Value of Flat-detector Computed Tomography Angiography with Intravenous Contrast Media Injection in the Evaluation and Treatment of Acutely Ruptured Aneurysms of the AcomA complex: A Single Center Experience in 15 Cases

Optimising image quality in intravenous cerebral cone beam computed tomography

INTRODUCTION

The efficacy of intravenous cerebral Cone Beam Computed Tomography (IV CBCT) is well established; however, image quality has only ever been authenticated by subjective evaluation. The aim of this study was to quantify the factors pertinent to achieving consistent and optimal image quality when performing IV CBCT.

METHODS

Between 1 March 2021 and 30 October 2022, 79 patients received IV CBCT. These candidates were divided into three main acquisition field size categories (22/32, 42 and 48 cm) according to the clinical indication. The images were analysed using both a quantitative assessment and a subjective evaluation. Here, a comparison of Hounsfield units (HUs), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and noise index was conducted for each study and compared relative to the acquisition field size. The subjective analysis was performed in a non-blinded fashion where the diagnostic value (DV) of the exam was determined according to a graded scale. A phantom analysis for each of the acquisition field sizes was conducted and modulation transfer function (MTF) graphed.

RESULTS

Significantly higher HU, SNR, CNR and lower noise indices were achieved with the 42-cm protocol than the 22/32 and 48-cm protocols. Here a greater DV was also reported. The MTF demonstrates marginally improved spatial resolution for the 22-cm protocol, but this is near equivocal for the 32-, 42 and 48-cm protocols.

CONCLUSION

The use of larger acquisition field sizes provides improved image quality when performing IV CBCT as an alternative to intra-arterial (IA) CBCT.

Neuroimaging in Pediatric Stroke

Pediatric stroke is unfortunately not a rare condition. It is associated with severe disability and mortality because of the complexity of potential clinical manifestations, and the resulting delay in seeking care and in diagnosis. Neuroimaging plays an important role in the multidisciplinary response for pediatric stroke patients. The rapid development of adult endovascular thrombectomy has created a new momentum in health professionals caring for pediatric stroke patients. Neuroimaging is critical to make decisions of identifying appropriate candidates for thrombectomy. This review article will review current neuroimaging techniques, imaging work-up strategies and special considerations in pediatric stroke. For resources limited areas, recommendation of substitute imaging approaches will be provided. Finally, promising new techniques and hypothesis-driven research protocols will be discussed.

Neuroimaging of Pediatric Intracerebral Hemorrhage

Hemorrhagic strokes account for half of all strokes seen in children, and the etiologies of these hemorrhagic strokes differ greatly from those seen in adult patients. This review gives an overview about incidence and etiologies as well as presentation of children with intracerebral hemorrhage and with differential diagnoses in the emergency department. Most importantly it describes how neuroimaging of children with intracerebral hemorrhage should be tailored to specific situations and clinical contexts and recommends specific imaging protocols for acute and repeat imaging. In this context it is important to keep in mind the high prevalence of underlying vascular lesions and adapt the imaging protocol accordingly, meaning that vascular imaging plays a key role regardless of modality. Magnetic resonance imaging (MRI), including advanced sequences, should be favored whenever possible at the acute phase.