MR Imaging of Pediatric Brain Tumors.

Primary brain tumors are the most common solid neoplasms in children and a leading cause of mortality in this population. MRI plays a central role in the diagnosis, characterization, treatment planning, and disease surveillance of intracranial tumors. The purpose of this review is to provide an overview of imaging methodology, including conventional and advanced MRI techniques, and illustrate the MRI appearances of common pediatric brain tumors.

Gorham Stout disease of the temporal bone with cerebrospinal fluid leak.

Gorham Stout disease (GSD) is a rare disease characterized by the proliferation of endothelial lined vessels and replacement of bone by fibrous tissue. The main imaging features are progressive osteolysis and cortical resorption. Temporal bone involvement is rare but presents as a destructive bone lesion that may be misinterpreted as more common lytic processes in the pediatric population, such as infection or Langerhans cell histiocytosis. GSD of the temporal bone is associated with cerebrospinal fluid (CSF) leaks, may present with otorrhea, and can mimic other causes of ear drainage. Here, we report the clinical course, imaging features, and outcomes of a 3-year-old girl with GSD of the temporal bone presenting with CSF leak initially attributed to infection.

Is Gadolinium Contrast Necessary for Pituitary MRI in the Evaluation of Pediatric Short Stature and Growth Hormone Deficiency?

INTRODUCTION: Short stature is a common concern that necessitates pediatric endocrinology evaluation. Growth hormone deficiency (GHD) is a commonly considered etiology. Brain and pituitary magnetic resonance imaging (MRI) with gadolinium-based contrast agents (GBCAs) is the most widely used imaging in assessing patients with GHD. Given the significant strides made in MRI technology, the need for contrast material should be reassessed. METHOD: We performed a retrospective review of healthy patients with short stature and/or GHD who underwent brain and pituitary MRI with and without contrast to assess the added value of contrast administration. RESULTS: 227/318 identified patients underwent growth hormone (GH) stimulation testing; 28 (12.3%) with normal GH response and 62 (27.3%) with severe GHD. We found a low incidence of sellar and suprasellar pathologies. When comparing noncontrast and contrast MRI, we found perfect agreement in detecting abnormal posterior pituitary bright spots (kappa:1.0) and substantial agreement in detecting pars intermedia cysts and posterior superior sellar cysts (kappa: 0.74 and 0.71, respectively). Initially, only moderate agreement was found in detecting infundibular abnormalities (kappa: 0.51), although a revised noncontrast MRI protocol with high-resolution 3D images enabled visualization of the infundibulum. CONCLUSION: The MRI evaluation of healthy patients with short stature and/or isolated GHD may be completed without the use of GBCAs. The slight overestimation of pituitary stalk interruption by noncontrast images can be overcome by adding newer high-resolution sequences.

MRI of Pediatric Orbital Masses: Role of Quantitative Diffusion-weighted Imaging in Differentiating Benign from Malignant Lesions.

PURPOSE: To systematically evaluate the utility of different magnetic resonance imaging (MRI) features, including quantitative diffusion-weighted imaging, in differentiating benign from malignant pediatric orbital masses. METHODS: The use of MRI in 40 pediatric patients with orbital masses was retrospectively reviewed. Multiple subjective and objective MRI parameters, including lesion mean apparent diffusion coefficient (ADC) values and lesion-to-thalamus ADC ratio were recorded. Bivariate analysis was done to identify parameters that were significantly different between benign and malignant subgroups. Receiver operating curves were used to establish optimal cut-off values for lesion mean ADC and lesion-to-thalamus ADC ratio for predicting benign versus malignant lesions. RESULTS: Lesion mean ADC, lesion-to-thalamus ADC ratio and extent of contrast enhancement showed statistically significant differences between the two subgroups. For distinguishing benign from malignant lesions, a lesion mean ADC cut-off value of 1.14â€¯× 10-3 mm2/s provided a sensitivity of 84% and specificity of 100%, while an ADC ratio of 1.4 provided a sensitivity of 81% and specificity of 89%. CONCLUSION: Quantitative diffusion-weighted imaging can be a useful adjunct in characterizing pediatric orbital masses by MRI, and thus help in clinical decision making.

ACR Appropriateness Criteria® Neck Mass-Adenopathy.

A palpable neck mass may be the result of neoplastic, congenital, or inflammatory disease. Older age suggests neoplasia, and a congenital etiology is more prevalent in the pediatric population. The imaging approach is based on the patient age, mass location, and clinical pulsatility. Underlying human papillomavirus-related malignancy should be considered in all age groups. Although the imaging appearance of some processes in the head and neck overlap, choosing the appropriate imaging examination may allow a specific diagnosis, or a limited differential diagnosis. Tissue sampling is indicated to confirm suspected malignancy. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Scoliosis-Child.

Scoliosis is frequently encountered in childhood, with prevalence of 2%. The majority is idiopathic, without vertebral segmentation anomaly, dysraphism, neuromuscular abnormality, skeletal dysplasia, tumor, or infection. As a complement to clinical assessment, radiography is the primary imaging modality used to classify scoliosis and subsequently monitor its progression and response to treatment. MRI is utilized selectively to assess for neural axis abnormalities in those at higher risk, including those with congenital scoliosis, early onset idiopathic scoliosis, and adolescent idiopathic scoliosis with certain risk factors. CT, although not routinely employed in the initial evaluation of scoliosis, may have a select role in characterizing the bone anomalies of congenital scoliosis and in perioperative planning. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Headache-Child.

Headaches in children are not uncommon and have various causes. Proper neuroimaging of these children is very specific to the headache type. Care must be taken to choose and perform the most appropriate initial imaging examination in order to maximize the ability to properly determine the cause with minimum risk to the child. This evidence-based report discusses the different headache types in children and provides appropriate guidelines for imaging these children. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Neural preservation underlies speech improvement from auditory deprivation in young cochlear implant recipients.

Although cochlear implantation enables some children to attain age-appropriate speech and language development, communicative delays persist in others, and outcomes are quite variable and difficult to predict, even for children implanted early in life. To understand the neurobiological basis of this variability, we used presurgical neural morphological data obtained from MRI of individual pediatric cochlear implant (CI) candidates implanted younger than 3.5 years to predict variability of their speech-perception improvement after surgery. We first compared neuroanatomical density and spatial pattern similarity of CI candidates to that of age-matched children with normal hearing, which allowed us to detail neuroanatomical networks that were either affected or unaffected by auditory deprivation. This information enables us to build machine-learning models to predict the individual children's speech development following CI. We found that regions of the brain that were unaffected by auditory deprivation, in particular the auditory association and cognitive brain regions, produced the highest accuracy, specificity, and sensitivity in patient classification and the most precise prediction results. These findings suggest that brain areas unaffected by auditory deprivation are critical to developing closer to typical speech outcomes. Moreover, the findings suggest that determination of the type of neural reorganization caused by auditory deprivation before implantation is valuable for predicting post-CI language outcomes for young children.

ACR Appropriateness Criteria® Back Pain-Child.

It is now generally accepted that nontraumatic back pain in the pediatric population is common. The presence of isolated back pain in a child has previously been an indication for imaging; however, recently a more conservative approach has been suggested using clinical criteria. The presence of constant pain, night pain, and radicular pain, alone or in combination, lasting for 4 weeks or more, constitute clinical red flags that should prompt further imaging. Without these clinical red flags, imaging is likely not indicated. Exceptions include an abnormal neurologic examination or clinical and laboratory findings suggesting an infectious or neoplastic etiology, and when present should prompt immediate imaging. Initial imaging should consist of spine radiographs limited to area of interest, with spine MRI without contrast to evaluate further if needed. CT of the spine, limited to area of interest, and Tc-99m bone scan whole body with single-photon emission computed tomography may be useful in some patients. The addition of intravenous contrast is also recommended for evaluation of a potential neoplastic or infectious process. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Utility of Double Inversion Recovery Sequences in MRI.

Investigators from the Mayo Clinic, Rochester Minnesota investigated the utility of three-dimensional (3D) double inversion recovery (DIR) sequences in magnetic resonance imaging (MRI) detection of focal cortical dysplasia (FCD) in children and young adults with epilepsy.

Imaging findings of anaplastic astrocytoma in a child with maple syrup urine disease: a case report.

Maple syrup urine disease (MSUD) is an inborn error of branched-chain amino acid metabolism, which usually presents in childhood with encephalopathy due to cerebral edema and dysmyelination. Even with treatment, metabolic stressors may precipitate later episodes of acute decompensation. Changes related to cerebral and white matter edema have been described by magnetic resonance imaging (MRI), and imaging can aid in both initial diagnosis and evaluation of decompensation. To date, there are no published known reports of cancer in patients with MSUD. Here, we present the first case report of an anaplastic astrocytoma in a teenager with MSUD, with a discussion of imaging findings and the use of magnetic resonance spectroscopy (MRS) to help distinguish between tumor and metabolic changes.

Imaging of pediatric head and neck masses.

Medical imaging is an important tool in the evaluation and classification of pediatric head and neck masses. Such lesions may include congenital, inflammatory, infectious, vascular, or neoplastic processes. Ultrasound is often the first line modality in the workup of a neck mass in a child, followed by MRI or CT depending on the scenario. This information must be interpreted in the context of the patient's clinical history, physical examination, and demographics. The medical imaging workup of a neck mass in a child must be focused to yield the maximum information possible while minimizing the risks of radiation and sedation.

A multinational, multidisciplinary consensus for the diagnosis and management of spinal cord compression among patients with mucopolysaccharidosis VI.

Cervical cord compression is a sequela of mucopolysaccharidosis VI, a rare lysosomal storage disorder, and has devastating consequences. An international panel of orthopedic surgeons, neurosurgeons, anesthesiologists, neuroradiologists, metabolic pediatricians, and geneticists pooled their clinical expertise to codify recommendations for diagnosing, monitoring, and managing cervical cord compression; for surgical intervention criteria; and for best airway management practices during imaging or anesthesia. The recommendations offer ideal best practices but also attempt to recognize the worldwide spectrum of resource availability. Functional assessments and clinical neurological examinations remain the cornerstone for identification of early signs of myelopathy, but magnetic resonance imaging is the gold standard for identification of cervical cord compression. Difficult airways of MPS VI patients complicate the anesthetic and, thus, the surgical management of cervical cord compression. All patients with MPS VI require expert airway management during any surgical procedure. Neurophysiological monitoring of the MPS VI patient during complex spine or head and neck surgery is considered standard practice but should also be considered for other procedures performed with the patient under general anesthesia, depending on the length and type of the procedure. Surgical interventions may include cervical decompression, stabilization, or both. Specific techniques vary widely among surgeons. The onset, presentation, and rate of progression of cervical cord compression vary among patients with MPS VI. The availability of medical resources, the expertise and experience of members of the treatment team, and the standard treatment practices vary among centers of expertise. Referral to specialized, experienced MPS treatment centers should be considered for high-risk patients and those requiring complex procedures. Therefore, the key to optimal patient care is to implement best practices through meaningful communication among treatment team members at each center and among MPS VI specialists worldwide.