Abstract: Sacral development is a key determinant of bowel and bladder function in children with anorectal malformations (ARM) and sacral agenesis. Accurate radiologic assessment of the sacrum provides essential prognostic information, guiding both surgical planning and long-term management. We aim to review the imaging-based metrics used to evaluate sacral development, highlighting their significance in predicting continence outcomes. ARM result from abnormal development of the hindgut and cloacal membrane between weeks 6 and 9 of gestation. These malformations can vary significantly, ranging from minor anal displacement to complex defects that involve the rectum, vagina, and urethra. Both the anorectal structures and the sacrum develop from the caudal mesoderm during the same period, which means that sacral anomalies, such as hypoplasia or agenesis, often occur alongside ARM. Due to this close embryologic origin, the sacrum can provide important insights into the prognosis of ARM, and specific metrics can offer objective information for assessment. The sacral ratio (SR), derived from anteroposterior (AP) and lateral pelvic radiographs, is the most widely used quantitative measure. It stratifies patients into prognostic categories, with SR ≥ 0.7 indicating good continence potential and SR < 0.4 associated with poor outcomes. However, SR is subject to variability due to patient positioning, pelvic tilt, and image quality. Additional metrics such as the sacral index (SI) and sacral curvature (SC) offer complementary insights. SI reflects sacral width and height and has been correlated with ARM severity. SC provides a qualitative measure of sacral shape and is associated with continence outcomes. These measurements are often limited by the constraints of conventional radiography and the technical challenges of MRI, including non-isotropic data and restricted field of view. This educational exhibit will provide a comprehensive review of sacral measurements in ARM and sacral agenesis. We encourage a standardized and multimodal approach to sacral assessment, and provide information for a deeper understanding of: - Sacral and anorectal malformations embryology - Key radiologic metrics (SR, SI, SC) and their interpretation - Limitations and considerations in measurement techniques - The prognostic significance of sacral development Read More

Meeting name: IPR 2026 Congress , 2026

Authors: Belachew Bethelhem, Silva De Campos Meneses Marcus Otavio, Moreira Vidal Lorenna

Keywords: Anorectal Malformation, Sacrococcygeal, Xray

The spleen is frequently involved in a wide range of pathological processes, yet is insufficiently addressed in the radiology literature for the pediatric population. Understanding the embryological development of the spleen – originating as a mesodermal derivative that initially manifests as a condensation of mesenchymal cells within the dorsal mesogastrium and later translocates to the left side of the abdominal cavity as the stomach rotates – and recognizing its normal appearance in imaging methods are crucial for the accurate diagnosis of pathological processes. These processes vary from focal to diffuse spleen involvement and include anatomical variants (e.g., splenunculus), variations in size (e.g., splenomegaly), in number (e.g., polysplenia and asplenia), and in location (e.g., wandering spleen), as well as vascular (e.g., hemangioma and infarction), traumatic (e.g., lacerations), infectious (e.g., abscess), genetic (e.g., sickle cell disease) and neoplastic abnormalities (e.g., lymphoma and metastasis). Ultrasound is typically the first imaging modality in evaluating the spleen and its lesions; however, CT can provide detailed information in some contexts (e.g., trauma), and MRI offers excellent soft tissue contrast and is useful in cases requiring etiology differentiation (e.g., tumor). Therefore, it is important to understand how these different entities present in different imaging modalities, and what makes them unique. We aim to provide a comprehensive overview of spleen embryological development, and a visual differentiation of both common and uncommon splenic lesions in the pediatric population, highlighting high-yield clinical cases that illustrate key findings. Read More

Meeting name: SPR 2025 Annual Meeting , 2025

Authors: Silva De Campos Meneses Marcus Otavio, Braojos Fernanda, Prodigios Joice, Guarilha Taísa, Rodrigues Santos Luiz Antonio, Souza Antonio

Keywords: Spleen, Multimodality, Splenic