Quantitative PET (QPET)

Overview

Quantitative PET (QPET) is an interactive stand-alone application for the automatic segmentation, quantification and analysis of static and gated myocardial perfusion PET, with support for both short axis and transverse datasets.

Features

  • PET Perfusion Databases

This module allows normal-limit based quantification of Rb-82 and N-13-ammonia perfusion PET images using databases created from scans of low-likelihood patients. Segmental stress and rest perfusion scores can be obtained using the 17- or 20- segment models. Attenuation corrected PET/CT Rb-82 and N-13-ammonia normal limits are provided with QPET. These normal PET/CT databases have separate stress and rest files and combine data from both genders (no differences after attenuation correction).

  • Transverse Datasets Processing

QPET includes native support for PET transverse data. The QPS and QGS contour algorithms have been optimized specifically for transverse PET data, providing a more reliable approach to identifying the heart and valve plane. This also includes an enhanced manual mode allowing reorienting of the transverse data. Once transverse data has been processed, it can be instantly reoriented (obliqued) to standard short axis views, providing the interpreting physician a familiar view of the data. When SPECT images are loaded (even if QPET is enabled), QPS and QGS automatically recognize this and continue with the classic algorithms.

  • Viability Quantification

This module performs the quantitative assessment of "hibernating myocardium" by calculation of relative regional changes between perfusion and viability in areas hypo-perfused on rest. Scar and mismatch parameters are reported as a percentage of the left ventricle. Extent and severity of scar and mismatch can be displayed in polar map coordinates or as a 3D surface display. The program allows automatic scoring of scar using the 17- or 20-segment model. Simultaneous display of stress, rest and viability quantification results is possible. Stress images are not required for the quantification of scar and mismatch.

Optional Feature

QPET - Function

  • Automatic generation of left ventricle (LV) inner and outer surfaces and valve plane from three- or four- dimensional (respectively static or gated) LV short axis perfusion PET data, using user-supplied hints if available (e.g. approximate LV location).
  • Display of projection (raw) images in static and cine mode. Two-dimensional display of gated short axis PET images in 1 (single), 2 (dual), 3 (triple), or 4 (quadruple) mode. (2, 3, and 4 are displayed as interleaved or side-by-side). Three-dimensional parametric display of gated short axis PET images in 1 (single), 2 (dual), 3 (triple), or 4 (quadruple) mode. (2, 3, and 4 are displayed as interleaved or side-by-side)
  • Computation of functional metrics including LV volume/time curve, ED (end diastolic) volume, ES (end systolic) volume, SV (stroke volume), EF (ejection fraction), mid-myocardial surface area, SMS (summed motion score), STS (summed thickening score), SM% (summed motion percent), and ST% (summed thickening percent).
  • Automatic generation of surfaces and polar maps, which display in parametric fashion the pattern of motion and thickening of the LV.
  • Determination and display of the severity and extent of motion and thickening abnormalities using normal limits.
  • Automatic generation of the segmental motion and thickening scores based on a multi-segment, multiple-point scale, and subsequent derivation of the global scores SMS (summed motion score), STS (summed thickening score), SM% (summed motion percent), and ST% (summed thickening percent) from corresponding segmental scores.
  • Computation of diastolic function metrics including PER (peak emptying rate), PFR (peak filling rate), PFR2 (secondary peak filling rate), MFR/3 (mean filling rate over the first third of the ES to ED phase), and TTPF (time to peak filling from ES). BPM (heart beats per minute) is also displayed if available.
  • Display of screen captures and static projection datasets.
  • Storage of all generated results in a separate review file.
  • Integration of ARG (Automated Report Generator) to provide day-to-day reporting functionality.

QPET - Perfusion

  • Automatic generation of left ventricle (LV) inner and outer surfaces and valve plane from LV short axis perfusion PET data, using user supplied hints if available (e.g. approximate LV location).
  • Display of stress and rest projection (raw) images in static and cine mode. Two-dimensional display of stress and rest short axis PET images in 1 (single), 2 (dual), 3 (triple), or 4 (quadruple) mode. (2, 3, and 4 are displayed as interleaved or side-by-side). Three-dimensional parametric display of stress and rest short axis PET images in 1 (single), 2 (dual), 3 (triple), or 4 (quadruple) mode. (2, 3, and 4 are displayed as interleaved or side-by-side).
  • Automatic computation of functional metrics including LV chamber volume and mid-myocardial surface area
  • Automatic generation of stress, rest and reversibility surfaces and polar maps, which display in parametric fashion the pattern of LV myocardial perfusion. Determination and display of the severity and extent of perfusion defects using isotope- and gender-specific normal limits.
  • Automatic computation of global quantitative defect size, both in absolute terms and as a percentage of the mid-myocardial surface area.
  • Automatic generation of segmental perfusion scores (stress, rest and reversibility) based on a multi-segment, multiple-point scale, and subsequent derivation of the global scores SSS (summed stress score), SRS (summed rest score), SDS (summed difference score), SS% (summed stress percent), SR% (summed rest percent), and SD% (summed difference percent).
  • Computation of diastolic function metrics including PER (peak emptying rate), PFR (peak filling rate), PFR2 (secondary peak filling rate), MFR/3 (mean filling rate over the first third of the ES to ED phase), and TTPF (time to peak filling from ES). BPM (heart beats per minute) is also displayed if available.
  • Display of screen captures images (also known as snapshots).
  • Storage of all generated results in a separate review file.
  • Integration of ARG (Automated Report Generator) to provide day-to-day reporting functionality.

Screenshots

Software Availability

Information regarding the availability of QPET can be found here.

Publications

  • PET Perfusion Databases: Slomka PJ et al. Automated quantification of myocardial perfusion SPECT using simplified normal limits. J Nucl Cardiol 2005;12:66-77.
  • Viability Quantification: Beanlands R et al. Positron Emission Tomography and Recovery Following Revascularization: The Importance of Scar and the Development of a Prediction Rule for the Degree of Recovery of Left Ventricular Function. J Am Coll Cardio 2002;40:1735-43.
  • Viability Quantification: Slomka PJ et al. Automatic volumetric quantification of mismatch and scar from cardiac PET by image registration. J Nucl Cardiol 2004;11(3):369.
  • Slomka PJ et al. Comparison of clinical tools for measurements of regional stress and rest myocardial blood flow assessed with 13N-Ammonia PET/CT. J Nucl Med 2012; 53:171-181.