MRI Guide: What is an Orbit MRI Scan?
Our eyes let us interact with the world around us. Changes in our vision can be an important indicator that something is going wrong. This can come in the form of a sudden loss of vision, prolonged periods of blurred vision, or pain. The eyes are housed in what is called the orbit. If you have experienced eye pain or changes to your vision it can be a sign of a neurological issue, an eye disorder, or even a fracture to the orbit.
Since the head is made up of a complex series of organs, tissues, bones, and muscles, it can be hard to identify the root of the problem through traditional observation techniques. An MRI scan provides the insight needed to identify the cause of a potential issue. In this article, we will discuss what an orbit is, what an MRI orbital scan entails, and how to prepare for the procedure.
What is an Orbit?
An orbit refers to the boney cavity occupied by your eye, nerves, muscles, fat, and additional soft tissues needed for proper eye movement and function. They are symmetrical and separated by the nasal cavity and paranasal sinuses. An orbit MRI scan is sometimes also referred to as an orbital MRI scan.
The orbit itself is a pyramidal structure, the wide base of which is the open cavity and narrows like a cone behind our eyes. It is comprised of seven bones,
Together these bones form the base, and walls of the orbit. The walls provide eye protection from blunt force trauma, as well as a place for the orbital muscles to connect. There are seven small muscles inside each orbit responsible for proper eye movement. These include:
- Levator Palpebrae Superioris
- Superior Oblique
- Inferior Oblique
- Superior Rectus
- Inferior Rectus
- Medial Rectus
- Lateral Rectus
These muscles work together to control your eye movements within the orbit.
What Does an MRI Orbit Scan Show?
A Magnetic Resonance Imaging (MRI) orbit scan will show:
- Bones of the Orbits
- Optic Nerve
- Blood Vessels
- Fat Deposits
Radiologists will use the images produced by the scan to diagnose optic diseases such as optic neuritis which causes inflammation of the optic nerve. This inflammation can also be an early sign of Multiple Sclerosis (MS).
The scan will also be able to indicate the presence of:
- Optic Neuropathy
- Any Additional Trauma
These issues can cause a variety of vision problems, pain, and can be a sign of more severe degenerative diseases. If you are experiencing any abnormal changes to your vision, it’s important to contact your doctor. An MRI can provide a clear image as to what is occurring inside the orbit, resulting in earlier medical intervention.
What to Expect From an MRI Orbit Scan?
An MRI orbit scan is similar to a head or brain MRI scan.
Removing Metal and Changing
Most MRI clinics will have you change into a hospital gown before your procedure. This is to ensure there is no conflict with your clothing and the MRI machine. However, some centres will allow you to wear your loose-fitting clothing, free of metal clasps and zippers, that provides easy access to the body part being scanned.
Piercings, metal jewellery and other metal objects will need to be removed. Metal will interfere with the machine producing obscured images.
Positioned on MRI Table
A radiographer will bring you into the MRI room and have you lay down on the table. They will most likely use a device to keep your head in place. This might be a foam block, strap, or pillow. This is common practice however, the method used to keep your head in the correct position may vary based on each facility.
Get Contrast IV
During a brain or head MRI scan, it is not always necessary to use a contrast IV material. However, during an orbit MRI scan, this is a necessary step. The contrast material is needed to fully visualize the optic nerve. The radiographer will place the IV in your arm or hand, you will feel a warm sensation running through your body. This is a normal reaction and the feeling will fade away.
It is important to stay as still as possible, and only move if directed by the technician. The machine will make loud banging noises, this is to be expected. This can make it difficult to not move, but try your best to remain as still as possible. Any sudden movements can result in poor image quality, causing the need for a repeated scan to be taken. If for any reason you begin to feel uncomfortable, inform the technician and they will do their best to adjust the procedure to make you more comfortable.
Have Contrast IV Removed
Once the scan has been completed and the radiographer is satisfied with the images, your IV will be removed. There are no side effects to this procedure, however, you may feel a little dizzy after lying down for a while. Therefore take caution when standing up.
The technician will bring you back to a private room where you can change and go about your daily activities.
How to Prepare for an Orbit MRI Scan?
Each facility has its policies on eating and drinking before an MRI procedure. Typically it is not necessary to fast before an orbit MRI scan unless otherwise advised.
Before your scan, you will be asked about your medical history. It is important to disclose:
- Pacemaker, or Defibrillator - the magnetic field can affect the settings of these devices therefore their performance needs to be monitored.
- Allergies to Medication or Contrast Material - to avoid a potential reaction the radiographer can use different materials or medications for your scan.
- Metal plates or Artificial Joints - these can potentially cause blurred images, therefore the technician may have to adjust their scanning technique to work around these objects.
- Ear or Eye Implants - an orbital MRI scan is directly focused on this area, any foreign objects need to be disclosed to ensure the radiographer can still obtain the necessary images while working around these objects.
- Hearing Aids - these can be easily removed before the procedure, but it’s recommended to inform the technician to ensure they are not forgotten to be taken out.
This is important to ensure the MRI can be performed safely. You should also disclose if you are pregnant. There has not been any link between MRI and birth defects, however, it is still important to inform the radiographer before your procedure.
What Happens After an MRI Orbit Scan?
Since an MRI orbit scan is a non-invasive procedure, there is no recovery or downtime. Once the scan is complete you are free to go about your daily activities. Some patients require a mild sedative to ease anxiety about the procedure. If this was the case for you, the sedative will take time to wear off, you should avoid operating a vehicle during this time.
In the days following your procedure, a radiologist will examine the images from your scan. Once they have interpreted the results they will forward them to your doctor. Your doctor will then contact you to discuss the results and a treatment plan if required.
Experiencing pain or sudden changes to your vision can be scary. It’s important to contact your doctor to discuss any concerning symptoms. An MRI orbit scan can help identify the cause of your vision loss or pain, allowing for quick medical intervention.
If you want to have your MRI scan without waiting for the NHS, consider booking an appointment at one of our centres. We can schedule an appointment in as little as 5 working days, ensuring you can get back to enjoying your everyday life as quickly as possible.