Pseudo-cysts, lipomas, infarcts and simple cysts of the calcaneus: are there different or related lesions?

Pseudocysts, lipomas, infarcts and simple cysts of the calcaneus are described as different entities in the medical literature. However, some evolutions or associations may suggest a relationship which is not yet demonstrated in all cases. The aim of this article is to describe each lesion and emphasize their different characteristics that may suggest a relationship between them.

Prenatal diagnosis of hypochondroplasia: three-dimensional multislice computed tomography findings and molecular analysis.

We report the first case of sporadic hypochondroplasia diagnosed in utero by computed tomography (CT) three-dimensional (3D) imaging and molecular analysis at 38 weeks' gestation. Prenatal sonographic examinations performed at 32 and 35 weeks' gestation revealed a rhizomelic shortness of the long bones (femur and humerus) with macrocephaly. Based on these findings, a nonlethal form of skeletal dysplasia was suspected and a multislice CT imaging with 3D reconstruction was performed depicting skeletal abnormalities which suggested hypochondroplasia. The prenatal diagnosis was confirmed by DNA mutation analysis of the fibroblast growth receptor 3 gene.

Fetal extradural hematoma: prenatal diagnosis and postmortem examination.

We report the 1st confirmed case of an extradural hematoma diagnosed in utero by ultrasonography and magnetic resonance imaging at 31 weeks' gestation. No signs of intracranial hemorrhage were found. During pregnancy, the expecting mother suffered from sustained cough, and a blood sample test revealed acute pertussis. The presence of fetal hydrocephaly, brain parenchymal deviation, and other abnormalities suggested a poor outcome, and based on these findings pregnancy termination was recommended and carried out. Postmortem examination confirmed the diagnosis of an extradural hematoma in the posterior fossa.

[Practical measurement of radiation dose in pediatric radiology: use of the dose surface product in digital fluoroscopy and for neonatal chest radiographs]. / Mesure pratique de l'irradiation en radiopédiatrie: utilisation du produit dose surface en fluorographie numérique et pour les radiographies pulmonaires néonatales.

PURPOSE: Control of radiation dose in pediatric radiology requires knowledge of the reference levels for all examinations. These data are useful for daily quality assessment, but are not perfectly known for some radiographic examinations. The purpose of our study was to evaluate the dose related to voiding cystourethrograms (VCUG), upper GI (UGI) and intravenous urography (IVU). Neonatal chest radiographs in the intensive care unit were also evaluated. MATERIAL AND METHODS: For examinations with contrast material (478VCUG, 220UGI, 80IVU), the children were divided in groups based on their weight, from 5 to 30 Kg. Measurements were performed using an ionization chamber and expressed with the dose-area product (DAP). For chest radiographs, a direct measurement of the entrance-skin dose was performed, with secondary calculation of the DAP. RESULTS: For VCUGs, the DAP ranged between 42.89cGy.cm2 and 125.41cGy.cm2. The range was between 76.43 and 150.62cGy.cm2 for UGIs and between 49.06 and 83.33cGy.cm2 for IVUs. For neonate chest radiographs, DAP calculations were between 0.29 and 0.99cGy.cm2. CONCLUSION: These values represent our reference doses. They allow continuous monitoring of our radiographic technical parameters and radiographic equipment and help to correct and improve them if necessary.

[Monostotic fibrous dysplasia of the calcaneus: two case reports]. / Dysplasie fibreuse monostotique du calcaneus: à propos de 2 cas.

The authors report two unusual cases of aggressive monostotic fibrous dysplasia involving the calcaneus. This lesion occurs on the 2th decade of life. The main symptom is talalgia. On plain films, differential diagnosis includes aggressive cystic or pseudocystic lesions of the calcaneus. On MR imaging, the tumor matrix is more suggestive of the diagnosis. Treatment of this aggressive form of fibrous dysplasia consists of a surgical curettage completed by cryotherapy and graft because of a high level of recurrence.

[Is the rings and arcs pattern of mineralization specific for chondroid matrix tumors?]. / Les calcifications annulaires sont-elles spécifiques des matrices tumorales cartilagineuses?

The rings and arcs pattern of mineralization is considered pathognomonic for cartilaginous tumors. The authors report four cases of osteoblastomas in which the presence of such a pattern of mineralization mistakenly lead to a diagnosis of cartilaginous tumor. These densities are not explained by the histologic findings.

[Imaging of chilhood and adolescent scoliosis]. / Imagerie des scolioses de l'enfant et de l'adolescent.

Scoliosis is frequent, especially during the peripubertal period, which corresponds to the period of greatest activity. About 75% of scoliosis are idiopathic, while the remaining 25% can be divided into neuromuscular, congenital and miscellaneous etiologies. When it is associated with pain, a comprehensive work up should be undertaken to identify the underlying etiology of the scoliosis. Idiopathic scoliosis is typically evaluated using standard radiographs. The number of follow-up radiographs and radiation exposure must be maintained to a minimum. Radiation safety guidelines and protocols must be implemented. Large cassettes can be replaced by digital acquisitions using units with reconstruction software. The technique of evaluation of these scoliosis series radiographs as well as their results will be reviewed. Recent data regarding the evaluation of spinal and pelvic balance parameters in the standing position will be introduced. Atypical idiopathic and other scoliosis require additional evaluation. Computed tomography, with 2D and 3D reformations, is ideal for evaluation of bony anomalies. MRI is ideal for evaluation of the spinal canal and cord, from the skull base down to the sacrum, for all patients with surgical scoliosis or patients with neurological symptoms. The increased availability of MR imaging has resulted in an increased number of so-called idiopathic asymptomatic scoliosis where an underlying anomaly can be identified.

Abdominal cystic lymphangiomas in children: presurgical evaluation with imaging.

Cystic lymphangiomas are benign vascular tumors which are most often seen in young children. They are considered to be congenital malformations stemming from sequestration of lymphatic tissue. The authors report 15 cases of abdominal location and detail the findings of imaging in the etiologic and topographic diagnosis of these lesions. The initial incidents were essentially the discovery of a palpable abdominal mass, and more rarely, an acute gastrointestinal complication. There was also one case of prenatal diagnosis. Plain films provide only indirect signs related to the displacement of neighboring organs. Ultrasonography permits the etiologic diagnosis by showing an often voluminous, septated cyst. The intra- or retroperitoneal location of the lesion is sometimes difficult to determine by sonography, in which case CT scanning is usually adequate. For abdominal locations, percutaneous sclerosis is not available, and surgical removal is the only treatment for this disorder. The topography of the lesion and the involvement of retroperitoneal structures is important to determine.

MRI and clinical differences between optic pathway tumours in children with and without neurofibromatosis.

The purpose of this study was to evaluate the value of MRI in studying optic pathway tumours associated with neurofibromatosis, and to look for potentially helpful criteria for the management of such lesions. This retrospective study included 14 children with neurofibromatosis type 1 (NF-1) as well as a lesion of the optic pathway. Clinical data and MRI findings were analysed with regard to location, structure and course of the tumours, and were compared with 13 optic pathway tumours in patients without NF-1. The median age of onset was 4.1 years. 11 patients with NF-1 were asymptomatic. In the NF-1 group, the optic nerves were involved in 10 cases without a cystic component at the time of diagnosis. In the non-NF-1 group, the tumour was located in the chiasma in 11 cases; 12 cases had a cystic component. 10 of the NF-1 group had no tumour progression over an average follow-up of 3.2 years without treatment. These findings suggest that optic astrocytomas in association with NF-1 are distinct lesions from isolated optic gliomas. In NF-1, most such tumours show only slight progression, and may correspond to perineural gliomatosis rather than a true pilocytic astrocytoma. Among NF-1 patients, initial MRI provides no prognostic criteria in children who subsequently show tumour progression. Nevertheless, MRI can be useful in establishing the diagnosis of NF-1 and can serve as a baseline study.

Giant cystic Schmorl's nodes: imaging findings in six patients.

OBJECTIVE: We describe the imaging findings of an unusual type of Schmorl's node appearing as giant cystlike lesion of the vertebral bodies. CONCLUSION: Giant cystic Schmorl's nodes are unusual entities; their radiologic appearance differs dramatically from the classic description and is diagnostically challenging. However, the appearance of these nodes on conventional radiographs and especially on MR images is characteristic. Knowledge of this entity would help to eliminate unnecessary invasive diagnostic or therapeutic procedures.

Contribution of transvaginal ultrasonography and fetal cerebral MRI in a case of congenital cytomegalovirus infection.

Cytomegalovirus is the most common cause of congenital viral infection. In utero this infection is usually suspected on the basis of ultrasound findings. We present a case in which routine ultrasound examination demonstrated a decrease in fetal cephalic dimensions at 32 weeks' gestation in an asymptomatic patient. Transvaginal ultrasound revealed echogenic vessels in the thalami and lesions in the subependymal region. Suspected diagnosis of fetal cytomegalovirus infection was confirmed by positive titers of anti-cytomegalovirus-IgM antibodies in fetal blood and amniotic-fluid PCR studies. Fetal cerebral MRI demonstrated parenchymal atrophy and polymicrogyria. The parents decided to terminate the pregnancy, and necropsy confirmed the diagnosis. Suspicion of CMV fetal infection should prompt transvaginal ultrasound and fetal brain MRI.

Capillary haemangioma of the greater omentum in a 5-month-old female infant: a case report.

Capillary haemangiomas are frequent benign tumours in infancy. The authors report a case of capillary haemangioma of the greater omentum, discovered in a child of 5 months of age and studied with US, CT and MRI. The localization of such a lesion in the greater omentum is exceptional. Abdominal US revealed a heterogeneous, multinodular intraperitoneal mass. Doppler study demonstrated hypervascularity of the lesion. CT localized the mass to the greater omentum. The mass was hypodense on the unenhanced scan and enhanced massively after injection. The infant suffered a reaction to contrast medium during the CT. MRI demonstrated a mass which was hypointense on T1-weighted images and hyperintense on T2-weighted images. Laparotomy confirmed the location of the mass within the greater omentum and allowed resection of the tumour.

Anterolateral compartment of the ankle in the lateral impingement syndrome: appearance on CT arthrography.

OBJECTIVE: This article describes the appearance of the anterolateral recess of the posttraumatic ankle on CT arthrography and clearly shows the benefit of this technique in the diagnosis of soft-tissue impingement. MATERIALS AND METHODS: The study was carried out on 44 patients examined by CT arthrography and arthroscopy for chronic, posttraumatic ankle pain. The analysis principally concerned the lateral compartment--in particular, the synovial regularity and the cartilage of the talar dome. RESULTS: Four CT patterns were identified: type 0, uniform filling of the recess with clear limits; type I, intraarticular linear structure outlined by contrast agent; type II, nodular formation in the lateral groove; and type III, irregular appearance of the edges of the lateral groove. Ninety-one percent (10/11) of type II patterns were characterized as meniscoid lesions by arthroscopic examination, 100% (14/14) of type III patterns corresponded to an abundant fibrous reaction, and arthroscopic findings were normal for 100% (2/2) of type 0 patterns and 88% (15/17) of type I patterns. The latter was thus considered as a normal variant outlining the accessory anterior inferior tibiofibular ligament. Type II and III lesions were statistically associated (p = .001) with a chondropathy when time from initial trauma was greater than 22 months. CONCLUSION: CT arthrography provides evidence of anterolateral soft-tissue impingement--in particular, in type II or III patterns. These lesions are statistically associated with a chondropathy.

Brain stem infiltration by mixed Langerhans cell histiocytosis and Chester-Erdheim disease: more than just an isolated case?

Langerhans cell histiocytosis is classically considered as totally different from Chester-Erdheim's disease which consists in the infiltration of various parenchymas by macrophagic CD68-positive histiocytes. We report the case of a 46-year-old woman with a long history of diabetes insipidus who presented typical lesions of Langerhans cell histiocytosis on vulvar and skin biopsies as well as bony cellular infiltrates characteristic of Chester-Erdheim's disease. A few months later she presented cerebellar disorders and died after an 18-month course. At autopsy the pons was enlarged, due to numerous cellular infiltrates which were also scattered in the middle cerebellar pedoncles, dentate nuclei, midbrain and hypothalamus. There were S100-protein positive Langerhans cells intermingled with numerous ovoid CD68-positive histiocytes. There are a few reported cases of Chester-Erdheim's disease presenting foci of Langerhans cells histiocytosis in other parenchymas. In addition, there are 10 reported cases with diabetes insipidus and bilateral infiltration of the brain stem and cerebellum, considered as presenting either one type of histiocytosis or the other. Our case demonstrates that both histiocytoses may coexist in the brain and thus correspond in fact to the same pathology in certain particular cases.

[Para-articular and intraosseous synovial cysts and articular mucoid cysts]. / Kystes synoviaux et kystes mucoïdes articulaires, para-articulaires et intra-osseux.

The authors review the mechanism and imaging findings of intraarticular, juxtaarticular, and intraosseous ganglion cysts. They specially emphasize particular features according to the most frequent locations.

Localised proton magnetic resonance spectroscopy of the brain after perinatal hypoxia: a preliminary report.

OBJECTIVES: Perinatal hypoxic ischaemic injury is a significant cause of neurodevelopmental impairment. The aim of this study was to evaluate localised proton magnetic resonance spectroscopy (1H-MRS) after birth asphyxia. MATERIALS AND METHODS: Thirty newborn infants suspected of having perinatal asphyxia (Apgar score < 3) were studied. The mean gestational age was 37 weeks, mean age at the MR examination was 18 days and mean weight was 2.9 kg. A 1.5-T unit was used for imaging and spectroscopy. None of the babies had mechanically assisted ventilation. No sedation was used. Axial T1-weighted and T2-weighted images were obtained. 1H-MRS was recorded in a single voxel, localised in white matter, using a STEAM sequence. RESULTS: Image quality was good in 25 of 30 babies. 1H-MRS was performed in 19 of 30 subjects, with adequate quality in 16. Choline, creatine/phosphocreatine and N-acetylaspartate peaks and peak-area ratios were analysed. Lactate was detected in four infants. The N-acetylaspartate/choline ratio was lower in infants with an impaired neurological outcome, but the difference was not statistically significant. CONCLUSIONS: This study suggests that 1H-MRS may be useful for assessing cerebral metabolism in the neonate. A raised lactate level and decreased N-acetylaspartate/choline ratio may be predictive of a poor outcome. However, in our experience this method is limited by the difficulty in performing the examination during the first hours after birth in critically ill babies, the problems related to use of a monovoxel sequence, the dispersion of the ratios and the lack of determination of the absolute concentration of the metabolites.