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1.
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.

2.
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
3.
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
5.
Clin Neurol Neurosurg ; 221: 107403, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35933966

RESUMEN

BACKGROUND: Neurovascular compression (NVC) has been the primary hypothesis for the underlying mechanism of classical trigeminal neuralgia (TN). However, a substantial body of literature has emerged highlighting notable exceptions to this hypothesis. The purpose of this study is to assess the reliability and diagnostic accuracy of high resolution, high contrast MRI-determined neurovascular contact for TN. METHODS: We performed a retrospective, randomized, and blinded parallel characterization of neurovascular interaction and diagnosis in a population of TN patients and controls using four expert reviewers. Performance statistics were calculated, as well as assessments for generalizability using shuffled bootstraps. RESULTS: Fair to moderate agreement (ICC: 0.32-0.68) about diagnosis between reviewers was observed using MRIs from 47 TN patients and 47 controls. On average reviewers performed no better than chance when diagnosing participants, with an accuracy of 0.57 (95% CI 0.40, 0.59) per patient. CONCLUSION: While MRI is useful in determining structural causes in secondary TN, expert reviewers do no better to only slightly better than chance with distinguishing TN with MRI, despite moderate agreement. Further, the causal role of NVC for TN is not clear, limiting the applicability of MRI to diagnose or prognosticate treatment of TN.


Asunto(s)
Neuralgia del Trigémino , Humanos , Imagen por Resonancia Magnética/métodos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Nervio Trigémino/patología , Neuralgia del Trigémino/etiología
6.
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
7.
Clin Neuroradiol ; 31(3): 611-617, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32757073

RESUMEN

PURPOSE: This study was carried out to evaluate the utility of susceptibility-weighted imaging (SWI) in demonstrating retinal hemorrhages (RH) in pediatric head trauma. METHODS: Over a period of 7 years 67 children (age 0-4 years) with head trauma and MRI were included as either abusive head trauma (AHT) (n = 23), non-abusive head trauma (NAHT) (n = 38), or indeterminate (n = 6). Two pediatric neuroradiologists jointly reviewed the MR images for the presence of RH and sensitivity and specificity of SWI and T2WI were calculated. RESULTS: The dilated fundoscopic examination (DFE) was positive for RH in 18/23 (78.3%) of the AHT group, 5/38 (13.2%) in the NAHT group, and 4/6 (66.7%) in the indeterminate group. Regarding the SWI MRI findings, SWI was positive for RH in 13/23 (%56.5), while T2WI was positive in 6/23 (%26.1) of the AHT group. Based on utilizing DFE as a standard, the sensitivity and specificity of SWI in the detection of RH was 63% and 100%, respectively and 30% and 100%, respectively on T2WI. CONCLUSION: Our results suggest that SWI is a useful diagnostic tool for detection of RH in pediatric head trauma in whom DFE is difficult to perform.


Asunto(s)
Maltrato a los Niños , Traumatismos Craneocerebrales , Niño , Maltrato a los Niños/diagnóstico , Preescolar , Traumatismos Craneocerebrales/complicaciones , Traumatismos Craneocerebrales/diagnóstico por imagen , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Hemorragia Retiniana/diagnóstico por imagen , Sensibilidad y Especificidad
8.
J Neuroimaging ; 31(1): 144-150, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32920938

RESUMEN

BACKGROUND AND PURPOSE: This study aimed to assess characteristic regions of MRI involvement utilizing diffusion weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) at urea cycle disorder (UCD) diagnosis to determine the possible association between initial MRI patterns within 10 days of the first hyperammonemia episode, serum ammonia levels, and severity of neurological outcome based on clinical follow-up of >30 days. METHODS: Ten patients with UCDs (4 females; median age: 5.4 years, age range: 6 days-54 years) were included who underwent MRI during a first episode of hyperammonemia. The topographical distribution of the DWI and FLAIR abnormalities in the cerebral cortex, deep gray matter, white matter, posterior limb of internal capsule, cerebral peduncle, and cerebellum was evaluated. Possible correlations between the brain injury patterns on DWI/FLAIR images, serum ammonia levels, and severity of neurological outcome were investigated by a trend correlation. RESULTS: The UCD cohort (n = 10) involved four ornithine transcarbamoylase deficiencies, four argininosuccinic aciduria, one carbomoylphosphate synthetase deficiency, and one citrullinemia type-1. The observed trend in the distribution of DWI abnormalities as the severity of neurological sequela outcome increased was with diffuse cerebral cortex or corpus striatum involvement. Patients with initial peak serum ammonia ≥450 µmol/L had a grade 2 to 4 outcome, and those with peak ammonia <450 µmol/L had a grade 0 or 1 outcome. CONCLUSIONS: The presence of more severe neurological outcome could be associated with diffuse cerebral cortex or corpus striatum involvement on DWI and high serum ammonia levels in patients with UCD.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Neuroimagen , Trastornos Innatos del Ciclo de la Urea/diagnóstico por imagen , Adulto , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trastornos Innatos del Ciclo de la Urea/complicaciones , Adulto Joven
9.
J Neuroimaging ; 30(6): 930-935, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32770607

RESUMEN

BACKGROUND AND PURPOSE: Children receiving chemotherapy, or immunosuppression have an increased risk for pediatric posterior reversible encephalopathy syndrome (pPRES); pPRES is scantly described in cerebral X-linked adrenoleukodystrophy (cALD) patients, for which hematopoietic stem cell transplantation improves outcomes. This study aimed to describe distinctive lesion patterns, distribution, and evolution of neuroimaging findings in PRES in a single-center pediatric cohort of cALD. METHODS: We retrospectively identified all clinically acquired brain MRIs of children with cALD at a tertiary care university hospital between 1995 and 2020. We reviewed clinical features, conventional MRI, and diffusion-weighted imaging findings of patients with gray matter and white matter (WM) changes suggestive of concurrent PRES-cALD. Associations between the distinctive anatomic features, distribution, and abnormal signal intensity on MRI were examined with regard to the etiology and clinical outcome. RESULTS: Our search revealed a series of eight pediatric cALD patients presenting with seizures, headache, or altered mental status with MRI findings suggestive of both PRES and cALD simultaneously. In each, the cortical-subcortical vasogenic edema on fluid-attenuated inversion recovery was consistent with pPRES, overlying the periventricular WM (PVWM) involvement typical of cALD. Of these 8 patients, the cortical-subcortical lesions on FLAIR were completely reversible on follow-up MRI in 7, but only partially reversible in 1. CONCLUSIONS: It is crucial to recognize that pPRES can occur in cALD, notably, the cortical edema and leptomeningeal enhancement can accelerate the diagnosis of superimposed pPRES, while the PVWM lesions of cALD remain following the resolution of pPRES.


Asunto(s)
Adrenoleucodistrofia/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Síndrome de Leucoencefalopatía Posterior/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Adolescente , Adrenoleucodistrofia/complicaciones , Adrenoleucodistrofia/patología , Niño , Preescolar , Femenino , Sustancia Gris/patología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Neuroimagen , Síndrome de Leucoencefalopatía Posterior/complicaciones , Síndrome de Leucoencefalopatía Posterior/patología , Estudios Retrospectivos , Sustancia Blanca/patología
10.
Clin Imaging ; 67: 194-197, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32862127

RESUMEN

We report an unusual case of radiation-induced glioma with a very long latent period. The patient had a history of brain stem glioma diagnosed 40 years earlier treated by radiotherapy. For treatment of radiation-induced glioma, radiotherapy was utilized again. Following therapy, the patient presented with an acute pontine infarct. To the best of our knowledge this may be the first report of radiation-induced glioma and radiation-induced stroke occurring within the same patient.


Asunto(s)
Neoplasias del Tronco Encefálico/diagnóstico por imagen , Glioma/diagnóstico por imagen , Neoplasias Encefálicas , Neoplasias del Tronco Encefálico/etiología , Neoplasias del Tronco Encefálico/radioterapia , Glioma/etiología , Glioma/radioterapia , Humanos , Infarto/complicaciones , Radioterapia/efectos adversos
11.
J Neuroimaging ; 30(3): 335-341, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32324333

RESUMEN

BACKGROUND AND PURPOSE: Comprehensive imaging characterization of the morphology and luminal patency of cerebral aneurysms are cornerstones of their successful treatment and subsequent appropriate management. Giant cerebral aneurysms (GCAs), a distinct subgroup of aneurysms, are defined by large size (≥ 25 mm in greatest diameter), complex blood flow dynamics, and a high risk of rupture. The purpose of this study is to explore compare multiple imaging modalities in the assessment of GCAs. METHODS: This study retrospectively evaluated CT angiography (CTA), 3D time-of-flight (TOF) MR angiography (MRA), contrast-enhanced MRA (CEMRA), and digital subtraction angiography (DSA) in characterizing GCAs in 21 patients. RESULTS: Aneurysm size ranged from 26 to 58 mm (mean 31.3 ± 12.2) and 18/21 (85.7%) had intraluminal thrombus. No significant difference was found between the aneurysmal sizes of any two modalities regarding comparisons of CTA, 3D TOFMRA, and CEMRA. However, there were significant differences in the aneurysmal patency visibility grade between CTA versus TOFMRA and CTA versus CEMRA. Moreover, the patent luminal size measured on CTA was significantly larger than DSA. CONCLUSIONS: CTA, 3D TOFMRA, and CEMRA are equivalent in the delineation of size of GCAs. Nevertheless, 3D TOFMRA and CEMRA seem to be inferior to CTA in demonstrating luminal size/patency, likely because of the signal loss resulting from the presence of intraluminal thrombus and flow turbulence. Moreover, CTA is superior to DSA in determining lumen patency in GCAs, probably due to CTA's multipass-related luminal enhancement while DSA general fills the lesion via the first pass of enhancement or soon thereafter. In addition, CTA may also better demonstrate intraluminal thrombus, adjacent anatomical structures, and calcified rims.


Asunto(s)
Angiografía de Substracción Digital/métodos , Encéfalo/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Angiografía por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Angiografía Cerebral/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
12.
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
13.
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
14.
Neuroimage Clin ; 24: 101981, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31473544

RESUMEN

OBJECTIVE: The supply territories of main cerebral arteries are predominantly identified based on distribution of infarct lesions in patients with large arterial occlusion; whereas, there is no consensus atlas regarding the supply territories of smaller end-arteries. In this study, we applied a data-driven approach to construct a stroke atlas of the brain using hierarchical density clustering in large number of infarct lesions, assuming that voxels/regions supplied by a common end-artery tend to infarct together. METHODS: A total of 793 infarct lesions on MRI scans of 458 patients were segmented and coregistered to MNI-152 standard brain space. Applying a voxel-wise data-driven hierarchical density clustering algorithm, we identified those voxels that were most likely to be part of same infarct lesions in our dataset. A step-wise clustering scheme was applied, where the clustering threshold was gradually decreased to form the first 20 mother (>50 cm3) or main (1-50 cm3) clusters in addition to any possible number of tiny clusters (<1 cm3); and then, any resultant mother clusters were iteratively subdivided using the same scheme. Also, in a randomly selected 2/3 subset of our cohort, a bootstrapping cluster analysis with 100 permutations was performed to assess the statistical robustness of proposed clusters. RESULTS: Approximately 91% of the MNI-152 brain mask was covered by 793 infarct lesions across patients. The covered area of brain was parcellated into 4 mother, 16 main, and 123 tiny clusters at the first hierarchy level. Upon iterative clustering subdivision of mother clusters, the brain tissue was eventually parcellated into 1 mother cluster (62.6 cm3), 181 main clusters (total volume 1107.3 cm3), and 917 tiny clusters (total volume of 264.8 cm3). In bootstrap analysis, only 0.12% of voxels, were labelled as "unstable" - with a greater reachability distance in cluster scheme compared to their corresponding mean bootstrapped reachability distance. On visual assessment, the mother/main clusters were formed along supply territories of main cerebral arteries at initial hierarchical levels, and then tiny clusters emerged in deep white matter and gray matter nuclei prone to small vessel ischemic infarcts. CONCLUSIONS: Applying voxel-wise data-driven hierarchical density clustering on a large number of infarct lesions, we have parcellated the brain tissue into clusters of voxels that tend to be part of same infarct lesion, and presumably representing end-arterial supply territories. This hierarchical stroke atlas of the brain is shared publicly, and can potentially be applied for future infarct location-outcome analysis.


Asunto(s)
Atlas como Asunto , Infarto Encefálico/diagnóstico por imagen , Infarto Encefálico/patología , Imagen por Resonancia Magnética , Neuroimagen , Humanos
15.
Eur J Radiol Open ; 6: 243-257, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31309133

RESUMEN

PURPOSE: To describe non-metabolic, non-infectious etiologies of acute toxic leukoencephalopathy (ATL) on DWI MRI, and provide a useful acronym to remember them. MATERIAL AND METHODS: Our PACS archive was reviewed, yielding 185 patients with suspected ATL per MRI reports and clinical follow up; infectious or metabolic causes were excluded. RESULT/DISCUSSION: The 87 included non-infectious, non-metabolic ATL patients' etiologies are represented by the acronym 'CHOICES': chemotherapy ('C',n = 34); heroin-induced ('H',n = 6), opioid analogues ('O',n = 14); immunosuppressant ('I',n = 11) or imidazole (n = 2); cocaine ('C',n = 1); environmental or ethanol abuse ('E',n = 5), splenial lesions ('S',n = 9), and 'other' (n = 5). CONCLUSION: The "CHOICES" acronym delineates various toxic etiologies of ATL.

16.
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
17.
Clin Neuroradiol ; 29(3): 505-513, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29663010

RESUMEN

PURPOSE: Septo-optic dysplasia is a congenital disorder consisting of optic nerve hypoplasia and absent septum pellucidum. While associated anomalies have been described, olfactory sulcus and bulb-tract hypoplasia have been scantily reported and was the focus of this study. METHODS: The picture archival and communications system and radiology information system (PACS-RIS) was searched over 15 years for patients with suspected septo-optic dysplasia (n = 41) and cerebral magnetic resonance imaging (MRI). Included patients had coronal (≤3 mm), axial (≤4 mm), and sagittal (≤4 mm) imaging reviewed by two staff neuroradiologists by consensus. Both olfactory sulcus and bulb-tract hypoplasia were ascribed a grade of 0 (normal) to 3 (complete hypoplasia). Other associated congenital anomalies were recorded, if present. Incidence of anomalies were compared to age-matched and gender-matched control patients. RESULTS: Out of 41 septo-optic dysplasia patients 33 were included (mean age = 120.7 months), with 8 excluded due to isolated septum pellucidum absence (n = 5), isolated bilateral optic hypoplasia (n = 2), or inadequate imaging (n = 1). An olfactory sulcus was hypoplastic on one or both sides in 14/33 (42.4%). Olfactory bulb hypoplasia was noted in one or both tracts in 15/33 (45.4%). A significant correlation was found between degree of olfactory sulcal and bulb-tract hypoplasia (ρ = 0.528, p = 0.0009). Other anomalies were: anterior falx dysplasia (n = 16, 48.5%), incomplete hippocampal inversion (n = 14, 42.4%), polymicrogyria (n = 11, 33.3%), callosal complete or partial agenesis (n = 10, 30.3%), schizencephaly (n = 8, 24.2%), ectopic posterior pituitary (n = 6, 18.2%), and nodular heterotopia (n = 4, 12.1%). Of the age-matched control patients 10/33 (30.3%) had at least mild anterior falx hypoplasia, and 1 control patient was noted to have unilateral incomplete hippocampal inversion (IHI); none of the age-matched control patients had olfactory sulcus or bulb-tract hypoplasia. CONCLUSION: Olfactory sulcus and bulb-tract hypoplasia are fairly common in septo-optic dysplasia and can be discordant between sides. Of the other associated anomalies, anterior falx dysplasia seems to be the most common.


Asunto(s)
Imagen por Resonancia Magnética , Bulbo Olfatorio/diagnóstico por imagen , Corteza Prefrontal/diagnóstico por imagen , Displasia Septo-Óptica/diagnóstico por imagen , Adolescente , Adulto , Agenesia del Cuerpo Calloso/diagnóstico por imagen , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Hipocampo/anomalías , Hipocampo/diagnóstico por imagen , Humanos , Lactante , Masculino , Persona de Mediana Edad , Bulbo Olfatorio/anomalías , Corteza Prefrontal/anomalías , Estudios Retrospectivos , Esquizencefalia/diagnóstico por imagen , Displasia Septo-Óptica/patología
18.
Clin Neuroradiol ; 29(2): 253-261, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29362831

RESUMEN

BACKGROUND AND PURPOSE: Differentiating Abusive Head Trauma (AHT) from Non-abusive Head trauma (NAHT) has profound clinical prognostic and legal implications, as certain imaging findings can individually be more suggestive of NAHT, while others are more suggestive of AHT. This study was set out to evaluate for an association between the various imaging findings in AHT with outcome. MATERIAL AND METHODS: Over 7-years, 55 children (age 0-4 years') with head trauma and magnetic resonance imaging (MRI) were included as either: abusive (n = 16), non-abusive (n = 35), or indeterminate (n = 4). Two pediatric neuroradiologists jointly reviewed the imaging. The frequency of imaging findings and their association with ≥6 months' outcome were calculated. RESULTS: Comparing abusive versus non-abusive head trauma, complex subdural hematoma was present in 81% (n = 13/16) and 29% (n = 10/35), hypoxic-ischemic injury in 44% (n = 7/16) and 6% (n = 2/35), and diffuse axonal injury in 12% (n = 2/16) and 26% (n = 9/35), respectively. Susceptibility-weighted imaging (SWI) retinal hemorrhages were absent in non-abusive trauma (0/35), but present in 44% (n = 7/16) of the abusive group. In abuse, simple subdural hematomas were absent. Significant associations were found between the presence of abusive trauma with both hypoxic ischemic insult (OR = 12.83, p = 0.0024) and complex subdural hematoma (OR = 10.83, p = 0.0007). The presence of hypoxic ischemic injury (HII) did correlate significantly with clinical outcome (p = 0.017), while retinal hemorrhages on SWI and complex subdural hematoma did not (p = 0.1696-p = 0.2496). CONCLUSION: Neuroimaging findings can be helpful in discriminating these two conditions on presentation, as well as in helping solidify the suspicion of AHT. Regarding eventual outcome in AHT, the most important predictor is clearly HII.


Asunto(s)
Maltrato a los Niños/diagnóstico , Traumatismos Craneocerebrales/etiología , Accidentes por Caídas/estadística & datos numéricos , Accidentes de Tránsito/estadística & datos numéricos , Lesiones Traumáticas del Encéfalo/etiología , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Hematoma Subdural/diagnóstico , Hematoma Subdural/etiología , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Pronóstico , Estudios Retrospectivos , Fracturas Craneales/diagnóstico , Fracturas Craneales/etiología , Tomografía Computarizada por Rayos X
19.
Eur J Radiol Open ; 5: 194-201, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30456218

RESUMEN

PURPOSE: Acute encephalopathic syndromes can present a diagnostic challenge due to the wide range of possible etiologies, which also can have vastly different outcomes. The presence of diffuse cortical injury (DCI) on diffusion-weighted imaging (DWI) can help narrow the differential diagnosis. The aim of this review is to categorize the range of possible etiologies of DCI into a useful acronym, "CRUMPLED". METHODS: A review of the PACS system was completed to find a characteristic example of patients with DCI on DWI from different etiologies. The diagnosis was confirmed for each example via a subsequent review of the electronic medical record used to assess for data such as biopsy results, laboratory values, and clinical correlation. The electronic exhibit intends to demonstrate several sample cases of each letter within the acronym, and to demonstrate which types of DCI are potentially reversible or irreversible. FINDINGS/DISCUSSION: The possible etiologies of DCI on DWI can be organized using the acronym "CRUMPLED": 'C' = Creutzfeldt-jakob disease, 'R' =  reversible cerebral vasoconstriction syndrome; 'U' = urea cycle disorders (hyperammonemia) and Uremia; 'M' = mitochondrial (cytopathy/encephalopathy); 'P' = prolonged seizure and posterior reversible encephalopathy (PRES); 'L' = laminar necrosis (hypoxic-ischemic encephalopathy) and liver disease (acute hepatic encephalopathy); 'E' = encephalitis (infectious meningoencephalitis); 'D' = diabetes mellitus (hypoglycemia). Other secondary imaging findings (outside of DWI) can be used to help differentiate between the aforementioned etiologies, such as the use of ADC maps, FLAIR imaging, intravenous contrast. CONCLUSION: "CRUMPLED" is proposed as a convenient acronym for the categorization of a diverse range of acute etiologies associated with DCI on DWI, arising from varying degrees of cytotoxic edema. These etiologies can range from being potentially reversible (e.g. hyperammonemia or prolonged seizures) to irreversible (e.g. hypoxic-ischemic injury).

20.
Eur J Radiol Open ; 5: 45-51, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29719858

RESUMEN

BACKGROUND: Neurotoxoplasmosis is a common opportunistic infection in HIV/AIDS patients. Imaging identification of neurotoxoplasmosis assists in timely treatment. PURPOSE: To delineate the frequency of imaging abnormalities in patients with neurotoxoplasmosis on different MR sequences with a particular focus on SWI, and NCCT. MATERIAL AND METHODS: The PACS database was retroactively searched over a 5-year period for patients with neurotoxoplasmosis who underwent MRI with SWI. Included patients had imaging features of neurotoxoplasmosis based on consensus review by two neuroradiologists, a clinical diagnosis of neurotoxoplasmosis at the time of MRI, and diagnostic confirmation based on positive serum or CSF serology or histopathology; 15 patients were included. The number of abnormal foci with restricted diffusion, increased FLAIR signal, intrinsic T1 hyperintensity, abnormal enhancement (CE-T1WI), and intrinsic hyperdensity on CT were recorded. RESULTS: Intralesional susceptibility signal (ISS) foci on SWI were observed in 93.3% of patients with neurotoxoplasmosis (mean size 5.2 ±â€¯3.8 mm). The average number of ISS foci was 3.9 per patient; 3/15 (20.0%) had a single ISS. Amongst other MR sequences, hyperintense FLAIR foci were the most common abnormalities observed (12.4 lesions/patient), followed by enhancing foci (8.2 lesions/patient), foci of restricted diffusion (7.1 lesions/patient), and intrinsic T1 hyperintense foci (3.4 lesions/patient). Abnormalities were least frequently observed on NCCT: abnormalities were identified in 5/15 (33.3%) patients, at a rate of 0.4 lesions/patient. CONCLUSION: ISS foci are present in the vast majority of neurotoxoplasmosis patients, likely representing hemorrhage. The incidence and frequency of other abnormal foci are highest on FLAIR, and lowest on NCCT.

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