Study Notes Review of knowledge points of middle cerebral artery anatomy

Knowledge points of middle cerebral artery anatomy

In the process of learning middle cerebral artery anatomy, there are many constant concepts and information, and there are many variations, find the appropriate way, according to the following key words as the main line, you can achieve the purpose of fully mastering MCA anatomy:

Origin, course, bifurcation, segemnt

There are two keys to learning MCA segmented anatomy: (1) several key points in the segment and the starting and ending points of each segment; (2) The anatomical division of the lateral fissure and its relationship
to the segments of MCA.

ICA has a fork, bifurcation of internal carotid artery, and MCA has a fork, bifurcation of middle cerebral artery
.

Before understanding the early branching concept, you need to know that M1 is actually two parts
: pre-fork and post-fork.

The closer the beginning of the early branch is to the ICA bifurcation, the thicker the diameter and the more likely it is to develop cortical branches and leguinated arteries
.

Below we will review the sections and start and end points of MCA from near and far:

1.
Starting point (origin):

(1) Terminal bifurcation of ICA = bifurcation of internal carotid artery
.

（2）location：

2, M1 segment = sphenoidal segment = horizontal segment:

(1) Start and end point: ICA terminal bifurcation → walking flat in the lateral fissure butterfly → MCA knee
.

(2) course: Inside the lateral fissure butterfly, walk horizontally from the inside out
.

（3）location：

(4) About 90% of hemisphere MCA forks occur proximal to the MCA knee, so M1 is divided into two parts:

(5) Early branches:

3, MCA knee (genu of middle cerebral artery)

The M1 segment (horizontal segment) of the middle cerebral artery runs outward horizontally, and when it reaches the insular threshold level, the middle cerebral artery is bent at 90° and turned upwards, continuing to the M2 segment (insular segment), and this 90° curved part of MCA is called the MCA knee
.
The MCA knee is the boundary
between the M1 and M2 segments.

4, M2 segment = insular segment

(1) Start and end point: genu of the MCA (genu of the MCA) → circularsulcus of the insula.

(2) course: Walk on the surface of the insula and send out some branches to supply the insula
.

(3) Composition: M2 is composed of upper stem and lower stem, and the upper stem and lower stem are of different
sizes.

(4) Branch:

5) Circular sulcus of the Insula:

The insula is surrounded and separated from the lid by a deep trench called the circular sulcus of the insula or limiting sulcus of the insula or priinsular sulcus, which is divided into upper, anterior and lower parts
.

The M2 and M3 sections of MCA are bounded
by the island ring ditch.

6, M3 segment = opercular segment

(1) Start and end point: from the circular sulcus of the insula → end at the surface of the sylvian fissure
.

(2) course: The branches that make up the M3 segment run close to the lateral fissures of the forehead, parietal and temporal
covers.

7, M4 segment = cortical branches

(1) Starting point: from the surface
of the lateral crack.

(2) course: Walks on the cortical surface
of the cerebral hemisphere.

(3) MCA cortical branch mainly supplies 12 areas:

II.
Branch

1.
Types of MCA forks:

The pipe diameter of each trunk is related
to the size of the distribution area.

2.
Central and cortical branches of MCA:

3.
MCA fork and branch type:

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