POS1284 PAINFUL CERVICAL INVOLVEMENT AND FEBRILE TORTICOLLIS: A FREQUENT SYMPTOM OF PIMS

Background

Pediatric Inflammatory Multisystemic Syndrome associated to SARS-CoV2 (PIMS) happens 4 to 6 weeks after SARS-CoV2 infection1-2. Its early diagnostic recognition as well as its early management is important to avoid cardiac complications related to this pathology.

Objectives

To highlight a frequent symptom in PIMS and improve its therapeutic care.

Methods

The JIR Cohort database, an international registry collecting data on patients with pediatric inflammatory diseases, was consulted to include patients between 03/15/20 and 12/31/2021.

Results

Of the 140 patients in whom a diagnosis of PIMS was retained, we present a series of 38 patients (27%) who presented at diagnosis or during evolution, febrile torticollis or painful cervical involvement. These patients were on average 8.2 years old (0.6-15.2). The proportion of boys was 14 out of 38 (37%). Twenty-four patients out of 33 (73%) were hospitalized in intensive care. Ten patients out of 38 (26%) underwent cervical imaging, 5 (50%) had abnormalities such as collection or infiltration of the soft tissues. At the therapeutic level, 27/38 patients (71%) received corticosteroid therapy, 33/38 (87%) immunoglobulins, and 26/38 (68%) antibiotic therapy.

Conclusion

PIMS is a pathology with significant clinical heterogeneity and severe consequences in case of delay in therapeutic management. In this epidemic context, it is important to consider PIMS in any patient with febrile torticollis, especially if he does not respond to antibiotics.

References

[1]Feldstein LR, Rose EB, Horwitz SM, Collins JP, Newhams MM, Son MBF, et al. Multisystem Inflammatory Syndrome in U.S. Children and Adolescents. N Engl J Med. 23 juill 2020.

[2]Whittaker E, Bamford A, Kenny J, Kaforou M, Jones CE, Shah P, et al. Clinical Characteristics of 58 Children With a Pediatric Inflammatory Multisystem Syndrome Temporally Associated With SARS-CoV-2. JAMA. 8 juin 2020

Disclosure of Interests

None declared

Prognostic value of diffusion-weighted magnetic resonance imaging of brain in fetal growth restriction: results of prospective multicenter study

OBJECTIVE

To measure prospectively apparent diffusion coefficient (ADC) values between 28 and 32 weeks of gestation in different cerebral territories of fetuses with estimated fetal weight (EFW) ≤ 5^th centile, and analyze their association with adverse perinatal outcome.

METHODS

This was a prospective study involving six tertiary-level perinatal centers. In the period 22 November 2016 to 11 September 2017, we included singleton, small-for-gestational-age (SGA) fetuses with EFW ≤ 5^th percentile, between 28 and 32 weeks of gestation, regardless of the umbilical artery Doppler and maternal uterine artery Doppler findings. A fetal magnetic resonance imaging (MRI) examination with diffusion-weighted sequences (DWI) was performed within 14 days following inclusion and before 32 weeks. ADC values were calculated in the frontal and occipital white matter, basal ganglia and cerebellar hemispheres. An ultrasound examination was performed within 1 week prior to the MRI examination. The primary outcome was a composite measure of adverse perinatal outcome, defined as any of the following: perinatal death; admission to neonatal intensive care unit with mechanical ventilation > 48 h; necrotizing enterocolitis; Grade III-IV intraventricular hemorrhage; periventricular leukomalacia. A univariate comparison of median ADC values in all cerebral territories between fetuses with and those without adverse perinatal outcome was performed. The association between ADC values and adverse perinatal outcome was then analyzed using multilevel logistic regression models to adjust for other common prognostic factors for growth-restricted fetuses.

RESULTS

MRI was performed in 64 patients, of whom five were excluded owing to fetal movement artifacts on DWI and two were excluded for termination of pregnancy with no link to fetal growth restriction (FGR). One intrauterine death occurred secondary to severe FGR. Among the 56 liveborn neonates, delivered at a mean ± SD gestational age of 33.6 ± 3.0 weeks, with a mean birth weight of 1441 ± 566 g, four neonatal deaths occurred. In addition, two neonates required prolonged mechanical ventilation, one of whom also developed necrotizing enterocolitis. Overall, therefore, seven out of 57 (12.3%) cases had an adverse perinatal outcome (95% CI, 3.8-20.8%). The ADC values in the frontal region were significantly lower in the group with adverse perinatal outcome vs those in the group with favorable outcome (mean values of both hemispheres, 1.68 vs 1.78 × 10^-3  mm² /s; P = 0.04). No significant difference in ADC values was observed between the two groups in any other cerebral territory. A cut-off value of 1.70 × 10^-3  mm² /s was associated with a sensitivity of 57% (95% CI, 18-90%), a specificity of 78% (95% CI, 63-88%), a positive predictive value of 27% (95% CI, 8-55%) and a negative predictive value of 93% (95% CI, 80-98%) for the prediction of adverse perinatal outcome. A mean frontal ADC value < 1.70 × 10^-3  mm² /s was not associated significantly with an increased risk of adverse perinatal outcome, either in the univariate analysis (P = 0.07), or when adjusting for gestational age at MRI and fetal sex (odds ratio (OR), 6.06 (95% CI, 0.9-37.1), P = 0.051) or for umbilical artery Doppler (OR, 6.08 (95% CI, 0.89-41.44)).

CONCLUSION

This first prospective, multicenter, cohort study using DWI in the setting of SGA found lower ADC values in the frontal white-matter territory in fetuses with, compared with those without, adverse perinatal outcome. To determine the prognostic value of these changes, further standardized evaluation of the neurodevelopment of children born with growth restriction is required. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

E.U. paediatric MOG consortium consensus: Part 1 - Classification of clinical phenotypes of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

Over the past few years, increasing interest in the role of autoantibodies against myelin oligodendrocyte glycoprotein (MOG-abs) as a new candidate biomarker in demyelinating central nervous system diseases has arisen. MOG-abs have now consistently been identified in a variety of demyelinating syndromes, with a predominance in paediatric patients. The clinical spectrum of these MOG-ab-associated disorders (MOGAD) is still expanding and differs between paediatric and adult patients. This first part of the Paediatric European Collaborative Consensus emphasises the diversity in clinical phenotypes associated with MOG-abs in paediatric patients and discusses these associated clinical phenotypes in detail. Typical MOGAD presentations consist of demyelinating syndromes, including acute disseminated encephalomyelitis (ADEM) in younger, and optic neuritis (ON) and/or transverse myelitis (TM) in older children. A proportion of patients experience a relapsing disease course, presenting as ADEM followed by one or multiple episode(s) of ON (ADEM-ON), multiphasic disseminated encephalomyelitis (MDEM), relapsing ON (RON) or relapsing neuromyelitis optica spectrum disorders (NMOSD)-like syndromes. More recently, the disease spectrum has been expanded with clinical and radiological phenotypes including encephalitis-like, leukodystrophy-like, and other non-classifiable presentations. This review concludes with recommendations following expert consensus on serologic testing for MOG-abs in paediatric patients, the presence of which has consequences for long-term monitoring, relapse risk, treatments, and for counselling of patient and families. Furthermore, we propose a clinical classification of paediatric MOGAD with clinical definitions and key features. These are operational and need to be tested, however essential for future paediatric MOGAD studies.

Craniosynostosis and metabolic bone disorder. A review

INTRODUCTION

Some metabolic bone disorders may result in the premature closure of one or more calvarial sutures during childhood, potentially leading to a cranioencephalic disproportion. The aim of this paper is to review the characteristics and consequences of craniosynostosis associated with metabolic disorder.

MATERIAL AND METHODS

A review of the literature on metabolic forms of craniosynostosis was performed.

RESULTS

The most common forms of craniosynostosis associated with metabolic bone disorder were isolated sagittal suture fusion with or without scaphocephaly, and sagittal suture fusion associated with coronal suture fusion (oxycephaly) or also with lambdoid suture fusion (pansynostosis). Synostosis may be well-tolerated, but in some subjects results in neurodevelopmental and functional impairment that is sometimes severe.

CONCLUSION

The impact of metabolic synostosis is very variable, depending on the specific underlying metabolic disease, with a large spectrum of morphological and functional consequences. Diagnosis should be early and management should be carried out by a multidisciplinary team with expertise in both rare skeletal disorders and craniosynostosis. The impact of emergent medical therapies recently developed for some of these diseases will be assessed by systematic coherent follow-up of international registries.

Imaging features of atypical bleeds in young patients with hemophilia

Hemarthroses and muscle bleeds are well-known and well-documented complications in pediatric and young adult hemophilia patients. In contrast, deep bleeds in atypical locations can be a diagnostic challenge, since clinicians and radiologists are often unfamiliar with their clinical and radiological features. Some atypical bleeds, however, can be life-threatening or severely disabling, highlighting the need for prompt, accurate diagnosis. Rare bleeds include central nervous system bleeds (including intracranial and spinal hematomas), urogenital bleeds, intra-abdominal bleeds (mesenteric and gastrointestinal wall hematomas) and pseudo tumors in unusual locations like the sinonasal cavities. Because clinical assessment can be difficult, clinicians and radiologists should be aware of the possibility of these rare complications in their hemophilia patients, so that they can avoid unnecessary invasive diagnostic and surgical procedures and institute prompt, appropriate treatment. The purpose of this review is to illustrate the imaging features of bleeds that occur in rare locations in young (i.e., children and young adults) patients with hemophilia to make the reader more familiar with these conditions.

[Value of whole-body MRI in vertebral fractures]

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare autoinflammatory disease in children. Pathological vertebral fracture may be the first symptom revealing this disease. We describe the case of a 14-year-old boy, with no significant past medical history, who had a sudden dorsal pain after carrying a friend on his back. Plain radiographs and MRI showed fractures of the superior endplate of T5 and T6 associated with a mild degree of kyphosis. MRI allowed ruling out discitis. The diagnostic hypotheses raised were cancer (lymphoma, leukemia), Langerhans cell histiocytosis, osteogenesis imperfecta, and CRMO. A whole-body MRI (wbMRI) was performed and disclosed several clinically silent signal abnormalities in key sites of CRMO (pelvic bone and tibial metaphyses). We point out that CRMO should be systematically added to the list of possible diseases in case of vertebral fracture. In this perspective, wbMRI is a major noninvasive tool to assess the diagnosis of CRMO, and allows avoiding a bone biopsy in most cases.

Ovarian tumors in children and adolescents: a series of 41 cases

OBJECTIVE

Pictorial review with a detailed semiological analysis of ovarian tumors in children and adolescents to provide a relevant diagnostic approach.

PATIENTS AND METHODS

Retrospective study (2001-2011) of 41 patients under the age of 15 who underwent surgery for an ovarian mass with a definite pathological diagnosis.

RESULTS

Sixty-two percent of the lesions were benign, 33% were malignant and 5% were borderline. Germ cell tumors were most frequent (77.5%), followed by sex cord stromal tumors (12.5%) and epithelial tumors (7.5%). Malignant tumors were more frequent in children between 0 and 2 years old. On imaging, calcifications and fat were specific for germ cell tumors; the presence of a mural nodule was predictive of a mature teratoma (P<0.001). Predictive factors for malignancy were clinical, including abdominal distension (P<0.01) or a palpable mass (P=0.05), biological, including increased hCG and/or AFP levels (P<0.001) and radiological, including tumors larger than 12 cm (P<0.05), tumoral hypervascularity (P<0.01) and voluminous ascites (P<0.01).

CONCLUSION

This semiological analysis confirms the role of imaging in diagnosing the etiology of ovarian lesions in children and adolescents and emphasizes the importance identifying tumoral hypervascularity, which, in addition to classic criteria, is highly predictive of malignancy.

Flatfoot in children and adolescents. Analysis of imaging findings and therapeutic implications

INTRODUCTION

Pes planovalgus (PPV) is a complex three-dimensional deformity of which routine radiographs provide only a two-dimensional analysis.

HYPOTHESIS

Angles and other radiographic parameters of the foot in children and adolescents, when studied on both the dorsoplantar and the lateral view, can be used to establish a radiographic classification system for PPV that provides useful therapeutic guidance in clinical practice.

MATERIALS AND METHODS

A retrospective single-centre study was conducted on 65 feet in 35 patients aged 7 to 18 years and having adequate ossification. All patients had a clinical diagnosis of idiopathic or neurologic PPV and available weight-bearing dorsoplantar and strict lateral radiographs. We excluded pes planus due to tarsal coalition, congenital bone deformities, or overcorrection of talipes equinovarus (n=25). All possible axes were drawn and angles measured after an evaluation of interindividual agreement.

RESULTS

We identified four patterns of PPV: subtalar pes planus (n=16) with marked subtalar valgus and longitudinal sag predominating at the talonavicular joint, midtarsal pes planus (n=12) without subtalar valgus but with marked midtarsal abduction and sag predominating at the cuneonavicular joint, mixed pes planus (n=28) with subtalar valgus, midtarsal abduction, and sag at both the talonavicular and cuneonavicular joints, and pes planocavus (n=9) with sag of the medial arch and cavus deformity of the lateral arch.

CONCLUSION

This original classification system provides therapeutic guidance by helping to match the surgical procedure to the nature and location of the deformities.

LEVEL OF EVIDENCE

Level IV.

[Shaken baby syndrome: which lesions in imaging ?]

Non-accidental brain trauma (also called shaken baby syndrome) represent the main cause for morbidity and mortality in the context of child abuse. It often occur in young infants aged less than 8months. The shaking leading to brain injuries are very violent and sometimes associated with a final impact. Intracranial injuries may be isolated without skeletal trauma or bruising. In any suspicion of such a diagnosis, emergency hospitalization is indicated. Brain CT, easy to perform in emergency, is the diagnostic key. It discloses diffuse subdural hematomas in typical sites as vertex, interhemispheric space and tentorium. There is no clear background of trauma and the related story is changing over time. The 3D analysis of the skull looks for signs of recent impact as a fracture that is sometimes complex and/or a soft tissue swelling of the scalp. Intraparenchymal injuries (contusions, tearing, and overall anoxic ischemic injuries) are better analyzed with MRI. The prognosis depends on their extent. Ophtalmologic examination is systematically performed looking for retinal hemorrhages (around one third of cases) which may be very subtle. Bruising is a major diagnostic sign, but inconstantly present. A precise datation of skeletal and/or brain injuries is not possible with imaging and the only indication of use is to establish the presence of "age different lesions". This indicates repeated trauma and thereby a high risk of recurrence.

Toward a better understanding of brain lesions during metachromatic leukodystrophy evolution

BACKGROUND AND PURPOSE

The prospect of new therapies in MLD stresses the need to refine the indications for treatment. The aim of this study was, therefore, to perform a detailed analysis of MRI brain lesions at diagnosis and follow-up, to better understand the natural history of MLD.

MATERIAL AND METHODS

This retrospective case-control study (2005-2010) looked at 13 patients with MLD (2-5 years of age) with 28 MRIs (mean follow-up, 2 years), compared with 39 age- and sex-matched controls. All MRIs were evaluated qualitatively and semiquantitatively. The Student t test, Wilcoxon signed rank test, and Pearson correlation were used for statistical analysis (P < .05).

RESULTS

In addition to diffuse symmetric supratentorial WM T2 hyperintensities with a tigroid pattern (70%) and T2 hyperintensities in the CC (100%) and internal capsules (46%), we found significant GM abnormalities such as thalamic T2 hypointensity (92%), thalamic (23%, P < .05, EJ) and caudate nuclei (23%, P < .05, EJ) atrophy, and cerebellar atrophy without WM involvement (15%). The pattern of splenium involvement progression was misleading, with initially diffuse high signal intensity, which later became curvilinear before finally progressing to atrophy (23%, P < .05; EJ). This should not be mistaken for a disease regression. Spectroscopy confirmed a decrease in the NAA/Cr ratio, an increase in the Cho/Cr ratio and in myo-inositol, and a lactate resonance.

CONCLUSIONS

Thalamic changes may be a common finding in MLD, raising the prospect of primary GM lesions. This may prove important when evaluating the efficacy of new treatments.

Pineal cysts in children

OBJECTIVE: To describe the prevalence and characteristics of pineal cysts found on MRI in children. METHODS: This is a retrospective monocentric study of all brain magnetic resonance imaging (MRI) examinations performed under the same technical conditions for checking the idiopathic nature of short stature (ISS group, n = 116) and for the investigation of central precocious puberty (CPP) over a 3-year period (n = 56). Dimensions, wall and septal thickness, number of locules, signal intensity, and the presence of a solid component were analysed. Ten of 19 cysts were re-evaluated (follow-up interval 4-28 months). The prevalence of the pineal cysts was compared between the two groups using χ2 and Fisher's exact tests, and a significance threshold of p < 0.05. RESULTS: The prevalence of cysts was comparable in the two groups, CPP (10.7%) and ISS (11.2%). Cyst characteristics were similar in the two groups and 74% had thin septations. None of the cysts changed on follow-up. None of the children with pineal cysts exhibited neurological signs. CONCLUSION: Benign pineal cysts are a common finding in young children. High-resolution MRI demonstrates that these cysts are often septated. This pattern is a normal variant and does not require follow-up MR imaging or IV contrast media.

Fetal tumors of the choroid plexus: is differential diagnosis between papilloma and carcinoma possible?

Fetal choroid plexus tumors are uncommon. The prognosis is widely variable and depends on the histological findings: papilloma or carcinoma. We report a case of prenatal diagnosis of choroid plexus mass detected by ultrasound at 33 weeks of gestation. Prenatal (T1, T2, T2* and diffusion weighted sequences) magnetic resonance imaging (MRI) was used to rule out a hematoma. Follow-up examination by ultrasound and MRI revealed a significant increase in the volume of the mass, suggesting a diagnosis of malignant tumor. A healthy neonate was delivered by Cesarean section at 38 weeks of gestation. Full surgical excision of the tumor was performed at 20 days after delivery and histological analysis revealed a papilloma.

Pediatric outcome of children with the prenatal diagnosis of isolated septal agenesis

BACKGROUND

Isolated Septal Agenesis (SA) is a rare disease with clinical outcomes (especially neurological outcomes) that are unknown. The purpose of this study was to evaluate the clinical outcome of these children.

METHODS

We conducted a retrospective multicenter study of 17 children with an isolated SA or SA combined with a moderate ventricular dilatation (VD) that was diagnosed antenatally and confirmed by a magnetic resonance imaging (MRI) performed in the antenatal period.

RESULTS

Of the 17 children, 14 had normal neurological examinations, 2 had language development delay and visuo-spatial dyspraxia, and 3 of the 17 children had behavioral problems. Eight children had neuropsychological evaluations, and the results were normal in six cases. There were 3 cases of septo-optic dysplasia (SOD) diagnosed postnatally, which highlighted the difficulties in assessing the optic tract and hypothalamic-pituitary region in antenatal imaging. Language delay and behavioral disorders were the main abnormalities at follow-up.

CONCLUSION

The discovery of an isolated SA reveals the difficulties of prenatal diagnosis to correlate the neurological and functional prognosis to morphological findings. The prognosis seemed to be good. It appears necessary to improve the diagnostic performance of fetal brain imaging and to follow-up these children prospectively to assess their long-term cognitive-behavioral outcomes.

Feasibility of dynamic MRI for evaluating velopharyngeal insufficiency in children

OBJECTIVE

To demonstrate the feasibility of dynamic MRI with near-real-time temporal resolution for analysing velopharyngeal closure.

METHODS

Eleven children and young adults (seven girls, four boys, mean age: 8.4 years) with suspected velopharyngeal insufficiency (VPI), and one healthy volunteer underwent MRI (1.5 Tesla) using T2 fast imaging sequences. Imaging was done without any sedation at rest and during various phonations in the axial and sagittal planes. Images were analysed by two radiologists, a plastic surgeon and a speech therapist.

RESULTS

The MRI examinations were well tolerated by even the youngest patient. A qualitative analysis found that the sagittal dynamic sequences during phonation were in relation to the clinical data in all patients. A quantitative analysis enabled calculation of the elevation angle of the soft palate in relation to the hard palate, the velar eminence angle and the percentage of reduction of the antero-posterior diameter of the pharyngeal lumen.

CONCLUSION

Dynamic MRI is a non-invasive, rapid and repeatable method. It can be considered a complementary tool to endoscopy and fluoroscopy, particularly in children, for assessing VPI without any sedation or radiation exposure.

[Prenatal detection of brain anomalies with ultrasonography]

Ultrasound is the first-line imaging study of the fetal brain performed at 12, 22 and 32 weeks of gestation. The very structured evaluation of biometric and morphological data, facilitated by the use of a checklist, ensures a high quality examination. All patients where an anomaly of any key element is suspected should be referred to a center dedicated to prenatal diagnosis for confirmation irrespective of the gestational age. Prenatal diagnosis plays a significant role in France since medical interruption of pregnancy until term is authorized.

[Diffusion-weighted MR imaging of the normal fetal brain: marker of fetal brain maturation]

PURPOSE

To determine the reliability and variations of apparent diffusion coefficient (ADC) values in normal fetuses. Materials and methods. Retrospective study (2007-2008) on 22 normal fetal MR examinations, performed between 30 and 34 of gestation, using a routine protocol (T1W and T2W images in 3 planes, b=1,000 diffusion-weighted imaging) without sedation. ADC values were measured by placing 3 adjacent regions of interest (ROI) including a centrally located ROI over the right frontal and occipital white matter (6 ROI).

STATISTICAL ANALYSIS

reproducibility of adjacent ADC values (intraclass correlation coefficient: ICC) and comparison between frontal and occipital ADC values (Wilcoxon).

RESULTS

The mean ADC value was 1.78 mm(2)/s for the frontal white matter (+ or - 0.10) and 1.66 mm(2)/s for the occipital white matter (+ or - 0.12) with excellent reproducibility (ICC=0.91 in the frontal lobe) and good reproducibility for adjacent measurements (ICC=0.7). A linear inverse correlation existed between ADC values and gestational age in the occipital lobes, and a significant fronto-occipital gradient existed after 32 weeks of gestational age.

CONCLUSION

ADC value measurements are reliable and inversely correlated with gestational age due to fetal brain maturation. The existence of a fronto-occipital gradient after 32 weeks of gestational age could be a marker of normal maturation used in clinical practice.

[Current events in fetal magnetic resonance]

The challenge of fetal imaging is crucial in France because of the law allowing termination of pregnancy (TOP) until the end of pregnancy. Fetal MRI is an imaging tool always used after ultrasonography (US). Its indications are pertinent only in relation with a prenatal center. Fetal MRI raises parental anxiety to take into account before and during the examination. To date, cerebral indications are predominant. Fetal brain maturation can be followed with MRI (gyration and myelination) but the optimal moment of a fetal MRI depends on the suspected pathology: the analysis of gyration is possible only by 28 WG, as before this time, the brain surface is smooth; in contrast, the posterior fossa demonstrates a definitive morphology since 20 WG. The ventriculomegaly is the most frequent call sign and includes various entities. MRI can disclose associated abnormalities (heterotopia, gyration, white matter, median line), which can suggest diagnosis and pronosis. A cystic pouch of the posterior fossa must lead to a careful analysis of cerebellum and brainstem to approach the diagnosis. Extracerebral indications become progressively larger and fetal MRI is a useful complementary tool after US to study tumors, particularly cervicothoracic masses. MRI can help to assess the level of bowel obstruction but multiple stenosis and post-stenotic bowel is difficult to evaluate. Fetal MRI can help to evaluate bilateral important pyelocalicial dilatation.

[Venous infarction of the neonate]

PURPOSE

To determine the imaging features of hemorrhagic infarction in neonates.

PATIENTS AND METHODS

Retrospective study (1998-2008) of 19 children (17 premature and 2 term deliveries) with early lobar hyperechogenicity on transfontanel US (TFUS). Group I: 11 born infants with clinical as well as TFUS and MRI follow-up. Group II: 8 premature infants deceased within a week from multisystem pathology, with neuropathological study available in 3 cases.

RESULTS

Group I (n=11): periventricular hyperechogenicity in a frontal (7), frontoparietal (2), parietooccipital (1) and temporoparietal (1) distribution with developing cavitary change (n=6). MRI showed a cortex sparing intraparenchymal hematoma. Group II (n=8): periventricular hyperechogenicity in a frontal (4), frontoparietal or parietal (3) and occipital (1) with developing cavitary change (3). Neuropathological examination showed characteristic lesions of venous hemorrhagic infarction. Clinical outcome was generally favorable for the surviving infants with contralateral motor deficit (n=5) non-correlated to the extent of the initial lesions.

CONCLUSION

Venous hemorrhagic infarction mainly affetcs premature infants and typically involves the periventricular frontal white matter. Prognosis is generally favorable. It is thus important to differentiate this entity from asymmetrical cystic periventricular leukomalacia with much different prognosis.

Cerebral biometry in fetal magnetic resonance imaging: new reference data

OBJECTIVES

To provide normal magnetic resonance imaging (MRI) reference biometric data of the fetal brain, to evaluate reproducibility and gender effect, to compare the two cerebral hemispheres and to compare MRI with ultrasonographic biometry, in a large cohort.

METHODS

Normal cerebral fetal MRI examinations were collected prospectively and several parameters were measured: the supratentorial space (bone and cerebral fronto-occipital and biparietal (BPD) diameters), the length of the corpus callosum (LCC), the surface area, height and anteroposterior diameter of the vermis, the transverse cerebellar diameter (TCD) and the anteroposterior diameter of the pons. We evaluated the interobserver reproducibility of measurements and the possible gender effect on measurements of bone BPD, TCD and LCC. We compared right and left hemispheres, right and left atria and ultrasound and MRI measurements.

RESULTS

The study included 589 fetuses, ranging from 26 to 40 weeks. Normal values (from 3(rd) to 97(th) percentile) are provided for each parameter. Interobserver agreement was excellent, with an intraclass correlation coefficient (ICC) > 0.75 for many parameters. The gender effect was evaluated in 372 cases and did not reveal any clinically meaningful difference. Comparison between the right and left cerebral hemispheres and between the right and left atria did not reveal any meaningful differences. Ultrasound and MRI measurements of BPD and TCD were compared in 94 cases and 48 cases, respectively, and the agreement was excellent (ICC = 0.85).

CONCLUSIONS

We present new reproducible reference charts for cerebral MRI biometry at 26-40 weeks' gestation, from a large cohort of fetuses.

Interest of the steady state free precession (SSFP) sequence for 3D modeling of the whole fetus

Fetal magnetic resonance imaging (MRI) has been gaining interest over the last two decades. Current fast MRI sequences provide imaging data of the whole uterus in less than 20 seconds, avoiding fetal motion related artifacts without any maternal or fetal sedation. MRI has proved to be a useful adjunct to echographic screening for prenatal diagnosis. However, MRI volumetric data is still mainly interpreted on 2D slices and 3D applications remain limited. In this paper, we discuss the qualities of the SSFP MRI sequences to provide adequate data for 3D segmentation and modeling of the fetus. Potential exploitations of 3D segmentation and derived anatomical models cover several domains: biometric and morphologic clinical studies, quantitative longitudinal studies of normal and abnormal fetus developments, direct visualization of the overall fetus body and simulations in different fields (surgery, radiation dosimetry,...).

Anomalies cérébrales subtiles de l’Adrénomyéloneuropathie

PURPOSE

To describe subtle brain abnormalities detected on MRI in adult patients with adrenomyeloneuropathy (AMN). Materials and methods. Retrospective evaluation of data acquired prospectively as part of a clinical trial (Riluzole) in 66 adult patients with AMN without obvious brain lesion on MR. All patients underwent brain MR including T1W, T2W, FLAIR and spectroscopy. After a review had been validated by three different reviewers, review of MR images was performed by consensus using a semi-quantitative scale.

RESULTS

Preliminary analysis of MR images confirmed the presence of signal abnormalities involving the corticospinal tracts in 36 patients (54.6%). Additional subtle abnormalities were also detected: white matter palor, mainly parieto-occipital in location, with patchy hyperintensity in 36 patients (54.6%), hyperintense pontocerebellar fibers on T2W and FLAIR in 25 patients (41.7%). The presence of elevated Cho/Cr and mI/Cr ratios, described in the literature, were confirmed.

CONCLUSION

This retrospective study allows the description of an AMN pattern on MRI in patients without white matter or callosal abnormalities.

[Diffusion-weighted imaging of the brain: normal patterns, traps and artifacts]

Owing to its rapid acquisition time and high sensitivity, diffusion-weighted imaging has turned into a routine sequence for brain imaging. This is the case not only for stroke, but also for various diseases such as abscesses or tumors. Being aware of the artifacts is important for optimal interpretation. After a brief review of the normal patterns, the most frequent artifacts, inherent to the echoplanar imaging technique, are described and we provide suggestions to avoid them. Most current traps are caused by T2-weighting of the diffusion images; the key for avoiding erroneous interpretation relies on the ADC map.