3D Reconstruction of Serial Sections
Dr. Brad Duerstock's research interests involve the development of 3D surface reconstructions and volume visualizations of injured segments of spinal cord from serial histological sections. 3D imaging of spinal cord injuries was accomplished using different algorithms that produces either volume visualizations or surface reconstructions. The software algorithms used for 3D surface reconstruction were developed at the Center for Computational Visualization at The University of Texas.
Isocontouring Method
This surface reconstruction method is similar to Surface Tiling but does
not require circumscribing contours by hand. Object selection is
accomplished by discrimination of pixel values. This method alleviates
labor and time costs and user subjectivity.
Below are 3D surface reconstructions of a spinal cord segment and its central grey matter from the lower thoracic level in the rat.
Surface reconstructions not only allow anatomical structures to be viewed
three-dimensionally but also permit surfaces of biological features to
be quantitatively interrogated as well. 3D measurements, such as volume
and surface area, can be precisely calculated for each surface using this
software.
Animations of the interior of a 6
month-old injured spinal cord segment caused by piercing the cord
during ventral implantation of a piece of muscle. The puncture wound
caused
the formation of 3 large cysts in the chronic injury, unlike the pathology
of compression or contusion injuries.
Walk-through the interior of the SCI (1.6MB .QT)
Navigation through the central canal into one of the large cysts (700KB .QT)
Volumetric Texture Imaging
This is a volume rendering of a three week-old compression SCI. The 4
mm-long segment
of rat spinal cord runs lengthwise from top to bottom. In the center is the
injury site shown in bright green which is characterized by intense
labelling of active macrophages. Macrophages or scavenger cells invade the
subacute injury in large numbers. These cells cause holes or cysts within the
nervous tissue.
Rotation of the injured spinal cord (751KB .QT)
Transparency reveals the centralized cysts (1.5MB .QT)
Surface Tiling Method
This is probably the most common method for 3D surface reconstruction.
This type of algorithm "stacks" 2D contours (manual tracings of regions
of interest) per histological section to form a 3D surface of a particular
anatomical structure.
These 2 images show 3D
surfaces of the injury site (blue) superimposed within histological sections
from which they are generated. This is the same spinal cord as shown by
volumetric texture imaging (above).
This method
produces 3D surfaces that are reconstructed
from a series of connected triangles (left). However surface
reconstructions can be textured and made transparent (right) to allow
inspection of internal structures like the grey matter (red). The
ventral side of the uninjured spinal cord segment is facing up.
The set of histological slices used to compose the
blue 3D reconstructed injury site (937KB .QT)
Duerstock, B.S. (2003) Double Labeling Serial Sections to Enhance Three-Dimensional Imaging of Injured Spinal Cord. J Neurosci Methods 134(1): 101-107. Duerstock, B.S., Bajaj, C.L., and Borgens, R.B. (2003) A Comparative Study of the Accuracy of Three-Dimensional Reconstructions of Spinal Cord from Serial Histological Sections. J Microsc-Oxford 210:138-148 Pt 2. Duerstock, B.S., Bajaj, C.L., Pascucci, V., Schikore, D., Lin, K., Borgens, R.B. (2000) Advances in Three-Dimensional Reconstruction of the Experimental Spinal Cord Injury. Comput Med Imag Grap 24(6): 389-406. Moriarty, L.J., Duerstock, B.S., Bajaj, C.L., Lin. K., and Borgens, R.B. (1998) Two- and Three-Dimensional Computer Graphic Evaluation of the Subacute Spinal Cord Injury. J Neurol Sci 155: 121-137.