Doppler ultrasound in the diagnosis of Budd-Chiari syndrome in children after split liver transplantation.

PURPOSE: To assess the capabilities of a velocity ratio>3 for the diagnosis of Budd-Chiari syndrome (BCS) in children after split liver transplantation using Doppler ultrasonography (DUS). MATERIALS AND METHODS: A total of 28 children who underwent liver transplantation using a split procedure were included. There were 11boys and 17girls with a mean age of 3.8years (range: 0.7-12years). Velocity ratio between blood velocity upstream of the anastomosis and that at the level of the inferior vena cava anastomosis was calculated. Sensitivity, specificity and accuracy of DUS for the diagnosis of BCS were estimated using a velocity ratio>3. RESULTS: Eight children (8/28; 29%) had BCS and 20 (20/28; 71%) did not have BCS using the standard of reference. A velocity ratio>3 on DUS yielded 88% sensitivity (95% CI: 53-98%), 80% specificity (95% CI: 58-92%) and 82% accuracy (95% CI: 64-92%) for the diagnosis of BCS. CONCLUSION: A velocity ratio>3 on DUS is a reliable finding for the diagnosis of BCS in children after split liver transplantation.

Cardiac CT or MRI in pediatric practice: Which one to choose?

The different factors involved in the choice of the best cardiovascular imaging examination for pediatric patients are justification, radiation protection, sedation, resolutions (spatial and contrast), morphology or function, intervention and contrast enhancement. Computed tomography is preferable for all coronary artery conditions, any arterial or venous abnormalities in newborns and infants and in the preoperative assessment for tetralogy of Fallot. Magnetic resonance imaging is used for any tumoral or functional assessment, cardiomyopathy or arrhythmia or if the child's participation and/or size of the structures being examined allows using this technique.

Value of diffusion-weighted images in differentiating mid-course responders to chemotherapy for osteosarcoma compared to the histological response: preliminary results.

BACKGROUND: Preoperative diffusion-weighted MRI (DW-MRI) has been described as an efficient method to differentiate good and poor responders to chemotherapy in osteosarcoma patients. A DW-MRI performed earlier during treatment could be helpful in monitoring chemotherapy. OBJECTIVE: To assess the accuracy of DW-MRI in evaluating response to chemotherapy in the treatment of osteosarcoma, more specifically at mid-course of treatment. MATERIALS AND METHODS: This study was carried out on a prospective series of adolescents treated for long-bone osteosarcoma. MR examinations were performed at diagnosis (MRI-1), at mid-course of chemotherapy (MRI-2), and immediately before surgery (MRI-3). A DW sequence was performed using diffusion gradients of b0 and b900. The apparent diffusion coefficients (ADC1, ADC2, ADC3, respectively), their differentials (ADC2 - ADC1 and ADC3 - ADC1), and their variation (ADC2 - ADC1/ADC1 and ADC3 - ADC1/ADC1) were calculated for each of these three time points. RESULTS: Fifteen patients were included. Patients with no increase in ADC showed a poor response to chemotherapy on their histology results. At mid-course, the three calculated values were significantly different between good and poor responders. ADC2 - ADC1 enabled us to detect, with 100% specificity, four out of seven of the poor responders. There was no significant difference in the values at MRI-3 between the two groups. CONCLUSION: DW-MRI performed both at baseline and mid-course of neoadjuvant chemotherapy is an efficient method to predict further histological response of osteosarcoma. This method could be used as an early prognostic factor to monitor preoperative chemotherapy.

[Pediatric thoracic spine radiographs: Comparison of two scintillators]. / Radiographies thoraciques pédiatriques: comparaison de deux détecteurs à mémoire.

PURPOSE: To compare image quality and radiation exposure from pediatric thoracic spine radiographs from two systems, one using a granular structure scintillator and another using a needle structure scintillator with 40% reduction of exposure. PATIENTS AND METHODS: Randomized prospective study of 296 patients divided into 2 groups of 5 weight categories from 4 to 60 kg. Standard technique parameters are used for granular structure scintillators with dose reduction of 40% applied for needle structure scintillators based on results from a phantom study. Image quality based on detectability of 8 anatomical structures for both types of scintillators was assessed by 6 blinded radiologists. Exposure was expressed by DLP. Results underwent statistical analysis. RESULTS: Overall, image quality was superior with corresponding dose reduction between 33-46% according to weight with needle structure scintillators. For the 4 lower weight categories, image quality was identical. CONCLUSION: With image quality at least equal, new needle structure scintillator units allow a dose reduction of about 40%.

[Radiography of scoliosis: comparative dosimetry between conventional technique and digital fluorography]. / Radiographie des scolioses: dosimétrie comparée entre la technique conventionnelle et la fluorographie numérique.

OBJECTIVE: Compare the irradiation delivered in conventional radiography and digital radiography by image intensifier during a scoliosis workup. PATIENTS AND METHODS: Our prospective randomized study included 105 patients, all of whom were identified according to sociodemographic parameters as well as criteria evaluating the quality of the full front spinal x-ray at PA incidence. The entry dose at the scapula and the exit dose in interorbital, thyroid, mammary, and hypogastric projection was measured by thermoluminescent dosimeters. RESULTS: The results of 71 girls and 28 boys, aged a mean 13.8 years with a mean weight of 47 kg were analyzed. At equal image quality, the entry dose was not significantly different between the two techniques; the mean exit dose reduction was 64% during digital acquisition. This reduction involved the interorbital (162%), mammary (43%), and thyroid (309%) regions. However, this system is more irradiating in the hypogastric region (34%). CONCLUSION: The dosimetric evaluation of the different imaging techniques used to explore the entirety of the spine should be part of radiologists' quality standard used to document their work and their choices.

[Percutaneous treatment of cystic lymphangiomas]. / Malformations lymphatiques: traitement percutané.

Management of cystic lymphangioma necessitate for optimal diagnosis and treatment the expertise of a trained multidisciplinary team including dermatologists, radiologists, plastic and vascular surgeons. An initial imaging work-up of these lesions by ultrasound Doppler examination and MR imaging are necessary before treatment planning. Depending of the size, the location, the risk for the adjacent organs, a therapeutic decision may be mandatory. Percutaneous sclerotherapy is a safe and efficient treatment. It is the treatment of choice that must be proposed in first intention.

Localized cervical neuroblastoma: prevention of surgical complications.

OBJECTIVES: The purpose of this study focused on cervical neuroblastoma (NB) was to assess the prognosis, define the most suitable methods of investigation, and evaluate risk factors for complications following primary surgery. METHODS: Between 1990 and 1999, we conducted two consecutive prospective multicentric studies (NBL90 and NBL94) on localized NB. Because the first study (1990-1994) found surgery-related morbidity and mortality, several surgical risk factors (i.e. adhesion to major vessels, size, friability, and dumb bell tumor) were defined and used prospectively as criteria of resectability in the second study (1994-1999). RESULTS: Of 617 cases included in the two studies, 43 involved cervical NB including 17 cervicothoracic tumors. With a median follow-up of 4 years, overall survival and event-free survival rates were 91 and 81%, respectively with no significant difference between cervical or cervicothoracic NB. Seventeen patients were included in the second study; surgery was used as the first line treatment in 11. Full pre-operative work-up was performed in eight patients, demonstrating one or more risk factors in three. The remaining three patients underwent emergency surgery with no pre-operative work-up or only ultrasound: two developed serious complications. All three patients presenting documented risk factors developed post-operative complications versus only two of the eight patients who presented no risk factor (n = 5) or were inadequately evaluated (n = 3) (P = 0.06). None of the five patients in whom full work-up demonstrated no risk factor had post-operative complications (P = 0.02). CONCLUSIONS: Cervical neuroblastoma has a favorable prognosis. Surgery is the treatment of choice but there is a risk of complications. Appropriate pre-operative work-up is mandatory to evaluate resectability. The surgical risk factors defined for our second study seem to be significant predictors of post-operative complications.

[Choledocal cyst associated with congenital cystic duct dilatation: report of two cases]. / Kyste du cholédoque avec dilatation congénitale du canal cystique : à propos de deux cas.

We report two cases of a choledochal cyst associated with dilatation of the cystic duct. This unusual variant of choledochal cyst was explored by ultrasonography and MR cholangiopancreatography.

[Lipoblastoma of the buttock]. / Lipoblastome de la fesse.

Lipoblastoma is an uncommon benign soft tissue tumor arising from embryonal mesenchymal cells. It occurs mostly during early childhood with a predilection for the extremities, trunk, head and neck. This tumor tends to spread locally and no metastatic potential has been reported. Complete surgical resection is mandatory to prevent local recurrence. MRI provides excellent presurgical delineation of the tumor and confirms its fatty nature. Histology demonstrates the presence of lipoblasts in different stages of maturation; cytogenetic evaluation often discloses chromosomal anomalies of tumoral cells. A case of lipoblastoma of the buttock in a 10 month infant associated with anomalies of chromosome 8 is reported.

[Expression of sexual dimorphism in the fetal pelvic girdle]. / Expression du dimorphisme sexuel sur le bassin du foetus.

The objective of this study was to analyse the development of the foetal pelvis in order to define normal anatomic reference values as a function of gender and gestational age. The study population included 500 stillborn foetuses between the gestational ages of 18 and 41 weeks. Those foetuses without known demographic histories were strictly excluded. For each case studied, an AP radiograph was performed with the following parameters measured by two independent observers: pelvic width, inter-iliac width, inter-sciatic nodes, inter-pubic width and bi-ischial width. The correlation between these radiographic measurements and the gestational age as well as the gender was analysed. The result indicated that the inter-ischiatic distance is significantly greater in the female foetus after the 26-27th week of gestation (P < 0.0062). Standard growth for the female and the male foetal pelvis is proposed with potential application in the study of normal and pathological development of the foetus.

Congenital bowing of the long bones in two fetuses presenting features of Stüve-Wiedemann syndrome and Schwartz-Jampel syndrome type 2.

We report two fetuses with congenital bowing of the long bones. Clinical and radiological features led us to consider two conditions: the Stüve-Wiedemann syndrome and the neonatal Schwartz-Jampel syndrome type 2. Similarities between the two syndromes are discussed.

Microcephalic osteodysplastic primordial dwarfism Taybi-Linder type: report of four cases and review of the literature.

Microcephalic and osteodysplastic primordial dwarfism (MODP) types I, II, and III were defined by Majewski et al. in 1982. This group of syndromes was characterized by intrauterine growth retardation, microcephaly, and typical facial appearance with prominent nose and micrognathia. Type II was clearly different, both clinically and radiologically, whereas types I and III shared manifestations. Distinction between the latter two was established on the basis of subtle radiological differences. In 1967, Taybi and Linder described another syndrome with microcephalic congenital dwarfism. There is a consensus that MODP type I and III and Taybi-Linder cephaloskeletal dysplasia represent the same disorder. We report on four patients with MODP type Taybi-Linder syndromes, two of whom were born to unrelated but consanguineous parents, while the other two were sibs. Second-trimester prenatal detection by ultrasonography was possible in one case. Consanguinity in two cases and recurrence among sibs are consistent with autosomal recessive inheritance.

Imaging of vascularized fibular grafts in large bone reconstruction in skeletally immature patients.

OBJECTIVE: To describe the imaging findings of vascularized fibular grafts (VFG) in large bone reconstruction in children and teenagers. DESIGN AND PATIENTS: Fifteen patients aged from 4 to 19 years underwent VFG for bone reconstruction for primary tumors involving bone in 13 cases and for chronic osteomyelitis in 2 cases. Lesions were located in the femur (6 cases), the tibia (6 cases), the humerus, the distal fibula and the ilium. Radiographic follow-up was performed in all patients, radionuclide studies in 12 patients and MRI in 8. RESULTS: Plain films showed a lamellated periosteal reaction on the VFG within 3 weeks following the procedure in all cases. Fusion of VFG and host bone occurred during the first 3 months. Radionuclide uptake of the VFG was seen in all cases but one. MRI showed cortical thickening and conservation of the high signal intensity of fatty marrow on T1-weighted sequences, and periosteal enhancement on dynamic post-contrast studies in all but one of the patients. CONCLUSION: Radionuclide studies and MRI show the periosteal enhancement and assess the viability of the VFG satisfactorily. However, we feel that plain films may be sufficient to ascertain this viability.

Splenic hemangioma--report of three pediatric cases with pathologic correlation.

Splenic hemangioma is a very rare neoplasm in children. We report three cases of splenic hemangioma, two of solitary hemangioma and one of hemangiomatosis. Two patients had hematologic disorders related to hemangioma. Imaging findings of this entity are presented and discussed with emphasis on pathologic correlation.

[Rhabdoid tumor of the neck]. / Tumeur rhabdoïde du cou.

Three pediatric cases of malignant rhabdoid tumor of the neck are described. Clinical data and imaging findings (US, CT and MRI) are stressed. The mass was well defined, containing punctate calcifications in two cases and encasing the vessels in two other cases. Two patients were treated with a chemotherapy regimen according to MMT 89 SIOP protocol, one had chemotherapy and radiotherapy. Two children died of progressive disease; the remaining child who had complete surgical removal of the tumor is on remission 17 months after diagnosis.