Hypothermia for neonatal hypoxic-ischemic encephalopathy: Retrospective descriptive study of features associated with poor outcome.

AIM: To investigate the clinical, laboratory, electrophysiological, and imaging features associated with death or neurological impairment at 1 year of age in term neonates with hypoxic-ischemic encephalopathy (HIE) treated by therapeutic hypothermia (TH). METHODS: This was a single-center retrospective and descriptive study conducted over a period of 2 years. We included consecutive term newborns with moderate or severe HIE who were treated by TH initiated within the sixth hour after birth and continued for 72 h,. For all patients, brain magnetic resonance imaging (MRI) was performed before the eighth day and a score was established; furthermore, at least two electroencephalograms were recorded. RESULTS: Among the 33 patients included, 20 neonates had a favorable outcome and 13 had an unfavorable outcome. Early clinical seizures (15% vs. 53.8%, p = 0.047), the persistence of a poor prognosis according to the electroencephalogram pattern after TH (0% vs. 69.2%, p = 0.0001), and an elevated score on the early brain MRI (2 vs. 11, p < 0.001) combined with a high lactate/N-acetyl-aspartate ratio (0.52 vs. 1.33, p = 0.008) on spectroscopy were associated with death and a poor outcome. CONCLUSION: A combination of tools can help the medical team to establish the most reliable prognosis for these full-term neonates, to guide care, and to inform parents most appropriately and sincerely.

Severe Thoracic and Spinal Bone Abnormalities in neurofibromatosis type 1.

Neurofibromatosis type 1 (NF1) is an autosomal dominant, multi-system, neurocutaneous disorder that predisposes to the development of benign and malignant tumors. Classical skeletal abnormalities encompass sphenoid wing dysplasia, congenital bowing of the long bones and vertebral osteopathy associated with non-dystrophic or dystrophic scoliosis found in about 10% of NF1 patients. We report a 17-year-old boy affected by NF1 with extreme severe spinal and thoracic malformations affecting bone and lung tissues, including hypoplasia of the right lung, unilateral costal agenesis and severe dystrophic scoliosis characterized by association of hemivertebra, fusion of adjacent vertebral bodies and defective pedicles. At birth, he presented an acute respiratory distress requiring invasive ventilator support. The diagnosis of NF1 was confirmed at age 5 by the identification of a de novo heterozygous mutation c.4537C > T, p.Arg1513* in NF1. Trio-based Whole Exome Sequencing (WES) was performed to exclude coexistence of a second hit but no clearly other pathogenic variant has been identified. Until now, only one similar NF1 patient suffering from the same association of severe scoliosis and chest deformity leading to respiratory insufficiency was described. The severe prenatal NF1-related scoliosis could explain the lung abnormal development by absence of mechanical constraints. Severe Thoracic and Spinal Bone Abnormalities may be part of the NF1 bone phenotype and should be taken into account to allow adequate genetic counseling.

Analysis of the French national evaluation of radiology residents.

PURPOSE: In France, a national evaluation is given annually to radiology residents. The aim of this study was to perform both a docimological analysis of the quality of the questionnaire and a statistical analysis of the results. MATERIALS AND METHODS: This retrospective study, which included French radiology residents from Year 1 to Year 5 of residency, was performed from 2015 to 2017 across 25 medical universities in France. Both qualitative and quantitative docimological analyses were performed as assessed by the Cronbach alpha coefficient, the difficulty of question (PDI), and the coefficient of discrimination (Rir). Results to the questionnaire were compared between years of residency. RESULTS: The results of the analysis confirmed the quality of the questionnaire (Cronbach alpha coefficient=0.71, mean [PDI=0.40]) though the majority of questions could be answered by memory rather than cognitive ability. The mean Rir was 0.02, indicating that students could not be certified using only the questionnaire. The results measuring resident level of knowledge were moderate, with mean results ranging from 9.2/20 at the first year to 11.3/20 at the fifth year of residency (P<0.001). There were no significant differences in results obtained between the third, fourth, and fifth year of residency but results were significantly different among university hospitals. CONCLUSION: Even if close interactions exist between learning and pedagogic environment, our results suggest that it may be useful to further develop an evaluation process in relation with pedagogic instructions in order to provide more optimal training.

Childhood CT scans and cancer risk: impact of predisposing factors for cancer on the risk estimates.

To investigate the role of cancer predisposing factors (PFs) on the associations between paediatric computed tomography (CT) scan exposures and subsequent risk of central nervous system (CNS) tumours and leukaemia. A cohort of children who underwent a CT scan in 2000-2010 in 23 French radiology departments was linked with the national childhood cancers registry and national vital status registry; information on PFs was retrieved through hospital discharge databases. In children without PF, hazard ratios of 1.07 (95% CI 0.99-1.10) for CNS tumours (15 cases) and 1.16 (95% CI 0.77-1.27) for leukaemia (12 cases) were estimated for each 10 mGy increment in CT x-rays organ doses. These estimates were similar to those obtained in the whole cohort. In children with PFs, no positive dose-risk association was observed, possibly related to earlier non-cancer mortality in this group. Our results suggest a modifying effect of PFs on CT-related cancer risks, but need to be confirmed by longer follow-up and other studies.

[New tools in cystic fibrosis]. / Nouvelles techniques d'évaluation dans la mucoviscidose.

The use of 3 novel tools available for the diagnosis and treatment in cystic fibrosis are described here. 1) The lung clearance index is a sensitive method which can detect functional impairment in the first months after birth. 2) Detailed morphological analyses of the lung can be performed with the new MRI sequences, without any contrast medium or risk of radiation. The analysis of functional MRI data (perfusion, diffusion, ventilation, inflammation) will be possible, and these data will be correlated to morphological data. The exploration of other organs such as the sinuses, liver and abdomen during the same examination represents another definite advantage. 3) Organoïds are a good example of personalized medicine. This tool explores CFTR function and treatment response in each of the 2000 or so known CFTR mutations. These tests are limited to specialized centers, mostly within a research context. However, their generalization after standardization is expected in the near future.

Radiography of scoliosis: Comparative dose levels and image quality between a dynamic flat-panel detector and a slot-scanning device (EOS system).

PURPOSE: To compare radiation dose and image quality between a slot-scanning system (SSS) and a dynamic flat-panel detector (DFD) in assessing scoliosis in children. METHODS: An experimental study was first performed with a phantom to assess the quality of each device. The clinical part included a prospective observational dosimetric and qualitative comparative study with acquisition of whole-spine X-ray: SSS (31 children), DFD (26 children). Institutional review board approval and informed consent were obtained. Dosimetric statistical analysis was performed from dose area product (DAP) and entrance skin dose measured by thermo-luminescent dosimeters localized in the cervical, thoracic and sacral areas. Assessment of the diagnostic quality (phantom and clinical) was realized by independent evaluation by 3 observers, using statistical analysis of quality score and inter-observer reproducibility. RESULTS: DAP was equivalent with the 2 systems. Entrance skin dose was significantly higher with DFD in thoracic and pelvic regions (P<0.05). Image quality scores of the SSS were significantly better than DFD for a majority of criteria, in both phantom and clinical evaluations. CONCLUSION: For scoliosis evaluation, the SSS, compared to the DFD system, offers enhanced image quality while reducing the entrance skin dose in the most radiosensitive areas.

Are the studies on cancer risk from CT scans biased by indication? Elements of answer from a large-scale cohort study in France.

BACKGROUND: Recent epidemiological results suggested an increase of cancer risk after receiving computed tomography (CT) scans in childhood or adolescence. Their interpretation is questioned due to the lack of information about the reasons for examination. Our objective was to estimate the cancer risk related to childhood CT scans, and examine how cancer-predisposing factors (PFs) affect assessment of the radiation-related risk. METHODS: The cohort included 67,274 children who had a first scan before the age of 10 years from 2000 to 2010 in 23 French departments. Cumulative X-rays doses were estimated from radiology protocols. Cancer incidence was retrieved through the national registry of childhood cancers; PF from discharge diagnoses. RESULTS: During a mean follow-up of 4 years, 27 cases of tumours of the central nervous system, 25 of leukaemia and 21 of lymphoma were diagnosed; 32% of them among children with PF. Specific patterns of CT exposures were observed according to PFs. Adjustment for PF reduced the excess risk estimates related to cumulative doses from CT scans. No significant excess risk was observed in relation to CT exposures. CONCLUSIONS: This study suggests that the indication for examinations, whether suspected cancer or PF management, should be considered to avoid overestimation of the cancer risks associated with CT scans.

Radiation exposure from CT in early childhood: a French large-scale multicentre study.

OBJECTIVES: The increasing use of CT scans in the paediatric population raises the question of a possible health impact of ionising radiation exposure associated with CT scans. The aim of this study was to describe the pattern of CT use in early childhood. METHODS: In 14 major French paediatric radiology departments, children undergoing at least 1 CT scan before age 5, between 2000 and 2006, were included. For each examination, absorbed organ doses were calculated. RESULTS: 43% of the 27 362 children in the cohort were aged less than 1 year during their first exposure, with 9% being aged less than 1 month. The mean number of examinations per child was 1.6 (range 1-43). The examinations included: head in 63% of the cases, chest in 21%, abdomen and pelvis in 8% and others in 8%. Brain and eye lenses received the highest cumulative doses from head examinations, with mean organ dose values of 22 mGy (maximum 1107 mGy) and 26 mGy (maximum 1392 mGy), respectively. The mean cumulative effective dose was 3.2 mSv (range 0.1-189 mSv). CONCLUSION: CT scan exposure in childhood is responsible for relatively high doses to radiosensitive organs. The rather large dose range according to the protocols used requires their optimisation. The cohort follow-up will study the risk of long-term radiation-induced cancer.

[Typical patient radiation doses in diagnostic imaging]. / Ordre de grandeur des doses délivrées en radiodiagnostic.

Radiologists should be able to appreciate the radiation dose delivered to patients for routine diagnostic procedures. The radiology report should include data necessary to calculate the patient dose in Gray. Using the effective dose, it is possible to compare with other source of radiation exposure. Simple formulas, taking into account different anatomical regions, derived from dose-area product (conventional radiography) or dose-length product (CT) are provided to calculate the effective dose in Sievert. For conventional (non-interventional) radiography, the effective dose for a given exam is inferior or equal to the yearly background radiation. For CT, the effective dose corresponds to 1 to 10 years of yearly background radiation.

Efficiency of fractional anisotropy and apparent diffusion coefficient on diffusion tensor imaging in prognosis of neonates with hypoxic-ischemic encephalopathy: a methodologic prospective pilot study.

BACKGROUND AND PURPOSE: The DTI parameters (FA and ADC) reflect the properties of the brain microstructure. Decreased anisotropy is a common feature of cerebral tissue abnormalities. Our study investigates the neurologic prognostic efficiency of these parameters in white (PLIC, CP) and gray matter (PP) in the first days of life in term neonates with HIE. We hypothesize that lesions in related brain areas could be part of a physiopathologic substratum supporting neurologic deficiencies in this population. MATERIALS AND METHODS: A total of 22 neonates (13 girls and 9 boys; mean gestational age, 40 weeks +/- 9 days; birth weight, 3203 +/- 584 g) underwent brain MR imaging between day 1 and day 6 after birth; 6-noncollinear direction DTI was performed. FA and ADC were measured on specific brain areas. Amiel-Tison score was performed on day 8.5 +/- 4 (group A, favorable outcome [n = 16]; group B, unfavorable outcome [n = 6]). RESULTS: Intraobserver and interobserver comparison in DTI parameter measurements showed a coefficient of variability of less than 5%. In PLIC and PP, the ADC values were lower in group B compared with group A (P = .000027), whereas in PLIC and CP, the FA values were lower in group B compared with group A (P < .02). CONCLUSIONS: These findings indicate that a poor early neurologic outcome in neonates with HIE is associated with lower FA or ADC values in specific areas of white or gray matter. The difference in ADC/FA changes in the different brain areas explored may support possibly different pathologic processes.

[Prognostic value of MR in term neonates with neonatal hypoxic-ischemic encephalopath: MRI score and spectroscopy. About 26 cases]. / Apport pronostique de la résonance magnétique cérébrale dans l'encéphalopathie hypoxique-ischémique du nouveau-né à terme: score d'imagerie, spectroscopie. Etude de 26 cas.

UNLABELLED: Neonatal hypoxic-ischemic encephalopathy remains a major cause of chronic disability in childhood. Early diagnosis and prognosis are necessary for the clinician to adapt the treatment. However, there is yet no reliable test to predict the patient's evolution. OBJECTIVE: The aim of our study was to evaluate the predictive value of a personal magnetic resonance imaging (MRI) scoring system and of magnetic resonance spectroscopy (MRS). MATERIAL AND METHODS: We included 26 term newborns in condition of neonatal brain suffering. MR examination was performed during the first week of life for all patients and MRI and MRS data were collected. Standardised follow-up visits were made for all patients. Finally, prognostic value of the different criteria was evaluated with statistical tests. RESULTS: Our MRI scoring system proved to be linked to prognosis. A high MRI score, abnormal signal in the internal capsule, white matter or basal ganglia abnormalities with diffusion imaging were associated with unfavourable outcome. These results confirmed the data of the literature concerning the MRI predictive value. Our study also confirmed prognostic interest of MR: particularly, ratios using lactate were significantly linked to prognosis in our study. Specificity of the elevation of these ratios was interesting but sensibility was less optimal. CONCLUSION: We suggest using our MRI scoring system which associates standard MRI and diffusion imaging, which is significantly related to outcome. We confirm the prognostic value of MRS in this pathological situation. MR with diffusion sequence and spectroscopy, performed three to four days after birth appears to be an essential tool to manage these patients.

[Neonatal infections of the bones and joints]. / Infections ostéoarticulaires du nouveau-né

Neonatal osteoarticular infections remain rare, with an estimated incidence of 1 to 3 cases per 1000 admissions to Neonatal Intensive Care Units. It usually results from bacteraemia and may thus be induced by IV catheters. More rarely it is due to direct inoculation secondary to cutaneous damage, or extension of soft tissue infection. The particularity of bone vascularization in the newborn explains the frequency of abscess formation in the periosteum or in soft tissues. The main pathogen involved is S. aureus (3/4 of cases), followed by group B streptococci and enterobacteriacae. Infection consists mainly of localised and slowly progressing abscesses. However, multifocal and severe infection is possible, in particular when caused by an IV catheter. Ultrasonography is the best initial investigation, possibly leading to surgical care. Medical treatment must include 2 synergistic antistaphyloccocal antibiotics, possibly associated with cefotaxime. The outcome is generally favorable, but orthopaedic consequences may emerge if the growth plate is involved. Rare specific causes, such as syphilis or tuberculosis, should also be evoked, but the clinical context is generally helpful for the diagnosis.

Bardet-biedl syndrome and brain abnormalities.

Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disorder with clinical and genetic heterogeneity. The main features are obesity, polydactyly, pigmentary retinopathy, learning disabilities, hypogonadism, and renal abnormalities. To date, eleven genes have been cloned but there is still little knowledge about genotype/phenotype correlations. We describe three additional cases with BBS and cerebral abnormalities and focus on cerebellar abnormalities in BBS.

[Evaluation of the risk of overheating and displacement of orthodontic devices in magnetic resonance imaging]. / Evaluation des risques d'échauffement et de déplacement des appareils orthodontiques en imagerie par résonance magnétique.

The use of magnetic resonance imaging (MRI) in the exploration of the orofacial region of patients who have orthodontic appliances can be disturbed by artifacts, with a theoretical risk of displacement and overheating of the different materials used in odontology. The purpose of this study was to evaluate the thermal effects and the risk of displacement induced by MRI on certain metallic devices used in orthodontics. The results show a very moderate increase in temperature of the materials during MRI exposure, less than 1 degrees C, in particular in the metal wire linking the brackets. The maximal forces observed were on the order of 0.27 N. The risk of detachment and displacement seems to be nonexistent at 1.5 Tesla when the usual recommendations are respected. Temporary removal of the wire and verification of the adhesive is recommended. However, priority should be given to nonmagnetic or slightly magnetic material to limit artifacts as much as possible when exploring the head region.