QUASAR™ GRID³ᴰ Image Distortion Analysis System

The QUASAR™ GRID³ᴰ Image Distortion Analysis System is designed to evaluate MR and CT imaging data on Leksell Gamma Knife® platforms, including PERFEXION™ and ICON™.

Understanding the integrity of your system’s spatial accuracy provides you the confidence of accurate and precise delivery of Gamma Knife stereotactic radiosurgery. Use the valuable data obtained using GRID³ᴰ to optimize imaging sequences and manage image distortion on your planning systems.

“What I like about the QUASAR™ GRID³ᴰ system is the simplicity of its design and operation. In a matter of minutes I can obtain a full 3D distribution of geometric distortion. Fine-tuning an MR sequence is now an efficient undertaking, as opposed to a nearly endless chore of phantom preparation and image analysis.”

Ian Paddick, Consultant Physicist, Medical Physics Limited

  • Specifications

    • Phantom constructed of acrylic with nylon and delrin parts
    • Phantom filled with 2 mM solution of copper sulphate
    • Imaging portion of the phantom is 14 cm (S/I) x 13 cm (A/P) x 11 cm (R/L)
    • Overall dimensions are 19 cm x 22.3 cm x 18.5 cm
    • Weight 4.5 kg
    • User’s Guide
    • Storage Container for special handling
  • Minimum Technical Requirements

    • Standard PC desktop or laptop with Windows 7, Vista or XP
    • Minimum 110 Mbytes hard disk space required for installation – more required for images
    • Minimum 256 MB free RAM
    • Screen resolution minimum 1280 x 1024, recommended 1600 x 1200
  • 100-1017: GRID³ᴰ Image Distortion Analysis System, includes;

    • 1-Phantom
    • 1-Software License
Download Product Data Sheet


Phantom Design

The GRID³ᴰ phantom is a dense acrylic 1 cm x 1 cm x 1 cm grid, encompassing a volume of 11 cm x 13 cm x 14 cm. The lattice structure is a key feature of the phantom design, where 1.5 mm CuSO4 solution filled channels converge, creating 2002 signal-producing control points for detailed data analysis.


Process images and assess image distortion on MR and CT systems used in SRS planning, with or without a Leksell Gamma Knife® fiducial box. Ability to process co-registered datasets with increased support for ICON™ CBCT analysis. Valuable for Image Distortion Analysis on all Leksell Gamma Knife® platforms.

High Resolution Geometric Accuracy

A dense matrix of 1.5 mm signal generating channels create 2002 control points for geometric analysis. The position of all control points is confirmed to be within 0.1 mm manufacturing tolerance resulting in reliable accuracy. The GRID³ᴰ solution provides users with the confidence to make informed decisions on your department’s imaging systems.

Increased Confidence

Included within the transparent data reporting structure is the ability to assess Geometric Distortion within an imported GammaPlan® spatial reference frame. This feature allows correlation of data with the Leksell Gamma Knife® Coordinate System. Confirming your data within a familiar frame of reference increases confidence in GRID³ᴰ results.

Workflow Efficiency

The phantom is designed for simple, reproducible insertion into a Leksell G-frame fiducial box or use within the frameless ICON™ platform. Automated image analysis with an advanced user interface provides efficient image distortion analysis. Customizable interpretation, visualization and reporting features, enable smooth workflow in a clinical setting.


The QUASAR GRID³ᴰ image distortion analysis system includes the high-resolution phantom and robust automated software platform. Together, they establish confidence that the imaging system supports the geometric accuracy and precision of the Leksell Gamma Knife®.

Advanced Control Point Detection

Our proprietary GRID³ᴰ analysis software uses an advanced, automated control point detection algorithm using channel detection methods. This results in a reduction of lost data points and improved detection accuracy. The algorithm is minimally affected by micro air pockets or image artifacts adjacent to measurement control points.

Easy to read data evaluation tools

Improve workflow efficiency by using intuitive software features designed to aid in your image distortion evaluation. Multiple charting and reporting options are at your fingertips to provide the necessary tools to make an informed decision. A report generator produces a PDF of analyzed data in an easy to interpret format.

Individual Control Point Evaluation

Each control point has a calculated geometric distortion and a detection uncertainty. Detected control points can be manually tuned by the user as desired to increase reporting accuracy. The software supports analysis directly within the GammaPlan™ frame of reference to increase user confidence in the resultant GRID³ᴰ DVF.

Enhanced 3D visualization Tools

Advanced interactive statistical graphics allow users to discover, explore, summarize and visualize quantitative data in order to form conclusions and make decisions. A customizable graphic display allows you to analyze the amount of distortion at a specific control point, accompanied by the uncertainty value of its detection.

Product Information & Accessories