Construction Of Digitized Histological Atlas Of Basal Ganglia In Human Brain

The basal ganglia area which have complex structures and functions lie in deep brainand form integral parts of movement and emotion control loop. Identification ofmorphology and loaction of different nuclei and function divisions of deep brain structuresin patients is crucial for the stereotactic operation which often demands a histological levelof resolution. However, the current MRI and CT can’t accurately identify the boundaries ofnuclei and function divisions, due to the lack of histological information. In this study,histological method and digitized technology were used to collect basal ganglia data. Basalganglia tissue block was extracted from a cadaver with no neurological disease, and wascryosectioned at60-μm-thickness in coronal section and the sectional images were capturedsimultaneously by a digital camera, at fixed position. One seires of sections(every tenthsection) was Nissl-stained with Toluidine blue, another series was immunostained for thecalbindin D-28K. Stained sections were digitized by a high resolution scanner. Afteralignment and registration,contours of nuclei and different function divisions in nuclei wereidentified, and then segmented and labelled on the digital images of stained sections. Withthe help of image registration software, the contours of nuclei and function divisions weredeformed onto MRI of patients. Three-dimensional models of nuclei and function divisionswere reconstructed and the anatomic parameters of nuclei and function divisions in standardbrain stereotactic space were calculated as well.The main results demonstrated in thepresent study are as following:1. Volume rendering model of head in CVH2was regard as a reference to obtain tissueblock of basal ganglia from brain and the cut tissue block was4cm×5cm×6cm.Visualization technique and equipments were improved and used to obtain cross-sectionalimages of the basal ganglia, and a systematic method of large tissue block cutting, slicing,staining and data acquistion were established.2. Tissure block was cut into60μm on a freezing microtome and cross-sectional images were taken every sections. The resolution of images reached to3072×2048pixelsand the file of each image occupied7MB. With Nissl and calbindin D-28K staining, oneseries of Nissl-stained sections and another series of calbindin D-28K stained sections wereobtained, and then digitized by high resolution scanner.3. After alignment and registration, the distortion of stained-section images wascorrected. A series of cross-sectional images data set and two series of stained sections datasets were obtained.4. Semi-automated segmentation and Photoshop software were selected to segment thenuclei of striatum, thalamus and midbrain on Nissl-stained sections images. The functiondivisions of caudate nucleus, putamen, lateral and medial globus pallidus were segmentedon calbindin D-28K stained sections images.5. The contours of nuclei and function divisions were deformed onto MRI of patients,as a reference of nuclei identification.6. The segmented structures were reconstructed in three-dimensions with surfacerendering reconstruction of Amira software.The reconstructed structures can be displayedsingly or as a whole and can be rotated in three-dimensional space.Three-dimensionalcoordinate system was established on the midpoint of AC-PC. The data about centercoordinates, coordinates ranges and volumes of basal ganglia nuclei and functionaldivisions was obtained from three-dimensional models, which could be applied in clinic asreferences of stereotactic operation.