SPECT (Single Photon Emission Computed Tomography)

SPECT is a imaging technique that uses a gamma camera to take multiple views of a patient that has been administered a radionucliede tracer. Tomographic  reconstruction techniques are then used to provide 3D information on the distribution of the tracer. This functional data can be used in a wide variety of medical diagnoses and studies.

Traditionally, the gamma cameras used in SPECT were based on the Anger camera: a slab of NaI(Tl) scintillator coupled to a hexagonal array of PMT detectors. High performance SiPM sensors are now widely available that overcome many of the limitations of PMTs, e.g. low bias voltage, compact and rugged, and with higher detection efficiencies. In particular, SiPM sensors from SensL have the additional advantage of market-leading uniformity, and the highest fill-factor package for creating close-packed arrays. These factors combined allow for a SPECT system with the highest spatial and energy resolution and highest uniformity, allowing for a simpler calibration.

This page gives details of recommended products, some related academic papers and some SensL tech notes that may aid a user interested in SPECT applications.

Recommended Products for SPECT

J-Series sensors have the highest PDE (>50% @ 420nm) allowing efficient detection of scintillation photons even at low gamma energies. The TSV package has the highest packaging fraction of any SiPM package on the market, and as such creates high fill factor arrays for efficient coverage of the area to be imaged.
C-Series SiPM have excellent PDE matched to the most commonly-used scintillators, and have an ultra low dark count rate, which aids detection of the lowest possible energies. C-Series arrays are also available.

Helpful Documents

Building Arrays of SensL SMT Sensors (Tech Note)

This Tech Note has advice for users who wish to create close-packed arrays of MLP or TSV packaged sensors on PCB.

Readout Methods for Arrays of SiPM (Tech Note)

This Tech Note discusses the various readout methods for arrays of sensors, specifically with regard to medical imaging applications.

Signal Driven Multiplexing (Tech Note)

This Tech Note describes in detail and signal multiplexing technique that is used to reduce the number of readout channels for an array.

How to Evaluate and Compare SiPM (White Paper)


This white paper highlights some of the things to consider when selecting an SiPM sensor.