Precentral Gyrus Of Cerebram: Computational Neuroimaging Anatomy And Three-dimensional Visualization

Background: With the adanced develop of the mirconeurosurgical and neuroimaginging technology, contemporary neurosurgery has changed from the traditional classical neural surgery craniotomy to the individual minimally invasive surgical approach, which centers on the lesion, and precisely locating the lesion preoperatively is the basia of the minimally invasive surgery. Since recent years, because of the quickly development of tachoprgress of functional neurosurgery and microneurosurgery on account of stereotaxis technology, we will research intensively sectional imaging anatomy of cortical sulci in cerebral lamellar MRI image to expect it can offer important help for locating tiny occupying lesion in cerebrum precisely.Prencentral gyrus(Pre CG) locate in the amphi- hemicerebrum,from superior of the cerebrum to the inferior until arrivel in lateral sulcus,it also between in the precentral sulcus and postcentral sulcus. Pre CG belong to the part of frontal lobe. Usually Pre CG is connect to superior frontal gyrus, middle frontal gyrus, inferior frontal gyrus in the cross section and also connect to postcentral gyrus in the superior of lateral sulcus.The part of Pre CG reflex to backward and formate knob shape. Central sulcus and postcentral gyrus backward in the same time. This knob is larger than the other of cerebrum. Previous articles described the hand motor cortex(HMC) in dissected brains or on CT or MR imaging as having either the shape of a typical hook, bayonet, step, or zigzag on the sagittal plane. Other authors described this structure as a knuckle or as a structure like an omega on the axial plane. Yousry defined the ―omega‖ as the most reliable landmark for the identification of the precentral gyrus. The characteristic inverted omega(Ω) shape of the HMC in the axial plane was explained by the presence of 2 anteriorly directed small fissures, which stem from the middle genu of the precentral sulcus. Occasionally, the presence of a third fissure, placed between the first 2, confers a characteristic horizontal epsilon(ω) shape.Accordingly, aim directly at above-mentioned, We have done some research and statistical analysis and obtained some conclusions on the basis of the study of male and female 20 cases of heath-adult head MRI. We hope our finding would offer quantized anatomic data for research on developing regularity of this cerebral region, individual and hemispheric variance, relationship berween architecture and function of Pre CG, as well as stereotaxis and microinvasion psychosurgery in this area. Objective: the purpose of this study weire to locate and analyse morphology feature of the HMC. And to research the morphology of precentral gyrus(Pre CG) on MR image, to establish a spatial for in the Descartes coordinate system and obtain the fitting curvilinear equation of the most internal and lateral point of the anterior and posterior of the Pre CG, to reconstruct 3D visualizational model of the PG, which can provide radiologic anatomy information of Pre CG for stereotactic, interventional radiology, microsurgical.Methods: 1.Obtains the structural brain MRI of transection plane, sagittal plane, coronal plane from 96 cerebral hemisphere of 48 right-handed healthy volunteers. Indentify and locate the precentral knob,in the same time, seek and analysis the regular of the morphology.2. 40 cases of the health of ordinary people volunteer brain, male 20 cases, 20 cases of female cross, sagittal and coronal–sectional MRI data which were scanned according the AC-PC line are imported to e Film workstation in the form of Dicom3.0, then morphorlogy character were observed by the technology of the ―three-dimensional coursor‖ and located collateral sulcus in 2mm continuous transverse and coronal MR image and statistics results were acquired.. Male and female cross section layer of 20 healthy adult brain MRI data was imported into Photoshop CS by from transition. Through the strict registration of the image, we can make the coordinate system of the software coincide with the system based on AC-PC line. From the most internal and lateral point of the anterior and posterior of the PG on the cross section, recording the coordinates of the point(X,Y), Z values can be get through product of multiplition of the thickness and numble of the layers. All point samples of t the most internal and lateral point of the anterior and posterior of the Pre CG in the three-dimensional coordinates can be get. finally. Get the fitting curvilinear equation of the Pre CG projection on the coronal plane and cross section by SPSS17.0.3. One normal adult head coronal-sectional MRI is imported into 3D-Doctor workstation on a microcomputer, segmented Pre CG,postcentral gyrus, lateral ventricle, the telencephalon with different color, reconstructing the cerebral Pre CG tri-dimension with method of surface reconstruction.Results: 1.We can classified the procentral knob into 7 type includes inverted omega(Ω) shape, horizontal epsilon(ω) shape, medially asymmetric epsilon, laterally asymmetric epsilon, null, trifolium, waves variant. Constituent ratio of all types between men and women,right and left have not statistically significant. Constituent ratio of women between left and right have not statistically significant. Constituent ratio of men between left and right have statistically significant(P =0.042). The height of the precentral knob between men and women have nothing statistically significant. However in the inverted omega shape, statistically significant sex differences were observed: the width of the precentral knob of the men are larger than women(P =0.021).2. The three-dimensional anatomy data set of the most internal and lateral point of the anterior and posterior of the Pre CG have been constructed in the three-dimensional coordinates; The fitting curvilinear equations of the most internal and lateral point of the anterior and posterior of the Pre CG projection on the coronal plane and cross section.3. We have gotten a visualization reconstruction model of the Pre CG in the whole brain, replaying their shape and location in vivo brain. Furthermore, reconstructed Pre CG could be made serial inclined planes from random orientations or angles, and rotated by random angles.Conclusion: 1.Classified the procentral knob into 7 type. This new morphologic classification should facilitate the identification of the precentral gyrus in subsequent studies and in everyday practice. Horizontal epsilon(ω) shape of the left are more than the right for the men. In the most common shape,Inverted omega shape,the width of the precentral knob shape in the men are larger than women.2. The three-dimensional anatomy data set of the most internal and lateral point of the anterior and posterior of the Pre CG will provide radiologic anatomy foundation for stereotactic surgery on the development of surgical approach and interventional radiology in the area of the Pre CG; the fitting curvilinear equation of the most internal and lateral point of the anterior and posterior of the Pre CG projection on the coronal plane and cross section will contribute to research on the anthropology and body metrology, and will also help reveal secret of human brain.3. 3D visualization of the Pre CG in vivo brain can display three-dimensional struction of the Pre CG, the relationship with their neighbor structures and have great clinical value in sterotactic surgery, the development of surgical approach and interventional radiology. This model can be also applied in the radiologic anatomy teaching.