Purpose: To investigate the added value of color Doppler ultrasonography in patients with acute appendicitis, focusing on risk of perforation
Materials & Methods: On retrospective review of ultrasonography with surgically-proven acute appendicitis, fourteen patients underwent simultaneous color Doppler exams. All ultrasonographic exams were analyzed with maximal diameter, maximal mural thickness, intraluminal contents, loss of mural integrity, periappendiceal fat echogenicity, amount of loculated periappendiceal fluid/abscess and the color signal patterns in whole appendix. In each gray-scale ultrasonography and added color Doppler exams, the confidence for probability of perforation was graded using a four point scale (1, no risk; 2, low risk; 3, high risk; 4, definite perforation) and compared with surgical and pathologic reports as reference standards.
Results: Eight of 14 patients were in high risk of perforation including 5 gangrenous and 3 perforated appendicitis on reference standards. The amount of loculated periappendiceal fluid or abscess was not enough to be seen on ultrasonography. Excessively increased periappendiceal fat echogenicity was highly specific regardless of color Doppler ultrasonography but evident in only two patients. Color Doppler ultrasonography was helpful in 8 patients with increased accuracy and confidence for risk of perforation and two specific findings were focal loss of color signal in background increased blood flow of appendix and absence of color signal in the entire appendix. There was no significant association between other characteristics and risk of perforation.
Conclusion: Adding color Doppler ultrasonographic exams improved predictability of perforation with increased accuracy and confidence during routine gray-scale ultrasonography of acute appendicitis.