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OBJECTIVES: Prophylactic cerclage cables are often placed intraoperatively about a fracture to prevent propagation. However, biomechanical data supporting optimal cable placement location are lacking. The objective of this study was to evaluate the impact of prophylactic cerclage placement location on the propagation of femoral shaft fractures. METHODS: The diaphysis of 14 fresh-frozen cadaveric femora were included. Volumetric bone mineral density in the femoral shaft was obtained from quantitative computed tomography scans. For each specimen, a 5-mm longitudinal fracture was created proximally to simulate a pre-existing fracture. After reaming of the femoral canal, a 3 degrees tapered wedge was advanced with an MTS machine at 0.2 mm/s until failure. The tests were conducted with a CoCr cable placed at varying distances (5 mm, 10 mm, 15 mm, 20 mm, and cableless) from the distal tip of the initial fracture. A compression loadcell was used to measure the cable tension during the tests. The axial force, displacement, and cable tension were monitored for comparison between groups. RESULTS: In the cableless group, the mean force needed to propagate the fracture was 1017.8 ± 450.3 N. With the addition of a cable at 5 mm below the fracture, the failure force nearly doubled to 1970.4 ± 801.1 N (P < 0.001). This also led to significant increases in stiffness (P = 0.006) and total work (P = 0.001) when compared with the control group. By contrast, in the 15 and 20 mm groups, there were no significant changes in the failure force, stiffness, and total work as compared with the control group (P > 0.05). CONCLUSIONS: Propagation of femoral shaft fracture was effectively resisted when a prophylactic cable was placed within 5 mm from the initial fracture, whereas cables placed more than 10 mm below the initial fracture were not effective in preventing fracture propagation.
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Cadáver , Fraturas do Fêmur , Humanos , Fraturas do Fêmur/cirurgia , Fraturas do Fêmur/prevenção & controle , Fraturas do Fêmur/fisiopatologia , Feminino , Idoso , Masculino , Fenômenos Biomecânicos , Fios Ortopédicos , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Idoso de 80 Anos ou mais , Pessoa de Meia-IdadeRESUMO
BACKGROUND AND PURPOSE: Sotos syndrome is a rare autosomal dominant condition caused by pathogenic mutations in the NSD1 gene that presents with craniofacial dysmorphism, overgrowth, seizures, and neurodevelopmental delay. Macrocephaly, ventriculomegaly, and corpus callosal dysmorphism are typical neuroimaging features that have been described in the medical literature. The purpose of this study was to expand on the neuroimaging phenotype by detailed analysis of a large cohort of patients with genetically proved Sotos syndrome. MATERIALS AND METHODS: This multicenter, multinational, retrospective observational cohort study systematically analyzed the clinical characteristics and neuroimaging features of 77 individuals with genetically diagnosed Sotos syndrome, via central consensus review with 3 pediatric neuroradiologists. RESULTS: In addition to previously described features, malformations of cortical development were identified in most patients (95.0%), typically dysgyria (92.2%) and polymicrogyria (22.1%), varying in location and distribution. Incomplete rotation of the hippocampus was observed in 50.6% of patients and was associated with other imaging findings, in particular with dysgyria (100% versus 84.2%, P = .012). CONCLUSIONS: Our findings show a link between the genetic-biochemical basis and the neuroimaging features and aid in better understanding the underlying clinical manifestations and possible treatment options. These findings have yet to be described to this extent and correspond with recent studies that show that NSD1 participates in brain development and has interactions with other known relevant genetic pathways.
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This review delves into the most recent advancements in applying artificial intelligence (AI) within neuro-oncology, specifically emphasizing work on gliomas, a class of brain tumors that represent a significant global health issue. AI has brought transformative innovations to brain tumor management, utilizing imaging, histopathological, and genomic tools for efficient detection, categorization, outcome prediction, and treatment planning. Assessing its influence across all facets of malignant brain tumor management- diagnosis, prognosis, and therapy- AI models outperform human evaluations in terms of accuracy and specificity. Their ability to discern molecular aspects from imaging may reduce reliance on invasive diagnostics and may accelerate the time to molecular diagnoses. The review covers AI techniques, from classical machine learning to deep learning, highlighting current applications and challenges. Promising directions for future research include multimodal data integration, generative AI, large medical language models, precise tumor delineation and characterization, and addressing racial and gender disparities. Adaptive personalized treatment strategies are also emphasized for optimizing clinical outcomes. Ethical, legal, and social implications are discussed, advocating for transparency and fairness in AI integration for neuro-oncology and providing a holistic understanding of its transformative impact on patient care.
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BACKGROUND: Outcomes of infants following surgical necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP) categorized by the age of onset, interventions, and sex are not well defined. METHODS: Retrospective comparison of infants categorized by age of onset (NEC at <10, 10-20, and >20 days) and SIP at <7 versus ≥7 days), sex, and intervention [Penrose Drain (PD) vs. laparotomy]. RESULTS: A total of 114 infants had NEC and 37 had SIP. On multinomial logistic regression, infants with NEC/SIP onset >20 days had significantly lower odds of small bowel involvement (aOR = 0.07, 95% CI: 0.01-0.33, p = 0.001), higher necrosis (aOR = 3.59, 95% CI: 1.34-9.65, p = 0.012) and higher CRP (p = 0.004) than onset <10 days. Initial laparotomy was associated with more bowel loss (24.1 cm [12.3; 40.6] vs.12.1 [8.00; 23.2]; p = 0.001), small and large intestine involvement (47.1% vs 17.2%; p = 0.01), and ileocecal valve resection (42% vs. 19.4%; p = 0.036) than initial PD therapy. Females underwent fewer small bowel resections (52.3% vs 73.6%; p = 0.025) but had higher surgical morbidity (53.7% vs. 24.7%.; p = 0.001) than males. CONCLUSION: Clinical, radiological, and histopathological presentation and outcomes in preterm infants with surgical NEC/SIP are associated with age of disease onset, sex, and initial intervention. IMPACT: Neonates with surgical NEC onset >20 days had more severe necrosis, inflammation, kidney injury, and bowel loss than those with <10 days. Initial laparotomy was associated with later age onset, more bowel loss, and ileocecal valve resection compared to initial PD treatment, but not with differences in mortality or length of stay. Female sex was associated with lower maturity, more placental malperfusion, less often small bowel involvement, lower pre-NEC hematocrit as well as higher surgical morbidity than males. Whether the management of surgical NEC and SIP should differ by the age of onset requires further investigation.
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Enterocolite Necrosante , Perfuração Intestinal , Lactente , Masculino , Recém-Nascido , Humanos , Feminino , Gravidez , Recém-Nascido Prematuro , Perfuração Intestinal/cirurgia , Estudos Retrospectivos , Placenta/patologia , Enterocolite Necrosante/terapia , Necrose/complicaçõesRESUMO
Vertebral artery dissection (VAD) is a common cause of a rare condition, pediatric posterior circulation arterial ischemic stroke (PCAIS). VAD is clinically important due to the risk of multifocal and continuing infarcts from artery-to-artery thromboembolism, with the potential for occlusion of arteries that perfuse the brainstem. Early diagnosis is important, as recurrent stroke is a common effect of VAD in children. Although the relative efficacies of different treatment regimens for VAD in children remain unsettled, early initiation of treatment can mitigate the risk of delayed stroke. Clinical diagnosis of PCAIS may be delayed due to multiple factors, including nonspecific symptoms and the inability of younger patients to express symptoms. In fact, subacute or chronic infarcts are often present at initial imaging. Although the most common cause of isolated PCAIS is VAD, imaging of the cervical arteries has been historically underused in this setting. Cervical vascular imaging (MR angiography, CT angiography, and digital subtraction angiography) for VAD must be optimized to detect the sometimes subtle findings, which may be identified at initial or follow-up imaging. Osseous variants of the craniocervical junction and upper cervical spine and other extrinsic lesions that may directly injure the vertebral arteries or lead to altered biomechanics have been implicated in some cases. The authors review characteristic imaging features and optimized imaging of VAD and associated PCAIS and related clinical considerations. Identification of VAD has important implications for evaluation, treatment, and imaging follow-up, as this condition may result in progressive arteriopathy and recurrent stroke. © RSNA, 2023 Supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.
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Acidente Vascular Cerebral , Dissecação da Artéria Vertebral , Humanos , Criança , Dissecação da Artéria Vertebral/complicações , Dissecação da Artéria Vertebral/diagnóstico por imagem , Angiografia por Ressonância Magnética , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/patologia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Infarto/complicações , Infarto/patologiaRESUMO
Contextual design and selection of MRI protocols is critical for making an accurate diagnosis given the wide variety of clinical indications for spine imaging in children. Here, we describe our pediatric spine imaging protocols in detail, tailored to specific clinical questions.
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OBJECTIVE: To compare the clinical outcomes in preterm infants following surgical necrotizing enterocolitis (sNEC) and spontaneous intestinal perforation (SIP). METHODS: Retro-spective comparison of clinical information in preterm infants with sNEC and SIP admitted between January, 2013 and December 31, 2018. The clinical outcomes were compared in two groups, including postoperative and brain injury detected on brain magnetic resonance imaging (MRI) after clinical and histopathological confirmation of the SIP and the NEC diagnosis. RESULTS: 114 infants had sNEC, and 37 had SIP. Infants with SIP had lower median gestational age [25.1 weeks (23.5, 27.1) vs 26.6 (24.4, 31.0), P=0.03], an earlier mean (SD) age of disease onset [10.1 (11.3) days vs 19.6 (17.9); P<0.001] and lower maternal chorioamnionitis on placental pathology [4 (23.5%) vs 22 (68.8%); P=0.007), received more often Penrose drain therapy (54% vs 33%; P=0.03), had less median (IQR) bowel length loss [3.3 cm (1.72, 4.38) vs 21.4 (9.55, 35.3); P=<0.001] and had more often intact ileocecal valve (91.4% vs 65.7%; P=0.006] compared to those with sNEC. In addition, those with sNEC had lower median (IQR) weight z scores at the time of discharge [-1.88 (-2.80, -1.09) vs -1.14 (-2.22, -0.44); P=0.036] than SIP. There were no significant differences in postoperative ileus, duration of parenteral nutrition, surgical morbidity, length of stay, mortality, white matter, and grey matter injury on brain MRI at term equivalent age in preterm infants with SIP and sNEC. CONCLUSION: In our cohort, preterm infants with SIP and sNEC did not show significant differences in postoperative morbidity and brain MRI abnormalities at term equivalent age. sNEC had lower discharge weight z scores. Larger prospective studies are needed for confirmation of these findings.
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Lesões Encefálicas , Enterocolite Necrosante , Doenças do Recém-Nascido , Perfuração Intestinal , Lactente , Recém-Nascido , Humanos , Feminino , Gravidez , Recém-Nascido Prematuro , Perfuração Intestinal/cirurgia , Perfuração Intestinal/diagnóstico , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/cirurgia , Enterocolite Necrosante/diagnóstico , Placenta/patologia , Estudos RetrospectivosRESUMO
BACKGROUND: Brain imaging has been utilized as a diagnostic tool in the workup of persistent pediatric dysphagia, yet the indications for imaging and the prevalence of Chiari malformation (CM) have not been established. OBJECTIVE: to evaluate the prevalence of CM anomalies in children who underwent brain magnetic resonance imaging (MRI) for pharyngeal dysphagia and to review the clinical findings in the CM group compared to the non-CM group. METHODS: A retrospective cohort study of children who underwent MRI as part of the workup for the diagnosis of dysphagia in a tertiary care children's hospital between 2010 and 2021. RESULTS: 150 patients were included. The mean age at diagnosis of dysphagia was 1 ± 3.4 years, and the mean age at MRI was 3.5 ± 4.2 years. Common comorbidities in our cohort included prematurity (n = 70, 46.7 %), gastroesophageal reflux (n = 65, 43.3 %), neuromuscular/seizure disorder (n = 53,35.3 %), and underlying syndrome (n = 16, 10.7 %). Abnormal brain findings were seen in 32 (21.3 %) patients, of whom 5 (3.3 %) were diagnosed with CM-I and 4 (2.7 %) patients with tonsillar ectopia. Clinical characteristics and dysphagia severity were similar between patients with CM-I/tonsillar ectopia and patients without tonsillar herniation. CONCLUSIONS: Brain MRI should be pursued as part of the work-up for persistent dysphagia in pediatric patients given the relatively higher prevalence of CM-I. Multi-institutional studies are required to establish the criteria and timing of brain imaging in patients with dysphagia.
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Malformação de Arnold-Chiari , Transtornos de Deglutição , Criança , Pré-Escolar , Humanos , Malformação de Arnold-Chiari/complicações , Malformação de Arnold-Chiari/diagnóstico por imagem , Malformação de Arnold-Chiari/epidemiologia , Encéfalo/patologia , Transtornos de Deglutição/epidemiologia , Transtornos de Deglutição/etiologia , Imageamento por Ressonância Magnética , Prevalência , Estudos RetrospectivosRESUMO
BACKGROUND: Due to increasing volume of total hip arthroplasties, periprosthetic femoral fractures have become a common complication with increased revision burden and perioperative morbidity. The objective of this study was to evaluate the fixation stability of Vancouver B2 fractures treated with 2 techniques. METHODS: A common B2 fracture was created by reviewing 30 type B2 cases. The fracture was then reproduced in 7 pairs of cadaveric femora. The specimens were divided into 2 groups. In Group I ("reduce-first"), the fragments were reduced first, followed by implantation of a tapered fluted stem. In Group II ("ream-first"), the stem was implanted in the distal femur first, followed by fragment reduction and fixation. Each specimen was loaded in a multiaxial testing frame with 70% of peak load during walking. A motion capture system was used to track the motion of the stem and fragments. RESULTS: The average stem diameter in Group II was 16.1 ± 0.4 mm, versus 15.4 ± 0.5 mm in Group I. The fixation stability was not significantly different in the 2 groups. After the testing, the average stem subsidence was 0.36 ± 0.31 mm and 0.19 ± 0.14 mm (P = .17) and the average rotation was 1.67 ± 1.30° and 0.91 ± 1.11° (P = .16) in Groups I and II, respectively. Compared to the stem, there was less motion of the fragments and there was no difference between the 2 groups (P > .05). CONCLUSIONS: When tapered fluted stems were used in combination with cerclage cables for treatment of Vancouver type B2 periprosthetic femoral fractures, both the "reduce-first" and "ream-first" techniques showed adequate stem and fracture stability.
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Artroplastia de Quadril , Fraturas do Fêmur , Prótese de Quadril , Fraturas Periprotéticas , Humanos , Prótese de Quadril/efeitos adversos , Reoperação/efeitos adversos , Resultado do Tratamento , Artroplastia de Quadril/efeitos adversos , Fraturas Periprotéticas/cirurgia , Fraturas Periprotéticas/complicações , Fêmur/cirurgia , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Estudos RetrospectivosRESUMO
Radiation therapy (RT) is a critical part of definitive therapy for pediatric high-grade glioma (pHGG). RT is designed to treat residual tumor defined on conventional MRI (cMRI), though pHGG lesions may be ill-characterized on standard imaging. Spectroscopic MRI (sMRI) measures endogenous metabolite concentrations in the brain, and Choline (Cho)/N-acetylaspartate (NAA) ratio is a highly sensitive biomarker for metabolically active tumor. We provide a preliminary report of our study introducing a novel treatment approach of whole brain sMRI-guided proton therapy for pHGG. An observational cohort (c1 = 10 patients) receives standard of care RT; a therapeutic cohort (c2 = 15 patients) receives sMRI-guided proton RT. All patients undergo cMRI and sMRI, a high-resolution 3D whole-brain echo-planar spectroscopic imaging (EPSI) sequence (interpolated resolution of 12 µL) prior to RT and at several follow-up timepoints integrated into diagnostic scans. Treatment volumes are defined by cMRI for c1 and by cMRI and Cho/NAA ≥ 2x for c2. A longitudinal imaging database is used to quantify changes in lesion and metabolite volumes. Four subjects have been enrolled (c1 = 1/c2 = 3) with sMRI imaging follow-up of 4-18 months. Preliminary data suggest sMRI improves identification of pHGG infiltration based on abnormal metabolic activity, and using proton therapy to target sMRI-defined high-risk regions is safe and feasible.
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Neoplasias Encefálicas , Glioma , Terapia com Prótons , Humanos , Criança , Espectroscopia de Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Glioma/diagnóstico por imagem , Glioma/radioterapia , Imageamento por Ressonância Magnética/métodosRESUMO
Objective: Determine the risk factors of cerebellar injury in infants with surgical necrotizing enterocolitis (NEC). Methods: Retrospective study compared clinical/pathological information between surgical NEC infants with and those without cerebellar injury. Results: Infants with cerebellar injury (21/65, 32.3%) had significantly more hemorrhagic and the reparative lesions on the intestinal histopathology, had patent ductus arteriosus (PDA) more often, received red cell transfusion frequently, had blood culture positive sepsis and grew gram positive organisms more often and had cholestasis frequently following NEC than those without cerebellar injury. On multilogistic regression, the positive blood culture sepsis (OR 3.9, CI 1.1-13.7, p = 0.03), PDA (OR 4.5, CI 1.0-19.9, p = 0.04) and severe hemorrhage (grade 3-4)(OR 16.9, CI 2.1-135.5, p = 0.007) were independently associated with higher risk of cerebellar injury. Conclusion: The cerebellar injury was most likely associated with positive blood culture sepsis following NEC, PDA, and severe hemorrhage lesions (grade 3-4) in infants with surgical NEC.
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BACKGROUND: To evaluate post-operative outcomes and white matter injury (WMI) using brain MRI at term equivalent in neonates with and without severe acute kidney injury (AKI) following surgical necrotizing enterocolitis (NEC). METHODS: A retrospective cohort study comparing neonates with severe (Stage 2/3) vs. other (no AKI/Stage 1) AKI using KDIGO classification with multivariable models assessing this association in the context of multiple systemic comorbidities. RESULTS: Of 103 neonates with surgical NEC, 60 (58%) had severe AKI. Those with severe AKI had lower birth weight (BW; 715 vs. 950 g; p = .023), more frequently treated with indomethacin (18.3 vs. 2.4%); p = .014), higher CRP levels at 24 h after NEC onset (14.4 [6.4-19.8] vs. 4.8 [1.6-13.4]; p = .005), higher presence of cholestasis (73.3 vs. 51.2%); p = .023), later age of NEC onset (14 vs. 7 d); p = .004), longer length of bowel resected (14.9 vs. 4.3 cm); p = .011), longer post-operative ileus days (14 vs. 9 d); p < .001), longer post-operative days at starting enteral feedings (15 vs. 10 d; p < .001), longer days of attainment of full enteral feedings (75 vs. 44.5 d; p = .008) and longer length of stay (140.5 vs. 94 d; p = .028) compared to those without severe AKI. Compared to infants without AKI by serum creatinine, those with AKI had significantly more cases of white matter abnormality (WMA; 90 vs. 36.6%; p < .001) and retinopathy of prematurity (63.9 vs. 35.3%; p = .017). In addition, the presence of AKI Stage 2 and 3 by serum creatinine was independently associated with higher odds of sustaining severe WMI level on an ordinal scale (OR = 6.2; 95% CI = (1.1-35.5); p = .041). CONCLUSIONS: Neonates with severe AKI following surgical NEC were more likely to experience longer post-operative morbidity and higher WMI by MRI at term.
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Injúria Renal Aguda , Lesões Encefálicas , Enterocolite Necrosante , Doenças do Recém-Nascido , Lactente , Recém-Nascido , Humanos , Enterocolite Necrosante/complicações , Enterocolite Necrosante/cirurgia , Recém-Nascido Prematuro , Estudos Retrospectivos , Creatinina , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/complicaçõesRESUMO
"Inherited metabolic disorders represent a large group of disorders of which approximately 25% present in neonatal period with acute metabolic decompensation, rapid clinical deterioration, and often nonspecific imaging findings. Neonatal onset signifies the profound severity of the metabolic abnormality compared with cases with later presentation and necessitates rapid diagnosis and urgent therapeutic measures in an attempt to decrease the extent of brain injury and prevent grave neurologic sequela or death. Here, the authors discuss classification and clinical and imaging findings in a spectrum of metabolic and endocrine disorders with neonatal presentation."
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Doenças do Sistema Endócrino , Doenças do Sistema Endócrino/diagnóstico por imagem , Humanos , Recém-NascidoRESUMO
BACKGROUND: The objective of this study was to determine the risk factors and outcomes of white matter brain injury (WMBI) on magnetic resonance imaging (MRI) at term-equivalent age in infants with surgical necrotizing enterocolitis (NEC). METHODS: This retrospective study compared clinical/pathological information between infants with and those without WMBI. RESULTS: Out of 69 infants with surgical NEC, 17 (24.6%) had mild WMBI, 13 (18.8%) had moderate WMBI, and six (8.7%) had severe WMBI on the brain MRI. Several clinical factors (gestational age, more red blood cell (RBC) transfusions before NEC onset, pneumoperitoneum, earlier NEC onset age, postoperative ileus, acute kidney injury (AKI) by serum creatinine, postnatal steroids, hospital stay) and histopathological findings (necrosis, hemorrhage) had univariate associations with WMBI. Associations with RBC transfusion (odds ratio (OR) 23.6 [95% confidence interval (CI): 4.73-117.97]; p = 0.0001), age at NEC onset (OR 0.30 [95%CI: 0.11-0.84]; p = 0.021), necrosis (OR 0.10 [95%CI: 0.01-0.90]; p = 0.040), and bowel hemorrhage (OR 7.79 [95%CI: 2.19-27.72]; p = 0.002) persisted in multivariable association with grade 3-4 WMBI. The infants with WMBI had lower mean motor, cognitive, language scores, and higher ophthalmic morbidity at 2 years of age. CONCLUSIONS: The WMBI was most likely associated with earlier NEC onset, higher RBC transfusions, and less necrosis and greater hemorrhage lesions on intestinal pathology in preterm infants with surgical NEC. IMPACT: In preterm infants with surgical NEC, brain MRI showed injury in the white matter in 52%, gray matter in 10%, and cerebellar region in 30%. Preterm infants with severe WMBI (grade 3-4) had less necrosis and greater hemorrhagic lesions on histopathology of the bowel. Preterm infants with WMBI were more likely to have a more severe postoperative course, AKI, and longer length of hospitalization. Neuroprotective strategies to prevent brain injury in preterm infants with surgical NEC are needed with the goal of improving the neurodevelopmental outcomes.
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Injúria Renal Aguda , Lesões Encefálicas , Enterocolite Necrosante , Doenças Fetais , Doenças do Recém-Nascido , Injúria Renal Aguda/complicações , Injúria Renal Aguda/terapia , Lesões Encefálicas/complicações , Enterocolite Necrosante/prevenção & controle , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Necrose/complicações , Estudos Retrospectivos , Fatores de RiscoRESUMO
INTRODUCTION: Deep brain stimulation of the zona incerta is effective at treating tremor and other forms of parkinsonism. However, the structure is not well visualized with standard MRI protocols making direct surgical targeting unfeasible and contributing to inconsistent clinical outcomes. In this study, we applied coronal gradient echo MRI to directly visualize the rostral zona incerta in Parkinson's disease patients to improve targeting for deep brain stimulation. METHODS: We conducted a prospective study to optimize and evaluate an MRI sequence to visualize the rostral zona incerta in patients with Parkinson's disease (n = 31) and other movement disorders (n = 13). We performed a contrast-to-noise ratio analysis of specific regions of interest to quantitatively assess visual discrimination of relevant deep brain structures in the optimized MRI sequence. Regions of interest were independently assessed by 2 neuroradiologists, and interrater reliability was assessed. RESULTS: Rostral zona incerta and subthalamic nucleus were well delineated in our 5.5-min MRI sequence, indicated by excellent interrater agreement between neuroradiologists for region-of-interest measurements (>0.90 intraclass coefficient). Mean contrast-to-noise ratio was high for both rostral zona incerta (6.39 ± 3.37) and subthalamic nucleus (17.27 ± 5.61) relative to adjacent white matter. There was no significant difference between mean signal intensities or contrast-to-noise ratio for Parkinson's and non-Parkinson's patients for either structure. DISCUSSION/CONCLUSION: Our optimized coronal gradient echo MRI sequence delineates subcortical structures relevant to traditional and novel deep brain stimulation targets, including the zona incerta, with high contrast-to-noise. Future studies will prospectively apply this sequence to surgical planning and postimplantation outcomes.
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Estimulação Encefálica Profunda , Doença de Parkinson , Zona Incerta , Humanos , Imageamento por Ressonância Magnética , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/terapia , Estudos Prospectivos , Reprodutibilidade dos Testes , Zona Incerta/diagnóstico por imagemRESUMO
Background: Norrie disease is a genetic disorder of the retina characterized by impaired retinal vascular development leading to retinal detachment and blindness. Non-retinal manifestations of the disorder include intellectual disability and seizure disorders. However, to date, no association with neurological mass lesions has been described.Materials and methods: Case reporResults: Here, we report a case of a patient with Norrie disease who presented with an enhancing mass of the choroid plexus that spontaneously diminished in size. Conclusion: This report suggests watchful waiting as a reasonable clinical approach to choroid plexus lesions in patients with Norrie disease.
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Cegueira/congênito , Encefalopatias/diagnóstico por imagem , Plexo Corióideo/diagnóstico por imagem , Proteínas do Olho/genética , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Mutação/genética , Proteínas do Tecido Nervoso/genética , Doenças do Sistema Nervoso/diagnóstico , Degeneração Retiniana/diagnóstico , Espasmos Infantis/diagnóstico , Cegueira/diagnóstico , Cegueira/genética , Encefalopatias/fisiopatologia , Plexo Corióideo/fisiopatologia , Doenças Genéticas Ligadas ao Cromossomo X/genética , Idade Gestacional , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Doenças do Sistema Nervoso/genética , Degeneração Retiniana/genética , Espasmos Infantis/genéticaRESUMO
Drug delivery to the posterior segment of the eye remains challenging even though the eye is readily accessible. Its unique and complex anatomy and physiology contribute to the limited options for drug delivery via non-invasive topical treatment, which is the prevalent ophthalmic treatment. To treat the most common retinal diseases, intravitreal (IVT) injection has been a common and effective therapy. With the advancement of nanotechnologies, novel formulations and drug delivery systems are being developed to treat posterior segment diseases. Here, we discuss the recent advancement in ocular delivery systems, including-sustained release formulations, IVT implants, and preclinical topical formulations, and the challenges faced in their clinical translation.
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Soluções Oftálmicas/administração & dosagem , Segmento Posterior do Olho/efeitos dos fármacos , Doenças Retinianas/tratamento farmacológico , Administração Tópica , Animais , Preparações de Ação Retardada/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , HumanosRESUMO
AIM: The purpose of this study was to evaluate the effect of post space preparation on the sealing ability of teeth obturated with mineral trioxide aggregate (MTA) and Gutta-percha. MATERIALS AND METHODS: Fifty intact human mandibular premolars, after decoronation and biomechanical preparation, were randomly divided into three experimental groups. In Group A (n = 10), the canals were obturated with Gutta-percha using cold lateral compaction technique, followed by immediate post space preparation. In Group B (n = 10), the canals were obturated with 8 mm of MTA and in Group C (n = 10), sectional obturation with 4 mm of MTA was done, followed by delayed post space preparation. All specimens were subjected to bacterial leakage analysis, and the occurrence of turbidity was checked. RESULTS: All specimens in the lateral compaction group leaked. The mean number of days at which leakage was observed in Groups A, B and C were 18.5 days, 93.6 days and 95.5 days. CONCLUSIONS: MTA can be considered as an alternative to Gutta-percha as an apical third restorative material for teeth indicated for post and core, as it demonstrates better-sealing ability compared with Gutta-percha. Further, the removal of set MTA for post space preparation does not disrupt the integrity of the remaining apical MTA.