OCT-based Neuro-Imaging

Project Description

Optical Coherence Tomography (OCT) is a relatively young imaging technique. Based on the principle of interferometry, its functionality resembles the principle of ultrasound. In OCT imaging, however, near-infrared light with a wavelenght of 800 to 1500 nm is used which is scattered by the examined sample. The advantages of OCT imaging is the high resolution (1 – 10 mm), real-time capability, and the atraumatic imaging (no direct contact to the sample is needed). Disadvantage is the small imaging depth of 2-3 mm. OCT has been used in many medical applications, major developments have been made in the field of ophthalmology, dermatology, and urology. Little work has been done in the field brain imaging with OCT. It has been shown that tissue structure in vitro can be displayed by OCT (e.g. grey and white matter) and that tumorous tissue can be reliably identified.

From this state of the art, different research topics arise:

OCT for brain imaging

Despite the advantages of OCT, no explicit integration of OCT into the neurosurgical setup such as neuroimaging and neuronavigation has been done. As OCT could be integrated into minimal-invasive instruments, this kind of applications would be supported. Such an integration would for example allow for a real-time validation of the planned path. Several goals are focused on: development of a minimal-invasive probe for neuroimaging of the deep brain, development of brain tissue classification algorithms, and integration into the neuronavigation.

Speckle reduction in OCT images

As ultrasound images, OCT images are subject to speckle noise. Although speckle contains an information carrying part, this kind of noise often distorts the image and complicate subsequent use for diagnosis. In this project, new methods of speckle noise reduction are to be developed. This will be done based on two approaches:

(a) development of novel image processing methods and
(b) modified imaging modalities.

Tissue structure identification in OCT images

Closely related to the speckle noise reduction is the task of information extraction in OCT images. For diagnostic purposes (such as layer identification in the retina), the extraction of tissue structures is often of major interest. This project aims at the development of novel tissue structure identification methods in OCT images supporting the diagnosis or the orienation of the surgeon.

Publications

Contact Person

Achim Schweikard
Bldg 64 / Room 97 +49 451 31015200


Floris Ernst
Bldg 64 / Room 95 +49 451 31015208


Former project members
  • Dr.-Ing. Lukas Ramrath

2008

Lukas Ramrath, G. Moreno, Heike Mueller, Tim Bonin, Gereon Hüttmann and Achim Schweikard, Towards Multi-Directional OCT for Speckle Noise Reduction, in: MICCAI 2008, Part II, pages 815--823, 2008
[DOI]
[Bib|RIS]

2007

Fernando Gasca and Lukas Ramrath, Model-Based Detection of White Matter in Optical Coherence Tomography Data, in: Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Lyon, France, 2007
[Bib|RIS]
Lukas Ramrath, Ulrich G. Hofmann, Gereon Hüttmann, Andreas Moser and Achim Schweikard, Towards Automated OCT-based Identification of White Brain Matter, in: Bildverarbeitung für die Medizin, 2007
[DOI]
[Bib|RIS]

2006

Lukas Ramrath, H. Fuellgraf, C. Winter, Ulrich G. Hofmann, Gereon Hüttmann, Andreas Moser and Achim Schweikard, 3D Visualization and Identification of Rat Brain Structures using Optical Coherence Tomography, in: 5. Jahrestagung der Dt. Gesellschaft fuer Computer- und Roboterassistierte Chirurgie, Hannover, 2006
[Bib|RIS]