Phantom for nuclear magnetic resonance T1 rho sequence and T2 mapping sequence and manufacturing method thereof

Abstract

The invention relates to the field of nuclear magnetic resonance imaging, and particularly discloses a phantom for nuclear magnetic resonance T1 rho sequence and T2 mapping sequence and a manufacturing method thereof, the phantom is a set of phantom composed of nine sub-phantoms, and each sub-phantom comprises the following raw materials: 0-0.4 g of proteoglycan powder, 0.1-0.7 g of agarose powder, 0-0.01 g of a preservative and 20 ml of double distilled water. The invention provides a phantom for a nuclear magnetic resonance T1 rho sequence and a nuclear magnetic resonance T2 mapping sequence and a manufacturing method of the phantom, a series of phantom with different proteoglycan and agarose concentrations are constructed, and a tool is provided for calibration of a T1 rho value and a T2 value between different magnetic resonance scanning devices.

Description

Technical Field

[0001] The present invention relates to the field of nuclear magnetic resonance imaging, and particularly to a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence and a manufacturing method thereof. Background Art

[0002] With the development of nuclear magnetic resonance technology, more and more studies have shown that quantitative magnetic resonance technology can sensitively and non-invasively capture the changes in the internal tissue components at the early stage of intervertebral disc degeneration, providing new possibilities for the early diagnosis of intervertebral disc degeneration. Among them, T1ρ-MR has attracted much attention due to its good performance. T1ρ-MR can reflect the interaction between macromolecules and water in tissues, and can sensitively detect the content of macromolecules such as proteoglycans, so it can be used to explore the biochemical changes of macromolecules in tissues. There are research reports that T1ρ-MR can effectively detect the loss of proteoglycan content in degenerative articular cartilage lesions. In addition, Johannessen et al. found in the intervertebral disc that the T1ρ value (T1ρ-MR relaxation time) is directly related to the proteoglycan content in the nucleus pulposus, and as the degree of intervertebral disc degeneration deepens, the T1ρ value gradually decreases. During the process of intervertebral disc degeneration, the earliest biochemical changes include the loss of the content of water and macromolecules such as proteoglycans in the nucleus pulposus. Therefore, T1ρ-MR is considered an effective method for the early diagnosis of intervertebral disc degeneration due to its sensitive non-invasive quantification ability of proteoglycans. In addition, T2 mapping is also an effective quantitative magnetic resonance technology for evaluating intervertebral disc degeneration.

[0003] Although many studies have used T1ρ-MR and T2 mapping to evaluate lumbar intervertebral disc degeneration, for intervertebral discs with the same degeneration grade, there are differences in the T1ρ values and T2 values measured by different researchers. This difference may stem from the complexity of the quantitative nuclear magnetic resonance sequence, resulting in deviations when using T1ρ and T2 mapping techniques to quantitatively measure intervertebral discs on different magnetic resonance devices. Therefore, in order to improve the accuracy and consistency of the quantitative evaluation of intervertebral disc degeneration, a standard mold is urgently needed to correct these deviations. The current technical problem is to construct an in vitro standard model applicable to T1ρ and T2 mapping sequences, and through background data processing, to calibrate the T1ρ values and T2 values obtained by different magnetic resonance scanning devices. Summary of the Invention

[0004] The present invention provides a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence and a manufacturing method thereof, which constructs a series of phantoms with different proteoglycan and agarose concentrations, providing a tool for calibrating the T1ρ values and T2 values between different magnetic resonance scanning devices.

[0005] The present invention adopts the following technical solutions:

[0006] A phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence, said phantom being a set of phantoms composed of nine sub-phantoms, and each sub-phantom respectively comprising the following raw materials:

[0007] 0 - 0.4 g of proteoglycan powder, 0.1 - 0.7 g of agarose powder, 0 - 0.01 g of preservative and 20 ml of double-distilled water.

[0008] Preferably, the preservative includes sorbic acid powder.

[0009] Another object of the present invention is to provide a method for manufacturing a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence, comprising the following steps:

[0010] Accurately weigh various raw material powders in proportion and pour them into a beaker, add double-distilled water, and place the beaker in a microwave oven for heating;

[0011] Quickly take out the beaker from the microwave oven after the powder is completely dissolved, pour it into a 5 ml glass bottle, and place it at room temperature and let it stand for 1 - 2 h to cool to room temperature;

[0012] Place the phantom in a nuclear magnetic resonance machine, perform T1ρ and T2 mapping sequence scans, measure the T1ρ and T2 values, and construct a linear equation, with the equation R 2 > 0.97 and can be stably stored for a long time.

[0013] Preferably, the heating temperature of the beaker in the microwave oven is 95 - 105 °C.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The present invention provides a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence and a manufacturing method thereof, which constructs a series of phantoms with different proteoglycan and agarose concentrations, and provides a tool for calibrating T1ρ values and T2 values between different magnetic resonance scanning devices. Description of the Drawings

[0016] Figure 1 It is the phantom image of the embodiment of the present invention.

[0017] Figure 2 It is the T1ρ mapping image of the phantom of the embodiment of the present invention.

[0018] Figure 3 It is the T1ρ linear curve of the phantom of the embodiment of the present invention and the image of remaining stable over time.

[0019] Figure 4The T2 mapping image of the phantom for the embodiment of the present invention.

[0020] Figure 5 The T2 mapping linear curve of the phantom for the embodiment of the present invention and the image that remains stable over time. Detailed implementation manners

[0021] The following describes the technical solutions in the embodiments of the present invention clearly and completely with reference to specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0022] This embodiment provides a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence. The phantom is a set of phantoms composed of nine sub-phantoms. Each sub-phantom includes the following raw materials:

[0023] 0 - 0.4 g of proteoglycan powder, 0.1 - 0.7 g of agarose powder, 0 - 0.01 g of preservative, and 20 ml of double-distilled water.

[0024] The preservative in this embodiment is sorbic acid powder.

[0025] Another object of the present invention is to provide a method for manufacturing a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence, including the following steps:

[0026] Accurately weigh various raw material powders according to the ratio, pour them into a beaker, add double-distilled water, and place the beaker in a microwave oven for heating;

[0027] Quickly take out the beaker from the microwave oven after the powder is completely dissolved, pour it into a 5 ml glass bottle, and place it at room temperature for 1 - 2 h to cool it to room temperature;

[0028] Place the phantom in a nuclear magnetic resonance machine, perform T1ρ and T2 mapping sequence scans, measure T1ρ and T2 values, and construct a linear equation. The equation R 2 > 0.97 and can be stably stored for a long time.

[0029] The heating temperature of the beaker in this embodiment in the microwave oven is 95 - 105 °C.

[0030] Example 1.

[0031] The embodiment of the present invention provides a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence. The phantom is a set of phantoms composed of nine sub-phantoms. A set of phantoms includes the first to the ninth sub-phantoms;

[0032] The raw material dosage of the first sub-phantom is: 0.4 g of proteoglycan powder, 0.7 g of agarose powder, 0.01 g of preservative, and 20 ml of double-distilled water.

[0033] The raw material dosage of the second sub-phantom is: 0.35 g of proteoglycan powder, 0.7 g of agarose powder, 0.01 g of preservative, and 20 ml of double-distilled water.

[0034] The raw material dosage of the third sub-phantom is: 0.3 g of proteoglycan powder, 0.6 g of agarose powder, 0.01 g of preservative, and 20 ml of double-distilled water.

[0035] The raw material dosage of the fourth sub-phantom is: 0.25 g of proteoglycan powder, 0.5 g of agarose powder, 0.01 g of preservative, and 20 ml of double-distilled water.

[0036] The raw material dosage of the fifth sub-phantom is: 0.2 g of proteoglycan powder, 0.4 g of agarose powder, 0.01 of preservative, and 20 ml of double-distilled water.

[0037] The raw material dosage of the sixth sub-phantom is: 0.15 g of proteoglycan powder, 0.3 g of agarose powder, 0.01 g of preservative, and 20 ml of double-distilled water.

[0038] The raw material dosage of the seventh sub-phantom is: 0.1 g of proteoglycan powder, 0.2 g of agarose powder, 0.01 g of preservative, and 20 ml of double-distilled water.

[0039] The raw material dosage of the eighth sub-phantom is: 0.05 g of proteoglycan powder, 0.1 g of agarose powder, 0.01 g of preservative, and 20 ml of double-distilled water.

[0040] The raw material dosage of the ninth sub-phantom is: 0 g of proteoglycan powder, 0.1 g of agarose powder, 0.01 g of preservative, and 20 ml of double-distilled water.

[0041] The preservative is sorbic acid powder.

[0042] A method for fabricating a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence, comprising the following steps:

[0043] Accurately weigh various raw material powders of each sub-phantom according to the proportion and pour them into the corresponding beakers, add an appropriate amount of double-distilled water, and place the beakers in a microwave oven for heating at 100 °C;

[0044] Quickly take out the beakers from the microwave oven after the powders are completely dissolved, pour them into 5-ml glass bottles, and place them at room temperature for 1 h to cool to room temperature;

[0045] Place the phantom in the nuclear magnetic resonance machine, perform T1ρ and T2 mapping sequence scans, measure the T1ρ and T2 values, and construct a linear equation. The equation R 2 > 0.97 and can be stably stored for a long time. The images of the obtained phantom are as Figures 1 to 5 shown.

[0046] The prepared phantom is as Figure 1 shown, Figure 2 which is the T1ρ mapping image of the phantom. Figure 3 which is the T1ρ linear curve of the phantom and the image that remains stable over time. Figure 4 which is the T2 mapping image of the phantom. Figure 5 which is the T2 mapping linear curve of the phantom and the image that remains stable over time.

[0047] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, in any regard, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes that fall within the meaning and scope of the equivalent elements of the claims within the present invention.

[0048] In addition, it should be understood that although this specification is described in terms of embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence, characterized in that, The phantom is a set of phantoms composed of nine sub-phantoms. Each sub-phantom respectively includes the following raw materials: 0 - 0.4 g of proteoglycan powder, 0.1 - 0.7 g of agarose powder, 0 - 0.01 g of preservative, and 20 ml of double-distilled water.

2. A phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence according to claim 1, characterized in that, The preservative includes sorbic acid powder.

3. A method for manufacturing a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence according to any one of claims 1-2, characterized in that, It includes the following steps: Accurately weigh various raw material powders according to the ratio, pour them into a beaker, add double-distilled water, and place the beaker in a microwave oven for heating; Quickly take out the beaker from the microwave oven after the powder is completely dissolved, pour it into a 5-ml glass bottle, and place it at room temperature and let it stand for 1 - 2 h to cool to room temperature; Place the phantom in the nuclear magnetic resonance machine, perform T1ρ and T2 mapping sequence scans, measure the T1ρ and T2 values, and construct a linear equation. The equation R 2 > 0.97 and can be stably stored for a long time.

4. The manufacturing method of a phantom for nuclear magnetic resonance T1ρ sequence and T2 mapping sequence according to claim 3, characterized in that, The heating temperature of the beaker in the microwave oven is 95 - 105 °C.

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