Aim of the Study: We herein evaluated a novel ultrasound technique, Superb Micro-vascular Imaging (SMI), in the fields of pediatric surgery. SMI uses advanced clutter suppression to extract flow signals from vessels and depict an image of flow without using contrast. SMI helps us to observe very small vascular structures that previously were not visible.
Methods: Two hundred and eleven pediatric patients, with a total of 343 SMI examinations, were enrolled in this study. The Aplio 300 and 400 ultrasound systems (Toshiba Medical, Japan) were used. Linear probe, PLT-704SBT, was mainly used to observe the fine blood flow of target tissue. Subjects underwent conventional ultrasound examinations including Doppler imaging followed by SMI. SMI findings were compared with those of standard imaging. All examinations were performed without sedation.
Main Results: The average age was 4 years, with 151 males and 60 females. The clinical diagnoses were gastrointestinal disorders in 64 patients, hepatobiliary in 55, genitourinary in 54 and others in 38. The target organs for SMI were the testis in 65 patients, liver in 60, rectum in 33, small intestine or colon in 24, lymph node in 11, appendix in 9, kidney in 6 and others in 13. SMI demonstrated excellent visualization of microvascular structures in the solid tissues including testis, liver and lymph node. Particularly, for patients with fibrotic liver or metabolic disorder, a decreased number of microvessels and abnormal branching of vessels were often observed. In the intestinal walls in appendicitis, enterocolitis and intestinal obstruction, vascular flow changes were well visualized, which helped us to determine the operative indications.
Conclusion: SMI is especially useful for depicting the microvascular flow. We emphasize that SMI can aid in the diagnosis and treatment planning of the diseases in pediatric surgery.