Stroke Symptoms

The brain receives its blood supply through the left and right carotid arteries and vertebral arteries branching from the aorta. Blood vessels that supply each area of the brain are distinguished by region, and because each area has a different function, the symptoms can vary greatly depending on which blood vessel caused the problem and the location and extent of the damaged brain tissue.

Meanwhile, stroke may cause severe symptoms immediately, leading a person to go to the emergency room, but some people have vague symptoms and visit the hospital only months later. In some cases, people visit for other neurological problems such as dizziness, movement disorders, epilepsy, or dementia, and brain imaging reveals a cerebral infarction.

The representative early symptoms that should raise suspicion of stroke include hemiplegia, speech disorder, visual disturbance, dizziness, and severe headache.

1. Hemiplegia

The motor nerves that start from the motor cortex of the cerebrum and descend to the arms, legs, and face cross in the medulla as they travel downward from the cerebrum. Therefore, if a lesion develops in a blood vessel on one side of the brain and blood supply is interrupted, sudden paralysis occurs in the arm, leg, and lower face on the opposite side.

2. Sensory abnormalities and loss of sensation

All sensations of the skin, such as pain, temperature, and touch, are transmitted through peripheral nerves to the spinal nerves, and in the spinal cord, the sensory nerves also cross to reach the opposite thalamus and the brain areas responsible for sensation. Therefore, if there is a problem with the function of one side of the brain, abnormalities occur in the sensation of the face, trunk, and limbs on the opposite side, causing feelings such as numbness or an unpleasant sensation as if it were someone else’s flesh, and the senses of touch or pain may also be reduced.

3. Headache and vomiting

As the first symptoms of stroke, severe headache followed by repeated vomiting and then impaired consciousness is often seen, which occurs because intracranial pressure increases. Headache and vomiting occur more often in hemorrhagic stroke than in ischemic stroke. In particular, a headache caused by a ruptured aneurysm may suddenly begin as an intense headache, as if the head were struck hard with a hammer, and the patient may lose consciousness.

4. Dizziness (vertigo)

This is a symptom that can occur when blood supply to the cerebellum, which is responsible for balance, and the brainstem connected to it is insufficient, and it is accompanied by nausea and vomiting, making it difficult to maintain balance.

Dizziness caused by stroke is often difficult to distinguish from dizziness caused by diseases of the inner ear, but in stroke it is often accompanied by other clinical symptoms such as impaired consciousness, paralysis of one arm and leg, and sensory loss, which makes it distinguishable.

5. Speech disorder (aphasia)

The ability to speak fluently and understand others when listening is mainly controlled by the left cerebrum.

In fact, because the language center is located in the left cerebrum in 90% of right-handed people and 70% of left-handed people, speech disorders are often accompanied by paralysis of the right side of the body.

The language center includes the motor center for speech and the sensory center for reading letters with the eyes or listening and understanding with the ears. Because these areas are supplied by different blood vessels, depending on the affected vessel, motor aphasia or sensory aphasia may appear.

6. Articulation disorder (dysarthria)

Unlike a speech disorder, articulation disorder means that a person can speak, but because the lips or tongue do not move properly, clear pronunciation becomes difficult.

7. Facial nerve paralysis

If the area of the brain responsible for the facial nerve is damaged, the facial nerve that controls movement of the facial muscles becomes paralyzed. In this case, the mouth is pulled toward the unaffected side, and the eye on the paralyzed side does not close well. These symptoms are often accompanied by hemiplegia.

8. Ataxia

This means that although arm and leg strength is normal, the person staggers like someone who is drunk and tends to keep falling to one side,

or cannot grasp objects accurately and keeps missing them when trying to pick them up. This suggests an abnormality in the cerebellum or brainstem.

9. Visual disturbance / visual field defect

Objects seen with the eyes are transmitted through the retina, optic nerve, and optic tract to the visual center of the occipital lobe, and only then does a person recognize what is seen, thinking, “Ah! So this is what it is.” If stroke causes a problem anywhere in this process, visual disturbance or a visual field defect occurs.

10. Diplopia

Diplopia means seeing one object as two. This occurs when a disorder develops in the part of the brain that moves the eyeballs, causing the axes of both eyes to become misaligned. As a result, the image of the object forms on different parts of the two eyes. This is mainly a symptom that appears when oculomotor nerve paralysis occurs in brainstem infarction.

11. Dysphagia

This is a symptom in which it becomes difficult to eat food or swallow water, and it can occur when there is infarction of the brainstem or both cerebral hemispheres.

Patients with dysphagia frequently choke, causing swallowed food to enter the bronchial tubes, which can lead to aspiration pneumonia. Aspiration pneumonia is a relatively common complication in stroke patients with dysphagia, and because it is a major cause of death in stroke patients, care is needed.

12. Coma

If a stroke occurs in the brainstem, which is the center of consciousness, or in a fairly large area of the cerebrum, consciousness gradually worsens and the patient falls into a coma, often accompanied by other neurological abnormalities.

13. Dementia-like symptoms

If the area of the brain responsible for intellectual abilities such as memory, calculation, and judgment is damaged, dementia-like symptoms can occur.

14. Transient ischemic attack

The stroke symptoms described above may disappear within 24 hours of onset; this occurs when blockage of a cerebral blood vessel is temporary and then resolves on its own. This is the so-called "transient ischemic attack," also called a "mini-stroke." Although the symptoms disappear and the person appears normal, the inner wall of the blood vessel is significantly narrowed, so if proper diagnosis and treatment are not performed, there is a risk that an actual stroke will occur soon. Patients suspected of having a transient ischemic attack must be examined by a doctor to identify the risk of stroke in advance and prevent it.

So far, I have explained the symptoms of stroke.

In the next part, we will look at the diagnosis of stroke.

Source: Korea Disease Control and Prevention Agency National Health Information Portal