Delayed fenestration of Blake's pouch with or without vermian hypoplasia: fetal MRI at 3 tesla versus 1.5 tesla.

BACKGROUND: Fetal magnetic resonance imaging (MRI), mainly performed at standard field strength, plays a role in the classification of posterior fossa malformations. In the context of early second-trimester screening, upward rotation of the cerebellar vermis per se is usually compatible with a more favorable outcome than Dandy-Walker malformation and profound vermian hypoplasia. Delayed fenestration of Blake's pouch may either mimic vermian hypoplasia by compression or be associated with it in individual cases. To increase specificity, there is a growing interest in the use of high-field MRI which is believed to be safe as long as the specific absorption rate is kept within accepted limits. We aim to illustrate its added value during the second and third trimester. CASE PRESENTATION: In the first case, fetal MRI at 1.5 Tesla was performed at 21 and 27 weeks' gestation with sonographic follow up postnataly. In the second case, 3 Tesla MR images were acquired at 21 and 34 weeks' gestation as well as in the neonatal period. CONCLUSIONS: This pictorial case vignette supports the suggestion that mid-gestational MRI at 3 Tesla has the potential to exclude pronounced vermian hypoplasia with higher confidence than at 1.5 Tesla. However, the discrimination of mild hypoplasia from slight deformation of the cerebellar vermis will likely remain challenging.

Forearm fractures in children: split opinions about splitting the cast.

BACKGROUND: Fractures of the forearm are the most common fractures in children. Various methods of cast immobilization have been recommended. Currently, there is still controversy regarding the optimal method of treatment, especially regarding the need for cast splitting. METHODS: We conducted a single-center randomized and controlled trial between June 2008 and September 2009. Children younger than 16 years presenting to the emergency department with a closed fracture of the forearm needing reduction were eligible for random assignment to immobilization in a closed or split circumferential semirigid cast. The primary outcome was the incidence of cast-related soft-tissue problems such as compartment syndrome, neurovascular compromise, saw burns, or skin breakdown. The secondary outcome was fracture stability. RESULTS: During this period, 100 patients were randomly assigned to one of the two procedures and analyzed. Follow-up was completed in 99 patients. No compartment syndrome was observed in either group. Moderate skin breakdown (< 2 cm(2)) occurred in two patients, one in the closed cast and one in the split cast group. Secondary splitting was necessary in one patient because of a reversible lymphedema. Significant secondary displacement of the fracture was slightly more common in the split group (5 of 50 patients [10%] vs. 4 of 49 patients [8%] in the closed cast group) without reaching statistical significance. CONCLUSIONS: No significant difference in the incidence of cast-related problems was observed between the groups. Fracture stability was comparable in both groups. We suggest that closed circumferential semirigid casts are a safe and effective immobilization technique for fractures of the forearm in children and splitting can be omitted.

Size, shape and age-related changes of the mandibular condyle during childhood.

OBJECTIVE: To determine age-related differences in the size and shape of the mandibular condyle in children to establish anatomical reference values. METHODS: A total of 420 mandibular condyles in 210 children (mean age, 7 years) were retrospectively analysed by using computed tomography (CT) imaging. The greatest left-right (LRD) and anterior-posterior (APD) diameters and the anteversion angles (AA) were measured by two readers. An APD/LRD ratio was calculated. The shape of the condyles was graded into three types on sagittal images. Correlations of parameters with the children's age were assessed by using Pearson's correlation analyses. RESULTS: The LRD (mean, 14.1 ± 2.4 mm), APD (mean, 7.3 ± 1.0 mm) and LRD/APD ratio (mean, 1.9 ± 0.3) increased (r (LRD) = 0.70, p < 0.01; r (APD) = 0.56, p < 0.01; r (rat) = 0.28, p < 0.01) while the AA (mean, 27 ± 7°) decreased significantly (r (antang) = -0.26, p < 0.001) with age. The condylar shape as determined on sagittal images correlated significantly with age (r = 0.69, p < 0.05). Boys had significantly higher anteversion angles (p < 0.01), greater LRDs (p < 0.05) and greater mean ratios (p < 0.05). CONCLUSION: The mandibular condyle is subject to significant age-related changes in size and shape during childhood. As the size of the condyles increases with age, the anteversion angles decrease and the shape of the condyle turns from round to oval.

When coughing can cause stroke--a case-based update on cerebral air embolism complicating biopsy of the lung.

Introducing gas to the circulation is a largely iatrogenic problem which can result in serious morbidity and even death. We report a case of CT-guided needle biopsy of a pulmonary lesion complicated by acute stroke. The English literature on cerebral air embolism is reviewed, including an update of current opinions on its pathomechanism, diagnostic findings, therapeutic strategies, and means of prevention.