Application of Machine Learning for Classification of Brain Tumors: A Systematic Review and Meta-Analysis.

BACKGROUND: Classifying brain tumors accurately is crucial for treatment and prognosis. Machine learning (ML) shows great promise in improving tumor classification accuracy. This study evaluates ML algorithms for differentiating various brain tumor types. METHODS: A systematic review and meta-analysis were conducted, searching PubMed, Embase, and Web of Science up to March 14, 2023. Studies that only investigated image segmentation accuracy or brain tumor detection instead of classification were excluded. We extracted binary diagnostic accuracy data, constructing contingency tables to derive sensitivity and specificity. RESULTS: Fifty-one studies were included. The pooled area under the curve for glioblastoma versus lymphoma and low-grade versus high-grade gliomas were 0.99 (95% confidence interval [CI]: 0.98-1.00) and 0.89, respectively. The pooled sensitivity and specificity for benign versus malignant tumors were 0.90 (95% CI: 0.85-0.93) and 0.93 (95% CI: 0.90-0.95), respectively. The pooled sensitivity and specificity for low-grade versus high-grade gliomas were 0.99 (95% CI: 0.97-1.00) and 0.94, (95% CI: 0.79-0.99), respectively. Primary versus metastatic tumor identification yields sensitivity and specificity of 0.89, (95% CI: 0.83-0.93) and 0.87 (95% CI: 0.82-0.91), correspondingly. The differentiation of gliomas from pituitary tumors yielded the highest results among primary brain tumor classifications: sensitivity of 0.99 (95% CI: 0.99-1.00) and specificity of 0.99 (95% CI: 0.98-1.00). CONCLUSIONS: ML demonstrated excellent performance in classifying brain tumor images, with near-maximum area under the curves, sensitivity, and specificity.

Research trends within aneurysmal subarachnoid hemorrhage from 2017 to 2021: a bibliometric study.

Bibliometric analyses are a well-established strategy for understanding the dynamics of publications. Aneurysmal subarachnoid hemorrhage (aSAH) is a hot topic in neurology and neurosurgery research. To perform a bibliometric analysis of recent publications within aSAH. Articles addressing aSAH published between 2017 and 2021 were included and had their information extracted from Scopus. A total of 2177 articles were included. The mean number of citations was 6.18 (95%CI = 5.77-6.59). 2021 and 2020 were the most prolific years. World Neurosurgery (N = 389/2,177 articles; 17,87%) was the leading publisher, and American Journal of Neuroradiology had the highest number of citations per article (14.82) among journals with ≥ 10 publications. Primary research (N = 1624/2177) predominated, followed by case reports (N = 434/2,177). Among secondary studies, systematic reviews (N = 78/119) surpassed narrative reviews (N = 41/119). USA led the number of publications (N = 548/2,177 articles; 25.17%), followed by China (N = 358/2,177 articles; 16.44%). High-income countries had a higher number of publications (N = 1624/2177) and more citations per article (6.84) than middle-income countries (N = 553/2177 and 4.25, respectively). There were zero articles from low-income countries. European and North American institutions had the greatest research impact. There was an increase in the number of published articles in the last few years (2020 and 2021). Many studies had a low level of evidence, whereas interventional studies were uncommon.

Assessing the Capabilities of Transcranial Magnetic Stimulation (TMS) to Aid in the Removal of Brain Tumors Affecting the Motor Cortex: A Systematic Review.

Introduction: The brain tumor is frequently related to severe motor impairment and impacts the quality of life. The corticospinal tract can sometimes be affected depending on the type and size of the neoplasm, so different tools can evaluate motor function and connections. It is essential to organize surgical procedures and plan the approach. Functional motor status is mapped before, during, and after surgery. Studying corticospinal tract status can help map the functional areas, predict postoperative outcomes, and help the decision, reducing neurological deficits, aiming to preserve functional networks, using the concepts of white matters localization and fibbers connections. Nowadays, there are new techniques that provide functional information regarding the motor cortex, such as transcranial magnetic stimulation (TMS), direct cortical stimulation (DCS), and navigated TMS (nTMS). These tools can be used to plan a customized surgical strategy and the role of motor evoked potentials (MEPs) is well described during intra-operative, using intraoperative neuromonitoring. MEPs can help to localize primary motor areas and delineate the cut-off point of resection in real-time, using direct stimulation. In the post-operative, the MEP has increased your function as a predictive marker of permanent or transitory neurological lesion marker. Methods: Systematic review performed in MEDLINE via PUBMED, EMBASE, and SCOPUS databases regarding the post-operative assessment of MEP in patients with brain tumors. The search strategy included the following terms: (("Evoked Potentials, Motor"[Mesh]) AND "Neoplasms"[Mesh]) AND "Transcranial Magnetic Stimulation"[Mesh] AND "Brain Tumor"[Mesh]), the analysis followed the PRISMA guidelines for systematic reviews, the review spanned until 06/04/2021, inclusion criteria were studies presenting confirmed diagnosis of brain tumor (primary or metastatic), patients >18 y/o, using TMS, Navigated TMS, and/or Evoked Potentials as tools in preoperative planning or at the intra-operative helping the evaluation of the neurological status of the motor cortex, articles published in peer-reviewed journals, and written in English or Portuguese. Results: A total of 38 studies were selected for this review, of which 14 investigated the potential of nTMS to predict the occurrence of motor deficits, while 25 of the articles investigated the capabilities of the nTMS technique in performing pre/intraoperative neuro mapping of the motor cortex. Conclusion: Further studies regarding motor function assessment are needed and standardized protocols for MEPs also need to be defined.

Co-Occurrence of Pineal-Region and Pituitary-Stalk Hemangioblastomas in a Patient Presenting with Von Hippel-Lindau Disease ­ A Case Report

Introduction Hemangioblastomas of the pineal region or pituitary stalk are extremely rare. Only two cases of hemangioblastomas involving the pineal region have been reported, and four involving the pituitary stalk. The purpose of the present manuscript is to describe an unusual case of supposed hemangioblastoma found concomitantly in the pineal region and pituitary stalk of a patient diagnosed with Von Hippel-Lindau (VHL) disease. Case Report A 35-year-old female patient with a previous diagnosis of VHL complaining of occipital headaches and balance disturbances for three weeks, who previously had a cerebellar hemangioblastoma resected. The visual characteristics of the tumor suggested a friable vascular lesion with a reddish-brown surface, and an incisional biopsy was performed. The tumor consisted of a dense vascular network surrounded by fibrous stroma abundant in reticulin and composed by both fusiform and dispersed xanthomatous cells; the immunohistochemistry was immunopositive for neuronspecific enolase and immunonegative for epithelial membranous antigen. The patient has been monitored closely for 2 years, and the supratentorial masses have not presented any volume alteration. Conclusion This rare association must be taken into account in patients with VHL disease, or at least be suspected in patients who present a thickening of the pituitary stalk and a pineal-region mass. We believe a biopsy of our asymptomatic patient could have been dangerous due to inherent complications like intraoperative bleeding. We recommend close observation of asymptomatic lesions with MRIs every six months or until the lesions become symptomatic. If the pineal-region tumor does become symptomatic, gross resection via a transcallosal approach would be ideal.

Atypical Virchow-Robin SpacesMimicking Cystic Primary Brain Tumor ­ Clinical Report and Literature Review

The Virchow-Robin spaces (VRSs), which are often incidentally observed in modern structural neuroimaging examinations, are small cystic cavities that usually surround the small arteries and arterioles at the level of basal ganglia, the anterior perforated substance and the thalamic-mesencephalic junction. Typically, they have similar physicochemical characteristics to cerebral spinal fluid (CSF) and there is no contrast enhancement on brain CT andMRI images. Its real meaning is unknown, although some contemporary studies have suggested that it might be related to certain traumatic brain injury or several other central nervous system (CNS) disorders, as degenerative diseases. Occasionally, some wide and atypical VRS may be mistaken for primary cystic brain tumors, especially in the context of large and symptomatic lesions, multiple clustered cysts, cortical lesions and if there is adjacent reactive gliosis. The present paper reports four patients who were affected by atypical VRS mimicking brain tumors that required imaging follow-up or even a biopsy to confirm the diagnosis or to indicate the correct approach. Although it is not so unusual, one of them occurred concomitantly and adjacent to a diffuse glioma (co-deleted 1p19q, WHO-GII).

A Diffuse Leptomeningeal Glioneural Tumor Case Producing Hydrocephalus and Polyradiculopathy

The present report describes the case of a male 17-year-old patient who progressively developed a hydrocephalus and polyradiculopathy due to involvement of central nervous system (CNS) by a diffuse leptomeningeal glioneuronal tumor (DLGNT). The tumor had partial remission in response to the treatment with radiotherapy plus procarbazine, lomustine, and vincristine (PCV) chemotherapy, and the patient had improvement in function and pain levels. The current knowledge about DLGNT, including its clinical manifestations, imaging findings, histological characteristics, and treatment are revised and discussed in the present paper.

Tratamento das hemorragias intracranianas espontâneas: o dilema continua / Treatment of Spontaneous Intracranial Hemorrhages: the Dilemma Continues

Introdução As doenças cerebrovasculares (DCV) são a principal causa de morte no Brasil, sendo um grande problema de saúde pública em todo o mundo. Métodos Revisão da literatura utilizando o banco de dados do MEDLINE. Buscados os termos "intracerebral" e "hemorrhage" presentes no título e no resumo publicados em qualquer data. Resultados As hemorragias intracranianas (HIC) acometem, principalmente, os lobos cerebrais, gânglios da base, tálamo, tronco cerebral (predominantemente a ponte) e cerebelo como resultado da ruptura de vasos cerebrais afetados pelos efeitos degenerativos da hipertensão arterial sistêmica (HAS) ou da angiopatia amiloide. O diagnóstico pode ser feito através da tomografia computadorizada de crânio (TCC), sendo auxiliado pela ressonância nuclear magnética (RNM) do encéfalo e a angiografia dos quatro vasos cerebrais na investigação etiológica. Tratamento: dividido em clínico e cirúrgico. Atualmente, não há consenso sobre a seleção do tipo de tratamento para pacientes com HIC, e esta decisão deve levar em consideração idade do paciente, estado neurológico, tamanho e profundidade do hematoma, presença de hidrocefalia e de efeito compressivo. Os estudos atuais mostram uma tendência de superioridade dos procedimentos cirúrgicos minimamente invasivos, commenor risco de lesão encefálica secundária decorrente do acesso cirúrgico ao hematoma. Conclusão A escolha da melhor estratégia para o tratamento das HIC permanece um desafio e ainda deve ser feita de forma individualizada.

Introduction Cerebrovascular Diseases are the major cause of death in Brazil and a public health issue in the world. Methods Review of the literature using the MEDLINE's data bank. We have searched the keywords "intracerebral" and "hemorrhages" in the title and abstract. Results Intracranial hemorrhages (ICH) affect, mainly, the cerebral lobes, basal ganglia, thalamus, brain stem and the cerebellum as a result of the rupture of diseased cerebral vessels by the effects of hypertension or amyloid angiopathy. Diagnosis can be done with the use of a non-contrast computed tomography (CT), magnetic resonance imaging (MRI) and cerebral angiogram (useful in investigation of the etiology). Treatment can be divided in clinical and surgical. This decision still should be taken considering individual features, such as patient's age and neurological status, hematoma's size and deep, time between ictus and the procedure, presence of hydrocephalus and compressive effects. The studies has shown a preference for the minimally invasive procedures, since the secondary brain lesions caused by the surgery tend to be less. Conclusion The choice of what would be the best strategy to treat the ICH is still a challenge and this decision should be taken individually.

Epidural Capillary Hemangioma of the Thoracic Spine / Hemangioma capilar extradural da coluna torácica

Background Hemangiomas are congenital vascular malformations pathologically considered as harmatomas and classified as capillary, cavernous, arteriovenous or venous, and usually located at soft tissue or bone, mainly in the spinal column. Pure epidural capillary hemangiomas are extremely rare lesions that should be included in the differential diagnosis of spinal epidural lesions; only three patients with epidural capillary hemangiomas have been reported to date. Case Report We report a case of a 57-year-oldman that complained of dorsal and back pain. The neurological examination revealed back tenderness and crural paraparesis. His reflexes were exaggeratedand Babinski signwaspresenton both sides.Amagnetic resonance imaging showed an epidural lesion at the level of T10­12 that demonstrated extension with intense postgadolinium enhancement. These lesions were different from more common lesions, mainly schwanommas, mainly due to the foraminal extension, which sets them apart from cavernous hemangiomas. The surgical ressection was performed. After laminectomy, a reddish epiduralmass that extended intothe right T11­12 foraminawas revealed. Thefeeding vessels had to be identified and divided. In such cases, the surgeonmust carefully dissect the lesion circumferentially away from the dura and employ judicious hemostasis. The patient́s histopathological examination revealed a vascular tumor composed of vessels of several calibers. The imagery obtained from the exams led to the diagnosis of a capillary hemangioma. Conclusions Pure epidural capillary hemangiomas should be included in the differential diagnosis of spinal epidural lesions, mainly schwanommas, especially due to the foraminal extension, which may differentiates them from cavernous hemangiomas. Surgical excision is mandatory and intervertebral foraminal extension may preclude gross total resection.

Introdução Os hemangiomas são malformações vasculares congênitas patologicamente consideradas como hamartomas. Podem ser classificadas como capilar, cavernoso, arteriovenoso ou venoso, e são geralmente localizadas em tecidos moles ou ossos, principalmente na coluna vertebral. Hemangioma capilar epidural puro é uma lesão extremamente rara que deve ser incluída no diagnóstico diferencial das lesões espinais epidurais, foram relatados casos de apenas três pacientes com hemangiomas capilares epidurais. Relato de Caso Relatamos o caso de um homem de 57 anos de idade com queixa de dorsalgia. Ao exame neurológico, paraparesia crural, com hiperreflexia e sinal de Babinski bilateral. A ressonância magnética mostrou uma lesão epidural no nível de T10­12 com intenso realce pós-gadolíneo. Hemangioma capilar deve ser diferenciado de lesões mais comuns, principalmente schwannomas, devido à extensão foraminal. A ressecção cirúrgica foi realizada. Um processo expansivo epidural avermelhado, se estendendo para o forâmen direito de T11­12, tornou-se evidente após a laminectomia. Os vasos que o irrigavam foram identificados e adequadamente separados. A lesão foi cuidadosamente dissecada circunferencialmente e uma hemostasia criteriosa foi realizada. O exame histopatológico revelou um tumor vascular composto por vasos de vários calibres. Exames de imagem corroboraram com a hipótese de um hemangioma capilar. Conclusões Hemangiomas capilares epidurais puros devem ser incluídos no diagnóstico diferencial das lesões da coluna vertebral epidural, principalmente schwanommas, especialmente devido à extensão foraminal. A excisão cirúrgica é obrigatória e a extensão para o forame intervertebral pode impossibilitar a ressecção total.

Traumatic Cervical Artery Dissection and Ischemic Stroke: Anticoagulation or Antiplatelet Therapy? The Controversies Remain / Dissecção traumática da artéria cervical e AVC isquêmico: anticoagulação ou terapia antiplaquetária? A polêmica continua

Arterial dissection of the wall of the carotid artery is a recognized and significant cause of stroke. We described a 22-year-old man presented to the emergency department after a motorcycle accident. He had a right acetabular fracture and had not complained of other symptoms. A few minutes after being admitted, the patient developed left side hemiparesis. Emergency brain magnetic resonance imaging (MRI) revealed an acute ischemia in the left basal ganglia. Conventional angiography confirmed almost complete occlusion of carotid artery lumen. We treated the patient with antiplatelet therapy and he is currently followed at the outpatient clinic with good recovery of motor symptoms. Early identification and management of cervical artery dissection is important, as it is one of the major causes of ischemic stroke in young adults. Despite previous published articles, the best treatment of carotid artery dissection, especially after trauma, remains controversial.

Dissecação da parede da artéria carótida interna é uma causa reconhecida de acidente vascular cerebral. Descrevemos um jovem de 22 anos admitido na emergência após acidente motociclístico. Inicialmente foi diagnosticado somente fratura acetabular, sem nenhuma outra queixa pelo paciente. Poucos minutos após admissão, o paciente evoluiu com hemiparesia esquerda. Encaminhado a ressonânciamagnética do encéfalo em caráter de urgência, identificou-se isquemia aguda nos gânglios da base à esquerda. Angiografia convencional demonstrou oclusão quase completa da artéria carótida interna. O caso foi tratado com terapia antiagregante plaquetária e atualmente o

Dissecação da parede da artéria carótida interna é uma causa reconhecida de acidente vascular cerebral. Descrevemos um jovem de 22 anos admitido na emergência após acidente motociclístico. Inicialmente foi diagnosticado somente fratura acetabular, sem nenhuma outra queixa pelo paciente. Poucos minutos após admissão, o paciente evoluiu com hemiparesia esquerda. Encaminhado a ressonânciamagnética do encéfalo em caráter de urgência, identificou-se isquemia aguda nos gânglios da base à esquerda. Angiografia convencional demonstrou oclusão quase completa da artéria carótida interna. O caso foi tratado com terapia antiagregante plaquetária e atualmente o paciente está em acompanhamento ambulatorial com boa recuperação dos sintomas motores. Como uma das maiores causas de acidente vascular cerebral isquêmico em jovens, a identificação precoce emanejo da dissecação cervical é importante. A depeito dos trabalhos previamente publicados, o melhor tratamento para a dissecação carótidea, especialmente após trauma, permanece controversa.