Evaluating anemia on non-contrast thoracic computed tomography.

Area of Science:

• Radiology
• Medical Imaging
• Hematology

Background:

• Anemia is a significant global health issue impacting prognosis and quality of life.
• Non-contrast chest CT may show signs of anemia, such as the "aortic ring sign" and "interventricular septum sign".

Purpose of the Study:

• To evaluate the diagnostic accuracy of subjective and objective criteria for diagnosing anemia on unenhanced thoracic CT scans.

Main Methods:

• Retrospective study of 325 patients undergoing non-contrast chest CT.
• Radiologists assessed subjective signs (aortic ring, interventricular septum).
• Objective blood density was measured at various locations.

Main Results:

• Significant correlation found between blood attenuation and hemoglobin levels (R²=0.61).
• Aortic arch threshold of 20 HU demonstrated best performance for severe anemia detection.
• Aortic ring sign showed higher sensitivity (82.5%) than interventricular septum sign (32%).
• Interventricular septum sign showed higher specificity (87%) than aortic ring sign (99.2%).

Conclusions:

• Anemia detection from unenhanced chest CT is feasible.
• Both objective and subjective criteria exhibit promising sensitivity and specificity for anemia diagnosis.