tailieunhanh - Ultrasound for Surgeons - part 5

Quét ngang vùng bụng dưới bên phải cho thấy một cấu trúc isoechogenic bao quanh bởi một vòng hypoechogenic (bên phải). Quét theo chiều dọc của vùng bụng dưới bên phải cho thấy một phụ lục mở rộng (bên trái) với sự tích lũy chất lỏng. | Appendicitis 63 Figure 12. Transverse scan of the right lower abdomen shows an isoechogenic structure surrounded by a hypoechogenic ring right . Longitudinal scan of the right lower abdomen shows an enlarged appendix left with fluid accumulation. 5 Figure 13. Longitudinal scan of the right lower abdomen shows an appendicolith F with acoustic shadow at distal end of appendix oblique arrow adjacent to cecum C . hyperechogenic foci with acoustic shadowing and vary in size shape and number. They may be seen within the appendiceal lumen or surrounded by a periappendiceal abscess after perforation without recognizable appendiceal landmarks. Local 64 Ultrasound for Surgeons 5 Figure 14. Longitudinal scan of the right lower abdomen shows a mass formation oblique arrow with air density adjacent to the cecum. periappendiceal fluid collections are usually localized to the right lower quadrant of the abdomen or pelvis. They have a round configuration and have a mass effect on adjacent structures. The collections are anechogenic or hypoechoic structure. Loss of echogenic submucosal ring may be focal or diffuse. This finding may represent extension of the inflammatory process through the muscularis propria into the submucosa with subsequent submucosal ulceration and necrosis. A periappendiceal mass Fig. 14 may have poorly defined borders representing thickness of adjacent atonic bowel loops or fluid pockets phlegmon or abscess. Occasionally the appendix can not be seen by sonography. Child A sonogram was interpreted as appendicitis if one wall of the compressed appendix was more than 2 mm thick or the total outer wall to wall diameter of the appendix was more than 6 mm. Pitfalls False Positive Appendicitis Occasionally the normal appendix can have a diameter of more than 7 mm. This can be mistaken for an inflamed appendix. Spontaneously resolving appendicitis is Appendicitis 65 one of the causes of false positive findings. The false positive sonographic findings may be .