Overview of Fluoroscopy Orthopedic Assessment, Protocols, and Interpretation
In 1895, a scientist named Wilhelm Röentgen discovered what we now know as X-rays. He used the letter “X” to describe these previously unknown rays. Just two weeks after making this discovery, Röentgen produced the first X-ray image – a picture of his wife’s hand. The New York Times commented that this innovation could transform modern surgery by helping doctors detect foreign bodies. Since then, X-rays have advanced tremendously. We’ve gone from blurry images of bones to precise 3D imaging.
These days, X-rays are the main tool used in orthopedics, a branch of medicine dealing with the musculoskeletal system. X-ray units that could be moved around were first developed by a scientist named Madam Marie Curie. They were initially used to assist military surgeons in the field.
Radiography, an imaging technique using X-rays, is not just about static images. It can also take real-time images and videos of the innards of a patient. The process is called fluoroscopy. The first version consisted of an X-ray machine and a fluorescent screen. However, they weren’t bright enough. To solve this, image intensifiers with lenses and mirrors for magnification were invented. Eventually, a video camera and monitor were added, making the images easier to view.
A device called the C-arm was also developed. This is an X-ray machine structured like a half-moon. This made it possible for the machine to move in all directions. The C-arm was connected to an image intensifier, a workstation unit, and a monitor to enhance image quality and increase accessibility. The addition of digital imaging technology further improved the image quality and allowed for the digital recording of images.
An orthopedic surgeon often uses a fluoroscopy imaging unit. Despite this, there’s still a lack of knowledge regarding its proper usage and safety. To help young surgeons more effectively and safely use radiation, this article provides basic recommendations about using fluoroscopy.
Why do People Need Fluoroscopy Orthopedic Assessment, Protocols, and Interpretation
Fluoroscopy, a type of imaging technique that uses X-rays, is often used in orthopedics, a branch of medicine that deals with the musculoskeletal system. It helps in diagnosing diseases, aids during minor procedures, assists in pre-surgery planning, and is useful during surgery. Here are some ways doctors use fluoroscopy in everyday orthopedic practice:
Diagnostic Use of Fluoroscopy
Fluoroscopy can be used to check joints for any signs of damage or changes in shape, indicating diseases like arthritis. It can also be used in a procedure called arthrography, where a dye visible on X-rays is injected into a joint to check how well it functions. This is especially useful in inspecting hips in children. Fluoroscopy can also guide doctors during a biopsy, a procedure where a small piece of a diseased bone is removed to examine it for disease.
Using Fluoroscopy in Daycare Procedures
Doctors also use fluoroscopy to guide them during minor procedures. It is used for diagnostic and therapeutic injections into a joint to treat conditions such as adhesive capsulitis (frozen shoulder), synovitis (inflamed joint lining), and osteoarthritis. Fluoroscopy helps ensure that contrasting agents for CT or MRI scans, or medicine for pain relief, are injected accurately into a joint, spinal nerve root or the small branches of the spinal nerves.
Use in Pre-surgery Planning and During Surgery
Fluoroscopy can be used before surgery to assess a deformity when the patient is under anesthesia. It can also be used during surgery to check that a joint or a fractured bone has been aligned properly after a surgical procedure to correct its position.
Fluoroscopy in Trauma Surgery
In trauma surgery, fluoroscopy improves the precision of procedures to repair joint and pelvic fractures. It is effectively used to place screws in the spine during spinal surgery, and in a procedure called percutaneous vertebroplasty, which helps stabilize spinal fractures.
Equipment used for Fluoroscopy Orthopedic Assessment, Protocols, and Interpretation
Understanding the equipment used in a procedure called fluoroscopy is important to safely use X-rays and get clear images for diagnosis or treatment. The basic tools needed to produce X-rays are:
* An X-ray generator and tube: This is where a high-voltage generator and an X-ray tube work together to create X-ray radiation. Electrons are emitted, or let out, from a negatively charged part called a cathode, and they are sped up towards the positively charged tungsten anode. The X-ray photons are then produced when these high-powered electrons slow down in the anode. The radiation output can be set to either pulses or continuous waves.
* Beam filters: Aluminum or copper filters are used to remove the low-energy X-ray photons from the beam. These photons are absorbed shallowly, and do not help in the quality of the image. If not removed, they increase the radiation dosage given to patients. Choosing the right filter is important to balance both the image quality and the radiation absorbed by the patient. When photons pass through filters, they tend to have higher average energies than those that are unfiltered. This makes radiation penetrate easily, reducing the dose needed for a good image.
* Collimator: Since X-rays are sent out in all directions from the tube, collimators are used to limit the X-ray field to a specific area and decrease spillover radiation. Using unnecessarily large X-ray fields can increase the patient’s dose and decrease image quality. Therefore, two sets of adjustable shutters are attached to the X-ray tube to limit the field. A light is used to help with aligning the field on the patient.
* Patient table: This table should be sturdy enough to hold the patient but also should not absorb too much radiation to prevent an excessive exposure while getting a good image.
* Grid plate: Common in fluoroscopy, anti-scatter grids are used in procedures that involve high scatter. They consist of lead strips that absorb radiation, separated by transparent materials like paper. They can be removed based on the procedure’s needs.
* Image intensifier: This important tool converts the energy from the remaining ray beam into an image suitable for video recording or display. It ampilfies the image electronically to get better-quality images with reasonable radiation dosage. Nowadays, image intensifiers with video capture are often replaced by flat-panel receptors which are compact, flexible and do not distort images.
* Television and recording system: High-quality displays are necessary for the staff to see small details and slight contrasts. Usually, flat-panel LCDs with high contrast ratios are used to achieve the widest range of grey levels possible.
Preparing for Fluoroscopy Orthopedic Assessment, Protocols, and Interpretation
Fluoroscopy is a type of medical imaging that exposes the patient and the medical staff to some degree of radiation. Therefore, it’s really important that everyone involved is aware of the possible risks. Also, the doctor performing the procedure should know the basic principles related to radiation to effectively reduce the amount used.
Before the Procedure:
The patient must give their permission (aka, informed consent) after being fully informed about the exposure to radiation. It’s also crucial that the doctor knows if the patient has any allergies. If contrast dyes are going to be used to improve the images, the patient’s kidney function should be checked. For women who can still have children, it must be confirmed that they are not pregnant. Also, if the C-arm, (a piece of equipment that supplies the x-rays), is going to be used during surgery, its surfaces should be kept clean to avoid any infections.
How is Fluoroscopy Orthopedic Assessment, Protocols, and Interpretation performed
Getting a high-quality image while reducing the amount of radiation exposure to both the patient and the surgeon during a medical procedure is crucial. Here we will discuss how to decrease radiation exposure while still maintaining a clear image.
The primary beam is the main source of radiation for the patient, and the scatter is the source of exposure for the surgeon and operator. Fluoroscopy systems have different settings that regulate the amount of radiation and adjusts the image quality. For instance, you can adjust the voltage used to create the x-rays (measured in kilovolts or kV), the current flowing through the x-ray tube (measured in milliamperes), and the time that the radiation is released (measured in milliseconds). Higher voltage settings allow the x-ray machine to use a lower current, which means less radiation exposure.
The imaging device should be as close to the patient as possible. This ensures the x-rays don’t scatter and less radiation is required to get a sharp image. But sometimes, using a device that blocks scatter can slightly increase the total radiation dose. So, there has to be a balance. Using pulsed (on-and-off) radiation instead of continuous radiation can reduce radiation exposure by up to 76% and the time the patient is exposed by 64%. The more we decrease the image capture rate, the less radiation is used. Collimation, which is a technique that narrows the x-ray beam, should be used whenever possible.
Magnification increases the radiation dose and the scatter, which is radiation that comes from directions other than the x-ray. Magnifying the image can often be avoided by using things like digital zoom and large displays. Communication between the surgery team and the technicians who operate the x-ray machine is also very important.
Joint Injections Under Fluoroscopic Guidance are usually done under strict sterile conditions. You have to properly position the patient before the procedure to make sure the doctor can safely and efficiently access the joint, and the patient is comfortable. A plastic or metal object that shows up on the x-ray is used to mark where to insert the needle. The doctor will clean the area with a sterilizing solution, then numb the skin and the path the needle will take with a local anesthetic. The needle is slowly advanced into the joint, and the doctor will often verify the needle placement with the x-ray.
The doctor will usually be able to tell what the needle is touching, but the x-ray is a helpful guide. Once the needle is in the joint, the doctor will blow a little air into the joint or fill the joint with a little saltwater (saline). If the needle is properly positioned, the contrast medium will flow into the joint without any resistance. If the needle is intra-articular, meaning inside the joint, then the contrast medium, a substance that helps improve the quality of the imaging, will flow into the joint spaces instead of clustering around the needle-tip.
Patients get joint injections for various reasons. Sometimes, doctors use them to see if there is a tear in the fibrocartilage complex, which is located between the wrist bones, or in the ligaments inside the wrist. Other times, they inject therapeutic medications such as steroids, hyaluronic acid, platelet-rich plasma, etc.
Each joint has specific access points which may vary depending on the procedure and patient’s condition. They include the shoulder, elbow, wrist and hips. For instance, the shoulder joint can be approached from the front (anteriorly) or back (posteriorly). The injection point will depend on the specific goals of the procedure, potential risks, and other relevant factors. Throughout the process, the doctor relies on the fluoroscopy system to provide live images, ensuring accurate needle placement and minimizing any associated risks.
What Else Should I Know About Fluoroscopy Orthopedic Assessment, Protocols, and Interpretation?
Being injured while pregnant can happen in a variety of ways—such as car accidents or falls—and it’s one of the top reasons for serious health problems in pregnant women. The safety limit for a fetus’s exposure to radiation is around 5 cGy. At this level, the risk to the developing baby is less than the naturally occurring risks faced by all unborn babies. Interestingly, it’s been noted that when a pregnant woman’s thyroid is exposed to diagnostic radiation, the baby’s birth weight might be slightly less.
When it comes to diagnostic imaging during pregnancy, here are some guidelines:
1. Women should be informed that the radiation from a single diagnostic procedure isn’t likely to harm the baby in the womb.
2. Specifically, exposure to less than 5 rad doesn’t increase the chances of birth defects or pregnancy loss.
3. Fear about high levels of radiation should not stop needed diagnostic tests from being done during pregnancy.
4. Imaging procedures that don’t include any radiation should be considered as a first choice when they are appropriate.
5. Radioactive types of iodine should not be used when pregnant.
6. Certain contrast agents, which help images show up more clearly, are unlikely to cause harm and may offer diagnostic benefits.
There have been some recent advancements in medical imaging. This includes components that automatically adjust the image’s sharpness and contrast, no matter the exposure, and provides a continuous view in pulsed fluoroscopy. It even offers a real-time radiation dose display for the surgeon to monitor exposure.
New flat-panel detectors have greatly improved medical imaging—they offer high-quality images and less radiation exposure compared to a standard C-arm. These mobile C-arms reduce the dose of radiation during the operation, provide a larger view of images due to a larger detector, and improve the resolution of soft tissues. The distance from the source to the image increases, offering the surgeon a larger workspace with less scattered radiation.
Three-dimensional (3D) imaging during operations can ensure a good reduction of fractures in situations where the joint surface is not completely visible in 2D imaging. This is specifically helpful in joints like the hip socket or irregularly shaped bones like the heel bone. Cone-beam CT is a 3D data set that can be used with a flat-panel detector. It takes numerous images that are converted to 3D images with the help of computers. This kind of imaging is really valuable for reconstructing complex joint fractures during surgery. It helps control the reduction of the fracture and the implant positioning with high image quality, reducing the need for repeat surgeries. The O-arm, an intraoperative navigation system, significantly reduces the rate of malpositioned screws in the spine and improves placement of screws in the hip bone.
