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2.
J Clin Neurosci ; 123: 194-195, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38599033

RESUMEN

A 29-year-old gentleman diagnosed with Rosai-Dorfman disease (RDD) on corneal biopsy, 2 years ago, presented with fluctuating left-sided numbness, intermittent slurred speech, and urinary incontinence, progressively worsening over the past three months.


Asunto(s)
Histiocitosis Sinusal , Humanos , Histiocitosis Sinusal/patología , Histiocitosis Sinusal/diagnóstico , Masculino , Adulto , Imagen por Resonancia Magnética
4.
Magn Reson Imaging Clin N Am ; 32(2): 347-361, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38555145

RESUMEN

Atypical infections of the brain and spine caused by parasites occur in immunocompetent and immunosuppressed hosts, related to exposure and more prevalently in endemic regions. In the United States, the most common parasitic infections that lead to central nervous system manifestations include cysticercosis, echinococcosis, and toxoplasmosis, with toxoplasmosis being the most common opportunistic infection affecting patients with advanced HIV/AIDS. Another rare but devastating transmittable disease is prion disease, which causes rapidly progressive spongiform encephalopathies. Familiarity and understanding of various infectious agents are a crucial aspect of diagnostic neuroradiology, and recognition of unique features can aid timely diagnosis and treatment.


Asunto(s)
Enfermedades Transmisibles , Encefalopatía Espongiforme Bovina , Parásitos , Enfermedades por Prión , Toxoplasmosis , Animales , Bovinos , Humanos , Encefalopatía Espongiforme Bovina/diagnóstico , Imagen por Resonancia Magnética/métodos , Enfermedades por Prión/diagnóstico , Encéfalo/diagnóstico por imagen
5.
Magn Reson Imaging Clin N Am ; 32(2): 335-346, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38555144

RESUMEN

Advances in treatments of autoimmune diseases, acquired immunodeficiency syndrome, organ transplantation, and the use of long-term devices have increased the rates of atypical infections due to prolonged immune suppression. There is a significant overlap in imaging findings of various fungal infections affecting the central nervous system (CNS), often mimicking those seen in neoplastic and noninfectious inflammatory conditions. Nonetheless, there are imaging characteristics that can aid in distinguishing certain atypical infections. Hence, familiarity with a wide range of infectious agents is an important part of diagnostic neuroradiology. In this article, an in-depth review of fungal diseases of the CNS is provided.


Asunto(s)
Enfermedades Transmisibles , Micosis , Humanos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Columna Vertebral , Micosis/diagnóstico por imagen
6.
Artículo en Inglés | MEDLINE | ID: mdl-38360789

RESUMEN

BACKGROUND: Neoplasms derived from the sinonasal epithelium are a rare finding in the temporal bone, and their origins are controversial. PURPOSE: To review the characteristics of sinonasal epithelial (previously known as Schneiderian) tumors occurring in the temporal bone. DATA SOURCE: This was a 2-center case series and systematic review of MEDLINE, EMBASE, and the Web of Science through May 2021. STUDY SELECTION: Patients with clinicopathologic evidence of temporal bone involvement by neoplasms of sinonasal epithelial origin were selected, with or without a history of prior primary sinonasal epithelial tumors. DATA ANALYSIS: Clinical, radiologic, and pathologic data were extracted. DATA SYNTHESIS: The systematic review included 56 studies and our 8 unpublished cases, totaling 76 cases of papillomas or squamous cell carcinomas in the temporal bone. Of these, 51% occurred secondary to sinonasal tumors, and 49% occurred primarily. Secondary tumors were usually metachronous (77%), with a median delay of 1 year from sinonasal-to-temporal bone tumor diagnosis. Most cases were unilateral (90%); bilateral temporal bone involvement occurred only as secondary ("trilateral") tumors. Unilateral secondary tumors had ipsilateral (81%) or bilateral (19%) sinonasal counterparts. Secondary tumors were more likely to be malignant (OR, 6.7, P < .001). LIMITATIONS: The review was based on case reports and small case series, which are subject to reporting bias. CONCLUSIONS: The observed tumor patterns support the hypothesis that the Eustachian tube facilitates the spread of sinonasal epithelium-derived neoplasms from the sinonasal cavity to the temporal bone. Transtubal spread of sinonasal epithelium-derived neoplasms should be considered among the rare causes of middle ear masses.

7.
Acad Radiol ; 31(4): 1572-1582, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37951777

RESUMEN

RATIONALE AND OBJECTIVES: Brain tumor segmentations are integral to the clinical management of patients with glioblastoma, the deadliest primary brain tumor in adults. The manual delineation of tumors is time-consuming and highly provider-dependent. These two problems must be addressed by introducing automated, deep-learning-based segmentation tools. This study aimed to identify criteria experts use to evaluate the quality of automatically generated segmentations and their thought processes as they correct them. MATERIALS AND METHODS: Multiple methods were used to develop a detailed understanding of the complex factors that shape experts' perception of segmentation quality and their thought processes in correcting proposed segmentations. Data from a questionnaire and semistructured interview with neuro-oncologists and neuroradiologists were collected between August and December 2021 and analyzed using a combined deductive and inductive approach. RESULTS: Brain tumors are highly complex and ambiguous segmentation targets. Therefore, physicians rely heavily on the given context related to the patient and clinical context in evaluating the quality and need to correct brain tumor segmentation. Most importantly, the intended clinical application determines the segmentation quality criteria and editing decisions. Physicians' personal beliefs and preferences about the capabilities of AI algorithms and whether questionable areas should not be included are additional criteria influencing the perception of segmentation quality and appearance of an edited segmentation. CONCLUSION: Our findings on experts' perceptions of segmentation quality will allow the design of improved frameworks for expert-centered evaluation of brain tumor segmentation models. In particular, the knowledge presented here can inspire the development of brain tumor-specific metrics for segmentation model training and evaluation.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Adulto , Humanos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Algoritmos , Glioblastoma/patología , Reconocimiento de Normas Patrones Automatizadas/métodos , Carga Tumoral , Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador/métodos
8.
J Neuroimaging ; 33(1): 44-57, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36207276

RESUMEN

Stroke mimics constitute a significant proportion of patients with suspected acute ischemic stroke. These conditions may resemble acute ischemic stroke and demonstrate abnormalities on perfusion imaging sequences. The most common stroke mimics include seizure/epilepsy, migraine with aura, brain tumors, functional disorders, infectious encephalopathies, Wernicke's encephalopathy, and metabolic abnormalities. Brain perfusion imaging techniques, particularly computed tomography perfusion and magnetic resonance perfusion, are being widely used in routine clinical practice for treatment selection in patients presenting with large vessel occlusion. At the same time, the utilization of these imaging modalities enables the opportunity to better diagnose patients with stroke mimics in a time-sensitive setting, leading to appropriate management, decision-making, and resource allocation. In this review, we describe patterns of perfusion abnormalities that could discriminate patients with stroke mimics from those with acute ischemic stroke and provide specific case examples to illustrate these perfusion abnormalities. In addition, we discuss the challenges associated with interpretation of perfusion images in stroke-related pathologies. In general, perfusion imaging can provide additional information in some cases-when used in combination with conventional magnetic resonance imaging and computed tomography-and might help in detecting stroke mimics among patients who present with acute onset focal neurological symptoms.


Asunto(s)
Isquemia Encefálica , Epilepsia , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular/complicaciones , Encéfalo/diagnóstico por imagen , Isquemia Encefálica/complicaciones , Imagen de Perfusión/métodos
9.
Neuroradiol J ; 36(6): 638-650, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36172883

RESUMEN

Arterial spin labeling (ASL) is a magnetic resonance perfusion technique that allows for quantification of cerebral blood flow (CBF) without the use of contrast or radiation. Several applications of ASL have been described in diagnosis of strokes and stroke mimics, intracranial tumors, and other conditions. Various vascular anomalies exhibit specific CBF patterns that correlate with different signal intensities on ASL. In this case-based review, we demonstrate the utility of ASL in diagnosis and surveillance of vascular anomalies in the intracranial compartment.


Asunto(s)
Neoplasias Encefálicas , Anomalías Cardiovasculares , Accidente Cerebrovascular , Malformaciones Vasculares , Humanos , Angiografía por Resonancia Magnética/métodos , Marcadores de Spin , Imagen por Resonancia Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Circulación Cerebrovascular
10.
AJR Am J Roentgenol ; 220(1): 141-142, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35822643

RESUMEN

To evaluate for differences in breast cancer screening among women with visual or hearing impairment, the 2019 National Health Interview Survey was analyzed for mammography use in the past 2 years among women age 50-74, adjusting for demographic characteristics, health care access, and comorbidities. Visual impairment was independently associated with decreased likelihood of recent mammography (odds ratio [OR], 0.71; 95% CI, 0.59-0.85; p < .001). Hearing impairment was not independently associated with mammography use (OR, 0.91; 95% CI, 0.75-1.11; p = .37).


Asunto(s)
Neoplasias de la Mama , Mamografía , Femenino , Humanos , Persona de Mediana Edad , Anciano , Neoplasias de la Mama/diagnóstico por imagen , Detección Precoz del Cáncer , Encuestas y Cuestionarios , Audición , Tamizaje Masivo/métodos
11.
Neuroradiol J ; 36(2): 129-141, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35815750

RESUMEN

Arterial spin labeling (ASL) is a noninvasive neuroimaging technique that allows for quantifying cerebral blood flow without intravenous contrast. Various neurovascular disorders and tumors have cerebral blood flow alterations. Identifying these perfusion changes through ASL can aid in the diagnosis, especially in entities with normal structural imaging. In addition, complications of tumor treatment and tumor progression can also be monitored using ASL. In this case-based review, we demonstrate the clinical applications of ASL in diagnosing and monitoring brain tumors and treatment complications.


Asunto(s)
Neoplasias Encefálicas , Angiografía por Resonancia Magnética , Humanos , Marcadores de Spin , Angiografía por Resonancia Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/irrigación sanguínea , Neuroimagen/métodos , Circulación Cerebrovascular , Imagen por Resonancia Magnética/métodos
13.
Otolaryngol Head Neck Surg ; 167(2): 268-273, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34609936

RESUMEN

OBJECTIVE: There is concern that current otolaryngology residents may not receive adequate surgical training. We aimed to characterize residents' surgical experiences at 5 academic centers performing the 14 key indicator procedures (KIPs) outlined by the Accreditation Council for Graduate Medical Education. STUDY DESIGN: Prospective study. SETTING: Five otolaryngology training programs. METHODS: Data were gathered from December 2019 to December 2020 with a smartphone application from the Society for Improving Medical Professional Learning. After each operation, residents and faculty rated trainee autonomy on a 4-level Zwisch scale and performance on a 5-level modified Dreyfus scale. RESULTS: Residents and attendings (n = 92 and 78, respectively) logged 2984 evaluations. Attending ratings of resident autonomy and performance increased with training level (P < .001). Resident self-assessments of autonomy and performance were lower than paired attending assessments (P < .001). Among attending evaluations of KIPs performed by senior residents (postgraduate year 4 or 5), 55% of cases were performed with meaningful autonomy (passive help or supervision only). Similarly, attendings rated 55% of these cases as a practice-ready or exceptional performance. Senior residents had meaningful autonomy for ≥50% of cases for most KIPs, with the exception of flaps and grafts (40%), pediatric/adult airway (39%), and stapedectomy/ossiculoplasty (33%). Similarly, senior residents received practice-ready or exceptional performance ratings for ≥50% of cases across all KIPs other than pediatric/adult airway (42%) and stapedectomy/ossiculoplasty (33%). CONCLUSION: In this multicenter study, resident surgical autonomy and performance varied across otolaryngology KIPs. The development of nationwide benchmarks will help programs and residents set educational goals. LEVEL OF EVIDENCE: 2.


Asunto(s)
Cirugía General , Internado y Residencia , Otolaringología , Adulto , Niño , Competencia Clínica , Educación de Postgrado en Medicina/métodos , Cirugía General/educación , Humanos , Otolaringología/educación , Autonomía Profesional , Estudios Prospectivos
14.
Acad Radiol ; 29(4): 479-487, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-33583713

RESUMEN

RATIONALE AND OBJECTIVES: Train and apply natural language processing (NLP) algorithms for automated radiology-arthroscopy correlation of meniscal tears. MATERIALS AND METHODS: In this retrospective single-institution study, we trained supervised machine learning models (logistic regression, support vector machine, and random forest) to detect medial or lateral meniscus tears on free-text MRI reports. We trained and evaluated model performances with cross-validation using 3593 manually annotated knee MRI reports. To assess radiology-arthroscopy correlation, we then randomly partitioned this dataset 80:20 for training and testing, where 108 test set MRIs were followed by knee arthroscopy within 1 year. These free-text arthroscopy reports were also manually annotated. The NLP algorithms trained on the knee MRI training dataset were then evaluated on the MRI and arthroscopy report test datasets. We assessed radiology-arthroscopy agreement using the ensembled NLP-extracted findings versus manually annotated findings. RESULTS: The NLP models showed high cross-validation performance for meniscal tear detection on knee MRI reports (medial meniscus F1 scores 0.93-0.94, lateral meniscus F1 scores 0.86-0.88). When these algorithms were evaluated on arthroscopy reports, despite never training on arthroscopy reports, performance was similar, though higher with model ensembling (medial meniscus F1 score 0.97, lateral meniscus F1 score 0.99). However, ensembling did not improve performance on knee MRI reports. In the radiology-arthroscopy test set, the ensembled NLP models were able to detect mismatches between MRI and arthroscopy reports with sensitivity 79% and specificity 87%. CONCLUSION: Radiology-arthroscopy correlation can be automated for knee meniscal tears using NLP algorithms, which shows promise for education and quality improvement.


Asunto(s)
Radiología , Lesiones de Menisco Tibial , Artroscopía , Humanos , Imagen por Resonancia Magnética , Procesamiento de Lenguaje Natural , Estudios Retrospectivos , Sensibilidad y Especificidad , Máquina de Vectores de Soporte , Lesiones de Menisco Tibial/diagnóstico por imagen
15.
J Grad Med Educ ; 13(5): 666-672, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34721795

RESUMEN

BACKGROUND: Gender disparities are prevalent in medicine, but their impact on surgical training is not well studied. OBJECTIVE: To quantify gender disparities in trainee intraoperative experiences and explore the variables associated with ratings of surgical autonomy and performance. METHODS: From September 2015 to May 2019, attending surgeons and trainees from 71 programs assessed trainee autonomy on a 4-level Zwisch scale and performance on a 5-level modified Dreyfus scale after surgical procedures. Multivariable regression models were used to examine the association of trainee gender with autonomy and performance evaluations. RESULTS: A total of 3255 trainees and attending surgeons completed 94 619 evaluations. Attendings gave lower ratings of operative autonomy to female trainees than male trainees when controlling for training level, attending, and surgical procedure (effect size B = -0.0199, P = .008). There was no difference in ratings of autonomy at the beginning of training (P = .32); the gap emerged as trainees advanced in years (B = -0.0163, P = .020). The gender difference in autonomy was largest for the most complex cases (B = -0.0502, P = .002). However, there was no difference in attending ratings of surgical performance for female trainees compared to male trainees (B = -0.0124, P = .066). Female trainees rated themselves as having less autonomy and worse performance than males when controlling for training level, attending, procedure, case complexity, and attending ratings (autonomy B = -0.0669, P < .001; performance B = -0.0704, P < .001). CONCLUSIONS: While there was no significant difference in ratings of operative performance, a small difference between ratings of operative autonomy for female and male surgical trainees was identified.


Asunto(s)
Cirugía General , Internado y Residencia , Cirujanos , Competencia Clínica , Femenino , Cirugía General/educación , Humanos , Masculino , Quirófanos , Autonomía Profesional
18.
Clin Cancer Res ; 21(6): 1340-7, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25609068

RESUMEN

PURPOSE: Estrogen receptor (ER) targeting is key in management of receptor-positive breast cancer. Currently, there are no methods to optimize anti-ER therapy dosing. This study assesses the use of 16α-(18)F-fluoroestradiol ((18)F-FES) PET for fulvestrant dose optimization in a preclinical ER(+) breast cancer model. EXPERIMENTAL DESIGN: In vitro, (18)F-FES retention was compared with ERα protein expression (ELISA) and ESR1 mRNA transcription (qPCR) in MCF7 cells (ER(+)) after treatment with different fulvestrant doses. MCF7 xenografts were grown in ovariectomized nude mice and assigned to vehicle, low- (0.05 mg), medium- (0.5 mg), or high-dose (5 mg) fulvestrant treatment groups (5-7 per group). Two and 3 days after fulvestrant treatment, PET/CT was performed using (18)F-FES and (18)F-FDG, respectively. ER expression was assessed by immunohistochemistry, ELISA, and qPCR on xenografts. Tumor proliferation was assessed using Ki67 immunohistochemistry. RESULTS: In vitro, we observed a parallel graded reduction in (18)F-FES uptake and ER expression with increased fulvestrant doses, despite enhancement of ER mRNA transcription. In xenografts, ER expression significantly decreased with increased fulvestrant dose, despite similar mRNA expression and Ki67 staining among the treatment groups. We observed a significant dose-dependent reduction of (18)F-FES PET mean standardized uptake value (SUV(mean)) with fulvestrant treatment but no significant difference among the treatment groups in (18)F-FDG PET SUV(mean). CONCLUSIONS: We demonstrated that (18)F-FES uptake mirrors the dose-dependent changes in functional ER expression with fulvestrant resulting in ER degradation and/or blockade; these precede changes in tumor metabolism and proliferation. Quantitative (18)F-FES PET may be useful for tracking early efficacy of ER blockade/degradation and guiding ER-targeted therapy dosing in patients with breast cancer.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Estradiol/análogos & derivados , Estradiol/metabolismo , Antagonistas del Receptor de Estrógeno/farmacología , Receptores de Estrógenos/metabolismo , Animales , Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/diagnóstico por imagen , Línea Celular Tumoral , Estradiol/farmacología , Femenino , Fulvestrant , Humanos , Células MCF-7 , Ratones , Ratones Desnudos , Tomografía de Emisión de Positrones/métodos , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Bogotá, D.C; ONU; 2000. 6 p.
Monografía en Español | LILACS | ID: lil-279683

RESUMEN

La finalización del conflicto en Colombia es esencial para detener la tendencia al crecimiento en el número de personas desplazadas y obtener una solución durable para el enorme número de personas que perdieron sus raíces. Hasta ese entonces, exhorto al Gobierno de Colombia a que, con la ayuda de la comunidad internacional y las organizaciones no gubernamentales, aumente sus esfuerzos para proveer a los ciudadanos colombianos protección frente a desplazamientos arbitrarios, asistencia durante el desplazamiento, y soluciones efectivas para el retorno o la reintegración. Paralelamente, es crítico que se continuen los esfuerzos hacia la paz. En particular, doy la bienvenida al reconocimiento del Presidente Pastrana que el problema del desplazamiento debe ser un factor clave en el proceso de paz. Los desplazados internos han hecho avances impresionantes en organizarse y es importante que sus voces se hagan oir y sean escuchadas en el proceso de paz


Asunto(s)
Violencia , Colombia
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