By the end of this e-learning resource, you should be able to:
Multiple sclerosis is a chronic, demyelinating disease of the central nervous system (brain and spinal cord). The upper motor neurones (UMN) are located here meaning that this a UMN disease. As a result there is a disruption of information between the brain and the body leading to a variety of presentations.
Key learning point: Multiple sclerosis is an upper motor neurone disease
There are two main types of multiple sclerosis: progressive and relapse-remitting.
Relapse-remitting MS is generally regarded as the 'better form' of MS, because it comes and goes in waves and often doesn't cause permanent and progressing disability.
Progressive MS becomes gradually worse over time with permanent damage to the neurone's myelin sheaths, hence causing increasing life-long disability.
There are two sub-types of progressive MS. Primary progressive MS occurs right from the start, whereas secondary progressive describes a relapse-remitting form that eventually converts into progressive (see graph).
Key learning point: MS comes in relapse-remitting and progressive forms
Common manifestations of multiple sclerosis that you might see in an ISCE setting or as an F1 include:
Other unexplained neurological symptoms that are specific to that of upper motor neurone pathology
A full neurological examination of a patient with suspected MS could yield these findings:
Changes on sensation, especially patchy in random areas of the body
Internuclear ophthalmoplegia (INO)
Multiple sclerosis is diagnosed using the McDonald criteria:
1. Dissemination in time: Neurological symptoms must have presented in at least two different parts of the body
1. Dissemination in space: Neurological symptoms must have occured at different points in time
An MRI scan is the imaging method of choice in helping confirm a suspected diagnosis of multiple sclerosis.
This is done with an enhanced form of T2 imaging called a FLAIR (fluid attenuated inversion recovery). As suggested by its name, this causes the CSF fluid to be darkened whilst still maintaining the other parameters of a T2 scan.
This is done because MS lesions are most often seen around the ventricular borders in the brain. If the CSF fluid wasn't darkened, there wouldn't be an easy way to distinguish between an MS lesion vs the CSF. T1 scans aren't used for this because, while it would darken the CSF, it would also darken the MS lesions, rendering it useless for an MS diagnosis. Hence, T2-FLAIR is the preferred method.
Here are some T2-weighted MRI images of a brain with MS lesions near the ventricles. Notice how, while you can see the white MS lesions clearly, the CSF in the ventricles also appeaer bright white and can act as a distraction. The next page will show you how these differ from FLAIR images, and you'll see why they are easier to see MS lesions in.
Black arrows showing juxtacortical MS lesions when taken with a gadalinium contrast
T2 MRI showing enhancing infeatentorial lesions on the pons
Sagittal view of the spinal cord showing enhancing lesion at C3/C4 suggestive of MS
Now some FLAIR images. See how the ventricles appear dark while the MS lesions in the brain still appear light. This should make it easier to detect the demyelinating lesions of MS:
FLAIR image showing Dawson's fingers. These are periventricular plaques that you can see in this saggital view that indicates MS demyelinating zones
Alongside the usual history and presentation structure that you already know (we won't go over the fundamentals again here), you'll need to make sure you comment on these findings:
There is no cure for multiple sclerosis. Management involves reducing the frequency and duration of relapses, with the view to delay the inevitable disability that would result due to the disease.
Key learning point: MRI scans are the preferred imaging modality of choice for anything spine and neurological related
These are T1 weighted MRI images. CSF does not contain fat, and hence appears dark.
These are T2 weighted MRI images. The CSF here now appears white. However, don't get confused with CSF vs the spinal cord itself, which still appears dark
In the Year 4 ISCE, the main expectations from you with regards to brain MRI scan interpretations are:
1. Verify patient details
- Name, DOB and hospital number
1. State the obvious
- What type of image is it and what part of the body? MRI brain
- What plane? Sagittal, axial, coronal
- Is it T1 or T2?
- Say that you would compare to any previous images
2. State the most obvious abnormality and its location
3. Identify key anatomical structures
In your ISCE, it’s likely that you will face a patient with back pain, as this presentation warrants many urgent investigations to exclude worrying differentials. If you encounter any of these red flags, act immediately:
Geeky Medics has a useful mneumonic to help remember these:
TUNA FISH
Let’s talk about some of these symptoms in context of the condition we’re worried about:
You are very likely to be tested on these in the ISCE, especially in the data interpretation stations. Click Next to take you through some scans...
1. Normal Saggital T2 MRI Lumbar Spine
2. Cauda Equina Syndrome
3. Spinal Metastases Causing Compression
4. Thoracic Spine Fracture Causing Compression
5. Lumbar Disc Herniation
Top tips for your ISCE examination:
Parkinson’s Disease is a high-yield condition in Medicine, commonly seen in your placements and tested in your examinations. Having said that, it’s important to have a good grasp of its presentation, diagnosis and management for not only your programme, but also because it’s getting increasingly prevalent in our growing older population.
Let’s categorise Parkinson’s disease to understand where it fits into neurology. It's crucial to emphasise, first and foremost, that this is a neurodegenerative condition. It is chronic, and progressive, so will unfortunately worsen over time. In your ISCEs, remember that if you are suspecting a patient to have this condition, you mustn’t forget that this is a situation to break bad news, as all you can do is slow down the progression, not cure it. Apply all your important soft skills: listen actively, give pauses, comfort any relatives, etc.
Parkinsonism is a group of symptoms, which we’ll outline now as:
Bradykinesia and at least one of:
Tremor
Rigidity and/or postural instability
Parkinson’s disease is the most common type of parkinsonism. Other types include drug-induced parkinsonism, dementia with Lewy bodies, progressive supranuclear palsy and multiple system atrophy. Each condition has overlapping symptoms, since they all come under Parkinsonism, but have stark differences, which I will briefly mention now for your interest on the next page.
A typical clinical presentation:
"A 65-year-old male presents with a history of bradykinesia, unilateral resting tremor and cogwheel rigidity. He walks with a shuffling gait, writes in very small handwriting, and has diminished facial expressions. During your history-taking, you discover that he has also been experiencing low mood and vivid dreams. He is constantly exhausted and finds it difficult to cope with."
Patients may also experience autonomic dysfunction, for example, postural hypotension.
Diagnosis:
If you suspect this condition, you are required to refer your patient urgently to a specialist in movement disorders for diagnosis.
Diagnosis is mainly clinical, however, if the patient’s tremor is difficult to differentiate from an essential tremor, a 123I-FP-CIT single photon emission computed tomography (SPECT) may be considered. This is a type of SPECT scan, called a DaTscan, which is more useful for detecting the loss of dopamine than an MRI brain. The latter usually appears normal in Parkinson’s.
For the purposes of showing the neuroradiology of this condition, we will take a look at the DaTscan:
This scan works via radioactive tracer which attaches to a dopamine transporter in the neurones. A gamma camera is then used to pick up the gamma rays from the tracer. In your patient’s imaging, you will be able to see that there is a loss of dopamine and consequent neurodegeneration.
Initial management:
Admit your patient to secondary care if unstable.
Patients with confirmed Parkinson’s are required to be managed with a specialist MDT including nurse specialists for monitoring.