What kind of computers are there? What is the difference between computed tomography and magnetic resonance imaging? Contraindications for magnetic resonance imaging
![What kind of computers are there? What is the difference between computed tomography and magnetic resonance imaging? Contraindications for magnetic resonance imaging](https://i2.wp.com/syl.ru/misc/i/ai/355168/2111353.jpg)
Each car has various malfunctions that force its rightful owner to instantly head to the service center and pay money to fix everything. However, in order to save money, not all motorists are in a hurry to meet with qualified specialists in order to subsequently use their services. In this regard, in practice it often happens that it is too late to "save" the car, because it is no longer repairable. In order to prevent such cases from happening in your life, we strongly recommend that you contact the service center through this site. auto-diagnostic.ru.
Experienced specialists conduct daily computer diagnostics and offer all car owners to pass it right now. No one knows exactly when the car will experience problems while driving. Now it is important to prevent further difficulties in order not to fork out for a brand new car in the near future. Diagnostics at the highest level is carried out precisely. Therefore, it makes sense to use the services of experienced professionals in order to receive a detailed report tomorrow on whether everything is in order with the vehicle. In order to avoid any unexpected breakdowns on long trips in your life, we advise you to hurry up while this service is offered at a low cost.
According to professionals, computer diagnostics are the most effective, especially in comparison with a conventional examination. This is due to the fact that any vehicle includes a large number of "intelligent" systems. If you make an ordinary visual inspection, you can easily ignore the vast majority of faults that can be hidden from a person. But, these flaws will never go unnoticed during a full-fledged computer diagnostics. Therefore, we advise you not to hesitate for a long time, but right now go to our service center, where specialists will solve such issues in a minimum period of time.
It is worth noting that with the necessary equipment and due experience, a person can independently carry out such diagnostics in order to avoid additional costs for paying for services to third-party specialists. To do this, you have to undergo special training. If you do not want to wait a long time, then it is best to trust real professionals who will not let you down and will do their job to the highest standard.
Doctors are increasingly prescribing computed tomography and magnetic resonance imaging, as these 2 methods allow the most accurate diagnosis and prescribe the correct treatment. Each of these methods has a number of advantages and is prescribed taking into account contraindications and symptoms.
If you have been assigned one of these methods, there are two important aspects to consider when choosing a clinic: equipment and doctors. To get high-quality images, you should pay attention to the apparatus with which the study is carried out. The network of diagnostic clinics in Russia provides an opportunity to make examinations using the latest generation equipment from leading foreign manufacturers.
Doctors should also be high-level specialists, it is generally accepted that even a nurse can sit behind the apparatus, but this is an erroneous opinion. The doctor not only conducts an examination, but also makes a diagnosis. Try to choose a clinic where doctors constantly improve their skills, participate in lectures and seminars.
The principle of operation of CT
Examinations of this type take place using x-rays, but, unlike conventional x-rays, the device takes many pictures that are processed by a computer and thus a 3d model of the organ being examined is created.
The unequivocal advantage of this method is that the doctor can view the “section” of the organ in any projection and thus make an accurate diagnosis.
During the examination with intravenous contrast administration, the doctors of the Tomograd clinic have the opportunity to distinguish benign formations from malignant ones in:
- Spleen
- Kidney
- abdominal cavity
- Bladder
- pancreas, etc.
Indications for CT
Assign computed tomography for diagnosis:
- bone component of diseases of the spine and joints;
- bone lesions of a tumor nature;
- skeletal damage;
- atherosclerotic changes in blood vessels;
- diseases of the kidneys, lungs, organs of the abdominal and chest cavities, etc. (three-phase contrast study);
How MRI works
Magnetic resonance imaging is fundamentally different from x-ray examination methods. For examination, a magnetic field is used, which is considered absolutely harmless to the human body.
Just like with CT, the images obtained during the procedure are processed by a computer and a three-dimensional picture of the organ being examined is obtained.
Indications for MRI
An MRI examination is prescribed for:
- frequent dizziness
- prolonged headaches
- numbness of the face, arms and legs
- pain and swelling of the joints
- for diagnosing a stroke in the first hours
Not every computer can be considered a gaming computer. For gaming, special components are developed and produced that are designed to process data during games. In addition, additional features, ergonomics and cost will also be different. And even at an equal cost, not every computer will be good in loaded games.
gaming platform
The video card and processor determine the performance in games. If a regular computer can be assembled with an integrated graphics card, then this option is definitely not suitable for a gaming PC. In addition, there are recommendations for the selection of these components.
Multithreading affects the speed of computing in games, therefore, the more cores a central processor has, the better. Even at a slightly lower clock speed, an octa-core CPU will be better for gaming than a six-core one with a higher frequency.
The video card takes on the lion's share of tasks when processing graphics. But not all cards are focused on game graphics. Therefore, you need to choose only from iron, which is developed for the needs of gamers. The leaders are cards with GeForce GPUs, which are adapted to modern game engines at the hardware and software levels and have physical modules for some of the processes.
In addition to high computing capabilities, this class of video adapters has an efficient cooling system, provides for the possibility of safe overlocking, the ability to synchronize with the monitor frequency, additional functions for streaming, recording the passage of levels.
RAM
The more RAM, the better for both regular and gaming builds. The differences are that for the second case, bandwidth is very important. Therefore, it is more efficient to use memory in multi-channel mode. This reduces the load on the CPU by 5-10%, allows you to get fps more by 10%. Therefore, instead of one bar of a certain size, for example, 32 GB, it is better to use 2 bars of 16 GB each.
Cooling
Stable operation at maximum loads depends on the cooling system. The usual system is limited to coolers, they are not always enough to quickly remove heat during gaming. A powerful gaming computer can be equipped with a liquid cooling system.
Ergonomics
The player's reaction and fatigue depend on convenience. Therefore, gaming keyboards and mice are different from ordinary ones. Peripherals designed for different types of games, separate gamepads and modular keyboards are being produced. For normal typing, they are not as convenient as office ones.
Monitors
For a gaming monitor, speed and frequency are important. Monitors with the highest performance are available on TN-matrices. They have a BWB response time (from black to white and back) of 1 ms. But this class of displays has viewing angles within 160°, which can be inconvenient for watching movies or other computer work. A compromise option is IPS matrices with maximum visibility, but slower performance.
In addition, when choosing a monitor for games, it is advisable to stop at models with a frequency of 100 Hz and a synchronization function with a video card.
In modern medicine, a wide range of techniques is used to determine pathologies with varying degrees of accuracy. Apart from them, tomographic research methods are distinguished by their versatility of application and the highest diagnostic value. Computed tomography is being prescribed to patients more and more often, so information about how it differs from other hardware types of diagnostics will be useful.
Computed and magnetic resonance imaging: which is more effective?
Many people mistakenly believe that MRI is analogous to CT. This is not entirely true, these methods are not completely interchangeable due to the underlying principle. So, MRI diagnostics is based on the properties of the magnetic field, and CT is based on the high penetrating power of X-rays. The sensitivity of these methods to certain pathologies depends on the density and composition of the structure under study.
Magnetic resonance imaging is more effective in the study of soft tissue and cartilaginous formations, while the possibilities of computer imaging are more extensive in diagnosing pathologies of skeletal bones, hollow and fluid-filled structures (for example, the largest arteries, bladder, intracranial sinuses, lungs).
When it comes to diagnosing diseases of the cervical region, abdominal organs and retroperitoneal space, the information content of CT and MRI is approximately the same. In the absence of contraindications, preference is given to magnetic resonance imaging, as it is safer in terms of radiation exposure to the body. The exception is in emergency cases, when specialists choose CT, since the procedure takes several times less time compared to MRI.
Ultrasound or CT: which is better?
Ultrasound methods are used to study internal organs, superficial vessels and soft tissues. CT or more precisely ultrasound shows the condition of the bones, brain, deep vessels and lymph nodes. Often, tomography acts as a clarifying diagnostic method after obtaining ambiguous ultrasound results. At the same time, ultrasound has absolutely no contraindications, while X-ray diagnostics have enough of them (pregnancy, early childhood). Which procedure to prescribe in this particular case, the attending physician decides.
Difference between x-ray and computed tomography
X-ray and CT are based on X-ray radiation, in this these methods are similar. The difference between them is that radiography creates images in one plane, not allowing you to look inside the area under study and obtain information about the composition of tissues.
The result of tomography is cross-sectional images taken in different planes. Its main advantage over X-rays is that organs do not overlap on images, and it is possible to differentiate structures even if their density differs by tenths of a percent. X-ray does not provide such information, giving only a general picture.
At the same time, radiography is an order of magnitude cheaper and more accessible. For example, fluorography is carried out in any clinic, while only large medical centers have CT scanners. That is why X-rays are used for primary diagnosis, and CT is used to clarify the results of radiography.
MSCT and CT: what is the difference?
Many patients who are scheduled for an examination are interested in what kind of computed tomography is, and which one is better to choose. As for the second point, it makes sense to rely on the opinion of the attending physician. Let's try to answer the first question here.
Depending on the type of equipment, several types of CT are distinguished:
- Linear computed tomography is an outdated method that is practically not used in modern clinics due to the high radiation exposure and long duration of the procedure. Only one slice is taken in one step.
- Spiral and multilayer computed tomography are advanced types of X-ray diagnostics. The main difference between CT and CT is that the emitter moves in a spiral around the area under study, scanning it in different planes. This allows you to significantly reduce the time of the procedure and the amount of radiation exposure. Today, most patients are prescribed MSCT. What is this survey? Multislice tomographs differ from helical tomographs in that they have several rows of detectors, due to which scanning and data collection is carried out continuously. The examination takes a minimum of time, while it is possible to study the smallest structures. MSCT allows you to perform a three-dimensional reconstruction of the area under study and examine the desired area from different angles.
- Computed positron tomography is the most modern diagnostic method based on the use of radioisotopes. Unlike standard CT, PET studies not the physical features of organs and tissues, but the chemical processes occurring in them. This makes it possible to detect oncological diseases even before a tumor forms, while other methods detect the problem already upon the appearance of a neoplasm and reaching a certain size. Examination is also effective in the search for distant metastases.
Benefits of Computed Tomography
Some of the benefits of computed tomography include:
- high definition images, the possibility of three-dimensional visualization;
- minimum scanning step (from 0.1 mm);
- short procedure time;
- lack of superposition of images of organs and systems in the images;
- high contrast, the ability to differentiate tissues with a density difference of 0.1%.
The article was prepared Recording service for MRI and CT.
Registration for diagnostics in more than 50 clinics in all districts of the city.
Services are completely free for patients.
The service operates every day from 8 am to 24 pm.Find out the minimum cost for your study by calling:
Every more or less experienced user knows that there are different types of computers. In particular, they can be divided into stationary computers, nettops, all-in-ones, laptops, netbooks, tablet computers and even PDAs, although these are gradually disappearing from the market and giving way to tablets and smartphones. Let's define what types of computers exist and what are their main differences.
Personal Computer
This is a classic version of a modern PC, which consists of a system unit and a monitor. Mouse, keyboard, speakers are connected to the block itself. Conventionally, such systems are divided into office, home, gaming. Of course, such a division is very inaccurate, so you need to try to understand this in more detail.
office computers
Compile a document, edit a file, keep accounting records - approximately these types of work are performed by a computer in the office, therefore, its components must be appropriate. For offices, the cheapest and weakest systems are selected, which are suitable only for working with office programs. However, if the company is engaged in drawing in programs like Autocad, then more powerful systems can be used in offices.
Homemade
When choosing a PC for the home, users try to choose the most advanced systems and powerful components, good monitors. Most do not want to buy processors with integrated video cards, but prefer discrete cards. A home computer should be able not only to play movies and open documents, but even games. Such a system should also be equipped with a large monitor - spending time at such a computer at home is much more pleasant.
Gaming
These are the most powerful systems with a huge amount of RAM, a very powerful CPU and an expensive graphics card. Such instances may be water-cooled (rather than conventional air-cooled), since the components of such a system quickly heat up to high temperatures.
In some variants, several powerful video cards are used, which, thanks to Crossfire and SLI technologies, work together. Also, in such systems, new types of disks (SSD) are necessarily installed, which provide a higher speed of data access. Moreover, special types of screens are even used for them. Computers for the game are equipped with cool monitors with a wide diagonal and a minimum pixel response time. The most innovative to date is the Samsung CHG90 GLED model with a diagonal of 49 inches and a unique resolution of 3840x1080.
As for the amount of RAM, gaming systems can use 16 or even 32 GB of RAM, but this is not the limit. Also, in a gaming personal computer, the types of memory should be the most modern. Today it is DDR4.
And all this applies only to personal computers. Different types of platforms can be used in this case. They can be based on AMD, Intel, Nvidia, Radeon components, and sometimes they can be combined with each other.
Nettops
This type of computer is distinguished by its compactness. Nettops are designed for work, poorly suited for home use, and completely unsuitable for gaming. In general, the term "Nettop" was introduced by Intel when demonstrating its new Intel Atom processors, which, as the company's representatives believed, should become the basis and basis for creating nettops.
If we give an analogy, then this type of computer is a stationary analogue of a laptop or netbook. These computers have traditional monitors, a mouse and keyboard, but the system unit used is so small that it can be easily attached to the back of the monitor. As a result, there is no huge box, which saves space.
Nettops are very weak computers that are equipped with budget hardware. Due to the low performance of the components, they heat up very little, which makes it possible to place them in a small box without effective cooling. This box is carefully attached to the monitor. Due to the use of weak components, such systems are very cheap, so they are often bought for use in offices. They enable users to work with office programs, browsers, etc. It is definitely not worth expecting high performance from them. Their main task is to ensure the possibility of staff work and at the same time save the company's budget. They are doing great with her.
Good examples of the implementation of these types of computers are the following models: ASUS Eee Box, Acer AspireRevo AR1600. These systems are based on an Intel Atom chip and an Nvidia graphics card.
Note that although nettops are a convenient solution for offices, they practically did not take root. Most often, even in small companies, cheap desktop computers with classic system blocks are purchased for the needs of staff.
Monoblocks
This type of computer is very reminiscent of a nettop, only in this case there is a screen, components, speakers, a webcam, and a microphone in a single case. Such a computer is ergonomic, takes up little space (at least there is no clumsy system unit), and looks aesthetically pleasing. It is also more portable than a conventional desktop PC.
However, there are also disadvantages of such a device. At a minimum, it is more difficult to repair and upgrade. And if something breaks inside, then it will be very difficult to replace and even more so repair the component. If the monoblock is not under warranty, then you will have to pay for the repair service yourself, and it will cost more compared to repairing a classic desktop computer.
Given the fact that such computers are most often bought for the home, they have recently begun to integrate TV tuners that allow you to watch TV. That is, such a device combines a computer and a TV, which is convenient. More advanced computers are equipped with touch screens, which generally eliminates the keyboard and mouse. Well-known candy bars from Apple are popular, however, they are extremely expensive. By the way, the price is the main disadvantage of such systems. At a high cost, they use weak components, which, if they provide high performance, only when performing template tasks. You can't play games on these computers.
tablet computers
Tablets are very popular today and are actively sold in the respective stores. Initially, it was thought that they would be used as a working tool, although in fact, users buy them as multimedia devices. On tablets it is convenient to sit in social networks, the Internet, watch movies, read books. It may seem that a modern tablet is a reduced monoblock, but, in fact, it is not. In a monoblock, it is possible to implement air cooling by installing fans. There is no such possibility in the tablet, therefore, a priori, weak hardware is used here. And although modern mobile processors are powerful, they are still inferior in performance to full-fledged ones.
laptops
Most citizens have these portable personal computers. This is one of the most practical types of PC, which is very popular. There are many models on the market from different manufacturers.
A feature of the laptop is its portable case, which is divided into two parts: in one part there are components (it can be both powerful hardware and budget), in the other - the screen. Moreover, the type of computer screens can be any: with IPS, PVA, TN, MVA matrix, with large or narrow viewing angles, etc.
As for accessories, there is also room for choice. For work or study, you can pick up a weak laptop with budget hardware, and for games, some manufacturers create quite expensive gaming platforms with efficient cooling and powerful components.
The difference between a laptop and a monoblock or nettop is not only its physical design, but also autonomous operation. Thanks to the use of the battery, the laptop can be used on the street, in a cafe, at the institute. True, modern models without recharging are able to work for three to four hours, but this is already quite good. Some standalone laptops at a low brightness setting can last 15 hours.
By the way, laptops in the West (and in our country too) are called laptops (laptop). They have certain advantages over desktop computers in the form of classic systems, monoblocks and even nettops:
- Light weight.
- Compactness and possibility of transformation.
- Autonomy.
At the same time, laptops have the same capabilities as conventional stationary models. They are initially equipped with adapters for receiving a Wi-Fi signal, a webcam, and a keyboard (built into the case). The touchpad serves as a mouse, although a full-fledged mouse can be connected via the USB interface.
At the moment, many manufacturers produce laptops. Samsung, Acer, Asus, Lenovo products are very popular. These companies offer a fairly large selection of laptops in the middle price range. Manufacturers such as MSI are introducing high-end laptops. They specialize in the implementation of gaming platforms with efficient cooling systems and the best hardware. Naturally, a computer with productive components will be able to process any kind of information. And just because it was designed for games doesn't mean it can't work.
Netbooks
Once laptops became very popular, some manufacturers took a bold step towards reducing the already compact devices. As a result, netbooks appeared - smaller analogues of laptops that had 10-inch displays (most often the screen diagonal was just that). It is difficult to say what kinds of work a computer of this type performs. Most likely, they were intended for accessing the Internet, working with office applications, although their hardware was so weak that it was not possible to launch a couple of extra processes. Typically, netbooks used Intel Atom processors, which Intel previously made for nettops, they found their way into netbooks.
And although such models were compact and very light, they very quickly disappeared from the market due to low demand. Today it is difficult to find a netbook in a store, as it is unprofitable to sell them. Everyone prefers to use classic laptops, despite the fact that they are bigger and heavier.
Smartphones or PDAs
Previously, PDAs (personal pocket computers) were in units. However, this gadget did not catch on, as soon after its introduction, ordinary mobile phones were transformed into smartphones. They improved, became affordable, so the need for a PDA has completely disappeared. In terms of their device, smartphones are very close to tablet computers and differ from them only in a smaller screen and the presence of slots for SIM cards, which allows you to make calls.
Finally
The personal computer and its types are constantly changing. It is possible that in the near future there will be some new type of PC that will revolutionize the field of digital technology. Sooner or later, this will definitely happen, because every year the components become more powerful and productive.