What is bone densitometry | Medical tests

Bone densitometry is a test used to measure the density of calcium in our bones.

Bone densitometry

Bone densitometry is a technique that allows you to measure the density of calcium which have bones. It is a useful test to detect osteoporosis at an early stage, and also serves to evaluate the response to treatment in people who suffer from it. It is a technique that is easy to perform for speed, cost and convenience for the patient, since it is not painful or require hospital admission. However, it is not shown to be necessary to carry out this test to all people at risk of osteoporosis, will only be useful to perform it to some specific groups of people.
They can be used to perform bone densitometry x-ray, ultrasound or radioactive isotopes. The oldest technique uses x-rays and is still today the most common because it is the most well known and easy to perform, is called to this technical specific DXA or DEXA. Densitometry using doses of x-ray very small and the damage to the cells of our organism is almost nil, in addition, the device is able to focus all of its broadcast in a single point thanks to a few special filters.
The test is usually performed on a single bone, normally hip or lower vertebrae of the spinal column. In some adults and children held throughout the body. The measuring device gets an image that detects the amount of calcium from bone and compared to normal values.

When a bone densitometry is made

Today it is in discussion when a bone densitometry should be performed. However, there are groups of individuals where densitometry seems to be a beneficial test to assess the loss of
Postmenopausal women with severe symptoms, without hormonal treatment and low consumption of estrogens (which are found in soya, for example).
Postmenopausal women who smoke or have smoked throughout his life, since the tobacco accelerates the loss of calcium in bones.
Men and women with diseases involving bone loss (multiple myeloma, diabetes type 1, renal or hepatic disease...).
Older people who have a history of hip or spine fracture family.
People who consume drugs causing loss of calcium in the bone (corticoids, antiepileptic drugs, alcohol, etc).
Anyone who have hyperparathyroidism, a disease where parathyroid hormone is elevated and makes the bones to release calcium have into the blood.
People who have had a fracture in any part of the body after a not very sharp blow, which makes us suspect that they are too fragile bones.
Children who suffer from genetic diseases that affect the formation of bone, such as osteogenesis imperfecta.

Preparation for bone densitometry

If you will make a bone densitometry these are the issues that you must consider when go well prepared for the test:
Duration: usually takes very little time, about 15-20 minutes at most.
Entry: not require income, can be done on an outpatient basis.
Is necessary to be accompanied?: not, is a painless and not invasive, so you can only attend the clinic and return in the same way.
Drugs: is not necessary to take any prior medication. You must tell your doctor all the medicines that you take so that you assess whether or not the test is required. If you take calcium supplements you should not eat them 24 hours before the test.
Food: you can eat normally, it is not necessary to go on fasting to the clinic.
Clothing: is best to attend the test with comfortable clothes, since there will change by a bathrobe to avoid belts and metal objects that might interfere with the measurement. Jewelry, glasses and false teeth also upset and should be removed.
Documents: there is any type of document, but may give you results of bone densitometry in the time of completion of the test and you need to save them.
Contraindications: only pregnancy and lactation may be relative contraindications.
Pregnancy and lactation: is not recommended to perform bone densitometry to pregnant women, since x-rays are used. Although the possible harm to the fetus is minimal is not considered to be an essential test for risk. Breast-feeding is not a contraindication, radioactive isotopes are used.

How bone densitometry

When you arrive at the clinic they ask you that passes to a dressing room where you can change your clothes for a more comfortable gown and leave your personal belongings. Sometimes you don't need to wear a gown and you can spend with your street clothes, provided you have no metallic elements that disturb. You will then go to the room where the device that is bone densitometry, you'll see a table or Chair and beside a machine with two arms, one going down the stretcher and the other above.
Then you recostarás you on the table differently depending on the area that want to measure. If hip is measured, the foot is placed in a sleeve that will make you to rotate the leg to properly position the hip. If you measure the spine, legs will be higher to support back on the couch. Once you are properly placed will not need to worry about anything else, just be relax and remain still.
The sanitary technician will handle the machine and begin to measure the bone sent bone density x-rays that will leave the lower arm and collected on the upper arm. Throughout this process you won't feel anything.
A few minutes later the sanitary technician will tell you that the test has finished and you can already get up from the couch. It may also prompted you to wait a few minutes in the waiting room to give you the results in a report, or perhaps send them is the doctor directly, it depends on if the radiologist doctor can write the report at the time or not.
After the test you won't feel anything unusual in the area that have measured the density of bone. You can collect your things from the dressing room and leave the clinic in the same way that you've come. It may be necessary to perform this test every two years if requested to verify the effectiveness of a treatment or detect osteoporosis at an early stage.

Complications of bone densitometry

Complications in bone densitometry are virtually non-existent. Yes it is true that there is a risk associated with radiation to always use x-ray and that therefore the usual in this type of testing, precautions as it happens in chest x-rays or CT, especially if the woman who undergoes the test might be pregnant. However, the radiation dose is much lower than in routine tests of x-ray and its theoretical complications are much less important.
Unlike that in other radiological tests do not need to use lead against radiation in any case, since the especially sensitive organs (thyroid, testicles or ovaries) not receive x-rays directly.

Bone densitometry results

Bone densitometry results are obtained at the same time make it, but we need a physician who specializes in this type of evidence to interpret them.
The doctor who usually take care of densitometry is the radiologist, oversees the performance of the test and analyses the results obtained writing a report that will deliver the doctor has ordered her (rheumatologist, family physician, endocrinologist...).
In the report, there will be a series of statistics which highlight two important:

T-score

This data indicates the density of calcium that has the bone in relation to the maximum amount that would have a bone in a similar person in a particular moment of her life:

• If the score is greater than - 1, we can consider it as normal.
• When the score is between - 1 and - 2'5 say that the person presents osteopenia, or bone density lower than normal.
• We believe that you have osteoporosis when the score is less than - 2'5. This is very important to assess the risk that have that person to suffer a fracture in one of his bones.

Z-score

This data indicates the density of calcium that has the bone in relation to the average of the population of people that suits you according to your age, sex, weight and size. This score itself does not diagnose osteoporosis because it is a fact that varies greatly from one person to another, but if it is outside the normal ends serves to alert us and ask for further tests.

Published for educational purposes