Well though-out introduction of percutaneous Achilles tenotomy during functional treatment of congenital talipes equinovarus: Which indications produce the best results?

INTRODUCTION: Percutaneous Achilles tenotomy (PAT) was recently added to functional treatment of congenital talipes equinovarus (aka clubfoot). The aim of this study was to determine the relevance of a carefully chosen radiological criterion for the PAT indication and to evaluate its results. HYPOTHESIS: When the tibiocalcaneal angle (aTiCa) is larger than 75° at 4 months, doing PAT will improve the results of the functional method in the medium term and will reduce the surgery rate. PATIENTS AND METHODS: This prospective study involved 101 patients (151 feet) born between 2011 and 2014 with clubfoot who were treated with the French functional method and had at least 4 years' follow-up. The initial severity of the deformity was evaluated using the Diméglio scoring system. In our sample, 30 feet had a Diméglio rating of II (20%), 61 had a Diméglio rating of III (40%) and 60 feet had a Diméglio rating of IV (40%). The indication for PAT was made at 4 months of age when the aTiCa on a lateral radiograph of the foot in maximum correction was greater than 75°. The mean follow-up was 5 years. The final assessment was done using the modified Ghanem and Seringe classification. RESULTS: In the entire cohort, PAT was done in 113 feet (75%). None of the feet required a repeat PAT. Surgical release of the soft tissues was done in 20 feet (13%). None of the feet developed a rocker bottom deformity. Two feet were operated in the absence PAT (out of 38 in this subgroup) and 18 feet after PAT (out of 113 in this subgroup). The aTiCa angle did not vary in the PAT group based on whether surgical release was indicated afterwards or not. At the final assessment, 140 feet (93%) were classified as very good and 11 feet (7%) as good. DISCUSSION: The tibiocalcaneal angle is a relevant radiological criterion for the PAT indication in children with clubfoot. PAT has a positive impact on the outcomes. LEVEL OF EVIDENCE: II; prospective study.

Analysis of whole-body MRI artifacts in a pediatric population with a special emphasis on the effect of hands position.

PURPOSE: The purpose of this retrospective study was to determine the prevalence of artifacts on whole-body (WB) magnetic resonance imaging (MRI) examination in pediatric patients and identify their causes. MATERIALS AND METHODS: A total of 107 pediatric patients who underwent a total of 107 WB-MRI examinations, including short-tau inversion recovery (STIR) and T1-weighted sequences, were included. There were 62 girls and 45 boys with a mean age of 11 ± 3 (SD) years (age range: 2-16 years). WB-MRI examinations were analyzed for the presence of artifacts on STIR and T1-weighted sequences. Artifacts were further assigned to one of eight categories (motion, partial volume, cross-talk, phase sampling, susceptibility, equipment, noise, and "other") and 19 anatomical sites by a 4-year resident. Prevalence of artifacts were analyzed especially according to hands position during the examination for the upper limbs and patients' age. Age was expressed as a binary variable using median age (10 years) as the cut-off value. All qualitative variables were compared using chi-square test. RESULTS: A total of 3436 artifacts were found. The STIR sequences showed more "noise" artifacts (93/1038; 8.96%) and more "cross-talk" (102/1038; 9.83%) artifacts than T1-weighted sequences (12/1038 [1.16%] and 7/1038 [0.67%], respectively) (P < 0.001 for both). T1-weighted sequences showed more "equipment" (84/1038; 8.09%) and "stair-step" (a subset of "other") (41/1038; 3.95%) artifacts than the STIR sequences (39/1038 [3.76%] and 21/1038 [2.02%], respectively) (P < 0.001 and P = 0.01, respectively). T1-weighted sequences showed fewer artifacts on the wrists when the hands were under the bottom (P = 0.001). T1-weighted sequences showed less "equipment" artifacts when the hands were alongside the body (22/296; 7%) than on the abdomen (48/432; 11%) or under the bottom (14/128; 11%) (P < 0.001). STIR sequences showed more "motion" artifacts when the hands were on the abdomen (54/432; 13%) than alongside the body (30/296; 10%) or under the bottom (15/128; 12%) (P < 0.001). WB-MRI examinations had more "susceptibility" artifacts (38/960; 4%) and more "equipment" artifacts (81/960; 8.4%) in patients older than 10 years than in those under 10 years (23/752 [3.1%] and 42/752 [5.6%]) (P = 0.01 and P < 0.001, respectively). CONCLUSION: Artifacts on WB-MRI do not affect coronal STIR and T1-weighted sequences equally, so the use of both sequence types appears useful. Hands position should be considered with respect to both diagnostic benefit and safety.

Imaging patterns in pediatric hypophosphatasia.

Hypophosphatasia is a rare genetic disorder of calcium and phosphate metabolism due to ALPL gene mutations, which leads to abnormal mineralization of the bones and teeth. Hypophosphatasia is characterized by low serum alkaline phosphatase activity and a number of clinical signs, including failure to thrive, bone pain and dental issues. The diagnosis is suspected based on clinical, laboratory and imaging findings and confirmed by genetic testing. Diagnosis in children is often delayed due to a lack of disease awareness, despite specific imaging findings that are a cornerstone of the diagnosis. The recent approval of enzyme replacement therapy (bone-targeted recombinant tissue nonspecific alkaline phosphatase) has given imaging an important role in monitoring treatment efficacy. The aim of this pictorial essay is to review the imaging features of hypophosphatasia at diagnosis and during follow-up, including whole-body magnetic resonance imaging patterns.

Prevalence of Enthesopathies in Adults With X-linked Hypophosphatemia: Analysis of Risk Factors.

CONTEXT: Enthesopathies are the determinant of a poor quality of life in adults with X-linked hypophosphatemia (XLH). OBJECTIVE: To describe the prevalence of patients with enthesopathies and to identify the risk factors of having enthesopathies. METHODS: Retrospective study in the French Reference Center for Rare Diseases of the Calcium and Phosphate Metabolism between June 2011 and December 2020. Adult XLH patients with full body X-rays performed using the EOS® low-dose radiation system and clinical data collected from medical records. The main outcome measures were demographics, PHEX mutation, conventional treatment, and dental disease with the presence of enthesopathies. RESULTS: Of the 114 patients included (68% women, mean age 42.2 ± 14.3 years), PHEX mutation was found in 105 patients (94.6%), 86 (77.5%) had been treated during childhood. Enthesopathies (spine and/or pelvis) were present in 67% of the patients (n = 76). Patients with enthesopathies were significantly older (P = .001) and more frequently reported dental disease collected from medical records (P = .03). There was no correlation between the PHEX mutations and the presence of enthesopathies. Sixty-two patients had a radiographic dental examination in a reference center. Severe dental disease (number of missing teeth, number of teeth endodontically treated, alveolar bone loss, and proportion of patients with 5 abscesses or more) was significantly higher in patients with enthesopathies. CONCLUSION: Adult XLH patients have a high prevalence of enthesopathies in symptomatic adults patients with XLH seen in a reference center. Age and severe dental disease were significantly associated with the presence of enthesopathies.

Bone dysplasia.

Bone dysplasia is a large group that encompasses 436 rare diseases. Many of them are characterized by short stature or decreased growth velocity during puberty. The diagnosis of short stature due to skeletal dysplasia relies on (i) physical features such as disproportionate trunk/limbs, short limbs or extremities and/or stocky build, (ii) radiographic features to analyze mineralization, maturation and bone morphology, and (iii) whenever possible, the genetic characterization. Bone dysplasia mostly affect many organs, and therefore require multidisciplinary follow-up and care. The role of the pediatric endocrinologist is to assess the growth potential of these patients in coordination with the other caregivers, offer the best management of the growth to limit the psychosocial consequences of the extreme short stature and bone deformities.

Magnetic Resonance Imaging Features as Surrogate Markers of X-Linked Hypophosphatemic Rickets Activity.

OBJECTIVE: X-linked hypophosphatemic rickets (XLH) is the most common form of inheritable rickets. Rickets treatment is monitored by assessing alkaline phosphatase (ALP) levels, clinical features, and radiographs. Our objectives were to describe the magnetic resonance imaging (MRI) features of XLH and to assess correlations with disease activity. STUDY DESIGN: Twenty-seven XLH patients (median age 9.2 years) were included in this prospective single-center observational study. XLH activity was assessed using height, leg bowing, dental abscess history, and serum ALP levels. We looked for correlations between MRI features and markers of disease activity. RESULTS: On MRI, the median maximum width of the physis was 5.6 mm (range 4.8-7.8; normal <1.5), being >1.5 mm in all of the patients. The appearance of the zone of provisional calcification was abnormal on 21 MRI images (78%), Harris lines were present on 24 (89%), and bone marrow signal abnormalities were present on 16 (59%). ALP levels correlated with the maximum physeal widening and with the transverse extent of the widening. CONCLUSIONS: MRI of the knee provides precise rickets patterns that are correlated with ALP, an established biochemical marker of the disease, avoiding X-ray exposure and providing surrogate quantitative markers of disease activity.

[Which imaging in front of abdominal pain in children?]. / Quelle imagerie demander devant une douleur abdominale de l'enfant?

Imaging plays an important role in the diagnosis of abdominal pain. Plain abdomen radiography is of very limited value, but is still too often requested. Ultrasound is the first-line procedure. However, it does not always provide answers to all the questions. It is thus essential to know its limitations and flaws. Ultrasound should complement the physical examination.

How to explore and report children with suspected non-accidental trauma.

Child abuse is a controversial problem of special concern. Recent reports have focused on the broad variability of reporting to child protection services. Radiologists play a key role in the early diagnosis and imaging of suspected inflicted injury. Imaging must be performed and then interpreted with rigour.The aims of this review are: To review the recent recommended guidelines for imaging in cases of suspicion of abuse. These include a highly detailed complete skeletal survey with centered views, whilst brain CT and/or MRI are mandatory in children younger than 2 years. The use of abdominal imaging is debatable if the child has no symptoms. All siblings younger than 2 years should be assessed in the same way while the diagnosis of abuse is investigated. Body MRI is an interesting modality that remains a "work-in-progress". To highlight that dating of both brain and skeletal injuries is imprecise. The main point is, however, to determine if the pattern is of "age-different" lesions. This not only provides a strong argument for the diagnosis of abuse, but also indicates repetitive violence with a high risk for further injury and death. To remember that the medical perspective is to protect the child. Thus, radiologists must communicate clearly the suspicion of abuse and the degree of certainty to clinicians to aid reporting or hospitalization.

Giant dural venous sinus ectasia in neonates.

In this report, the authors describe 4 recent cases of posterior giant dural venous sinus ectasia in neonates diagnosed during pregnancy and encountered at 3 different institutions. Posterior giant venous sinus ectasia was diagnosed in 4 patients using antenatal ultrasonography and confirmed in 2 patients using prenatal MR imaging and in 3 patients using postnatal MR angiography. In 2 children angiography was performed at the age of 6 months. The pregnancy was terminated in 1 case, and the fetus underwent an autopsy. The 3 children who were born presented with various degree of cardiac insufficiency and were admitted to the intensive care unit after birth. Signs of increased intracranial pressure were present immediately after birth, including a bulging fontanel. No endovascular treatment was used in these cases. Surgery was performed in 2 cases as an attempt to alleviate increased intracranial pressure symptoms, without any real benefit. A slow venous flow in the ectasia was shown by ultrasonography in the case in which the pregnancy was terminated. Angiography or MR angiography did not show an obvious arteriovenous malformation in any of the cases, but an arteriovenous fistula secondary or contributing to the formation of the venous ectasia is one of the physiopathological hypotheses of the cause of this condition. Interestingly, spontaneous progressive thrombosis and regression of the intravascular component of the venous sinus ectasia was observed in all cases. The clinical outcome was acceptable in 1 child (who had a moderate handicap after the surgery) and good for the other 2 children (who had normal neurological development). Stratified thrombi of different ages are found in these giant venous ectasias and develop within the leaves of the dura close to the confluence of the major posterior venous sinuses. Therefore, it appears that the formation of a progressive thrombosis represents the normal evolution of these giant dural venous sinus ectasias, which explains the favorable outcome in some cases without specific surgical treatment, except for resuscitation techniques.

Impressive renal damage after acute pyelonephritis in a child.

Urinary tract infection (UTI) is one of the most common bacterial infections in children, and its role in the pathogenesis of scarred kidney is debated. We report on a 7-year-old child who presented with severe UTI. The early (day 4) renal computed tomography (CT) scan showed normal-sized kidneys (110 mm on the left, 105 mm on the right), whereas the control CT scan and dimercaptosuccinic acid (DMSA) scan, performed 1 and 2 months later, respectively, showed a small scarred right kidney (60 mm) with a 12% residual function. An intermittent right vesicoureteral reflux (VUR) was diagnosed by direct isotopic cystography and then treated by Cohen vesicoureteral reimplantation. The patient remained free of infectious recurrence, hypertension, or renal function decrease. This report demonstrates that one episode of acute pyelonephritis can lead to severe renal scarring. Whereas antenatal lesions are thought to have a stronger role in the causal pathway for reflux nephropathy than is UTI in addition to VUR, this observation reminds us that UTI can truly play an important role in damaging kidneys.

Dural sinus malformation (DSM) in fetuses. Diagnostic value of prenatal MRI and follow-up.

Dural sinus malformations (DSM) are rare malformations mainly reported after birth. The objectives of this study are to describe their prenatal patterns and to focus on their possible favorable outcome. This multicenter retrospective study reported 13 cases of DSM prenatally diagnosed. The admission criterion was a dural mass posterior to the vermis. In 12 patients, MRI was performed after US. Follow-up in 10 born babies (mean: 8 months) and three neuropathological examinations were available. In all fetuses, DSM presented as a well-delimited round mass involving the torcular. The follow-up examinations (n = 10) revealed progressive thrombosis of the DSM marked by a heterogeneous pattern (US and MRI) with concentric rings. The volume of the mass decreased, with complete regression in seven patients (five before and two after birth). One child died at the age of 5 months in the context of major hydrocephalus and another developed atrophy of the frontal lobes. The eight other babies were doing well (5 days to 3 years) without any treatment (n = 6) or following treatment for hydrocephalus (n = 2). Prenatal DSM may have a typical MR pattern, and the prognosis might not be as bad as has previously been reported. In the absence of criterion to predict the hydrovenous cerebral imbalance, it is mandatory to check the parenchyma and the ventricles during the pregnancy.

Unexplained mental retardation: is brain MRI useful?

BACKGROUND: Mental retardation (MR), defined as an IQ below 70, is a frequent cause of consultation in paediatrics. OBJECTIVE: To evaluate the yield of brain MRI in the diagnostic work-up of unexplained MR in children. PATIENTS AND METHODS: The MRI features and clinical data of 100 patients (age 1-18 years) affected with non-progressive MR of unknown origin were compared to an age-matched control group (n=100). Two radiologists conducted an independent review of the MRI scans. RESULTS: Univariate and multivariate analyses showed a higher incidence of brain anomalies in the MR group than in the control group (53 vs 17, OR=5.7 [2.9-11.1]), for signal abnormalities within the periventricular white matter (OR=20.3 [2.6-155.3]), lateral ventricular dilatation (OR=15.6 [2.0-124]), mild corpus callosum abnormalities (shortness, atrophy) (OR=6.8 [1.8-25.6]) and subtle cerebellar abnormalities, including fissure enlargement (OR=5.2 [1.1-26.2]). The diagnostic value of MRI abnormalities was considered good in 5% of patients (Alexander disease n=1, diffuse cortical malformation n=1, leukomalacia n=1, vermian agenesis n=1, commissural agenesis n=1), and weak in 48% of patients, in whom non-specific abnormalities did not lead to a diagnosis. Some clinical features resulted in a significantly higher percentage of abnormal MRI scans: abnormal neurological examination (82% vs 47%, P=0.008), abnormal skull circumference (66% vs 49%, P=0.04). Motor delay was associated with cerebellar abnormalities (P=0.01). CONCLUSIONS: This study confirms the weak diagnostic yield of MRI in mentally retarded children. The use of a control group has enabled us to identify the neuroimaging markers frequently associated with MR. Subgrouping patients according to neuroimaging markers and clinical signs should help identify those who would benefit from molecular studies.

MRI of the fetal posterior fossa.

MRI is a useful tool to complement US for imaging of the fetal posterior fossa (PF). In France, the discovery of a PF malformation in the fetus frequently leads to termination of pregnancy (80% in a personal series). However, despite improved accuracy in the diagnosis of PF abnormalities, prognosis remains uncertain. The first objective of this review is to document the normal MRI landmarks of the developing fetal PF. Because of their thinness, the visibility of the cerebellar fissures is dramatically delayed on MRI compared to macroscopic data. An important landmark is identification of the primary fissure of the vermis, normally seen at around 25-26 weeks' gestation (WG) on the sagittal slice, separating the larger posterior lobe from the anterior lobe (volume ratio around 2:1). The prepyramidal and secondary fissures are usually only identifiable after 32 WG and the hemispheric fissures are difficult to see until the end of pregnancy. Considering the signal changes, high signal on T2-weighted (T2-W) sequences is seen from 25 WG in the posterior part of the brain stem (tegmentum and ascending sensory tracts) related to myelination. The low signal intensities seen within the cerebellum on T2-W images correspond to high cellularity of grey matter (deep nuclei), as there is no myelination within the white matter before 38 WG. The second objective is to highlight the signs highly predictive of a poor neurological prognosis. Lack of pontine curvature or vermian agenesis without a PF cyst (small volume of PF) is greatly associated with poor neurological status. The third objective is to propose a diagnostic strategy in difficult cases where prognosis is important, e.g. the Dandy Walker continuum. Analysis of the cerebellum is often impossible if a PF cyst is present (whatever its nature) as the mass effect usually blurs the foliation and even impairs evaluation of the normal ratio between the posterior and anterior lobes of the vermis. Isolated cerebellar hypoplasias raise the question of prognosis and genetic counselling. Such uncertainties require an amniocentesis and a careful search for other anomalies (cerebral and extracerebral). Unilateral abnormalities of a cerebellar hemisphere can be associated with good neurological status if they are isolated. The final objective is to discuss other rare PF fetal abnormalities, such as vascular malformations and tumours.

Bilateral dysplasia epiphysealis hemimelica: report of two cases.

Dysplasia epiphysealis hemimelica is a rare congenital disorder characterised by unilateral bone overgrowth from large joints, mainly the ankle or knee. We present two cases with bilateral lesions; only two similar cases with bilateral involvement have been reported hitherto. The differential diagnosis is considered.