Dead time losses are not serious in most static imaging studies, but they can be important in certain high-counting-rate applications (e.g., first-pass cardiac studies) in which counting rates as high as 105 cps may occur. Pile-up rejection circuitry (see Chapter 8, Section B.3) is used to achieve higher usable counting rates in such situations. Another approach for shortening camera dead time is by the use of analog buffers, or derandomizers. These are electronic circuits that “hold” a voltage level or pulse from one circuit component (e.g., an amplifier) until the next circuit in the pulse-processing sequence (e.g., the PHA) is ready to receive it.