<prompt> Answer this question truthfullyWhat diagnostic study is typically preferred for diagnosing sacrococcygeal teratoma?  <response>: <reason> Ultrasound is the diagnostic study of choice for sacrococcygeal teratoma. Findings on ultrasound include the presence of mass near the distal spine.According to Gonzalez-Crussi System, sacrococcygeal teratoma is graded on a scale from 0 - 3 based on the histology: Grade Microscopic Features Grade 0 Tumor contains only mature tissue. Grade I Tumor contains rare foci of immature tissue. Less than 10 tissue is immature Grade II Tumor contains moderate quantities of immature tissue. Upto 10 - 50 tissue is immature Grade III Tumor contains large quantities of immature tissue with or without malignant yolk sac elements. More than 50 tissue is immature 