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1.
Can J Neurol Sci ; : 1-21, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38777802

RESUMO

The innate and adaptive immune systems are critical in defense against pathogens and ensuring homeostasis. The central nervous system (CNS) was initially considered to be impermeable to immune cells due to the blood-brain barrier. However, this has now been debunked, with modern research delineating immune cell trafficking within the CNS, ensuring constant immune surveillance. However, these defenses may be breached in infections, which trigger an inflammatory cascade causing tissue damage. In addition, autoimmune conditions and genetic mutations may also lead to sustained proinflammatory molecule release causing significant CNS damage. Ensuing brain injury from most immune triggers is varied but may be associated with common patterns by virtue of a shared immune driver. MRI plays an important role in identifying these conditions and further enables understanding of their pathophysiology as well as their spatial predilection in the brain. In this review, we discuss basic immunology, the major CNS barriers to infections as well as the current understanding of selected pediatric infections and inflammatory processes.

2.
J Neurooncol ; 164(3): 597-605, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37707752

RESUMO

PURPOSE: To investigate the changes in apparent diffusion coefficient (ADC) within incrementally-increased margins beyond the gross tumor volume (GTV) on post-operative radiation planning MRI and their prognostic utility in glioblastoma. METHODS: Radiation planning MRIs of adult patients with newly diagnosed glioblastoma from 2017 to 2020 were assessed. The ADC values were normalized to contralateral normal white matter (nADC). Using 1 mm isotropic incremental margin increases from the GTV, the nADC values were calculated at each increment. Age, ECOG performance status, extent of resection and MGMT promoter methylation status were obtained from medical records. Using univariate and multivariable Cox regression analysis, association of nADC to progression-free and overall survival (PFS, OS) was assessed at each increment. RESULTS: Seventy consecutive patients with mean age of 53.6 ± 10.3 years, were evaluated. The MGMT promoter was methylated in 31 (44.3%), unmethylated in 36 (51.6%) and unknown in 3 (4.3%) patients. 11 (16%) underwent biopsy, 41 (44%) subtotal resection and 18 (26%) gross total resection. For each 1 mm increase in distance from GTV, the nADC decreased by 0.16% (p < 0.0001). At 1-5 mm increment, the nADC was associated with OS (p < 0.01). From 6 to 11 mm increment the nADC was associated with OS with the p-value gradually increasing from 0.018 to 0.046. nADC was not associated with PFS. CONCLUSION: The nADC values at 1-11 mm increments from the GTV margin were associated with OS. Future prospective multicenter studies are needed to validate the findings and to pave the way for the utilization of ADC for margin reduction in radiation planning.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Adulto , Humanos , Pessoa de Meia-Idade , Glioblastoma/diagnóstico por imagem , Glioblastoma/genética , Glioblastoma/radioterapia , Carga Tumoral , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Imagem de Difusão por Ressonância Magnética , Prognóstico , Estudos Retrospectivos
3.
Radiographics ; 43(4): e220102, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36893052

RESUMO

Sensorineural hearing loss results from abnormalities that affect the hair cells of the membranous labyrinth, inner ear malformations, and conditions affecting the auditory pathway from the cochlear nerve to the processing centers of the brain. Cochlear implantation is increasingly being performed for hearing rehabilitation owing to expanding indications and a growing number of children and adults with sensorineural hearing loss. An adequate understanding of the temporal bone anatomy and diseases that affect the inner ear is paramount for alerting the operating surgeon about variants and imaging findings that can influence the surgical technique, affect the choice of cochlear implant and electrode type, and help avoid inadvertent complications. In this article, imaging protocols for sensorineural hearing loss and the normal inner ear anatomy are reviewed, with a brief description of cochlear implant devices and surgical techniques. In addition, congenital inner ear malformations and acquired causes of sensorineural hearing loss are discussed, with a focus on imaging findings that may affect surgical planning and outcomes. The anatomic factors and variations that are associated with surgical challenges and may predispose patients to periprocedural complications also are highlighted. © RSNA, 2023 Quiz questions for this article are available through the Online Learning Center. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.


Assuntos
Implante Coclear , Implantes Cocleares , Orelha Interna , Perda Auditiva Neurossensorial , Criança , Adulto , Humanos , Implante Coclear/efeitos adversos , Implante Coclear/métodos , Perda Auditiva Neurossensorial/diagnóstico por imagem , Perda Auditiva Neurossensorial/cirurgia , Perda Auditiva Neurossensorial/etiologia , Orelha Interna/anormalidades , Orelha Interna/cirurgia , Implantes Cocleares/efeitos adversos , Osso Temporal/anatomia & histologia
4.
Can Assoc Radiol J ; 74(4): 713-722, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37070854

RESUMO

PURPOSE: Rapid identification of hematoma expansion (HE) risk at baseline is a priority in intracerebral hemorrhage (ICH) patients and may impact clinical decision making. Predictive scores using clinical features and Non-Contract Computed Tomography (NCCT)-based features exist, however, the extent to which each feature set contributes to identification is limited. This paper aims to investigate the relative value of clinical, radiological, and radiomics features in HE prediction. METHODS: Original data was retrospectively obtained from three major prospective clinical trials ["Spot Sign" Selection of Intracerebral Hemorrhage to Guide Hemostatic Therapy (SPOTLIGHT)NCT01359202; The Spot Sign for Predicting and Treating ICH Growth Study (STOP-IT)NCT00810888] Patients baseline and follow-up scans following ICH were included. Clinical, NCCT radiological, and radiomics features were extracted, and multivariate modeling was conducted on each feature set. RESULTS: 317 patients from 38 sites met inclusion criteria. Warfarin use (p=0.001) and GCS score (p=0.046) were significant clinical predictors of HE. The best performing model for HE prediction included clinical, radiological, and radiomic features with an area under the curve (AUC) of 87.7%. NCCT radiological features improved upon clinical benchmark model AUC by 6.5% and a clinical & radiomic combination model by 6.4%. Addition of radiomics features improved goodness of fit of both clinical (p=0.012) and clinical & NCCT radiological (p=0.007) models, with marginal improvements on AUC. Inclusion of NCCT radiological signs was best for ruling out HE whereas the radiomic features were best for ruling in HE. CONCLUSION: NCCT-based radiological and radiomics features can improve HE prediction when added to clinical features.


Assuntos
Hemorragia Cerebral , Hematoma , Humanos , Estudos Retrospectivos , Estudos Prospectivos , Hemorragia Cerebral/diagnóstico por imagem , Hematoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X
5.
Neuroradiology ; 64(12): 2285-2293, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35551423

RESUMO

INTRODUCTION: The study aims to assess the correlation and association between calcium burden and luminal stenosis in the vertebrobasilar circulation. METHODS: We evaluated 166 patients [mean age, 79.8 ± 8.8 (SD) with 93 males] with stroke symptoms. The calcification patterns were assessed on non-contrast CT (NCCT); quantitative calcium burden [Agatston-Janowitz (AJ) calcium score, volume, and mass] on the initial non-contrast phase of CT perfusion (CTP); and the qualitative and quantitative luminal stenosis on CT angiography (CTA) studies. We calculated the correlation coefficient and association between measures of calcium burden and luminal stenosis. RESULTS: Two hundred twenty-eight of 498 arteries (45.8%) had detectable calcification on NCCT and measurable stenosis in 169 of 498 arteries (33.9%) on CTA. We found a moderate correlation between qualitative calcium burden and qualitative (0.51 for R1 and 0.62 for R2, p < 0.01) as well as quantitative luminal stenosis (0.67 for R1 and 0.69 for R2, p < 0.01). There was a moderate correlation of AJ score (0.66), volume (0.68), and mass of calcification (0.60, p < 0.01) with luminal stenosis measurements. The quantitative calcium burden and luminal stenosis showed statistically significant differences between different qualitative categories of calcium burden (p < 0.001 in both readers). However, severe stenosis was not seen even with the advanced circumferential wall calcification (mean stenosis of 35.3-40.7%). CONCLUSION: Our study showed a moderate correlation between higher burden of vascular calcification and the degree of luminal stenosis. However, higher calcium burden and circumferential wall calcification were not associated with severe luminal stenosis.


Assuntos
Acidente Vascular Cerebral , Calcificação Vascular , Masculino , Humanos , Idoso , Idoso de 80 Anos ou mais , Cálcio , Calcificação Vascular/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Angiografia por Tomografia Computadorizada , Constrição Patológica , Valor Preditivo dos Testes
6.
Neurol Sci ; 43(11): 6461-6470, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35852658

RESUMO

PURPOSE: Assess factors in posterior reversible encephalopathy syndrome (PRES) related to intensive care unit (ICU) admissions, mechanical ventilation, and length of stay (LoS). METHODS: Retrospectively, we collected clinical, biochemical, and imaging data of PRES patients. MRI studies were assessed for imaging severity, and complications, including restricted diffusion and hemorrhage. Univariate and multivariate regression analyses were performed for factors associated with ICU admission, mechanical ventilation, and LoS. We assessed for association between clinical and biochemical factors and imaging severity grading systems and complications. RESULTS: We had 57 subjects with mean ± SD age of 56.3 ± 14.5 years and 68.3% were females. In 60 cases, 36.7% had hypertension, 23.3% had chronic renal disease, 18.3% had sepsis, 16.7% were on active chemotherapy, 10% underwent hematopoietic stem cell transplantation (HSCT), 10% with active cancer, 6.7% were eclampsia/preeclampsia, and 1.7% had radiotherapy. We had 17 (26.6%) grade 1, 26 (46.8%) grade 2, 17 (26.6%) grade 3 PRES based on vasogenic edema extent, and 28 (46.7%) severe PRES (≥ 5 areas) cases. 19 (31.7%) had restricted diffusion with hemorrhage in 19 (31.7%) cases. On multivariate analysis, ICU admissions showed significant association with hypertension (OR = 5.57, 95% CI: 0.96-32.23; p = 0.05), and raised INR (OR = 119, 95% CI: 1.1-1244.3; p = 0.04); LoS with HSCT, mean arterial pressure (MAP), intraparenchymal hematoma, and sepsis; and extent of vasogenic edema with restricted diffusion (OR = 4.31, 95% CI: 1.5-12.33; p < 0.01). CONCLUSION: In summary, PRES with hypertension and elevated INR are associated with ICU admissions. HSCT, MAP, intraparenchymal hematoma, and sepsis correlated with LoS. Imaging severity grading based on vasogenic edema extent may be better due to association with restricted diffusion.


Assuntos
Hipertensão , Síndrome da Leucoencefalopatia Posterior , Sepse , Gravidez , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Masculino , Síndrome da Leucoencefalopatia Posterior/etiologia , Síndrome da Leucoencefalopatia Posterior/complicações , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Hipertensão/complicações , Hospitalização , Sepse/complicações , Sepse/diagnóstico por imagem , Hematoma/complicações
7.
Can Assoc Radiol J ; 73(4): 655-671, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35253470

RESUMO

The petrous apex (PA) is involved in a myriad of pathological conditions, some of which are exclusive in children. Diagnosis may be difficult due to vague clinical presentation, and local examination is challenging owing to its inaccessible location. This is further complicated by multiple unfused sutures and ongoing PA pneumatization in children. Cross-sectional imaging is vital for the evaluation of the PA lesions, due to their precarious location and proximity to the major neurovascular structures. Several classification systems have been proposed for these lesions based on their site of origin, solid or cystic appearance, surgical or non-surgical (no touch lesions) management, and benign or malignant nature. In this article, we emphasize the distinctive role of different cross-sectional imaging modalities in the diagnosis of pediatric PA lesions, with special attention to normal variants that should not be mistaken for pathology. We also propose a radiological classification and algorithmic approach to aid in the precise diagnosis and facilitate appropriate management of the various PA lesions in children.


Assuntos
Osso Petroso , Tomografia Computadorizada por Raios X , Algoritmos , Criança , Humanos , Imageamento por Ressonância Magnética/métodos , Osso Petroso/diagnóstico por imagem , Osso Petroso/patologia , Radiografia , Tomografia Computadorizada por Raios X/métodos
9.
J Neuroradiol ; 44(5): 319-325, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28602499

RESUMO

PURPOSE: To assess the significance of association and possible correlation between hemorrhage, cytotoxic edema, blood pressure and imaging severity in posterior reversible encephalopathy syndrome (PRES). MATERIALS AND METHODS: This retrospective study included the medical and imaging records of 35 consecutive patients with PRES. The clinical data analysis included the highest recorded blood pressure (BP) on the day of the ictus, MRI including spin-echo echo planar diffusion-weighted imaging (DWI), susceptibility weighted angiography (SWAN) and conventional sequences. The presence of hemorrhage and cytotoxic edema was evaluated for the significance of correlation and association with each other and with blood pressure and imaging severity. RESULTS: On MR imaging, hemorrhage was found in 25.7%, and cytotoxic edema in 20% of patients. There was no statistically significant association of hemorrhage (P=0.403) and cytotoxic edema (P=0.162) with BP in contrast to significant association of hemorrhage (P<0.001) and cytotoxic edema (P=0.011) with imaging severity and with each other (P=0.002). There was a significant correlation of hemorrhage (Cramer's V - 0.672) and cytotoxic edema (Cramer's V - 0.506) with imaging severity and with each other (Cramer's V - 0.523). CONCLUSION: The extent of imaging severity in PRES showed significant association and correlation with hemorrhage and cytotoxic edema. There was no statistically significant association of blood pressure with imaging severity, hemorrhage, and cytotoxic edema. Further prospective studies are needed to elucidate the pathophysiological mechanisms and their correlation with imaging findings in PRES.


Assuntos
Angiografia Cerebral/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Adulto , Idoso , Edema Encefálico/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Imagem Ecoplanar , Feminino , Humanos , Hipertensão Intracraniana/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença
10.
Pol J Radiol ; 82: 279-282, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28607626

RESUMO

BACKGROUND: Mid-esophageal region is an uncommon location of esophageal diverticula, a condition usually diagnosed in elderly individuals. CASE REPORT: We report a case of an elderly male with incidental finding of mediastinal lesion, which was initially thought to be an aortic aneurysm. Further evaluation demonstrated a mid-esophageal diverticulum at the level of the carina. We present patient's medical history and imaging, followed by a discussion on symptoms and management. CONCLUSIONS: Knowledge of benign conditions that might mimic a mediastinal vascular pathology is important for therapeutic and prognostic reasons, as they are often managed conservatively.

11.
Head Neck ; 46(3): 561-570, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38116716

RESUMO

PURPOSE: To evaluate the association of primary tumor volume (TV) with overall survival (OS) and disease-free survival (DFS) in T3 N0-3M0 supraglottic cancers treated with intensity-modulated radiotherapy (IMRT). METHODS: This was a retrospective cohort study involving 239 patients diagnosed with T3 N0-3M0 supraglottic cancers between 2002 and 2018 from seven regional cancer centers in Canada. Clinical data were obtained from the patient records. Supraglottic TV was measured by neuroradiologists on diagnostic imaging. Kaplan-Meier method was used for survival probabilities, and a restricted cubic spline Cox proportional hazards regression analysis was used to analyze TV associations with OS and DFS. RESULTS: Mean (SD) of participants was 65.2 (9.4) years; 176 (73.6%) participants were male. 90 (38%) were N0, and 151 (64%) received concurrent systemic therapy. Mean TV (SD) was 11.37 (12.11) cm3 . With mean follow up (SD) of 3.28 (2.60) years, 2-year OS was 72.7% (95% CI 66.9%-78.9%) and DFS was 53.6% (47.4%-60.6%). Increasing TV was associated (per cm3 increase) with worse OS (HR, 1.01, 95% CI 1.00-1.02, p < 0.01) and DFS (HR, 1.01, 95% CI 1.00-1.02, p = 0.02). CONCLUSIONS: Increasing primary tumor volume is associated with worse OS and DFS in T3 supraglottic cancers treated with IMRT, with no clear threshold. The findings suggest that patients with larger tumors and poor baseline laryngeal function may benefit from upfront laryngectomy with adjuvant radiotherapy.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Laríngeas , Humanos , Masculino , Feminino , Estudos Retrospectivos , Carcinoma de Células Escamosas/patologia , Carga Tumoral , Canadá , Neoplasias Laríngeas/patologia , Intervalo Livre de Doença , Estadiamento de Neoplasias
12.
Clin Neuroradiol ; 33(1): 5-20, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35750917

RESUMO

Cerebral vasculitis is increasingly recognized as a common cause of pediatric arterial stroke. It can present with focal neurological deficits, psychiatric manifestations, seizures, and encephalopathy. The etiopathogenesis of childhood cerebral vasculitis (CCV) is multifactorial, making an inclusive classification challenging. In this review, we describe the common and uncommon CCV with a comprehensive discussion of etiopathogenesis, the role of various imaging modalities, and advanced techniques in diagnosing CCV. We also highlight the implications of relevant clinical, laboratory, and genetic findings to reach the final diagnosis. Based on the clinicoradiological findings, a stepwise diagnostic approach is proposed to facilitate CCV diagnosis and rule out potential mimics. Identification of key clinical manifestations, pertinent blood and cerebrospinal fluid results, and evaluation of central nervous system vessels for common and disease-specific findings will be emphasized. We discuss the role of magnetic resonance imaging, MR angiography, and vessel wall imaging as the imaging investigation of choice, and reservation of catheter angiography as a problem-solving tool. We emphasize the utility of brain and leptomeningeal biopsy for diagnosis and exclusion of imitators and masqueraders.


Assuntos
Acidente Vascular Cerebral , Vasculite do Sistema Nervoso Central , Humanos , Criança , Vasculite do Sistema Nervoso Central/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Acidente Vascular Cerebral/etiologia , Angiografia Cerebral
13.
J Biomol Struct Dyn ; 41(22): 12610-12619, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36651083

RESUMO

Pseudomonas aeruginosa is one of the leading opportunistic pathogens that causes nosocomial pneumonia and mostly in people with cystic fibrosis. In the present study, an in-silicoapproach was adopted to identify the novel drug target against Pseudomonas aeruginosa by employing subtractive genomics and molecular docking studies. Each step in the subtractive genomics scrutinized the bacterial proteome and determined a potential drug target against Pseudomonas aeruginosa. 71 essential proteins were obtained from the subcellular localization method that resides in the extracellular region. Metabolic pathways were studied to elucidate the unique pathways where the involvement of proteins present in the pathogen was predicted and a total of 6 unique pathways were determined. By, Genome mining of the source organism Paenibacillusehimensis, 9 ligands were obtained. The molecular docking analysis between the binding site of target protein NDK and ligands was carried out by employing the AutoDock Vina tool. Based on the highest binding affinity, Paenibactin, AnabaenopeptinNZ857 and Nostamide A complex with NDK protein with a lower binding energy of -7.5 kcal/mol, -7.4and -7.2 kcal/molrespectively were considered for the simulation studies. Molecular dynamics simulation studies showed the ligand in complex with protein was highly stable and rigid for a duration of 150 ns. For Paenibactin, AnabaenopeptinNZ857 and Nostamide Acomplex with protein, RMSD plot showed a deviation of ∼0.2-0.3 nm till ∼30ns/50 ns-110ns and further stabilized. The radius of the gyration plot clearly showed that the values stayed at ∼1.45 nm- 1.55 nm showing compactness and stability. The SASA stayed at the range ∼80nm2 and at least one total number of hydrogen bonds was shown throughout the 150 ns simulation for all three possible ligand-protein complexes. In the RMSF plot, the maximum fluctuation was ranged from ∼0.4-0.42 nm at the range between ∼57ns-60ns.The Paenibactin, AnabaenopeptinNZ857 and Nostamide A complex with NDK protein showed a stable, rigid and compact interaction throughout the simulation of duration 150 ns.Communicated by Ramaswamy H. Sarma.


Assuntos
Núcleosídeo-Difosfato Quinase , Pseudomonas aeruginosa , Humanos , Simulação de Acoplamento Molecular , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Núcleosídeo-Difosfato Quinase/genética , Ligantes , Sítios de Ligação , Simulação de Dinâmica Molecular
14.
JAMA Otolaryngol Head Neck Surg ; 149(2): 103-109, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36480193

RESUMO

Importance: The association of primary tumor volume with outcomes in T3 glottic cancers treated with radiotherapy with concurrent chemotherapy remains unclear, with some evidence suggesting worse locoregional control in larger tumors. Objective: To evaluate the association of primary tumor volume with oncologic outcomes in patients with T3 N0-N3 M0 glottic cancer treated with primary (chemo)radiotherapy in a large multi-institutional study. Design, Setting, and Participants: This multi-institutional retrospective cohort study involved 7 Canadian cancer centers from 2002 to 2018. Tumor volume was measured by expert neuroradiologists on diagnostic imaging. Clinical and outcome data were extracted from electronic medical records. Overall survival (OS) and disease-free survival (DFS) outcomes were assessed with marginal Cox regression. Laryngectomy-free survival (LFS) was modeled as a secondary analysis. Patients diagnosed with cT3 N0-N3 M0 glottic cancers from 2002 to 2018 and treated with curative intent intensity-modulated radiotherapy (IMRT) with or without chemotherapy. Overall, 319 patients met study inclusion criteria. Exposures: Tumor volume as measured on diagnostic imaging by expert neuroradiologists. Main Outcomes and Measures: Primary outcomes were OS and DFS; LFS was assessed as a secondary analysis, and late toxic effects as an exploratory analysis determined before start of the study. Results: The mean (SD) age of participants was 66 (12) years and 279 (88%) were men. Overall, 268 patients (84%) had N0 disease, and 150 (47%) received concurrent systemic therapy. The mean (SD) tumor volume was 4.04 (3.92) cm3. With a mean (SD) follow-up of 3.85 (3.04) years, there were 91 (29%) local, 35 (11%) regional, and 38 (12%) distant failures. Increasing tumor volume (per 1-cm3 increase) was associated with significantly worse adjusted OS (hazard ratio [HR], 1.07; 95% CI, 1.03-1.11) and DFS (HR, 1.04; 95% CI, 1.01-1.07). A total of 62 patients (19%) underwent laryngectomies with 54 (87%) of these within 800 days after treatment. Concurrent systemic therapy was associated with improved LFS (subdistribution HR, 0.63; 95% CI, 0.53-0.76). Conclusions and Relevance: Increasing tumor volumes in cT3 glottic cancers was associated with worse OS and DFS, and systemic therapy was associated with improved LFS. In absence of randomized clinical trial evidence, patients with poor pretreatment laryngeal function or those ineligible for systemic therapy may be considered for primary surgical resection with postoperative radiotherapy.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Laríngeas , Neoplasias da Língua , Masculino , Humanos , Idoso , Feminino , Neoplasias Laríngeas/patologia , Carcinoma de Células Escamosas/patologia , Estudos Retrospectivos , Carga Tumoral , Canadá , Neoplasias da Língua/terapia
15.
Indian J Ophthalmol ; 69(10): 2574-2584, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34571597

RESUMO

Magnetic resonance imaging (MRI) is an eloquent, noninvasive, cross-sectional imaging modality that offers superior tissue characterization of orbital pathologies. The ophthalmologist needs to be aware of the advantages of MRI and its step-wise interpretation in liaison with a radiologist to optimize patient outcomes. In this review, we discuss the basic principles of MRI, some of the commonly used sequences and protocols, the anatomy of the orbit on MRI, and an approach to radiological interpretation.


Assuntos
Imageamento por Ressonância Magnética , Órbita , Humanos , Órbita/diagnóstico por imagem , Radiografia , Tomografia Computadorizada por Raios X
16.
Indian J Ophthalmol ; 69(10): 2585-2616, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34571598

RESUMO

In this article we focus on a systematic approach to assess common orbital lesions on magnetic resonance imaging (MRI). The identification of the probable compartment or structure of origin helps narrow the differential diagnosis of a lesion. Analyzing the morphology, appearance, and signal intensity on various sequences, the pattern, and degree of contrast enhancement are key to characterize lesions on MRI. Imaging features suggesting cellularity and vascularity can also be determined to help plan for biopsy or surgery of these lesions. MRI can also distinguish active from chronic disease in certain pathologies and aids in selecting appropriate medical management. MRI may thus serve as a diagnostic tool and help in guiding therapeutic strategies and posttreatment follow-up.


Assuntos
Órbita , Neoplasias Orbitárias , Meios de Contraste , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Órbita/diagnóstico por imagem , Neoplasias Orbitárias/diagnóstico
17.
Children (Basel) ; 6(3)2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30862078

RESUMO

The etiology of epilepsy is variable and sometimes multifactorial. Clinical course and response to treatment largely depend on the precise etiology of the seizures. Along with the electroencephalogram (EEG), neuroimaging techniques, in particular, magnetic resonance imaging (MRI), are the most important tools for determining the possible etiology of epilepsy. Over the last few years, there have been many developments in data acquisition and analysis for both morphological and functional neuroimaging of people suffering from this condition. These innovations have increased the detection of underlying structural pathologies, which have till recently been classified as "cryptogenic" epilepsy. Cryptogenic epilepsy is often refractory to anti-epileptic drug treatment. In drug-resistant patients with structural or consistent functional lesions related to the epilepsy syndrome, surgery is the only treatment that can offer a seizure-free outcome. The pre-operative detection of the underlying structural condition increases the odds of successful surgical treatment of pharmacoresistant epilepsy. This article provides a comprehensive overview of neuroimaging techniques in epilepsy, highlighting recent advances and innovations and summarizes frequent etiologies of epilepsy in order to improve the diagnosis and management of patients suffering from seizures, especially young patients and children.

18.
Clin Neuroradiol ; 29(2): 191-213, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30887091

RESUMO

Incidentalomas are common in magnetic resonance imaging (MRI) of the spine. These incidental findings (IFs) can be seen involving the spinal cord, nerve root, vertebral body, posterior arch and the extraspinal region. This review article describes the imaging findings, stratifies the IFs similar to the computed tomography (CT) colonography reporting and data system and briefly mentions the current recommendations for further evaluation and management of IFs. Radiologists are the first to detect these lesions, suggest further evaluation and management of IFs. It is therefore mandatory for them to be aware of recommendations in clinical practice in order to avoid increased patient anxiety, excessive healthcare expenditure and inadvertent therapeutic procedures.


Assuntos
Doenças da Medula Espinal/diagnóstico , Doenças da Coluna Vertebral/diagnóstico , Coluna Vertebral/anormalidades , Artefatos , Colonografia Tomográfica Computadorizada/métodos , Cistos/diagnóstico , Humanos , Achados Incidentais , Imageamento por Ressonância Magnética , Raízes Nervosas Espinhais/diagnóstico por imagem , Tomografia Computadorizada por Raios X
19.
J Oral Maxillofac Pathol ; 23(1): 97-103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31110424

RESUMO

INTRODUCTION: The tumor-suppressor p53 protein is inactivated by the human papillomavirus (HPV) E6 oncoprotein, causing polymorphism of the p53 at codon 72 of exon either proline (Pro) or arginine (Arg). Specific allele predisposition has been reported in the literature. The association between the p53 allele and HPV types has been reported. We analyzed the association between p53 polymorphism at codon 72 and HPV 16 and 18 genotypes in control, oral submucous fibrosis (OSF) and oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Of the total 90 cases, biopsy tissues of all groups (30 cases of OSF, OSCC and control each) were collected to extract DNA. Polymerase chain reaction was used to detect HPV 16 and 18 and alleles of codon 72 in p53 were evaluated in all the samples. RESULTS: In control, OSF and OSCC samples showed the presence HPV 63.3%, 33.3% and 60%, respectively. In OSF, HPV 16 and 18 was detected in four and four cases, respectively, whereas in OSCC, HPV 16 and 18 was detected in ten and nine cases, respectively. In all three groups, predominantly, Arg/Arg protein was present followed by Pro/Pro and Arg/Pro. Among the control, Arg/Arg type protein was frequently seen followed by Arg/Pro, Pro/Pro in the presence of HPV. OSF and OSCC were associated homologous genes in the presence of HPV. CONCLUSION: The definite association between p53 codon 72, polymorphism and HPV 16 and 18 was seen in OSCC with low frequency in OSF. Frequency of homozygous genotype is at high risk in the presence of HPV 16 and 18 in developing OSCC.

20.
Indian J Radiol Imaging ; 29(4): 343-349, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31949334

RESUMO

OBJECTIVES: To highlight the typical magnetic resonance imaging (MRI) findings in hyperglycemia-induced seizures and compare the results with similar previous studies with a brief mention of pathophysiological mechanisms. MATERIALS AND METHODS: This retrospective study included medical and imaging records of six consecutive patients with hyperglycemia-induced seizures. The data analysis included a clinical presentation and biochemical parameters at admission. The MRI sequences were evaluated for region involved, presence of subcortical T2 hypo-intensity, cortical hyper-intensity, and restricted diffusion. Similar previous studies from the National Library of Medicine (NLM) were analyzed and compared with our study. RESULTS: Twenty-four patients were included from four studies in previous literature for comparison. In our study, on imaging, posterior cerebral region was predominantly involved, with parietal involvement in 83.3%, followed by occipital, frontal, and temporal involvement in 33.3% patients compared with occipital in 58.3%, parietal in 45.8%, and frontal and temporal in 16.6% of patients in previous literature. The subcortical T2 hypo-intensity was present in 83.3% of the patients, cortical hyper-intensity in all patients, and restricted diffusion in 66.6% of the patients in our study compared with subcortical T2 hypo-intensity in 95.8% of the patients, cortical hyper-intensity in 62.5%, and restricted diffusion in 58.3% of the patients in previous literature. CONCLUSION: Although many etiologies present with subcortical T2 hypointensity, cortical hyperintensity, restricted diffusion, and postcontrast enhancement on MRI, the clinical setting of seizures in a patient with uncontrolled hyperglycemia, hyperosmolar state, and absence of ketones should suggest hyperglycemia-induced seizures to avoid misdiagnosis, unnecessary invasive investigations, and initiate timely management. ADVANCES IN KNOWLEDGE: Our study highlights the presence of posterior predominant subcortical T2, fluid-attenuated inversion recovery (FLAIR), and susceptibility-weighted angiography (SWAN) hypointensity; cortical hyperintensity; and restricted diffusion in hyperglycemia-induced seizures. The presence of T2 and SWAN hypointensity could support the hypothesis of possible deposition of free radicals and iron in the subcortical white matter.

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