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1.
Neuroradiology ; 65(9): 1381-1386, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37127720

RESUMEN

PURPOSE: To evaluate apparent pituitary gland enlargement in patients with Sanfilippo syndrome observed at our institution. METHODS: Twelve patients with Sanfilippo syndrome with brain MRI were studied. Anterior, posterior, and whole pituitary volumes were estimated using the prolate ellipsoid volume calculation method (π/6 × L × W × H). Convexity along the upper pituitary margin (Elster's grade) was also measured. These values were compared to two age- and sex-matched groups (normal controls and patients with Hurler syndrome) using one-way ANOVA followed by Tukey's post hoc analysis for multiple comparisons. RESULTS: In the Sanfilippo cohort, the mean whole pituitary volume was 529.9 mm, the mean anterior pituitary volume was 333.4 mm, and the mean posterior pituitary volume was 59.1 mm with Elster's grade of 4.2. In the control cohort, the mean whole pituitary volume was 217.4 mm, the mean anterior pituitary volume was 154.8 mm, and the mean posterior pituitary volume was 28.4 mm with Elster's grade of 2.5. In the Hurler syndrome cohort, the mean whole pituitary volume was 310.0 mm, the mean anterior pituitary volume was 178.2 mm, and the mean posterior pituitary volume was 35.4 mm with Elster's grade of 3.5. CONCLUSION: In our cohort of patients with Sanfilippo syndrome, whole, anterior, and posterior pituitary volumes and degree of convexity along the upper pituitary border were all significantly greater than controls. The cause of these morphological changes is unclear, as is clinical correlation of the findings.


Asunto(s)
Mucopolisacaridosis III , Mucopolisacaridosis I , Humanos , Hipófisis/diagnóstico por imagen
2.
J Magn Reson Imaging ; 51(2): 331-338, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31355502

RESUMEN

The need for a guidance document on MR safe practices arose from a growing awareness of the MR environment's potential risks and adverse event reports involving patients, equipment, and personnel. Initially published in 2002, the American College of Radiology White Paper on MR Safety established de facto industry standards for safe and responsible practices in clinical and research MR environments. The most recent version addresses new sources of risk of adverse events, increases awareness of dynamic MR environments, and recommends that those responsible for MR medical director safety undergo annual MR safety training. With regular updates to these guidelines, the latest MR safety concerns can be accounted for to ensure a safer MR environment where dangers are minimized. Level of Evidence: 1 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2020;51:331-338.


Asunto(s)
Imagen por Resonancia Magnética , Humanos
3.
Radiology ; 292(3): 509-518, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31310177

RESUMEN

Although 7-T MRI has recently received approval for use in clinical patient care, there are distinct safety issues associated with this relatively high magnetic field. Forces on metallic implants and radiofrequency power deposition and heating are safety considerations at 7 T. Patient bioeffects such as vertigo, dizziness, false feelings of motion, nausea, nystagmus, magnetophosphenes, and electrogustatory effects are more common and potentially more pronounced at 7 T than at lower field strengths. Herein the authors review safety issues associated with 7-T MRI. The rationale for safety concerns at this field strength are discussed as well as potential approaches to mitigate risk to patients and health care professionals.


Asunto(s)
Seguridad de Equipos/métodos , Imagen por Resonancia Magnética/instrumentación , Humanos , Medición de Riesgo
4.
Radiographics ; 39(6): 1672-1695, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31589567

RESUMEN

Toxic and metabolic brain disorders are relatively uncommon diseases that affect the central nervous system, but they are important to recognize as they can lead to catastrophic outcomes if not rapidly and properly managed. Imaging plays a key role in determining the most probable diagnosis, pointing to the next steps of investigation, and providing prognostic information. The majority of cases demonstrate bilateral and symmetric involvement of structures at imaging, affecting the deep gray nuclei, cortical gray matter, and/or periventricular white matter, and some cases show specific imaging manifestations. When an appropriate clinical situation suggests exogenous or endogenous toxic effects, the associated imaging pattern usually indicates a restricted group of diagnostic possibilities. Nonetheless, toxic and metabolic brain disorders in the literature are usually approached in the literature by starting with common causal agents and then reaching imaging abnormalities, frequently mixing many different possible manifestations. Conversely, this article proposes a systematic approach to address this group of diseases based on the most important imaging patterns encountered in clinical practice. Each pattern is suggestive of a most likely differential diagnosis, which more closely resembles real-world scenarios faced by radiologists. Basic pathophysiologic concepts regarding cerebral edemas and their relation to imaging are introduced-an important topic for overall understanding. The most important imaging patterns are presented, and the main differential diagnosis for each pattern is discussed. Online supplemental material is available for this article. ©RSNA, 2019.


Asunto(s)
Encefalopatías Metabólicas/diagnóstico por imagen , Imagen por Resonancia Magnética , Neuroimagen , Síndromes de Neurotoxicidad/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Edema Encefálico/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Tomografía Computarizada por Rayos X/métodos
6.
J Neurol Neurosurg Psychiatry ; 89(1): 14-20, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28794149

RESUMEN

Over two decades have passed since posterior reversible encephalopathy syndrome (PRES) was first described in 1996. It has becoming increasingly recognised because of improved and more readily available imaging modality. The exact pathophysiological mechanism is not completely understood and remains controversial at present. Precise diagnosis is essential to guide prompt, proper management. Our ability of differentiating it from other acute neurological disorders is likely to improve as we learnt more about the spectrum of this entity in the last 20 years. We emphasise the importance of recognising its diagnostic criteria and biomarker, which would be of great relevance to either outcome evaluation or study design. PRES has a favourable prognosis generally, but neurological sequelae and even fatalities can occur, especially in severe forms that might cause substantial morbidity and even mortality, particularly when the syndrome is complicated by intracranial haemorrhage or brain infarction. In this review, the pathophysiology, approach to diagnosis, some controversies as to the prognosis, as well as the future research direction of PRES are described.


Asunto(s)
Encéfalo/fisiopatología , Síndrome de Leucoencefalopatía Posterior/diagnóstico , Síndrome de Leucoencefalopatía Posterior/fisiopatología , Encéfalo/diagnóstico por imagen , Humanos , Síndrome de Leucoencefalopatía Posterior/diagnóstico por imagen , Pronóstico
7.
J Stroke Cerebrovasc Dis ; 27(4): 936-944, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29198948

RESUMEN

BACKGROUND: The information on topographic distribution of acute ischemic infarct can contribute to prediction of functional outcome. We aimed to develop a multivariate model for stroke prognostication, combining admission clinical and imaging variables, including the infarct topology. METHODS: Acute ischemic stroke patients without baseline functional disability who had magnetic resonance imaging within 24 hours of onset or last-seen-well were included. The admission stroke severity was determined using the National Institutes of Health Stroke Scale (NIHSS) score. The relation between infarct location and outcome was assessed using both voxel-based and visual atlas-based analyses. The disability/death was defined by a modified Rankin Scale score greater than 2 at 3-month follow-up. RESULTS: Among 198 patients included in this study, higher admission NIHSS score (P < .001), larger infarct volume (P < .001), and major arterial occlusions (P < .001) were associated with disability/death in univariate analyses. On voxel-based analysis, infarcts in the middle centrum semiovale, insula, and midbrain/pons were associated with higher rates of disability/death. In multivariate analysis, admission NIHSS score (P < .001), infarction of insula (P = .005), and midbrain/pons (P = .006) were independent predictors of disability/death. In receiver operating characteristics analysis, a simple 0-to-3 scoring system using these 3 variables had an area under the curve of .812 for prediction of disability/death (P < .001). CONCLUSIONS: Admission symptom severity, infarction of insula, and midbrain/pons were independent predictors of clinical outcome in acute ischemic stroke patients. The methodology of this hypothesis-generating study can help conceive quantitative population-based probabilistic models for prognostication or treatment triage in stroke patients, combining admission clinical and imaging findings-including infarct topography.


Asunto(s)
Isquemia Encefálica/diagnóstico , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Técnicas de Apoyo para la Decisión , Imagen de Difusión por Resonancia Magnética , Evaluación de la Discapacidad , Admisión del Paciente , Accidente Cerebrovascular/diagnóstico , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Isquemia Encefálica/mortalidad , Isquemia Encefálica/fisiopatología , Isquemia Encefálica/terapia , Bases de Datos Factuales , Femenino , Humanos , Modelos Logísticos , Masculino , Mesencéfalo/diagnóstico por imagen , Mesencéfalo/fisiopatología , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Puente/diagnóstico por imagen , Puente/fisiopatología , Valor Predictivo de las Pruebas , Prueba de Estudio Conceptual , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/terapia , Factores de Tiempo , Resultado del Tratamiento
8.
Neuroradiology ; 59(4): 419-421, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28303374

RESUMEN

PURPOSE: Minnelide is an experimental antineoplastic agent that is currently the subject of a phase 1 clinical trial for the treatment of pancreatic and gastrointestinal malignancies. In this study, we documented two cases of reversible acute cerebellar toxicity (REACT) associated with Minnelide and compared its radiological manifestations with other cerebellotoxic agents. METHODS: Both patients had histories of progressive metastatic cancer and participated in a phase 1 clinical trial with Minnelide. They had an MRI examination including T2WI, FLAIR and SWI, axial and coronal DWI, and ADC map on admission and follow up. RESULTS: In each patient, the initial MRI demonstrated increased signal on FLAIR and restricted diffusion in the cerebellar cortex without involvement of deep cerebellar nuclei or supratentorial areas. The presenting symptoms and the majority of imaging findings resolved on follow up MRI. CONCLUSION: To our knowledge, Minnelide has shown an uncommon radiologic pattern of isolated cerebellar cortical involvement compared to other causes of cerebellar toxicity. Since this is a new medication, physicians' familiarity with the presenting symptoms and its temporal association with the imaging findings is important.


Asunto(s)
Cerebelo/efectos de los fármacos , Cerebelo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Organofosfatos/toxicidad , Fenantrenos/toxicidad , Ensayos Clínicos Fase I como Asunto , Neoplasias del Colon/tratamiento farmacológico , Diterpenos , Compuestos Epoxi , Resultado Fatal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/tratamiento farmacológico
9.
Acta Radiol ; 58(7): 876-882, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27799573

RESUMEN

Background Recent studies have suggested a correlation between susceptibility-diffusion mismatch and perfusion-diffusion mismatch in acute ischemic stroke patients. Purpose To determine the clinical and imaging associations of susceptibility-diffusion mismatch in patients with acute ischemic stroke in the middle cerebral artery (MCA) territory. Material and Methods Consecutive patients with MCA territory acute ischemic stroke, who had magnetic resonance imaging (MRI) performed with susceptibility-weighted imaging (SWI) and diffusion-weighted imaging (DWI) within 24 h of symptom onset or time last-seen-well, were included. Two neuroradiologists reviewed SWI scans for SWI-DWI mismatch defined by regionally increased vessel number or diameter on SWI extending beyond the DWI hyperintensity territory in the affected hemisphere. The stroke severity at admission was evaluated using the National Institutes of Health Stroke Scale (NIHSS) score. Poor clinical outcome was defined by a 3-month modified Rankin Scale (mRS) score >2. Results The SWI-DWI mismatch was identified in 44 (29.3%) of 150 patients included in this study. Patients with SWI-DWI mismatch had smaller admission infarct volumes (31.2 ± 44.7 versus 55.9 ± 117.7 mL, P = 0.045) and were younger (60.4 ± 18.9 versus 67.1 ± 15.5, P = 0.026). After correction for age, admission NIHSS score, and infarct volume, the SWI-DWI mismatch was associated with a 22.6% lower rate of poor clinical outcome using propensity score matching ( P = 0.032). In our cohort, thrombolytic therapy showed no significant effect on outcome. Conclusion The presence of SWI-DWI mismatch in acute MCA territory ischemic infarct is associated with smaller infarct volume. Moreover, SWI-DWI mismatch was associated with better outcome after correction for infarct size, severity of admission symptoms, and age.


Asunto(s)
Isquemia Encefálica/diagnóstico , Imagen de Difusión por Resonancia Magnética , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Enfermedad Aguda , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
AJR Am J Roentgenol ; 207(4): 852-858, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27440521

RESUMEN

OBJECTIVE: Prior studies have shown that skull fractures overlying the dural venous sinuses predispose the patient to an increased risk of dural venous sinus thrombosis (DVST). However, extrinsic compression may also cause sinus compromise and simulate thrombosis. This study set out to evaluate the prevalence and discernibility of DVST versus direct sinus compression in the setting of an overlying skull fracture. MATERIALS AND METHODS: All initial head MDCT venography examinations performed at a level 1 trauma center over an 8-year period were reviewed (n = 347 patients). The examinations that showed an acute fracture overlying a dural sinus were included for review (n = 107 patients). Three neuroradiologists classified the MDCT venography findings as category 0 (normal), 1 (solely sinus compression), 2 (solely intraluminal thrombus), 3 (mixed sinus compression and DVST), or 4 (indeterminate). Clinical outcomes were assessed at 30-45 days after hospital discharge. RESULTS: The percentage of patients in each category was as follows: category 0 (31-33% patients), 1 (38-46%), 2 (5-9%), 3 (8-11%), and 4 (8-13%). Categories 2-4 were more likely in the transverse sinus-sigmoid sinus complex (22-30%) and multiple dural sinuses (47-53%) than in the superior sagittal sinus (SSS) (5%). Interobserver reliability was strong (κ = 0.627-0.772; p < 0.0001). Sinus category was associated with fracture site (p = 0.014) but not with clinical outcome (p = 0.236). CONCLUSION: Sinus compromise is common in patients with overlying skull fractures. Sinus compression can be distinguished from DVST on MDCT venography and is likely more prevalent than previously estimated. The fracture site may in part determine the pattern of compromise because fractures involving the transverse sinus-sigmoid sinus complex or multiple dural sinuses seem more likely to be affected by thrombosis than fractures involving the SSS.

11.
J Stroke Cerebrovasc Dis ; 25(10): 2464-9, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27373730

RESUMEN

BACKGROUNDS: This study aimed to investigate the possible asymmetric distribution of acute ischemic infarct lesions between patients with right-sided stroke versus left-sided stroke. METHODS: Acute ischemic stroke patients with unilateral infarct who underwent magnetic resonance imaging scan within 24 hours of onset were included. Infarct lesions were segmented on diffusion-weighted-imaging series and coregistered on the MNI-152 brain map. After flipping all lesions to the left side, voxel-based analysis was performed to evaluate for asymmetric distribution of infarct lesions using the stroke side as an independent variable. Symptom severity at admission was evaluated using the National Institutes of Health Stroke Scale score, and early clinical outcome with the modified Rankin Scale score at discharge. RESULTS: Of the 218 patients included in this study, 110 had right-sided ischemic infarcts whereas 108 had left-sided ischemic infarcts. There was no significant difference between patients with right-sided stroke versus left-sided stroke in terms of admission symptom severity, rate of treatment, stroke risk factors, and early clinical outcome. However, voxel-based analysis showed that ischemic infarcts of insular ribbon and lentiform nucleus were asymmetrically more common on the left-sided stroke compared to the right-sided stroke. The admission symptoms were more severe among patients with left insular ribbon and lentiform nucleus infarct compared to those with infarction of mirrored right anatomical regions (P = .019). CONCLUSIONS: Acute ischemic infarcts of the left insular ribbon and lentiform nucleus are asymmetrically more common compared to mirrored counterpart regions, presumably due to more severe symptoms at presentation. Otherwise, distribution of symptomatic infarcts to the rest of the brain is roughly symmetric.


Asunto(s)
Infarto Cerebral/diagnóstico por imagen , Cerebro/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Anciano , Anciano de 80 o más Años , Infarto Cerebral/fisiopatología , Infarto Cerebral/terapia , Cerebro/fisiopatología , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/fisiopatología , Evaluación de la Discapacidad , Femenino , Lateralidad Funcional , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
12.
Epilepsy Behav ; 48: 70-4, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26071927

RESUMEN

RATIONALE: Seizures are among the most common clinical presentations of posterior reversible encephalopathy syndrome (PRES). This syndrome has rarely been reported to cause chronic epilepsy or persistent cortical dysfunction. The prognostic value of EEG findings during PRES is unknown. We retrospectively evaluated EEG characteristics in patients with PRES in a single medical center. We also evaluated the long-term outcome regarding seizure occurrence beyond the acute phase in these patients. METHODS: We searched a radiology database at the University of Minnesota from 1997 to 2012 to identify patients with clinically and radiologically diagnosed PRES. Among the patients with PRES, we reviewed MRI images, EEG findings, clinical manifestations including seizure occurrences, and clinical outcomes beyond the acute phase. RESULTS: Seventy-five patients were included in the study. Fifty-eight out of seventy-five (77.3%) patients with PRES had seizures. A total of 48 EEG studies were performed in 38 patients. Generalized slowing was the most common EEG pattern. Among the 38 patients who had EEGs, 37 (97.3%) patients had diffuse or focal slowing of the background, and 11 (28.9%) patients had IEDs. Four out of seventy-five (5.3%) patients had seizures later than one month beyond their hospitalization for PRES. None of these 4 patients had seizures before the episode of PRES. Two patients developed chronic epilepsy, with seizures occurring later than one year after the PRES. CONCLUSION: Most patients who had seizures or who had epileptiform activities in EEG during PRES did not subsequently develop chronic epilepsy. No patient developed chronic epilepsy in the absence of clinical seizures during PRES. Posterior reversible encephalopathy syndrome may infrequently be associated with subsequent development of symptomatic epilepsy.


Asunto(s)
Encefalopatías/complicaciones , Encefalopatías/patología , Ondas Encefálicas/fisiología , Imagen por Resonancia Magnética/métodos , Lóbulo Parietal/patología , Convulsiones/etiología , Adulto , Anciano , Electroencefalografía , Epilepsia/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Lóbulo Occipital/patología , Síndrome de Leucoencefalopatía Posterior , Pronóstico , Estudios Retrospectivos , Convulsiones/diagnóstico
13.
Neuroradiology ; 57(11): 1103-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26242361

RESUMEN

INTRODUCTION: Stroke-like migraine attacks after radiation therapy (SMART) syndrome has a characteristic clinical presentation and postcontrast T1WI MRI appearance. Susceptibility-weighted imaging (SWI) may help distinguish SMART from other disorders that may have a similar postcontrast MRI appearance. METHODS: The MRI examinations of four patients with SMART syndrome are described herein, each of which included SWI, FLAIR, DWI, and postcontrast T1WI on the presenting and follow-up MRI examinations. RESULTS: In each, the initial SWI MRI demonstrated numerous susceptibility hypointensities <5 mm in size throughout the cerebrum, particularly within the periventricular white matter (PVWM), presumably related to radiation-induced cavernous hemangiomas (RICHs). By follow-up MRI, each postcontrast examination had demonstrated resolution of the gyriform enhancement on T1WI, without susceptibility hypointensities on SWI within those previously enhancing regions. CONCLUSION: These preliminary findings suggest that SWI may help identify SMART syndrome or at least help discriminate it from other disorders, by the findings of numerous susceptibility hypointensities on SWI likely representing RICHs, gyriform enhancement on T1WI, and postsurgical findings or appropriate clinical history.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Trastornos Migrañosos/etiología , Trastornos Migrañosos/patología , Traumatismos por Radiación/complicaciones , Traumatismos por Radiación/patología , Radioterapia/efectos adversos , Adulto , Anciano , Encéfalo/patología , Encéfalo/efectos de la radiación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/patología , Síndrome
14.
J Neuroophthalmol ; 34(3): 218-22, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24213568

RESUMEN

BACKGROUND: Prone is the preferred patient position for fluoroscopic-guided lumbar puncture (LP). Normative data for cerebrospinal fluid (CSF) opening pressure (OP) exist for lateral decubitus (LD) positioning only and have not been defined for the prone position. This study compares CSF OP values in the prone and LD positions and examines the effect of body mass index (BMI) on OP. METHODS: Patients undergoing diagnostic or therapeutic fluoroscopic-guided LP were recruited prospectively at 2 tertiary care centers from 2009 to 2012. Following prone fluoroscopic-guided LP, patients were rolled to the LD position for repeat CSF OP measurement. In addition to comparing the mean OP in each position, the relationships between OP, body position, and BMI were also explored. RESULTS: Fifty-two patients were enrolled. A mean OP difference of 1.2 cm H2O was observed (prone: 26.5 cm H2O; LD: 27.7 cm H2O; P = 0.07). No correlation between CSF OP and BMI was seen in either position. CONCLUSIONS: No statistically or clinically significant difference between prone and LD OP was identified. BMI does not appear to affect CSF OP measurement in either position.


Asunto(s)
Presión del Líquido Cefalorraquídeo , Papiledema/diagnóstico , Posicionamiento del Paciente , Postura , Seudotumor Cerebral/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Diazepam/administración & dosificación , Femenino , Fluoroscopía , Humanos , Hipnóticos y Sedantes/administración & dosificación , Masculino , Persona de Mediana Edad , Posición Prona , Punción Espinal , Adulto Joven
15.
Heliyon ; 10(10): e30106, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38799748

RESUMEN

Objective: Natural language processing (NLP) can generate diagnoses codes from imaging reports. Meanwhile, the International Classification of Diseases (ICD-10) codes are the United States' standard for billing/coding, which enable tracking disease burden and outcomes. This cross-sectional study aimed to test feasibility of an NLP algorithm's performance and comparison to radiologists' and physicians' manual coding. Methods: Three neuroradiologists and one non-radiologist physician reviewers manually coded a randomly-selected pool of 200 craniospinal CT and MRI reports from a pool of >10,000. The NLP algorithm (Radnosis, VEEV, Inc., Minneapolis, MN) subdivided each report's Impression into "phrases", with multiple ICD-10 matches for each phrase. Only viewing the Impression, the physician reviewers selected the single best ICD-10 code for each phrase. Codes selected by the physicians and algorithm were compared for agreement. Results: The algorithm extracted the reports' Impressions into 645 phrases, each having ranked ICD-10 matches. Regarding the reviewers' selected codes, pairwise agreement was unreliable (Krippendorff α = 0.39-0.63). Using unanimous reviewer agreement as "ground truth", the algorithm's sensitivity/specificity/F2 for top 5 codes was 0.88/0.80/0.83, and for the single best code was 0.67/0.82/0.67. The engine tabulated "pertinent negatives" as negative codes for stated findings (e.g. "no intracranial hemorrhage"). The engine's matching was more specific for shorter than full-length ICD-10 codes (p = 0.00582x10-3). Conclusions: Manual coding by physician reviewers has significant variability and is time-consuming, while the NLP algorithm's top 5 diagnosis codes are relatively accurate. This preliminary work demonstrates the feasibility and potential for generating codes with reliability and consistency. Future works may include correlating diagnosis codes with clinical encounter codes to evaluate imaging's impact on, and relevance to care.

16.
PET Clin ; 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39482219

RESUMEN

MR imaging is currently the main imaging modality used for the diagnosis and post therapeutic assessment of glioblastomas. Recently, several innovative PET radioactive tracers have been investigated for the evaluation of glioblastomas (GBM). These radiotracers target several biochemical and pathophysiological processes seen in tumors. These include glucose metabolism, DNA synthesis and cell proliferation, amino acid transport, cell membrane biosynthesis, specific membrane antigens such as prostatic specific membrane antigens, fibroblast activation protein inhibitor, translocator protein and hypoxia sensing agents, and antibodies targeting specific cell receptor antigen. This review aims to discuss the clinical value of these PET radiopharmaceuticals in the evaluation and treatment of GBMs.

17.
AJR Am J Roentgenol ; 201(3): 631-8, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23971457

RESUMEN

OBJECTIVE: Although posterior reversible encephalopathy syndrome (PRES) typically involves cortical or subcortical edema of the cerebrum, only individual cases have been described of a variant involving the central brainstem and basal ganglia and lacking cortical and subcortical edema. We evaluated FLAIR and T2-weighted images of 124 patients with confirmed PRES to determine the incidence of this uncommon variant, which we refer to as the "central variant"; to determine which structures are involved in this variant; and to determine the associated causes. CONCLUSION: We found that five of the 124 patients (4%) with PRES had MR findings consistent with the central variant-that is, either brainstem or basal ganglia involvement and a lack of cortical or subcortical edema of the cerebrum. The thalami were involved in all five PRES patients with MR findings consistent with the central variant, but there was variable involvement of the posterior limb of the internal capsule (4/5), cerebellum (3/5), and periventricular white matter (3/5); in each patient, there was improvement both clinically and on MRI. The causes of PRES in these five patients were hypertension (n=2), cyclosporine (n=2), and eclampsia (n=1). The incidence of the central variant may be increasing because of an improving awareness of the diverse imaging patterns of PRES.


Asunto(s)
Ganglios Basales/patología , Tronco Encefálico/patología , Imagen por Resonancia Magnética/métodos , Síndrome de Leucoencefalopatía Posterior/patología , Adulto , Edema Encefálico/patología , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
18.
Acta Radiol ; 54(4): 455-61, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23386735

RESUMEN

BACKGROUND: Contrast-enhanced, fat-suppressed T1-weighted imaging (CET1WI) magnetic resonance imaging (MRI) is quite sensitive in detecting acute optic neuritis (ON), but ON remains a clinical diagnosis. MRI is indicated to evaluate demyelinating brain lesions rather than the optic nerves, while "routine" brain protocols typically include axial FLAIR and DWI. PURPOSE: To evaluate the accuracy of axial, fat-suppressed FLAIR and DWI sequences used for our routine brain imaging in detecting acute ON, as compared to CET1WI and the clinical diagnosis. MATERIAL AND METHODS: The clinical data and MRI examinations were retrospectively reviewed of 60 patients presenting to a neuro-ophthalmologist for various visual symptoms. Each patient underwent dedicated neuro-ophthalmologic examination, with axial 5 mm fat-suppressed FLAIR and DWI (part of "routine" brain MRI protocol), as well as 3 mm axial and coronal fat-suppressed CET1WI (part of dedicated orbit MRI protocol). Two neuroradiologists independently evaluated FLAIR and DWI, while CET1WI was reviewed by consensus. RESULTS: Thirty-one patients were clinically positive, 29 negative for ON (total = 34 positive and 86 negative nerves). The sensitivities of FLAIR, DWI, and CET1WI for ON were 75.7-77.3%, 77.3%, and 89.5%, respectively; the specificities were 90.5-93.5%, 80.4-82.7%, and 86.0%, respectively; the accuracies were 85.7-88.2%, 79.5-81.1%, and 87.0%, respectively. Inter-observer kappa was 0.783 for FLAIR, and 0.605 for DWI; intra-observer kappa was 0.746-0.816 for FLAIR, and 0.674-0.699 for DWI (each P < 0.0001). CONCLUSION: Being more specific, but not as sensitive, as dedicated CET1WI in acute ON, axial fat-suppressed FLAIR likely has additional value in evaluating for acute ON in "routine" brain MR protocols evaluating for demyelinating disease, while DWI may be hampered by artifacts.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neuritis Óptica/diagnóstico , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Imagen de Difusión por Resonancia Magnética , Femenino , Gadolinio DTPA , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad
19.
J Alzheimers Dis ; 91(4): 1313-1322, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36617780

RESUMEN

BACKGROUND: Lower cerebral blood flow (CBF) and excessive brain atrophy are linked to Alzheimer's disease (AD). It is still undetermined whether reduced CBF precedes or follows brain tissue loss. OBJECTIVE: We compared total CBF (tCBF), global cerebral perfusion (GCP), and volumes of AD-prone regions between cognitively normal (CN) and early amnestic mild cognitive impairment (aMCI) and tested their associations with cognitive performance to assess their predictive value for differentiation between CN and early aMCI. METHODS: A total of 74 participants (mean age 69.9±6.2 years, 47 females) were classified into two groups: 50 CN and 24 aMCI, of whom 88% were early aMCI. tCBF, GCP, and global and regional brain volumetry were measured using phase-contrast and T1-weighted MRI. Neuropsychological tests tapping global cognition and four cognitive domains (memory, executive function, language, and visuospatial) were administered. Comparisons and associations were investigated using analyses of covariance (ANCOVA) and linear regression analyses, respectively. RESULTS: Women had significantly higher GCP than men. Both, tCBF and GCP were significantly reduced in aMCI compared with CN, while differences in volumes of cerebral gray matter, white matter, and AD-prone regions were not significant. tCBF and GCP were significantly associated with global cognition (standardized beta (stß) = 0.324 and stß= 0.326) and with memory scores (stß≥0.297 and stß≥0.264) across all participants. Associations of tCBF and GCP with memory scores were also significant in CN (stß= 0.327 and stß= 0.284) and in aMCI (stß= 0.627 and stß= 0.485). CONCLUSION: Reduced tCBF and GCP are sensitive biomarkers of early aMCI that likely precede brain tissue loss.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Sustancia Blanca , Masculino , Humanos , Femenino , Anciano , Encéfalo , Cognición , Pruebas Neuropsicológicas , Circulación Cerebrovascular/fisiología , Imagen por Resonancia Magnética
20.
J Clin Neurosci ; 95: 38-43, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34929649

RESUMEN

Posterior reversible encephalopathy syndrome (PRES) is a neurological disorder characterized by headache, seizures, confusion and visual disturbances, as well as potentially reversible neuroimaging findings in most patients after proper treatment. Seizures is one of the most common clinical presentations of PRES. This review summarizes the potential pathophysiology and clinical features of PRES, as well as a multimodal approach to imaging and also briefly discusses the phenomenon of seizures in paediatric population.


Asunto(s)
Síndrome de Leucoencefalopatía Posterior , Niño , Cefalea , Humanos , Imagen por Resonancia Magnética , Neuroimagen , Síndrome de Leucoencefalopatía Posterior/diagnóstico por imagen , Convulsiones/diagnóstico por imagen , Convulsiones/etiología
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