Perilesional Edema Research Articles

Retrospective Study of Multimodality Imaging Features of Chondroblastoma

PurposeTo evaluate the multimodality imaging features of chondroblastoma.Materials and MethodsRetrospective analysis of imaging features of 52 cases of histopathologically proven chondroblastoma from 2010 to 2022 was performed. Radiographs were evaluated for lesion site, location, morphology, margins, matrix mineralization, cortical breach, periosteal reaction, eccentricity, and subarticular extension. Appearance on T1, T2 weighted and post-contrast T1 was evaluated on MRI, with analysis of peritumoral edema and joint effusion.ResultsMean patient age was 18 years (10–57 years) with male preponderance (M = 39; F = 13). 75% (n = 39) cases involved an unfused skeleton and 25% (n = 13) affected a mature skeleton. Appendicular skeleton was involved in 88.5% (n = 46) cases and axial skeleton was involved in 11.5% (n = 6) cases with all cases involving epiphysis/epiphyseal equivalent. Radiographically, all cases were well-defined geographic osteolytic lesions with a narrow zone of transition, thin sclerotic rim and lobulated [56% (n = 29)] or smooth [44% (n = 23)] margins. Matrix calcification appreciable in 62% (n = 32) cases was ‘fluffy/smudgy’. Chondroblastoma appeared isointense (83%, n = 43) on T1 MRI with characteristically low signal and hyperintense foci within (67%, n = 35) on T2-weighted images and post-contrast enhancement [heterogeneous lobular (88%, n = 46) or septal pattern (12%, n = 6)] with all barring three lesions showing perilesional edema. None of the cases of chondroblastoma in our study developed metastasis till last follow-up (mean: 71 months).ConclusionChondroblastoma has distinctive imaging appearance and is often unlike majority other cartilaginous benign lesions due to characteristic low T2 signal on MRI and associated exuberant perilesional edema.

Imaging Aspects of Cerebral Toxoplasmosis in Immunocompromised Patients

This is the first hypothesis to be raised, especially if the patient is not taking prophylactic treatment. Lesions are generally multiple, localized in the grey nuclei and cortico-subcortical regions (hematogenous dissemination), and may bleed spontaneously. The mass effect associated with peri lesional edema is often major, even if the lesion is small. Contrast is often annular, with the center of the lesion in hypersignal or T2 hyposignal, often remaining in diffusion hyposignal. After treatment, a scar in the form of a small, stable annular contrast pattern may persist for years.

HGG-43. DIFFUSE PEDIATRIC HIGH GRADE GLIOMA SUCCESSFULLY TREATED WITH MULTIMODAL THERAPY

Abstract BACKGROUND Pediatric high grade glioma (HGG) have a dismal prognosis despite aggressive treatment. In this report, we discuss a patient with HGG successfully treated with combination of resection, radiotherapy, chemotherapy, and biologic therapy. RESULTS An 8-year-old male presented with intermittent headaches, vomiting and fatigue. Imaging demonstrated four solid/cystic enhancing intra-axial lesions within the left cerebral hemisphere- two within the left frontotemporal region, one in the superior parietal region, and one in the temporal lobe, all with perilesional edema and resultant subfalcine herniation with midline shift. The patient underwent subtotal resection of the frontotemporal and parietal lesions. Histopathology was consistent with glioblastoma. Whole exome sequencing revealed alterations in TP53, ATRX, PTEN, TSC2 as well as subclonal mutation in NF1. The tumor was unable to be further classified by DNA methylation. However histopathologic and molecular findings support the diagnosis of diffuse pediatric-high grade glioma, H3-wildtype and IDH-wildtype. The patient received adjuvant 59.4 Gy focal proton therapy with concurrent temozolomide and maintenance chemotherapy with temozolomide and lomustine for 6 cycles. End of therapy imaging demonstrated complete resolution of all sites of disease. Due to high likelihood of recurrence, the patient was subsequently started on targeted therapy with everolimus and ribociclib which continue to be well tolerated without dose adjustments. The patient remains stable and without recurrence 2.5 years since diagnosis, and 15 months since initiation of biologic therapy. Additionally, the patient underwent testing for cancer predisposition which revealed presence of TP53 heterozygous mutation consistent with Li-Fraumeni syndrome. The patient remains without other malignancies on surveillance imaging per LFS guidelines. CONCLUSION Our case report illustrates the value of both chemotherapy and biologic therapy in treatment of HGG. In addition to this, it emphasizes the importance of germline testing for cancer predisposition in patients with high grade tumors.

Revisiting the Imaging Characteristics of Chondroblastoma with Special Emphasis on Prognosis and Radiological Predictors of Local Tumor Recurrence

Background Chondroblastoma is an uncommon benign cartilaginous tumor of young adults and adolescents, accounting for 1% of all bone tumors. We aim to analyze the imaging characteristics of pathologically proven chondroblastoma, measure the incidence rate of local recurrence of this tumor, and identify factors that may influence its local recurrence. Materials and methods The details of a total of 44 patients with pathologically proven chondroblastoma who underwent surgery and followed up by cross-sectional imaging between January 2006 and March 2021 at the KFSHRC in Riyadh were retrieved from our archive. All available modalities, including plain radiography, CT, and magnetic resonance imaging (MRI), performed at baseline and on follow-up were reviewed and correlated with the histopathological diagnosis. Recurrence was calculated from the date of surgery to the date of recurrence or the date of being lost to follow-up depending on the date of recurrence. The statistical software STATA was used to analyze the data. Results The tumor recurrence rate was 4.55% (n = 2). Similarly, the residual tumor rate was 4.55% (n = 2). No metastases were documented. The recurrence-free survival was 93.8% at the 722-day follow-up. More than 95% of lesions demonstrated typical imaging features including: a well-defined lobulated margin, intermediate-to-low signal on T2-weighted images, and perilesional edema. Conclusions This study emphasizes the imaging findings of chondroblastoma, which classically affects skeletally immature patients. Although imaging findings cannot be used to predict recurrence or survival, we obtained excellent prognosis following surgical treatment at our institution.

Solitary Tumefactive Demyelinating Lesions in Children: Clinical and Magnetic Resonance Imaging Features, Pathologic Characteristics, and Outcomes

BackgroundIsolated tumefactive demyelinating lesions (≥2 cm) may be difficult to distinguish from contrast-enhancing brain tumors, central nervous system infections, and (rarely) tissue dysgenesis, which may all occur with increased signal on T2-weighted images. Establishing an accurate diagnosis is essential for management, and we delineate our single-center experience. MethodsWe performed a retrospective review of medical records, imaging, and biopsy specimens for patients under 18 years presenting with isolated tumefactive demyelination over a 10-year period. ResultsTen children (eight female) met inclusion criteria, with a median age of 14.1 years. Lesions were most likely to involve the thalamus (six of 10), brainstem (five of 10), basal ganglia (four of 10), or corpus callosum (four of 10). Eighty percent had perilesional edema at presentation, and 60% had midline shift. Biopsies demonstrated demyelination with perivascular lymphocytic infiltration and axonal damage ranging from mild to severe. All patients were initially treated with high-dose corticosteroids, and eight of 10 required additional medical therapies such as intravenous immunoglobulin, plasmapheresis, cyclophosphamide, or rituximab. Increased intracranial pressure was managed aggressively with two of 10 patients requiring decompressive craniectomies. Clinical outcomes varied. ConclusionsSolitary tumefactive demyelinating lesions are rare, and aggressive management of inflammation and increased intracranial pressure is essential. Biopsy is helpful to evaluate for other diagnoses on the differential and maximize therapies. Treatment beyond initial therapy with corticosteroids is often required. Isolated tumefactive demyelinating lesions are uncommon; multicenter natural history studies are needed to better delineate differential diagnoses and optimal therapies.

Spinal Trauma Revealing a Metastatic Medullary Lesion: A Case Report

Introduction and Importance: Intramedullary spinal cord metastases (ISCM) are a rare and devastating complication of malignant disease with a poor prognosis. Prompt and accurate diagnosis is necessary for effective treatment, and magnetic resonance imaging (MRI) is the preferred imaging technique. In this article, a rare case of an ISCM presenting with motor weakness after trauma is described. Case Presentation: The patient showed progressive severe paraplegia and urinary retention, and a thoraco-abdomino-pelvic scan showed a mediastinal pulmonary process and mediastinal adenopathies with adrenal lesions. He was admitted and a total resection of the processus was performed. After surgery, the patient showed partial neurological improvement, but two weeks later, he had a consciousness impairment. A cerebral CT scan showed multiple round lesions, with perilesional edema, and the patient died one month later. Discussion: The article discusses the pathogenic mechanisms of ISCM and its diagnosis, treatment, and management, which are controversial due to the multitude of clinical circumstances and the lack of controlled studies on the efficacy of the different therapeutic approaches. Conclusion: In conclusion, this rare case of Intramedullary Spinal Cord Metastases (ISCM) offers several important take-away lessons for clinicians and researchers alike.

The Observation at Mean Oedema Index Variations with Location and Histological subtypes in Supratentorial WHO G-I Meningiomas

Background: The term meningioma is the noncommittal, all-encompassing name coined by Harvey Cushing for this tumor of meninges which is usually benign. The severity and variety of the peritumoral brain oedema may limit operative exposure and increase the difficulties of intraoperative procedures; however, its pathogenesis is not clearly documented. Several factors, such as tumor size, location and histology, mechanical compression of draining vein by the tumor have been proposed as mechanism of peritumoral brain oedema Aims: The objective of this study was to determination of mean oedema index in different locations and histological subtypes in patients with supratentorial WHO GI meningiomas Methods: The study was conducted in the Department of Neurosurgery, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from September, 2016 to March, 2018. This study was a cross sectional study. Data collection sheets were used to collect necessary information. Total 75 cases were selected consistent with inclusion and exclusion criteria. Tumor volume and localization and the presence of peritumoral brain oedema (PTBOe) were determined by MRI (Magnetic Resonance Image). All patients underwent microsurgical removal of tumor. Surgically resected meningiomas were classified histopathologically based on criteria of the new World Health Organization (WHO) classification. Regarding location and histological subtypes of tumor the study population were divided into 6 groups and 8 groups respectively.Statistical analyses were done by Statistical Packages for Social Sciences (SPSS-v.25). Results: A total 75 cases were selected consistent with inclusion and exclusion criteria from September, 2016 to March, 2018. Regarding location; the mean oedema index for each of the six groups was calculated and recorded. The F value was 5.97 and the P-value was 0.0001 which was less than 0.05. This result signifies that there was association between perilesional oedema in supratentorial meningioma to its location. So, Mean Oedema Index in Intracranial Supratentorial Meningiomas vary with its location. On the other hand, regarding histopathological subtypes, meningiomaswere divided into eight groups-the mean oedema index of each of the eight groups was calculated and recorded. The F value was 1.62 and P-value was 0.145 which was more than 0.05. This result signifies that there was no association between perilesional oedema in supratentorial meningioma to its histological subtypes. So mean oedema index in intracranial supratentorial meningiomas does not vary with its histological subtypes. Conclusion: Mean Oedema Index in Intracranial Supratentorial Meningiomas vary with its location but does not vary with histological subtypes Bang. J Neurosurgery 2023; 13(1): 10-13

Identification of predictive factors for better outcomes in LINAC-based radiation treatment for cerebral cavernous malformation

The effectiveness of radiation therapy in the treatment of cerebral cavernous malformations (CCM) remains debatable. However, numerous studies have shown a reduction in hemorrhage risk following radiotherapy for CCM. Therefore, herein, we share our experiences utilizing linear accelerator (LINAC)-based radiation for treating CCMs, with the aim of identifying the key factors influencing the therapeutic outcomes. We conducted a retrospective review of all patients with non-brainstem CCMs who underwent radiation treatment, as recorded in the NOVALIS registry at our institution. T2-weighted MR images were used for volumetric assessments using the iPlan radiotherapy planning software. To determine the independent predictors of nidus volume reduction and perilesional brain edema (PBE), we performed multivariate Cox regression analysis to calculate hazard ratios. Twenty patients with 31 non-brainstem CCMs were enrolled in this study. Analysis revealed age as an independent predictive factor for both nidus volume reduction and PBE after radiation treatment for CCM. Furthermore, a single fraction dose of 17 Gy or more was identified as an independent predictor of nidus volume decrease, while a single fraction dose of 18 Gy or more was found to be an independent risk factor for PBE in patients with CCM following LINAC-based radiation therapy. LINAC-based radiation therapy for non-brainstem CCMs with a single fraction radiation dose between 16.5 and 17.5 Gy, or a biologically equivalent dose of approximately 120 Gy, may be the most effective at reducing nidus volume and limiting side effects, particularly in patients under the age of 55 years. We further observed that the risk of PBE increased as the maximum radiation dose delivered to a 1 cc volume of the surrounding normal brain exceeded approximately 17.3 Gy. Therefore, we believe that calculating the D1cc of the normal brain may help to predict the occurrence of PBE when radiotherapy is administered to non-brainstem CCMs.

Predictors of Acute Cerebellar Bulge Prior to Posterior Fossa Lesion Resection

ObjectiveA cerebellar bulge prior to posterior fossa resection is an emergency condition during surgery. Intraoperative cerebellar bulging not only increases the difficulty of lesion resection but also brings additional postoperative complications. Currently, there are few systematic reports on this topic. The predictors of cerebellar bulge and how to effectively prevent intraoperative cerebellar bulge are discussed in this article. MethodsThe clinical and imaging data of 527 patients with posterior fossa lesions who underwent resection at our hospital were retrospectively collected and analyzed. Perioperative clinical and imaging data were assessed. Variables were analyzed using univariate and multivariate regression analyses. ResultsOverall, 10.4% (55/527) of patients had intraoperative acute bulges. Multivariate analysis revealed that age <60 years, BMI ≥24, lesion size ≥30 (mm), cerebellar tonsillar herniation and/or hydrocephalus, and perilesional edema (moderate-severe) were predictors of cerebellar bulging. Relief of the cerebellar bulge can be accomplished by excising the lesion, releasing cerebrospinal fluid, and removing the cerebellum (the outer 1/3). Obvious cerebellar-related complications occurred in 4 patients postoperatively, and the symptoms disappeared after 6 months of follow-up. ConclusionsCerebellar bulging during intraoperative posterior fossa resection deserves attention. Through the analysis of multiple factors related to cerebellar bulge, comprehensive evaluation and early intervention during the perioperative period are necessary. The incidence of cerebellar bulges can be reduced, and surgical complications related to cerebellar bulges can be avoided.

246 Algorithmic CT Scan Analysis for Prognosticating Brain Injury: A Preliminary Effort

INTRODUCTION: Predicting which trauma patients will progress to brain death is currently based on history, physical examination and radiographic findings. METHODS: 38 trauma subjects, 18 which progressed to brain death (BD), who suffered from high-velocity trauma with presumed diffuse axonal injury, cardiopulmonary/respiratory arrest, and/or found down were included. BLAST-CT was used to identify four lesion types: intraparenchymal hemorrhage, extra-axial hemorrhage, perilesional oedema, and intraventricular hemorrhage. Cerebrospinal fluid volumes were extracted using SimpleITK. These two sets of features were obtained from whole head CT scans and within 117 standardized brain atlas regions. Five ROC curves for classifying BD versus non-BD were generated using a support vector machine trained on (1) BLAST-CT (4 features), (2) Regional BLAST-CT (468 features), (3) Regional CSF volumes (117), (4) BLAST-CT + Regional CSF volumes (121 features), and (5) Regional BLAST-CT + Regional CSF volumes (585 features). RESULTS: For BLAST-CT alone, area under the curve (AUC), sensitivity, specificity, and accuracy in classifying BD were 0.7806, 61.11%, 95.00%, and 78.95% respectively. For regional BLAST CT, they were 0.7611, 55.56%, 100%, and 78.95% respectively. For regional CSF volume, they were 0.7056, 94.44%, 50.00%, and 71.05%. For BLAST-CT + regional CSF volumes, they were 0.8389, 94.44%, 65.00%, and 79.85%. For regional BLAST-CT + regional CSF volumes, they were 0.9083, 83.33%, 100%, 92.11%. CONCLUSIONS: Results indicate that the present model using regional BLAST-CT + regional CSF volumes is able to classify brain death with a large specificity, sensitivity, and accuracy above 90%. Given the clinical value of a tool to assist physicians in predicting progression to BD, additional prospective trials with larger samples and testing cohorts should be conducted.

A Pediatric Case Report: Dysembryoplastic Neuroepithelial Tumor or Ganglioglioma?

Dysembryoplastic neuroepithelial tumor (DNET) is a benign glioneuronal neoplasm that most frequently affects children and young adults. It can cause chronic seizures that are medically refractory. This tumor's cortical architecture and absence of a bulk effect or perilesional edema on radiographs are its defining features. The most typical manifestation of seizures is focal seizures with impaired awareness. Three DNET histologic subtypes have been identified. For either complicated or simple DNET types, histological detection of a distinct, particular glioneuronal component in brain tumor samples from individuals with medically refractory, chronic epilepsy serves as a diagnostic characteristic. We present one case of a child diagnosed with DNETs, who arrived at the hospital following seizures. The clinical, radiographic, histological, immunohistochemical, and molecular genetic characteristics of all three forms of DNETs as well as the differences between DNETs and gangliogliomas will be the main topics of this review.

Computed tomography-guided frame-based stereotactic brain biopsy of non-enhancing lesions using indirect evidence of target selection, technical consideration, and early clinical experience.

The objective was to study the effectiveness and diagnostic outcome of frame-based stereotactic brain biopsy (STB) done for contrast non-enhancing lesions using indirect evidence of target selection observed in a plain computed tomography (CT) scan of the head. Data of patients with contrast non-enhancing brain lesions who underwent STB are collected retrospectively from NIMHANS Bangalore, hospital neurosurgery database from January 2021 to March 2023. Those cases subjected to plain CT scans after fixing the stereotactic frame to the head were included in the study. A final histopathological report analysis of these cases was done to assess the diagnostic accuracy. A total of 27 such cases were biopsied. The mean age of subjects was 44.04 ± 17.812 years. Most subjects were in the age group 31-40 years (29.6%). About 55.6% were male and 44.4% were female. The most common site of biopsy was the frontal lobe. The most common indirect evidence on CT was perilesional edema at 33.3% and periventricular location at 33.3%, followed by intralesional calcification at 11.1%. Our diagnostic accuracy was 92.59%. The asymptomatic hemorrhage rate was 2%, and an increase in perilesional edema was seen in 2% of cases. Indirect targeting is a safe and intuitive method for biopsy of contrast non-enhancing lesions. Due consideration is to be given to various findings visible in non-contrast CT scans of the head as indirect evidence of target selection while performing frame-based STB of contrast non-enhancing lesions. This method will also be helpful in resource-limited centers, especially in low-income countries.

Antitubercular medications and levetiracetam-induced symmetric drug-related intertriginous and flexural exanthema

Symmetric drug-related intertriginous and flexural exanthema (SDRIFE) is a rare, distinctive cutaneous adverse reaction associated with various medications. Here, we present the case of a 48-year-old male, admitted with complaints of slurring of speech with a deviation of face with abnormal movements and posturing of hands and limbs and loss of consciousness for about 15 min. Magnetic resonance imaging (MRI) brain with angiography was done which was suggestive of a ring-enhancing lesion with perilesional edema hinting toward the possibility of tuberculoma. A contrast MRI brain was done which was suggestive of leptomeningeal and pachymeningeal left frontal region with perilesional edema suggestive of tuberculoma so the patient was started on antitubercular therapy and dexamethasone and levetiracetam. The patient developed redness over the lower abdomen which gradually progressed to involve the lower back, bilateral axilla, and upper back. Potential suspected drugs such as antitubercular therapy and levetiracetam were stopped and the patient improved. The patient was started on another antiepileptic injection lacosamide. Antitubercular therapy was started again, on starting isoniazid 75 mg the patient started developing itching again, which was managed by giving antihistaminic. This case report highlights the importance of recognizing and managing SDRIFE as a potential complication of combination drug therapy and the need for vigilant monitoring of patients receiving such medications.

Wait-and-scan: an alternative for curettage in atypical cartilaginous tumours of the long bones.

Due to its indolent clinical behaviour, the treatment paradigm of atypical cartilaginous tumours (ACTs) in the long bones is slowly shifting from intralesional resection (curettage) and local adjuvants, towards active surveillance through wait-and-scan follow-up. In this retrospective cohort study performed in a tertiary referral centre, we studied the natural behaviour of ACT lesions by active surveillance with MRI. Clinical symptoms were not considered in the surveillance programme. The aim of this study was to see whether active surveillance is safe regarding malignant degeneration and local progression. In total, 117 patients were evaluated with MRI assessing growth, cortical destruction, endosteal scalloping, periosteal reaction, relation to the cortex, and perilesional bone marrow oedema. Patients received up to six follow-up scans. At the time of the first follow-up MRI, 8% of the lesions showed growth (n = 9), 86% remained stable (101), and 6% decreased in size (n = 7). During the third follow-up, with a mean follow-up time of 60 months (SD 23), 24 patients were scanned, of whom 13% had lesions that had grown and 13% lesions that had decreased in size. After 96 months (SD 37), at the sixth follow-up MRI, 100% of the lesions remained stable. None of the lesions showed malignant progression and although some lesions grew in size (mean 1 mm (SD 0.8)), no malignant progression occurred. We conclude that active surveillance with MRI is safe for ACTs in the long bones in the short- and mid-term follow-up.

SOFT TISSUE MASS AND ELECTRICAL DISCHARGE: WHATS INVOLVED?

An 11-year-old girl presented with a gradually evolving, painful arm mass over 6 months. Clinical examination revealed a 4cm soft mass causing electric discharge pain on percussion, without signs of inflammation. Ultrasound depicted a well-defined, heterogeneous mass connected to the median nerve with moderate vascularization. Subsequent MRI showed an eccentric fusiform mass within the median nerve, exhibiting a muscle-like signal on T1-weighted images, a heterogeneous signal on STIR, and enhancement after contrast. No bony destruction or muscle invasion was observed. Peripheral nerve sheath tumors, including neurofibromas and schwannomas, were suspected. MRI played a crucial role, revealing characteristic signs like split fat, target, and fascicular signs, aiding in distinguishing between benign and malignant lesions. Intra-tumoral changes, like cystic degeneration seen in schwannomas, were noted. Malignant tumors, such as MPNSTs, showed distinct features like increased size, heterogeneous appearance, perilesional edema, and bony destruction. In summary, the patients arm mass, initially detected through ultrasound and further characterized by MRI, raised concern for peripheral nerve sheath tumors, highlighting the significance of imaging in diagnosing and distinguishing these lesions.

Supplementary Motor Area Syndrome After Resection of a Dominant Hemisphere Parasagittal Meningioma: A Case Report

BACKGROUND AND IMPORTANCE: Supplementary motor area (SMA) syndrome is a common, transient postoperative complication of intra-axial tumor resections involving the SMA and posterior cingulate gyrus. It is also reported as a rare complication of resecting extra-axial lesions. Meningiomas represent the most common, nonmalignant primary central nervous system tumor in adults, which present most commonly in parasagittal locations. Resection of dominant hemisphere parasagittal meningiomas overlying or infiltrating into the SMA region carry a recognizable risk for developing SMA syndrome postoperatively. CLINICAL PRESENTATION: We present a 58-year-old woman with intermittent headaches and concern for new-onset seizures. MRI demonstrated an extra-axial mass involving the left frontal convexity and SMA region with homogenous postcontrast enhancement. There was radiographic involvement of the superior sagittal sinus and inner table of the skull. Fluid-attenuated recovery signal and perilesional vasogenic edema were also noted. The imaging findings favored a parasagittal meningioma, and surgical resection was performed. Arachnoid invasion and pial infiltration of the tumor over the SMA were evident during the operation. CONCLUSION: A detailed understanding of the functional neuroanatomy and clinical pathophysiology of eloquent cortical regions is important for preoperative planning and patient counseling. Surgical resection of lesions in such areas can result in rare complications uniquely implicated in specific patient subsets. Recognizing these patients in the preoperative setting is imperative for proper counseling of patients and families.

Multiple Intracranial Tuberculomas In Immunocompetent Patient: An Uncommon Primary Manifestation Of Central Nervous System Tuberculosis (CNS TB)

Tuberculosis (TB) is a serious yet potentially-curable health issue among most developing countries including Pakistan. We report the case of an immunocompetent patient having multiple intracranial tuberculomas without evidence of meningitis which is an uncommon manifestation of CNS tuberculosis. A 50-year old man presented with 5 episodes of tonic-clonic generalized fits for 1 day, right sided body weakness for 2 weeks, generalized headaches and intermittent low-grade fever for 1 month. No contact or past history of tuberculosis was reported. On neurologic examination, there was hypertonia, exaggerated deep tendon reflexes and power of 3/5 in both right upper limb and right lower limb with a right plantar extensor response. CT scan (Brain) showed hyperdense areas in left frontal and temporal lobes with surrounding vasogenic edema. ESR was raised at 86 mm/hour. CSF analysis demonstratedRBC 0 cells/uL, WBC 783 cells/uL with 100% lymphocytes, Glucose 39 mg/dl andProtein 81 mg/dl with negative organism microscopy onAFB and Giemsa staining. However, CSF was positive for GeneXpert-PCR-MTB but drug resistance was not detected to rifampicin. Brain MRI with FLAIR demonstrated multiple disseminated, rim enhancing lesions with perilesional edema in bilateral cerebral hemispheres, thalami, left basal ganglia, medulla oblangata and cerebellum having no meningeal enhancement. Workup for immune-suppression was normal. A diagnosis of multiple intracranial tuberculomas was established and Anti-tubercular therapy was commenced. He was asymptomatic and taking ATT with good compliance having no adverse affects by 6-week follow up.

Infectious Lesion Simulating Malignant Neoplasm. Clinical Case and Literature Review

The extrapulmonary manifestations of tuberculosis (TBC) that affect the Central Nervous System (CNS), by hematogenous dissemination, are an infrequent entity. Intracranial tuberculomas are the least common form of tuberculosis in CNS. Represent a granulomatous inflammatory process with cerebral involvement. The prognosis is related to the early diagnosis, the degree of surgical resection and the complemen-tary treatment with antituberculous drugs. We describe an infrequent clinical case of cerebral tuberculoma that simulated a malignant neoplasm, and also performed a literature review. A clinical case about a 31-year-old female with no relevant medical history. She described a sud-denly diplopia, without previous trauma. The patient was evaluated by Ophthalmology, which iden-tified papillary edema, with no other alterations. In this context was performed a Brain CT/MRI, which showed an intra-axial, left frontobasal lesion with perilesional edema, ring contrast enhancement and a hypodense/hypointense central area. Spectroscopy showed a reduction in n-acetylaspartate (NAA) with a peak in creatine and choline, suggestive of a malignant tumor. The patient underwent surgery, having performed a frontal left craniotomy and complete excision of a nodular, capsulated, avascular lesion with a spongy consistency. Subsequently, the histological diagnosis of tuberculoma was confirmed. We describe an infrequent clinical case of cerebral tuberculoma which, due to the characteristics presented in the preoperative studies, was suggestive of a malignant tumor that was not confirmed, which is the particularity of this case. The patient presents a good clinical and imaging evolution during the follow-up period.

DNAR-10. HETEROGENEOUS MGMT PROMOTER METHYLATION IN A MULTIFOCAL GLIOBLASTOMA: A CASE REPORT

Abstract MGMT promoter methylation status is an important predictive biomarker for treatment response in glioblastoma. MGMT unmethylated glioblastoma has elevated levels of MGMT which ultimately leads to chemoresistance. Clinicians consider the MGMT methylation status when treatment recommendations are given, and clinical trials use this marker for the selection of a homogenous group of glioblastoma patients based on prognosis. Here, we present a case of multifocal glioblastoma with heterogeneous MGMT methylation status. A 56-year-old male presented with left leg weakness for 2 months and left arm weakness for 1 month. Imaging revealed a calcified, rim enhancing right temporoparietal cystic lesion and a heterogeneously enhancing right parietal mass. Perilesional edema surrounded and connected the two lesions. The patient underwent gross total resection of the parietal mass and pathology revealed a WHO grade 4 glioblastoma, IDH wildtype, unmethylated tumor. Postoperatively, the patient was neurologically intact. He completed a 6-week long course of concomitant chemoradiation without any significant side effects. Two weeks later the patient developed rapidly worsening headaches, nausea, vomiting, dizziness, and left side weakness. Imaging revealed significant enlargement of the previously unresected temporoparietal cystic lesion with marked increase in surrounding edema and a 2-3 mm right to left midline shift. Patient underwent craniotomy with cyst drainage and tumor resection of the right cystic temporoparietal lesion, demonstrating a WHO grade 4 glioblastoma, IDH wildtype, methylated tumor. Post-operatively the patient was again neurologically intact and started adjuvant temozolomide. MGMT methylation status of glioblastoma can alter recommendations for chemotherapy with temozolomide. MGMT methylation status might vary in distinct parts of the tumor as molecular heterogeneity is a hallmark of glioblastoma. This heterogeneity should be considered by clinicians when treatments are recommended and by clinical trials for glioblastoma patients, especially when multifocal lesions have a distinct radiographic appearance.

Influence of clinical and tumor-specific factors on the resting motor threshold in navigated transcranial magnetic stimulation

ObjectivePreoperative non-invasive mapping of motor function with navigated transcranial magnetic stimulation (nTMS) has become a widely used diagnostic procedure. Determination of the patient-individual resting motor threshold (rMT) is of great importance to achieve reliable results when conducting nTMS motor mapping. Factors which contribute to differences in rMT of brain tumor patients have not been fully investigated. MethodsWe included adult patients with all types of de novo and recurrent intracranial lesions, suspicious for intra-axial brain tumors. The outcome measure was the rMT of the upper extremity, defined as the stimulation intensity eliciting motor evoked potentials with amplitudes greater than 50µV in 50 % of applied stimulations. ResultsEighty nTMS examinations in 75 patients (37.5 % female) aged 57.9 ± 14.9 years were evaluated. In non-parametric testing, rMT values were higher in patients with upper extremity paresis (p = 0.024) and lower in patients with high grade gliomas (HGG) (p = 0.001). rMT inversely correlated with patient age (rs=-0.28, p = 0.013) and edema volume (rs=-0.28, p = 0.012) In regression analysis, infiltration of the precentral gyrus (p<0.001) increased rMT values. Values of rMT were reduced in high grade gliomas (p<0.001), in patients taking Levetiracetam (p = 0.019) and if perilesional edema infiltrated motor eloquent brain (p<0.001). Subgroup analyses of glioma patients revealed similar results. Values of rMT did not differ between hand and forearm muscles. ConclusionMost factors confounding rMT in our study were specific to the lesion. These factors contributed to the variability in cortical excitability and must be considered in clinical work with nTMS to achieve reliable results with nTMS motor mapping.