Imagining Measurement Of The Important Cranial Structures Of Chinese Living Body

There are a lot of international work and relative researches which have been done about the measurement and location of cranial stucture at present.But the datas in relative reports,documents and published books were mostly taken by anatomizing the head of the corpse,rarely from the living body.This experiment acquires the datas by measuring the CT and MRI reports in the Imaging Center of Shandong University Qilu hospital,thus it is the measurement of living body.So that we can derive the length and width datas and so on, and three-dimensional location of Chinese skull and some important intracranial sructures..Objective:The main purpose of the experiment of measuring the cranial structures is to take the statistic reseach of the living body,and provide evidence for the relative clinical operation and diagnosis .Now we present the items seperately as following:the measurement of anterio-posterior diameter and left-right diameter of the skull,calculating out the length-width index to get the Chinese skull-shape distribution;Measuring the length of AC-PC line and set up a 3-D coordinate;measuring the length,width and height of hemisphere,in order to compute the volume of Chinese hemisphere and provide evidence for the clinical diagnosis;measuring the relative structures of lateral ventricle and the angle between posterius and midmost sagittal plane to provide reference for the clinical diagnosis of brain atrophy and hydrocephalus and the operation of ventricle puncture;measuring the incline angle of anterior limb and posterior limb of internal capsule comparing with the length-width index of skull,in order to know whether they are relative;measuring the length and width of caudate nucleus head,dorsal thalamus,lentiform nucleus and the solid location of its edging polar,so to provide evidence for the sterio direction;measuring the length,width ang height ofhypophysis to conduct the clinical work;measuring the width of precentral and postcentral gyrus to provide reference for the clinical diagnosis.MethodsrThe normal samples are sifted out from the quantity of CT and MRI examinations using the spiral CT and PHILIPS 1.5T MRI machine that are , produced by American GE Company in the imaging center of our hospitaLFrom these normal head imaging documents of CT and MRI (include different age guoup of male and female),we measure the index and items that are clearly presented with Germany Brain LAB Vector Vision Nerve Guiding System and PatXfer SoftwareSystem seperately.Then we statistic and analyze these datas with SAS.SPSSll.O data statistical software to get the mean and standard difference of all age group and all index According to the inference,we compute the total sample (ie. Chinese total index) in the credible range of 99% or 95% and do relative test of necessary items.We test among the index that can be measured both in CT and MRI to compare whether there is difference between the two imaging method.At last,we compare the result with the datas that get by anatomizing corpse to see whether there is obvious difference.This experiment regards AC-PC line as the line from the midpoint of anterior commissure's posterior edge to the midpoint of posterior commissure's anterior edge,and calls the horizontal plane which passes the AC-PC line basal axial plane, and regards the basal coronal plane as the coronal plane that both pass the midpoint of AC-PC line and vertical to the axial plane, adding up the midmost sagittal plane of the brain as the basal sagittal plane.Thus the three basal planes are set up.The point of intersection of three basal planes ,ie,midpoint of AC-PC line,is charged origin(0).The aixis^e,Y-axis, which passes origin and goes from anterior to posterior is regarded as sagittal axis(in superposition with AC-PC line);The axis which passes origin from up to down and is vertical to Y-axis is regarded Z axis; The coronal axis which passes origin from left to right and is vertical to Z-axis is regarded X-axis. The X,Y,Z-axis so you say is regarded three basal line.Compare to these planes and axises we can measure and describe the size of some cranial structures and their 3-D locations.When making 3-D location,by Cranial Planning System we go on 3-D solid reconstruction to the imaging datas which are acquired from lamina scanning,andthen decide AC-PC line(Y-axis) and its midpoint(O);We can decide the X-axis and Y-axis through setting target and operation routine repeatedly,and then there is the location of solid cooordinates origin in the axial planes.According to the origin in every axial plane we can seperately ensure a base line in coronal and sagittal basal plane which parallel to X-axis and Y-axis,so we can measure the distances from every structure to the 2 baselines,and then the Y location and X location of the structure can be decided.The Z location can be decided alikely.So,the 3-D location of the most external,internal,anterior and posterior point of the measuring structure can be decided,and we can ensure the center location of the stucture combining the highest and lowest point.Results: The measured samples are divided into 4 groups according to their age and sex :<2 years,2-18 years, 18-60 years old and >60 years old.According to the CT and MRI imaging documents we get the results seperately: skull long and width,and long-width index; length,width and height of hemisphere and long-width index;the venticle cerebrum matter ratio of lateral ventricle anterius and posterius,the angle between posterius and the midmost sagittal plane,and the distance from posterius to occipital;internal capsual incline angle and skull long-width index ratio;the long,width and their center-solid-locations of some structures of basal nucleus and dorsal thalamus; the length,width ang height of pituitary;the width of precentral and postcentral gyrus;the long of AC-PC line.The detailed datas are presented in the table of the body.Conclusions:By analyzing the result of this experiment ,we can conclude that :with the growth of the age ,the anterio-posterior diameter and left-right diameter of the skull ,the absolute length and width of hemisphere, its length-width index gradually reduce. It shows that the cranium shape changes from round to long with the growth of the age,and the same is hemisphere. The cranium-shape is different in different age group and it is mainly rectangular-shape in adult There is no obvious different of the skull between the CT and MRI group ,but there are obvious difference of the hemisphere.Maybe this is mainly caused by measuring variance.The length and width of the skull is positive relevant with that of the hemisphere.The ventricle cerebrum matter ratio of comu anterius ventriculi lateralis all above 0.30 both in the 2-18 years group and the adult group (<2y about0.22,0.23);the ratio of the posterius is between 0.45-0.49 let alone the sex and age. The angle between posterius and midmost sagittal plane is in the range of 45-50 degree.no matter the gender or age.The distance to the occipital bone in the 4 age group is 36.66-37.37mm, 45.95-47.71mm,46.26-48.88mm,43.33-47.86mm seperately.There is little variation between tlie CT and MRI report for the female 2-18 years group.male >60 years group. In addition, the angle beween posterius and midmost sagittal plane is relative with tlie length-width index of the skull,while the distance between posterius and occipital bone is relative with the length of the skull.The ratio of the incline angle between anterior and posterior limb of internal capsule to the length-width index of the skull is fairly constant (varies between 0.71-0.74 and 0.97-1.04),so they are relative with each other.The length-width statistic datas of the head of calculate nucleus ,dorsal thalamus,lentiform,and 3-D location of central point that get by the edging polar is approximative with the datas that get by anatomising the corpsal skull. The result of CT group and MRI group is no obvious different .Males pituitary is smaller than the females in all the length ,hight,and width.There is great different between them .There is different between the inactive and active pituitary, and the size of pituitary is affected by age .The variance of precentral and postcentral gyrus is fairly great ,and the result in CT and MRI measurement has great difference.The anterio-posterior commissure diameter increase gradually with the increase of the age .It is 21.27mm in adult -male and 21.17mm in adult female ,which is approximative with the corpse anatomizing.