HRA 2 introduction

© Heidelberg Engineering GmbH

Heidelberg, Germany

www.HeidelbergEngineering.com

Heidelberg Retina Angiograph 2

Confocal Digital High resolution High sensitive High contrast Dynamic, simultaneous

fluorescein and indocyanine green angiography system

Confocal Laser Scanning System

LaserLaser

Detector

Diaphragm

BeamBeamsplittersplitter

x-y-z unitx-y-z unit

LensLens Focal planeFocal plane

LaserLaser

Detector

Diaphragm

BeamBeamsplittersplitter

x-y-z unitx-y-z unit

LensLens Focal planeFocal plane

Confocal Laser Scanning System

HRA 2 Camera Head

Laser Sources HRA 2 vs. HRA/C

HRA/CArgon Laser

andCamera Power Supply

Laser Sources HRA 2 vs. HRA/C

HRA/CArgon Laser

andCamera Power Supply

HRA 2OPSL Laser

withCamera Power Supply

Angiography

Fluorescence dyes stimulation with light of specific wavelength,

fluorescence light emission

Fluorescein Excitation/Emission: visible light (488/530 nm)

Indocyanine green (ICG) Excitation/Emission: infrared light (790/830

nm)

HRA 2 Imaging Modes

Fluorescein Angiography (FA) and AF Indocyanine Green Angiography (ICGA) Red Free (Blue Reflectance) Image (RF) Infra-red Reflectance Image (IR) Simultaneous FA + ICGA Simultaneous FA + IR Simultaneous ICGA + IR

Heidelberg Retina Angiograph

Laser scanning system: Low light exposure Continuous imaging Digital images Simultaneous FA/ICGA

Confocal optical system: High image contrast Three-dimensional information

High sensitivity and efficiency: Late phase images

Low Light Exposure

Fluorescence dye is excited in a narrow wavelength band Laser line is most efficient for excitation

Laser scanning system does not require a two-dimensional detector High sensitive ‘point’-detector

Retinal light exposure only 1% of exposure required with photographic systems

Heidelberg Retina Angiograph

Laser scanning system: Low light exposure Continuous imaging Digital images Simultaneous FA/ICGA

Confocal optical system: High image contrast Three-dimensional information

High sensitivity and efficiency: Late phase images

Continuous Imaging

Continuous imaging allows to study dynamic processes blood flow

Special importance in the early phase of angiograms

Heidelberg Retina Angiograph

Laser scanning system: Low light exposure Continuous imaging Digital images Simultaneous FA/ICGA

Confocal optical system: High image contrast Three-dimensional information

High sensitivity and efficiency: Late phase images

Digital Images

Digital instead of analog image acquisition and storage

Digital images offer all capabilities for image enhancement and image processing

Heidelberg Retina Angiograph

Laser scanning system: Low light exposure Continuous imaging Digital images Simultaneous FA/ICGA

Confocal optical system: High image contrast Three-dimensional information

High sensitivity and efficiency: Late phase images

Simultaneous FA and ICGA

Heidelberg Retina Angiograph

Laser scanning system: Low light exposure Continuous imaging Digital images Simultaneous FA/ICGA

Confocal optical system: High image contrast Three-dimensional information

High sensitivity and efficiency: Late phase images

Image Contrast

Heidelberg Retina Angiograph

Laser scanning system: Low light exposure Continuous imaging Digital images Simultaneous FA/ICGA

Confocal optical system: High image contrast Three-dimensional information

High sensitivity and efficiency: Late phase images

Three-Dimensional Angiograms

Heidelberg Retina Angiograph

Laser scanning system: Low light exposure Continuous imaging Digital images Simultaneous FA/ICGA

Confocal optical system: High image contrast Three-dimensional information

High sensitivity and efficiency: Late phase images

High Quality Late Phase Images

Comparison HRA 2 vs. HRA/CHRA/C HRA 2

field of view [degrees] 10x10, 20x20, 30x30 15x15, 20x20, 30x30

image size [pixels] 256x256 (std. res.)512x512 (high res.)

384x384 (15°)

(768x786) 512x512 (20°)

(1024x1024) 768x768 (30°)

(1536x1536)

pixel resolution [µm/pixel] 10, 20, 30 (std. res.) 5, 10, 15 (high res.)

10 (5)

image size [pixels]simultaneous modes

2x256x256 2x384x384 (15°)2x512x512 (20°)2x768x768 (30°)

max .image frequency [frames/sec]

20 (std. res.)13 (high res.)

16 (~8) (15°) 13 (~6) (20°) 9 (~4) (30°)

Line scan frequency 8 kHz (high res)

HRA 2 Laser Sources

FA: optically pumped solid state laser (OPSL), 488 nm

RF: same as FA

ICGA: diode laser, 790 nm IR: diode laser, 820 nm

OPSL

HRA 2 Angiography Characteristics

FA Excitation wavelength: 488 nm, 0.2 mW/cm2

Blocking of excitation light: 1 · 10-6

50 % transmission at: 499 nm Emission detection efficiency: 85 %

ICGA Excitation wavelength: 790 nm, 2.0 mW/cm2

Blocking of excitation light: 3 · 10-6

50 % transmission at: 817 nm Emission detection efficiency: 66 %

Comparison HRA 2 vs. HRA/C

HRA/C HRA 2

laser source, FA argon ion, 488 nm OPSL, 488 nm

laser source, ICGA diode, 790 nm diode, 790 nm

fixation target external (fellow eye) internal array of 3x3 targets, and external

Laser/488 EyeNaFl

Filter/500488 nm

530 nm

Detector

Laser/ 488488

HRA2: Fluorescein Angiography

Laser/790 EyeICG

Filter/810790 nm

830 nm

Detector

Laser/830830 nm

HRA: ICG Angiography

intensity

wavelength800 nm 830 nm

max.excitation

max.emission

excitation emission

ICG Excitation and Emission

intensity

wavelength790 nm 810 nm

excitationwavelength

filteredge

useful emission (>60%)

HRA: ICG Excitation and Efficiency

HRA 2 Acquisition Modes

Single images “Unlimited” number of images

Temporal image sequence Up to 100 seconds of digital video (512 MB) Variable frame rate up to 16 Hz

3D confocal image sequence Variable scan depth up to 8 mm 8 images / mm depth

HRA 2 Acquisition Modes

Stereo image pair Mean image sequence

Adjustable number of images Automatic computation of mean

Composite image sequence Guided by internal grid of 3 x 3 fixation lights Creates 60° x 60 ° image

HRA 2 Internal Fixation Targets

Acquisition of nine 30° images

at 3 x 3 fixation target positions

creates 60° x 60° mosaic image

15°

30°

HRA 2 Internal Fixation Targets

Acquisition of nine 30° images

at 3 x 3 fixation target positions

creates 60° x 60° mosaic image

60°

60°

HRA 2 µP Controlled

Camera, Touch Panel, Laser, Power Supply, Computer: Integrated byµP network

[HRA 2 Camera Control Electronics]

Sapphire Laser

Computer

Frame Grabber [FireWire / USB 2.0]

RS 232 [FireWire / USB 2.0]

HRA II Camera Head

Camera Mount

Power Supply

µC

data l/r

Operation Panel

power

image data

safety

µC

µC

power

HRA 2 Communication

HRA 2 Touch Screen Panel Operation

HRA 2 Touch Screen Panel Operation

HRA 2 Touch Screen Panel Operation

HRA 2 Touch Screen Panel Operation

HRA 2 Touch Screen Panel Operation

Fluorescein Angiography 30°

Simultaneous FA / ICGA 30°

Questions ?