Magnetic resonance imaging (MRI) scan is a diagnostic assessment tool used to visualise your body's internal structures comprehensively. In the case of the brain and spine, an MRI is preferred as it has superior capabilities of detecting abnormalities with a sensitivity rate of 90% and a specificity rate of 85%. Undoubtedly a preferred imaging tool in neurology and neurosurgery practice, an MRI is often instrumental in the early detection of various brain and spine conditions, allowing for prompt intervention and increasing chances of recovery.
Unlike X-rays and CT scans, MRI scans are advantageous as they do not emit ionising radiation to obtain detailed images of the brain and spine. This is particularly valuable in cases where patients are pregnant or young (children), as reducing radiation exposure is prioritised.
Additionally, MRIs enable images of internal organs to be produced on multiple planes, providing the most accurate visualisation of bodily structure from different points of view;
MRI scans work with the magnetic field around the human body by sending a burst of radiofrequency waves, which in turn signals into a picture on a computer. As the human body is mainly made up of water, an MRI fundamentally maps out hydrogen atoms in the body, subsequently providing precise and detailed images of the brain and spine. The signal emanated by each cell in the human body during an MRI enables the production of detailed images with the ability to distinguish various tissue types.
During a brain and spine MRI scan, you will be positioned on a scanning table that slides into the MRI scanning machine. You may be strapped or provided pillows to prevent excessive movement. Once in the machine, you will be in contact with the technologist in the event you require assistance. For patients with general difficulty staying still (pain from injury, anxiety, or claustrophobia), you may be offered anaesthesia as a sedation until the procedure is complete. You may be injected with a dye to visualise the bloodstream better, but this is subjective to the patient’s case. An MRI scan may take between 30 minutes to 2 hours, depending on the specific query of medical investigation.
MRI scans can detect abnormalities that may otherwise be evasive in CT scans and X-rays. Conditions and abnormalities that an MRI scan can detect include:
Fundamentally, a brain and spine MRI scan can help detect the presence of any tumours, degeneration, structural abnormalities, compression of nerves and issues pertaining to soft tissues. It is a gold standard for diagnosis as spinal and brain tissues are often complex and require detailed investigation.
Upon identification of your issue, your neurosurgeon will provide a comprehensive explanation of the findings, followed by the appropriate diagnosis. A treatment plan will also be recommended to relieve your symptoms and build a pathway towards recovery. The consultation may also comprise medical prescription and lifestyle changes that should be incorporated to ensure your condition is not exacerbated.
Typically, a single session is sufficient for diagnosing and identifying anomalies in your brain and spine. You may also be recommended an MRI scan to monitor your condition within a specific time frame. When MRI is used as a monitoring tool, your neurosurgeon can gauge if the treatment introduced is successful or if other treatment modules need to be explored.
If you cough, sneeze, or swallow during an MRI, the scan must be repeated. Instead, you may inform the technician to pause the scan through the established communication method (through a speaker, button, or bell). You will not be scrutinised if you accidentally move during an MRI. We know staying still for long periods can be uncomfortable, and we are ready to guide you accordingly. However, if the scan is expected to take a long time (over 30 minutes), we may recommend anaesthesia to reduce levels of discomfort.
You may close your eyes, but you are advised against falling asleep as you may unconsciously twitch and move while sleeping.
An MRI cannot be conducted on patients with cardiac implantable electronic devices (CIED), intracranial aneurysm clips, and cochlear implants. However, these conditions are not rigid. Newer implants and devices that are implanted in the body are usually MRI-safe. Thus, it is important to declare all aspects of your medical history to your neurosurgeon during consultation to minimise risks.
MRI and CT scans are valuable diagnostic tools, and it would be inaccurate to claim one is superior. CT scans are pertinent in cases of emergency and where urgent diagnosis is required. An MRI does provide more detailed imaging with reduced obstruction; however, the duration of the procedure may be unsuitable for some patients. Additionally, MRIs are also limited where patients are physically larger. Additionally, in many cases, a CT scan is sufficient to diagnose and treat conditions.
It is best to leave the selection of diagnostic tools to a medical provider. Rest assured, the best tool will be recommended with your best interest in mind.