Richard L Robertson

Boston Children's Hospital, Boston, Massachusetts, United States

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Publications (71)294.84 Total impact

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    ABSTRACT: OBJECT Moyamoya can cause cerebral ischemia and stroke in Down syndrome (DS) patients. In this study, the authors defined a surgically treated population of patients with DS and moyamoya and compared their clinical presentation, response to surgical treatment, and long-term prognosis with those of the general population of patients with moyamoya but without DS. METHODS This study was a retrospective review of a consecutive operative series of moyamoya patients with DS treated at Boston Children's Hospital from 1985 through 2012. RESULTS Thirty-two patients, average age 9.7 years (range 1.8-29.3 years), underwent surgery for moyamoya in association with DS. The majority presented with ischemic symptoms (87% stroke, 42% transient ischemic attacks). Twenty-four patients (75%) had congenital heart disease. Nineteen patients (59%) had bilateral moyamoya on presentation, and 13 presented with unilateral disease, of which 2 progressed to surgery on the opposite side at a later date. Patients were followed for a median of 7.5 years (1-20.2 years) after surgery, with no patients lost to follow-up. Follow-up arteriography demonstrated Matsushima Grade A collaterals in 29 of 39 (74%) hemispheres, Grade B in 5 (13%), and Grade C in 5 (13%). Complications included postoperative strokes in 2 patients, which occurred within 48 hours of surgery in both; one of these patients had arm weakness and the other confusion (both had recovered completely at follow-up). Seizures occurred in 5 patients perioperatively, including one who had a new seizure disorder related to hypocalcemia. CONCLUSIONS Moyamoya disease is a cause of stroke in patients with DS. Both the incidence of preoperative stroke (87% vs 67%) and the average age at diagnosis for children under age 21 (8.4 vs 6.5 years) were greater in patients with DS and moyamoya than in the general moyamoya surgical population, suggesting a possible delay in reaching a correct diagnosis of the cause of cerebral ischemia in the DS patient population. Pial synangiosis provided long-term protection from stroke in all patients treated.
    Journal of Neurosurgery Pediatrics 04/2015; DOI:10.3171/2014.12.PEDS14563 · 1.37 Impact Factor
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    ABSTRACT: Fetal magnetic resonance imaging (MRI) examinations have become well-established procedures at many institutions and can serve as useful adjuncts to ultrasound (US) exams when diagnostic doubts remain after US. Because of fetal motion, however, fetal MRI exams are challenging and require the MR scanner to be used in a somewhat different mode than that employed for more routine clinical studies. Herein we review the techniques most commonly used, and those that are available, for fetal MRI with an emphasis on the physics of the techniques and how to deploy them to improve success rates for fetal MRI exams. By far the most common technique employed is single-shot T2-weighted imaging due to its excellent tissue contrast and relative immunity to fetal motion. Despite the significant challenges involved, however, many of the other techniques commonly employed in conventional neuro- and body MRI such as T1 and T2*-weighted imaging, diffusion, and perfusion weighted imaging, as well as spectroscopic methods remain of interest for fetal MR applications. An effort to understand the strengths and limitations of these basic methods within the context of fetal MRI is made in order to optimize their use and facilitate implementation of technical improvements for the further development of fetal MR imaging, both in acquisition and post-processing strategies. © 2015 Wiley Periodicals, Inc. Concepts Magn Reson Part A, 2015.
    Concepts in Magnetic Resonance Part A 03/2015; DOI:10.1002/cmr.a.21321 · 1.00 Impact Factor
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    ABSTRACT: Brain injury is a major complication in neonates with complex congenital heart disease. Preliminary evidence suggests that fetuses with congenital heart disease are at greater risk for brain abnormalities. However, the nature and frequency of these brain abnormalities detected by conventional fetal MR imaging has not been examined prospectively. Our primary objective was to determine the prevalence and spectrum of brain abnormalities detected on conventional clinical MR imaging in fetuses with complex congenital heart disease and, second, to compare the congenital heart disease cohort with a control group of fetuses from healthy pregnancies. We prospectively recruited pregnant women with a confirmed fetal congenital heart disease diagnosis and healthy volunteers with normal fetal echocardiogram findings who underwent a fetal MR imaging between 18 and 39 weeks gestational age. A total of 338 fetuses (194 controls; 144 with congenital heart disease) were studied at a mean gestational age of 30.61 ± 4.67 weeks. Brain abnormalities were present in 23% of the congenital heart disease group compared with 1.5% in the control group (P < .001). The most common abnormalities in the congenital heart disease group were mild unilateral ventriculomegaly in 12/33 (36.4%) and increased extra-axial spaces in 10/33 (30.3%). Subgroup analyses comparing the type and frequency of brain abnormalities based on cardiac physiology did not reveal significant associations, suggesting that the brain abnormalities were not limited to those with the most severe congenital heart disease. This is the first large prospective study reporting conventional MR imaging findings in fetuses with congenital heart disease. Our results suggest that brain abnormalities are prevalent but relatively mild antenatally in fetuses with congenital heart disease. The long-term predictive value of these findings awaits further study.
    American Journal of Neuroradiology 03/2014; DOI:10.3174/ajnr.A3903 · 3.68 Impact Factor
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    ABSTRACT: Background: Few data are available on the neuropsychological, behavioural, or structural brain imaging outcomes in adolescents who underwent corrective surgery in infancy for tetralogy of Fallot. Methods: In this single-centre cross-sectional study, we enrolled 91 adolescents (13-16 years old) with tetralogy of Fallot and 87 referent subjects. Assessments included tests of academic achievement, memory, executive functions, visual-spatial skills, attention, and social cognition, as well as brain magnetic resonance imaging. Results: Genetic abnormalities or syndromes were present in 25% of tetralogy of Fallot patients, who had markedly greater neuropsychological morbidities than did patients without a syndrome. However, even patients without a syndrome performed significantly worse than the referent group or population norms in all of the neuropsychological domains assessed. In multivariable regression in those without a genetic/phenotypic syndrome, the strongest predictors of adverse late neurodevelopmental outcomes included a greater number of complications at the first operation, more total surgical complications across all operations, and occurrence of post-operative seizures. The presence of at least one abnormality on structural magnetic resonance imaging was more frequent in tetralogy of Fallot patients than the referent group (42% versus 8%). Conclusions: Adolescents with tetralogy of Fallot are at increased neurodevelopmental risk and would benefit from ongoing surveillance and educational supports even after childhood.
    Cardiology in the Young 02/2014; 25(02):1-10. DOI:10.1017/S1047951114000031 · 0.86 Impact Factor
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    ABSTRACT: Isolated inferior vermian hypoplasia (iiVH) is one of the most common fetal cerebellar anomalies presenting for fetal neurological counselling with controversial postnatal neurodevelopmental outcome. In the present study, we characterised the long-term neurodevelopmental outcome of prenatally diagnosed iiVH at school age. We prospectively followed 20 children with fetal MRI diagnosis of iiVH including their postnatal MRI result and developmental outcome at school age (mean 6.1 years±1.9 years SD) using a comprehensive age-appropriate developmental testing battery, which encompassed cognitive, language, social and behavioural domains. Parental stress level and socioeconomic status were also evaluated. All children with postnatally confirmed iiVH had a normal neurodevelopmental outcome. A subgroup of children (2/20) who demonstrated cognitive delays and behavioural impairments had more extensive cerebellar malformation. Despite a normal developmental outcome, the parents of children with postnatally confirmed iiVH had higher parental stress compared with those parents whose children had normal postnatal MRI. Children with postnatally confirmed iiVH show age appropriate functioning at school age. Postnatal MRI is important to confirm the diagnosis of iiVH and to exclude associated anomalies that impact neurodevelopmental outcome. A diagnosis of iiVH is associated with persistent elevated parental stress despite normal developmental outcomes in these children suggesting the need for ongoing parental support.
    Archives of Disease in Childhood - Fetal and Neonatal Edition 08/2013; DOI:10.1136/archdischild-2013-304054 · 3.86 Impact Factor
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    ABSTRACT: OBJECTIVE. The purpose of this article is to describe the imaging features of different types of surgical cerebral revascularization techniques. CONCLUSION. Surgical cerebral revascularization involves direct and indirect techniques. Direct revascularization entails anastomosing a branch of the external carotid artery to a cerebral artery. Indirect revascularization involves delivering an extracranial vascular supply in proximity to the surface of the brain. The results of these techniques have distinctive imaging features.
    American Journal of Roentgenology 07/2013; 201(1):W124-32. DOI:10.2214/AJR.12.9517 · 2.74 Impact Factor
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    ABSTRACT: BACKGROUND: The experience in the newborn intensive care nursery results in premature infants' neurobehavioral and neurophysiological dysfunction and poorer brain structure. Preterms with severe intrauterine growth restriction are doubly jeopardized given their compromised brains. The Newborn Individualized Developmental Care and Assessment Program improved outcome at early school-age for preterms with appropriate intrauterine growth. It also showed effectiveness to nine months for preterms with intrauterine growth restriction. The current study tested effectiveness into school-age for preterms with intrauterine growth restriction regarding executive function (EF), electrophysiology (EEG) and neurostructure (MRI). METHODS: Twenty-three 9-year-old former growth-restricted preterms, randomized at birth to standard care (14 controls) or to the Newborn Individualized Developmental Care and Assessment Program (9 experimentals) were assessed with standardized measures of cognition, achievement, executive function, electroencephalography, and magnetic resonance imaging. The participating children were comparable to those lost to follow-up, and the controls to the experimentals, in terms of newborn background health and demographics. All outcome measures were corrected for mother's intelligence. Analysis techniques included two-group analysis of variance and stepwise discriminate analysis for the outcome measures, Wilks' lambda and jackknifed classification to ascertain two-group classification success per and across domains; canonical correlation analysis to explore relationships among neuropsychological, electrophysiological and neurostructural domains at school-age, and from the newborn period to school-age. RESULTS: Controls and experimentals were comparable in age at testing, anthropometric and health parameters, and in cognitive and achievement scores. Experimentals scored better in executive function, spectral coherence, and cerebellar volumes. Furthermore, executive function, spectral coherence and brain structural measures discriminated controls from experimentals. Executive function correlated with coherence and brain structure measures, and with newborn-period neurobehavioral assessment. CONCLUSION: The intervention in the intensive care nursery improved executive function as well as spectral coherence between occipital and frontal as well as parietal regions. The experimentals' cerebella were significantly larger than the controls'. These results, while preliminary, point to the possibility of long-term brain improvement even of intrauterine growth compromised preterms if individualized intervention begins with admission to the NICU and extends throughout transition home. Larger sample replications are required in order to confirm these results.Clinical trial registration: The study is registered as a clinical trial. The trial registration number is NCT00914108.
    BMC Pediatrics 02/2013; 13(1):25. DOI:10.1186/1471-2431-13-25 · 1.92 Impact Factor
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    ABSTRACT: OBJECTIVE: Our objective was to use diffusion tensor imaging (DTI) to compare white matter microstructure in adolescents with d-transposition of the great arteries (d-TGA) who underwent the arterial switch operation in early infancy with typically developing control adolescents. We also examined correlates between patient demographic and medical risk factors and white matter as assessed by regional fractional anisotropy (FA) values. METHODS: We used with magnetic resonance imaging (MRI) to study 49 adolescents with d-TGA and 29 control adolescents. MRI data, including whole brain DTI and conventional anatomic MRI, were acquired from each subject. Each subject's data were analyzed using random effects analysis to evaluate regional white matter differences in FA between d-TGA and control adolescents. RESULTS: While multifocal punctate MRI hypointensities on T1-weighted (T1W) imaging suggestive of mineralization were found, other evidence of gross white matter injury was absent. Eighteen discrete regions of significantly reduced FA in d-TGA adolescents compared with controls were observed in deep white matter of cerebral hemispheres, cerebellum, and midbrain. Among d-TGA adolescents, lower FA correlated with younger gestational age, shorter duration of intraoperative cooling, higher intraoperative minimum tympanic temperature, longer intensive care unit stay after repair, and greater total number of open cardiac operations. CONCLUSIONS: Despite scant white matter injury evident on conventional brain MRI, adolescents with d-TGA repaired in infancy demonstrate significant white matter FA reduction that may relate to their reported neurocognitive deficits. Among adolescents with d-TGA, FA values are associated with patient and perioperative factors, some of which are modifiable.
    The Journal of thoracic and cardiovascular surgery 01/2013; 146(3). DOI:10.1016/j.jtcvs.2012.12.006 · 3.99 Impact Factor
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    ABSTRACT: Object Chorea is a movement disorder characterized by brief, irregular, involuntary contractions that appear to flow from 1 muscle to another. There are a limited number of reports in the literature that have linked moyamoya disease and chorea. The authors describe their experience in treating moyamoya disease in patients in whom chorea developed as part of the clinical presentation. Methods The authors conducted a retrospective review of a consecutive series of 316 children who underwent pial synangiosis revascularization for moyamoya disease at the Boston Children's Hospital. Results Of 316 surgically treated patients with moyamoya disease, 10 (3.2%; 6 boys and 4 girls) had chorea as a part of their presentation. The average age at surgical treatment was 9.9 years (range 3.8-17.9 years). All patients had evidence of hypertrophied lenticulostriate collateral vessels through the basal ganglia on preoperative angiography and/or MRI on affected sides. Two patients had cystic lesions in the basal ganglia. Nine patients underwent bilateral craniotomies for pial synangiosis, and 1 patient underwent a single craniotomy for unilateral disease. Follow-up was available in 9 patients (average 50.1 months). The mean duration of chorea was 1.36 years (range 2 days to 4 years), with resolution of symptoms in all patients. One patient developed chorea 3 years after surgical treatment, 4 patients had transient chorea that resolved prior to surgery, and 5 patients experienced resolution of the chorea after surgery (average 13 months). Conclusions The authors describe children with moyamoya disease and chorea as part of their clinical presentation. The data suggest that involvement of the basal ganglia by the hypertrophied collateral vessels contributes to the development of chorea, which can wax or wane depending on disease stage or involution of the vessels after revascularization surgery. In most patients, however, the chorea improves or disappears about 1 year after presentation.
    Journal of Neurosurgery Pediatrics 01/2013; 11(3). DOI:10.3171/2012.11.PEDS12199 · 1.37 Impact Factor
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    ABSTRACT: Cerebellar injury is an important complication of preterm birth with far-reaching neuropsychiatric sequelae. We have previously shown a significant association between isolated injury to the premature cerebellum and subsequent impairment of regional volumetric growth in the contralateral cerebrum. In the current study, we examine the relationship between these remote regional impairments of cerebral volumetric growth and domain-specific functional deficits in these children. In 40 ex-preterm infants with isolated cerebellar injury, we performed neurodevelopmental evaluations and quantitative magnetic resonance imaging (MRI) studies at a mean age of 34 months. We measured cortical gray matter volumes in 8 parcellated regions of each cerebral hemisphere, as well as right and left cerebellar volumes. We show highly significant associations between early signs of autism and dorsolateral prefrontal cortex volume (P < 0.001); gross motor scores and sensorimotor cortical volumes (P < 0.001); and cognitive and expressive language scores and premotor and mid-temporal cortical volumes (P < 0.001). By multivariate analyses, each unit increase in the corresponding regional cerebral volume was associated with lower odds of abnormal outcome score, adjusted for age at MRI and contralateral cerebellar volume. This is the first report linking secondary impairment of remote cerebral cortical growth and functional disabilities in survivors of prematurity-related cerebellar brain injury.
    Cerebral Cortex 11/2012; DOI:10.1093/cercor/bhs354 · 8.31 Impact Factor
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    ABSTRACT: The aim of this study was to compare total and regional cerebral volumes in children with isolated cerebellar malformations (CBMs) with those in typically developing children, and to examine the extent to which cerebellar volumetric reductions are associated with total and regional cerebral volumes. This is a case-control study of children diagnosed with isolated CBMs. Each child was matched on age and sex to two typically developing children. Using advanced three-dimensional volumetric magnetic resonance imaging, the cerebrum was segmented into tissue classes and partitioned into eight regions. Analysis of variance was used to compare cerebral volumes between children with CBMs and control children, and linear regressions to examine the impact of cerebellar volume reduction on cerebral volumes. Magnetic resonance imaging was performed at a mean age of 27 months in 20 children (10 males, 10 females) with CBMs and 40 typically developing children. Children with CBMs showed significantly smaller deep grey matter nuclei (p < 0.001), subgenual white matter (p = 0.03), midtemporal white matter (p = 0.02), and inferior occipital grey matter (p = 0.03) volumes than typically developing children. Greater cerebellar volumetric reduction in children with CBMs was associated with decreased total cerebral volume and deep grey matter nuclei (p = 0.02), subgenual white/grey matter (p = 0.001), midtemporal white (p = 0.02) and grey matter (p = 0.01), and parieto-occipital grey matter (p = 0.004). CBMs are associated with impaired regional cerebral growth, suggesting deactivation of principal cerebello-cerebral pathways.
    Developmental Medicine & Child Neurology 11/2011; 53(12):1128-34. DOI:10.1111/j.1469-8749.2011.04090.x · 3.29 Impact Factor
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    ABSTRACT: The cerebellum has recently been recognized for its role in high-order functions, including cognition, language, and behavior. Recent studies have also begun to describe a functional topography of the mature cerebellum that includes organization on a mediolateral axis. However, no study to date has examined the relationship between regional cerebellar volume and developmental disabilities in children with cerebellar malformations. The objective of this study was to estimate the extent to which total and regional cerebellar volumes are associated with developmental disabilities in a cohort of children with cerebellar malformations. Children aged 1 to 6 years with a diagnosis of cerebellar malformation underwent standardized outcome measures and quantitative magnetic resonance scanning. The cerebellum was parcellated into seven mediolateral zones (three for each hemisphere plus the vermis) for regional volume analysis. In children with cerebellar malformations, decreased total cerebellar volume was associated with delays in global development, expressive language, cognition, as well as gross and fine motor function. Decreased volume in the right lateral cerebellar hemisphere was related to impaired cognition, expressive language, and gross motor function. Additionally, reduced vermis volume was associated with impaired global development, cognition, expressive language, and gross and fine motor skills, as well as behavior problems and a higher rate of positive autism spectrum screening test. These results begin to define the structural topography of functional outcome in children with cerebellar malformations and should lead to greater accuracy of prognostication as well as timely early developmental interventions.
    The Cerebellum 09/2011; 11(2):531-42. DOI:10.1007/s12311-011-0312-z · 2.86 Impact Factor
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    ABSTRACT: We report neuropsychological and structural brain imaging assessments in children 16 years of age with d-transposition of the great arteries who underwent the arterial switch operation as infants. Children were randomly assigned to a vital organ support method, deep hypothermia with either total circulatory arrest or continuous low-flow cardiopulmonary bypass. Of 159 eligible adolescents, 139 (87%) participated. Academic achievement, memory, executive functions, visual-spatial skills, attention, and social cognition were assessed. Few significant treatment group differences were found. The occurrence of seizures in the postoperative period was the medical variable most consistently related to worse outcomes. The scores of both treatment groups tended to be lower than those of the test normative populations, with substantial proportions scoring ≥1 SDs below the expected mean. Although the test scores of most adolescents in this trial cohort are in the average range, a substantial proportion have received remedial academic or behavioral services (65%). Magnetic resonance imaging abnormalities were more frequent in the d-transposition of the great arteries group (33%) than in a referent group (4%). Adolescents with d-transposition of the great arteries who have undergone the arterial switch operation are at increased neurodevelopmental risk. These data suggest that children with congenital heart disease may benefit from ongoing surveillance to identify emerging difficulties. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000470.
    Circulation 08/2011; 124(12):1361-9. DOI:10.1161/CIRCULATIONAHA.111.026963 · 14.95 Impact Factor
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    ABSTRACT: The purpose of this study was to assess the conspicuity of brain cortical maturation with sonography and MRI of fetuses referred because of ventriculomegaly and to determine whether sulcal visualization can be used to predict postnatal outcome. Women with 374 fetuses referred because of ventriculomegaly underwent sonography and MRI. Four to six radiologists rated visualization of 19 fissures or sulci. Majority opinion regarding sulcal visualization was compared among fetuses categorized by CNS abnormality: normal, isolated ventriculomegaly, and ventriculomegaly with additional CNS abnormalities. Live-born infants were categorized as having normal or abnormal development. Logistic regression analysis was used to correlate sulcal visualization and postnatal development. A subanalysis was performed with fetuses who had been classified prenatally as having a normal brain or isolated ventriculomegaly. Cortical sulci were visualized more frequently and at an earlier gestational age with MRI than with ultrasound. In the entire cohort, the odds ratio of normal development ranged from 3.1 to 10.0 whenever the calcarine, parietooccipital, cingulate, superior temporal, precentral, or postcentral sulcus was seen on MR images. In fetuses categorized as having a normal brain or having isolated ventriculomegaly, the odds ratio of normal development ranged from 3.5 to 9.0 whenever the parietooccipital, cingulate, or superior temporal sulcus was seen. Visualization of the sulci in fetal brains depends on the imaging modality used and the gestational age at imaging. Information regarding sulcal visualization may aid in counseling patients carrying fetuses with ventriculomegaly.
    American Journal of Roentgenology 06/2011; 196(6):1457-67. DOI:10.2214/AJR.10.5422 · 2.74 Impact Factor
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    ABSTRACT: Advances in perinatal care and neuroimaging techniques have increased the detection of cerebellar malformations (CBMs) in the fetus and young infant. As a result, this has necessitated a greater understanding of the neurodevelopmental consequences of CBMs on child development. The aim of this study was to delineate the impact of CBMs on long-term neurodevelopmental outcomes. We conducted a cross-sectional study and systematically identified children with CBMs born between December 2000 and December 2006. We then performed follow-up magnetic resonance imaging studies, neurologic examination, and standardized neurodevelopmental outcome testing (Mullen Scales of Early Learning, Vineland Adaptive Behavior Scale, Child Behavior Checklist, Modified Checklist for Autism in Toddlers, and the Pediatric Quality of Life Inventory). Our sample comprised 49 children (29 males, 20 females; mean age, 28.4 mo, SD 16.4) with a CBM. Infants with evidence of acquired fetal or neonatal brain injury, intracranial birth trauma, inherited metabolic disease, or major pre- or postnatal cerebral ischemia were excluded. Our findings highlight that children with CBMs experience a high prevalence of neurologic, developmental, and functional disabilities including motor, cognitive, language, and social-behavioral deficits, as well as poor quality of life. The associated supratentorial anomalies, chromosomal findings, and malformations affecting the cerebellar vermis were significant independent predictors of neurodevelopmental disabilities in young children with CBMs. The associated supratentorial anomalies and chromosomal findings were also predictive of global developmental delay (p=0.01), cognitive impairment (p=0.03), gross and fine motor delay (p=0.02 and p=0.01 respectively), and positive screening for autism spectrum disorder (p=0.01). Additionally, malformations affecting the cerebellar vermis were significant independent predictors of expressive language (p=0.04) and gross motor delays (p=0.02). Developmental surveillance and early intervention programs should be an integral part of the long-term follow-up of survivors of CBM.
    Developmental Medicine & Child Neurology 03/2011; 53(5):409-16. DOI:10.1111/j.1469-8749.2011.03929.x · 3.29 Impact Factor
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    ABSTRACT: We report MRI findings from 2 pediatric clinical trials of diffuse intrinsic brainstem glioma (BSG) incorporating concurrent radiation therapy (RT) with molecularly targeted agents (gefitinib and tipifarnib). We determined associations of MRI variables with progression-free survival and overall survival and investigated effects of treatment on these variables. MRI (including diffusion and perfusion) was done before treatment, every 8 weeks (first year), every 12 weeks (thereafter), and at the end of treatment or disease progression. Reduced tumor volume (P < .0001) and tumor diffusion values (P <.0001) were apparent on the first post-RT/drug studies. Decreases in tumor volume correlated with pre-RT volume (P < .0001) and pre-RT diffusion values (P < .0001); larger decreases were noted for tumors with higher volumes and diffusion values. Patients with larger pre-RT tumors had longer progression-free survival (P < .0001). Patients with ≥ 25% decrease in tumor volume and diffusion values after RT had longer progression-free survival (P = .028) and overall survival (P = .0009). Enhancement at baseline and over time was significantly associated with shorter survival. Tumor diffusion values with baseline enhancement were significantly lower than those without (P = .0002). RT of BSG is associated with decreased tumor volume and intralesional diffusion values; patients with ≥ 25% decrease in values post-RT had relatively longer survival intervals, apparently providing an early imaging-based surrogate for relative outcomes. Patients with larger tumors and greater decreases in tumor volume and diffusion values had longer survival intervals. Tumor enhancement was associated with shorter survival, lower tumor diffusion values (increased cellularity), and a smaller drop in diffusion values after RT (P = .006). These associations justify continued investigation in other large clinical trials of brainstem glioma patients.
    Neuro-Oncology 02/2011; 13(4):417-27. DOI:10.1093/neuonc/noq200 · 5.29 Impact Factor
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    ABSTRACT: The objective of this study was to assess the outcomes of the prenatal diagnosis of septal leaflet abnormalities in fetuses referred for prenatal imaging with a finding of ventriculomegaly. This study is a retrospective review of fetuses with a diagnostic code of septal leaflet abnormalities from a larger prospective study. Four hundred twenty-five pregnant women with 433 fetuses referred for ventriculomegaly were imaged with ultrasound and MRI between July 1, 2003, and May 15, 2009. Four to six radiologists independently reviewed sonographic and MR images and recorded lateral ventricular diameters at the atrium and frontal horns, ventricular configuration, and the presence of ventriculomegaly and of other CNS abnormalities. Final prenatal ultrasound, MRI, and overall diagnoses were decided by consensus. Fetuses with a diagnostic code of septal leaflet abnormalities were identified, and birth outcome, autopsy findings, postnatal imaging, and postnatal follow-up examinations were obtained. The analysis of covariance, controlling for gestational age, was used to compare ventricular dimensions between fetuses with septal leaflet abnormalities and fetuses with isolated ventriculomegaly. Interrater agreement for the detection of septal leaflet abnormalities was assessed with kappa statistics. Interrater agreement and intrarater agreement for frontal horn measurements were assessed by variance components analysis. Twenty-three fetuses had septal leaflet abnormalities and 229 had isolated ventriculomegaly. Atrial and frontal horn diameters, adjusted for gestational age, were 77% and 98% larger, respectively, in fetuses with septal leaflet abnormalities than in fetuses with isolated ventriculomegaly (p < 0.0001). Before the consensus conference, agreement among ultrasound readers was moderate (κ = 0.54) and among MR readers, good (κ = 0.69). Additional CNS findings were seen on MRI in 12 of 23 fetuses (52%). Eleven pregnancies with septal leaflet abnormalities underwent termination and 12 progressed to livebirth; of the 12 livebirths, three neonates died. Neurodevelopmental follow-up was abnormal in all surviving children. A septal leaflet abnormality in the setting of ventriculomegaly is most frequently associated with other CNS abnormalities and is associated with postnatal developmental delay.
    American Journal of Roentgenology 01/2011; 196(1):W83-92. DOI:10.2214/AJR.10.4434 · 2.74 Impact Factor
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    ABSTRACT: The purposes of this feasibility study were to assess: (1) the potential utility of early brain MRI in asphyxiated newborns treated with hypothermia; (2) whether early MRI predicts later brain injury observed in these newborns after hypothermia has been completed; and (3) whether early MRI indicators of brain injury in these newborns represent reversible changes. All consecutive asphyxiated term newborns meeting the criteria for therapeutic hypothermia were enrolled prospectively. Each newborn underwent one or two early MRI scans while receiving hypothermia, on day of life (DOL) 1 and DOL 2-3 and also one or two late MRI scans on DOL 8-13 and at 1 month of age. 37 MRI scans were obtained in 12 asphyxiated neonates treated with induced hypothermia. Four newborns developed MRI evidence of brain injury, already visible on early MRI scans. The remaining eight newborns did not develop significant MRI evidence of brain injury on any of the MRI scans. In addition, two patients displayed unexpected findings on early MRIs, leading to early termination of hypothermia treatment. MRI scans obtained on DOL 2-3 during hypothermia seem to predict later brain injuries in asphyxiated newborns. Brain injuries identified during this early time appear to represent irreversible changes. Early MRI scans might also be useful to demonstrate unexpected findings not related to hypoxic-ischaemic encephalopathy, which could potentially be exacerbated by induced hypothermia. Additional studies with larger numbers of patients will be useful to confirm these results.
    Archives of Disease in Childhood - Fetal and Neonatal Edition 01/2011; 96(1):F36-44. DOI:10.1136/adc.2010.184291 · 3.86 Impact Factor
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    ABSTRACT: PURPOSE To assess postnatal outcomes of fetuses with agenesis or dysgenesis of the corpus callosum (ACC) after referral for ventriculomegaly (VM). METHOD AND MATERIALS In a prospective IRB-approved study from 7/2003 to 5/2009, 433 fetuses referred for VM were imaged with US and MRI. Five radiologists independently recorded ventricular diameter, ventricular configuration, degree of visualization of the corpus callosum, and CNS abnormalities, with final descriptions decided by consensus. Postnatal outcomes were obtained. RESULTS 58 fetuses had callosal abnormalities and 224 had isolated VM. Atrial diameter was 8-42 mm (mean 14.4 mm) in ACC and 9-19 mm (mean 11.5 mm) in isolated VM fetuses (p<0.0001). Frontal horn diameters were 1-22 mm (mean 4.4 mm) and 2-15 mm (mean 4.9 mm), respectively (p<0.0001). Pre-conference kappa for ACC among US readers was 0.86, among MR readers was 0.89, and among all readers was .87. 5/25 fetuses with isolated ACC by US had additional CNS abnormalities on MR. Fetuses with ACC were more likely to be described as having colpocephaly (58% by US, 81% by MR) compared to fetuses with isolated VM (0% by MR/US, p<0.00001). In fetuses with ACC, 33/58 (57%) had complete nonvisualization of the corpus callosum, and 15/58 (26%) had partial nonvisualization. In fetuses with isolated VM, these percentages were 0/224 (0%) and 7/224 (3%), respectively. 2/23 (9%) fetuses with isolated ACC, 13/35 (37%) fetuses with ACC and other CNS abnormalities, and 21/224 (9%) with isolated VM either underwent termination or died in utero or in the neonatal period. In 8/23 fetuses with isolated ACC on prenatal imaging, additional CNS abnormalities were present postnatally. Neurodevelopmental outcome was normal in 1/43 (2%) surviving children with ACC (the normal infant had isolated ACC), and 62/208 (30%) surviving children with isolated VM (p<0.00001). Degree of callosal visualization was not as important as presence of associated CNS abnormalities in predicting birth and developmental outcomes. CONCLUSION There is high inter-rater agreement in prenatal diagnosis of ACC. MR is more sensitive than US in diagnosis of ACC and in identifying CNS anomalies associated with ACC. Information regarding diagnosis and associated abnormalities influences pregnancy management. CLINICAL RELEVANCE/APPLICATION Knowledge of prenatal findings associated with ACC will aid in diagnosis, and knowledge of postnatal outcomes will aid in pregnancy counseling.
    Radiological Society of North America 2010 Scientific Assembly and Annual Meeting; 12/2010
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    ABSTRACT: Near-infrared spectroscopy monitoring of cerebral oxygen saturation (rSo(2)) has become routine in many centers, but no studies have reported the relationship of intraoperative near-infrared spectroscopy to long-term neurodevelopmental outcomes after cardiac surgery. Of 104 infants undergoing biventricular repair without aortic arch reconstruction, 89 (86%) returned for neurodevelopmental testing at 1 year of age. The primary near-infrared spectroscopy variable was the integrated rSo(2) (area under the curve) for rSo(2) <or=45%; secondary variables were the average and minimum rSo(2) by perfusion phase and at specific time points. Psychomotor and mental development indexes of the Bayley scales, head circumference, neurological examination, and abnormalities on brain magnetic resonance imaging did not differ between subjects according to a threshold level for rSo(2) of 45%. Lower Psychomotor Development Index scores were modestly associated with lower average (r=0.23, P=0.03) and minimum (r=0.22, P=0.04) rSo(2) during the 60-minute period after cardiopulmonary bypass but not with other perfusion phases. Hemosiderin foci on brain magnetic resonance imaging were associated with lower average rSo(2) from postinduction to 60 minutes post cardiopulmonary bypass (71+/-10% versus 78+/-6%, P=0.01) and with lower average rSO(2) during the rewarming phase (72+/-12% versus 83+/-9%, P=.003) and during the 60-minute period following cardiopulmonary bypass (65+/-11% versus 75+/-10%, P=0.009). In regression analyses that adjusted for age <or=30 days, Psychomotor Development Index score (P=0.02) and brain hemosiderin (P=0.04) remained significantly associated with rSo(2) during the 60-minute period following cardiopulmonary bypass. Perioperative periods of diminished cerebral oxygen delivery, as indicated by rSo(2), are associated with 1-year Psychomotor Development Index and brain magnetic resonance imaging abnormalities among infants undergoing reparative heart surgery. Clinical Trial Registration- URL: http://clinicaltrials.gov. Unique identifier: NCT00006183.
    Circulation 07/2010; 122(3):245-54. DOI:10.1161/CIRCULATIONAHA.109.902338 · 14.95 Impact Factor

Publication Stats

3k Citations
294.84 Total Impact Points

Institutions

  • 2004–2015
    • Boston Children's Hospital
      • Department of Radiology
      Boston, Massachusetts, United States
  • 2008–2013
    • Harvard University
      Cambridge, Massachusetts, United States
  • 2011
    • McGill University
      • Department of Neurology and Neurosurgery
      Montréal, Quebec, Canada
  • 1997–2011
    • Harvard Medical School
      • Department of Radiology
      Boston, Massachusetts, United States
  • 2005
    • Wolfson Childrens Hospital
      Jacksonville, Florida, United States
  • 1999
    • University of Massachusetts Boston
      Boston, Massachusetts, United States