Method for improving the spatial resolution of narrow x-ray beam-based x-ray luminescence computed tomography imaging

Abstract

Method for improving the spatial resolution of narrow x-ray beam-based x-ray luminescence computed tomography imaging," J.Abstract. X-ray luminescence computed tomography (XLCT) is an emerging hybrid imaging modality which has the potential for achieving both high sensitivity and spatial resolution simultaneously. For the narrow x-ray beam-based XLCT imaging, based on previous work, a spatial resolution of about double the x-ray beam size can be achieved using a translate/rotate scanning scheme, taking step sizes equal to the x-ray beam width. To break the current spatial resolution limit, we propose a scanning strategy achieved by reducing the scanning step size to be smaller than the x-ray beam size. We performed four sets of numerical simulations and a phantom experiment using cylindrical phantoms and have demonstrated that our proposed scanning method can greatly improve the XLCT-reconstructed image quality compared with the traditional scanning approach. In our simulations, by using a fixed x-ray beam size of 0.8 mm, we were able to successfully reconstruct six embedded targets as small as 0.5 mm in diameter and with the same edge-to-edge distances by using a scanning step as small as 0.2 mm which is a 1.6 times improvement in the spatial resolution compared with the traditional approach. Lastly, the phantom experiment further demonstrated the efficacy of our proposed method in improving the XLCT image quality, with all image quality metrics improving as the step size decreased. © The Authors.Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

Focused X-ray Luminescence Computed Tomography using a Continuous Scanning Scheme

“…In this work, we have proposed and investigated a continuous scanning strategy for narrow x-ray beam based XLCT imaging to improve upon the long imaging time. Compared with our previous studies, here we were able to perform a 6-projection transverse scan in 82 secs including all stage movements compared with 292.8 secs as in [11] (also including stage movements), an approximately 3.5 times reduction in scan time. Moreover, we were able to maintain the high-spatial resolution capabilities of this method and were able to successfully separate both targets with an EtE distance of 0.2 mm for all four cases while maintaining a good DICE similarity coefficient for all reconstructions as seen in Figs.…”

Focused x-ray luminescence computed tomography: experimental studies

“…Recently, we have found that the spatial resolution of FXLT can be improved further by reducing the scanning step size as shown by our numerical simulations. Thus, we expect the designed FXLT imaging system may achieve a spatial resolution of 94 μm with 1.6 times improvement by using a scanning step size of 18.5 μm which is a quarter of the beam size as suggested by our recent paper (14).…”

“…Recently, we have found that the spatial resolution of FXLT imaging can be further improved by reducing the scanning step size. All the details of this method have been reported in (14). Here, we briefly describe a set of numerical simulations to demonstrate the efficacy of our proposed method.…”

“…To obtain the high spatial resolution imaging for deep targets, we have focused on the superfine x-ray beam based XLCT imaging (11). Recently, we have found that the spatial resolution of FXLT can be improved further by reducing the scanning step size (14). Here, we have summarized the results briefly.…”

Focused x-ray luminescence imaging system for small animals based on a rotary gantry

“…First, the new scanner’s x-ray beam diameter is much smaller than the previous scanner (49.9 versus ), which will allow for higher spatial resolution capabilities. From our previous reports, 5 , 27 , 28 we can estimate the spatial resolution of the designed FXLT scanner to be about . Next, the use of four highly sensitive PMTs (H7422-50) to detect the emitted optical signals will allow for much more sensitive setup than previously where only one PMT was used.…”