Figure 1.
Only the modified Alvarado scores and the CT results were considered during decision making for appendectomy. Positive CT results were defined when three radiologic features (≥6 mm in diameter, enhancement of periappendiceal fat, and wall thickening) were seen at the same time. CT, computed tomography; US, ultrasonography; SWE, shear wave elastography.
Figure 2.
Gray-scale ultrasonography and shear wave elastography in a 47-year old female patient with appendicitis.
A. Gray-scale ultrasonography was 9.9 mm in diameter. The echogenicity of periappendiceal fat and the appendiceal wall thickening were also noted (not shown). B. Elastic modulus scales (mean Q-Box) by shear wave elastography were 26.0, 20.9, and 22.5 kilopascal (kPa) in the anterior, medial, and posterior wall of the appendix, respectively. The highest elastic modulus scale (26.0 kPa) was selected for analysis. The modified Alavarado score of this patient was 7, and computed tomography showed a larger diameter (≥6 mm), enhancement of periappendiceal fat and wall thickening. The histopathology result showed appendicitis.
Figure 3.
Gray-scale ultrasonography and shear wave elastography in a 24-year-old male patient with no appendicitis.
A. Gray-scale ultrasonography was 5.8 mm in diameter. No echogenicity of periappendiceal fat or appendiceal wall thickening were noted. B. Elastic modulus scales (mean Q-Box) by shear wave elastography were 5.5, 11.2, and 4.2 kilopascal (kPa) in the anterior, medial, and posterior wall of the appendix, respectively. The highest elastic modulus scale (11.2 kPa) was selected for analysis. The modified Alavarado score in this patient was 5, and computed tomography showed a smaller diameter (<6 mm), no enhancement of periappendiceal fat, and the absence of appendiceal wall thickening. This patient was diagnosed with terminal ileitis and recovered without surgical intervention.
Table 1.
Patient characteristics.
Table 2.
Imaging results compared with final diagnosis.
Table 3.
Diagnostic ability of gray-scale ultrasonography, shear wave elastography, and computed tomography in patients with suspected appendicitis.