Pediatric magnetic resonance angiography: to contrast or not to contrast.

Magnetic resonance (MR) angiography and MR venography imaging with contrast and non-contrast techniques are widely used for pediatric vascular imaging. However, as with any MRI examination, imaging the pediatric population can be challenging because of patient motion, which sometimes requires sedation. There are multiple benefits of non-contrast MR angiographic techniques, including the ability to repeat sequences if motion is present, the decreased need for sedation, and avoidance of potential risks associated with gadolinium administration and radiation exposure. Thus, MR angiography is an attractive alternative to CT or conventional catheter-based angiography in pediatric populations. Contrast-enhanced MR angiographic techniques have the advantage of increased signal to noise. Blood pool imaging allows long imaging times that result in high-spatial-resolution imaging, and thus high-quality diagnostic images. This article outlines the technique details, indications, benefits and downsides of non-contrast-enhanced and contrast-enhanced MR angiographic techniques to assist in protocol decision-making.

Non-contrast magnetic resonance angiography/venography techniques: what are my options?

Non-contrast magnetic resonance (MR) angiography and MR venography techniques are gaining popularity for vascular imaging because they are faster, more forgiving and less costly compared with contrast-enhanced MR angiography. Non-contrast MR angiography also avoids gadolinium deposition, which is especially important in imaging children. Non-contrast MR angiography has an array of specific applications for numerous clinical indications. This review summarizes the non-contrast MR angiography methods and their relative advantages and disadvantages. The paper also guides the reader on which technique to consider when determining the optimal imaging modality for each individual patient.

Ventricular size measurement methods in fetuses considered for prenatal closure of myelomeningocele.

OBJECTIVE: Prenatal closure of myelomeningocele is associated with a reduced rate of hydrocephalus treatment. This need for hydrocephalus treatment is positively correlated with fetal ventricular width. When ventricular width is 15 mm or greater, the benefits of prenatal closure, as a method to decrease hydrocephalus treatment, are reduced. Thus, fetal ventricular size is an important factor when counseling families who are considering intrauterine surgery with mitigation of hydrocephalus as the primary goal. This study sought to determine whether imaging modality (ultrasound [US] vs MRI) and interobserver variability were factors in any ventricular size disparity seen on imaging studies. METHODS: The imaging studies of 15 consecutive fetuses who underwent prenatal myelomeningocele repair at Children's Mercy Fetal Health Center, Kansas City, Missouri, were reviewed. All fetuses were imaged with US and fetal MRI; on average (range), procedures were performed 3.8 (0-20) days apart. Three comparisons were performed to analyze interobserver and intermodality variability in ventricular width measurements: 1) retrospective comparison of dictated ventricular widths measured with MRI and US by pediatric radiologists (PRs) and maternal-fetal medicine specialists (MFMs), respectively; 2) blinded measurements obtained with US by PRs versus initial US-based measurements by MFMs, and blinded measurements obtained with MRI by PRs versus initial MRI-based measurements by PRs; and 3) blinded measurements obtained with MRI by PRs versus those obtained with US. RESULTS: Retrospective comparison showed that measurements with MRI by PRs were on average 2.06 mm (95% CI 1.43-2.69, p < 0.001) larger than measurements with US by MFMs. Blinded measurements with US by PRs were on average larger than dictated measurements obtained with US by MFMs, but by only 0.6 mm (95% CI 0.31-0.84, p < 0.001). When PRs measured ventricular size in a blinded fashion with both US and MRI, the mean width determined with MRI was significantly larger by 2.0 mm (95% CI 1.26-2.67, p < 0.0001). CONCLUSIONS: The ventricular width of these fetuses was larger when measured with MRI than US by an amount that could impact recommendations for fetal surgery. Every center involved in counseling families about the risks and benefits of fetal intervention for spina bifida needs to be aware of these possible imaging-based disparities.

Colostomy Takedown: Ischemic Complication following Anorectal Malformation Surgery.

INTRODUCTION: Anorectal malformations (ARM) are complex disorders that often require staged reconstructions. We present a case and imaging findings of a child who developed issues following colostomy closure due to segmental colonic ischemia. Case Presentation. A 3-year-old female with Currarino syndrome presented with abdominal distention, blood-flecked stools, and prolonged cecostomy flush time. For her anorectal malformation, a colostomy was initially placed. A new colostomy was created at posterior sagittal anorectoplasty (PSARP) to allow the distal rectum to reach the anus without tension. Differentials for her presenting symptoms included a mislocation of the anus, stenosis at the anoplasty site, stricture within the colon, or sacral mass from Currarino syndrome, causing obstructive symptoms. Workup at our hospital included an anorectal exam under anesthesia (EUA), which showed a well-located anus with without stenosis at the anoplasty site, and an antegrade contrast study revealed a featureless descending colon with a 3-4 mm stricture in the distal transverse colon at the site of the previous colostomy, without an obstructing presacral mass. To alleviate this obstruction, the child underwent removal of the chronically ischemic descending colon and a redo-PSARP, where the distal transverse colon was brought down to the anus. She is now able to successfully perform antegrade flushes. CONCLUSION: Patients who have had prior surgeries for ARM repair are at a higher risk of complications, including strictures or ischemic complications at areas of previous surgery or colostomy placement. A thorough preoperative workup, including contrast studies, can alert the surgeon to these potential pitfalls.

Tisagenlecleucel infusion in patients with relapsed/refractory ALL and concurrent serious infection.

BACKGROUND: Tisagenlecleucel, an anti-CD19 chimeric antigen receptor T (CAR-T) cell therapy, has demonstrated durable efficacy and a manageable safety profile in pediatric and young adult patients with relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL) in the ELIANA pivotal trial and real-world experience. Experience from investigator-led studies prior to ELIANA suggests that infections and inflammatory conditions may exacerbate the severity of cytokine release syndrome (CRS) associated with CAR-T cell therapy, leading to extreme caution and strong restrictions for on-study and commercial infusion of tisagenlecleucel in patients with active infection. CRS intervention with interleukin (IL)-6 blockade and/or steroid therapy was introduced late in the course during clinical trials due to concern for potential negative effect on efficacy and persistence. However, earlier CRS intervention is now viewed more favorably. Earlier intervention and consistency in management between providers may promote broader use of tisagenlecleucel, including potential curative therapy in patients who require remission and recovery of hematopoiesis for management of severe infection. MAIN BODY: Patient 1 was diagnosed with B-ALL at 23 years old. Fourteen days before tisagenlecleucel infusion, the patient developed fever and neutropenia and was diagnosed with invasive Mucorales infection and BK virus hemorrhagic cystitis. Aggressive measures were instituted to control infection and to manage prolonged cytopenias during CAR-T cell manufacturing. Adverse events, including CRS, were manageable despite elevated inflammatory markers and active infection. The patient attained remission and recovered hematopoiesis, and infections resolved. The patient remains in remission ≥1 year postinfusion.Patient 2 was diagnosed with pre-B-ALL at preschool age. She developed severe septic shock 3 days postinitiation of lymphodepleting chemotherapy. After receiving tisagenlecleucel, she experienced CRS with cardiac dysfunction and extensive lymphadenopathy leading to renovascular compromise. The patient attained remission and was discharged in good condition to her country of origin. She remained in remission but expired on day 208 postinfusion due to cardiac arrest of unclear etiology. CONCLUSIONS: Infusion was feasible, and toxicity related to tisagenlecleucel was manageable despite active infections and concurrent inflammation, allowing attainment of remission in otherwise refractory pediatric/young adult ALL. This may lead to consideration of tisagenlecleucel as a potential curative therapy in patients with managed active infections.

A radiologic review of common breast disorders in pregnancy and the perinatal period.

The imaging changes in the breast associated with pregnancy and the perinatal period may not only deviate from the baseline appearance for each patient, but may also mimic disease or confound evaluation of disease. The hormonal changes can influence a range of disorders, from benign or inflammatory changes to malignant tumors. Moreover, outcomes differ from those of similar pathologies in nonpregnant patients, owing to either physiological changes or delays in diagnosis and treatment. Ultrasonography is the preferred imaging modality for evaluation during pregnancy and lactation, as its sensitivity for carcinoma is nearly 100% (Sabate JM, Clotet M, Torrubia S, et al, 2007; Radiographics 27 suppl 1:S101-S124). Therefore, an understanding of the specific pregnancy-associated pathologies and their radiologic appearances is indispensable to the interpreting radiologist.