Abstract:

Objective To investigate the clinical value of dual energy (DE) scan technique with selective photon shield (SPS) for the CT angiography (CTA) diagnosis of intracranial aneurysms. Methods Seventy patients with clinically suspected intracranial aneurysms were examined by the CTA and three dimensional digital subtraction angiography (3D-DSA) one week later. SPS-DE technology was used for CT scanning and the image quality of SPS-DE-CTA was subjective rated. The locations and numbers of aneurysm, display degree of aneurysmal neck, long and short diameters of aneurysm, and sizes of aneurysmal neck indicated by two methods were compared and analyzed. Results The image quality of SPS-DE-CTA was over 4 scores, which could satisfy the diagnostic requirements. The 3D-DSA was referred to as the diagnostic standard and the sensitivity, specificity, prediction values of the positive and negative, and accuracy of detecting aneurysms by the SPS-DE-CTA were 100%. And 63 aneurysms were detected by the SPS-DE-CTA and the mean long diameter, short diameter, and sizes of aneurysmal neck were （4.96±1.47）mm, （4.01±1.59）mm, and （3.02±0.75）mm, respectively. The 3D-DSA also detected 63 aneurysms and the mean long diameter, short diameter, and sizes of aneurysmal neck were （4.89±1.52） mm, （3.89±1.56） mm, and （2.91±0.73）mm，respectively. With 3D-DSA as the diagnostic standard, the differences of locations and numbers of aneurysms and measurements of two diagnostic methods were not statistically significant (P>0.05). The mean long diameter (r=0.963), short diameter (r=0.968) of aneurysm, and mean size of aneurysmal neck (r=0.856) measured by two diagnostic methods were well correlated (P=0.000). Conclusion The accuracy of SPS-DE-CTA for diagnosing intracranial aneurysms is high and can be used as a routine non-invasive screening method.

Key words: selective photon shield, intracranial aneurysm, angiography