Gantry Rotation speed

MDCT technology continues to evolve rapidly. At the current stage of development, improvements concentrate on gantry rotational speed (up to 270 ms for a... 

Flohr T, Bruder H, Stierstorfer K, Simon J, Schaller S, Oh-nesorge B (2002a) New technical developments in multislice CT, part 2 sub-millimeter 16-slice scanning and increased gantry rotation speed for cardiac imaging. Rofo 174 1022-1027... 

Residual cardiac motion should be completely absent when performing coronary CTA for stent evaluation. While residual motion negatively affects all coronary CT exams, metal-related artifacts are especially increased. BCG gating, gantry rotation speed, heart rate, etc., apply as for all cardiac CT exams. 

Helical pitch <1 ( high-speed helical techniques produce unacceptable reconstruction artifacts in the posterior fossa) Slow table speed (8-11 mm/s) Rapid gantry rotation (0.5-0.8 rotations/s) Smallest possible focal spot setting ... 

A SPECT system consists of one or more scintillation cameras mounted to a gantry that can revolve about a fixed horizontal axis (the axis of rotation) " (Fig. 27.13). SPECT studies are usually acquired over a full 360° arc, although myocardial perfusion studies typically use only data from the 180° arc that minimizes tissue attenuation. SPECT acquisitions are performed with the scintillation camera located at preselected angular locations (step-and-shoot mode), or in a continuous rotation mode. In the step-and-shoot mode, the detector rotates to each angular position and collects data in a preselected frame duration while the detector is motionless. In the continuous-rotation mode, the smdy duration is selected and the rotation speed is adjusted to complete the orbit during this time. Projections are collected as the detector rotates and are binned into 60 to 120 frames over 360°. 

The robots may apply dots, lines, at high speeds and very accurately. There are also rotary dispensing systems, with rotary tables which are convenient for dispensing circular patterns. They are adjustable in rotation speed, circles, diameters and dispensing time. They dispense from barrels, cartridges or valves mounted on the Z axis gantry. Figures 88 to 90 show several applications in electronics, Hifi and other industries. 

Spiral/hehcal scanning is characterized by continuous gantry rotation and continuous data acquisition while the patient table is moving at constant speed see Fig. 1.7. 

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