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1.
Prenat Diagn ; 44(4): 499-510, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38013494

RESUMEN

OBJECTIVE: To evaluate the prenatal diagnosis of closed dysraphism (CD) and its correlation with postnatal findings and neonatal adverse outcomes. METHODS: A retrospective cohort study including pregnancies diagsnosed with fetal CD by prenatal ultrasound (US) and magnetic resonance imaging (MRI) at a single tertiary center between September 2011 and July 2021. RESULTS: CD was diagnosed prenatally and confirmed postnatally in 12 fetuses. The mean gestational age of prenatal imaging was 24.2 weeks, in 17% the head circumference was ≤fifth percentile and in 25% the cerebellar diameter was ≤fifth percentile. US findings included banana sign in 17%, and lemon sign in 33%. On MRI, posterior fossa anomalies were seen in 33% of cases, with hindbrain herniation below the foramen magnum in two cases. Mean clivus-supraocciput angle (CSA) was 74°. Additional anomalies outside the CNS were observed in 50%. Abnormal foot position was demonstrated prenatally in 17%. Neurogenic bladder was present in 90% of patients after birth. CONCLUSION: Arnold Chiari II malformation and impaired motor function can be present on prenatal imaging of fetuses with CD and may be associated with a specific type of CD. Prenatal distinction of CD can be challenging. Associated extra CNS anomalies are frequent and the rate of neurogenic urinary tract dysfunction is high.


Asunto(s)
Malformación de Arnold-Chiari , Malformaciones del Sistema Nervioso/diagnóstico , Disrafia Espinal , Embarazo , Femenino , Recién Nacido , Humanos , Lactante , Estudios Retrospectivos , Diagnóstico Prenatal/métodos , Imagen por Resonancia Magnética/métodos , Ultrasonografía Prenatal/métodos
2.
Semin Neurol ; 43(3): 439-453, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37562454

RESUMEN

Intracranial venous pathologies are a historically underrecognized group of disorders that can have a devastating impact on patients. Despite advancements in peripheral venous disorders and arterial neurointerventions, intracranial venous pathologies have received comparatively little attention. Understanding the anatomy, physiology, clinical relevance, and treatment options of intracranial venous pathologies is fundamental to evolving therapies and research priorities. This article provides an overview of major intracranial venous pathologies, the respective pathophysiologies, and treatment options.

3.
Pediatr Blood Cancer ; 70 Suppl 4: e30165, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36565281

RESUMEN

A standardized imaging protocol for pediatric oncology patients is essential for accurate and efficient imaging, while simultaneously promoting collaborative understanding of pathologies and radiologic assessment of treatment response. The objective of this article is to provide standardized pediatric imaging guidelines and parameters for evaluation of tumors of the pediatric orbit, calvarium, skull base, and temporal bone. This article was drafted based on current scientific literature as well as consensus opinions of imaging experts in collaboration with the Children's Oncology Group Diagnostic Imaging Committee, Society of Pediatric Radiology Oncology Committee, and American Society of Pediatric Neuroradiology.


Asunto(s)
Neoplasias de la Base del Cráneo , Humanos , Niño , Neoplasias de la Base del Cráneo/diagnóstico por imagen , Resonancia por Plasmón de Superficie , Oncología Médica , Cráneo , Diagnóstico por Imagen
4.
Pediatr Radiol ; 53(4): 576-580, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35731260

RESUMEN

A new task force dedicated to artificial intelligence (AI) with respect to paediatric radiology was created in 2021 at the International Paediatric Radiology (IPR) meeting in Rome, Italy (a joint society meeting by the European Society of Pediatric Radiology [ESPR] and the Society for Pediatric Radiology [SPR]). The concept of a separate task force dedicated to AI was borne from an ESPR-led international survey of health care professionals' opinions, expectations and concerns regarding AI integration within children's imaging departments. In this survey, the majority (> 80%) of ESPR respondents supported the creation of a task force and helped define our key objectives. These include providing educational content about AI relevant for paediatric radiologists, brainstorming ideas for future projects and collaborating on AI-related studies with respect to collating data sets, de-identifying images and engaging in multi-case, multi-reader studies. This manuscript outlines the starting point of the ESPR AI task force and where we wish to go.


Asunto(s)
Inteligencia Artificial , Radiología , Niño , Humanos , Radiología/métodos , Radiólogos , Encuestas y Cuestionarios , Sociedades Médicas
5.
Am J Perinatol ; 40(9): 1013-1025, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37336220

RESUMEN

Antenatal diagnosis of placenta accreta spectrum (PAS) improves maternal and neonatal outcomes by allowing for multidisciplinary planning and preparedness. Ultrasound is the primary imaging tool. Simplification and standardization of placental evaluation and reporting terminology allows improved communication and understanding between teams. Prior to 10 weeks of gestation, gestational sac position and least myometrial thickness surrounding the gestational sac help PAS diagnosis very early in pregnancy. Late first-, second-, and third-trimester evaluation includes comprehensive evaluation of the placenta, transabdominal and transvaginal with partially full maternal urinary bladder, and by color Doppler. Subsequently, the sonologist should indicate whether the evaluation was optimal or suboptimal; the level of suspicion as low, moderate, or high; and the extent as focal, global, or extending beyond the uterus. Other complementary imaging modalities such as 3D-power Doppler ultrasound, magnetic resonance imaging (MRI), and vascular topography mapping strive to improve antenatal placental evaluation but remain investigational at present. KEY POINTS: · Antenatal imaging, primarily using ultrasound with partially full maternal urinary bladder, is an essential means of evaluation of those at risk for PAS.. · Simplification and standardization of placental evaluation and reporting will allow improved communication between the multidisciplinary teams.. · Gestational sac location prior to 10 weeks of gestation and four markers after that (placental lacunae and echostructure, myometrial thinning, hypoechoic zone with or without bulging between placenta and myometrium, and increased flow on color Doppler)..


Asunto(s)
Placenta Accreta , Recién Nacido , Embarazo , Femenino , Humanos , Placenta Accreta/patología , Placenta/diagnóstico por imagen , Placenta/patología , Ultrasonografía Prenatal/métodos , Útero/patología , Diagnóstico Prenatal/métodos
6.
Pediatr Neurosurg ; 58(5): 240-258, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37604135

RESUMEN

BACKGROUND: Neuroimaging has evolved from anatomical imaging toward a multi-modality comprehensive anatomical and functional imaging in the past decades, important functional data like perfusion-weighted imaging, permeability imaging, diffusion-weighted imaging (DWI), and diffusion tensor imaging (DTI), tractography, metabolic imaging, connectomics, event-related functional imaging, resting state functional imaging, and much more is now being offered. SUMMARY: Precision diagnostics has proven to be essential for precision treatment. Many minimal invasive techniques have been developed, taking advantage of digital subtraction angiography and interventional neuroradiology. Furthermore, intraoperative CT and/or MRI and more recently MR-guided focused ultrasound have complemented the diagnostic and therapeutic armamentarium. KEY MESSAGES: In the current manuscript, we discuss standard imaging sequences including advanced techniques like DWI, DTI, susceptibility-weighted imaging, and 1H magnetic resonance spectroscopy, various perfusion weighted imaging approaches including arterial spin labeling, dynamic contrast enhanced imaging, and dynamic susceptibility contrast imaging. Pre-, intra, and postoperative surgical imaging including visualize imaging will be discussed. The value of connectomics will be presented for its value in neuro-oncology. Minimal invasive therapeutic possibilities of interventional neuroradiology and image-guided laser ablation and MR-guided high-intensity-focused ultrasound will be presented for treatment of pediatric brain and spinal cord tumors. Finally, a comprehensive review of spinal cord tumors and matching neuropathology has been included.


Asunto(s)
Imagen de Difusión Tensora , Neoplasias de la Médula Espinal , Humanos , Niño , Imagen de Difusión Tensora/métodos , Imagen por Resonancia Magnética/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias de la Médula Espinal/diagnóstico por imagen , Neoplasias de la Médula Espinal/cirugía , Encéfalo/diagnóstico por imagen , Encéfalo/cirugía , Médula Espinal/diagnóstico por imagen , Médula Espinal/cirugía
7.
Neuropediatrics ; 53(3): 195-199, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34674207

RESUMEN

We report on the conventional and diffusion tensor imaging (DTI) findings of a 2-year-old child with clinical presentation of Joubert's Syndrome (JS) and brainstem structural abnormalities as depicted by neuroimaging.Conventional magnetic resonance imaging (MRI) showed a "molar tooth" configuration of the brainstem. A band-like formation coursing in an apparent axial plane anterior to the interpeduncular fossa was noted and appeared to partially cover the interpeduncular fossa.DTI maps and three-dimensional (3D) tractography demonstrated a prominent red-encoded white matter bundle anterior to the midbrain. Probable aberrant course of the bilateral corticospinal tracts (CST) was also depicted. Absence of the decussation of the superior cerebellar peduncles and elongated thickened, horizontal superior cerebellar peduncle (SCP) reflecting the molar tooth sign were also shown.Our report and the review of the published cases suggest that DTI and tractography may be very helpful to differentiate between interpeduncular heterotopias and similarly located white matter bundles corroborating the underlying etiology of axonal guidance disorders in the complex group of ciliopathies including JS. Our case represents an important additional puzzle piece to explore the variability of these ciliopathies.


Asunto(s)
Anomalías Múltiples , Ciliopatías , Anomalías del Ojo , Enfermedades Renales Quísticas , Malformaciones del Sistema Nervioso , Anomalías Múltiples/patología , Cerebelo/anomalías , Cerebelo/patología , Preescolar , Ciliopatías/patología , Imagen de Difusión Tensora , Anomalías del Ojo/diagnóstico por imagen , Anomalías del Ojo/patología , Humanos , Enfermedades Renales Quísticas/diagnóstico por imagen , Enfermedades Renales Quísticas/patología , Malformaciones del Sistema Nervioso/patología , Retina/anomalías
8.
Prenat Diagn ; 42(4): 484-494, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34984691

RESUMEN

OBJECTIVES: To characterize a suggestive prenatal imaging pattern of Aicardi syndrome using ultrasound and MR imaging. METHODS: Based on a retrospective international series of Aicardi syndrome cases from tertiary centers encountered over a 20-year period (2000-2020), we investigated the frequencies of the imaging features in order to characterize an imaging pattern highly suggestive of the diagnosis. RESULTS: Among 20 cases included, arachnoid cysts associated with a distortion of the interhemispheric fissure were constantly encountered associated with complete or partial agenesis of the corpus callosum (19/20, 95%). This triad in the presence of other CNS disorganization, such as polymicrogyria (16/17, 94%), heterotopias (15/17, 88%), ventriculomegaly (14/20, 70%), cerebral asymmetry [14/20, 70%]) and less frequently extra-CNS anomaly (ocular anomalies [7/11, 64%], costal/vertebral segmentation defect [4/20, 20%]) represent a highly suggestive pattern of Aicardi syndrome in a female patient. CONCLUSION: Despite absence of genetic test to confirm prenatal diagnosis of AS, this combination of CNS and extra-CNS fetal findings allows delineation of a characteristic imaging pattern of AS, especially when facing dysgenesis of the corpus callosum.


Asunto(s)
Síndrome de Aicardi , Malformaciones del Sistema Nervioso , Agenesia del Cuerpo Calloso/diagnóstico por imagen , Síndrome de Aicardi/diagnóstico por imagen , Cuerpo Calloso/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Malformaciones del Sistema Nervioso/diagnóstico por imagen , Embarazo , Diagnóstico Prenatal/métodos , Estudios Retrospectivos , Ultrasonografía Prenatal/métodos
9.
Childs Nerv Syst ; 38(5): 977-984, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35305115

RESUMEN

PURPOSE: Few studies report radiologic and clinical outcome of post-hemorrhagic isolated fourth ventricle (IFV) with focus on surgical versus conservative management in neonates and children. Our aim is to investigate differences in radiological and clinical findings of IFV between patients who had surgical intervention versus patients who were treated conservatively. METHODS: A retrospective analysis of patients diagnosed with IFV was performed. Data included demographics, clinical exam findings, surgical history, and imaging findings (dilated FV extent, supratentorial ventricle dilation, brainstem and cerebellar deformity, tectal plate elevation, basal cistern and cerebellar hemisphere effacement, posterior fossa upward/downward herniation). RESULTS: Sixty-four (30 females) patients were included. Prematurity was 94% with 90% being < 28 weeks of gestation. Mean age at first ventricular shunt was 3.6 (range 1-19); at diagnosis of IFV, post-lateral ventricular shunting was 26.2 (1-173) months. Conservatively treated patients were 87.5% versus 12.5% treated with FV shunt/endoscopic fenestration. Severe FV dilation (41%), severe deformity of brainstem (39%) and cerebellum (47%) were noted at initial diagnosis and stable findings (34%, 47%, and 52%, respectively) were seen at last follow-up imaging. FV dilation (p = 0.0001) and upward herniation (p = 0.01) showed significant differences between surgery versus conservative management. No other radiologic or clinical outcome parameters were different between two groups. CONCLUSION: Only radiologic outcome results showed stable or normal FV dilation and stable or decreased upward herniation in the surgically treated group.


Asunto(s)
Cuarto Ventrículo , Hidrocefalia , Tronco Encefálico , Niño , Femenino , Cuarto Ventrículo/diagnóstico por imagen , Cuarto Ventrículo/cirugía , Humanos , Hidrocefalia/diagnóstico por imagen , Hidrocefalia/etiología , Hidrocefalia/cirugía , Recién Nacido , Masculino , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
10.
Pol J Radiol ; 87: e363-e368, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35979155

RESUMEN

Purpose: Retinoblastoma (RB) is the most common intraocular malignancy of childhood. Magnetic resonance imaging (MRI) is essential for initial diagnosis, tumour extension, staging, and treatment planning of RB. Awareness of neuro-imaging findings and determining local extent are essential for early diagnosis and therapy guidance. The purpose of this study is to evaluate and to provide a detailed list of neuroimaging features of RB to improve the diagnostic work-up of children with RB. Material and methods: Retrospective review was performed among children with confirmed RB diagnosis. MRI features were identified to evaluate: 1) growth pattern; 2) intraocular extension; 3) extraocular extension; 4) central nervous system disease; 5) conventional MRI characteristics of the RB lesions; and 6) DWI and ADC characteristics. These features were compared between unilateral and bilateral RB lesions. Results: Twenty-four children (male/female: 18/6) were included in this study. The mean age at the time of diagnosis was 14.7 (11.4) months. In total, 34 RB lesions (bilateral = 18) were evaluated for the study. The most common features on MRI were: 1) endophytic RB lesion (50%); 2) subretinal haemorrhage (38%); 3) scleral involvement (3%); 4) leptomeningeal disease (12%); 5) contrast enhancement (97%); and 6) restricted diffusion (88%). The mean ADC value was 0.64 (0.15) × 10-3 mm2/s. Choroidal invasion (p = 0.05) and scleral involvement (p = 0.04) were significantly higher for bilateral RB lesions. Conclusions: Contrast enhancement and restricted diffusion are the most common neuroimaging features of RB. Choroidal invasion and scleral involvement are more frequently seen in bilateral disease.

11.
Pediatr Blood Cancer ; 68(3): e28778, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33089644

RESUMEN

Central giant cell granuloma (CGCG) is a benign but locally aggressive intraosseous lesion of the mandible. Historically, it is treated by curettage or resection. Medical therapy is indicated when surgery is associated with increased morbidity or in adjuvant setting to decrease recurrence. Treatment of CGCG with denosumab, a receptor activator of nuclear factor kappa-beta (RANK) ligand inhibitor, is not well studied, especially in children. Here, we describe our experience with the use of denosumab in the treatment of six children with CGCG. All patients had a favorable response with manageable side effects, which suggests that denosumab is an effective treatment option without increased morbidity.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Denosumab/uso terapéutico , Granuloma de Células Gigantes/tratamiento farmacológico , Niño , Preescolar , Femenino , Estudios de Seguimiento , Granuloma de Células Gigantes/patología , Humanos , Masculino , Pronóstico
12.
Prenat Diagn ; 41(8): 965-971, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34145612

RESUMEN

OBJECTIVE: To determine the impact of the lesion type (cystic [myelomeningocele] or flat [myeloschisis]) on the fetal motor function (MF) in cases candidates for prenatal open neural tube defect (ONTD) repair. METHODS: Retrospective cohort study of patients with ONTD who underwent prenatal repair at a single institution between 2011 and 2019. The lesion type and the measurements of the length and width of the lesions to calculate the surface of the ellipsoid lesion were performed using MR scans. Prenatal MF of the lower extremities was evaluated by ultrasound following a metameric distribution at the time of referral. Intact MF was defined as the observation of plantar flexion of the ankle. Logistic regression was performed to determine the predictive value of the type of lesion for having an intact MF at the time of referral. RESULTS: 103 patients were included at 22.9 (19-25.4) weeks; 65% had cystic and 35% had flat lesions. At the time of referral, there was a higher proportion of cases with an intact MF in the presence of flat lesions (34/36; 94.4%) as compared to cystic lesion (48/67; 71.6%, p < 0.01). When adjusting for gestational age and anatomical level of the lesion, flat ONTD were 3.1 times more likely to be associated by intact motor function (CI%95 [2.1-4.6], p < 0.01) at the time of referral. CONCLUSION: Cystic ONTD are more likely to be associated with impaired MF at mid-gestation in candidates for prenatal ONTD repair.


Asunto(s)
Feto/anomalías , Estado Funcional , Defectos del Tubo Neural/complicaciones , Adulto , Estudios de Cohortes , Femenino , Feto/fisiopatología , Feto/cirugía , Edad Gestacional , Humanos , Defectos del Tubo Neural/fisiopatología , Embarazo , Estudios Retrospectivos , Estadísticas no Paramétricas
13.
J Neuroophthalmol ; 41(4): e598-e605, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33136667

RESUMEN

BACKGROUND: Severe visual impairment is present in nearly all infants with congenital Zika syndrome (CZS); however, ocular abnormalities are present only in a subset of these infants. The purpose of this study was to characterize the visual pathway abnormalities seen on computed tomography (CT) and MRI scans in infants with CZS. METHODS: Preliminary neuroimaging information was obtained from a referred sample of 105 infants with clinical and epidemiologic data consistent with CZS in the Pernambuco state of Brazil. Subjects were excluded if Zika virus infection was not confirmed by serologic or cerebrospinal fluid studies or if images were nondiagnostic. Of the 105 subjects initially screened, head CT images adequate for interpretation were available for 54, and brain MRI images adequate for interpretation were available for 20. Four patients had both CT and MRI images. Magnetic resonance imaging and CT scans from infants with CZS were systematically reviewed for globe malformations, optic nerve and chiasmal atrophy, occipital cortical volume loss, white matter abnormalities, ventriculomegaly, and calcifications. Neuroimaging findings were correlated with measures of visual function and with ocular examinations in these infants. RESULTS: Thirty-three males and 37 females were included in the analysis. The mean age of the infants at the time of neuroimaging was 16.0 weeks (range 0 days-15.5 months), and the mean gestational age at the time of birth was 38 weeks. All patients were from the Pernambuco state of Brazil. Overall, 70 of 74 (95%) scans showed occipital volume loss, whereas 9 (12%) showed optic nerve atrophy, 3 (4%) showed chiasmal atrophy, and 1 (1%) showed an ocular calcification. Sixty-two of the infants underwent ophthalmologic examinations. A total of 34 (55%) infants had at least one documented structural ocular abnormality, and 26 (42%) had at least one structural ocular abnormality documented in both eyes. Of those with available visual acuity data, all had visual impairment. Among those with visual impairment and normal eye examinations, 100% had visual pathway abnormalities on neuroimaging, including 100% with occipital cortical volume loss, 8% with optic nerve atrophy, and 8% with chiasmal atrophy. CONCLUSION: Our results suggest that cortical visual impairment related to structural abnormalities of the occipital cortex is likely an important cause of visual impairment in children with CZS with normal eye examinations.


Asunto(s)
Hidrocefalia , Microcefalia , Infección por el Virus Zika , Virus Zika , Niño , Femenino , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Microcefalia/diagnóstico , Tomografía Computarizada por Rayos X , Vías Visuales/diagnóstico por imagen , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/diagnóstico por imagen
14.
AJR Am J Roentgenol ; 215(6): 1417-1420, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32602344

RESUMEN

OBJECTIVE. The purpose of this article is to share an experience in the rapid deployment of home workstations that illustrates a creative solution that transcended typical administrative barriers. CONCLUSION. In response to the global coronavirus disease (COVID-19) pandemic, radiology departments need to rapidly deploy home PACS workstations to facilitate physical distancing and to guarantee radiologic expertise despite possible home quarantining or stay home, work safe orders.


Asunto(s)
COVID-19/epidemiología , Sistemas de Información Radiológica , Telerradiología/métodos , Eficiencia Organizacional , Humanos , Pandemias , Distanciamiento Físico , Cuarentena , SARS-CoV-2 , Estados Unidos/epidemiología , Flujo de Trabajo
15.
Magn Reson Med ; 82(3): 1129-1139, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31066104

RESUMEN

PURPOSE: Noninvasive measurement of cerebral venous oxygenation (Yv ) in neonates is important in the assessment of brain oxygen extraction and consumption, and may be useful in characterizing brain development and neonatal brain diseases. This study aims to develop a rapid method for vessel-specific measurement of Yv in neonates. METHODS: We developed a pulse sequence, named accelerated T2 -relaxation-under-phase-contrast (aTRUPC), which consists of velocity-encoding phase-contrast module to isolate pure blood signal, flow-insensitive T2 -preparation to quantify blood T2 , and turbo-field-echo (TFE) scheme for rapid image acquisition, which is critical for neonatal MRI. A series of studies were conducted. First, the pulse sequence was optimized in terms of TFE factor, velocity encoding (VENC), and slice thickness for best sensitivity. Second, to account for the influence of TFE acquisition on T2 quantification, simulation and experiments were conducted to establish the relationship between TFE-T2 and standard T2 . Finally, the complete aTRUPC sequence was applied on a group of healthy neonates and normative Yv values were determined. RESULTS: Optimal parameters of aTRUPC in neonates were found to be a TFE factor of 15, VENC of 5 cm/s, and slice thickness of 10 mm. The TFE-T2 was on average 3.9% lower than standard T2 . These two measures were strongly correlated (R2 = 0.86); thus their difference can be accounted for by a correction equation, T2,standard = 1.2002 × T2,TFE - 10.6276. Neonatal Yv values in veins draining cortical brain and those draining central brain were 64.8 ± 2.9% and 70.2 ± 3.3%, respectively, with a significant difference (P =.02). CONCLUSION: The aTRUPC MRI has the potential to provide vessel-specific quantification of cerebral Yv in neonates.


Asunto(s)
Encéfalo , Venas Cerebrales/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Oxígeno/sangre , Adulto , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Recién Nacido , Masculino , Oximetría , Adulto Joven
16.
NMR Biomed ; 32(7): e4103, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31038246

RESUMEN

There is increasing interest in applying physiological MRI in neonates, based on the premise that physiological parameters may provide an early biomarker of neonatal brain health and injury. Two commonly used techniques are oxygen extraction fraction (OEF) measurement using T2 -relaxation-under-spin-tagging (TRUST) MRI and cerebral blood flow measurement using phase-contrast (PC) quantitative flow MRI, which collectively provide an assessment of the brain's oxygen consumption. However, prior research has only demonstrated proof of principle of these methods in neonates, without characterization or benchmarking of the techniques. This is because available time is limited in neonatal subjects, especially when scans are performed as add-ons to clinical scans (typically less than 5 min). The work presented aims to examine the TRUST and PC MRI sequences systematically in normal neonates, through research-dedicated scan sessions. A series of characterization and optimization studies were conducted in a total of 26 radiographically normal neonates on 3 T systems. Our results show that TRUST MRI at the superior sagittal sinus (SSS) provides an OEF measurement equivalent to that at the internal jugular vein (r = 0.80, n = 10), yet with shorter scan time. Lower resolution provided better precision in the TRUST measurement (p = 0.001, n = 9). Therefore, the preferred OEF measurement is to apply TRUST MRI at the SSS using a spatial resolution of 2.5 mm. For PC MRI, our results showed that non-gated PC MRI yielded blood flow measurements comparable to those from the more time-consuming gated approach in neonates (r = 0.89, n = 7). It was also found that blood flow could be overestimated by 18% when imaging resolution is larger than 0.3 mm (n = 7). Therefore, non-gated PC MRI with a spatial resolution of 0.3 mm is recommended for neonatal applications. In conclusion, this study verifies consistency of neonatal brain oxygenation and flow measurements across acquisition schemes and points to optimal strategies in parameter selection when using these sequences.


Asunto(s)
Encéfalo/irrigación sanguínea , Circulación Cerebrovascular/fisiología , Imagen por Resonancia Magnética , Oxígeno/metabolismo , Femenino , Humanos , Recién Nacido , Masculino , Marcadores de Spin
18.
J Ultrasound Med ; 38(8): 2025-2038, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30560547

RESUMEN

OBJECTIVES: To investigate whether quantitative contrast-enhanced ultrasound (CEUS) can accurately identify neonates and infants with hypoxic ischemic brain injury. METHODS: In this prospective cohort study, 8 neonates and infants with a suspicion of hypoxic ischemic injury were evaluated with CEUS. RESULTS: An interesting trend was observed in the central gray nuclei-to-cortex perfusion ratios. The ratios at the peak enhancement, wash-in area under the curve, perfusion index, and maximum wash-in slopes were lower in all of the affected cases compared to the normal group but not statistically significant given the small sample size (P = .0571). Additionally, when the central gray nuclei-to-cortex perfusion ratio was plotted for all time points along the time-intensity curve, it was observed that the affected cases showed a trend that was qualitatively different from that of the normal cases. In the affected cases, the ratio time-intensity curves either stayed below 1.0 for the entire enhancement period or reached 1.0 close to peak wash-in before falling just below 1.0 for the remaining period of enhancement. However, in the unaffected patients, there was a steep wash-in that crossed the 1.0 threshold and remained above 1.0 for most of the enhancement period. CONCLUSIONS: Bedside CEUS is an easily obtainable brain-imaging modality that has the potential to effectively identify infants and neonates with evolving brain injury. A larger prospective study evaluating the correlation between CEUS findings and the reference standard of diffusion- and perfusion-weighted magnetic resonance imaging is needed to establish it as a diagnostic tool.


Asunto(s)
Medios de Contraste , Hipoxia-Isquemia Encefálica/diagnóstico por imagen , Aumento de la Imagen/métodos , Ultrasonografía/métodos , Encéfalo/diagnóstico por imagen , Estudios de Cohortes , Estudios de Evaluación como Asunto , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Reproducibilidad de los Resultados
19.
J Neuroradiol ; 46(3): 214-221, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30423378

RESUMEN

BACKGROUND AND PURPOSE: The vein of Galen aneurysmal malformation (VGAM) is a rare congenital vascular malformation with a higher morbidity and mortality, especially in neonates. Ultrasound, CT and MR are usually used in diagnosis and treatment monitoring of these disorders. In this current study, we aim to examine utility of SWI in evaluation of treatment response in infants with VGAM. MATERIALS AND METHODS: We performed a retrospective chart analysis of children with VGAM in our institution between January 2008 and December 2016. Inclusion criteria included; confirmed VGAM on DSA; available SWI sequence at baseline and at follow up after at least a single embolization session; age at initial MR of 18 years or younger. Signal intensity and Angioarchitecture of VGAM and cerebral veins on SWI, as well as hydrocephalus and clinical outcome were evaluated. RESULTS: Of 11 patients identified with VGAM in our institution, 5 children (3 males and 2 females) satisfied the inclusion criteria. The average age at initial MR was 29 days (range 1-120). Fourteen MRI were available for review. All children had VGAM of mural type. Intramedullary veins were dilated and SWI-hypointense in all children, while subependymal and sulcal veins were dilated and SWI-hypointense in 4 patients on initial MRI. On the first available follow up MRI, cerebral veins have mostly normalized in 4 children and remained mostly dilated and SWI-hypointense in 1 child; even after complete treatment of the VGAM. CONCLUSION: Our preliminary findings show that SWI seems to offer a beneficial non-invasive tool in evaluating passive venous congestion patterns in pediatric patients with VGAM. It remains to be determined in larger studies, the clinical significance of these SWI changes.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Malformaciones de la Vena de Galeno/diagnóstico por imagen , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos
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