Method for acquiring a vascular wall image from magnetic resonance imaging

Abstract

Images where the vascular walls are automatically divided are obtained by obtaining two MRI images that reflect different properties of the blood vessel and obtaining the difference between the two images. This can image both the vascular inner and the outer walls, thereby obtaining the exact size of the blood vessel, and the thickness between the vascular inner and outer walls. Therefore, it is possible to stably perform the operation using a stent with an accurate size during the stent procedure.

Claims

1. A method for acquiring a vascular wall image, which comprises the steps of: obtaining a first magnetic resonance image of a first type, the first magnetic resonance image reflecting a first structural property of a blood vessel; obtaining a second magnetic resonance image of a second type that is different from the first type, the second magnetic resonance image reflecting a second structural property of the blood vessel that is different from the first structural property; determining a difference between the second structural property of the second magnetic resonance image and the first structural property of the first magnetic resonance image; and providing the vascular wall image based at least on the difference between the second structural property of the second magnetic resonance image and the first structural property of the first magnetic resonance image.

2. The method for acquiring MM images according to claim 1, wherein the first and second structural properties include one selected from the group consisting of: a form or thickness of a vascular membrane constituting the blood vessel, a form of the vascular inner wall, a form of the vascular outer wall, and a blood flow.

3. The method for acquiring MM images according to claim 1, wherein the first magnetic resonance image is a CISS (Constructive Interference in Steady State) T2/T1 weighted image.

4. The method for acquiring MM images according to claim 1, wherein the second magnetic resonance image is a T2-weighted image.

5. A method for acquiring a vascular wall image, which comprises the steps of: obtaining a first magnetic resonance image of a first type, the first magnetic resonance image reflecting a first structural property of a blood vessel; obtaining a second magnetic resonance image a second type that is different from the first type, the second magnetic resonance image reflecting a second structural property of the blood vessel that is different from the first structural property; obtaining a third magnetic resonance image of a third type by inverting the first structural property of the first magnetic resonance image; determining a difference between the second structural property of subtracting the second magnetic resonance image and the first structural property of the third magnetic resonance image; and providing the vascular wall image based at least on the difference between the second structural property of the second magnetic resonance image and the first structural property of the third magnetic resonance image.

6. The method for acquiring MM images according to claim 5, wherein the first and second structural properties include one selected from the group consisting of: a form or thickness of a vascular membrane constituting the blood vessel, a form of the vascular inner wall, a form of the vascular outer wall, and a blood flow.

7. The method for acquiring MM images according to claim 5, wherein the first magnetic resonance image is a CISS (Constructive Interference in Steady State) T2/T1 weighted image.

8. The method for acquiring MM images according to claim 5, wherein the second magnetic resonance image is a T2-weighted image.

9. A method for acquiring a vascular wall image, which comprises the steps of: obtaining a first magnetic resonance image of a first type, the first magnetic resonance image reflecting a first structural property of a blood vessel; obtaining a second magnetic resonance image of a second type that is different from the first type, the second magnetic resonance image reflecting a second structural property of the blood vessel that is different from the first structural property; obtaining a third magnetic resonance image of a third type by inverting the first structural property of the first magnetic resonance image; determining a difference between the second structural property of the second magnetic resonance image and the first structural property of the third magnetic resonance image; and providing the vascular wall image based at least on the difference between the second structural property of the second magnetic resonance image and the first structural property of the third magnetic resonance image, wherein the first magnetic resonance image is a CISS (Constructive Interference in Steady State) T2/T1 weighted image, and wherein the second magnetic resonance image is a T2-weighted image.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1(a)-1(c) shows MRI images with different properties, which represent TOF Angiography, T2 weighted, CISS T2/T1 weighted images with respect to the head area.

(2) FIGS. 2(a)-2(c) shows partial enlarged vascular images of the MRI images with different properties of FIGS. 1(a)-1(c).

(3) FIG. 3 is a flow chart representing the method for acquiring vascular wall images according to an embodiment of the present invention.

(4) FIG. 4 shows images treated according to the method for acquiring vascular wall images according to an embodiment of the present invention.

(5) FIGS. 5(a)-5(b) shows enlarged images of the images treated according to the method for acquiring vascular wall images according to an embodiment of the present invention.

DETAILED DESCRIPTION FOR CARRYING OUT THE INVENTION

(6) Hereinafter, preferred embodiments of the method for acquiring vascular wall images through the magnetic resonance imaging system according to the present invention are described in detail with reference to the accompanying drawings. However, description concerning well-known functions and configurations which can make the subject matter of the present invention unnecessarily vague will be omitted.

(7) The configurations of the MRI system as applied to the present invention are widely known in the art and so the description thereof is omitted.

(8) FIGS. 1(a)-(c) shows MRI images with different properties, wherein (a), (b) and (c) respectively represent TOF Angiography, T2 weighted, and CISS T2/T1 weighted images with respect to the head area. FIGS. 2(a)-2(c) shows images which enlarge the vascular parts. Further, the figures attached to the present specification represent the images acquired from the head part of a normal subject using a clinical 3.0 Tesla magnetic resonance imaging device.

(9) TOF Angiography, which measures the blood flow of veins and arteries in the human body using a MRI device and then render them as images, utilizes the blood flow rate, i.e., a property according to TOF (time of flight), using a T1 weighted imaging of the blood flow. TOF Angiography can present in detail a variety of vascular structures of individual patients with excellent image resolution. Accordingly, TOF Angiography is one of the most common vascular imaging techniques that are currently used in the medical field. Furthermore, as related medical techniques continue to develop, complex blood flow phenomena such as turbulence can also be diagnosed. In recent years, microvascular image can be obtained. As such, the speed of development thereof is fast. Accordingly, TOF Angiography is known to be the most suitable method to obtain overall imaging of the blood vessel, but there is a probability that the blood flow rate could be changed by the vascular inner wall structure, and as a result of which, all of the structures of the vascular inner and outer walls could not be entirely identified.

(10) The T2 weighted images represent a transverse attenuation due to T2 relaxation by the impact between the spindles and this can be used to measure the thickness of the tunica adventitia.

(11) CISS (Constructive Interference in Steady State) T2/T1 weighted images can image a tunica media site of the blood vessel and at the same time measure the signal of the blood flow.

(12) FIG. 3 is a flow chart representing the method for acquiring vascular wall images according to an embodiment of the present invention. FIG. 4 shows images treated according to the method for acquiring vascular wall images according to an embodiment of the present invention.

(13) As shown in FIG. 3, CISS T2/T1 weighted imaging (410) is acquired (S310), and this image is allowed to invert, thus obtaining an inverted image (420) (S320).

(14) Next, separately acquired T2 weighted image (430) is subtracted from the inverted CISS T2/T1 weighted image (420), thereby obtaining an image (440) where the vascular walls are automatically divided.

(15) FIGS. 5(a)-5(c) shows enlarged images of the images treated according to the method for acquiring vascular wall images according to an embodiment of the present invention.

(16) FIG. 5(a) represents a tunica adventitia, and FIG. 5(b) represents a tunica media.

(17) As shown in FIGS. 5(a)-5(c), simply subtracting a T2 weighted image from two MRI image, that is, from the inverted CISS T2/T1 weighted image (420), can obtain an accurate structure including the vascular inner and outer walls, and an accurate measurement is possible without any element influencing the vascular structure, for example, the blood flow rate being changed by the vascular inner wall structure or a catheter being inserted into the blood vessel for the administration of a contrast media.

(18) The above-described embodiments illustrate that an image where vascular walls are automatically divided is obtained by inverting the CISS T2/T1 weighted image therefrom and subtracting T2 weighted image from the inverted CISS T2/T1 weighted image, but the two MRI images that reflect different properties of the vascular outer and inner walls are not always limited to the above two. Specifically, if the difference between the image capable of representing a contour of the vascular outer wall and the image capable of representing a contour of the blood flow and the vascular inner wall can be obtained, it is possible to obtain a similar effect. That is, the two images used may be images which include one selected from the group consisting of: the form or thickness of the vascular membranes constituting the blood vessel, the form of the vascular inner wall, the form of the vascular outer wall, and the blood flow. For example, the above advantages can be accomplished even by a combination of T1 image and T2 image, Proton image and T1 image, Proton image and T2 image, T1 image and T2* image, Proton image and T2* image, and the like.

(19) Two MRI image used to obtain the automatically divided vascular wall images can be obtained by any manner or order. However, obtaining the images at a similar time would be advantageous to obtain an accurate result.

(20) Although the forgoing is described with reference to the preferred embodiments of the present invention, it will be appreciated by those of ordinary skill that various changes and modifications can be made to the present invention without departing from the sprit and scope of the invention as set forth in the claims below.