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PURPOSE To investigate the clinical value of wide-detector (8cm) axial nonenhanced cranial CT scan on revolution CT and performance of noise, beam hardening artifacts reduction and radiation dose evaluation compared with standard-detector (4cm) CT scan on Discovery 750HDCT METHOD AND MATERIALS With local ethical committee approval, one hundred subjects who performed head CT scan were enrolled in the study. Fifty subjects were scanned with a wide-cone CT scanner (Revolution CT, GE Healthcare) using widedetector (8 cm) axial protocol, another fifty subjects were scanned with standard-detector (4 cm)CT scanner (Discovery HD 750 CT, GE Healthcare) using helical protocol. The background noise in the corona and the BHA in 4 different anatomic regions (medulla oblongata, cerebellar, pons and the inferior part of frontal lobes) were measured and compared among the three scan protocols above. Beam-hardening artifact was defined as the square root of the squared noise difference between the region of interest and background. Image quality (IQ) of the two groups were compared in terms of HU of the regions of interest, signalnoise-ratio (SNR), contrast-to-noise ratio (CNR) and subjective IQ. The effective dose (ED) of radiation was calculated and compared. Data were analyzed by using Independent samples t test. RESULTS Images of Wide-detector group showed significant lower noise and AI than that of standard-detector group in medulla oblongata (noise:4.96±0.74 vs 5.69±1.03, AI: 3.83±0.93 vs 4.73±1.22) , cerebellar (noise: 4.92±0.67 vs 6.51±1.26, AI: 3.79±0.81 vs 5.69±1.36), pons (noise: 4.86±0.75 vs 5.83±1.03, AI: 3.71±0.90 vs 4.89±1.18)and the inferior part of frontal lobes (noise: 5.19±1.98 vs 6.33±1.22, AI: 4.08±2.15 vs 5.48±1.36) (P < 0.05, respectively), whereas there had no significant difference between two groups in subjective IQ, CNR and SNR (P>0.05, respectively). Compared with standard-detector group, the ED reduction in wide-detector group was 17.37% (1.31mSv±0.00 vs 1.59mSv±0.00, P < 0.05). CONCLUSION Compared to the standard-detector cranial CT scan protocol, the wide-detector (Axial 8cm) mode could provide lower image noise .less BHA and reduced radiation dose.