Math Is Fun Forum

Heart Valve Surgery

Gist

How is heart valve surgery done?

The surgeon makes a long cut down the centre of your chest, through your breastbone. Your heart is connected to a machine to keep blood flowing around your body during the operation (heart-lung bypass machine). The surgeon cuts into your heart to reach the damaged valve.

Can you walk after heart valve surgery?

People are usually practicing very basic self-care and are encouraged to get up, to breathe deeply and to resume eating, drinking and walking as soon as possible after surgery.

Summary:

What is heart valve surgery?

Heart valve surgery and procedures are performed to repair or replace a valve in the heart that is not working properly because of valvular heart disease (also called heart valve disease). Heart valve surgery is open-heart surgery through the breastbone, into the chest. It is a major operation that can last two hours or longer and recovery often takes several weeks. There are newer, less invasive procedures suitable for some types of valvular heart disease, but they are only done at certain hospitals.

Why is it done?

In a healthy heart, valves control the flow of blood by making it move in one direction through the heart and the body. If a valve is not working correctly, blood flow and the delicate network of blood vessels that carry oxygen throughout the body are affected.

If your valve problem is minor, your doctor may monitor your symptoms or treat you with medication. If your condition is more serious, surgery is usually required to repair or replace the valve to prevent any lasting damage to your heart valve and your heart.

Heart valve surgery and procedures are performed to repair or replace a valve in the heart that is not working properly because of valvular heart disease (also called heart valve disease). Heart valve replacement surgery is open-heart surgery through the breastbone, into the chest. It is a major operation that can last two hours or longer and recovery often takes several weeks. There are newer, less invasive procedures suitable for some types of valvular heart diseases.

In a healthy heart, valves control the flow of blood by making it move in one direction through the heart and the body. The valve can either become stenotic, which means it is narrowed and thus does not allow the blood to flow smoothly from one chamber to another or it starts leaking which hampers the forward flow of blood.

If your valve problem is minor, your doctor may monitor your symptoms or treat you with medication. If your condition is more serious, surgery is usually required to repair or replace the valve to prevent any lasting damage to your heart valve and your heart.

What is Done?

Depending on the problem, there are several different procedures for repairing or replacing valves.

1. Surgical Valve Repair

Surgical procedures are generally used for problems with the mitral or tricuspid valves.

2. Commissurotomy

It is a treatment for a tight valve. The valve flaps (leaflets) are cut to loosen the valve slightly, allowing blood to pass easily.

3. Annuloplasty

It is done for a leaky valve. There is a ring of fibrous tissue at the base of the heart valve called the annulus. To repair an enlarged annulus, sutures are sewn around the ring to make the opening smaller. Or, a ring-like device is attached around the outside of the valve opening to support the valve so it can close more tightly.

4. Valvulotomy

It is a procedure to enlarge narrowed heart valves. It can also be done with the help of a balloon.

5. Non-Surgical Valve Repair

Percutaneous or catheter-based procedures are done without any incisions in the chest or stopping the heart. Instead, a thin flexible tube called a catheter is inserted into a blood vessel in your groin or arm and then threaded through the blood vessels into your heart. Percutaneous or balloon valvuloplasty/valvotomy is used for stiffened or narrowed (stenosed) pulmonary, mitral, or aortic valves. A balloon tip on the end of the catheter is positioned in the narrowed valve and inflated to enlarge the opening. Percutaneous mitral valve repair methods – such as edge-to-edge repair – can fix a leaky mitral valve in a patient who is considered at high risk for surgery. A catheter holding a clip is inserted into the groin and up into the left side of the heart. The open clip is positioned beyond the leaky valve and then pulled back so it catches the flaps (leaflets) of the mitral valve. Once closed, the clip holds the leaflets together and stops the valve from leaking.

Details

Heart valve surgery repairs or replaces a valve that’s too narrow or doesn’t close right. Valves need to work efficiently to help blood flow the right direction through your heart. Heart valve surgery options include open, minimally invasive or through vein access to your heart. It takes one or two months to recover, depending on the surgery.

Overview:

What is heart valve surgery?

Heart valve surgery is an operation that fixes or replaces one or more of the four valves in your heart. Your valves, located between your heart’s four chambers, keep your blood moving the right way. Valves act like doors that open and close with each heartbeat, letting blood flow in and out of the chambers. When valves are working right, your blood should flow through your heart in one direction each time your heart beats.

Your four heart valves are:

* Tricuspid, between your right upper and lower chambers.
* Pulmonary, between your right ventricle (lower chamber) and your pulmonary artery.
* Mitral, between your left upper and lower chambers.
* Aortic, between your left ventricle (lower chamber) and your aorta.

Some of the blood may go back to the chamber or room it just left. Other times, a valve may become narrow, which may prevent blood from moving forward. This is a problem because it keeps your heart from working efficiently. Although heart valve surgery may make you feel fearful, it helps your heart work better. And if your heart’s working better, you’ll feel better, too.

Types of heart valve surgery

The type of heart valve surgery you have will depend on several factors. Your provider will consider:

* Your heart’s structure.
* Your age.
* Other medical conditions you may have.
* Your lifestyle.

Tests will tell your healthcare provider the location, type and extent of your valve disease. Your heart valve issue may have started at birth, or you may have developed a leak, stiffness or narrowing in your valve. The test results help determine the best type of procedure for you.

Your cardiac surgeon can combine valve surgery with other heart surgeries. Examples include surgeries that involve more than one valve procedure and combining heart valve surgery with:

* Bypass surgery.
* Aortic aneurysm surgery.
* Surgery to treat atrial fibrillation.

Heart valve repair surgery

A repair surgery fixes the damaged or faulty valve while preserving much of your own tissue. Surgeons repair mitral valves more than the other valves, but repair surgery can also treat problems with the aortic and tricuspid valves.

Heart valve replacement surgery

Heart valve replacement surgery removes the faulty valve and replaces it with a biological (pig, cow or human tissue) or mechanical (metal or carbon) valve. All valve replacements are biocompatible. That means your immune system won’t reject your new valve. Replacement options include the Ross procedure and minimally invasive procedures like TAVR.

Can a heart valve repair itself?

No, a heart valve can’t repair itself. Valve disease doesn’t go away. It gets worse with time. As the disease gets worse, you’ll have more symptoms and your overall health will suffer. These changes often happen slowly, but they can also occur very quickly.

Depending on the type and extent of valve disease you have, medication may help with symptoms for the short term. Surgery is the only effective long-term solution. Your healthcare provider will help determine when it’s time for surgery.

When is heart valve surgery necessary?

You’ll most likely need heart valve surgery if medicine doesn’t help anymore for symptoms like:

* Chest pain.
* Difficulty breathing.
* Fainting.

Treatment Details:

How should I prepare for heart valve surgery?

You may have tests the day before your surgery. These may include:

* Chest X-ray.
* Echocardiogram.
* Electrocardiogram (EKG).
* CT (computed tomography) scan.
* Cardiac catheterization.
* Blood tests.

Check with your healthcare provider about which medications you can take before surgery. Don’t eat or drink anything after midnight the day of your surgery.

On the day of your procedure, wear loose, comfortable clothes and shoes that are easy to put on. If you wear a bra, you may want to bring one that’s easy to put on without raising your arms. The person who brings you to the hospital can hold on to these items for you during surgery.

Before your surgery, a healthcare provider will shave and clean the area where your surgeon will be working.

What happens during valve surgery on your heart?

During heart valve surgery, a provider will:

* Give you medicine through an IV in your arm or hand so you can sleep deeply and painlessly.
* Use the smallest incision they can for your surgery.
* Set up a machine to take over for your heart and lungs during surgery.
* Repair or replace your heart valve.
* Restart your heart.
* Close your chest.

Heart valve surgery options include:

* Traditional or open-heart surgery: An incision (6 to 8 inches) through your breastbone.
* Minimally invasive heart valve surgery: A smaller incision (3 to 4 inches or smaller). Techniques include endoscopic or keyhole approaches (also called port access, thoracoscopic or video-assisted surgery) and robotic-assisted surgery.
* Transcatheter: Your provider will put a catheter into a larger artery, like your femoral artery in your groin, and do the work without cutting your chest.

How long does this procedure take?

Open-heart surgery for a heart valve replacement can take two to five hours. Repairs or minimally invasive procedures may take less time.

What happens after heart valve surgery?

After surgery, your healthcare team may move you to an intensive care unit (ICU) where they can monitor you closely. After that, you’ll be in a regular room. You may be in the hospital for five to seven days.

Machines connected to you will monitor your blood pressure and heart rate. You may have tubes coming out of your chest to drain fluids.

Your provider will encourage you to eat, drink and walk as soon as you can after surgery. You can start with short walks around your room or down the hall and increase your distance little by little.

Your provider may sign you up for cardiac rehab, a carefully monitored exercise program.

Risks / Benefits:

What are the benefits of heart valve surgery?

Heart valve surgery can ease your symptoms, improve your life expectancy and help prevent death.

The potential advantages of heart valve repair vs. heart valve replacement surgery are:

* Lower risk of infection.
* Less need for lifelong anticoagulant (blood thinning) medication.
* Valve surgeries, including heart valve repair and replacement, are the most common minimally invasive procedure.

The benefits of minimally invasive surgery include:

* Lower chance of infection.
* Less bleeding and trauma.
* Shorter hospital stay.
* Shorter recovery.
* Improved cosmesis (appearance) and smaller wounds.

What are the risks or complications of heart valve surgery?

Any surgery involves risks. Heart valve surgery risks may include:

* Heart attack.
* Heart failure.
* Abnormal heart rhythm — you may need a pacemaker.
* Stroke.
* Blood clots.
* Infection.
* Bleeding.

Risks are related to your age, other medical conditions you may have and how many procedures you have in a single operation. Your cardiologist and surgeon will talk to you about these risks before your surgery.

If you’ve had a valve fixed or replaced, you may be at a higher risk of getting infective endocarditis. But this can also happen with an unrepaired faulty valve. In certain cases, your healthcare provider may prescribe antibiotics to keep you from getting endocarditis from some types of dental work. You can reduce the risk of endocarditis yourself by taking good care of your teeth.

Recovery and Outlook:

How long is recovery after heart valve surgery?

Heart valve surgery recovery takes about four to eight weeks. But your recovery time may be shorter if you had minimally invasive surgery or surgery through a vein.

The way you feel after surgery depends on:

* Which valve was repaired or replaced.
* Your overall health before the surgery.
* Which method your provider used to get to your heart (large incision, small incision or through a vein).
* How the surgery went.
* How well you take care of yourself after surgery.

Caring for yourself after surgery

Recovery after heart valve surgery takes time. Be kind to yourself. Here are some tips:

* Go to your follow-up appointments during recovery so your provider can monitor your progress.
* Don’t take on more than you can handle. You can expect to tire easily for the first three weeks after surgery.
* Don’t drive for a few weeks after surgery.
* Don’t handle anything that weighs more than 15 pounds for the first six to eight weeks after surgery.
* Talk to your provider about when you can go back to work. It’s usually six to 12 weeks after surgery.

What is the survival rate following heart valve surgery?

A study found that people who were more physically active in the year after surgery had a lower risk of death than those who didn’t exercise much. The death rate ranges from 0.1% to 10% depending on the operation and a person's overall health.

When To Call the Doctor:

When should I call my healthcare provider?

Contact your provider if:

* You have chest pain or pain near your incision.
* You feel depressed. This can happen after surgery and can make your recovery take longer.
* You have a fever, which can be a sign of infection.
* You gain more than 5 pounds, which may mean you’re retaining fluid.

Additional Information:

Overview

Heart valve surgery is a procedure to treat heart valve disease. Heart valve disease happens when at least one of the four heart valves is not working properly. Heart valves keep blood flowing in the correct direction through the heart.

The four heart valves are the mitral valve, the tricuspid valve, the pulmonary valve and the aortic valve. Each valve has flaps — called leaflets for the mitral and tricuspid valves and cusps for the aortic and pulmonary valves. These flaps should open and close once during each heartbeat. Valves that don't open and close properly change blood flow through the heart to the body.

In heart valve surgery, a surgeon repairs or replaces the damaged or diseased heart valve or valves. Methods to do this may include open-heart surgery or minimally invasive heart surgery.

The type of heart valve surgery needed depends on age, overall health, and the type and severity of heart valve disease.

Types

* Annuloplasty
* Valvuloplasty

Why it's done

Heart valve surgery is done to treat heart valve disease. There are two basic types of heart valve disease:

* A narrowing of a valve, called stenosis.
* A leak in a valve that allows blood to flow backward, called regurgitation.

You might need heart valve surgery if you have heart valve disease that affects your heart's ability to pump blood.

If you don't have symptoms or if your condition is mild, your healthcare team might suggest regular health checkups. Lifestyle changes and medicines might help manage symptoms.

Sometimes, heart valve surgery may be done even if you don't have symptoms. For example, if you need heart surgery for another condition, surgeons might repair or replace a heart valve at the same time.

Ask your healthcare team whether heart valve surgery is right for you. Ask if minimally invasive heart surgery is an option. It does less damage to the body than does open-heart surgery. If you need heart valve surgery, choose a medical center that has done many heart valve surgeries that include both repair and replacement of the valve.

Risks

Heart valve surgery risks include:

* Bleeding.
* Infection.
* Irregular heart rhythm, called arrhythmia.
* Problem with a replacement valve.
* Heart attack.
* Stroke.
* Death.

How you prepare

Your surgeon and treatment team discuss your heart valve surgery with you and answer any questions. Before you go to the hospital for heart valve surgery, talk with your family or loved ones about your hospital stay. Also discuss what help you'll need when you come home.

Food and medicines

Before you have heart valve surgery, talk to your care team about:

* Any medicines you regularly take and whether you can take them before your surgery.
* Allergies or reactions you've had to medicines.
* When you should stop eating or drinking the night before or the morning of the surgery.

Clothing and personal items

If you're having heart valve surgery, your treatment team might suggest that you bring certain items to the hospital, including:

* A list of your medicines.
* Eyeglasses, hearing aids or dentures.
* Personal care items, such as a brush, a comb, a shaving kit and a toothbrush.
* Loose, comfortable clothing.
* A copy of your advance directive. This is a legal document. It includes instructions about the kinds of treatments you want — or don't want — in case you become unable to express your wishes.
* Items that help you relax, such as portable music players or books.

During heart valve surgery, do not wear:

* Contact lenses.
* Dentures.
* Eyeglasses.
* Jewelry.
* Nail polish.

Gemstones

Gist

The 12 gemstones, known as birthstones, correspond to each month of the year, with modern lists often including alternatives for some months, featuring Garnet (Jan), Amethyst (Feb), Aquamarine (Mar), Diamond (Apr), Emerald (May), Pearl/Alexandrite (Jun), Ruby (Jul), Peridot (Aug), Sapphire (Sep), Opal/Tourmaline (Oct), Topaz/Citrine (Nov), and Tanzanite/Zircon/Turquoise (Dec), representing different virtues and qualities.

While diamonds are known as the "king of all gems" for their hardness and brilliance, the Ruby is most often called the "King of Gemstones" (or Ratnaraj in Sanskrit) due to its deep red color, rarity, association with royalty, power, and vitality, and highest per-carat price among colored stones. Both hold prestigious titles, but the ruby's fiery red hue and historical significance often earn it the "king" crown. 

Goshenite is a colorless gem variety of beryl. It is sometimes called the “mother of all gemstones”because it can be transformed into other gems, such as emerald, morganite, or bixbite. Goshenite is also referred to as the purest form of beryl since there are generally no other elements present in the stone.

Summary

A gemstone is any of various minerals highly prized for beauty, durability, and rarity. A few noncrystalline materials of organic origin (e.g., pearl, red coral, and amber) also are classified as gemstones.

Gemstones have attracted humankind since ancient times, and have long been used for jewelry. The prime requisite for a gem is that it must be beautiful. The beauty may lie in colour or lack of colour; in the latter case, extreme limpidity and “fire” may provide the attraction. Iridescence, opalescence, asterism (the exhibition of a star-shaped figure in reflected light), chatoyance (the exhibition of a changeable lustre and a narrow, undulating band of white light), pattern, and lustre are other features that may make a gemstone beautiful. A gem must also be durable, if the stone is to retain the polish applied to it and withstand the wear and tear of constant handling.

In addition to their use as jewelry, gems were regarded by many civilizations as miraculous and endowed with mysterious powers. Different stones were endowed with different and sometimes overlapping attributes; the diamond, for instance, was thought to give its wearer strength in battle and to protect him against ghosts and magic. Vestiges of such beliefs persist in the modern practice of wearing a birthstone.

Of the more than 2,000 identified natural minerals, fewer than 100 are used as gemstones and only 16 have achieved importance. These are beryl, chrysoberyl, corundum, diamond, feldspar, garnet, jade, lazurite, olivine, opal, quartz, spinel, topaz, tourmaline, turquoise, and zircon. Some of these minerals provide more than one type of gem; beryl, for example, provides emeralds and aquamarines, while corundum provides rubies and sapphires. In virtually all cases, the minerals have to be cut and polished for use in jewelry.

Except for diamond, which presents special problems because of its very great hardness (see diamond cutting), gemstones are cut and polished in any of three ways. Agate, opal, jasper, onyx, chalcedony (all with a Mohs hardness of 7 or less) may be tumbled; that is, they may be placed in a cylinder with abrasive grit and water and the cylinder rotated about its long axis. The stones become polished but are irregular in shape. Second, the same kinds of gemstones may instead be cut en cabochon (i.e., with a rounded upper surface and a flat underside) and polished on water- or motor-driven sandstone wheels. Third, gemstones with Mohs hardness of more than 7 may be cut with a carborundum saw and then mounted in a holder (dop) and pressed against a lathe that can be made to revolve with extreme rapidity. The lathe carries a point or small disk of soft iron, which can vary in diameter from that of a pinhead to a quarter of an inch. The face of the disk is charged with carborundum grit, diamond dust, or other abrasives, along with oil. Another tool used to grind facets is the dental engine, which has greater flexibility and sensitiveness than the lathe. The facets are ground onto the stone using these tools and then are polished as described above.

Of decisive significance for the modern treatment of gemstones was the kind of cutting known as faceting, which produces brilliance by the refraction and reflection of light. Until the late Middle Ages, gems of all kinds were simply cut either en cabochon or, especially for purposes of incrustation, into flat platelets.

The first attempts at cutting and faceting were aimed at improving the appearance of stones by covering natural flaws. Proper cutting depends on a detailed knowledge of the crystal structure of a stone, however. Moreover, it was only in the 15th century that the abrasive property of diamond was discovered and used (nothing else will cut diamond). After this discovery, the art of cutting and polishing diamonds and other gems was developed, probably in France and the Netherlands first. The rose cut was developed in the 17th century, and the brilliant cut, now the general favourite for diamonds, is said to have been used for the first time about 1700.

In modern gem cutting, the cabochon method continues to be used for opaque, translucent, and some transparent stones, such as opal, carbuncle, and so on; but for most transparent gems (especially diamonds, sapphires, rubies, and emeralds), faceted cutting is almost always employed. In this method, numerous facets, geometrically disposed to bring out the beauty of light and colour to the best advantage, are cut. This is done at the sacrifice of material, often to the extent of half the stone or more, but the value of the gem is greatly increased. The four most common faceted forms are the brilliant cut, the step cut, the drop cut, and the rose cut.

In addition to unfaceted stones being cabochon cut, some are engraved. High-speed, diamond-tipped cutting tools are used. The stone is hand-held against the tool, with the shape, symmetry, size, and depth of cut being determined by eye. Gemstones can also be made by cementing several smaller stones together to create one large jewel.

In some cases, the colour of gemstones is also enhanced. This is accomplished by any of three methods: heating under controlled conditions, exposure to X rays or radium, or the application of pigment or coloured foil to the pavilion (base) facets.

In recent times various kinds of synthetic gems, including rubies, sapphires, and emeralds, have been produced. Two methods of fabrication are currently employed, one involving crystal growth from solution and the other crystal growth from melts.

Details

A gemstone (also called a fine gem, jewel, precious stone, semiprecious stone, or simply gem) is a piece of mineral crystal which, when cut or polished, is used to make jewelry or other adornments. Certain rocks (such as lapis lazuli, opal, and obsidian) and occasionally organic materials that are not minerals (such as amber, jet, and pearl) may also be used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some softer minerals such as brazilianite may be used in jewelry because of their color or luster or other physical properties that have aesthetic value. However, generally speaking, soft minerals are not typically used as gemstones by virtue of their brittleness and lack of durability.

Found all over the world, the industry of coloured gemstones (i.e. anything other than diamonds) is currently estimated at US$1.55 billion as of 2023 and is projected to steadily increase to a value of $4.46 billion by 2033.

A gem expert is a gemologist, a gem maker is called a lapidarist or gemcutter; a diamond cutter is called a diamantaire.

Characteristics and classification

A collection of gemstone pebbles made by tumbling the rough stones, except the ruby and tourmaline, with abrasive grit inside a rotating barrel. The largest pebble here is 40 mm (1.6 in) long.
The traditional classification in the West, which goes back to the ancient Greeks, begins with a distinction between precious and semi-precious; similar distinctions are made in other cultures. In modern use, the precious stones are emerald, ruby, sapphire and diamond, with all other gemstones being semi-precious. This distinction reflects the rarity of the respective stones in ancient times, as well as their quality: all are translucent, with fine color in their purest forms (except for the colorless diamond), and very hard with a hardness score of 8 to 10 on the Mohs scale. Other stones are classified by their color, translucency, and hardness. The traditional distinction does not necessarily reflect modern values; for example, while most garnets are relatively inexpensive, a green garnet called tsavorite can be far more valuable than a mid-quality emerald. Another traditional term for semi-precious gemstones used in art history and archaeology is hardstone. The use of the terms "precious" and "semi-precious" in a commercial context is arguably misleading, as it suggests that certain stones are more valuable than others, which is not always reflected in their actual market value—although the terms may generally be accurate when referring to desirability.

In modern times gemstones are identified by gemologists, who describe gems and their characteristics using technical terminology specific to the field of gemology. The first characteristic a gemologist uses to identify a gemstone is its chemical composition. For example, diamonds are made of carbon (C), while sapphires and rubies are made of aluminium oxide (Al2O3). Many gems are crystals which are classified by their crystal system such as cubic or trigonal or monoclinic. Another term used is habit, the form the gem is usually found in. For example, diamonds, which have a cubic crystal system, are often found as octahedrons.

Gemstones are classified into different groups, species, and varieties. For example, ruby is the red variety of the species corundum, while any other color of corundum is considered sapphire. Other examples of beryl varieties include emerald (green), aquamarine (blue), red beryl (red), goshenite (colorless), heliodor (yellow), and morganite (pink).

Gems are characterized in terms of their color (hue, tone and saturation), optical phenomena, luster, refractive index, birefringence, dispersion, specific gravity, hardness, cleavage, and fracture. They may exhibit pleochroism or double refraction. They may have luminescence and a distinctive absorption spectrum. Gemstones may also be classified in terms of their "water". This is a recognized grading of the gem's luster, transparency, or "brilliance". Very transparent gems are considered "first water", while "second" or "third water" gems are those of a lesser transparency. Additionally, material or flaws within a stone may be present as inclusions.

Value

Gemstones have no universally accepted grading system. Diamonds are graded using a system developed by the Gemological Institute of America (GIA) in the early 1950s. Historically, all gemstones were graded using the naked eye. The GIA system included a major innovation: the introduction of 10x magnification as the standard for grading clarity. Other gemstones are still graded using the naked eye (assuming 20/20 vision).

A mnemonic device, the "four Cs" (color, cut, clarity, and carats), has been introduced to help describe the factors used to grade a diamond. With modification, these categories can be useful in understanding the grading of all gemstones. The four criteria carry different weights depending upon whether they are applied to colored gemstones or to colorless diamonds. In diamonds, the cut is the primary determinant of value, followed by clarity and color. An ideally cut diamond will sparkle, to break down light into its constituent rainbow colors (dispersion), chop it up into bright little pieces (scintillation), and deliver it to the eye (brilliance). In its rough crystalline form, a diamond will do none of these things; it requires proper fashioning and this is called "cut". In gemstones that have color, including colored diamonds, the purity, and beauty of that color is the primary determinant of quality.

Physical characteristics that make a colored stone valuable are color, clarity to a lesser extent (emeralds will always have a number of inclusions), cut, unusual optical phenomena within the stone such as color zoning (the uneven distribution of coloring within a gem) and asteria (star effects).

Apart from the more generic and commonly used gemstones such as from diamonds, rubies, sapphires, and emeralds, pearls and opal have also been defined as precious in the jewellery trade. Up to the discoveries of bulk amethyst in Brazil in the 19th century, amethyst was considered a "precious stone" as well, going back to ancient Greece. Even in the last century certain stones such as aquamarine, peridot and cat's eye (cymophane) have been popular and hence been regarded as precious, thus reinforcing the notion that a mineral's rarity may have been implicated in its classification as a precious stone and thus contribute to its value.

Today the gemstone trade no longer makes such a distinction. Many gemstones are used in even the most expensive jewelry, depending on the brand-name of the designer, fashion trends, market supply, treatments, etc. Nevertheless, diamonds, rubies, sapphires, and emeralds still have a reputation that exceeds those of other gemstones.

Rare or unusual gemstones, generally understood to include those gemstones which occur so infrequently in gem quality that they are scarcely known except to connoisseurs, include andalusite, axinite, cassiterite, clinohumite, painite and red beryl.

Gemstone pricing and value are governed by factors and characteristics in the quality of the stone. These characteristics include clarity, rarity, freedom from defects, the beauty of the stone, as well as the demand for such stones. There are different pricing influencers for both colored gemstones, and for diamonds. The pricing on colored stones is determined by market supply-and-demand, but diamonds are more intricate.

In the addition to the aesthetic and adorning/ornamental purpose of gemstones, there are proponents of energy medicine who also value gemstones on the basis of their alleged healing powers.

Additional Information

Gemstone symbolism refers to the cultural, historical, and spiritual associations between specific gemstones and concepts like healing, protection, love, and strength. This tradition dates back to ancient civilizations, where gemstones were prized not only for their beauty but for their perceived metaphysical properties. These beliefs influenced how gemstones were used — from royal jewelry and religious artifacts to personal talismans and medicinal treatments.

Today, many people choose gemstones based on these symbolic meanings to guide their purchases or for personal reasons, whether for birthstone jewelry or engagement rings.

Skeleton

Gist

A skeleton is the rigid framework of bones and cartilage that supports an organism's body, protects internal organs, and allows for movement; it can be internal (endoskeleton, like in humans and vertebrates) or external (exoskeleton, like in insects). The human skeleton, specifically, is an internal structure with 206 bones in adulthood, divided into the axial (skull, spine, ribs) and appendicular (limbs, girdles) parts, working with ligaments, tendons, and cartilage to provide shape, support, and facilitate motion. 

A skeletal system is necessary to support the body, protect internal organs, and allow for the movement of an organism. There are three different skeleton designs that fulfill these functions: hydrostatic skeleton, exoskeleton, and endoskeleton.

Summary

A skeleton is the structural frame that supports the body of most animals. There are several types of skeletons, including the exoskeleton, which is a rigid outer shell that holds up an organism's shape; the endoskeleton, a rigid internal frame to which the organs and soft tissues attach; and the hydroskeleton, a flexible internal structure supported by the hydrostatic pressure of body fluids.

Vertebrates are animals with an endoskeleton centered around an axial vertebral column, and their skeletons are typically composed of bones and cartilages. Invertebrates are other animals that lack a vertebral column, and their skeletons vary, including hard-shelled exoskeleton (arthropods and most molluscs), plated internal shells (e.g. cuttlebones in some cephalopods) or rods (e.g. ossicles in echinoderms), hydrostatically supported body cavities (most), and spicules (sponges). Cartilage is a rigid connective tissue that is found in the skeletal systems of vertebrates and invertebrates.

Details

Human skeleton is the internal skeleton that serves as a framework for the body. This framework consists of many individual bones and cartilages. There also are bands of fibrous connective tissue—the ligaments and the tendons—in intimate relationship with the parts of the skeleton. This article is concerned primarily with the gross structure and the function of the skeleton of the normal human adult.

The human skeleton, like that of other vertebrates, consists of two principal subdivisions, each with origins distinct from the others and each presenting certain individual features. These are (1) the axial, comprising the vertebral column—the spine—and much of the skull, and (2) the appendicular, to which the pelvic (hip) and pectoral (shoulder) girdles and the bones and cartilages of the limbs belong. A third subdivision, the visceral (splanchnocranium), comprises the lower jaw, some elements of the upper jaw, and the branchial arches, including the hyoid bone.

When one considers the relation of these subdivisions of the skeleton to the soft parts of the human body—such as the nervous system, the digestive system, the respiratory system, the cardiovascular system, and the voluntary muscles of the muscle system—it is clear that the functions of the skeleton are of three different types: support, protection, and motion. Of these functions, support is the most primitive and the oldest; likewise, the axial part of the skeleton was the first to evolve. The vertebral column, corresponding to the notochord in lower organisms, is the main support of the trunk.

The central nervous system lies largely within the axial skeleton, the brain being well protected by the cranium and the spinal cord by the vertebral column, by means of the bony neural arches (the arches of bone that encircle the spinal cord) and the intervening ligaments.

A distinctive characteristic of humans as compared with other mammals is erect posture. The human body is to some extent like a walking tower that moves on pillars, represented by the legs. Tremendous advantages have been gained from this erect posture, the chief among which has been the freeing of the arms for a great variety of uses. Nevertheless, erect posture has created a number of mechanical problems—in particular, weight bearing. These problems have had to be met by adaptations of the skeletal system.

Protection of the heart, lungs, and other organs and structures in the chest creates a problem somewhat different from that of the central nervous system. These organs, the function of which involves motion, expansion, and contraction, must have a flexible and elastic protective covering. Such a covering is provided by the bony thoracic basket, or rib cage, which forms the skeleton of the wall of the chest, or thorax. The connection of the ribs to the breastbone—the sternum—is in all cases a secondary one, brought about by the relatively pliable rib (costal) cartilages. The small joints between the ribs and the vertebrae permit a gliding motion of the ribs on the vertebrae during breathing and other activities. The motion is limited by the ligamentous attachments between ribs and vertebrae.

The third general function of the skeleton is that of motion. The great majority of the skeletal muscles are firmly anchored to the skeleton, usually to at least two bones and in some cases to many bones. Thus, the motions of the body and its parts, all the way from the lunge of the football player to the delicate manipulations of a handicraft artist or of the use of complicated instruments by a scientist, are made possible by separate and individual engineering arrangements between muscle and bone.

Additional Information

The skeleton is a remarkable organ that provides the body with a frame that is strong enough for protection, light enough for mobility, and adaptable for changing structural needs. The skeleton also serves metabolic functions as a storehouse for calcium and phosphorus, a buffering site for hydrogen ion excess, and a binding site for toxic ions such as lead and aluminum. When skeletal tissues are required to fulfill these latter functions, this may occur at the cost of structural integrity and lead to fractures. Once the adult skeleton has been formed, both the structural and metabolic functions are carried out largely by remodeling—removal and replacement of bone tissue at the same site in so-called bone multicellular units (BMU)—rather than modeling, which is formation of bone at sites where no prior resorption has occurred. Both processes do continue throughout life, however. In particular, modeling in the form of new periosteal apposition can occur with aging as a compensatory mechanism to the weakening of bone by the trabecular and endosteal loss and cortical porosity that occurs with increased resorption and inadequate formation in BMUs.

Colleges Quotes - I

1. And I think it's that time. And I think if you just step aside and Mr. Romney can kind of take over. You can maybe still use a plane. Though maybe a smaller one. Not that big gas guzzler you are going around to colleges and talking about student loans and stuff like that. - Clint Eastwood

2. Let reverence for the laws be breathed by every American mother to the lisping babe that prattles on her lap - let it be taught in schools, in seminaries, and in colleges; let it be written in primers, spelling books, and in almanacs; let it be preached from the pulpit, proclaimed in legislative halls, and enforced in courts of justice. - Abraham Lincoln

3. There's a level of service that we could provide when we're just at Harvard that we can't provide for all of the colleges, and there's a level of service that we can provide when we're a college network that we wouldn't be able to provide if we went to other types of things. - Mark Zuckerberg

4. With the changing economy, no one has lifetime employment. But community colleges provide lifetime employability. - Barack Obama

5. I've fought against transnational gangs. I took on the biggest banks and helped take down one of the biggest for-profit colleges. I know a predator when I see one. - Kamala Harris

6. I think, my own personal view is there should be higher and higher levels of autonomy; government should not interfere in setting up colleges, in running colleges. The market, the society will decide which is a good university, which is not a good university, rather than government mandating. - N. R. Narayana Murthy

7. Community colleges play an important role in helping people transition between careers by providing the retooling they need to take on a new career. - Barack Obama

8. There's a reasonable amount of traction in college education, particularly engineering, because quite a lot of that is privatized, so there is an incentive to set up new colleges of reasonably high quality. - Azim Premji.

Nauru

Gist

Nauru is a tiny, independent island republic in the South Pacific, known as the world's smallest republic, once rich from phosphate mining but now facing economic and environmental challenges from the mining's devastation, with high rates of obesity, yet possessing a resilient culture and unique language, relying on foreign aid and seeking sustainable development solutions.

Nauru is known for being the world's smallest republic, its history of immense wealth from phosphate mining (leading to extreme prosperity then economic collapse), severe environmental damage, hosting Australian offshore detention centers, and its struggles with obesity and economic sustainability, all while being a unique Pacific island nation with distinct culture and resilience.

Summary

Nauru, officially the Republic of Nauru, formerly known as Pleasant Island, is an island country and microstate in the South Pacific Ocean. It lies within the Micronesia subregion of Oceania, with its nearest neighbour being Banaba (part of Kiribati) about 300 kilometres (190 mi) to the east. Nauru is also known to have one of the highest obesity rates in the world, with around 70% of all adults over 18 being over 100kg (220 lb).

With an area of only 21 square kilometres (8.1 {mi}^{2}; 2,100 ha; 5,200 acres), Nauru is the third-smallest country in the world, larger than only Vatican City and Monaco, making it the smallest republic and island state, as well as the smallest member state of the Commonwealth of Nations by both area and population. Its population of about 10,800 is the world's third-smallest (not including colonies or overseas territories). Nauru is a member of the United Nations, the Commonwealth of Nations, and the Organisation of African, Caribbean and Pacific States.

Settled by Micronesians circa 1000 BCE, Nauru was annexed and claimed as a colony by the German Empire in the late 19th century. After World War I, Nauru became a League of Nations mandate administered by Australia, New Zealand, and the United Kingdom. During World War II, Nauru was occupied by Japanese troops and was bypassed by the Allied advance across the Pacific. After the war ended, the country entered into United Nations trusteeship. Nauru gained its independence in 1968. At various points since 2001, it has accepted aid from the Australian Government in exchange for hosting the Nauru Regional Processing Centre, a controversial offshore Australian immigration detention facility. As a result of heavy dependence on Australia, some sources have identified Nauru as a client state of Australia.

Nauru is a phosphate-rock island with rich deposits near the surface, which allowed easy strip mining operations for over a century. However, this has seriously harmed the country's environment, causing it to suffer from what is often referred to as the "resource curse". The phosphate was exhausted in the 1990s, and the remaining reserves are not economically viable for extraction. A trust established to manage the island's accumulated mining wealth, set up for the day the reserves would be exhausted, has diminished in value. To earn income, Nauru briefly became a tax haven and illegal money laundering centre.

Details

Nauru, island country in the southwestern Pacific Ocean. It consists of a raised coral island located in southeastern Micronesia, 25 miles (40 km) south of the Equator.

The island is about 800 miles (1,300 km) northeast of the Solomon Islands; its closest neighbor is the island of Banaba, in Kiribati, some 200 miles (300 km) to the east. Nauru has no official capital, but government offices are located in the district of Yaren.

Most of Nauru rises somewhat abruptly from the ocean, and there are no harbors or protected anchorages. A fairly fertile but relatively narrow belt encircles the island and surrounds the shallow inland Buada Lagoon. Farther inland, coral cliffs rise to a plateau 100 feet (30 meters) above sea level, with the highest point at about 213 feet (65 meters). The plateau is largely composed of rock phosphate, leached from guano, or bird droppings. The mineral deposit covers more than two-thirds of the island, and its extraction has left irregular, pinnacle-shaped outcrops of limestone that give the landscape a forbidding, otherworldly appearance.

Nauru is the third smallest country in the world.

Nauru’s climate is tropical, with daytime temperatures in the low 80s F (about 28 °C), tempered by ocean breezes. Rainfall, averaging about 80 inches (2,000 mm) annually, is extremely variable, and prolonged droughts occur. The only locally available water is collected from roof catchment systems, and water is imported as ballast on ships returning to Nauru for loads of phosphate. There are no rivers or streams.

Soils are generally poor and highly porous, and the irregular rainfall limits cultivation to the coastal belt and the lagoon’s fringe. Phosphate mining has ravaged the interior of the island, leaving about four-fifths of it uninhabitable and uncultivable. Subsistence crops, consisting mainly of coconut palms, pandanus, bananas, pineapple, and some vegetables, are not adequate to support the population; the land does yield a great variety of plants and trees, however. Nauru is a favorite stopover point for migratory birds, and chickens have been introduced. There was an absence of mammals until rats, mice, cats, dogs, and pigs were also imported.

People

Most of the island’s residents are indigenous Nauruans. There are small numbers of I-Kiribati (Gilbertese), Australians, New Zealanders, Chinese, and Tuvaluans; many members of the latter two groups were recruited as workers by the phosphate industry. Nauruan is the national language. No adequate written grammar of the language has been compiled, and its relationships to other Micronesian languages are not well understood. English is widely spoken. Nauru is considered one of the most Westernized countries in the South Pacific.

Missionization came later to Nauru than to many other Pacific islands. The first Protestant evangelist arrived in 1899 and was followed three years later by the first Roman Catholic missionary. Today more than four-fifths of Nauruans are Christians; more than half the total population is Protestant (mostly members of the Nauru Congregational Church), and one-third is Roman Catholic.

The settlement pattern on the island is dispersed. People are scattered along the coastal zone, and there is one small village, Buada, inland near the lagoon.

Economy

Agriculture (with the exception of coffee and copra plantations along the coastal and lagoon perimeters), fishing, manufacturing, and tourism are of minor value to the overall economy. However, Nauru has an exclusive economic zone extending 200 miles (320 km) offshore. The sale of commercial fishing licenses began to bring in a steady revenue during the 1990s.

Phosphate has been mined on Nauru since 1907. For decades it was Nauru’s main resource and sole export, dominating the island’s economy, and its quality was the highest in the world. The phosphate industry and government services together provided almost all of the island’s salaried employment. For much of the 20th century the phosphate industry was owned and operated by a corporation jointly managed by the British, Australian, and New Zealand governments. The government of independent Nauru gained control of phosphate operations in 1970, and in the 1980s Nauru was for a time one of the wealthiest countries in the world in terms of gross domestic product per capita. Landowners received royalties from the phosphate earnings, and many Nauruans were unemployed by choice. By the late 20th century, however, the phosphate deposits were quickly becoming exhausted, and Nauru experienced a severe drop-off in earnings, leading to the country’s near bankruptcy by the early years of the 21st century. Nauru struggled to develop other resources and find alternative sources of income. However, the country experienced some economic respite late in the first decade of the 2000s when repairs and improvements to mining-related infrastructure expedited the extraction and export of the remaining primary phosphate deposits and allowed the more difficult extraction of secondary phosphate deposits.

In the early 21st century Nauru agreed to temporarily house hundreds of Australia-bound asylum seekers while they awaited the processing of their applications. In exchange, the Australian government provided millions of dollars in aid to Nauru.

Virtually all food, water, and manufactured goods are imported. Australia supplies nine-tenths of Nauru’s imports; far smaller amounts come from New Zealand, Fiji, and Japan. Nigeria receives almost half of Nauru’s exports, and South Korea and Australia combined take another one-third. With the exception of those levied on alcohol and tobacco, there are no import duties. There is no income tax.

Nauru has its own banking system; the Bank of Nauru is wholly owned and operated by the government. The financial sector grew in importance after the 1980s as the island became known as an offshore banking center and tax haven. Beginning in 1999, amid allegations that it was a money-laundering conduit for organized crime and terrorist organizations, the financial sector underwent a series of reforms to increase its transparency. As one consequence of its colonial history, Nauru is within the Australian monetary system, and Australian currency is the country’s legal tender.

Transportation on the island is good. A paved road system links all villages. Surface transportation to other destinations is difficult. Because there are no wharves or natural harbors, passengers and cargo are shuttled by barge between oceangoing vessels and a small artificial anchorage. Most regional and international travel is by air. Nauru’s sole airport is located in Yaren district. In 1970 the country launched its national airline, control of which was transferred in 1996 to a government-owned corporation.

Government and society

Nauru’s constitution, implemented with independence in 1968, calls for broadly phrased fundamental rights and freedoms for individuals and a government that combines parliamentary and presidential systems. The parliament, whose members are elected by Nauruan citizens age 20 and older, has a tenure of three years unless dissolved by a vote of no confidence. It elects the president, who is both head of state and head of government. The president appoints a cabinet from the parliament. In 1999 Nauru became a full member of both the Commonwealth and the United Nations.

The tripartite judicial system comprises a Supreme Court, a District Court, and a Family Court. The Supreme Court, presided over by a chief justice, has both original and appellate jurisdiction. At Nauru’s request, final appeals may be taken to the High Court of Australia.

Basic services in education and health are provided free to all citizens, though services have been reduced as a result of the country’s changing economic fortunes. There is no government social security system. Education is compulsory between ages 6 and 16. The government provides several kindergartens and elementary and secondary schools. The Roman Catholic mission has its own school system at the same three levels. Traditionally, students have gone abroad, mainly to Australia, for higher education.

Additional Information:

Overview

Nauru is an island republic in the Pacific Ocean, 42 kilometers south of the equator and 4,000 kilometers northeast of Sydney, with a total land area of 21 square kilometers. Nauru has a population of approximately 13,000 people.

Political overview

Nauru is one of the world's smallest independent states. Its constitution, adopted upon gaining independence in 1968, established it as a republic with a Westminster-style parliamentary system of government. The President is elected by, and responsible to, the unicameral parliament and is both head of government and head of state.

As there are no political parties in Nauru, all Members of Parliament (MPs) stand as independents. MPs are elected every three years by Nauruan citizens over the age of 20. At its first sitting, where possible, parliament chooses a Speaker, a Deputy Speaker and chairs of committees before proceeding to elect the President from among the remaining members. The President then appoints a minimum of four members of parliament to join him or her in forming a cabinet. On 30 October 2023, His Excellency, David Adeang was appointed as President. Nauru's elections are held every three years, its next elections are due in 2025.

Bilateral relations

Australia and Nauru have a deep, long-standing relationship, underpinned by a shared history and people-to-people links. Australia is Nauru’s largest trade, investment, security and development assistance partner.

In December 2024, Nauru and Australia signed the Nauru-Australia Treaty. The Treaty elevates our long-standing relationship to an integrated partnership which supports Nauru’s economic security and resilience. It underscores Australia and Nauru's shared commitment to delivering Pacific-led solutions to meet our region's challenges.

Under the Treaty, Australia will provide $100 million over five years in budget support and $40 million over five years to support Nauru’s policing and security. The Treaty officially entered into force on 19 September 2025.

In September 2017, Nauru and Australia signed a Memorandum of Understanding on security cooperation which affirmed Australia's position as Nauru's primary security partner. Australia works in close cooperation with Nauru to address domestic and transnational security challenges whilst always having regard to the sovereignty and best interests of Nauru.

In September 2012, Australia established a regional processing centre in Nauru for the purpose of processing asylum seekers' international protection claims. In October 2021, Australia and Nauru signed a Memorandum of Understanding on the Enduring Regional Processing Capability in Republic of Nauru.

People-to-people links

Every year, a number of Australia Award and Australia Award Pacific Scholarships are offered for Nauruans to study abroad at selected Australian and Pacific regional universities.

Nauru participates in Australia's Pacific Australia Labour Mobility (PALM) scheme, connecting workers from Nauru and other Pacific islands with Australian employers experiencing labour shortages, typically in rural and regional Australia.

Nauru participates in Australia’s Pacific Engagement Visa, which offers access to Australian schools, tertiary education, health care and employment market.

Australia and Nauru also enjoy strong diaspora, alumni and professional linkages.

Economic overview

Nauru's economy faces significant constraints common to other small island states. These include its small size, remoteness and limited natural resources outside of fisheries.

Pelagic fish abound in Nauruan waters, but Nauru has yet to establish a substantial fishing industry of its own. Fees from fishing licenses issued to distant water fishing nations are an important source of revenue for Nauru.

Australia contributes financially to, and takes a shared management role in, the Intergenerational Trust Fund for the People of Nauru. The fund aims to provide a future revenue stream for Nauru to supplement domestic revenue in anticipation of current revenue declining over the next 20 years.

Trade and investment

Australia is Nauru's principal import source. Major Australian merchandise exports to Nauru include meat, motor fuel and civil engineering equipment and parts. For more information see the Nauru economic fact sheet.

Skull

Gist

A skull is the bony structure forming the head, protecting the brain and supporting facial features, but it also symbolizes mortality, knowledge (the mind), or danger (skull and crossbones) across cultures, representing the fragility of life or a warning. It consists of cranial bones (braincase) and facial bones, connected by immobile sutures, with the movable jaw (mandible) being a key part.

The rounded brain case surrounds and protects the brain and houses the middle and inner ear structures. In the adult, the skull consists of 22 individual bones, 21 of which are immobile and united into a single unit. The 22nd bone is the mandible (lower jaw), which is the only moveable bone of the skull.

Summary

Skull is a skeletal framework of the head of vertebrates, composed of bones or cartilage, which form a unit that protects the brain and some sense organs. The upper jaw, but not the lower, is part of the skull. The human cranium, the part that contains the brain, is globular and relatively large in comparison with the face. In most other animals the facial portion of the skull, including the upper teeth and the nose, is larger than the cranium. In humans the skull is supported by the highest vertebra, called the atlas, permitting nodding motion. The atlas turns on the next-lower vertebra, the axis, to allow for side-to-side motion.

In humans the base of the cranium is the occipital bone, which has a central opening (foramen magnum) to admit the spinal cord. The parietal and temporal bones form the sides and uppermost portion of the dome of the cranium, and the frontal bone forms the forehead; the cranial floor consists of the sphenoid and ethmoid bones. The facial area includes the zygomatic, or malar, bones (cheekbones), which join with the temporal and maxillary bones to form the zygomatic arch below the eye socket; the palatine bone; and the maxillary, or upper jaw, bones. The nasal cavity is formed by the vomer and the nasal, lachrymal, and turbinate bones. In infants the sutures (joints) between the various skull elements are loose, but with age they fuse together. Many mammals, such as the dog, have a sagittal crest down the centre of the skull; this provides an extra attachment site for the temporal muscles, which close the jaws.

Details

The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate.

In a human, the skull comprises two prominent parts: the neurocranium and the facial skeleton, which evolved from the first pharyngeal arch. The skull forms the frontmost portion of the axial skeleton and is a product of cephalization and vesicular enlargement of the brain, with several special senses structures such as the eyes, ears, nose, tongue and, in fish, specialized tactile organs such as barbels near the mouth.

The skull is composed of three types of bone: cranial bones, facial bones and ossicles, which is made up of a number of fused flat and irregular bones. The cranial bones are joined at firm fibrous junctions called sutures and contains many foramina, fossae, processes, and sinuses. In zoology, the openings in the skull are called fenestrae, the most prominent of which is the foramen magnum, where the brainstem goes through to join the spinal cord.

In human anatomy, the neurocranium (or braincase), is further divided into the calvaria and the endocranium, together forming a cranial cavity that houses the brain. The interior periosteum forms part of the dura mater, the facial skeleton and splanchnocranium with the mandible being its largest bone. The mandible articulates with the temporal bones of the neurocranium at the paired temporomandibular joints. The skull itself articulates with the spinal column at the atlanto-occipital joint. The human skull fully develops two years after birth.

Functions of the skull include physical protection for the brain, providing attachments for neck muscles, facial muscles and muscles of mastication, providing fixed eye sockets and outer ears (ear canals and auricles) to enable stereoscopic vision and sound localisation, forming nasal and oral cavities that allow better olfaction, taste and digestion, and contributing to phonation by acoustic resonance within the cavities and sinuses. In some animals such as ungulates and elephants, the skull also has a function in anti-predator defense and sexual selection by providing the foundation for horns, antlers and tusks.

Additional Information:

Overview

What is the skull?

Your skull is the part of your skeleton that holds and protects your brain. It also holds or supports several of your main sensory organs, like your eyes, ears, nose, tongue and more. The skull’s medical name is the cranium.

When you’re born, your skull is mostly formed but not quite complete. Some parts of it, called fontanelles, are softer and more flexible. You can see an example of this in the soft spot at the top of an infant’s head. The fontanelles allow your brain and skull to grow and develop.

There are also places where the left and right sides of a bone (like the parietal bone) or multiple bones join. Those are called sutures. These can change throughout your lifetime, even well into adulthood. Some sutures fuse solid while you’re an infant. Others may not fuse until your 60s.

Function:

What does the skull do?

Your skull has two main jobs:

* Protection. The bony structure of your skull protects your brain and critical sensory organs like your eyes and ears.
* Structure. Your skull is what gives your face and head their shape. It has many attachment points for muscles to anchor to. It’s one of the most important things that determines what your face looks like.

Anatomy:

What are the parts of the skull?

Your skull sits at the top of your spinal column, inside your neck. While it might seem like your skull is just one structure, there are two distinct parts of it. They are the:

* Cranial vault (neurocranium or calvarium). This surrounds and protects your brain.
* Facial skeleton (viscerocranium). This supports and holds the various parts of your face.

Cranial vault anatomy

This part of your skull consists mainly of the calvarium. That includes the:

* Frontal bone. This is a single, seamless bone. It gives your forehead its structure.
* Sphenoid bone. This is a single bone below and in front of your brain, but behind the bones making up your face. It also forms part of the lower rear of your eye sockets.
* Ethmoid bone. This is a single bone that fills in a heart-shaped, hollow space in the sphenoid bone at the lower front of your brain.
* Temporal bones. There are two of these bones, one on each side. Each has a small opening where your ear canal passes through the skull.
* Parietal bones. These are a pair of bones that join together at a seam called the sagittal suture. They form the upper middle and upper back of your skull.
* Occipital bone. This is a single seamless bone at the lower back of your skull.

Facial skeletal anatomy

The facial skeleton is at the front of your skull. It’s a group of bones that support and give your face its structure. The bones of this part of your skull are:

* Nasal bones. These form the bridge of your nose. They overlap slightly with the maxilla and the forward part of the ethmoid bone.
* Vomer. This bone is like the floor of the nasal cavity space right behind your nose.
* Lacrimal bones. These form the central-lower inside portion of your eye socket.
* Palatine bones. These are a small section of the bottom of your eye socket’s interior.
* Zygomatic bones. These form the outer lower edge of your eye socket.
* Maxilla. This single bone forms the central part of your cheekbones on both sides. It also is what makes up the central-lower-forward part of your eye socket. It also makes up your upper jaw. It overlaps slightly with the forward part of the ethmoid bone.
* Mandible. This single bone makes up your lower jaw. It’s the only bone of your skull that moves.

Conditions and Disorders:

What are the common conditions and disorders that affect the skull?

Your skull is prone to a wide range of conditions, and many of them are congenital. That means you have the condition when you’re born. Examples of congenital skull conditions include:

* Anencephaly
* Apert syndrome
* Carpenter syndrome
* Cleidocranial dysplasia
* Craniosynostosis
* Crouzon syndrome
* Encephalocele
* Goldenhar syndrome
* Hemifacial microsmia
* Microcephaly
* Micrognathia
* Pfeiffer syndrome
* Prognathism
* Scaphocephaly

There are also several conditions and injuries that you can develop at any time in life that affect your skull. Examples include:

* Temporomandibular joint disorders
* Jaw cysts and tumors, some of which can be jaw cancer
* Dental trauma, including a dislocated jaw or broken jaw
* Skull fractures and/or related concussions and traumatic brain injuries (TBIs)

Common signs or symptoms of skull conditions

The common signs and symptoms of skull conditions vary widely. Congenital skull conditions usually cause differences in skull appearance and/or development. That can cause distinctive facial or head appearances.

Non-congenital skull conditions can cause the following:

* Head pain, especially headaches
* Jaw popping or jaw pain
* Brain symptoms, like confusion or coma
* Bruising, often with specific patterns like raccoon eyes (a key sign of a skull fracture)

Common tests to check the skull

Diagnostic imaging tests are the main way to diagnose skull conditions. These include:

* X-rays, including dental x-rays
* CT scans
* MRI

Providers who suspect congenital conditions that affect your skull often recommend genetic testing. It can detect specific genetic variations that could help providers find the right diagnosis.

Other tests are possible, depending on your symptoms, health history and other factors. Your healthcare provider is the best person to tell you what tests they recommend and why.

What are some common treatments for skull conditions?

The treatments for skull conditions depend on which condition you have. Your health, personal history and circumstances can also be factors. Ask your healthcare provider about the treatment options for your specific case.