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Polymorphous low-grade neuroepithelial tumor of the young (PLNTY) is a recently recognised tumor type with indolent behaviour with characteristic imaging and histomolecular features. We describe the clinical, imaging, histo-molecular features of 15 cases diagnosed as low-grade glioma suggestive of PLNTY, over a period of 3 years. Immunohistochemistry (IHC) and fluorescence in situ hybridisation were used to assess molecular alterations. The tumors were seen predominantly in children (range 5-65 years). Most of the patients presented with history of seizures. Imaging revealed cortical-subcortical well demarcated solid-cystic tumor with intratumoral calcification. Histopathology revealed a low-grade tumor with oligodendroglia-Iike cells admixed with astrocytic cells immunopositive for CD34. BRAF p.V600E mutations and FGFR2 breakapart were observed in six cases each, while three showed FGFR3 breakapart. FGFR2 breakapart positive PLNTY were seen in children exclusively. The majority of cases were seizure free post-surgery, except two patients who succumbed to the illness. PLNTY, needs to be considered as a prime differential diagnosis in a solid-cystic tumor in a young patient with history of seizures. Characteristic clinical features, radiology, histomorphology with an IHC panel of OLIG2, GFAP and CD34 correlates with one of the MAPK alterations in PLNTY (BRAF p.V600E, FGFR2/3 gene rearrangement). In a resource limited setting, this limited panel may be sufficient for a correlative diagnosis.
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INTRODUCTION: Meningiomas located in the posterior fossa and involving the sinodural angle at the junction of the transverse and sigmoid sinuses are uncommon and present unique challenges due to their complex anatomical location. Despite their distinctive features, they are frequently categorized with tentorial meningiomas in the literature. MATERIALS AND METHODS: This retrospective study conducted at a tertiary care center involved 64 patients with sinodural meningiomas who underwent surgical treatment between 2010 and 2023. The analysis covered demographics, clinical presentation, radiological characteristics, surgical approaches, histopathological findings, and outcomes. RESULTS: The cohort predominantly comprised females (83 %) with a mean age of 47.64 years. Headache (92.2 %) and gait disturbances (62.5 %) were the most common presenting symptoms. Preoperative imaging showed sinus involvement in 57.8 % of cases, predominating Sindou's type 1 and type 6. Gross total resection (Simpson grades 1-2) was achieved in 40.6 % of cases. Postoperative complications included pseudomeningocele (9.4 %), especially in patients with hydrocephalus. CONCLUSION: Sinodural meningiomas represent a distinct subset of posterior fossa tumors, necessitating meticulous preoperative planning and intraoperative decision-making regarding sinus management. The study underscores the importance of individualized surgical strategies and highlights the role of radiosurgery in managing residual disease effectively.
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INTRODUCTION: Diffuse midline glioma (DMG) is a relatively new entity which was introduced in the fourth edition of the WHO classification of CNS tumours in 2016 and later underwent revision in 2021. It is an infiltrative glioma arising from midline structures, viz., thalamus, spine, and brainstem. Current literature on DMG is based majorly on brainstem lesions, and DMGs arising elsewhere remain unexplored. In our study, we have discussed our experience with thalamic DMGs. METHODOLOGY: This is a retrospective observational study of all patients with histopathologically proven DMG H3K27M altered, arising in the thalamus from 2018 to 2022. Clinical, neuroimaging, and pathology were re-reviewed, and prognostic factors for 3 months, 6 months, and overall survival (OS) were analyzed for all patients. RESULTS: There were 89 patients- 64 adults and 25 pediatric patients with thalamic DMG. The median age at presentation was 24 years. Raised ICP followed by limb weakness were the most common presenting complaints. Stereotactic biopsy was performed in 64 (71.9â¯%) patients and surgical decompression in 25 (28.1â¯%) patients. CSF diversion was required in 53 (59.6â¯%) patients. Median survival was 8 months in adults and 7 months in pediatric (p-value: 0.51). Raised ICP and TP53 mutation were prognostic factors in pediatric population. Radiotherapy with or without chemotherapy improved survival (p-value- <0.01). CONCLUSION: Thalamic DMGs have a poor prognosis which is comparable to brainstem DMGs. Radiotherapy improves survival in these patients. However, the disease remains an enigma and further work delving into its molecular characterization should be encouraged.
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Neoplasias Encefálicas , Glioma , Tálamo , Humanos , Masculino , Femenino , Adulto , Tálamo/patología , Tálamo/diagnóstico por imagen , Estudios Retrospectivos , Adulto Joven , Niño , Glioma/patología , Glioma/terapia , Glioma/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/diagnóstico por imagen , Adolescente , Persona de Mediana Edad , PreescolarRESUMEN
Trigonal meningiomas are rare intraventricular tumours that present a surgical challenge. There is no consensus on the optimal surgical approach to these lesions, though the transtemporal and transparietal approaches are most frequently employed. We aimed to examine the approach-related morbidity and surgical nuances in treating trigonal meningiomas. This retrospective review assimilated data from 64 trigonal meningiomas operated over 15 years. Details of clinicoradiological presentation, surgical approach and intraoperative impression, pathology and incidence of various postoperative deficits were recorded. In our study, Trigonal meningiomas most frequently presented with headache and visual deterioration. The median volume of tumours was 63.6cc. Thirty-one meningiomas each (48.4%) were WHO Grade 1 and WHO Grade 2, while 2 were WHO Grade 3. The most frequent approach employed was transtemporal (38 patients, 59.4%), followed by transparietal (22 patients, 34.4%). After surgery features of raised ICP and altered mental status resolved in all patients, while contralateral limb weakness resolved in 80%, aphasia in 60%, seizures in 70%, and vision loss in 46.2%. Eighteen patients (28.13%) developed transient postoperative neurological deficits, with one patient (1.5%) developing permanent morbidity. Surgery for IVMs results in rapid improvement of neurological status, though visual outcomes are poorer in patients with low vision prior to surgery, longer duration of complaints and optic atrophy. The new postoperative deficits in some patients tend to improve on follow up. Transtemporal and transparietal approaches may be employed, based on multiple factors like tumour extension, loculation of temporal horn, size of lesion with no significant difference in their safety profile.
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Neoplasias Meníngeas , Meningioma , Procedimientos Neuroquirúrgicos , Complicaciones Posoperatorias , Humanos , Meningioma/cirugía , Meningioma/complicaciones , Femenino , Masculino , Persona de Mediana Edad , Adulto , Anciano , Resultado del Tratamiento , Estudios Retrospectivos , Neoplasias Meníngeas/cirugía , Procedimientos Neuroquirúrgicos/métodos , Complicaciones Posoperatorias/epidemiología , Neoplasias del Ventrículo Cerebral/cirugía , Adulto JovenRESUMEN
INTRODUCTION: Meningiomas are the most common primary intracranial tumour. Gamma knife radiosurgery (GKRS) is a frequently employed non-invasive method of treatment, with good remission rates and low morbidity in literature. However, the role of GKRS in the management of "large" meningiomas is unclear, with reported outcomes that vary by centre. We aimed to assess the factors that influence long-term outcomes following GKRS in meningiomas >10 cc in volume. METHODS: A retrospectively analysed all patients with meningiomas exceeding 10 cc in volume who underwent GKRS between January 2006 and December 2021 at the National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru. Demographic, clinical, radiological, and follow-up data were acquired, and factors associated with progression following GKRS were assessed. RESULTS: The cohort comprised 76 patients 29 males (38.2%) and 47 females (61.8%) with a mean age of 46.3 ± 11.02 years. Thirty-nine patients had been previously operated (51.3%). Meningiomas were most frequently located in the parasagittal region (26 tumours, 34.2%) and sphenopetroclival region (23 tumours, 30.3%), with mean lesion volume of 12.55 ± 5.22 cc, ranging 10.3 cc-25 cc. The mean dose administered to the tumour margin was 12.5 Gy ± 1.2 Gy (range 6-15 Gy). The median duration of clinical follow-up was 48 months, over which period radiological progression occurred in 14 cases (20%), with unchanged tumour volume in 20 cases (28.6%) and reduction in size of the tumour in 36 cases (51.4%). Progression-free survival after GKRS was 72% at 5 years, was significantly poorer among meningiomas with tumour volume >14 cc (log-rank test p = 0.045), tumours presenting with limb motor deficits (log-rank test p = 0.012), and tumours that underwent prior Simpson grade 3 or 4 excision (log-rank test p = 0.032). CONCLUSIONS: Meningiomas >10 cc in volume appear to display a high rate of progression and subsequent need for surgery following GKRS. Primary surgical resection, when not contraindicated, may be considered with GKRS serving an adjuvant role, especially in tumours exceeding 14 cc in volume, and presenting with limb motor deficits. Long-term clinical and radiological follow-up is essential following GKRS as the response of large meningiomas may be unpredictable.
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Neoplasias Meníngeas , Meningioma , Radiocirugia , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Meningioma/radioterapia , Meningioma/cirugía , Neoplasias Meníngeas/radioterapia , Neoplasias Meníngeas/cirugía , Resultado del Tratamiento , Estudios Retrospectivos , Estudios de SeguimientoRESUMEN
INTRODUCTION: Resection of meningiomas (THMs) at the torcular Herophili poses challenges to surgeons due to complex regional anatomy. The current study aims to evaluate factors affecting the extent of resections, progression-free survival, and the role of radiation. METHODS: We did a retrospective study of all the THM patients treated at our institute between May 1987 and June 2022. The demographic data, signs and symptoms, surgical notes, postoperative details, and radiotherapy were gathered retrospectively. Survival analysis was done with Kaplan-Meier tests along with predictors of the extent of resection as well as recurrence. RESULTS: A total of 39 patients qualified to be included in the study, with 10 male patients (male:female 1:2.9) and an average age of 50.8 years. The average follow-up duration was 75.9 months. Simpson's grade 2 excision was achieved in 19 (48.7%) patients, followed by Simpson's grade 3 excision in 17 patients (43.6%). Progression-free survival in subtotal resection was 60 months, and 100 months in gross total resection. Statistically, the extent of the resection was determined by the involvement of sinuses/torcula and the number of quadrants involved around torcula. A total of 16 patients received radiosurgery for the residual or small reccurrence of the lesion. Follow-up revealed reccurrence in 5 cases. CONCLUSIONS: Torcular meningiomas are relatively uncommon, described in few reports, and represent a therapeutic dilemma. Though some experts recommend complete removal of tumor and reconstruction of the sinus, others suggest maximum safe resection, followed by radiosurgery. The present study reflects reasonable control of the residual lesion with radiosurgery after maximum safe resection.
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Neoplasias Meníngeas , Meningioma , Radiocirugia , Humanos , Masculino , Femenino , Persona de Mediana Edad , Meningioma/radioterapia , Meningioma/cirugía , Meningioma/patología , Neoplasias Meníngeas/radioterapia , Neoplasias Meníngeas/cirugía , Neoplasias Meníngeas/patología , Estudios Retrospectivos , Resultado del Tratamiento , Senos Craneales/cirugía , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/patologíaRESUMEN
Hermite-scan (H-scan) imaging is a tissue characterization technique based on the analysis of raw ultrasound radio frequency (RF) echoes. It matches the RF echoes to Gaussian-weighted Hermite polynomials of various orders to extract information related to scatterer diameter. It provides a color map of large and small scatterers in the red and blue H-scan image channels, respectively. H-scan has been previously reported for characterizing breast, pancreatic, and thyroid tumors. The present work evaluated H-scan imaging to differentiate glioblastoma tumors from normal brain tissue ex vivo. First, we conducted 2-D numerical simulations using the k-wave toolbox to assess the performance of parameters derived from H-scan images of acoustic scatterers (15-150 µm diameters) and concentrations (0.2%-1% w/v). We found that the parameter intensity-weighted percentage of red (IWPR) was sensitive to changes in scatterer diameters independent of concentration. Next, we assessed the feasibility of using the IWPR parameter for differentiating glioblastoma and normal brain tissues (n = 11 samples per group). The IWPR parameter estimates for normal tissue (44.1% ± 1.4%) were significantly different (p < 0.0001) from those for glioblastoma (36.2% ± 0.65%). These findings advance the development of H-scan imaging for potential use in differentiating glioblastoma tumors from normal brain tissue during resection surgery.
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Glioblastoma , Humanos , Glioblastoma/diagnóstico por imagen , Ultrasonografía/métodos , Distribución Normal , Algoritmos , Encéfalo/diagnóstico por imagenRESUMEN
BACKGROUND: Benign Nerve sheath tumors (NST) comprise almost one-third of primary spinal tumours. The majority are sporadic. They have low rates of recurrence but an occasional recurrence may need re-surgery. The present study was designed to identify the variables that can predict the risk of their recurrence. METHODS: A retrospective chart review was done including all the histologically proven benign spinal NSTs operated between 2001 and 2019 in our institute. Demographic, operative and postoperative follow-up data were recorded. Recurrence was defined as local reappearance after definite surgical excision or symptomatic increase in size of a residual tumour on follow-up imaging studies. Statistical analysis was done to determine the significant variables associated with local recurrence. RESULTS: 457 patients with a median age of 38 years operated for 459 NSTs qualified for the study. The most frequent location of occurrence of tumours was found to be Low Cervical level (C3-C7 levels). Majority of Schwannoma were located intradurally while Neurofibroma were dumb-bell shaped and extradural. Most of the tumours had solid consistency. Post operatively, 7.7% patients developed complications. 7.8% tumours developed local recurrence after median period of 12 months. The patients developing recurrence were younger compared to nonrecurring tumors. On univariate analysis, male gender, Low cervical and Cervicothoracic junction location were associated with higher recurrence. On multivariate analysis, location at Cervicothoracic junction reached significance. CONCLUSION: Overall recurrence risk among all NST was 7.8% with a median progression free survival of 36 months. The location of tumour at cervicothoracic location was the significant risk factors for recurrence of tumour in our study.
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Neoplasias de la Vaina del Nervio , Neurilemoma , Neurofibroma , Humanos , Masculino , Adulto , Estudios Retrospectivos , Neoplasias de la Vaina del Nervio/diagnóstico , Neoplasias de la Vaina del Nervio/cirugía , Neurilemoma/cirugía , Estudios de Seguimiento , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/cirugía , Resultado del TratamientoRESUMEN
BACKGROUND: Total intravenous anesthesia with propofol can be administered by target-controlled infusion pumps, which work on the principles of pharmacokinetic modeling. While designing this model, neurosurgical patients were excluded as the surgical site and drug action site remained the same (brain). Whether the predicted set propofol concentration and the actual brain site concentration correlate, especially in neurosurgical patients with impaired blood-brain barrier (BBB), is still unknown. In this study we compared the set propofol effect-site concentration in the target-controlled infusion pump with actual brain concentration measured by sampling the cerebrospinal fluid (CSF). METHODS: Consecutive adult neurosurgical patients requiring propofol infusion intraoperatively were recruited. Blood and CSF samples were collected simultaneously when patients received propofol infusion at 2 different target effect-site concentrations-2 and 4 ug/mL. To study BBB integrity, CSF-to-blood albumin ratio and imaging findings were compared. The propofol level in the CSF was compared with set concentration using the Wilcoxon signed-rank test. RESULTS: Fifty patients were recruited, and the data were analyzed from 43 patients. There was no correlation between propofol concentration set in TCI and propofol concentration measured in blood and CSF. Though imaging findings were suggestive of BBB disruption in 37/43 patients, the mean (±standard deviation) CSF-to-serum albumin ratio was 0.0028 ± 0.002, suggesting intact BBB integrity (ratio >0.3 was considered as disrupted BBB). CONCLUSIONS: CSF propofol level did not correlate with set concentration in spite of acceptable clinical anesthetic effect. Also, the CSF-to-blood albumin measurement did not provide information on the BBB integrity.
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Propofol , Adulto , Humanos , Anestésicos Intravenosos , Infusiones Intravenosas , Encéfalo , AlbúminasRESUMEN
Goal: Conventionally, a surgeon's skill is assessed through visual observation by experts and by tracking patient outcomes. These techniques are very subjective and demands enormous time and effort. Hence, the aim of this study is to construct a framework for automated objective assessment of micro-neurosurgical skill. Methods: A mask region-based convolution neural network (RCNN) is trained to identify and localize instances of surgical instruments from the recorded neurosurgery videos. Then the tool motion and tool handling metrics are computed by tracking the detected instrument locations through time. Microscope adjustment patterns are also investigated via the proposed time based metrics.Results: This study highlights the metrics that could potentially emphasize the variance in expertise between a veteran and a novice. These variations include an expert exhibiting a lower velocity, lower acceleration, lower jerks, reduced path length, higher normalized angular displacement, increased bi-manual handling, shorter idle time and smaller inter tool-tip distances while handling tools accompanied with frequent microscope adjustments and reduced maximum and median intervals between adjustments when compared to a novice. Conclusions: The developed vision based framework has proven to be a reliable method to assess the degree of surgical skill objectively and offer prompt and precise feedback to the neurosurgeons.
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Introduction Gamma Knife radiosurgery (GKRS) is an effective treatment for benign vestibular schwannomas (VSs). The established cutoffs have recently been challenged, as recent literature expanded the horizon of GKRS to larger tumors. Even though microsurgery remains the primary option for large VS, GKRS can provide reasonable tumor control and is more likely to avoid cranial neuropathies associated with open surgery. Methods We analyzed patients with VS with volume exceeding 10 cm 3 who underwent GKRS at our center from January 2006 to December 2016. Clinicoradiological and radiosurgical data were collected from medical records for statistical analysis. Follow-up was performed every 6 months with a clinical assessment along with magnetic resonance imaging (MRI) of the brain and audiometric evaluation in patients with serviceable hearing. Results The study included 34 patients (18 males and 16 females) with an average age of 45.5 years. The mean tumor volume was 10.9 cm 3 (standard deviation [SD], ± 0.83), with a median tumor dose of 12 Gy (interquartile range, 11.5-12) and a mean follow-up of 34.7 months (SD, ± 23.8). Tumor response was graded as regression in 50%, stable in 44.1%, and increase or GKRS failure in 2 cases (5.8%). Treatment failure was noted in five cases (14.7%), requiring microsurgical excision and a ventriculoperitoneal shunt post-GKRS. The tumor control rate for the cohort is 85.3%, with a facial preservation rate of 96% (24/25) and hearing loss in all (5/5), while three patients developed new-onset hypoesthesia. We noted that gait ataxia and involvement of cranial nerve V or VII at initial presentation were associated with GKRS failure in univariate analysis. Conclusion Microsurgery should remain the first-choice treatment option for large VSs. GKRS is a viable alternative with good tumor control and improved or stabilized cranial neuropathies with a low complication rate.
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Machine learning and artificial intelligence (AI) have become a part of our daily routine. There are very few of us who are not influenced by this technology. There are a lot of misconceptions about the scope, utility, and fallacies of AI. Digital neuropathology is an evolving area of research. The importance of digital image processing stems from the rapid gains in computer vision and image processing that have happened in the past decade thanks to advancements in deep learning (DL). The article attempts to present to the audience a simple presentation of the technology and attempts to provide a context-based understanding of the DL process for image processing. Also highlighted are current challenges and the roadblocks in adopting the technology in routine neuropathology.
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Inteligencia Artificial , Redes Neurales de la Computación , Humanos , Procesamiento de Imagen Asistido por Computador , Aprendizaje AutomáticoRESUMEN
INTRODUCTION: Chronic subdural hematoma (cSDH) is a disease of the elderly population. Incidence in paediatric population is relatively uncommon. Child abuse, birth trauma, coagulopathy and shunt surgeries represent major causes. Major impact of the disease on life of patient due to recurrence and repeat surgical procedure is significant, not to mention the burden on health care system. MATERIAL AND METHODS: We retrospectively reviewed our institute data for chronic sub-dural cases for the past 10 years (2008-2018) and collected data on the demography, clinical features, metabolic workup, mode of treatment, recurrence rates, predisposing factors, laterality, hematoma characteristics and factors associated with recurrence in all cases with less than or equal to 18 years of age. RESULTS: A total of 30 such cases were found in a period of 10 years (2008-2018). The mean patient age was 7.3 years (range 2 months-17 years), with 20 males (66.67%) and 10 females (33.33%). Raised intracranial pressure (n = 9) was the commonest presenting symptom in 30% of cases followed by seizures in 26.67% (n = 8). The previous shunt was the commonest predisposing factor seen in 43.33% (n = 13). cSDHs were unilateral in 56.67% cases (n = 17) and bilateral in 43.33% (n = 13). Burr hole craniostomy was done in 27 cases (90%), and conservative management was done in three cases (10%). Follow up was available for 27 cases (90%) with a mean follow up duration of 24 months. Recurrence rate was 30% (n = 9). Shunt surgery contributed to 77% of bilateral disease (p = 0.009). Child abuse was not reported in our series. CONCLUSION: Presence of paediatric cSDH is alarming, and the physician should be alerted to look for underlying cause and rule out child abuse. Detailed metabolic, skeletal workup is required. Treatment of primary pathology should be the goal as CSF diversion is not the solution to all problems, but can definitely be the cause of all the problems.
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Hematoma Subdural Crónico , Anciano , Causalidad , Niño , Drenaje/efectos adversos , Femenino , Hematoma Subdural Crónico/epidemiología , Hematoma Subdural Crónico/etiología , Hematoma Subdural Crónico/cirugía , Humanos , Incidencia , Lactante , Masculino , Estudios RetrospectivosRESUMEN
Seizure episodes are frequently observed for adults and children suffering from medically refractory epilepsy and the events remain debilitating unless treated with a more comprehensive approach. Ictal perfusion studies with single-photon emission computed tomography (SPECT) is one of the non invasive imaging modality that has been extensively used to adequately localize the seizure focus. Current practices include the tracer injection within a short time interval at the onset of seizure to generate desirable SPECT scan quality with accurate information on foci region. However, the onset of a seizure is a highly unpredictable event and also with added subclinical events, the overall procedure makes it difficult to administer the tracer manually within the ideal time frame.Hence a complete autonomous injection of radioactive tracer element without manual intervention is expected to offer a highly accurate epileptical focus region and aids in further management of the patient. Electroencephalogram (EEG) physiological signals in the preictal phase contain sufficient indicators to predict the seizure event. The proposed injection system works on the seizure prediction model from the EEG signals to release the dosage, making the system completely autonomous in action. The accuracy of the prediction model based on the publicly available seizure embedded EEG datasets was designed to achieve 94% accuracy, and the model was deployed on an edge system. The syringe based injection system was characterized to emulate dosage release action with minimum volumetric error, and low injection time, on predicting seizure Ictal event from the EEG signal. The proposed system is a step towards developing an autonomous injection system for epileptic neuroimaging applications in hospital settings.Clinical relevance- Autonomous injection of tracer dosage for obtaining accurate and high quality Ictal SPECT scan results is preferred over the manual operation in clinical and hospital residential settings as a part of pre-surgical evaluations. The EEG signal based early prediction of seizure ensures adequate time for radioactive tracer element to reach the brain cells and eventually helps to accurately localize the onset region of seizure in the brain. The EEG driven automated injection system for the noninvasive Ictal SPECT method is clinically important as a pre-surgical evaluation in MRI negative or discordant cases for further surgical actions.
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Electroencefalografía , Epilepsia , Encéfalo/diagnóstico por imagen , Epilepsia/diagnóstico por imagen , Humanos , Neuroimagen , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
Central nervous system high grade neuroepithelial tumor - BCOR altered is a newly defined entity which is characterised by internal tandem duplication (ITD) in exon 15 of BCOR. These tumors resemble high grade glioma histologically and exhibit BCOR immunopositivity. However, recently fusions of BCOR are also described in CNS lower grade gliomas, thus questioning the sensitivity and specificity of BCOR immunohistochemistry for identification of BCOR-ITD. We describe four cases of high grade neuroepithelial tumor with BCOR immunopositivity which were diagnosed over a period of one year at our institute. Amongst these, only one tumor revealed BCOR-ITD on sequencing. SATB2 immunopositivity which is a sensitive marker of BCOR-ITD, BCOR fusions and YWHAE fusions was noted in three out of four cases. Our study suggests that BCOR immunopositive CNS high grade tumors are molecularly heterogeneous and could harbour genetic alterations other than BCOR-ITD.
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Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Heterogeneidad Genética , Neoplasias Neuroepiteliales/genética , Neoplasias Neuroepiteliales/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Adolescente , Adulto , Biomarcadores de Tumor/metabolismo , Encéfalo/diagnóstico por imagen , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Preescolar , Imagen de Difusión por Resonancia Magnética , Exones/genética , Femenino , Fusión Génica , Humanos , Inmunohistoquímica , Masculino , Proteínas de Unión a la Región de Fijación a la Matriz/metabolismo , Estadificación de Neoplasias , Neoplasias Neuroepiteliales/diagnóstico por imagen , Neoplasias Neuroepiteliales/patología , Estudios Prospectivos , Secuencias Repetidas en Tándem/genética , Factores de Transcripción/metabolismoRESUMEN
INTRODUCTION: Cavitron Ultrasonic Surgical Aspirator (CUSA) is a technique used for the surgical treatment of tumors that aids the surgeon in highly selective tumor sampling with minimal injury to surrounding tissues. The utility of the tissue obtained from CUSA for histopathological diagnosis of central nervous system tumors is not as well-known as its surgical benefits. Even though a few studies have evaluated the diagnostic accuracy of CUSA specimen, these have dealt with very few cases. METHODOLOGY: In this study, we nil analysed 73 cases of CNS tumors (glial and non-glial) where CUSA specimen was available for histopathological examination and compared with findings on conventional samples as gold standard. RESULTS: Most frequent types of artefacts induced by CUSA included tissue breakdown resembling necrosis, empty spaces in tissues, and crush artefacts particularly in cellular tumors, that interfered with interpretation. CUSA samples were found optimal for diagnosis of non-glial tumors (45/73), (mainly mesenchymal), wherein the diagnostic utility was comparable to the conventional samples. Difficulties were encountered in glial neoplasms, medulloblastomas and meningiomas. In glial neoplasms (28/73), accurate grading was not possible (9/28, 32%) utilising CUSA samples alone as necrosis and mitosis were not represented. Similarly in meningiomas, mitosis and brain invasion, essential for grading, was not recognizable in CUSA samples. In medulloblastomas, extensive crush artefacts interfered with diagnosis and histological subtyping making it mandatory to examine conventional tissue samples and CUSA. Immunohistochemistry results were optimal with CUSA tissue, wherever performed. CONCLUSION: The greatest benefits of CUSA, is its ability to sample multiple areas enhancing the yield in heterogenous tumors like gliosarcomas and its utility in tumors at surgically inaccessible sites. As a policy, we recommend that it is beneficial that all surgically excised tissues including those from the CUSA bottle and suction be sent for histopathological analysis for optimising diagnostic accuracy.
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Neoplasias Meníngeas , Meningioma , Sistema Nervioso Central , Humanos , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Succión , UltrasonidoRESUMEN
Surface and needle-based electromyography signals are used as diagnostic markers for detecting neuromuscular disorders. Existing systems that are used to acquire these signals are usually expensive and invasive in practice. A novel 8 channel surface EMG (sEMG) acquisition system is designed and developed to acquire signals for various upper limb movements in order to evaluate the motor impairment. The real time sEMG signals are generated from the muscle fibre movements, originated solely from the upper limb physical actions. Intuitively, sEMG signals characterize different actions performed by the upper limb, which is considered apt for assessing the improvement for post stroke patients undergoing routine physical therapy activities. The system is designed and assembled in a view to make it affordable and modular for easier proliferation, and extendable to motor classifying applications. The system was validated by recording realtime sEMG data using six differential electrodes for various finger and wrist actions. The signals are filtered and processed to develop a machine learning (ML) model to classify upper limb actions, and other electronic systems are designed in the portable form around the patch electrodes. A classifier was trained to predict each action and the accuracy of the classifier was assessed across different usage of channels. The accuracy of the classifier was improved by optimizing the number of electrodes as well as the spatial position of these electrodes. The sEMG circuit designed has the capacity to characterize wrists, and finger movements. The improvement observed in the sEMG signals should benefit the physiotherapists to plan further protocols in the prescribed rehabilitation program.
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Enfermedades Neuromusculares , Rehabilitación de Accidente Cerebrovascular , Electromiografía , Humanos , Extremidad Superior , Articulación de la MuñecaRESUMEN
An upper limb anthropomimetic rehabilitation device has been designed for patients suffering from a neuromuscular disability. The developed device has been designed as a wearable device and attempts to supplement all known functions of the human hand and fingers. The actuation of individual joints of the hand and wrist has been implemented by using DC motors interfaced to a control system. A pulley system was adopted to ensure a low device profile with the aim of maximising functionality in the affected hand. Both actuators and the electronic assembly are sited in the forearm assembly for this purpose. The device is designed to fulfill multiple roles. At its simplest instance, it is designed as a device for providing resistance training in patients suffering from reversible neuromuscular weakness. The device also aims to provide support as an exoskeleton device in patients suffering from partial but permanent neuromuscular weakness. The measurement of finger and wrist bending in axial and radial directions were investigated by an array of potentiometers mounted around the wearable device covering different joints of the fingers and wrist, and were further analyzed to characterize the range of the device. The system is a composite device with diverse functions fulfilling all the requirements of an upperlimb orthotic device. The device is planned to be part of a comprehensive exoskeleton device for quadriparetic patients in the future.
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Mano , Extremidad Superior , Dedos , Humanos , Muñeca , Articulación de la MuñecaRESUMEN
BACKGROUND AND PURPOSE: Microcystic meningiomas (MM) are a distinctive, rare subtype of Grade I meningiomas with limited radiological descriptions. We intend to identify unique imaging phenotypes and seek radiopathological correlations. METHODS: Retrospective analysis of histopathologically proven MM was undertaken. Clinicodemographic profiles, imaging, and histopathological characteristics were recorded. Spearman rank correlations among radiological and pathological attributes were performed. RESULTS: Twenty-eight cases were analyzed (mean age = 45.5 years; M:F = 1:1.54; mean volume = 50.1 mL; supratentorial n = 27). Most lesions were markedly T2 hyperintense (higher than peritumoral brain edema-a unique finding) (89.3%) and showed invariable diffusion restriction, severe peritumoral brain edema (edema index >2 in 64.3%), a "storiform" pattern on T2-weighted images (T2WI) (75%), reticular pattern on postcontrast T1 (78.6%)/diffusion-weighted images (DWI) (65.4%), hyperperfusion, T1 hypointensity (84.6%), and absence of blooming on susceptibility-weighted image (80.9%). Storiform/reticular morphology correlated with large cysts on histopathology (ρ = .56; P = .005753). Lesion dimension positively correlated with reticular morphology on imaging (ρ = .59; P = .001173), higher flow voids (ρ = .65; P = .00027), and greater microcystic changes on histopathology (ρ = .51; P = .006778). Peritumoral brain edema was higher for lesions demonstrating greater angiomatous component (ρ = .46; P = .014451). CONCLUSIONS: We have elucidated varied neuroimaging features and highlighted pathological substrates of crucial imaging findings of MM. MM ought to be considered as an imaging possibility in an extra-axial lesion with a marked hypodensity on noncontrast computed tomography, markedly T2-hyperintense/T1-hypointense signal, and a storiform/reticular pattern on T2W/GdT1w//DWI.