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Contrast-enhanced 3D MR angiography can be used for imaging of children. This technique can improve the delineation of the vasculature that is more anatomically familiar to surgeons. Here we illustrate the usefulness of contrast-enhanced 3D MR angiography in the diagnosis and follow-up of pediatric oncology patients.

Contrast angiography can demonstrate the vascular components of a vascular malformation, but can be technically challenging in small patients with complex venous anomalies. We reviewed the role of magnetic resonance venography (MRV) in the evaluation of children with predominantly low-flow, vascular malformations of the extremities. MRV (2D time-of-flight technique) and magnetic resonance (MR) imaging examinations were performed in ten young patients with congenital predominantly low-flow vascular malformations of the extremities. MR imaging was used to characterize and determine the extent of the malformations, and MRV to evaluate the deep and superficial venous channels. In all patients, MRV studies were reviewed in conjunction with contrast angiograms, considered the gold standard, to confirm the findings. All significant channel anomalies seen with contrast angiography were identified with MRV. In addition, MRV demonstrated some veins that were not intentionally opacified during contrast studies. MRV demonstrates both the superficial and deep conducting veins, whereas contrast angiography is a more directed study, evaluating only those channels intentionally opacified. Together, MR imaging and MRV data can non-invasively form the basis for determining the prognosis and choosing the individual treatment of congenital vascular malformations of the extremities.

Treatment for children with congenital deformities of the lower extremities may vary, depending on the state of the unossified skeletal structures and surrounding soft tissues. The purpose of our study was to demonstrate the spectrum of the osteochondral and extrasosseous abnormalities as depicted with MR imaging. We retrospectively reviewed MR examinations of 13 limbs of ten children (aged 1 month-9 years, mean 2.1 years) with longitudinal and transverse deformities of the lower extremities. The lesions imaged were fibular hemimelia (n = 5), tibial hemimelia (n = 5), and congenital constriction bands (n = 3). Each examination was assessed for abnormalities in the osteocartilaginous and extraosseous (articular or periarticular components such as ligaments, tendons, and menisci; the muscles and the arteries) structures. Abnormalities were seen in all patients. Osteocartilaginous abnormalities in the patients with longitudinal deformities included abnormal distal femoral epiphyses, abnormal proximal tibial physes, hypertrophied and dislocated proximal fibular epiphyses, unsuspected fibular and tibial remnants, and absence or coalition of the tarsal bones. No osteocartilaginous abnormalities were seen in the patients with congenital constriction bands. Articular abnormalities about the knee in patients with either form of hemimelia included absent cruciate ligaments and menisci, dislocated or absent cartilaginous patellae, absent patellar tendons, and abnormal collateral ligaments. All but one limb imaged had absent or attenuated muscle groups. Of the nine MR arteriograms performed at the level of the knee, eight were abnormal. The normal popliteal trifurcation was absent or in an abnormal location. We conclude that MR imaging of children with congenital lower extremity deformities shows many osteochondral and extraosseous abnormalities that are not depicted by conventional radiography. This information can help to plan early surgical intervention and prosthetic rehabilitation.

We reviewed the diastolic blood flow (DBF), pulsatility index (PI), and resistive index (RI) in 211 duplex Doppler ultrasound examinations of 63 pediatric renal transplant recipients. We correlated our findings with the clinical diagnosis, independently determined at the time of ultrasound examination. DBF, evaluated in 202 examinations, was found to be decreased, absent, or reversed in acute rejection (kappa = 0.4, p0.01) and acute tubular necrosis (ATN) (kappa = 0.3, p0.01). The PI and RI were evaluated in 87 and 78 ultrasound examinations respectively. The range of normal PI and RI values in recipients between six and 18 years of age were similar to those reported in adults. However, normal PI and RI values were somewhat higher in recipients less than six years of age who had received adult donor allografts. Overall, the PI was greater than 1.5 in acute rejection (kappa = 0.3, p0.05) and ATN (kappa = 0.3, p0.01), but not in chronic rejection (kappa0, p = NS). The RI was greater than 0.7 in chronic rejection (kappa = 0.3, p0.05) and ATN (kappa = 0.3, p0.05), but not in acute rejection (kappa = 0.03, p = NS). We conclude that the PI and RI vary in pediatric recipients of renal allografts and are not associated with a specific clinical diagnosis.

Over a two-and-one-half year period, 50 children underwent placements of jejunal tubes through a nasal route (NJ, n = 47) or through an existing gastrostomy site (GJ, n = 119). There were four attempted placements (98% success rate). The NJ tubes remained in place an average of 13 days, and the GJ tubes remained in place an average of 37 days. Fluoroscopic time for placement of an NJ tube averaged 6 min (29 cases), and for a GJ tube 8 minutes (91 cases). In spite of the limited retention time, fluoroscopic time, and availability of alternative methods, fluoroscopically placed jejunal feeding tubes are still playing an active role in this institution.

The patency of vascular access shunts and fistulae has been prolonged by a combined surgical and radiological approach that includes percutaneous transluminal angioplasty (PTA), surgical revision, thrombectomy, and thrombolysis. Over the last 3 years, 35 vascular accesses in 27 patients were found to have angiographic abnormality. PTA was performed 32 times on 19 accesses and 7 PTAs resulted in patent accesses by the end of the study. Surgical revision was performed 9 times on 8 accesses and 2 of the surgical revisions resulted in a patent access by the end of the study. Concerning Thomas femoral shunts, PTA prolonged the patency by 2.2 months and surgical revision by 3.8 months per procedure. Concerning arteriovenous (AV) fistulae, PTA prolonged the patency by 4.3 months and surgical revision by 3.5 months per procedure. A combination of procedures effectively doubles the duration of patency of Thomas femoral shunts and almost triples the duration of patency of AV fistulae in children. Forty-one percent of these accesses remain open 1 year following the initiation of these procedures.