C-Arm Machine.

 Introduction

A C-arm machine is a medical imaging device that works based on x-ray technology.  The name c arm machine is derived from a C-shaped arm that is used to connect the X-ray source and x-ray detector to one another. The first C-arm machine was introduced in 1955. As medical imaging has an important role in different diagnoses and treatment of patients. It has become important for medical practitioners in order to have a thorough understanding of many different complicated techniques exist. 

Since the introduction of the c arm machine, there are so many technologies are advanced. These machines are highly flexible and which is widely used in different medical practices. For instance, they are widely used during orthopedics, anesthesia, and various complicated surgeries. Nowadays, movable medical imaging systems are an important part of everyday life. 

Different specialists in the fields like surgery, orthopedics, vascular surgery, traumatology, and cardiology use c-arm machine for surgical operation imaging.  The c-arm machines provide high-resolution x-ray images in real-time medical imaging so that it allows the physician to monitor progress happen at any time during the operation and immediately make any corrections that might be necessary. As a result, the treatment will be good and the patient may recover very quickly.

What is a C-arm Machine?

C-arm machines are medical imaging devices which are work based on x-ray technology.  They are highly flexible and used in various OTs in hospitals. The name c- arm is derived from the c-shaped arm present in the device, which is used to connect the x-ray source and detector together. 

COMPONENTS OF C-ARM MACHINE

In general c-arm machine is made up of mainly three parts.

1. X-ray Generator:-

An x-ray generator is the main part of the c-arm machine which produces x-rays whenever an electrical current is applied to it.  Through an x-ray generator, the current is allowed to flow. An x-ray generator is a device that acts as the primary control mechanism for the entire c-arm machine. An x-ray generator is placed inside the frame where the c-arm is mounted and it can be directly controlled by the work station unit so that the operator can the operation of the system. 

2. Imaging system

One of the main parts of the c-arm machine is the imaging system. The imaging system of the c-arm machine has the ability to move in multiple directions in a single procedure. Due to this c-arm machines are highly advantageous during different surgical activities. Such as ortho, urology, and cardiology. The whole system is highly compact and has lightweight so that allows multiple movements in various directions.

3. Work Station

The workstation is the major part of the c-arm machine. The entire activity of the c-arm machine is controlled with the help of work station. So, the workstation is called the brain of c-arm machines.

WORKING PRINCIPLES OF C-ARM MACHINE

The C-arm machine consists of an x-ray generator and an x-ray image intensifier. An x-ray generator emits x-rays that penetrate the patient’s body. Then the image intensifier part changes the x-rays into a visible image which is displayed on the c-arm monitor. 

The c-shaped connecting element of the c-arm machine allows the movement of a machine horizontally, vertically, and around the swivel axes, so that x-ray images of the patient can be taken from any angle.

Applications of c-arm Machine  

• During different surgeries, the real-time image visualization of internal organs like the liver, kidney, bone, and many different anatomical structures can be obtained.

• C-arm systems of the c-arm machines can guide a needle placement procedure usually it is applicable during injecting Anastasia. Because they allow us to identify the exact place where the medication can be inserted.

• C-arm machines are widely used during orthopedic, different complicated surgeries, and indifferent emergency procedures.

Types of c-arm Machine

1. Fixed c-arm/ Cath Lab:-

Fixed c arms also called Cath labs which produce highly detailed imaging with high generator output in KW.

2. Mobile c-arm

Mobile c-arm unit offers highly cost-effective imaging so that we can get enough images for every clinical procedure.

3.  Mini c-arm

They are like conventional c-arm used x-rays to provide images. But c-arm offers a better advantage than conventional c arm machines. It is a surgeon operated and it is not required to have a radiographer.

• We will have better workplace access due to its small size. Because it is so simple to use and compact, it is popular for daily use, particularly for hand, ankle, and foot surgeries.
• Better accuracy and enhanced maneuverability
• Reduced delays and lower cost of surgery

Advantages of c-arm Machine

• The major advantage of c-arm machines is their ability to move in different directions so that we can achieve the optimum angle for high-quality images.
• C arm machines are widely used during complicated surgeries. If there is a need to place during surgery, c-arms are highly advantageous.

Disadvantages

The device can rotate in multi directions which leads it to offer poor image quality. 

When the device is put for a longer operation time it will prone to heating.

If the exposure of the eye to the machine increase it will cause some eye damages.

When we use vertical AP with a tube on top the high exposure will cause head and neck pain.

Trimming down the size of the c-arm machine leads to positioning and angulation limitations in the operating room.

                         

Use of the c-arm machine in orthopedic surgery

They are mainly used in studies that require maximum positional flexibility. This includes: -

• General surgery, orthopedic procedures, and urology procedures
• Vascular and neurology procedures
• Cardiac procedures

Possible troubles arise in C-arm machine

• During calibration, a grainy image will get displayed.
• Image quality is also often affected by dust or lint particles in the Ⅱ or CCD camera. 
• Charger fail error
• X-ray tube may be pitted or the image intensifier might be old
• Low mA error
• Hard drives may fill or need replacing
• Communication error
• foreign objects may obscure the C-arm image.

Troubleshooting of C arm machine

• In case of an unresponsive or faulty error in the image processing of the c arm machine which is a digital artifact, we have to unplug and reinsert the cables and boards.

• For physical artifacts, we have to use a cleaning lens manually with an eyeglass cloth. If the problem persists, there is a good chance the artifact is lodged inside the camera.

• If wiping the lens fails removing the image intensifier grid panel and cleaning behind the grid with an air puffer is enough solution for the artifact issues. If this also not working, we have to replace our machine.

• Grainy or a high contrast image will occur when the c arm is positioned near different tissue densities such as the thoracic spine and lumbar spine which are caused when AEC (automatic exposure controls) tries to adjust to both densities. So, in this case, we have to center the tube to the densest area first and wait for AEC to adjust then move to the body part being imaged.

Article Contributed By:-

1. Tseganesh Shewa  - https://www.linkedin.com/in/tseganesh-shewa-7351a1220

2. Selamawit Getachew - https://www.linkedin.com/in/selamawit-getachew-322618220