TY  - CHAP
M1  - Book, Section
TI  - Computed Tomography of the Coronary Arteries
A1  - Nieman, Koen
A2  - Samady, Habib
A2  - Fearon, William F.
A2  - Yeung, Alan C.
A2  - King III, Spencer B.
PY  - 2017
T2  - Interventional Cardiology, 2e
AB  - Computed  tomography  (CT)  was  developed  in  the  early  1970s.  The  first  computed  axial  tomography  (CAT)  scanners  developed  by  Sir  Geoffrey  Hounsfield  and  colleagues  required  long  acquisition  and  reconstruction  times  and  were  only  suited  for  (small)  stationary  body  parts  like  the  head  (Fig.  12-1).  However,  within  the  same  decade,  scanners  dedicated  to  cardiac  imaging  were  developed  that  were  able  to  acquire  images  in  100  milliseconds  or  less,  which  was  sufficient  to  virtually  freeze  cardiac  motion.  Contrary  to  mechanical  CT  scanners,  these  electron-beam  CT  systems  lacked  mechanically  rotating  parts.  Instead  of  a  rotating  tube-detector  unit,  a  beam  of  electrons  was  electromagnetically  swept  along  a  stationary  tungsten  target  ring  around  the  patient.  As  the  electrons  hit  the  tungsten  ring,  a  roentgen  fan  beam  was  created.  On  the  opposite  side  of  the  gantry,  attenuated  roentgen  rays  were  collected  by  a  stationary  ring  of  roentgen  detectors.  For  over  2  decades,  these  scanners  were  in  operation,  primarily  to  image  coronary  calcium,1  but  also  to  image  the  coronary  lumen  after  intravenous  contrast  injection.2  Technical  and  other  practical  challenges  to  electron-beam  CT,  such  as  difficulties  expanding  the  number  of  simultaneously  acquired  slices  and  expanding  the  longitudinal  scan  range,  stalled  further  exploitation.  
SN  - 
PB  - McGraw-Hill Education
CY  - New York, NY
Y2  - 2024/04/24
UR  - accesscardiology.mhmedical.com/content.aspx?aid=1146596028
ER  -