Christian J. Kellenberger

Normal right- and left ventricular volumes and myocardial mass in children measured by steady state free precession cardiovascular magnetic resonance

BackgroundQuantification of ventricular volume by Steady State Free Precession (SSFP) cardiovascular magnetic resonance is accurate and reproducible. Normal values exist for adults, but are lacking for children.We sought to establish normal values for left and right ventricular volumes, mass and function in healthy children by using SSFP.Methods and resultsFifty children (27 females, 23 males) without cardiovascular disease were evaluated. Median age was 11 years (range 7 months – 18 years), weight 35 kg (range 7–77 kg), height 146 cm (range 66–181 cm). Thirty-six examinations were performed with breath holding, 14 in freely breathing sedated children.Ventricular volumes and mass were measured in the end systolic and end diastolic phase on SSFP cine images acquired in a short axis plane as a stack of 12 contiguous slices covering full length of both ventricles.Regression analysis showed an exponential relationship between body surface area (BSA) and ventricular volumes and mass (normal value = a*BSAb). Normative curves for males and females are presented in relation to BSA for the enddiastolic volume, endsystolic volume and mass of both ventricles. Intra- and interobserver variability of the measurements was within the limits of 2% and 7% respectively, except for right ventricular mass (10%).ConclusionThe exponential equation for calculation of normal values for each ventricular parameter and graphical display of normative curves for data acquired in healthy children by SSFP cardiovascular magnetic resonance are provided.

Initial experience with FSE STIR whole-body MR imaging for staging lymphoma in children

Our objective was to compare fast spin-echo (FSE) short inversion time inversion recovery (STIR) whole-body MR imaging with standard procedures in staging children with lymphoma. Eight children (age range, 2–16 years) underwent multi-station FSE STIR whole-body MR at initial staging (n=5) or for restaging following completion of therapy (n=5). Whole-body MR and conventional staging procedures, including CT (n=10), gallium-67 scintigraphy (n=9), bone scintigraphy (n=3) and bone marrow biopsy (n=7) were retrospectively compared for detection of sites involved by lymphoma and for the assigned stage. FSE STIR whole-body MR detected more sites of possible lymphomatous involvement at initial staging (87/88) and at restaging (5/5) than did conventional imaging (74/88, 3/5). MR was more sensitive than conventional imaging in detecting bone marrow involvement at initial staging. Following treatment, however, residual and therapy-induced bone marrow signal abnormalities could not be differentiated from lymphomatous involvement. Detection of nodal and visceral involvement correlated well. Our results suggest that FSE STIR whole-body MR imaging is a sensitive technique for evaluating lymphomatous involvement of bone marrow as well as non-marrow sites. Larger prospective trials are needed to determine if FSE STIR whole-body MR can replace standard radiographic procedures for initial staging and contribute in the follow-up of lymphoma in children.

Temporomandibular joint involvement in children with juvenile idiopathic arthritis.

Objective. To determine the rate of temporomandibular joint (TMJ) involvement and find factors associated with TMJ arthritis in a single-center cohort of patients with juvenile idiopathic arthritis (JIA). Methods. Retrospective analysis of all patients with JIA visiting the rheumatology clinic between January 1, 2005, and December 31, 2006. Followup information was included until August 2008. A diagnosis of TMJ arthritis was based on clinical rheumatological and/or radiological findings. Results. After a mean followup time for JIA of 4.6 years (range 0.08–14.17), 86/223 patients (38.6%) had developed TMJ arthritis. The rate of TMJ involvement differed significantly among JIA subtypes (p = 0.0016), with 61% in extended oligoarticular, 52% in polyarticular rheumatoid factor (RF)-negative, 50% in psoriatic, 36% in systemic, 33% in polyarticular RF-positive, 33% in persistent oligoarticular, 30% in unclassified JIA, and 11% in enthesitis-related arthritis. The rate of TMJ involvement in our cohort was statistically significantly lower for patients who were HLA-B27-positive (p = 0.0002). In a multivariate analysis, the association of the following factors was confirmed: JIA subtype (p = 0.0001), a higher erythrocyte sedimentation rate (ESR) at diagnosis (p = 0.0038), involvement of joints of the upper extremity (p = 0.011), the absence of HLA-B27 (p = 0.023), and younger age at onset of JIA (p = 0.050). Conclusion. In our cohort of children with JIA, the overall rate of TMJ involvement was 38.6%. Patients with certain JIA subtypes, a higher ESR at disease onset, involvement of upper extremity joints, and younger age at diagnosis were more likely to develop TMJ arthritis. The presence of HLA-B27 seemed to be protective.

Aortic arch malformations

Although anomalies of the aortic arch and its branches are relatively uncommon malformations, they are often associated with congenital heart disease. Isolated lesions may be clinically significant when the airways are compromised by a vascular ring. In this article, the development and imaging appearance of the aortic arch system and its various malformations are reviewed.

Normal values for aortic diameters in children and adolescents – assessment in vivo by contrast-enhanced CMR-angiography

BackgroundContrast-enhanced CMR angiography (CE-CMRA) is being increasingly used for diagnosing aortic arch anomalies, planning interventions and follow-up assessment. We sought to establish normal values for the diameters of the thoracic aorta and reference curves related to body growth in children using CE-CMRA.ResultsCE-CMRA was performed in 53 children without cardiovascular disease. The median age was 9 years (range 2 – 20 years), weight 30 kg (range 12 – 75 kg), height 131 cm (range 81 – 184 cm), body surface area (BSA) 1.05 m2 (range 0.52–1.9 m2). Aortic diameters were measured at nine standardized sites on oblique maximum-intensity projection (MIP) images. Regression analysis of diameters in relation to BSA demonstrated linear relationship between the cross-sectional aortic diameters and the square root of BSA (BSA0.5). Normative diameters were (0.57 + 19.37*BSA0.5) mm for the aortic sinus, (-3.52 + 18.66*BSA0.5) mm for the first segment of the aortic arch, (-3.37 + 16.52*BSA0.5) mm for the isthmic region and (-1.27 + 9.89*BSA0.5) mm for the descending aorta at the level of the diaphragm. Normative curves are presented.ConclusionThis study provides normative values for aortic diameters in children measured by CE-CMRA. These data may serve for making the diagnosis of pediatric arch anomalies, assessing the need for treatment and planning interventions.

Developmental evidence for obstetric adaptation of the human female pelvis

Significance The obstetrical dilemma hypothesis states that the human female pelvis represents a compromise between designs most suitable for childbirth and bipedal locomotion, respectively. This hypothesis has been challenged recently on biomechanical, metabolic, and biocultural grounds. Here we provide evidence for the pelvis’ developmental adaptation to the problem of birthing large-headed/large-bodied babies. We show that the female pelvis reaches its obstetrically most adequate morphology around the time of maximum fertility but later reverts to a mode of development similar to that of males, which significantly reduces the dimensions of the birth canal. These developmental changes are likely mediated by hormonal changes during puberty and menopause, indicating “on-demand” adjustment of pelvic shape to the needs of childbirth. The bony pelvis of adult humans exhibits marked sexual dimorphism, which is traditionally interpreted in the framework of the “obstetrical dilemma” hypothesis: Giving birth to large-brained/large-bodied babies requires a wide pelvis, whereas efficient bipedal locomotion requires a narrow pelvis. This hypothesis has been challenged recently on biomechanical, metabolic, and biocultural grounds, so that it remains unclear which factors are responsible for sex-specific differences in adult pelvic morphology. Here we address this issue from a developmental perspective. We use methods of biomedical imaging and geometric morphometrics to analyze changes in pelvic morphology from late fetal stages to adulthood in a known-age/known-sex forensic/clinical sample. Results show that, until puberty, female and male pelves exhibit only moderate sexual dimorphism and follow largely similar developmental trajectories. With the onset of puberty, however, the female trajectory diverges substantially from the common course, resulting in rapid expansion of obstetrically relevant pelvic dimensions up to the age of 25–30 y. From 40 y onward females resume a mode of pelvic development similar to males, resulting in significant reduction of obstetric dimensions. This complex developmental trajectory is likely linked to the pubertal rise and premenopausal fall of estradiol levels and results in the obstetrically most adequate pelvic morphology during the time of maximum female fertility. The evidence that hormones mediate female pelvic development and morphology supports the view that solutions of the obstetrical dilemma depend not only on selection and adaptation but also on developmental plasticity as a response to ecological/nutritional factors during a female’s lifetime.

Feasibility of perfusion cardiovascular magnetic resonance in paediatric patients

AimsAs coronary artery disease may also occur during childhood in some specific conditions, we sought to assess the feasibility and accuracy of perfusion cardiovascular magnetic resonance (CMR) in paediatric patients.Methods and resultsFirst-pass perfusion CMR studies were performed under pharmacological stress with adenosine and by using a hybrid echo-planar pulse sequence with slice-selective saturation recovery preparation. Fifty-six perfusion CMR examinations were performed in 47 patients. The median age was 12 years (1 month-18 years), and weight 42.8 kg (2.6-82 kg). General anaesthesia was required in 18 patients. Mean examination time was 67 ± 19 min. Diagnostic image quality was obtained in 54/56 examinations. In 23 cases the acquisition parameters were adapted to patients size. Perfusion CMR was abnormal in 16 examinations. The perfusion defects affected the territory of the left anterior descending coronary artery in 11, of the right coronary artery in 3, and of the circumflex coronary artery in 2 cases. Compared to coronary angiography, perfusion CMR showed a sensitivity of 87% (CI 52-97%) and a specificity of 95% (CI 79-99%).ConclusionIn children, perfusion CMR is feasible and accurate. In very young children (less than 1 year old), diagnostic image quality may be limited.

Ultrasonographic gastric antral area and gastric contents volume in children.

Background:  Cross‐sectional gastric antral area (GAA) measurements by ultrasonography (US) have been proposed for preoperative assessment of gastric volume in adults but not been validated in children. This study investigates whether in children gastric volumes can be predicted by US performed in different patient positions.

Fasting times and gastric contents volume in children undergoing deep propofol sedation--an assessment using magnetic resonance imaging

Aim:  To investigate the effect of fasting times for clear fluids and solids/non‐clear fluids on gastric content volume using magnetic resonance imaging (MRI).

Conservative management of acute appendicitis in children with hematologic malignancies during chemotherapy-induced neutropenia

The management of acute appendicitis in the febrile neutropenic patient after intensive chemotherapy is controversial. We report our single-center–experience of 5 children diagnosed with appendicitis during febrile neutropenia after chemotherapy for acute leukemia or lymphoma. All patients presented with an isolated appendicitis without signs of overt mucositis or more diffuse enterocolitis. The clinical diagnosis was confirmed by ultrasonography. Perforation with retrocecal abscess was present in 1 patient. Administration of combination antimicrobial regimens including meropenem resulted in complete resolution in all patients. Our observations indicate that acute appendicitis in clinically stable neutropenic cancer patients can be managed conservatively without surgery.