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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.

Purpose: To compare fat suppression methods by using spectrally selective fat saturation and section-selective water excitation in standard magnetic resonance (MR) imaging sequences used in day-to-day musculoskeletal practice., Materials and Methods: Eighty-three patients underwent MR examination with a 1.5-T system. The two methods were compared by using three common sequences: T1-weighted spin-echo (SE) imaging performed after contrast material injection (n = 24), intermediate-weighted fast SE (n = 36) imaging, and T2-weighted fast SE (n = 36) imaging. Acquisition times of the sequences and signal-to-noise and contrast-to-noise ratios of bone, muscle, fat, and water for the two methods were compared quantitatively. Images were then qualitatively reviewed by two radiologists who were blinded to the type of fat suppression used. Image quality was scored according to four criteria (homogeneity of fat suppression, susceptibility and foldover artifacts, conspicuousness of lesion, and overall image quality) by using a five-point scale (0, bad; 1, poor; 2, fair; 3, good; and 4, excellent). A paired Student t test was used to compare the quantitative data, and a nonparametric paired-data Wilcoxon signed rank test was used for qualitative analysis., Results: Water excitation allowed a substantial decrease in acquisition time (by up to 50%) for T1-weighted sequences. Quantitative measurements revealed a greater signal-to-noise ratio (P <.01) with water excitation for all three sequences, whereas the contrast-to-noise ratio was greater with water excitation only in intermediate-weighted sequences (P <.01). Qualitatively, water excitation proved statistically better than or equal to fat saturation for all criteria in all imaging sequences (P <.05). Mean scores of overall image quality ranged between 2.5 and 3.0 for fat saturation and 3.4 and 3.7 for water excitation, respectively (P <.05)., Conclusion: Section-selective water excitation is faster than conventional fat saturation and produces images of better quality., (Copyright RSNA, 2002)

Objective: This study evaluated the diagnostic accuracy of high-spatial-resolution sonography in the diagnosis of occult fractures of the waist of the scaphoid., Subjects and Methods: Sonography of the scaphoid bone with a 12-MHz transducer was performed in 54 patients with clinically suspected scaphoid fracture and normal findings on initial radiographs, including specific scaphoid images. Three levels of clinical suspicion were considered: high (20%), moderate (30%), and low (50%). Attention was paid to the continuity of the scaphoid cortex and to the surrounding soft tissues (i.e., hemarthrosis or hematoma). Data from early sonograms were then compared with the results of radiography repeated 10-14 days after the initial trauma. In cases of persistent suspicion despite normal findings on follow-up radiographs, the presence of fracture was evaluated on CT (four patients), MR imaging (one patient), or bone scanning (one patient)., Results: Follow-up examinations proved fracture of the scaphoid waist in five patients. In all patients, diagnosis of fracture was suspected on initial sonograms showing cortical disruption associated with soft-tissue abnormalities. There was one false-positive finding and no false-negative results. Using cortical disruption as a diagnostic criterion, we found the sensitivity, specificity, and accuracy of high-resolution sonography for the depiction of scaphoid fracture to be 100%, 98%, and 98%, respectively. Using soft-tissue abnormalities alone as a criterion, we found the sensitivity, specificity, and accuracy of high-resolution sonography to be 100%, 65%, and 68%, respectively. The overall prevalence of occult fracture was 9%, ranging from 3.7% for low suspicion to 27% for high suspicion of fracture., Conclusion: High-resolution sonography is a reliable and accurate method of evaluating occult fractures of the scaphoid waist. Cortical disruption is the diagnostic key. Soft-tissue abnormalities alone lack specificity.

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.

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.

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.

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.

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., (Copyright 2000 S. Karger AG, Basel.)

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.

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.

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.

Drepanocytosis is one of the qualitative hemoglobinopathies which are the most widespread in the word. In a retrospective study on 16 drepanocytary patients observed at the Bordeaux Children's hospital, 7 patients showed medullar hyperplasia, 10 patients showed vaso-occlusive, and 4 patients showed infections. Medullar hyperplasia: bone demineralisation was the current appearance (47%), cortical thinning down (40.5%). They touch long bone. Thrombosis: bone demineralisation was the current appearance (86.3%) and touch long bone, 1 first appearance right femoral head infarct. Some particular appearances we found. 2 cases of "hand foot syndrome", 1 case ischemic aseptic arthritis and 1 case of vertebra "step staircase". Three salmonella pandiaphysite and 1 tuberculosis spondylodiscite were observed. The authors analyse the major radiological appearances of this hemoglobinopathy and recall the interest in knowing this disease even in low endemicity countries.

Unlabelled: Sickle cell anemia is one of the qualitative hemoglobinopathies which are the most widespread in the world. In a retrospective study on 11 drepanocytary patients (10 SS and 1 SC) observed at the BORDEAUX children's hospital. 3 Processus were identified: Hemolysis: 3 hepatomegaly, 3 splenomegaly, 1 hematochromatosis and 4 pigmentary lithiasis; Thrombosis: 1 infarctus case of spleen, kidney, lung, 1 papillary necrosis and 1 brain vascular ischemic appearance;, Infection: 1 spleen abscess and 1 pneumopathy. In 15% of instances, visceral appearances are allowed to discoverer sickle cell anemia. Hemolysis type appearances were currently observed (63.6%) like pigmentary lithiasis and hepatomegaly. The authors analyze the major radiological appearances of this hemoglobinopathy and recall the interest in knowing this disease even in low endemicity countries.

Hemophagocytic lymphohistiocytosis, a variant of histiocytosis, is characterized by an uncontrolled activation of the cellular immune system, including hepatic mononuclear phagocytic cells. Abdominal ultrasound findings in children are evaluated in this disease. We present six pediatric cases, two with familial and four with sporadic hemophagocytic lymphohistiocytosis, examined by abdominal sonography. Three signs were frequently observed: thickening of the gallbladder wall (all cases), increased periportal echogenicity (four cases), and enlarged lymph nodes in the porta hepatis (four cases). Hepatomegaly, splenomegaly, and ascitic fluid may also be found. These imaging findings are not specific and may be seen in viral hepatitis. However, once hepatitis is excluded, they may suggest the diagnosis of hemophagocytic lymphohistiocytosis in a critically ill child. A bone smear must be done to establish the diagnosis.

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.

Abdominal wall defects include a broad spectrum of structural malformations with variable severity and prognosis. The purpose of prenatal ultrasound examination is to correctly diagnose and classify these malformations according to their localization (particularly their relation to the umbilical cord insertion), their contents, their size and associated malformations or karyotypic abnormalities. Based on this examination, two groups can be distinguished: gastroschisis or omphalocele (when the latter is isolated, in particular without karyotypic abnormalities) which can be surgically corrected at birth, and for which predictive criteria of outcome must be evaluated (vitality of herniated bowel, size and contents of omphalocele); severe malformations (ectopia cordis, cloacal exstrophy, Beckwith-Wiedemann syndrome, short umbilical cord, amniotic band syndrome) for which pregnancy termination could be proposed.

We report five adolescent girls with secondary breast tumours. All were imaged by US and the imaging findings have been analysed. Four girls had rhabdomyosarcoma as the primary malignant disease and one had leukaemia. US features were variable, but most of the cases showed heterogeneous nodules which were quite different from the usual benign lesions (fibroadenoma, abscess, cyst) encountered at this age. The metastases produced a variety of echo characteristics: masses with well-defined margins, hyperechoic foci and sonolucent or hypoechoic nodules with posterior attenuation or lacking posterior enhancement. One lesion was round and heterogeneous with a hyperechoic centre. These US findings in an adolescent girl suggest the need for fine-needle aspiration. Mammograms, when performed, never revealed microcalcifications and were quite difficult to analyse at this age, due to the dense glandular breast tissue.

Numerous diseases can lead to multilocular lesions of the liver. The authors report a rare pediatric case of hepatic granulomas due to Pasteurella multocida: a 7-year-old girl with chronic fever was investigated by sonography and CT scan, demonstrating mesenteric lymph node enlargement and numerous small hepatic lesions. After surgical biopsy, histopathology of the liver specimens showed pyogenic granuloma, with serologic testing positive for Pasteurella multocida. Treatment with a tetracycline and corticosteroids was successful. Pasteurella multocida infection, despite its habitual benign course, should be suspected among differential diagnoses of lymphogranulomatous affections with hepatic involvement. No case of liver and lymph node foci in a child has been previously described.

Aneurysmal bone cysts in the skull vault are reported in two patients 7 and 9 years old, who presented with vomiting and headaches caused by raised intracranial pressure. CT showed the cystic lesion in the diploë, with predominantly inward expansion. Fluid-fluid levels were seen on both CT and MRI; the latter also showed bleeding within the cyst. MR angiography showed compression of the superior sagittal sinus in the second case.

Erdheim-Chester disease is a form of Histiocytosis which involves the adults and is distinct from Histiocytosis X. It is characterized by a constant diaphyseal and metaphyseal bone involvement predominating in the lower links. The diagnosis can readily be envisaged when the typical radiological findings are present. Bone involvement may be isolated and well tolerated, or can be associated with systemic involvement and a severe prognosis. We describe three cases of women aged 46, 50 and 73 years. One patient presented with isolated bone lesions, while the two others had a multiorgan localization. From the three cases and from an extensive review of the literature, we describe the spectrum of bone and visceral lesions that can be seen by imaging. The emphasis is put on lesions of the skeletal system, the retroperitoneum, the nervous system, and the pericardium. Furthermore, the relationships between Erdheim-Chester disease and Histiocytosis X are discussed.

A case of acute torsion of an accessory spleen is reported. In a 15-year-old girl was admitted to hospital with acute abdominal pain. Ultrasonography showed a round, hypoechoic, solid mass. Computed tomography demonstrated a low-density mass with peripheral enhancement after intravenous contrast medium. These findings suggest the presence of a capsule. At laparotomy, the patient was found to have torsion and infarction of an accessory spleen. Sonographic and computed tomographic findings are discussed.

We studied 10 patients with capsular tear of the glenohumeral joint in the rotator interval -- the triangular space separating the supraspinatus and subscapular tendons. The patients, manual laborers and athletic people, had no previous shoulder pain. Tears appeared after forced internal rotation caused by trauma. The pain was anterior and radiated distally. Pain was absent at rest but recurred immediately after activity was resumed. On examination, range of motion was normal. Hawkins' impingement sign and the palm-up test usually caused pain. Radiographic findings were normal. Arthrography showed leakage of contrast medium into the subscapularis fossa. The tear was not visualized with ultrasonography or magnetic resonance imaging. Eight patients underwent an operation consisting of minimal acromioplasty with coracoacromial ligament resection, coracoidplasty, and suture of the rotator interval. All patients had relief of pain and return of full function.

An unusual case of infantile myofibromatosis with foci of calcifications was presented, with atypical age of onset and location. The radiological features of this tumor are not always evocative, and histological examination is necessary for diagnosis.

Background: Lissencephaly (agyria-pachygyria) is a defect in migration of cerebral neurons resulting in failure of cortical gyri to develop. Progress in imaging techniques improves its diagnosis., Population and Methods: The files of 17 patients (ten boys and seven girls), aged 7 months to 16 years, were retrospectively studied. The clinical picture consisted of mental retardation (17 patients), seizures (eight patients), facial dysmorphia (seven patients), axial hypotonia (four patients). CT scan was performed in 16 cases and MRI with T1 and T2 weighted images in all 17., Results: The CT scan identified pachygyria in 12 cases. Cerebral calcifications were seen in four cases. MRI detected typical changes in all 17 cases: thickened cortex and gyri, loss of cortical white matter interdigitations, lack of operculisation of the sylvian fissure. Pachygyria was generalized (six patients) or localized (11 patients). Associated abnormalities were dysgenesis of corpus callosum in three patients, cerebellar hypoplasia in one, deep grey matter heterotopia in one; hypersignal of the white matter was identified on T2 weighted images in five patients., Conclusion: MR imaging permits precise analysis of abnormalities secondary to a defect in neuronal migration.

The majority of scoliosis (80%) and especially the idiopathic scoliosis are simply investigated by plain films of the entire spine with erect frontal and lateral views, and supine frontal view at the initial examination. Repeated erect frontal views are sufficient for the follow-up. The important radiation dose (average of 1.2 mG for the frontal view and 2.2 mG for the lateral views) imposes to reduce the frequency of these radiographs. This radiological study allows: to separate non structural and structural curves; the identification and the measurement of a structural curve, discussion for its etiology, appraisal of its progressiveness, discussion of the operative or non operative treatment, and radiological follow-up. Modern imaging (C.T, C.T myelography, MRI) is indicated only in very particular cases: idiopathic scoliosis with neurological symptoms, congenital scoliosis with structural vertebral abnormalities, especially these with posterior arch abnormalities, and progressive scoliosis in spinal dysplasiae. Painful scoliosis are unusual. If pain is present consideration should be given for diagnosis of an underlying lesion. In this case a relevant strategy using modern imaging becomes useful and will be discussed.

Having found three cases of ectasia of the umbilical recess in the antenatal period we decided to review the embryology and the ultrasound of the anatomy of the portal system. We consider that this is a normal anatomic variant of the portal system because the lesion is asymptomatic and regresses spontaneously.

Metaphyseal sclerotic bone changes associated with benign phaeochromocytoma are very rare in childhood. We report four cases, in each of which the radiographic changes returned to normal after removal of the tumour.

Achalasia of the esophagus is rare in children. The authors report eight cases and emphasize two atypical clinical records: The first one is a 3 month-old infant with respiratory distress and "near miss" Sudden Death Infant Syndrome. The second one is a ten year-old boy with association of achalasia of the esophagus, ACTH insensibility and alacryma. Theses cases are discussed.

Pelizaeus-Merzbacher disease is a rare sex-linked leukodystrophy. Its metabolic basis has not been identified yet and diagnosis in mainly based on clinical findings and pathological investigation. Cerebral biopsy is not always performed because of lack of available therapy. Genetic counseling can be provided if the diagnosis is secured. Four cases are reported, in children with characteristic signs, who underwent magnetic resonance (MR) Imaging. MR Imaging appears to be more sensitive than computed tomography to visualize white matter disease: T1 weighted images suggest hypomyelination, in conformity with abnormal myelination. T2 weighted images show a non specific high signal in the white matter.

A 5-month-old boy presented with a right flank abdominal mass. Plain film of the abdomen showed a vertebral column within the mass. Surgery confirmed the diagnosis of fetus in fetu developed within an ectopic intraperitoneal right testicle. Fetus in fetu differs from teratoma by the presence of axial skeleton and organogenesis. When intratumoral axial skeleton is present, plain films are sufficient for the diagnosis.

Transfontanellar ultrasonography in two neonates demonstrated total agenesis of the corpus callosum: this was confirmed by computed tomography in one case, this not being necessary in the other infant. Diagnostic signs on pneumoencephalography and computed tomography are described, and those observed on supplementary ultrasonography are outlined: absence of the corpus callosum normally observed on ultrasonography, and the radial disposition, in a sagittal section, of the sulci of the internal surface of the cerebral hemispheres, which appears to be specific to this type of malformation. A frontal section shows a very typical "bull's head" deformity of the ventricular system.

The undeniable value of brain ultrasound imaging in the detection of ventricular dilatation is emphasized, and a classification of intracranial calcifications proposed: hyperechogenic, nodular and irregular large images and those without a posterior shadow cone. Comparison between simple films and particularly computed tomography images was conducted in the cases studied.

Based on reports of 9 surgically proven cases, the authors stress the contribution of high-resolution sonography in the work-up of omphalovesical midline anomalies in children. Sonography (US) proved useful, especially in disorders of urachal patency (cystic mass and sinus type of the malformation). In the cystic-type mass (3 cases), a midabdominal echogenic cystic mass was demonstrated. The echogenic content resulted from infectious complication. In the sinus type, an echogenic, thickened, tubular omphalovesical tract (8-15 mm) was visualized. This tubular configuration results from the normal omphalovesical anatomy, as can be demonstrated by high-resolution US. With infection, the fascia surrounding the urachal remnants seems to limit the infection. Differential diagnosis should include vesical duplications anomalies, dystrophic calcifications of the umbilical arteries remnants, and, in case of a solid mass, urachal carcinoma. Ultrasound should be part of the work-up of any suspected urachal or other midline anomaly.

Ultrasound imaging and CT scans were performed in a homogeneous group of five patients with hepatoblastoma. Effectiveness in determining characteristics of the tumor mass and its location and possible vascular extension were compared for the two exploratory methods. Findings suggest that these two examinations are useful and complementary for the diagnosis and follow up of hepatoblastoma.

Ultrasonography investigations of retroperitoneal tumors in children were conducted in 25 cases: 11 nephroblastomas, 11 neuroblastomas, 2 ganglioneuromas, and 1 rhabdomyosarcoma. Ultrasonographic exploration of such tumors should include analysis of the mass: echostructure, limits, interfaces and dimensions, and analysis of its extension. The latter should determine the position in relation to the median line, the condition of the large vessels (inferior vena cava and aorta), the homolateral renal cavities and the contralateral kidney, and the presence or absence of glandular spread and hepatic metastases. The semiology of each of these elements is described and discussed, to determine their individual diagnostic value.

The authors report a case of giant Meckel's diverticulum, presenting as a subumbilical abdominal mass, associated with an infectious picture and anemia in a 16 month-old boy. Epidemiologic, pathologic and clinical features of this rare disorder are reviewed as are the diagnostic means. The differential diagnosis with other cystic masses of the umbilical area (omphalo-mesenteric duct cyst, urachal cyst, mesenteric cyst, duplication) is discussed.

Four cases of neonatal multicystic dysplasia involving the upper part of a complete duplex kidney are presented. This malformation, suspected on antenatal ultrasound examination, was confirmed by postnatal IVP and ultrasound. This emphasizes the need to perform an IVP when the diagnosis of multicystic kidney is suggested by ultrasound. Conservative surgery may then be achieved, as in three of the four cases.

Retroperitoneal teratomas are rare in adults; they are malignant in 25.8% of cases. The authors report two benign cases in which radiologic examination was essential in establishing the diagnosis. Irregular calcifications, which are visible in 61.5% of reported cases, cannot be considered a sign of benignity, since 12.5% of calcified tumors were malignant. Because of the indeterminate course of the disease, surgical removal is indispensable.