Technology: The naughty kid ruined my college entrance examination, but I turned over to nuclear fus

Doctor Jiang's eyes had become extremely deep at this moment, and his expression looked very focused, as if he was completely immersed in the process of thinking.

Interrupted by his student Dr. Lin, he suddenly reacted.

"My opinion is the same as yours, if only from a theoretical point of view, there is no problem with these views of his."

"But some are too general."

Old Doctor Jiang took a deep breath and continued:

"This is more like a program than a specific approach, and for our current domestic MRI equipment, what is needed is more than just a program. But.... Being able to say this is also proof that he has some level.

His expression became a little complicated.

At the beginning, when Lu Yu proposed that he had a way to improve China's domestic NMR device technology, Dr. Jiang was actually very disdainful, or did not believe that this kind of thing could really happen.

The reason why he sat here patiently and listened to Lu Yu say a lot.

At first, I just wanted to end this topic as soon as possible, and then let Lu Yu do a deeper physical examination.

However, along with professional knowledge, stubble after stubble came out of Lu Yu's mouth.

Old Doctor Jiang's thoughts have quietly changed, if he just wanted to veto Lu Yu's proposal as soon as possible, and then step into the topic of studying Lu Yu's body, then now for him, compared to checking out Lu Yu's physical examination report, why is it so strange...

Find out if the idea of improving the quality of Longguo's domestic NMR equipment by optimizing scanning parameters will work.

It has become a topic of more concern to him.

Or to put it more appropriately, before you know it, both Dr. Jiang and Dr. Lin have begun to seriously think about whether this guy in front of them is an unlearned liar or a person who can really bring about change!

"Do you have any more detailed ideas?"

After a brief hesitation, Old Doctor Jiang once again looked at Lu Yu and couldn't help but ask with curiosity in his heart.

"Do you think the plan I just proposed is a bit too general?"

Lu Yu also guessed his specific thoughts based on Doctor Jiang's expression.

In this regard, he did not have the slightest strangeness.

After all, if you want to make the two medical bigwigs in front of you believe that their technology is real, it is not enough to come up with some programmatic things, you still have to come up with some practical technologies that can be used quickly, so that it is possible to win the trust of others faster!

Moreover, so much has been done in front of them, and it is time to come up with some real technology to make them feel a little shock.

So, after briefly sorting out the technical ideas about system rewards in my mind.

Lu Yu spoke again:

"If you want to improve the scanning parameters, you must first understand what the principle of MRI is."

"Of course... You two are both experts, so I won't tell you both directly about too much nonsense. Let me explain it in simpler terms. "

In a constant external magnetic field, the nuclei inside the object are distributed according to different energy levels, forming a thermal equilibrium state."

"Then, apply an alternating magnetic field perpendicular to the external magnetic field to the object, and the frequency of this alternating magnetic field should be equal to the resonant frequency of the nucleus, so that part of the nucleus can jump from a low energy level to a high energy level, breaking the thermal equilibrium state."

"Next, the alternating magnetic field is turned off, allowing the nucleus to spontaneously return from the high energy level to the low energy level, while releasing electromagnetic wave signals. Finally, by detecting these electromagnetic wave signals and passing through signal processing and image reconstruction, the image information inside the object can be obtained.

"This is the most basic principle of imaging, and to improve the scanning parameters of an MRI device, you must start with the fundamental nature of its principle."

"That is, from the fundamental problem of imaging, to find a solution to it!"

"A very simple way to do this is parallel imaging."

"Parallel imaging is a technology that uses multiple receiving coils to acquire signals simultaneously and restore the complete image through reconstruction algorithms. It reduces the number of phase encoding steps, resulting in shorter acquisition times and faster scanning. There are many ways to implement parallel imaging technology..." Lu

Yu's description made the researchers next to him scratch their heads.

After all, he is a researcher specializing in aerospace and aviation, and this thing is fundamentally two systems, and it is unrealistic to want to understand what is going on in a short period of time.

However, Dr. Lin and Old Doctor Jiang next to them listened more seriously than the other!

"Another technology that can be used as an aid is compressed sensing technology."

"Compressed sensing technology is more inclined to use the sparsity of the signal to reconstruct high-quality images by nonlinear optimization algorithms when the sampling rate is lower than the requirements of the Nyquist sampling theorem."

"Its main purpose is to drastically reduce the amount of data collected, and from this point to improve the scanning speed."

Listening to Lu Yu's introduction, Dr. Lin subconsciously raised his own question: "Then wait a minute... What you said, I didn't understand a little? "

You just mentioned auxiliary?"

"What does that mean? Aren't these two techniques the best solution for MRI as you envision?

Unconsciously, in his heart, he had completely abandoned his prejudice against Lu Yu, and instead began to seriously think about whether Lu Yu's plan was feasible, and even began to study every sentence of Lu Yu word by word!

"Yes."

"Just like Dr. Lin, you just guessed, what I mainly want to use is not the two techniques I just mentioned."

"These two technologies, although there is no big problem, but as the main solution to improve the scanning parameters... They are not qualified.

Lu Yu smiled mysteriously, and after briefly selling a pass, continued: "

The technology I want to use is the fast pulse sequence technology!"

"Fast pulse train technology?"

The two of them were stunned, and an inexplicable look flashed in the eyes of Old Doctor Jiang, and an idea suddenly popped up in his mind.

But this time.

He didn't interrupt Lu Yu directly, but wanted to hear him continue.

"Yes, you should all know this technology."

"Fast pulse train technology is a technique that improves the efficiency of MRI."

"It can acquire large amounts of data in a very short time and reduce effects such as motion artifacts and distortion."

"There are two main types of fast pulse train technology: single-excitation fast pulse train technology and multi-excitation fast pulse train technology."

"The single-excitation fast pulse train technique refers to exciting nuclei of all sliced regions inside an object with only one alternating magnetic field and collecting data for all sliced regions in one echo period."

Lu gestured in front of the MRI machine and continued:

"This technique can greatly reduce the scanning time, but it also sacrifices some signal-to-noise ratio and contrast. The most common example of a single excitation fast pulse sequence technique is EPI (Echo Planar Imaging).

"In simple terms, EPI is a technique that uses echo signals for spatial encoding and image reconstruction, which can complete the acquisition of an image in tens to hundreds of milliseconds." EPI is mainly used in areas where rapid dynamic observation is required, such as diffusion-weighted imaging (DWI) and functional magnetic resonance imaging (fMRI).

"The technique of multiple excitation fast pulse sequences is a little more complicated."

"It refers to the technical method of excitting nuclei in different sliced regions inside an object with multiple alternating magnetic fields, and then collecting one or more sliced regions in each echo period."

"In a sense, this technology can maintain a certain signal-to-noise ratio and contrast, at the cost of increasing scanning time."

Lu Yu smiled helplessly and continued to analyze:

"The most common example of multiple excitation fast pulse train techniques is fast spin echoes."

"Fast spin echo is a technique that uses multiple echo signals for spatial encoding and image reconstruction, which can complete the acquisition of an image in a few seconds to tens of seconds."

"And it is mainly used in structural MRI, magnetic resonance angiography and other fields that require high resolution and high contrast..."Listening to it

, Dr. Lin couldn't help but feel a little anxious:

"So do you plan to use the single-excitation fast pulse sequence technique, or switch to the multi-stimulus fast pulse sequence technique?"

He is not usually an anxious person.

Merely.... Listening to Lu Yu's narration, he subconsciously became more curious about the technical content behind.

Intuitively, he had a hunch... What amazing technical solutions may appear in this small physical examination center today!

"These two techniques, I plan..."

Lu Yu really wanted to answer, but at this moment, a questioning voice sounded next to him.

"Wait first!"

The person who opened his mouth to interrupt Lu Yu's words was Doctor Jiang.

"Elder Jiang, what's wrong?"

Lu Yu also stopped his mouth and cast his doubtful gaze on the old doctor Jiang on the side.

"I want to know, what do you think about image quality?"

"I have listened to all the ideas you just gave in detail, and I have to say that they are indeed very creative."

"First of all, I want you to apologize first."

Old Doctor Jiang suddenly stood up, and then solemnly said to Lu Yu:

"Although I don't know what kind of profession you are engaged in, I despised you at first, thinking that your lack of understanding of technology came from my pride and prejudice, and you just proved to me that my pride and prejudice are false."

"So I should apologize to you."

"Don't don't, Doctor Jiang, your apology, I can't accept it."

Lu Yu hurriedly said: "You are a doctor, I am a patient. Where is the problem where you apologize to me, let's not say that there was some medical malpractice, right?

"And you were prejudiced against me at the beginning, and I can fully understand your opinion, after all, if any patient says that he can improve the NMR device technology in Longguo, then everyone will think that he is a crazy person!"

"If you didn't send this patient directly to a psychiatric hospital and locked him up, that's all softening, isn't it?"

"How many people can believe him?"

"I'm already very happy if you are willing to sit here and listen to me say this today, and you don't need to apologize to me."

Lu Yu can also understand the feelings of Dr. Jiang and Dr. Lin at the beginning, so he didn't think he was offended or anything, not to mention that it was faster for him, and it was more important to share this technology, and other things could be temporarily sidelined.

"Okay, let's not talk about apologies."

Old Doctor Jiang bowed his head slightly and continued:

"You should have heard my question just now, what do you think about the problem of image quality?"

"Image quality?" Lu Yu was slightly stunned: "What aspect of image quality are you talking about?"

"Frankly, your current thinking completely coincides with my thinking a few years ago. I also thought about using fast pulse train technology to optimize sweep parameters.

"But this idea has an obvious flaw!"

With burning eyes, he continued:

"That is, fast pulse train technology is affected by magnetic field inhomogeneity and magnetic sensitivity, because they cause changes in T2* and phase mismatches, which affect the refocusing and image quality of the echo signal!"

"For NMR technology."

"The quality of the image is definitely one of the first considerations, and I think everyone understands that!"

Dr. Lin next to him subconsciously nodded his head, and his eyes showed a look of approval.

Truly... For MRI technology, image quality is indeed a top priority, only if the image obtained is clear enough...

If there is any large blur on the image, it is likely to affect the judgment of the medical staff, resulting in some unpredictable medical accidents!

Improve sweep parameters with fast pulse train technology.

It would be best if the scanning parameters could be raised to a better point.

But if the cost is to affect the image quality, then it is not clear whether the advantages outweigh the disadvantages or slightly more worries....

This is also why Dr. Jiang has long come up with a similar plan, but he has not really done it.

Because the problem of affecting image quality is too fatal for nuclear magnetic resonance technology, especially in domestic nuclear magnetic resonance devices that are not excellent in their own technology.

Now that Lu Yu has proposed a similar scheme to what he thought of before

, then Dr. Jiang is naturally very curious, has Lu Yu figured out that nature will cause image quality problems?

Feeling the fiery gaze of Dr. Jiang.

Lu Yu pondered for a second, and said slowly:

"This plan you proposed, I may need to think about it before I can answer you."

"Do you still need to think about it?"