Patent ID: 7511277

Claim:
A nuclear medicine diagnostic apparatus with detector units arranged around a bed on which to hold a human body examined, the detector units each comprising: a plurality of unit substrates each including a plurality of radiation detectors for detecting radiation, and a plurality of signal processors to each of which an independent detection signal from each of the radiation detectors is input; a housing member having the plurality of unit substrates, the housing member being segmented into a first region in which the plurality of radiation detectors are disposed, and a second region in which the plurality of signal processors are disposed; and means for first introducing a gaseous coolant into only the second region through a ventilation hole in order to cool the plurality of signal processors, and then discharging the coolant from the second region; wherein the housing member is formed with a ventilation port to communicate with an exterior of the housing member as well as with the first region, the housing member also having an anti-dust filter connected to the ventilation port.