1. Alhakeem E, Zavgorodni S. {{Poster – Thur Eve – 01: Development of simple and fast EBT2 film calibration procedure using PDD table}}. {Med Phys};2012 (Jul);39(7):4624.
Standard calibration procedure for EBT films is laborious and time-consuming. The objective of this work was to develop a simple and fast approach of EBT2 film calibration using PDD tables. EBT2 sheet is cut into 3 stripes of 5×25.5cm(2). The strips were exposed to dose of 600, 200 and 70cGy at d(max) each while placed horizontally in the middle of a 30x30x30cm(3) solid water phantom. Varian 21EX 6MV 10x10cm(2) beam was used with the gantry rotated to 90 degrees and SSD of 100cm to the phantom surface. After at least 24 hours, the films were digitized with flatbed scanner (Epson10000XL), according to a modified ISP scanning protocol. All images were analysed using an in-house Matlab code and ImageJ software. The net-optical densities against depths in the solid phantom were calibrated using PDD tables measured with ionization chamber for same machine. For verification, another calibration curve was generated for the same film batch following the same calibration protocol. Seven pieces of films were exposed to known doses and these doses were reconstructed using two derived calibration curves. The proposed approach was 3.6 times faster than the standard considering the number of films used in each methods, 3 stripes compared to11 pieces. The mean relative dose difference calculated for these films using the PDD calibration and the standard methods was 1.0+/-1.2% and 0.5+/-2.2% with maximum relative differences of 3.0% and 4.7% respectively. Our results show that PDD calibration approach is much easier, faster and predicts dose more reproducibly and accurately than the standard approach.
Lien vers le texte intégral (Open Access ou abonnement)
2. Alwinesh MT, Joseph RB, Daniel A, Abel JS, Shankar SR, Mammen P, Russell S, Russell PS. {{Psychometrics and utility of Psycho-Educational Profile-Revised as a developmental quotient measure among children with the dual disability of intellectual disability and autism}}. {J Intellect Disabil};2012 (Jul 25)
There is no agreement about the measure to quantify the intellectual/developmental level in children with the dual disability of intellectual disability and autism. Therefore, we studied the psychometric properties and utility of Psycho-Educational Profile-Revised (PEP-R) as a developmental test in this population. We identified 116 children with dual disability from the day care and inpatient database of a specialised Autism Clinic. Scale and domain level scores of PEP-R were collected and analyzed. We examined the internal consistency, domain-total correlation of PEP-R and concurrent validity of PEP-R against Gesell’s Developmental Schedule, inter-rater and test-retest reliability and utility of PEP-R among children with dual disability in different ages, functional level and severity of autism. Besides the adequate face and content validity, PEP-R demonstrates a good internal consistency (Cronbach’s alpha ranging from 0.91 to 0.93) and domain-total correlation (ranging from 0.75 to 0.90). The inter-rater reliability (intraclass correlation coefficient, ICC = 0.96) and test-retest reliability (ICC = 0.87) for PEP-R is good. There is moderate-to-high concurrent validity with GDS (r ranging from 0.61 to 0.82; all Ps = 0.001). The utility of PEP-R as a developmental measure was good with infants, toddlers, pre-school and primary school children. The ability of PEP-R to measure the developmental age was good, irrespective of the severity of autism but was better with high-functioning children. The PEP-R as an intellectual/developmental test has strong psychometric properties in children with dual disability. It could be used in children with different age groups and severity of autism. PEP-R should be used with caution as a developmental test in children with dual disability who are low functioning.
Lien vers le texte intégral (Open Access ou abonnement)
3. Aoki Y, Kasai K, Yamasue H. {{Age-related change in brain metabolite abnormalities in autism: a meta-analysis of proton magnetic resonance spectroscopy studies}}. {Transl Psychiatry};2012 (Feb 21);2:e69.
Abnormal trajectory of brain development has been suggested by previous structural magnetic resonance imaging and head circumference findings in autism spectrum disorders (ASDs); however, the neurochemical backgrounds remain unclear. To elucidate neurochemical processes underlying aberrant brain growth in ASD, we conducted a comprehensive literature search and a meta-analysis of (1)H-magnetic resonance spectroscopy ((1)H-MRS) studies in ASD. From the 22 articles identified as satisfying the criteria, means and s.d. of measure of N-acetylaspartate (NAA), creatine, choline-containing compounds, myo-Inositol and glutamate+glutamine in frontal, temporal, parietal, amygdala-hippocampus complex, thalamus and cerebellum were extracted. Random effect model analyses showed significantly lower NAA levels in all the examined brain regions but cerebellum in ASD children compared with typically developed children (n=1295 at the maximum in frontal, P<0.05 Bonferroni-corrected), although there was no significant difference in metabolite levels in adulthood. Meta-regression analysis further revealed that the effect size of lower frontal NAA levels linearly declined with older mean age in ASD (n=844, P<0.05 Bonferroni-corrected). The significance of all frontal NAA findings was preserved after considering between-study heterogeneities (P<0.05 Bonferroni-corrected). This first meta-analysis of (1)H-MRS studies in ASD demonstrated robust developmental changes in the degree of abnormality in NAA levels, especially in frontal lobes of ASD. Previously reported larger-than-normal brain size in ASD children and the coincident lower-than-normal NAA levels suggest that early transient brain expansion in ASD is mainly caused by an increase in non-neuron tissues, such as glial cell proliferation.
Lien vers le texte intégral (Open Access ou abonnement)
4. Cashin A, Gallagher H, Newman C, Hughes M. {{Autism and the Cognitive Processing Triad: A Case for Revising the Criteria in the Diagnostic and Statistical Manual}}. {J Child Adolesc Psychiatr Nurs};2012 (Aug);25(3):141-148.
TOPIC: The next iteration of the Diagnostic and Statistical Manual of Mental Disorders is due for release in May 2013. The current diagnostic criteria for autism are based on a behavioral triad of impairment, which has been helpful for diagnosis and identifying the need for intervention, but is not useful with regard to developing interventions. Revised diagnostic criteria are needed to better inform research and therapeutic intervention. PURPOSE: This article examines the research underpinning the behavioral triad of impairment to consider alternative explanations and a more useful framing for diagnosis and intervention. SOURCES: Contemporary research and literature on autism were used in this study. CONCLUSIONS: It is proposed that the cognitive processing triad of impaired abstraction, impaired theory of mind, and impaired linguistic processing become the triad of impairment for autism in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. These are investigable at the diagnostic level and can usefully inform intervention. Further, in addressing the debate on whether restrictive and repetitive behavior should remain central to diagnosis or be replaced by a deficit in imagination, the authors argue that both behavioral manifestations are underpinned by impaired abstraction.
Lien vers le texte intégral (Open Access ou abonnement)
5. Davidovitch M, Hemo B, Manning-Courtney P, Fombonne E. {{Prevalence and Incidence of Autism Spectrum Disorder in an Israeli Population}}. {J Autism Dev Disord};2012 (Jul 27)
The prevalence of autism spectrum disorders has been steadily rising. In most parts of the world, rates as high as 1 % are reported, including in the United States. In Israel, previously reported prevalence rates have been in the 0.2 % range, and were based on parental reporting of diagnosis. In this study, records from one of the largest Israeli Health Maintenance organizations were used to calculate both incidence and prevalence of autism spectrum disorder (ASD) in Israel. Israeli prevalence of ASD was calculated at 0.48 % for 1-12 years olds and 0.65 % for 8 year old children in 2010, higher than previous Israeli reports, but still lower than prevalence estimates for the US. Incidence calculations ranged from 0.65 to 0.84 per 1,000 children for children 1-12 year olds. Reasons for these differences are suggested and discussed.
Lien vers le texte intégral (Open Access ou abonnement)
6. Doyle-Thomas KA, Kushki A, Duerden EG, Taylor MJ, Lerch JP, Soorya LV, Wang AT, Fan J, Anagnostou E. {{The Effect of Diagnosis, Age, and Symptom Severity on Cortical Surface Area in the Cingulate Cortex and Insula in Autism Spectrum Disorders}}. {J Child Neurol};2012 (Jul 25)
Functional activity in the anterior cingulate cortex and insula has been reported to be abnormal during social tasks in autism spectrum disorders. However, few studies have examined surface morphometry in these regions and how this may be related to autism spectrum disorder symptomatology. In this study, 27 individuals with autism spectrum disorders and 25 controls between the ages of 7 to 39 years underwent structural magnetic resonance imaging. Our primary analysis examined differences in surface area in the cingulate and insula, between individuals with and without autism spectrum disorders, as well as age-related changes and associations with social impairments. Surface area in the right cingulate was significantly different between groups and decreased more rapidly with age in autism spectrum disorder participants. In addition, greater surface area in the insula and isthmus was associated with poorer social behaviors. Results suggest atypical surface morphometry in brain regions involved in social function, which appeared to be related to poorer social ability scores.
Lien vers le texte intégral (Open Access ou abonnement)
7. Eriksson MA, Westerlund J, Hedvall A, Amark P, Gillberg C, Fernell E. {{Medical conditions affect the outcome of early intervention in preschool children with autism spectrum disorders}}. {Eur Child Adolesc Psychiatry};2012 (Jul 27)
The aim was to explore the frequency of genetic and other medical conditions, including epilepsy, in a population-based group of 208 preschool children with early diagnosis of Autism spectrum disorders (ASD) and to relate outcome at a 2-year follow-up to the co-existing medical findings. They had all received early intervention. The Vineland Adaptive Behaviour Scales (VABS-II) composite score served as the primary outcome measure. In the total group, 38/208 children (18 %) had a significant medical or genetic condition. Epilepsy was present in 6.3 % at the first assessment and in 8.6 % at follow-up and was associated with more severe intellectual impairment. A history of regression was reported in 22 %. Children with any medical/genetic condition, including epilepsy, as well as children with a history of regression had significantly lower VABS-II scores at the 2-year follow-up. Children with a medical/genetic condition, including epilepsy, had been diagnosed with ASD at an earlier age than those without such conditions, and early age at diagnosis also correlated negatively with adaptive functioning outcome. The results underscore the importance of considering medical/genetic aspects in all young children with ASD and the requirement to individualize and tailor interventions according to their specific needs.
Lien vers le texte intégral (Open Access ou abonnement)
8. Momeni N, Bergquist J, Brudin L, Behnia F, Sivberg B, Joghataei MT, Persson BL. {{A novel blood-based biomarker for detection of autism spectrum disorders}}. {Transl Psychiatry};2012 (Feb 21);2:e91.
Autism spectrum disorders (ASD) are classified as neurological developmental disorders. Several studies have been carried out to find a candidate biomarker linked to the development of these disorders, but up to date no reliable biomarker is available. Mass spectrometry techniques have been used for protein profiling of blood plasma of children with such disorders in order to identify proteins/peptides that may be used as biomarkers for detection of the disorders. Three differentially expressed peptides with mass-charge (m/z) values of 2020+/-1, 1864+/-1 and 1978+/-1 Da in the heparin plasma of children with ASD that were significantly changed as compared with the peptide pattern of the non-ASD control group are reported here. This novel set of biomarkers allows for a reliable blood-based diagnostic tool that may be used in diagnosis and potentially, in prognosis of ASD.
Lien vers le texte intégral (Open Access ou abonnement)
9. Robertson AE, Simmons DR. {{The Relationship between Sensory Sensitivity and Autistic Traits in the General Population}}. {J Autism Dev Disord};2012 (Jul 26)
Individuals with Autism Spectrum Disorders (ASDs) tend to have sensory processing difficulties (Baranek et al. in J Child Psychol Psychiatry 47:591-601, 2006). These difficulties include over- and under-responsiveness to sensory stimuli, and problems modulating sensory input (Ben-Sasson et al. in J Autism Dev Disorders 39:1-11, 2009). As those with ASD exist at the extreme end of a continuum of autistic traits that is also evident in the general population, we investigated the link between ASD and sensory sensitivity in the general population by administering two questionnaires online to 212 adult participants. Results showed a highly significant positive correlation (r = .775, p < .001) between number of autistic traits and the frequency of sensory processing problems. These data suggest a strong link between sensory processing and autistic traits in the general population, which in turn potentially implicates sensory processing problems in social interaction difficulties.
Lien vers le texte intégral (Open Access ou abonnement)
10. Wall DP, Kosmicki J, Deluca TF, Harstad E, Fusaro VA. {{Use of machine learning to shorten observation-based screening and diagnosis of autism}}. {Transl Psychiatry};2012 (Feb 21);2:e100.
The Autism Diagnostic Observation Schedule-Generic (ADOS) is one of the most widely used instruments for behavioral evaluation of autism spectrum disorders. It is composed of four modules, each tailored for a specific group of individuals based on their language and developmental level. On average, a module takes between 30 and 60 min to deliver. We used a series of machine-learning algorithms to study the complete set of scores from Module 1 of the ADOS available at the Autism Genetic Resource Exchange (AGRE) for 612 individuals with a classification of autism and 15 non-spectrum individuals from both AGRE and the Boston Autism Consortium (AC). Our analysis indicated that 8 of the 29 items contained in Module 1 of the ADOS were sufficient to classify autism with 100% accuracy. We further validated the accuracy of this eight-item classifier against complete sets of scores from two independent sources, a collection of 110 individuals with autism from AC and a collection of 336 individuals with autism from the Simons Foundation. In both cases, our classifier performed with nearly 100% sensitivity, correctly classifying all but two of the individuals from these two resources with a diagnosis of autism, and with 94% specificity on a collection of observed and simulated non-spectrum controls. The classifier contained several elements found in the ADOS algorithm, demonstrating high test validity, and also resulted in a quantitative score that measures classification confidence and extremeness of the phenotype. With incidence rates rising, the ability to classify autism effectively and quickly requires careful design of assessment and diagnostic tools. Given the brevity, accuracy and quantitative nature of the classifier, results from this study may prove valuable in the development of mobile tools for preliminary evaluation and clinical prioritization-in particular those focused on assessment of short home videos of children-that speed the pace of initial evaluation and broaden the reach to a significantly larger percentage of the population at risk.
