rBV (Autorad): Quantification with one Static Scan

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rBV (Autorad): Quantification with one Static Scan

The rBV ( Autorad) model is intended for the quantitative assessment of the regional blood volume (rBV). The required measurements are a static C15O PET scan and external blood sampling. After a bolus inhalation of C15O inhalation an equilibration period should be allowed for 5 min. Then, blood data are sampled while a static PET acquisition is performed. The rBV can finally be calculated by dividing the PET activity by the integrated blood activity.

Acquisition and Data Requirements

Image Data

A static PET data set representing the equilibrium brain activity during C15O inhalation. If more than one frame has been loaded, the average PET activity is calculated during the pixelwise calculations.

Blood Data

Blood activity sampled at a peripheral artery after equilibration from beginning until the end of the PET acquisition.

Blood Preprocessing

The only available blood preprocessing option is decay correction.

Model Preprocessing

Just reads numerical data needed for pixelwise processing in two input fields.

PXMOD rBV (Autorad) Model Pre-Processing

R

Hematocrit Ratio Small/Large Vessels. Mean ratio: 0.85.

D

Density of brain tissue: 1.05 [g/ml].

Model Configuration

PXMOD rBV (Autorad) Model Parameters

rBV

Regional blood volume in [ml/100g]. It is calculated as:
rBV = PET*100/(R*D*integrated_blood)

Reference

1.Mintun MA, Raichle ME, Martin WR, Herscovitch P: Brain oxygen utilization measured with O-15 radiotracers and positron emission tomography. J Nucl Med 1984, 25(2):177-187.

Note: The main focus of the cited reference is the calculation of regional brain oxygen extraction (CMRO2). That model requires the pixelwise knowledge of the rBV and the rCBF. These functional maps could be determined with models supported in this software. The calculation of the CMRO2, however, is currently not available.