurcation in 2 (8%). Intraoperative clip repositioning was required in 9 aneurysms (36%) as a result of the roadmapping technique in the hybrid operating room. There were no residual aneurysms in our series, nor reported mortality. CONCLUSIONS: The roadmapping technique in the hybrid operating room offers a complementary tool for the adequate occlusion of complex intracranial aneurysms, as it provides a real time fluoroscopic-guided clipping technique, and clip repositioning is possible in a single surgical stage, whenever a residual portion of the aneurysm is identified. This technique also provides some advantages, such as immediate vasospasm identification and treatment with intra-arterial vasodilators, balloon proximal control for certain paraclinoid aneurysms, and simultaneous endovascular treatment in selected cases during a single stage.

Intra-aneurysmatic thrombectomy in a distal anterior cerebral artery aneurysm.

Thrombectomy procedures following intra-aneurysmatic lesions are extremely rare, and few cases have been reported. This article describes a microsurgical intra-aneurysmatic thrombectomy (MIaT) for a distal anterior cerebral artery (DACA) aneurysm. We present the case of a 48-year-old female that was admitted to the emergency room, showing neurologic deterioration with focal deficits. A computed tomography angiography (CTA) scan revealed an aneurysm located in the distal segment of the left anterior cerebral artery. During the surgical procedure, after clipping, a wellformed clot was visualized through the aneurysm's wall obstructing the left DACA flow. We proceeded to open the aneurysm's dome to remove the thrombus and clip the aneurysm neck, re-establishing the flow of the left DACA. Intra-aneurysmatic thrombosis can occur as a complication during clipping, obstructing the distal flow of vital arteries and causing fatal results in the patient's postoperative status. MIaT is a good technique for restoring the flow of the affected vessel and allows a secure aneurysm clipping after thrombus removal.

Motor outcome after resective surgery for the central lobe gliomas.

Background: Extent of resection (EOR) plays a major role in the prognosis on patients with gliomas, although the postoperative functionality of the patient is of great importance as well. It is why many surgeons advocate to not operate extensively on tumors that involve eloquent regions such as the central lobe. Recent series have demonstrated that it is possible to achieve extensive resections in this area without significantly affecting the functional outcome for these patients. We illustrate this issue with the experience obtained at the National Institute of Neurology and Neurosurgery in Mexico City. Methods: This is an observational and retrospective study that included patients that received surgical resection for intracranial gliomas that involved the central lobe at the National Institute of Neurology and Neurosurgery of Mexico, between January 2017 and May 2020. Demographic and clinical variables of the patients at the time of diagnosis were collected as well as tumor morphological variables, surgical adjuncts, and clinical outcomes. Statistical analysis was performed with SPSS software. Results: A total of 28 patients were included in the study with 43% of patients having a motor deficit before surgery. The average EOR was 88.6%. Patients presented with worsening of their motor status in the immediate postoperative period in 21% of the cases, although most of the patients recovered within the 1st month of follow-up. After analyzing all variables, not having a presurgical motor deficit was a statistically significant risk factor for developing a new motor deficit in the immediate postoperative period (P: 0.02). Conclusion: A resective surgery for gliomas near or within the central lobe can be performed safely and a satisfactory motor outcome for patients can be achieved without sacrificing the EOR. An intact presurgical motor status is a risk factor for developing a new deficit after surgery.

Surgical Approach and Further Management of Intracranial Hemangioendothelioma With Double Location: A Case Report.

Hemangioendotheliomas are highly vascularized lesions, and their intracranial presentation is extremely rare. We present the case of a 65-year-old female patient who was evaluated for cranial deformity, headache, and left hemiplegia. Two bone lesions that were destroying and expanding the bone diploe with intracranial extension were identified in the fronto-temporal and parietal regions. Both lesions were multilobed and showed heterogeneous behavior. Mixed hemangioendotheliomas were identified after the successful resection of both tumors in two separate surgical procedures. The prognosis of this type of tumor with an intracranial location is not well-defined because there are too few reported cases.

Reconversion of neurosurgical practice in times of the SARS-CoV-2 pandemic: a narrative review of the literature and guideline implementation in a Mexican neurosurgical referral center.

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has forced the modification of surgical practice worldwide. Medical centers have been adapted to provide an efficient arrangement of their economic and human resources. Although neurosurgeons are not in the first line of management and treatment of COVID-19 patients, they take care of patients with neurological pathology and potential severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Here, the authors describe their institutional actions against the pandemic and compare these actions with those in peer-reviewed publications. METHODS: The authors conducted a search using the MEDLINE, PubMed, and Google Scholar databases from the beginning of the pandemic until July 11, 2020, using the following terms: "Neurosurgery," "COVID-19/SARS-CoV-2," "reconversion/modification," "practice," "academy," and "teaching." Then, they created operational guidelines tailored for their institution to maximize resource efficiency and minimize risk for the healthcare personnel. RESULTS: According to the reviewed literature, the authors defined the following three changes that have had the greatest impact in neurosurgical practice during the COVID-19 pandemic: 1) changes in clinical practices; 2) changes in the medical care setting, including modifications of perioperative care; and 3) changes in the academic teaching methodology. CONCLUSIONS: The Instituto Nacional de Neurología y Neurocirugía "Manuel Velasco Suárez" is one of the major referral centers for treating highly complex neurosurgical pathologies in Mexico. Its clinical and neurosurgical practices have been modified with the implementation of specific interventions against the spread of COVID-19. These practical and simple actions are remarkably relevant in the context of the pandemic and can be adopted and suited by other healthcare centers according to their available resources to better prepare for the next event.

Current Approach of Functioning Head and Neck Paragangliomas: Case Report of a Young Patient with Multiple Asynchronous Tumors.

Introduction. Pheochromocytomas (Pheo) and paragangliomas (PGL) are rare neuroendocrine tumors arising from chromaffin cells of the adrenal medulla and from the extra-adrenal autonomic paraganglia, respectively. Only 1-3% of head and neck PGL (HNPGL) show elevated catecholamines, and at least 30% of Pheo and PGL (PCPG) are associated with genetic syndromes caused by germline mutations in tumor suppressor genes and proto-oncogenes. Clinical Case. A 33-year-old man with a past medical history of resection of an abdominal PGL at the age of eleven underwent a CT scan after a mild traumatic brain injury revealing an incidental brain tumor. The diagnosis of a functioning PGL was made, and further testing was undertaken with a PET-CT with 68Ga-DOTATATE, SPECT-CT 131-MIBG, and genetic testing. Discussion and Conclusion. The usual clinical presentation of functioning PCPG includes paroxistic hypertension, headache, and diaphoresis, sometimes with a suggestive family history in 30-40% of cases. Only 20% of PGL are located in head and neck, of which only 1-3% will show elevated catecholamines. Metastatic disease is present in up to 50% of cases, usually associated with a hereditary germline mutation. However, different phenotypes can be observed depending on such germline mutations. Genetic testing is important in patients with PCPG since 31% will present a germline mutation. In this particular patient, an SDHB gene mutation was revealed, which can drastically influence the follow-up plan and the genetic counsel offered. A multidisciplinary approach is mandatory for every patient presenting with PCPG.SDHB gene mutation was revealed, which can drastically influence the follow-up plan and the genetic counsel offered. A multidisciplinary approach is mandatory for every patient presenting with PCPG.

Linfoma primario del sistema nervioso central: experiencia clínica en un centro neurológico / Primary central nervous system lymphoma: clinical experience in a neurological center

Introducción. El linfoma primario del sistema nervioso central es una variedad de linfoma no Hodgkin que representa el 4-5% de los tumores intracraneales y el 5% de todos los linfomas. Se origina en el encéfalo, los ojos, la leptomeninge y la médula espinal sin evidencia sistémica de actividad linfomatoide; el subtipo de linfoma mayoritariamente es de células de tipo B. Pacientes y métodos. Estudio descriptivo de los pacientes diagnosticados con linfoma cerebral primario que fueron atendidos en centros de tercer nivel en México entre los años 1980 y 2016. Se incluyó a los pacientes que contaran con cribado para búsqueda de linfoma sistémico. Los resultados se analizaron mediante frecuencias simples; en el caso del tiempo libre de enfermedad y supervivencia global, mediante curvas de Kaplan-Meier, y las diferencias entre curvas, mediante log rank. Resultados. En un total de 215 pacientes sólo hubo 74 casos. El 45% fueron mujeres y el 55%, hombres. El 36,7% eran mayores de 60 años. Las manifestaciones clínicas más frecuentes fueron déficit motor (60%) y alteraciones cognitivas (52%). La mayoría recibió alguna forma de quimioterapia (89%). El único factor significativo para respuesta radiológica y pronóstico clínico era el uso combinado de radioquimioterapia (p = 0,04493). Conclusión. El linfoma representa una patología tumoral con alta respuesta clinicorradiológica al tratamiento, aunque la respuesta no es duradera. Es fundamental su identificación temprana y el tratamiento multidisciplinario para el mejor pronóstico de estos pacientes

Introduction. Primary lymphoma of the central nervous system is a variety of non-Hodgkin’s lymphoma that accounts for 4-5% of intracranial tumours and 5% of all lymphomas. It has its origin in the brain, the eyes, the leptomeninges and the spinal cord with no systemic evidence of lymphomatoid activity; the subtype of lymphoma is predominantly of B-type cells. Patients and methods. We conducted a descriptive study of the patients diagnosed with primary brain lymphoma who were attended to at third-level centres in Mexico between the years 1980 and 2016. Patients who had been screened for systemic lymphoma were included. The results were analysed by means of simple frequencies, and disease-free and overall survival time was analysed by Kaplan-Meier curves; the differences among curves were analysed by means of log rank. Results. Of a total of 215 patients, there were only 74 cases. By sex, 45% were females and 55% were males. Regarding age, 36.7% were over 60 years old. The most frequent clinical manifestations were motor loss (60%) and cognitive disorders (52%). Most patients received some form of chemotherapy (89%). The only significant factor for radiological response and clinical prognosis was the combined use of radiochemotherapy (p = 0.04493). Conclusion. Lymphoma is a tumorous condition with a high clinicoradiological response to treatment, although the response is not long-lasting. Its early identification and multidisciplinary management are essential for a more favourable prognosis in these patients

Radioterapia más temozolomida o PCV en pacientes con oligodendroglioma anaplásico con codeleción 1p19q / Radiotherapy plus temozolomide or PCV in patients with anaplastic oligodendroglioma 1p19q codeleted

Introducción. La hipotonía constituye un signo habitual de enfermedad en el neonato. Ahora bien, se trata de un signo inespecífico: puede ser la manifestación inicial de una enfermedad neurológica o multisistémica. Objetivos. Estudiar las principales causas de la hipotonía neonatal y evaluar la exactitud diagnóstica de la anamnesis y la exploración física en el neonato hipotónico. Pacientes y métodos. Estudio retrospectivo de 22 años con recién nacidos afectados por hipotonía e ingresados en la unidad de cuidados intensivos neonatales. A partir de la anamnesis y de los datos recabados durante la exploración física, se hizo una clasificación inicial en condiciones de enmascaramiento del tipo de hipotonía: central, periférica o indeterminada. Resultados. El número de pacientes estudiados ascendió a 91. De ellos, 42 (46,2%) presentaban antecedentes de alteraciones prenatales: polihidramnios (28,6%), retraso del crecimiento intrauterino (21,4%) y presentación de nalgas (19%). Cincuenta y tres (58,2%) habían precisado reanimación al nacer. Los principales síntomas asociados consistieron en disnea (65,9%), dificultades de alimentación (36,5%) y escasez de movimientos espontáneos (22,4%). El diagnóstico definitivo se obtuvo en 64 neonatos (70,3%): el 81,3% mostraba hipotonía central, y el 18,7%, hipotonía periférica. El valor predictivo positivo de la clasificación inicial alcanzó el 97,9% en la hipotonía central y el 66,7% en la hipotonía periférica. La tasa de mortalidad fue del 8,8%, y resultó superior en el grupo de hipotonía periférica (58,3% frente a 1,3%). Conclusiones. La hipotonía neonatal aparece vinculada con una larga lista de trastornos. Una anamnesis minuciosa y una valoración neurológica cuidadosa brindan un alto valor predictivo diagnóstico que debe orientar el estudio etiológico

Introduction. Radiotherapy with procarbazine, lomustine, and vincristine (PCV) improves overall survival in patients with anaplastic oligodendroglioma 1p19q codeleted. Patients and methods. This retrospective analysis investigated outcomes in patients with anaplastic oligodendroglioma 1p19q codeleted compared two different protocols (radiotherapy plus temozolomide or PCV). The primary end points were overall survival and progression-free survival. Secondary endpoint was the radiological response. Results. A total of 48 patients were included. Mean age was 43 years (range: 19-66 years), 26 were male (54.1%). Twenty-one patients received PCV and 27 temozolomide. The baseline characteristics were not difference between the groups. The progression-free survival and overall survival in the PCV group were 7.2 and 10.6 years respectively and temozolomide were 6.1 and 9.2 years, both statistically significant. The radiological response was present in 80.9% in PCV arm and 70.2% in temozolomide arm there was not statistical differences. The multivariate Cox model showed only the significant parameters the use of PCV protocol. The toxicity grade 3 or 4 was present in 42.8% in PCV arm and 11.1% in temozolomide arm. Conclusions. The most common strategy in the Latin America community is the substitution of the PCV or temozolomide. This retrospective study showed superior efficacy of PCV than temozolomide. The Latin American community effort must be made to be able to have the drugs to available for using as a first line of treatment

[Primary Tumors of the Central Nervous System. Clinical Experience at a Third Level Center].

Background: Central nervous system (CNS) tumors are a group of neoplasms that originate from various cells in the CNS. The increasing incidence and prevalence of this type of tumor in developing countries are striking; however, there are few current studies in Latin America including Mexico estimating the impact of these pathological entities on the general population. Objective: The objective of the study was to study the characteristics of primary CNS tumors over a period of 52 years. Methods: A review of records from patients with a histopathological diagnosis of CNS neoplasm over a period of 52 years was conducted at a tertiary-care academic medical center. Patients were grouped by sex, age, and the tumor's anatomical location. Results: A sample of 9615 patients with tumor lesions was obtained; 51% were female, 49% were male, and their mean age was 42 years. The tumors with the highest prevalence were neuroepithelial tumors (38.6%), followed by meningeal tumors (22.8%). Neuroepithelial tumors accounted for 64% in the group of patients under 40 years of age and 56% among those above 40 years of age. The most frequently involved location was supratentorial, in 78.9% of cases. Conclusions: Although retrospective in nature and based on a small sample, this study reports the epidemiology and characteristics of primary brain tumors in the Mexican population.