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1.
Stroke ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881452

RESUMO

BACKGROUND: Surgical risk assessment is intriguing for clinical decision-making of brainstem cavernous malformation (BSCM) treatment. While the BSCM grading scale, encompassing size, developmental venous anomaly, crossing axial midpoint, age, and timing of intervention, is increasingly utilized, the clinical relevance of neurological fluctuation and recurrent hemorrhage has not been incorporated. This study aimed to propose a supplementary grading scale with enhanced predictive efficacy. METHODS: Using a retrospective nationwide registry of consecutive patients with BSCMs undergoing surgery in China from March 2011 to May 2023, a new supplementary BSCM grading scale was developed from a derivative cohort of 260 patients and validated in an independent concurrent cohort of 67 patients. The primary outcome was unfavorable neurological function (modified Rankin Scale score >2) at the latest follow-up. The performance of the supplementary grading system was evaluated for discrimination, calibration, and clinical utility and further compared with its original counterpart. RESULTS: Over a follow-up of at least 6 months after surgery, the unfavorable outcomes were 31% in the overall cohort (101/327 patients). A preoperative motor deficit (odds ratio, 3.13; P=0.001), recurrent hemorrhage (odds ratio, 3.05; P<0.001), timing of intervention (odds ratio, 7.08; P<0.001), and crossing the axial midpoint (odds ratio, 2.57; P=0.006) were associated with the unfavorable outcomes and composed the initial Huashan grading variables. A supplementary BSCM grading system was subsequently developed by incorporating the Huashan grading variables into the original BSCM grading scale. The predictive capability of the supplementary scale was consistently superior to the original counterpart in either the derivative cohort (area under the receiver operating characteristic curve, 0.74 [95% CI, 0.68-0.80] for the supplementary versus 0.68 [95% CI, 0.61-0.74] for the original) or the validation cohort (0.75 [95% CI, 0.62-0.87] versus 0.64 [95% CI, 0.48-0.81]). CONCLUSIONS: This study highlights the neurological relevance of BSCM hemorrhage in surgical risk assessment. Via compositing preoperative motor function and recurrent hemorrhages, a supplementary grading scale may improve a dynamic risk assessment for clinical decisions in the management of BSCMs.

2.
Metabolites ; 14(6)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38921437

RESUMO

Thyrotropin-releasing hormone (TRH; pGlu-His-Pro-NH2) is an intercellular signal produced mainly by neurons. Among the multiple pharmacological effects of TRH, that on food intake is not well understood. We review studies demonstrating that peripheral injection of TRH generally produces a transient anorexic effect, discuss the pathways that might initiate this effect, and explain its short half-life. In addition, central administration of TRH can produce anorexic or orexigenic effects, depending on the site of injection, that are likely due to interaction with TRH receptor 1. Anorexic effects are most notable when TRH is injected into the hypothalamus and the nucleus accumbens, while the orexigenic effect has only been detected by injection into the brain stem. Functional evidence points to TRH neurons that are prime candidate vectors for TRH action on food intake. These include the caudal raphe nuclei projecting to the dorsal motor nucleus of the vagus, and possibly TRH neurons from the tuberal lateral hypothalamus projecting to the tuberomammillary nuclei. For other TRH neurons, the anatomical or physiological context and impact of TRH in each synaptic domain are still poorly understood. The manipulation of TRH expression in well-defined neuron types will facilitate the discovery of its role in food intake control in each anatomical scene.

3.
Eur J Clin Invest ; : e14259, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38845111

RESUMO

BACKGROUND: The commonest echocardiographic measurement, left ventricular ejection fraction, can not necessarily predict mortality of recipients following heart transplantation potentially due to afterload dependency. Afterload-independent left ventricular stroke work index (LVSWI) is alternatively recommended by the current guideline; however, pulmonary artery catheters are rarely inserted in organ donors in most jurisdictions. We propose a novel non-invasive echocardiographic parameter, Pressure-Strain Product (PSP), as a potential surrogate of catheter-based LVSWI. This study aimed to investigate if PSP could correlate with catheter-based LVSWI in an ovine model of brain stem death (BSD) donors. The association between PSP and myocardial mitochondrial function in the post-transplant hearts was also evaluated. METHODS: Thirty-one female sheep (weight 47 ± 5 kg) were divided into two groups; BSD (n = 15), and sham neurologic injury (n = 16). Echocardiographic parameters including global circumferential strain (GCS) and global radial strain (GRS) and pulmonary artery catheter-based LVSWI were simultaneously measured at 8-timepoints during 24-h observation. PSP was calculated as a product of GCS or GRS, and mean arterial pressure for PSPcirc or PSPrad, respectively. Myocardial mitochondrial function was evaluated following 6-h observation after heart transplantation. RESULTS: In BSD donor hearts, PSPcirc (n = 96, rho = .547, p < .001) showed the best correlation with LVSWI among other echocardiographic parameters. PSPcirc returned AUC of .825 to distinguish higher values of cardiomyocyte mitochondrial function (cut-off point; mean value of complex 1,2 O2 Flux) in post-transplant hearts, which was greater than other echocardiographic parameters. CONCLUSIONS: PSPcirc could be used as a surrogate of catheter-based LVSWI reflecting mitochondrial function.

4.
J Neurophysiol ; 131(6): 1299-1310, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691532

RESUMO

Although recent studies in nonhuman primates have provided evidence that transcranial magnetic stimulation (TMS) activates cells within the reticular formation, it remains unclear whether descending brain stem projections contribute to the generation of TMS-induced motor evoked potentials (MEPs) in skeletal muscles. We compared MEPs in muscles with extensive direct corticomotoneuronal input (first dorsal interosseous) versus a prominent role in postural control (gastrocnemius) to determine whether the amplitudes of early and late MEPs were differentially modulated by cortical suppression. Suprathreshold TMS was applied with and without a preceding suprathreshold TMS pulse at two interstimulus intervals (50 and 80 ms). H reflexes in target muscles were also tested with and without TMS conditioning. Early and late gastrocnemius MEPs were differentially modulated by cortical inhibition, the amplitude of the early MEP being significantly reduced by cortical suppression and the late MEP facilitated. The amplitude of H reflexes in the gastrocnemius was reduced within the cortical silent period. Early MEPs in the first dorsal interosseous were also reduced during the silent period, but late MEPs were unaffected. Independent modulation of early and late MEPs in the gastrocnemius muscle supports the idea that the MEP is generated by multiple descending pathways. Suppression of the early MEP is consistent with transmission along the fast-conducting corticospinal tract, whereas facilitation of the late MEP suggests transmission along a corticofugal, potentially cortico-reticulospinal, pathway. Accordingly, differences in late MEP modulation between the first dorsal interosseous and gastrocnemius reflect an increased role of corticofugal pathways in the control of postural muscles.NEW & NOTEWORTHY Early and late portions of the response to transcranial magnetic stimulation (TMS) in a lower limb postural muscle are modulated independently by cortical suppression, late motor evoked potentials (MEPs) being facilitated during cortical inhibition. These results suggest a cortico-brain stem transmission pathway for late portions of the TMS-induced MEP.


Assuntos
Potencial Evocado Motor , Extremidade Inferior , Músculo Esquelético , Estimulação Magnética Transcraniana , Masculino , Humanos , Músculo Esquelético/fisiologia , Potencial Evocado Motor/fisiologia , Adulto , Feminino , Extremidade Inferior/fisiologia , Córtex Motor/fisiologia , Reflexo H/fisiologia , Adulto Jovem , Tratos Piramidais/fisiologia
5.
BMJ Case Rep ; 17(5)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806398

RESUMO

Hashimoto encephalopathy presents with a myriad of neuropsychiatric features in the background of elevated antithyroid antibodies and it may or may not be associated with Hashimoto thyroiditis. It is a diagnosis of exclusion. Here, we present the case of a hypothyroid woman in her 30s, with a 5-year history of chronic progressive gait ataxia along with hand and head tremor, inattention and electroencephalogram (EEG) suggestive of interictal epileptiform discharges without any clinical seizures. The patient had very high titres of anti-thyroid peroxidase antibodies >2000 IU/mL and was on very high-dose levothyroxine replacement therapy. She responded to intravenous pulse corticosteroids. Improvement was noted both clinically and on subsequent EEGs. Pure cerebellar syndrome without frank encephalopathy can also be a rare presentation of Hashimoto encephalopathy. This highlights the importance of antithyroid antibodies testing even in cases of pure cerebellar syndrome to rule out Hashimoto encephalopathy associated ataxia.


Assuntos
Doenças Cerebelares , Encefalite , Doença de Hashimoto , Humanos , Doença de Hashimoto/complicações , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/tratamento farmacológico , Feminino , Encefalite/diagnóstico , Encefalite/complicações , Adulto , Doenças Cerebelares/diagnóstico , Doenças Cerebelares/tratamento farmacológico , Doenças Cerebelares/etiologia , Eletroencefalografia , Tiroxina/uso terapêutico , Tiroxina/administração & dosagem , Diagnóstico Diferencial
6.
Acta Radiol ; : 2841851241254746, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38803154

RESUMO

BACKGROUND: Alzheimer's disease (AD) and frontotemporal dementia (FTD) require different treatments. Since clinical presentation can be nuanced, imaging biomarkers aid in diagnosis. Automated software such as Neuroreader (NR) provides volumetric imaging data, and indices between anterior and posterior brain areas have proven useful in distinguishing dementia subtypes in research cohorts. Existing indices are complex and require further validation in clinical settings. PURPOSE: To provide initial validation for a simplified anterior-posterior index (API) from NR in distinguishing FTD and AD in a clinical cohort. MATERIAL AND METHODS: A retrospective chart review was completed. We derived a simplified API: API = (logVA/VP-µ)/σ where VA is weighted volume of frontal and temporal lobes and VP of parietal and occipital lobes. µ and σ are the mean and standard deviation of logVA/VP computed for AD participants. Receiver operating characteristic (ROC) curves and regression analyses assessed the efficacy of the API versus brain areas in predicting diagnosis of AD versus FTD. RESULTS: A total of 39 participants with FTD and 78 participants with AD were included. The API had an excellent performance in distinguishing AD from FTD with an area under the ROC curve of 0.82 and a positive association with diagnostic classification on logistic regression analysis (B = 1.491, P < 0.001). CONCLUSION: The API successfully distinguished AD and FTD with excellent performance. The results provide preliminary validation of the API in a clinical setting.

7.
Children (Basel) ; 11(5)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38790506

RESUMO

In newborns, white matter shows a high T2-weighted (T2w) signal in MRI with poor grey-white matter contrast. To increase this contrast, an extremely long echo time (TE) is used in the examination of children. It is not known up to what age this long TE should be used. The purpose of this study was to find up to what age a long TE should be used in infants. In the prospective study, 101 infants (0-18 months) underwent cranial MRI at 3 Tesla. T2-weighted Fast Spin Echo sequences with long TE (200 ms) and medium TE (100 ms) were used. The signal intensities of the cortex and white matter were measured and the grey-white matter contrast (MC) was calculated. A cut-off age was determined. The T2w sequences with long TE had a statistically significantly higher MC until the age of six months (medium TE: 0.1 ± 0.05, Long TE: 0.19 ± 0.07; p < 0.001). After the tenth month, the T2w sequence with medium TE provided significantly better MC (Medium TE: 0.1 ± 0.05; long TE: 0.05 ± 0.4; p < 0.001). The use of a long TE is only helpful in the first six months of life. After the tenth month of life, a medium TE should be favored as is used in adult brain MRI.

8.
Malays J Med Sci ; 31(2): 62-71, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38694577

RESUMO

Background: Auditory brainstem response (ABR) to the level-specific (LS) CE-Chirp has been reported to provide optimum neural synchrony along cochlear partitions, theoretically improving ABR waveform resolution. Despite this promising finding, limited studies have been conducted to contrast the results between LS CE-Chirp and Click stimuli. The current study aimed to compare the results of ABR between the two stimuli (Click and LS CE-Chirp). Method: Sixty-seven normal-hearing infants, both with and without risk factors, aged less than 7 months old, participated in this study. The ABR test was conducted at 70 dBnHL using 33.3 stimulus repetition rates with both Click and LS CE-Chirp stimuli. The signal averaging was stopped at a maximum fixed signal average of 2,500 sweeps. Data were statistically compared between the two stimuli using the Wilcoxon signed-rank test. Results: The waves I and V ABRs elicited by LS CE-Chirp exhibited significantly larger amplitudes than the Click stimulus. However, the amplitude of wave III and absolute latencies were similar in both stimuli at a supra-threshold level. Conclusion: LS CE-Chirp has the advantage of larger amplitudes than the ABR from Click at the supra-threshold level (70 dBnHL) in normal-hearing infants.

9.
BMJ Case Rep ; 17(4)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38688573

RESUMO

A middle-aged man with progressive multifocal leukoencephalopathy (PML) in a human T-cell lymphotropic virus type-1 (HTLV-1) carrier on haemodialysis presented with mild dysarthria and ataxia. Brain MRI revealed asymmetric T2-hyperintense lesions in the cerebral white matter, cerebellum and brainstem. A small amount of JC virus (JCV) genome in cerebrospinal fluid was detected by PCR and cerebellar biopsy demonstrated JCV-DNA presence. Pathological findings showed demyelinating lesions and glial cells with mildly enlarged nuclei, accompanied by T-lymphocytes, neutrophils and plasma cell infiltration. The CD4+/CD8+ratio was 0.83. High-dose corticosteroid therapy was effective for inflammatory PML lesions, and the administration of mefloquine combined with mirtazapine led to favourable outcome. The encephalitis in this case is considered to have occurred secondarily to JCV infection in the presence of HTLV-1 infection. Therefore, it is crucial to investigate the presence of HTLV-1 in order to understand the aetiology of this brain inflammation.


Assuntos
Coinfecção , Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Vírus JC , Leucoencefalopatia Multifocal Progressiva , Mirtazapina , Humanos , Leucoencefalopatia Multifocal Progressiva/virologia , Leucoencefalopatia Multifocal Progressiva/tratamento farmacológico , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Masculino , Infecções por HTLV-I/complicações , Infecções por HTLV-I/tratamento farmacológico , Infecções por HTLV-I/diagnóstico , Pessoa de Meia-Idade , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Vírus JC/isolamento & purificação , Mirtazapina/uso terapêutico , Imageamento por Ressonância Magnética , Mefloquina/uso terapêutico
10.
J Family Med Prim Care ; 13(2): 517-523, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38605746

RESUMO

Introduction: Hearing loss is a global issue of hearing disability and early detection and rehabilitation of hearing loss are important for the development of speech and language skills in hearing-impaired infants. There are multiple risk factors that aid in hearing loss but some are potential factors that contribute toward hearing loss in infants. The aim of this study was to assess the burden of hearing loss and its correlation with risk factors among high-risk infants at a teaching institution in Jaipur, Rajasthan. Method: This study was carried out after approval of institutional ethics committee on a total of 320 high-risk infants at RUHS College of medical sciences and associated hospitals. Hearing loss was assessed by brainstem evoked response audiometry (BERA). Statistical analysis of data was done by cross-tabulation analysis with Pearson correlation and quantile regression. Results: Out of 320 high-risk infants, 59.69% of infants had normal hearing, 9.09% Unilaterally hearing impaired, 20.31% were bilaterally mild-moderate hearing loss, and 10.94% had severe-profound deafness. The prevalence of important risk factors viz. hyperbilirubinemia, low birth weight, appearance, pulse, grimace, activity, and respiration score, meconium aspiration, respiratory distress, and ventilation greater than five days were 86%, 58.9%, 40%, 36%, 29%, and 22%, respectively. Conclusion: In high-risk infants, hearing loss is a common hearing disorder. Because of this, early diagnosis of hearing loss gives them the best chance of developing functional speech. Brainstem evoked response audiometry is a simple, reliable, and effective technique for the assessment of auditory functions in infants.

11.
Front Pediatr ; 12: 1370843, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650992

RESUMO

Background: Catastrophic antiphospholipid syndrome (CAPS) is a multi-system autoimmune disease characterized by extensive thrombosis. Pediatric CAPS is extremely rare and associated with a high mortality rate, especially when midbrain infarction is involved. Hence, early diagnosis and prompt initiation of appropriate treatment for CAPS complicated by midbrain infarction are of utmost importance in achieving favorable outcomes. Case presentation: In this report, we present the case of a 14-year-old girl who presented with neurological symptoms and digestive system infection and was initially diagnosed with an "intracranial infection". After a series of rigorous diagnostic procedures, the patient was ultimately diagnosed with primary CAPS and was immediately transferred to the intensive care unit where she was treated with anticoagulation, glucocorticoids, intravenous immunoglobulin (IVIG) therapy, and multiple plasma infusions. Twenty-seven days after admission, the patient's condition improved with standardized treatment, and she was discharged and followed up regularly. Conclusion: This case report provides a description of the clinical features observed in a pediatric patient with CAPS and concurrent midbrain infarction, highlighting the crucial role of early diagnosis and timely treatment in influencing patient prognosis.

12.
Folia Phoniatr Logop ; : 1-15, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615664

RESUMO

INTRODUCTION: Speech sound disorder (SSD) is a speech and language disorder associated with difficulties in motor production, perception, and phonological representation of sounds and speech segments. Since auditory perception has a fundamental role in forming and organizing sound representation for its recognition, studies that evaluate the cortical processing of sounds are required. Thus, the present study aimed to verify the relation between SSD severity measured by the percentage of correct consonants (PCCs) with the cortical auditory evoked potentials (CAEPs) using speech stimulus. METHODS: Twenty-nine children with normal hearing participated in this research and were grouped into three groups by SSD level measured by the PCC index. In addition, the groups were subdivided according to the children's age group: between 60-71 months, 72-83 months, and 83-94 months. The CAEP with speech stimulus was carried out in all children. RESULTS: Older children had longer P1 and N1 latencies. In P2 latency, there was an interference of age only in the severe group. The N2 latency was affected by age, where older children had longer latency. CONCLUSION: The amplitude of CAEP has not suffered any interference with the age, or severity of SSD. For the latency, older children generally presented longer averages than younger ones.

13.
BMJ Case Rep ; 17(4)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627057

RESUMO

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a recently described chronic inflammatory central nervous system disease. This case report describes a young female patient presenting with weakness in bilateral upper and lower limbs and tinnitus for 2 months. A neurological examination revealed signs of brainstem and cerebellar involvement. MRI brain showed characteristic features of CLIPPERS, with punctate and nodular enhancement in the pons and cerebellum. Differential diagnoses were systematically considered and excluded. The patient showed significant clinical and radiological improvement with steroid therapy. No clinical or radiological red flags occurred during the follow-up. This case underscores the critical role of integrating clinical and radiological findings to effectively diagnose and manage CLIPPERS. It emphasises the importance of ruling out alternative diagnoses through a thorough evaluation.


Assuntos
Doenças do Sistema Nervoso Central , Inflamação , Humanos , Feminino , Inflamação/diagnóstico , Ponte/diagnóstico por imagem , Tronco Encefálico/diagnóstico por imagem , Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/diagnóstico por imagem , Esteroides/uso terapêutico , Imageamento por Ressonância Magnética
14.
BMJ Case Rep ; 17(4)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38670569

RESUMO

Facial paralysis presents as unilateral mouth drooping and lagophthalmos. The main causes of peripheral facial paralysis are Bell's palsy and Ramsay-Hunt syndrome. However, rarely occurring pontine infarctions of the facial nucleus also manifest a lower motor neuron pattern of facial paralysis. We report a case of a man in his 50s who presented to the emergency department with unilateral peripheral facial paralysis. The initial diffusion-weighted images were unremarkable, and the patient was managed as per guidelines for hypertensive encephalopathy or Bell's palsy. On the 3rd day after admission, he was diagnosed with left pontine infarction and suspected infarction of the left anterior inferior cerebellar artery. We propose that in similar cases, re-examination of imaging results should be considered, as diffusion-weighted imaging is characteristically prone to generate false-negative results in patients with early onset or posterior circulation infarction.


Assuntos
Infartos do Tronco Encefálico , Paralisia Facial , Humanos , Masculino , Paralisia Facial/etiologia , Pessoa de Meia-Idade , Infartos do Tronco Encefálico/complicações , Infartos do Tronco Encefálico/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Tegmento Pontino/diagnóstico por imagem , Ponte/diagnóstico por imagem , Ponte/irrigação sanguínea , Ponte/patologia , Diagnóstico Diferencial
15.
Indian J Otolaryngol Head Neck Surg ; 76(2): 1741-1746, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566699

RESUMO

Introduction: Gestational diabetes is a potential risk factor for neonatal hearing loss. Increased circulating sugars in mothers during pregnancy can impairs the micro circulation and can cause congenital anomalies of the inner ear resulting in congenital hearing loss. This study attempts to find the incidence of neonatal hearing loss among diabetic mothers. Methodology: This was a case control study with 86 neonates of diabetic mothers as cases and neonates of non diabetic mothers(n = 86) as controls. Antenatal diabetic history and sugar values of mothers were documented. Hearing status of the neonates were tested using DPOAE test and ABR test. DPOAE test was done on 3rd day and those who did not get a positive response underwent 2nd DPOAE and also ABR test if 2nd DPOAE was negative. Results: All neonates underwent DPOAE test and few were lost on follow up. First and second DPOAE showed a statistically significant difference between cases and controls. All babies who underwent ABR test had abnormal waveforms. 98% of cases showed moderate and severe bilateral hearing loss whereas all controls had only mild bilateral hearing loss. Discussion: This study showed a significantly higher percentage of abnormal hearing outcome among neonates of diabetic mothers than non diabetic mothers. This could be because of the toxic effects of maternal hyperglycemia on developing auditory system of the fetus. This study emphasis the need for better glycaemic control in diabetic pregnancy, the importance of early and mandatory hearing screening in newborns of diabetic mothers.

16.
Radiol Artif Intell ; 6(3): e230333, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38446044

RESUMO

Purpose To develop and externally test a scan-to-prediction deep learning pipeline for noninvasive, MRI-based BRAF mutational status classification for pediatric low-grade glioma. Materials and Methods This retrospective study included two pediatric low-grade glioma datasets with linked genomic and diagnostic T2-weighted MRI data of patients: Dana-Farber/Boston Children's Hospital (development dataset, n = 214 [113 (52.8%) male; 104 (48.6%) BRAF wild type, 60 (28.0%) BRAF fusion, and 50 (23.4%) BRAF V600E]) and the Children's Brain Tumor Network (external testing, n = 112 [55 (49.1%) male; 35 (31.2%) BRAF wild type, 60 (53.6%) BRAF fusion, and 17 (15.2%) BRAF V600E]). A deep learning pipeline was developed to classify BRAF mutational status (BRAF wild type vs BRAF fusion vs BRAF V600E) via a two-stage process: (a) three-dimensional tumor segmentation and extraction of axial tumor images and (b) section-wise, deep learning-based classification of mutational status. Knowledge-transfer and self-supervised approaches were investigated to prevent model overfitting, with a primary end point of the area under the receiver operating characteristic curve (AUC). To enhance model interpretability, a novel metric, center of mass distance, was developed to quantify the model attention around the tumor. Results A combination of transfer learning from a pretrained medical imaging-specific network and self-supervised label cross-training (TransferX) coupled with consensus logic yielded the highest classification performance with an AUC of 0.82 (95% CI: 0.72, 0.91), 0.87 (95% CI: 0.61, 0.97), and 0.85 (95% CI: 0.66, 0.95) for BRAF wild type, BRAF fusion, and BRAF V600E, respectively, on internal testing. On external testing, the pipeline yielded an AUC of 0.72 (95% CI: 0.64, 0.86), 0.78 (95% CI: 0.61, 0.89), and 0.72 (95% CI: 0.64, 0.88) for BRAF wild type, BRAF fusion, and BRAF V600E, respectively. Conclusion Transfer learning and self-supervised cross-training improved classification performance and generalizability for noninvasive pediatric low-grade glioma mutational status prediction in a limited data scenario. Keywords: Pediatrics, MRI, CNS, Brain/Brain Stem, Oncology, Feature Detection, Diagnosis, Supervised Learning, Transfer Learning, Convolutional Neural Network (CNN) Supplemental material is available for this article. © RSNA, 2024.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Criança , Masculino , Feminino , Neoplasias Encefálicas/diagnóstico por imagem , Estudos Retrospectivos , Proteínas Proto-Oncogênicas B-raf/genética , Glioma/diagnóstico , Aprendizado de Máquina
17.
Radiol Artif Intell ; 6(3): e230151, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38506619

RESUMO

Purpose To develop a fast and fully automated deep learning (DL)-based method for the MRI planimetric segmentation and measurement of the brainstem and ventricular structures most affected in patients with progressive supranuclear palsy (PSP). Materials and Methods In this retrospective study, T1-weighted MR images in healthy controls (n = 84) were used to train DL models for segmenting the midbrain, pons, middle cerebellar peduncle (MCP), superior cerebellar peduncle (SCP), third ventricle, and frontal horns (FHs). Internal, external, and clinical test datasets (n = 305) were used to assess segmentation model reliability. DL masks from test datasets were used to automatically extract midbrain and pons areas and the width of MCP, SCP, third ventricle, and FHs. Automated measurements were compared with those manually performed by an expert radiologist. Finally, these measures were combined to calculate the midbrain to pons area ratio, MR parkinsonism index (MRPI), and MRPI 2.0, which were used to differentiate patients with PSP (n = 71) from those with Parkinson disease (PD) (n = 129). Results Dice coefficients above 0.85 were found for all brain regions when comparing manual and DL-based segmentations. A strong correlation was observed between automated and manual measurements (Spearman ρ > 0.80, P < .001). DL-based measurements showed excellent performance in differentiating patients with PSP from those with PD, with an area under the receiver operating characteristic curve above 0.92. Conclusion The automated approach successfully segmented and measured the brainstem and ventricular structures. DL-based models may represent a useful approach to support the diagnosis of PSP and potentially other conditions associated with brainstem and ventricular alterations. Keywords: MR Imaging, Brain/Brain Stem, Segmentation, Quantification, Diagnosis, Convolutional Neural Network Supplemental material is available for this article. © RSNA, 2024 See also the commentary by Mohajer in this issue.


Assuntos
Tronco Encefálico , Aprendizado Profundo , Imageamento por Ressonância Magnética , Paralisia Supranuclear Progressiva , Humanos , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/patologia , Imageamento por Ressonância Magnética/métodos , Feminino , Estudos Retrospectivos , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/patologia , Masculino , Idoso , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/patologia , Interpretação de Imagem Assistida por Computador/métodos
18.
Exp Neurobiol ; 33(1): 18-24, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38471801

RESUMO

Panic disorder (PD), characterized by recurrent and intense panic attacks, presents a complex interplay between psychological and neurobiological factors. Although the amygdala and hippocampus have been studied extensively in the context of PD, the brainstem's involvement remains relatively underexplored. This study aims to address this gap by examining structural abnormalities within specific brainstem regions, including the medulla, pons, and midbrain. The study sample population comprised twenty-one adult patients diagnosed with PD and an age-gender-education-matched control group. Utilizing rigorous inclusion and exclusion criteria, confounding factors related to comorbid psychiatric conditions and brain structure abnormalities were minimized. Our findings revealed a significant reduction in medulla volume among PD patients, a finding that persisted even after correcting for individual differences in total intracranial volume. The medulla's role in cardiovascular regulation and autonomic function, coupled with its involvement in fear responses, underscores its potential significance in the pathophysiology of PD. This study elucidates the medulla's structural abnormalities as a potential biomarker for PD. Understanding the role of the brainstem in PD could pave the way for more targeted and effective interventions for this condition.

19.
Stroke ; 55(5): 1151-1160, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38529636

RESUMO

BACKGROUND: Symptomatic brainstem cavernous malformations (BSCMs) pose a high risk of morbidity and mortality due to recurrent hemorrhage, warranting aggressive management. However, few studies have compared the effectiveness of different treatment modalities for BSCMs. We aimed to assess the association of treatment modalities with recurrent hemorrhage and neurological outcomes in patients with BSCM. METHODS: We conducted a retrospective cohort study using an observational registry database covering population of southwest and southeast China. Adult patients with BSCM were included and followed up between March 1, 2011, to March 31, 2023. We compared outcomes between microsurgery and stereotactic radiosurgery (SRS) in propensity score-matched case pairs, incorporating demographic, medical history, and lesion characteristics. The outcomes studied included recurrent hemorrhage and poor prognosis (defined as a Glasgow Outcome Scale score, <4). Absolute rate differences and hazard ratios (HRs) with 95% CIs were calculated using Cox models. RESULTS: Among 736 diagnosed patients with BSCM, 96 (48 matched pairs) were included after exclusions and propensity score matching (mean age, 43.1 [SD, 12.1] years; 50% women). During the median 5-year follow-up, no significant differences in recurrent hemorrhage (4.2% [microsurgery] versus 14.6% [SRS], HR, 3.90 [95% CI, 0.46-32.65]; P=0.21) and poor prognosis (12.5% [microsurgery] versus 8.3% [SRS], HR, 0.29 [95% CI, 0.08-1.08]; P=0.07) were observed between microsurgery and SRS recipients. Furthermore, either microsurgery or SRS correlated with fewer recurrent hemorrhage (HR, 0.09 [95% CI, 0.02-0.39]; P=0.001; HR, 0.21 [95% CI, 0.07-0.69]; P=0.01) compared with conservative treatment. CONCLUSIONS: In this study, both microsurgery and SRS were safe and effective for BSCM, demonstrated comparable outcomes in recurrent hemorrhage and poor prognosis. However, interpretation should be cautious due to the potential for residual confounding. REGISTRATION: URL: https://www.chictr.org.cn/; Unique identifier: ChiCTR2300070907.

20.
Case Rep Oncol ; 17(1): 504-510, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38549623

RESUMO

Introduction: Intracranial germinomas mainly arise in the pineal gland or neurohypophyseal region. The basal ganglia have been reported as the site of occurrence for ectopic germinomas, whereas other sites have been rarely described. We experienced a case of multifocal ectopic germinoma that arose in the septum pellucidum and the dorsal brain stem, not including the pineal gland, neurohypophysis, and basal ganglia of ectopic germinoma in a pregnant woman. Case Presentation: The patient initially presented to our institution with complaints of diplopia in the past 14 weeks of gestation, and imaging later revealed two intracranial neoplastic lesions, with one lesion involving the septum pellucidum and the other involving the dorsal brainstem. Both tumors were partially excised via a transcortical approach. Based on the results of pathology and immunohistochemistry, the patient was diagnosed with germinoma, and the intraoperative spinal fluid cytology was class V in Papanicolaou classification. The patient received three courses of ifosfamide, carboplatin, and etoposide together with whole-brain irradiation, which resulted in complete elimination of the tumors. No evidence of recurrence was identified after 18 months. Conclusion: The results illustrated the need to consider germinoma in the differential diagnosis if the lesions involve midline structures such as the septum pellucidum or dorsal brainstem. Given the rarity of germinoma arising outside the pineal gland and neurohypophyseal region, these findings provide key insights into the diagnosis and treatment of this disease.

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