Equipment

IVIS® Optical System

Kinetic.jpg

The IVIS Kinetic optical imaging system is a real time imaging system enabling acquisition of biologically relevant events within milliseconds. This IVIS systems can be used for in-vivo, ex-vivo, and in-vitro imaging studies and are ideal for both high SNR quantitative scans and high throughput screening applications. The IVIS Lumina optical imaging system is similar to the Kinetic but does not have real time capabilities. The Lumina is located in the Genetic Medicine Building room UB61. The purpose of this machine is to facilitate optical imaging studies with animals located in the GMB vivarium that cannot be returned from outside laboratories.

Study examples

  • Oncology Research
  • Infectious Disease
  • Inflammation
  • Metabolic Disease
  • Neurology
  • Gene Therapy
  • Stem cell Biology
  • Cardiovascular Disease
  • Drug metablism
  • Cherenkov radiation imaging

Main advantages of this system include:

  • Highly sensitive EMCCD camera for in vivo and in vitro imaging of fluorescence and bioluminescence
  • Rapid image readout speeds with frame transfer technology
  • Light-tight injection port, supporting a syringe injector system for real time compound and/or substrate administration
  • Adjustable field of view 5 cm2 -12.5 cm2
  • Highly sensitive EMCCD camera
  • CCD camera is thermoelectrically cooled to -80 C for low dark current and low noise
  • 10 position excitation filters
  • 25 emission filters ranging from 500nm-800nm
  • Fast frame rate for real time imaging

Sample Images (click to enlarge):

Kinetic_Samples1_Icon.jpg Kinetic_Samples2_Icon.jpg

The Ami HT Optical Imaging System: New Features and Comparisons to the IVIS System

AMI HT Small

Figure-1. Ami HT optical imaging system

We recently acquired a new optical imaging system, the Ami HT system (Spectral Instruments Imaging, Inc.), with the funding support from the Lineberger Cancer Center. The Ami system, shown in Figure-1, is capable of providing both bioluminescence and fluorescence imaging on animals and tissue specimens for preclinical research. The system is housed in Marsico Hall, room SB223, within the BRIC Small Animal Imaging Facility. Together with the IVIS-Kinetic and IVIS-Lumina systems, the new Ami system will provide more optical imaging support, and facilitate research projects in our community.

Main Features and Technical Specifications:

The Ami system is very similar to the IVIS –Kinetic system in terms of system structure and operation. However, there are several unique features including:

Large field of view

  • Defalt 25 x17 cm field of view
  • Can image five mice without demagnification lens

Wavelength specific LED excitation light source for fluorescence imaging

  • Individual LED for each wavelength
  • Adjustable power level to meet varius excitation needs

Vertically opening door with more efficency

  • Less isoflurane leakage
  • Easier to use and more robust

Aura imaging software with unlimited seat licenses (downloadable online)

  • Analysis can be done on any 64bit Windows computer
  • Ability to analyze IVIS Living Image files
Table-1: System specifications of Ami and IVIS models
Parameters IVIS-Kinetic IVIS-Lumina Ami-HT
Camera Sensor Back-thinned, back-illuminated, cooled EMCCD Back-thinned, back-illuminated, cooled CCD Back-thinned, back-illuminated, cooled CCD
CCD Size 13 x 13 mm 13 x 13 mm 25.9 x 17.3 mm
CCD Operating temp. at -80°C at -90°C at -90°C
Quantum Efficiency >85% at 500 – 700 nm >85% 500 – 700 nm >85% 500 – 700 nm
Imaging Pixels 1024 x 1024 1024 x 1024 2048 x 2048
Minimal Pixel Size 50 microns 50 microns 22.5 microns
Minimum Detectable Radiance 100 photons/s/sr/cm2 100 photons/s/sr/cm2 45 photons/s/sr/cm2
Field of View (FOV) Min: 5 x 5 cm; Max: 12.5 x 12.5 cm Min: 5 x 5 cm; Max: 12.5 x 12.5 cm Min: 10 x 7 cm

Max: 25 x 17 cm

Dark Current (Typical) < 3 x 10-4 electrons/s/pixel < 3 x 10-4 electrons/s/pixel < 0.9 x 10-4 electrons/s/pixel
Fluorescence Excitation Filters 10 high resolution filters 10 high resolution filters 10 high resolution LED

wavelength specific LED

Fluorescence Emission Filters 18 high-end and 4 standard filters available 4 Standard filters 10 high-end filters integral to system

Performance comparisons to the IVIS-Kinetic system:

The core has conducted a series of evaluations on the new system with a calibration phantom. The results are presented below. To download our comparison in PDF format click here.

1) Photon quantification

A calibration phantom with stable photon emitting source was measured in the Ami and IVIS-Kinetic system. The photon measurements from the two systems were comparable, however, approximately 3.2% more photon was detected per area in Ami system compared to IVIS-Kinetic system, indicating higher sensitivity from the new Ami system. It is recommended that users start the Ami system for a new study. If users want to switch systems in the middle of the study, it is highly recommended that some evaluation studies be conducted before switching. Please contact the SAI staff if you wish to do your evaluation studies before switching.

Ami Kinetic % Difference
Radiance

(x 108 photons/sec)

9.16 ± 0.03 8.48 ± 0.02 7.7 %
Mean Radiance

(x 108 photons/sec/cm2)

2.92 ± 0.01 2.83 ± 0.01 3.2 %
Imaging parameter: Exp. Time=10s; Binning=2; F/stop=Maximum; FOV=Maximum; 5 repeated imaging

Calibration phamtom for AMI HT

Figure-2. Image example with the calibration phantom taken from Ami system

2) Camera signal/counts response

With the same imaging acquisition parameters (exposure time, binning, and aperture size), mean signal in counts/s was measured on the same calibration phantom from Ami and IVIS-Kinetic system. Ami system responded much higher counts/s (about 5.7 times high) compared to IVIS-Kinetic, indicating much higher quantum efficiency, and thus higher sensitivity for the Ami system. This means that imaging on weak bioluminescence signal might make big differences between the two systems, although imaging on high signal would be more comparable (See the comparison in #1)).

Exposure Time Ami Kinetic Ratio
Mean Signal (Counts/s) 0.5 Sec 1991.0 355.2 5.7
10 Sec 37935.4 6651.8 5.7
Other imaging parameters: Binning=2; F/Stop =Maximum; FOV=Maximum

3) Signal to background contrast

Both phantom signal and background signal was measured. The Signal-to-background ratio was compared between the Ami and IVIS-Kinetic system. The Ami demonstrated much higher signal-to-background contrast (about 3.8 times higher) compared to that of IVIS Kinetic, consistently suggesting higher sensitivity in the Ami system.

Ami Kinetic
Phantom (mean counts) 37780 6803
Background (mean counts) 1.809 1.24
Signal-Background Ratio 20884 5486
Difference

3.8 x higher in Ami

4) Fluorescence exitation, emission filters

The Ami and IVIS-Kinetic systems have the same excitation filter sets for fluorescence imaging, but the emission filters are different. Ami has total of 10 emission filters, while IVIS-Kinetic has 21 narrow emission filters, plus another 4 broad band emission filters. Filter sets for each system are listed below.

Ami

IVIS-Kinetic

Emission Filters (nm)

Ten Filters

Low

Mid-high

High

530

500

640

720

590

520

660

740

630

540

680

760

650

560

700

780

690

580

720

800

710

600

740

820

730

620

760

840

750

770

790

Excitation Filters (nm) 430, 465, 500, 535, 570, 605, 640, 675, 710, and 745

**Click here to find out wavelength information for some common fluorophores.**