Assessment of In-Stent Restenosis Using High-Definition Computed Tomography With a New Gemstone Detector

Abstract

1542TSUDA T et al. Circulation JournalOfficial Journal of the Japanese Circulation Society http://www. j-circ.or.jpMoreover, stents with diameter <3 mm are reported to have lower assessability than those ≥3 mm. 16 As an alternative method, stress tests could be used for non-invasive detection of ISR, but unfortunately the diagnostic accuracy is not so high. Although invasive coronary angiography (ICA) is the most reliable method for assessing ISR, there are disadvantages due to the possible serious complications during the procedure, and high cost. Thus, CTCA is the preferred modality to detect ISR in patients undergoing previous coronary stent implantation because it can visualize the in-stent lumen, non-invasively. Discovery CT 750HD (GE Healthcare Technologies, WI, USA) is a high-definition CT (HDCT) machine with a new gemstone detector (GE Gemstone TM detector). Gemstone is a complex rare earth-based oxide that has a chemically replicated garnet crystal structure, and has a primary speed of only 30 ns (100-fold faster than existing detectors) and low afterglow (4 times lower), which is a key contributor to fast kVP switching acquisition through its scintillator and data ercutaneous coronary intervention with stent implantation reduces restenosis of culprit lesions compared with plain-old balloon angioplasty alone. 1,2 Moreover, drug-eluting stents (DES) have remarkably improved results by preventing excessive neo-intimal hyperplasia of coronary arteries, 3,4 so that they are now widely used for small vessels, long lesions, and those with bifurcations, for example. 5,6 But even in the DES era, lesion complexity or patient comorbidities are related to restenosis. 7 Recently, computed tomography coronary angiography (CTCA) has become established in the non-invasive assessment of coronary stents. Multi-slice computed tomography (MSCT) or multi-detector computed tomography (MDCT) with 64-slice technology has improved the spatial resolution with a sensitivity of 82-95% and a specificity of 82-98% for de novo lesions of the coronary artery. 8, 9 Reports so far have indicated that MSCT or MDCT have a sensitivity of 90-95%, and a specificity of 73-93% for detecting in-stent restenosis (ISR). 10-15 It is sometimes difficult, however, to assess in-stent lumens due to stent strut artifacts. Background: Until now, there have been few reports on the accuracy of in-stent restenosis (ISR) detection using high-definition computed tomography (HDCT). The purpose of this study was to assess ISR using HDCT with a new gemstone detector and to examine the diagnostic accuracy compared with invasive coronary angiography.

Ultra-low-dose lung multidetector computed tomography in children – Approaching 0.2 millisievert

“…The main dose reduction methods are X-ray beam shaping (e.g. tin filtering) [11], detector efficiency improvements [12], Abbreviations: AAPM, The American Association of Physicists in Medicine; AP, anteroposterior; CT, computed tomography; CTDI, computed tomography dose index; DLIR, Deep Learning Image Reconstruction; DLP, dose length product; DRL, diagnostic reference level; Dw, water equivalent diameter; ED, effective dose; HU, Hounsfield unit; IQSC, image quality scoring criteria; kV(p), (peak) kilovoltage; LR, localizer radiograph; mA, milliampere; mAs, milliampere-second; MDCT, Multidetector Computed Tomography; mGy, milligray; ML, mediolateral; mSv, millisievert; ROI, region of interest; SD, standard deviation; SSDE, size specific dose index.…”