Head Ultrasound and MR Imaging in the Evaluation of Neonatal Encephalopathy: Competitive or Complementary Imaging Studies?

Magnetic resonance (MR) imaging is superior to ultrasonography (US) for the evaluation and prognostication of neonates with neonatal encephalopathy (NE). Nonetheless, US may provide important information early in the course of NE and can be used to document the evolution of lesions. This article provides an overview of useful findings in the US evaluation of infants with NE. Although many of the findings do not appear as conspicuous or as extensively as they do on MR imaging, recognition and familiarity with subtle head US abnormalities may allow head US to play an important complementary role to MR imaging in the evaluation of infants with NE.     

Seeing the Invisible—Ultrasound Molecular Imaging

Ultrasound molecular imaging has been developed in the past two decades with the goal of non-invasively imaging disease phenotypes on a cellular level not depicted on anatomic imaging. Such techniques already play a role in pre-clinical research for the assessment of disease mechanisms and drug effects, and are thought to in the future contribute to earlier diagnosis of disease, assessment of therapeutic effects and patient-tailored therapy in the clinical field. In this review, we first describe the chemical composition and structure as well as the in vivo behavior of the ultrasound contrast agents that have been developed for molecular imaging. We then discuss the strategies that are used for targeting of contrast agents to specific cellular targets and protocols used for imaging. Next we describe pre-clinical data on imaging of thrombosis, atherosclerosis and microvascular inflammation and in oncology, including the pathophysiological principles underlying the selection of targets in each area. Where applicable, we also discuss efforts that are currently underway for translation of this technique into the clinical arena.     

MR Imaging of Neonatal Spinal Dysraphia: What to Consider?

The development of the spinal canal and its contents is highly complex and involves multiple programmed anatomic and functional developmental and maturational processes. Correct and detailed knowledge about spinal malformations is essential to understand and recognize these lesions early (preferably prenatally) to counsel parents during pregnancy, to plan possible intrauterine treatments, and to make decisions about the mode of delivery and the immediate postnatal treatment. This article discusses the imaging findings of the most frequently encountered neonatal spinal malformations and correlates these findings with the relevant embryologic processes. The presented classification is based on a correlation of clinical, neuroradiologic, and embryologic data.     

MR Imaging Evaluation of Cancer Extent: Is There Clinical Relevance?

The traditional methods for selecting women for breast conservation therapy (BCT), coupled with adjuvant radiation therapy, have reduced recurrence rates of BCT to acceptable levels. These recurrence rates are still significant, however. They may be further affected by the application of more anatomically targeted radiation therapy. Preoperative MR imaging should theoretically reduce the local failure rate of BCT by at least 5%, with only a modest increase in the mastectomy rate. The evolution of BCT to include more targeted radiation therapy and ablation should place an even larger emphasis on accurate tumor localization and has the potential to allow BCT to become more prevalent and effective.