Tag: Third Ventricle

  • Cranio Sacral Therapist and Student Newsletter 20

    January  18 – 2007

    Questions and comments for this issue:

    + Talking during treatment.
    + How the face reflects the cranial rhythm.
    + Why is the ventricular system so important?

    Hello,

    Let me just put my Hula Hoop down for a second
    so I can talk to you.  You don’t Hula?
    Why, it’s the latest re-fad.  You know, a fad
    that makes a comeback.

    In America, “hip hooping” classes, videos and
    Hoopster clothing lines are springing up across
    the country. Beyonce and Charlize Theron are huge
    fans.  They are always pestering me to join them
    at hip hooping class.

    I can see I’m wasting my time talking to you
    about this.  You just want to hear about cranio.

    Fair enough, let’s get on with the mailbag.

    ***QUESTION***

    Dear John,

    Thank you for your newsletters they are wonderful.

    Here is my question.
    I would like to get some of my patients more
    involved in their process when we are working
    together but I don’t want to do a full somato-
    emotional release type thing with them.
    Do you have any suggestions for an intermediary
    type approach I could do?

    Thanks again.
    PR.
    California.

    MY COMMENTS:

    Okey dokey.  Here’s something you can do.

    Once the person is on the table and you are
    settling in and chit chatting and generally
    entraining with them.

    No, not entertaining them, I said ENTRAINING
    with them. Now take that clown suit off and lets
    get back to the session.

    Tell the person that you are going to do
    something a bit different this week.  Keep your
    tone light.

    Take up a contact that allows you a good sense
    of the whole cranio sacral system.  Ask the person
    to close their eyes and begin to see themselves
    shrinking on the inside until they are small
    enough to walk around, inside the structures of
    their body.

    Whenever you are talking with a patient choose
    your words carefully.  I used the word ‘see’ on
    purpose.   ‘I want you to see yourself shrinking
    on the inside until you are small enough to be
    able to walk around inside the structure of your
    body.’

    Don’t say visualise or imagine as I have found
    these words can short circuit the process before
    it even gets started.

    Why?

    Well, because some people are convinced they
    have no imagination and others have tried
    visualisation before and are, ‘just no good at
    it.’

    Start off with a relatively restriction free
    area.  Ask the person to describe what it looks
    like.  Get them to describe the area in as much
    detail as possible.  Encourage them to tell you
    what they see, even though they may be inhibited
    by their lack of anatomical knowledge.

    They can shrink themselves to whatever size
    they need to be to pass between structures or see
    something in detail.  Ask them if everything looks
    okay in the area.  If it is, move on to another
    area, one where you sense a restriction, though
    you don’t need to tell them you think it is
    restricted.

    If they tell you that everything is NOT okay in
    an area, ask them to describe what it is that
    looks unnatural.  Encourage them to be as specific
    as possible.  You may need to move your hands
    closer to the area they are describing.

    Ask them what needs to happen for the area to
    return to a more natural state.

    Wait for their answer.

    If they are having difficulty seeing a way to
    correct the situation you can suggest solutions to
    them using the symbols they have communicated to
    you. Make full use of their size in the area.

    They can climb in between bones and push them
    apart.  They can pull and push things with their
    hands in very specific ways. You can suggest
    little tools that may help them, but avoid
    frightening tools like hammers and saws etc.

    You can suggest light beam machines to warm
    cold areas.  Ice guns for cold.  Muscle oil
    aerosol cans for tight or stiff muscles and so on.

    All the time you will be monitoring and
    following the changes they are making on the
    inside with your hands.

    This is generally an enjoyable technique for
    you and the person.  It seldom has a huge
    emotional aspect and is particularly good with
    patients who are very out of touch with their
    feelings.

    Most people don’t find it threatening and are
    amused by what they find in their bodies. They can
    be surprised at the clarity of the images they
    see. This is because the following of your hands
    enables the person to see more clearly the
    restriction in their bodies.

    This technique is a very useful way to involve
    the person and use their attention as an extension
    of yours, to check things out and correct them
    from the inside.

    As you get more experience with it you will get
    a sense of who this technique is appropriate for.
    It is a good introduction for other forms of
    therapeutic conversation which you may intend to
    use in future treatment sessions with the person.

    ***QUESTION***

    Dear John,
    I am currently studying the face and the way it
    moves with the cranial rhythm.  Frankly I find it
    confusing and hard to remember.

    I’m hopping you have some little analogy or trick
    for making it a bit clearer.

    Yours Sincerely.

    KS.
    Canada.

    MY COMMENTS:

    Before I get into the face I need to quickly
    run through flexion and extension in the cranium.

    Think of the cranium as a balloon.

    During extension the balloon narrows and
    elongates and during flexion it expands and
    becomes squat.  Long and thin in extension, short
    and squat in flexion.

    To understand the way the face moves with the
    cranial rhythm, take the balloon and add a small
    box.  Attach it to the balloon roughly where the
    face hangs off the cranium.

    Now, lets look at how the box moves with the
    balloon.

    In extension the balloon will become long and
    thin.  The box will arc inferiorly and narrow as
    the whole balloon elongates

    During flexion the balloon will become short
    and squat.  The box will arc superiorly and
    broaden as the balloon shortens and broadens.

    So what does this feel like in practice?

    Sit at the head of the person.  With their
    permission, place your hands on their face, thumbs
    on their forehead and fingers on their mandible.

    During flexion you will feel your thumbs and
    fingers move closer together while in extension
    they will move further apart.

    Once you get this overall movement you can work
    out the specifics of each bone relatively easily.

    Here are some other things to consider.  The
    mandible and the frontal bone moving towards each
    other in flexion could put stress on the bones of
    the face but this compressive movement is
    naturally absorbed by the orbits.

    This makes the orbits particularly vulnerable
    to any restriction patterns present in the face or
    cranium, especially the posterior aspect of the
    orbit.

    Certain bones of the face are designed to
    reduce the amplitude of the movement of some of
    the larger bones they articulate with. These bones
    are the palatines, the zygomae, the vomer and the
    ethmoid.

    You can think of them like ‘washers’ between
    two larger bones.  William Sutherland called these
    bones the ‘speed reducers’ but they do not
    actually reduce the frequency of the rhythm, they
    reduce the amount of movement or amplitude.  So a
    40 micron movement of the frontal can be reduced
    to a 10 micron movement in the Zygomae. [Remember
    a sheet of writing paper is 100 microns thick.]

    ***QUESTION***

    Hi John,
    I am being repeatedly told that the ventricles are
    very important but I am not sure why.  I have
    asked this question of my tutors repeatedly but
    never got a satisfactory answer.

    I would be grateful to hear your explanation.
    Thanking you in anticipation.
    PB
    South Africa

    MY COMMENTS:

    It may be easier for you to think of the whole
    system in terms of plumbing, which it is in a way.
    It’s a very important and significant plumbing
    system.

    The ventricular system, is a collection of
    cavities and canals deep within the brain and
    spinal cord. It consists of 4 ventricles connected
    by various channels.  It always looks to me like a
    model of a space ship.  Think Star Trek.

    The four ventricles are made up of the 2
    lateral Ventricles located within the two cerebral
    hemispheres, each of which connect via an inter-
    ventricular foramen to the 3rd ventricle which is
    located between the two thalami of the brain.

    The 3rd ventricle connects inferiorly through
    the cerebral aqueduct (or aqueduct of Sylvius as
    you will see it in some books) to the 4th
    ventricle which is located between the cerebellum,
    posteriorly and the pons and medulla, anteriorly.

    The 4th ventricle continues inferiorly as the
    central canal passing down the centre of the
    spinal cord.

    The whole ventricular System is filled with
    Cerebrospinal Fluid.

    So that’s the plumbing.  Now let’s look at
    inlet and outlet valves.

    The INLET valves are located in the roof of
    each of the four ventricles and are called Choroid
    Plexi.  These are filter like structures through
    which cerebrospinal fluid is formed as a filtrate
    from arterial blood.  Arterial blood enters the
    choroid plexi from the cerebral arteries; then
    blood cells, proteins and other large particles
    are filtered out.  The pure colourless fluid that
    filters through this choroid plexi into the
    ventricular system is cerebrospinal fluid.

    I will get to the outlet valves in a minute.
    First I want to focus on something that is very
    easy to get confused about.
    We know that the membrane system contains
    cerebrospinal fluid, right?

    Just nod.

    And now we have a good idea of how
    cerebrospinal fluid enters the ventricular system.
    And we also know the ventricular system is
    contained within the membrane system.  The thing
    is the ventricular system is, for the most part,
    closed.
    So how does cerebrospinal fluid get out of the
    ventricular system into the membrane system?

    Very good question.  It all happens in the 4th
    ventricle.  In the posterior and lateral walls of
    the 4th ventricle there are three foramina,  – the
    foramen of Magendie which is in the middle
    posteriorly and the 2 foramina of Luschka,
    bilaterally.

    It is through these 3 foramina that
    cerebrospinal fluid passes out into the sub-
    arachnoid space where it circulates around the
    brain and spinal Cord.

    Now back to the OUTLET valves.
    Cerebrospinal fluid is eventually returned to
    the blood via the Arachnoid Villi which protrude
    from the sub-arachnoid space through to the
    superior sagittal sinus of the Brain.  It re-joins
    the venous blood which then drains from the venous
    sinuses via the internal jugular Vein to be
    returned to the heart.

    So that’s the plumbing, the general flow and
    the inlet and outlet valves.   The significance is
    that this system is in continuous use which means
    it has to be in working order all the time.  If
    any one of the valves or canals of foramina are
    not working properly the effects are serious.

    Just think of the person having a spinal tap.
    Only a tiny amount of cerebrospinal fluid is
    removed yet the person will have to lie horizontal
    for 24 hours to avoid severe headaches.

    Also if there is a problem in this system it’s
    not like you can just shut it down while repairs
    are made.

    So that’s it for this issue.

    Cheerio for now.

    Till the next time.

    Your Mate,

    John D.

  • B1.26.0 – The Ventricular System

    << Back to Basics 1 syllabus

    *As with all anatomy I suggest you search for each new term on google then click on the ‘Images’ tab at the top of the page.  Look at as many different pictures of each structure, from as many different angles as you can. Then look at it on the Visible Body. This will help you get a 3 dimensional image of the structure in your head.

    The Ventricular System is a system of cavities and canals deep within the brain and spinal cord. They have a thin membranous lining called the Ependyma.  The whole Ventricular System is filled with Cerebrospinal Fluid. The Ventricular System consists of four ventricles connected by various communicating channels.

    These are:

    ❍ Two lateral Ventricles (1st and 2nd Ventricles) located within the two cerebral hemispheres, each of which communicates via an inter-ventricular foramen to

    ❍ The third Ventricle located between the two Thalami of the brain.
    The Third ventricle communicates inferiorly through the cerebral aqueduct (aqueduct of sylvius) to

    ❍ The fourth Ventricle located between the Cerebellum (posteriorly) and the Pons and Medulla (anteriorly).  The fourth Ventricle is continuous inferiorly with the central canal passing down the centre of the Spinal Cord.

    In the roof of each of the four ventricles are located Choroid Plexi.
    These are filter like structures through which Cerebrospinal Fluid is formed as a filtrate from arterial blood.  Arterial blood enters the Choroid Plexi from the cerebral arteries; then blood cells, proteins and other large particles are filtered out (remaining in the blood).  The pure colourless fluid that filters through this Choroid Plexi into the Ventricular System is Cerebrospinal Fluid.

    HOW DOES CEREBROSPINAL FLUID GET OUT OF THE VENTRICULAR SYSTEM?

    In the posterior and lateral walls of the fourth ventricle are three foramina –

    The Foramen of Magendie (medial aperture), posteriorly, and
    Two Foramina of Luschka (lateral apertures), bilaterally.

    Cerebrospinal Fluid flows throughout the Ventricular System. It passes out through the Foramina of Magendie and Luschka into the sub-arachnoid space where it circulates throughout the Sub-arachnoid space around the Brain and Spinal Cord.

    Cerebrospinal Fluid also seeps through the walls of the ventricles into the nerve tissue of the Brain and Spinal Cord.  From the sub-arachnoid space it seeps through the Pia Mater into the tissues of the Brain and Spinal Cord. Cerebrospinal Fluid also seeps out with the peripheral nerves of the spinal cord as they leave the Central Nervous System and travel out to the periphery.

    REABSORBTION
    Cerebrospinal Fluid is eventually returned to the blood via the Arachnoid Villi which protrude from the sub-arachnoid space through to the Superior Sagittal Sinus of the Brain. It re-joins the Venous blood which then drains from the Venous Sinuses via the Internal Jugular Vein to be returned to the heart.

    So the direction of flow is,

    • Arterial blood is pumped into the Choroid Plexi in the roofs of the Ventricles where it is filtered into cerebrospinal fluid.
    • The lateral ventricles drain into the Third Ventricle via Inter-ventricular foramina.
    • The third ventricle drains into the Aqueduct of Sylvius to the Forth Ventricle.
    • It is in the Fourth Ventricle that the cerebrospinal fluid leaves the ventricles and enters the sub arachnoid space via the foramina of Luschka and Magendie. (It also travels down the central canal of the spinal cord.)
    • It travels throughout the sub arachnoid space.
    • Some of it seeps out with the peripheral nerves and is reabsorbed as an extracellular fluid.
    • The bulk of it is reabsorbed by the arachnoid granulations of the arachnoid villi. These transform it into Venous blood as they deposit it into the Venous sinuses, particularly the superior sagittal sinus.

    << Back to Basics 1 syllabus