Understanding the Circle of Willis: Anatomy and Variations with Clinical Implications | Chapter 9 | Medical Science: Updates and Prospects Vol. 4

 

The human brain is the main controlling organ of the body. So, the normal and varied anatomy of the brain, including its vascular supply, is very important for neurosurgeons for the management of neurovascular diseases of the brain. Now, the brain is supplied by mainly irrigated by the internal carotid artery and basilar-vertebral arteries and branches of these arteries form an arterial polygon known as the circle of Willis at the base of the brain. Standard configuration of the circles of Willis is present in only one-third of the population only emphasising that quite a large population suffers from variation in the formation of the circle of Willis. The main variations of the circle of Willis include asymmetry, fenestration, duplication, aplasia, agenesis, curved, kinked and tortuous course of the arteries forming the circle of Willis. These variations may lead to aneurysm, stroke and may cause ischemia of parts of the brain supplied by arteries forming the circle of Willis. These clinical conditions may be fatal. So, to manage these clinical conditions of the brain, thorough knowledge of the normal and varied anatomy of the circle of Willis is very important for neurosurgeons. The aim of this chapter is to expound the normal anatomy along with the variations associated with the arteries forming the circle of Willis so that vascular diseases of the brain can be managed successfully with minimum complications.

 

Author(s) Details

Rajani Singh
Department of Anatomy, Graphic Era Institute of Medical sciences, Dhulkot, Uttrakhand, India.

 

Please see the book here :- https://doi.org/10.9734/bpi/msup/v4/6921

 

Frontal Lobe of the Brain: The Neglected Supremacy | Chapter 3 | Achievements and Challenges of Medicine and Medical Science Vol. 13

The frontal lobe represents part of the cerebral cortex that lies anterior to the central sulcus and is limited laterally and inferiorly by the lateral sulcus. The term prefrontal cortex (PFC) describes anatomically the association cortex anterior to the Brodmann area (6) and (4). The frontal lobe and prefrontal cortex are the parts of the brain that distinguish human beings from other creatures and this is because of its complex anatomy and the amazing many roles in the higher functions. Till recently, the frontal lobe was considered the most lobe containing non-eloquent areas and so-called (silent areas) and this is because of the poor knowledge about the anatomy and neuroscience of this spectacular lobe. The prefrontal region is responsible for the Cognitive and behavioral frontal lobe functions more than the frontal lobes in general. The prefrontal cortex anterior to the frontal eye field (Brodmann area 8) is not involved in any concrete task. It does not smell, feel, see, or move part of the body, but this area allows the superiority of humans over the other primates. Neurosurgeons deal a lot with this lobe during brain surgeries but because of poor information about deep microanatomy and neuroscience, they usually consider it as a safe area to do big surgery with aggression sometimes without big evident side effects or complications. This is in comparison to surgery conducted in eloquent areas which is usually done with more caution and consumption of all imaging and technical modalities to minimize the risk of injury. Such a concept about the surgery in the frontal lobe can be considered as disrespect from micro anatomical point of view and neuroscience aspect. This is a brief narrative review about the deep anatomy of the frontal lobe with a literature review aiming to raise awareness about the big importance of the frontal lobe and especially the prefrontal cortex for the human being in the higher functions, cognition and personality and to change the old concept that used to rank the frontal lobe as silent area and to show that frontal lobe has got the supremacy. The study concludes that other brain regions receive disproportionate attention compared to the frontal lobe, particularly from a surgical perspective. Recognizing the significance of the frontal lobe is important in both surgical and research approaches.

 

Author (s) Details

 

Fawaz Eljili
Bahri Teaching Hospital, Sudan.

 

Ahmed Zidan
Neurosurgery Department, AL Tamyouz (Haj Almardi) Trauma Center, Sudan.

 

Honida Ali
Neurospine Center, Ribat University Hospital, Sudan.

 

Mohammed Mustafa
National Center for Neurological Sciences (NCNS), Sudan.

 

Please see the book here:- https://doi.org/10.9734/bpi/acmms/v13/4388