Depending on how long circulatory disturbances in the brain last and how severe these disturbances are, different signs and symptoms occur in the context of a stroke. There are smooth transitions between temporary, fleeting symptoms as well as permanent neurological deficits.
Different gradations
In principle, a distinction is made between several stages in relation to a stroke:
- TIA (transient ischemic attack): here the circulatory disturbance in the brain exists only for a short time; complaints such as visual disturbances, speech disorders, numbness or dizziness occur only fleetingly and disappear again after seconds to minutes. This is comparable to a temporary attack of pain (angina pectoris) in coronary heart disease, i.e. the narrowing of coronary arteries. As there, such temporary discomfort are also signs of a disturbed blood flow situation – which can lead here in a stroke, at the heart in a heart attack.
- PRIND (prolonged reversible ischemic neurologic deficit): here the intensity and duration of the symptoms are stronger; deficits can last for hours or even days, but then completely recover. The transition to a “major” stroke is fluid.
- Insult: Manifest stroke. Scar tissue forms in the area of the destroyed brain substance. Neurological damage often remains for the rest of life.
Stroke: recognize signs
The function and structure of the brain are very complex; accordingly, a wide variety of combinations of symptoms are possible. Symptoms or failure symptoms as signs of a stroke give the doctor clues about the affected vessel or brain area. The afferent and efferent nerve fibers that connect the brain to the rest of the body cross in the lower part of the brain, the brain stem. Therefore, when a stroke occurs in the cerebrum, symptoms appear in the opposite side of the body: if a stroke occurs in the left side of the brain, the right side of the body is affected, and vice versa. If a stroke is in the brainstem area, both halves of the body can be affected because many conduction fibers for both halves of the body and control centers are also close together here and thus can be affected equally.
Typical symptoms of stroke
The following is a selection of typical symptoms of stroke:
- Vascular occlusion of the middle cerebral artery (arteria cerebri media), which supplies part of the cerebrum (c.80 percent of vascular strokes): sensory disturbances and paralysis on the opposite side of the body, most pronounced in the fingers and face; sometimes also loss of vision in opposite side of face
- Vascular occlusion of the posterior cerebral artery, which also supplies part of the cerebrum (c.a. 10 percent of vascular strokes): loss of vision in opposite visual field, disturbances of consciousness and sensation on opposite side of body
- Vascular occlusion of the anterior cerebral artery, which also supplies part of the cerebrum (c.a. 5 percent of vascular-related strokes): hemiplegia on opposite side, affecting the leg more than the arm
- Vascular occlusion of one or more of the numerous brainstem vessels (20-50 percent of all vascular strokes): visual disturbances, locomotor disturbances, sensory disturbances, back of the head pain, twitching of the eyeballs, unsteadiness when walking, speech disturbances and, in severe cases, clouding of consciousness
Stroke diagnosis
The diagnosis of stroke usually results already from the typical picture of immediately new neurological deficits. If the symptomatology is only slightly pronounced, such as mild sensory disturbances of a hand or sudden visual disturbances, other clinical pictures are also included in the diagnosis. Evidence of a circulatory disorder in the brain can be provided by computer tomography or magnetic resonance imaging (MRI). This allows the type of damage and the affected area of the brain to be determined more precisely – which is also not insignificant for therapy or treatment.Additional information for diagnosis may be provided by ultrasonography, imaging of the cerebral circulation, injection of contrast media, examination of the heart for potential sources of emboli, and examination of the blood for potential clotting disorders.
