Stereotactic Study And Visualization Of Internal Capsule Based On Thin-section MR Imaging

Background: With the development of stereotactic technique, functional brain imagingtechnique, X-knife, γ-knife technique, minimally invasive surgical technique andmolecular biology of neural technique, the requirement of functional neurosurgery,minimally invasive neurosurgery based stereotactic technique is increasing. A thin layerbrain MRI images of the brain parenchyma region morphology, three-dimensional andthree-dimensional visualization of spatial localization depth and meticulous researchwill show a view of the brain space-occupying lesions in the small precise positioning,and make an accurate plan to preoperative surgery, and provide a proposal forintraoperative surgery.The internal capsule was first proposed by Burdach, is located in the caudate nucleus,lenticular nucleus and thalamus, a white matter plate. In the horizontal section likes"V"-shaped open outwards consist of forelimb, hindlimb and knee. Forelimb (alsoknown as frontal) towards the front outside, between caudate nucleus and lenticularnucleus. Hindlimb (also known as occipital) towards the back outside, divided (betweenlenticular nucleus and thalamus) beans thalamus, the lenticular nucleus lower rear andthe lenticular nucleus underneath. Knee is between the front and the hind limbs, the "V"shaped corner. The capsule is an area of the upstream and downstream fiber throughbetween the cerebral cortex and the subcortical. Total disability in the internal capsulethan other regions of the brain lesions caused more extensive. Meanwhile the internalcapsule in CT and MRI diagnosis has important clinical significance.Domestic and foreign studies of the internal capsule is mainly structural damage anddisfunction, except with regard to the internal capsule simple structure, no overallmorphological studies. Therefore, describe the internal capsule structure in the crosssection in detail, study the non-symmetry, build three-dimensional positioning data setsand3D visualization model of the internal capsule, to providing information foranatomical minimally invasive surgery and medical teaching.Objective：In this study, the midpoint of anterior commissure-posterior commissure isorigin, a total overlap between the diameter and the Y-axis to build a three-dimensionalCartesian coordinate system. Through the research of the thin sac in the30cases ofChinese healthy adult brain MRI image to find the capsule morphology law on cross-section; establish internal capsule three-dimensional positioning data sets andobtain the regression equation in this coordinate system; analyse the capsulenon-symmetry; build the three-dimensional visualization of the internal capsule modelin the entire brain. Provide anatomic basis for stereotactic and functional neurosurgery,stereotactic radiosurgery and minimally invasive surgery and the development of sacstructure and contact function.Methods：1.30healthy adult volunteers brains anterior commissure-posteriorcommissure is scan baseline transverse diameter of2mm thin layer of MRI scans.Microcomputer use Dicom3.0format scan data send into eFilm2.1workstation. Using"3D-Cursor" technique to identify regions within the brain capsule, observe and statisticmorphological characteristics.2.30healthy adult brains MRI transverse layer data export and save as JPG format, andthen import the Photoshop software, strict registrate the image, based on the midpoint ofanterior commissure-posterior commissure of a three-dimensional Cartesian coordinatesystem, X-axis, Y-axis coordinate system coincides with the software itself. Measureand write the recording of the inside border and the outside border of the capsule thecoordinate X values, Y values, Z is the product where the AC-PC distance of thenumber of layers and the thickness of the flat, the coordinate values of all samplingpoints within the three-dimensional composition of the capsule coordinate system tolocate the data set; using data obtained in30cases, complete the projection transverse,sagittal and coronal planes in the SPSS; using SPSS17.0software obtain regressionequation in each projection direction linear.3.EFilm Workstation in the computer is used, select the30cases of normal people,15males and15females, head cross-sectional MRI image, select the aspects of the internalcapsule appeared, import the image into Photoshop software to measure, draw the maleand female left and right sides typical levels distance from the median sagittal plane,obtained layers male and female on both sides of the distance differences by statisticalsoftware SPSS17.0.4.In the micro-computer, five cases of normal adults (no neurological, psychiatrichistory and family history) layer of2mm thin cross-sectional MRI brain scan data sendinto3D-Doctor software of Dicom3.0format, artificial division sac internal capsule,basal ganglia, lateral ventricle and the brain surface were marked with different colors,use the complex structure of the surface reconstruction method for three-dimensionalreconstruction of the above simultaneously. Results：1.Accurately identify the thin sac in the cross-sectional MRI imagecontinuous level, draw the shape and the position of the internal capsule.2.Build normal adult male and female the inner and outer edge of the capsulestereotactic coordinates in three-dimensional data set; projection transverse, sagittal andcoronal planes can reflect the characteristics of the internal capsule; obtain the inner andouter edge of the capsule in each projection straight and curved plane regressionequation.3.Statistics left and right sides differences and gender differences of male and femalesac in the transverse mapping.4.Successfully rebuilt the three-dimensional visualization model of internal capsule,basal ganglia and lateral ventricles in the brain, the model can be rotated in anydirection, from a different angle to reproduce three-dimensional shape of the internalcapsule, the basal ganglia and the lateral ventricles in the brain, the spatial position andthe mutual position relationships.Conclusions：1. Use "3D-Cursor" technology easily identify the coronal plane, youcan accurately identify the thin sac in the cross-sectional MRI image continuous level,provides an anatomy program basis for the development of basal ganglia lesionlocalization and surgical approach. Multifaceted analysis of the internal capsule providea reference for diagnostic imaging, surgical approach and the occurrence of brainscience.2.Construct the internal capsule based on anterior commissure-posterior commissurestereotactic positioning system data sets, analyze projection transverse, sagittal andcoronal plane and the regression equation, provides anatomical basis for stereotactic andfunctional neurosurgery applications; simultaneously to reveal the brain morphologicalrule.3.Male, female left and right sides of the capsule about the mapping relationship in thecross section, can be expressed as the same sex groups on both sides of the internalcapsule are angled "mirror image" to the median sagittal, male is bigger than female onboth sides of the internal capsule in different gender people groups.4. Three-dimensional visualization model within the internal capsule demonstrate thevivo three-dimensional structure of the brain and the adjacent relationships, provides animportant approach for reconstruction and observation of brain lesions, surgicalapproach for the development of stereotactic surgery, interventional radiology and radiation treatment planning.