What is densitometry
Analyses And Studies / / August 12, 2017
- principle of research and types
- Indications for
- How is densitometry
study principle and types
Densitometry - a technique of instrumental diagnostics, by means of whichconducted qualitative and quantitative assessment of bone density.To do this, it is identified a number of indicators, including relative density, the architecture of (spatial structure), the thickness of the cortical layer.Depending on the principle and mechanism for determining the parameters, there are two main types of research:
- X-ray densitometry - precision technique based on the fact that X-rays are retained to a greater extent when passing through dense bone tissue witha high concentration of mineral salts (in particularall calcium salts).According to the degree of absorption of X-rays performed mathematical quantification of its mineralization.Also, this technique allows to visualize the structure.
- Ultrasonic densitometry kostey- is indirect method of determining the density.Its essence lies in the fact that the speed of passage of the ultrasonic wave (a sound wave with a high frequency of 3 MHz) is different in areas with different densities of tissue.densitometer apparatus generates ultrasound of a certain frequency, which passes through the bone tissue in the test area of the body with the subsequent registration of the sensor.
There are also subtypes X-ray densitometry, including the combined use of imaging (MRI or CT).Selection methodology of this survey is determined by the clinical features, the need to accurately calculate the severity of salinity reduction in the diagnosis of osteoporosis.Ultrasound densitometry, due to the simplicity and safety of the study, is a screening method that allows detection of osteoporosis can be performed on an outpatient basis.
main indication for DXA is osteoporosis - weakening bones, due to a decrease in the concentration of mineral salts.Such a condition results in a number of causal factors, which are indications of a study:
- Pregnancy - for normal growth and development of the fetus necessary mineral salts.When there is insufficient stock in pregnant women may be their "washing out" of the bone to provide the fetus with developing osteoporosis.
- Metabolic disturbances in the body, in which the exchange rate is changed calcium and phosphorus needed for bone strength.
- Pathology of the spine - osteochondrosis of lumbar spondylolisthesis, fractures or joints subluxation spinous processes, which often develop as a result of inadequate mineralization.
- Diseases of the endocrine system, the result of which is hidden or overt osteoporosis with the development of complications such as bone fractures.
- prolonged hormonal treatment, side effects of which may be a decrease in the density and salinity.
- Neurological pathology, recurrent or persistent back pain of unknown etiology.
- Repeated bone fracture, especially if this is accompanied by a hip injury.
- Monitoring the effectiveness of osteoporosis therapy of various etiologies.
- assessment of the adequacy of the body to ensure the child's calcium and phosphorus salts during periods of intensive growth of long bones in length.
also for people over 40 years shows the passage of a screening study with a frequency of 1 every 2 years.This allows time to identify osteoporosis at an early stage and start effective treatment.
How is densitometry
This test is painless, simple and not traumatic procedure.Before you go through densitometry, you must perform a series of recommendations, which include:
- eve for a few days to eliminate intake of calcium-rich foods (cheese) or drugs with salts of phosphorus and calcium.
- If shortly before the alleged carrying out the procedure (with the exception of ultrasound densitometry) X-ray examinations were performed (especially with the use of a mixture of barium as a contrast agent), you must notify the physician.Implementation of the study will be rescheduled for a period of time determined by your doctor.
- When pregnancy conducting X-ray densitometry is possible to diagnose osteoporosis is performed only possible ultrasound densitometry.
- In the combination studies with magnetic resonance imaging, it is imperative to exclude the presence in the body of various metallic implants or prostheses (dental crowns, held metal osteosynthesis).If any is carried out X-ray or ultrasound bone.
The procedure itself is not long, while its implementation is about half an hour.When performing densitometry patient is placed on a special table, position of the body depends on the test area of the body, which is placed over the device sensor.During the procedure directly, you must try to keep the body immobility.Special Recommendations on the regime after performing densitometry not.
two osnvnyh density indicator is calculated after the procedure, which include:
- T-score - the ratio of the result of bone density to the average (normal) indicator;
- Z-score - the ratio of the density of bones in the age norm.
Reducing these figures indicates osteoporosis process in the bone.Lower values indicate a more pronounced osteoporosis.
Determination of density, structure and mineralizatsiikostnoy tissue is an objective method of research.Find out where to go densitometry, can be a doctor orthopedist.Usually, it is well-versed in the presence of vehicles in a variety of medical clinics for X-ray or ultrasound densitometry.