KR20100042084A - Filming method of sagittal oblique images of the optic nerve system using mri - Google Patents

Abstract

PURPOSE: A filming method of sagittal oblique images of an optic nerve system using a MRI is provided to prevent the loss of information due to a cross section interval on a transverse section by implementing three dimensional nerve system information on a same plane, two-dimensionally. CONSTITUTION: A reference section is parallel to a line interlinking a front and a back of the corpus callosum of the head. The reference section is perpendicularly formed in the transverse section where a right and a left visual nerve are symmetrical. The reference section is a sagittal section passing through an optic chiasma point. The reference section revolves at 35-45 degrees to the counter clock-wise. The reference section which is revolved at 35-45 degrees is located in the center of the transverse section. A right side visual nerve system is recorded with the state that 25-35 degrees is rotated to the clockwise when the subject is faced with right.

Description

Imaging method of sagittal oblique images of the optic nerve system using MRI}

The present invention relates to a photographing method of the left and right optic nervous system using a magnetic resonance tomography apparatus.

As with the variety of medical imaging devices, various imaging methods have been developed. The purpose of medical imaging tests for accurate diagnosis is to, in principle, obtain as much as possible without distorting the morphological internal information of the patient in the current state of examination. However, in clinical imaging, it is not easy because the human anatomy is curved or superimposed in a three-dimensional structure. In some cases, various methods have been studied for rendering these three-dimensional parts as if they were spread out on a plane to make it easier to observe the structure. Representative examples include panoramic graphy, S-colonography, and stereoscopic imaging.

In the past, the typical use of X-ray general imaging for the observation of the optic nerve system was a Rhese method for viewing the optic foramen. In addition, imaging of the optic nervous system in computed tomography (CT) is simply a cross-sectional examination due to the limitation of the scan angle due to the configuration of the device, or an artificial shade in the image of the region of interest due to the difference in absorption between the bone and the surrounding tissue. You can leave In addition, the three-dimensional imaging by the mathematical algorithm is extremely limited, and has the disadvantage of low soft tissue resolution.

However, magnetic resonance tomography (MRI) devices have higher resolution for soft tissues than CT, the use of various pulse sequences, and three-way deviation (tilt) magnetic field coils (Gx, Gy, Gz). There is an advantage that can freely select the image cross-section using.

The imaging method of the optic nerve system by MRI has not yet been organized, but sagittal image oblique imaging is generally simply oblique scan of the sagittal-coronal cross section with a single angulation. In this method, as shown in FIGS. 1 and 2, the optic nerve located in front of the optic nerve system having a different anatomical position but functionally connected based on the optic chiasma may be well represented. However, in this method of imaging, since the optic nerve crossing, optic track, and optical radiation, which are located rearward, are anatomically and functionally related to each other, their positions in front, rear, left and right coordinates are different. Stereoscopic spatial information could not be represented in a two-dimensional image section.

The optic nerve, visual path, and the like appear sequentially on the cross-section as shown in Figs. 2 and 12 due to the difference in the vertical position due to the anatomical structure, and information loss due to the image cross-sectional thickness and slice gap occurs.

Therefore, the technical problem to be achieved by the present invention is to provide a method of photographing the optic nervous system by reducing the loss of information in the process of displaying this three-dimensional anatomical structure of the optic nervous system as a two-dimensional plane image.

The optic nervous system is roughly the optic nerve (optical nerve), optic nerve crossing (optical chiasma), optic tract, dorsal knee body (lateral lateral geniculate body) and the visual field (optical chattar, optic) It consists of a structure connected by nerve fibers of radiation. Their positional relationship, starting from the rear of the eye to the line of sight, can be easily understood in MRI cross-sectional images of adult heads 6 mm thick and 0.6 mm apart (see FIG. 12). In the image shown from the upper (A) to the lower (D) direction, the whole optic nervous system is a curved shape crossing the left and right of the human body in a diagonal direction, and when viewed in three dimensions from the side, the shape is generally gentle V-shape. It shows the shape, and the rear view line is formed in a scattered structure. In addition, when looking at the positional relationship between the upper and lower position, when the optic nerve crossing point is the bottom (0 point), the front optic nerve and the rear optic eye start at the rear of the eye and are 6-6 mm higher than this, and these nerve fibers are The joint line, which is formed by the knee, extends from about 18 mm higher up to 6 mm rearward. Looking at the anatomical positional relationship in more detail in the cross section, the optic nerve in the posterior eye region is located 28 to 29 mm from the medial sagittal plane to the left and right, respectively, maintaining a distance of about 5.7 cm between the left and right optic nerves. In the direction of winding the upper part of the midbrain, divided diagonally to the left and right, it is located about 2 cm to the left and right at approximately posterior 18-20 mm along the midline, and is located on the cerebral peduncle of the cerebral peduncle. The nerve fibers in the outward circumference connect to the knee joint and then form a line around the lateral ventricle and extend back to the visual area of the cerebral cortex, which is the left and right view on the MRI cross-sectional image. It can be seen that the distance is maintained about 4 cm.

In the present invention, the three-dimensional geometrical neural system has to selectively photograph the left or right side to view the sagittal cross-section image, and the same cross-sectional slope used in the existing imaging method is used to show this on one image plane. It is based on the surprising discovery that a new method of forming a cross section to be photographed with a magnetic field at multiple angles allows accurate and holistic imaging without omission or distortion of the optic nervous system.

That is, the present invention is parallel to the line connecting the front and rear of the head (corpus callosum) to achieve the above technical problem, perpendicular to the cross section of the state in which the left and right optic nerves are symmetric, the central axis (Z axis) is a cross section A reference cross section, which is a sagittal image passing through an optic chiasm point located in the center of the head, (i) in a clockwise direction when the observer looks down from the top of the central axis (Z axis). Rotate 35-43 degrees, and (ii) the axis (Y-axis) in which the reference section rotated 35-43 degrees is located at the center of the cross section and faces in the direction of the eye of the subject to be measured as in (i) rotation. Magnetic resonance tomography (MRI) of the optic nervous system, characterized in that the image of the right optic nerve is taken with the rotated axis rotated 25-33 degrees clockwise when facing each other face to face. Way Provided (see Fig. 11).

The present invention is also parallel to the line connecting the front and back of the corpus callosum and perpendicular to the cross section of the left and right optic nerves symmetrical, the central axis (Z axis) is located in the center of the head in the cross section (i) Rotate 35-43 degrees counterclockwise when the observer looks down from the top of the reference axis, which is the sagittal image passing through the optic chiasm point. ii) the reference section rotated from 35 to 43 degrees, and the axis (Y axis) located at the center of the cross section and facing in the direction of the eye of the subject to be measured as the rotation axis (i) as the rotation axis, It provides a magnetic resonance tomography (MRI) imaging method of the optic nervous system, characterized in that the left optic nerve is photographed in a state rotated 25-33 degrees counterclockwise when facing each other face to face (FIG. 11). Reference).

In optic nerve MRI imaging according to the invention, more preferably, the (i) rotation angle is 37-41 degrees, and (ii) the rotation angle is 27-31 degrees.

More specifically, referring to the right optic nerve system diagram of FIG. 11, the Z-axis is rotated around the sagittal section (the cross-section shown in red), which is a reference section of the first drawing, in the right optic nerve system photograph of the upper part of FIG. 11. Rotates clockwise when viewed from the top, and rotates the optic nerve to the cross section to be photographed, and the rotated cross section is viewed from the front of the subject about an axis located between the Y axis and the X 'axis. When the image was rotated clockwise by a certain angle, the right optic nerve could be best represented as a whole.

In the case of the left optic nerve, the sagittal section, which is a reference section, is rotated counterclockwise about a Z-axis by a specific angle and is rotated counterclockwise by a specific angle about an axis located between the Y-axis and the X-axis. In the same way, the left optic nerve could be best represented as a whole.

However, the present invention relates to the three-dimensional three-dimensional position itself of the cross section for photographing the MRI, and the order of rotation, reference section, etc. do not limit the present invention. That is, even if the initial reference cross-section is different or the order of rotation is different, the three-dimensional stereoscopic position of the final MRI imaging cross section may be the same as the present invention. For example, in the imaging of the right optic nerve, the reference cross section is parallel to the line connecting the front and back of the corpus callosum and the cross section of the left and right optic nerves is symmetrical, and the same as the rotation (i) above. After rotating 35-43 degrees, (ii) the axis (Y-axis) which is located at the center of the cross section of the reference section rotated 35-43 degrees and faces in the direction of the eye of the measurement subject is rotated by (i). The axis rotated as described above is rotated to a rotation axis (ie, an axis located between the Y axis and the X ') and rotated 57-65 degrees counterclockwise when the faces of the measurement targets face each other. The same position as the photographing stereoscopic position can be provided.

In the present invention, the 'right optic nervous system' means including the optic nerve, the optic nerve crossing, the visual path and the visual field starting from the right eye (right eye of the subject) of the head cross-sectional view as viewed from the right as shown in FIG. 3. (Connection of the blue arrow, green arrow and yellow arrow in the right figure of FIG. 3), the 'left optic nerve' includes the optic nerve, optic crossing, visual path, and visual line starting from the left eye of the head cross section viewed from the sky. I mean.

However, since the optic nervous system passes through the optic nerve crossing point and changes from side to side, the concept of the right or left side is relative and the term itself of the right side or left side does not limit the present invention.

The present invention provides a method for capturing optic nerve sagittal cross-sectional images which minimizes information loss of the optic nerve by introducing a geometric approach using multi-direction (sagittal-coronal-cross section) inclination in capturing the sagittal cross section of the optic nerve by MRI. Moozzo method) is provided. According to the imaging method of the present invention, it is possible to photograph an optical nerve, an optic nerve intersection, a visual path, and a part of the visual line of the human cranial brain distributed in three dimensions without disconnection in a two-dimensional image section. Therefore, the method of the present invention can obtain more image information than the conventional photographing method.

As a sagittal cross-section inspection method for viewing the optic nerve by MRI, the method according to the present invention can provide more image information than the conventional imaging method by a simple angle. The imaging method according to the present invention displays information of the three-dimensional optic nervous system in spatial coordinates as a two-dimensional image on one plane, thereby preventing information loss due to the cross-sectional spacing on a cross section, and is a useful imaging technique for MRI optic nerve examination. To provide.

Hereinafter, examples and the like will be described in detail to help understand the present invention. However, embodiments according to the present invention can be modified in many different forms, the scope of the invention should not be construed as limited to the following examples. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art.

The apparatus used in the study of the present invention used a 1.5T superconducting magnetic resonance imaging apparatus (Magnetom Symphony Maestro Class, Siemens, Germany) and a CP head array coil. In general, the thickness of the image section to represent the optic nervous system is selected in the range of 3-5 mm. Therefore, in this experiment, the section thickness was 3-4 mm, section interval 0.1 mm, and FOV 180 mm.

In understanding the following embodiments, it should be taken into account that all MRI measurement devices are manufactured to position the right side of the patient to the left side of the two-dimensional image in the final MRI image, whatever the method of measurement to avoid left and right confusion in practical use. . In addition, in the MRI measuring apparatus used in the following embodiments, when the right optic neural imaging is input as "Sag> Cor (39)> Tra (29)", the three-dimensional stereoscopic position as described in the present invention is It is rotated to have the same result as "Sag> Cor (39)> Tra (29)" in the image result, and in case of the left optic nerve imaging, "Sag> Cor (-39)> Tra (-29)" When rotated to have a three-dimensional three-dimensional position as described in accordance with the present invention, the image result is shown as "Sag> Tra (-39)> Cor (-29)". This should be understood as programming for displaying the right side of the patient on the left side of the image plane, regardless of the imaging position, which does not limit the present invention.

The average of the measured values for head injuries of Korean adult men is as follows.

In the results of the measurement of the skull's appearance in more than 200 Korean males, the average anterior and posterior direction was about 20 ± 1 cm and the average in the left and right directions was about 12 ± 1 cm. In general, Asian heads have shorter front and back appearances than wider ones and wider faces from side to side, so scanning angles for photographing sagittal sections may be slightly different, but clinical trials set angles based on Koreans among Asians. Photographed.

Cross-sectional imaging for planning and establishing an accurate sagittal image was performed in parallel with a line connecting the front and back of the corpus callosum as shown in FIG.

<Estimating angle of shooting plan and focusing point>

Two-dimensional planar image design of three-dimensional multi-section and angle of method were obtained. In the development of the azo method, which is the method of the present invention, the photographing angle for viewing the optic nerve system oblique image of the sagittal section can be estimated geometrically from an image obtained by photographing the head cross section of the subject at a cross section thickness / spacing of 4 mm / 0.1 mm. Could. Based on the optic chiasma, the difference between the optic nerve, the optic tract, and the optic radiation is about 1.8-2 cm in the axial direction of the human body. It could be observed. In addition, the anatomical structure such as the optic nerve maintains a constant width from side to side in the cross-sectional image, thereby enabling multi-angle predictive imaging. In the past, the angle was simply set in one direction for oblique scan of bilateral or unilateral for viewing optic nerve images.

However, MRI uses the magnetic field deviations (Gx, Gy, Gz) to see the sagittal oblique image of the three-dimensional optic nervous system anatomy. It was possible to set the multi-angle to form a three-dimensional plane.

In the present invention, by using a newly developed image inspection technique as shown in the left figure of Figure 5 when applying a deviation magnetic field to the inclined plane of the square with respect to the anatomy of the optic nervous system of the anatomical structure corresponding to the dotted line of the right figure of Figure 5 I could get the video.

The method of the present invention was named as a Moozzo method and photographed as shown in Table 1 below to obtain an appropriate scan angle.

FIG. 5 shows the multiple angles and the emergence image range of the forward direction (direction angle where the optic nerve image of the side to be seen is expected) to see the right optic nerve well. If the direction of the photographing angle is set incorrectly, it may not be able to represent the optic nerve side to be seen. On the other hand, Figure 6 shows the multi-angle and emergent image range in the case of setting the reverse direction (direction angle where the optic nerve image of the side to be viewed is distorted and difficult to see) to see the same right optic nerve system. In this case, the diagonal direction of the anatomical structure of the optic nervous system does not appear, but it can be expected that only one side of the human head appears as a distorted image from the medial sagittal section.

<Appropriate Angle of Optic Nerve Slope Imaging Using Multiple Angles>

As shown in Table 1, an experiment was performed to measure the proper angle of the azo method for viewing the optic nerve sagittal cross-sectional oblique image of the human body using MRI. The thickness was 3 mm for all measurements.

number Scan side Scan sectio angle Drawing Plan / Actual Shooting Video Scan direction One Rt  Sag> Cor (22.9)> Tra (15.0) 7a / 8a Forward, Multi angle 2  Sag> Tra (26.3)> Cor (20.0) 7b / 8b 3  Sag> Tra (31.3)> Cor (20.0) 7c / 8c 4  Sag> Tra (36.7)> Cor (21.6) 7d / 8d 5  Sag> Tra (41.7)> Cor (21.6) 7e / 8e 6  Sag> Tra (39.7)> Cor (21.6) 7f / 8f 7  Sag> Tra (37.4)> Cor (24.0) 7g / 8g 8  Sag> Tra (46)> Cor (20) 7h / 8h 9  Sag> Tra (50)> Cor (20) 7i / 8i 10  Sag> Cor (43.4)> Tra (23.7) 7j / 8j 11  Sag> Cor (33.1)> Tra (-28.0) 7k / 8k Reverse, Multi angle

As shown in FIG. 7A, the medial sagittal cross section image (left), the cross section image (middle), and the coronal cross section image (right) were selected as plan images.

From the axial image, the best view of the optic nerve is selected as the planned image, and the optic nerve and optic chiasm of the subject side is placed in a straight line in the sagittocoronal oblique. The optic nerve was included as much as possible on the straight line of the image section.

In clinical trials, the reference angle of the method of the present invention (absorption method) is a result of reproducibility experiments and the results obtained by varying the angle in the range of 5-1 degrees in the coronal planar plan image of the MR scan. The reference angle is set when the image is close to providing a lot of image information.

In the coronal image, the angle was tilted in the corresponding forward direction so that the visual path of interest could be well represented, so that the center line of the slice passed through the optic nerve. If there is a change in the center slice in the cross-sectional plan image, it is corrected in the (cross-section) image to confirm that the two correspond and check.

In each experiment, the angle measurement of the imaging plan was performed using the program of the MRI device itself, and the angle measurement from the MR imaging plan image was used by Infinitt's star-PACS program for confirmation. The plan of each experiment was plotted, the photographing plan images were shown in the diagram, and each image information was presented as a result. Each captured image is shown in FIGS. 8A to 8K, respectively.

As can be seen from the image results of FIGS. 8H and 8I, it can be seen that the photographing angles of Nos. 8 and 9 of Table 1 are excessive.

8J is a photographing result image of photographing procedure 10 of Table 1 of FIG. 1. The optic nerve system oblique imaging image of the forward angle made at an appropriate angle using the azo method according to the present invention shows both the left and right sagittal cross sections of the human body and the optic nervous system distributed before and after the optic nerve crossing depending on the selection of the photographing direction.

8K is taken according to the photographing procedure No. 11 of Table 1, and it shows that only a part of the optic nervous system is distorted in this image due to the selection of the reverse angle.

<Comparison of Conventional Simple Angle Shooting Methods to Amethyst Methods>

Table 2 below is to compare the comparison and reproducibility of the image of the optic nerve oblique direction by the conventional method and the image by the aberration method by MRI. MRI scan of the sagittal section simple oblique direction by the conventional method was taken as in the photographing sequence 12 and 14 of Table 2, the reproducibility experiment of the azo method according to the present invention was scanned as the imaging sequence 13 and 15 . In the MRI imaging of Table 2, the thicknesses were all 4 mm.

Each shot plan image of Nos. 12 to 15 of Table 2 is shown in FIGS. 9A to 9D, and the actual shot images are shown in FIGS. 10A to 10D, respectively.

number Scan side Scan sectio angle Drawing Plan / Actual Shooting Video Scan direction 12 Both Lt: Sag> Cor (-29.0)> Tra (-0.4) Rt: Sag> Cor (35.0)> Tra (-0.9) 9a / 10a Forward Simple Angle (SA) 13 Both Lt: Sag> Tra (-37.5)> Cor (-29.0) Rt: Sag> Cor (40.8)> Tra (28.7) 9b / 10b Forward multi-angle (MA) 14 Rt Rt: Sag> Cor (35.0)> Tra (-0.9) 9c / 10c (left) Forward Simple Angle (SA) 15 Rt Rt: Sag> Cor (40.8)> Tra (28.7) 9d / 10c (right) Forward multi-angle (MA)

10A is an image of a conventional sagittal cross-section simple angle imaging method according to No. 12 of Table 2 in both optic nerve MRI scans. The left side is taken with sagittocoronal oblique (-29 degrees), and the right side is taken with sagittocoronal oblique (35 degrees). Here, Tra (-0.4) and Tra (-0.9) are the basic angles entered in the shooting plan to maintain the accurate cross-sectional symmetric image. This image shows the front of the optic nerve crossing on both the left and right sides, but because the back is composed of a three-dimensional anatomical structure on the spatial coordinates, it does not appear on one cross section and the whole optic nervous system cannot be observed.

FIG. 10B is an image obtained by simultaneously photographing both optic nerves as an attenuation method by multi-angle imaging of Table 2 to obtain an optic nerve sagittal cross-section image. Since the photographs were taken at the same time, an artificial shade of black stripes occurred, but if ignored, this image shows much of the optic nerve image information of a wider area than that shown in FIG. 10A by the conventional simple angle photographing method.

The left image of FIG. 10C is a right optic nerve system taken by the photographing procedure of Table 2, which is a conventional photographing method, and the right image is a right optic nerve system shown by the azo method, according to the photographing procedure of Table 2. It is a side image. In comparing the two images, it can be seen that the conventional simple angle photographing method and the attenuation method using multiple angles have many differences in terms of image information acquisition.

1 is a diagram showing the anatomy and name of the optic nervous system.

Figure 2 is a cross-sectional image (6 mm thick) of the brain optic nerve area of the human head using MRI, arranged in order in the vertical direction.

3 is a diagram showing a schematic anatomy and spatial coordinates of the optic nervous system.

Figure 4 is a photograph showing a plan image and a baseline for viewing the cross-section of the cranial brain.

Figure 5 is a diagram showing the forward multi-angle (left) and emergent image range (right) expected to see the optic nerve well.

6 is a diagram showing multi-angle (left) and emergent image range (right) that are incorrectly set in the reverse direction to view the optic nervous system.

7A to 7K are photographing plan images of photographing procedures 1 to 11 of Table 1, respectively.

8A to 8K are optic nerve system images photographed according to the photographing procedures 1 to 11 of Table 1, respectively.

9A to 9D are photographing plan images of photographing procedures 12 to 15 of Table 2, respectively.

10A to 10C are images of the optic nervous system photographed according to the photographing procedures 12 to 15 of Table 2, respectively.

Figure 11 is a schematic diagram showing the three-dimensional position of the optic nerve imaging section according to the present invention and two rotations to achieve such a position.

12 are MRI images (transverse cross-sections) of adult heads of a human body taken at a thickness of 6 mm and an interval of 0.6 mm, showing the direction from the upper portion (A) to the lower portion (D).

Claims (4)

Optic chiasm point parallel to the line connecting the front and back of the corpus callosum and perpendicular to the cross section with the left and right optic nerves symmetrical, with the central axis (Z axis) at the center of the head in the cross section. The reference section, which is the sagittal image (i) Rotate 35-43 degrees clockwise when the observer looks down from the top of the central axis (Z axis), (ii) Measuring the reference section rotated from 35 to 43 degrees, and the axis (Y axis) located at the center of the cross section and facing in the direction of the eye of the subject to be measured as the rotation axis, is measured as the rotation axis. In the state of rotating the face 25-33 degrees clockwise when facing each other face to face Magnetic resonance tomography (MRI) imaging method, characterized in that the imaging of the right optic nerve system. The magnetic resonance tomography (MRI) imaging method according to claim 1, wherein (i) the rotation angle is 37-41 degrees, and (ii) the rotation angle is 27-31 degrees. Optic chiasm parallel to the line connecting the front and back of the corpus callosum and perpendicular to the cross section with the left and right optic nerves symmetrical, with its central axis (Z axis) at the center of the head in the cross section. The reference section, the sagittal image passing through the point. (i) Rotate 35-43 degrees counterclockwise when the observer looks down from the top of the central axis (Z axis), (ii) Measuring the reference section rotated from 35 to 43 degrees, and the axis (Y axis) located at the center of the cross section and facing in the direction of the eye of the subject to be measured as the rotation axis, is measured as the rotation axis. In the state rotated 25-33 degrees counterclockwise when facing each other face to face Magnetic resonance tomography (MRI) imaging method, characterized in that the imaging of the left optic nerve system. 4. The magnetic resonance tomography (MRI) imaging method according to claim 3, wherein (i) the rotation angle is 37-41 degrees and (ii) the rotation angle is 27-31 degrees.

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