Several MRI abnormalities on conventional MRI already are included in the current diagnostic criteria for MSA along with abnormalities of functional neuroimaging, including 18F‐flurodeoxyglucose positron‐emission tomography (FDG‐PET) and presynaptic dopaminergic imaging.
Brain imaging scans, such as an MRI , can show signs that may suggest MSA and also help determine if there are other causes that may be contributing to your symptoms. You may receive a referral to a neurologist or other specialist for specific evaluations that can help in making the diagnosis.
Expected MRI findings in MSA are as follows: Atrophy of cerebellum and brainstem in OPCA and striatonigral degeneration (SND) No vascular damage. No multi-infarct pattern in brain.
Multiple system atrophy (MSA) is a rare condition of the nervous system that causes gradual damage to nerve cells in the brain. This affects balance, movement and the autonomic nervous system, which controls several basic functions, such as breathing, digestion and bladder control.
Diagnosing MSA
Magnetic resonance imaging (MRI) may identify changes that suggest MSA or rule out other causes of the symptoms. Positron emission tomography (PET) scans can be used to monitor metabolic function in specific parts of the brain.
The presence of α-syn within oligodendrocytes in the form of glial cytoplasmic inclusions is the diagnostic hallmark of MSA.
What are the symptoms of MSA? Most often, the first clinical symptom a patient will note will be lightheadedness, dizziness, and episodes of passing out, but the first symptoms in some patients may include difficulty initiating movement, body stiffness, urinary incontinence, and increased falls.
MSA causes deterioration and shrinkage (atrophy) of portions of your brain (cerebellum, basal ganglia and brainstem) that affect internal body functions and motor control.
Red flags supporting the diagnosis of MSA include the following: Orofacial dystonia. Disproportionate antecollis. Severe anterior flexion of the spine (camptocormia)
The diagnostic accuracy was 71% in probable MSA and 60% in possible MSA. Correctly diagnosed patients with MSA had a younger age at onset and age at death than patients with PD or PSP, but duration of symptoms did not differ.
Basic Principles for Muscle MRI
The T1-weighted images can be used to assess muscle anatomy; detect fatty infiltration, which reflects remote damage and muscle loss; and crudely assess muscle volume for atrophy or hypertrophy.
Atrophy can be measured from brain MRI scans, and many technological improvements have been made over the last few years.
The presence of chronic MS lesions in the brain has associations with disability and brain atrophy. In a T1-weighted MRI scan, permanently damaged areas of the brain appear as dark spots or “black holes.”
PD and other atypical parkinsonisms, such as DLB and PSP, are usually considered to be the main culprits of an MSA misdiagnosis, but many other diseases can mimic MSA [3, 4]. Brain MRI is a key element when evaluating parkinsonian and cerebellar syndromes [22].
MSA damages the nervous system. The disease tends to progress rapidly. About one half of people with MSA-P have lost most of their motor skills within 5 years of onset of the disease.
Though dementia is not considered a common characteristic of MSA, cognitive impairment occurs in some patients in the form of loss of verbal memory and verbal fluency1.
Blood Tests
Individuals with MSA have near normal levels of a neurotransmitter called norepinephrine, which is used in the autonomic nervous system. This chemical is often decreased in PAF, and is used in some centers for diagnosis of PAF (peripheral)5. There are no diagnostic blood tests for MSA at present.
We found that 30 MSA patients (46.15%) suffered from pain. There was a trend towards a higher prevalence in MSA-P compared to MSA-C patients although the difference was not significant, which might be due to the small sample size. Few studies have investigated the pain mechanism in MSA patients.
Further work has demonstrated that the skin vasomotor response to local heating is intact in MSA patients, with the cold hand sign suggesting preserved sympathetic tone to the hands. Intact sympathetic tone may manifest as vasoconstriction but also as sweating.
Sleep disorders in patients with MSA include rapid eye movement sleep behavior disorder (RBD), excessive daytime sleepiness (EDS), and nocturnal sleep disturbances.
This explains why some symptoms of MSA such as a tremor or speech difficulty can seem temporarily worse in stressful situations. Feeling anxious and worried is a familiar feeling for many people affected by MSA and it can easily become an unhelpful cycle.
Typical ocular features of MSA include blepharospasm, excessive square-wave jerks, mild to moderate hypometria of saccades, impaired vestibular-ocular reflex (VOR), nystagmus and impaired event-related evoked potentials.
The peak onset of MSA is between 55-60 years of age, with a range from 30 to over 90 years. The incidence of MSA in the United States is estimated at 0.6 cases per 100,000 people per year in the general population giving a current estimate of about 1,900 new cases per year in the USA.
Parkinsonism symptoms with MSA-P often start on one side of your body and then spread to both sides. These symptoms usually involve the following: Slowed movements (bradykinesia). Stiffness and rigidity when moving, causing a hunched-over posture.
In MSA there may be several stages -- alpha-synuclein accumulates in the oligodendroglial cells, then there is failure of mitochondrial function as well as loss of trophic factor support. Then the oligodendroglia degenerate, followed by microglia and astroglial activation. alpha-synuclein misfolds in MSA.