Photoacoustic oxygenation imaging to identify ischemia/hypoxia injury and necrosis of intestine after acute intussusception: A comparative study with CDFI/CEUS

Acute intussusception is a pediatric abdominal emergency that requires immediate diagnosis and treatment. However, accurately identifying bowel necrosis non-invasively remains challenging with conventional sonography. In our study, we investigated the potential of photoacoustic imaging (PAI) as an innovative method for assessing ischemia/hypoxia injury and intestinal necrosis in cases of acute intussusception. Using PAI, we measured intestinal oxygen saturation (sO₂) levels and total hemoglobin (HbT) in various models of acute intussusception at different time points. Additionally, we evaluated blood supply and ischemia/hypoxia injury using color Doppler flow imaging (CDFI) and contrast-enhanced ultrasound (CEUS). Based on histopathological results, intestinal sO₂ measured by PAI demonstrated optimal diagnostic performance for both ischemia/hypoxia injury and intestinal necrosis, with AUC values of 0.997 and 0.982, respectively, while CDFI and CEUS showed relatively high diagnostic performance for both ischemia/hypoxia injury and intestinal necrosis. In conclusion, PAI represents a promising, non-invasive imaging modality for assessing acute intussusception.