Posterior Cerebral Artery Syndrome
Posterior Cerebral Artery Syndrome is a type of stroke that affects the rare of the brain. Literally meaning the ‘back end’, the posterior side of the brain is supplied oxygenated blood by the Posterior Cerebral Artery. A reduction in the function of this part of the brain leads to Posterior cerebral artery syndrome, which is characterized by a number of signs and symptoms discussed in later topics.
Understanding posterior cerebral circulation anatomy is elemental to appreciating the implications of posterior cerebral artery syndrome. The brain, as a whole, is a mass of neurons and tissues that act together to control voluntary and involuntary activities of the body. To make this coordination process effective and seamless, it is divided into many sections.
Compartmentalization is a key feature of the nervous system because it enables the brain to regulate different parts of the body in various ways, and at the same level of efficacy. It provides guidelines for the neurons to pick up and deliver messages in their respective control centers. Posterior cerebral circulation anatomy is a part of brain compartmentalization in which the anterior cerebral artery is responsible for the front, while the posterior cerebral artery caters to the back.
The Posterior Cerebral Artery Territory
A PC stroke happens when there is a blockade in the Posterior cerebral arteries. Such a blockade can be in the form of hard plaque that is made up of cholesterol, fat cells, debris and calcium. At times, this obstruction originates in the artery under question; and at other times, it travels in the circulating blood from other parts of the body and gets lodged in the smaller posterior cerebral arteries.
The posterior cerebral arteries penetrate deep inside the mass of the cerebellum to form a well-knit sensory network. A blockade in any one of the vessels can disrupt the supply of blood flow to the entire posterior region. Even a few minutes without fresh blood can be fatal for the sensitive neurons that suffer damage and can die approximately six minutes after oxygen deprivation.
Therefore, a patient is said to suffer from this syndrome when the posterior artery fails to supply adequate blood to Posterior cerebral artery territory. This territory includes:
The Occipital Lobe: The visual processing centre of the brain that analyzes images that the eyes see.
The Inferomedial Temporal Lobe: Emotional associations, language comprehension and visual memory centre.
A large part of the Thalamus: This controls consciousness, sleep and alertness of the mind and body.
The Upper Brainstem: Sensory intervention for the face and neck.
The Midbrain: Temperature regulation, vision, hearing and motor control centre.
The above regions that define the Posterior cerebral artery territory make it clear that any trouble in the supply of blood flow to these areas can be catastrophic for the human body. Their main functions highlight how important these centres are for a complete and thorough communication between the brain and the rest of the body.
Symptoms of Posterior Cerebral Artery Syndrome
A PC Stroke is a type of ischemic stroke. Its onset and implications are no different from any other type of stroke in the brain. However, the posterior region of the brain controls a number of essential activities in the body, all of which are severely affected when the posterior cerebral arteries are blocked. Symptoms of Posterior Cerebral Artery Syndrome surface when pressure builds in the upstream of the vessel because of the obstruction. Depending on the extent of the occlusion in the arteries, the severity of a PC stroke varies from patient to patient.
Since there are so many regions in the posterior cerebral artery territory, all the symptoms of Posterior Cerebral Artery Syndrome may not show in every patient at the same time. If a patient has more obstruction towards the occipital lobe than the thalamus, there will be more trouble with vision than alertness.
Generically speaking, the following are some prominent symptoms of Posterior Cerebral Artery Syndrome:
• Acute loss of vision, or trouble seeing objects clearly
• Nausea is an important symptom to observe because it means the nervous system is experiencing trouble.
• Language dysfunction means problem with understanding what is being said and experiencing issues with speaking as well.
• Dizziness and loss of balance in the body.
• Memory loss as the supply of blood affects the memory centers of the cerebellum.
• Weakness in the limbs as the brain loses coordination with the muscles.
• Sharp and severe headaches that come in episodes.
• Skin breakdown
• Depression and nervousness.
• Chronic pain in the body
• Some later symptoms and complications of posterior cerebral artery syndrome include urinary tract and pulmonary infections.
Diagnosis of Posterior Cerebral Artery Syndrome
Detection of Posterior Cerebral Artery Syndrome needs a complete neurological and physical exam. An extensive exam with a team of doctors and neurosurgeons reveals the extent of the damage caused to the posterior brain and the severity of the symptoms.
Numbness of the limbs is the most common physical signal and a visual-cut is the most common neurological sign that doctors look out for in patients who are either at a risk of a PC stroke or are suffering from of Posterior Cerebral Artery Syndrome. Once done, the diagnosis will reveal whether the person should be treated surgically or with medication.
In terms of surgery, neurosurgeons perform a procedure to clean up the posterior cerebral arteries by opening up the vessel that has an obstruction. This obstruction is pinpointed and then picked out in one piece. During this surgery, flow of blood is rerouted to make sure that the other parts of the brain are not deprived of fresh oxygen.
PC stroke is a medical emergency and should be looked after immediately. As soon as the flow of blood can be restored, the severity of signs and symptoms of Posterior Cerebral Artery Syndrome can be controlled. While the aftereffects of a PC stroke can only be improved, not treated, timely intervention may be able to minimize fatal damage.