DEXA Scan - Knowing Its Importance For Osteoporosis Patients!

What is DEXA or DXA Scan : 

The DEXA Scan or bone density test, also known as the Dual Energy X-ray Absorptiometry Scan, is the gold standard test for detecting osteoporosis.

Why do we need DEXA scan : 

It is needed to detect osteoporosis. Osteoporosis is a disease that affects the bones. In this condition, the bones literally become porous with loss of calcium from the internal structure of bone causing them to become weak and brittle. 

This occurs at an earlier age and more commonly in women compared to men. The reason being women undergoing weakening of bones due to menopausal osteoporosis as well as senile osteoporosis. In women estrogen hormone levels fall with menopause and that causes loss of calcium from bone along with decreased absorption of calcium from food intake. This loss in bone strength occurs most rapidly in the first ten years after menopause. 

Senile osteoporosis affects both men and women and is the weakening of bones due to ageing and comes on much later in life.

Osteopenia or osteoporosis detected with DEXA scan means that person has a higher risk of fracture and can get a fracture even with a minor injury or even without an injury

Who needs it : 

Anybody who has increased fracture risk ( as assessed by the doctor ) or anybody who has a had a fragility fracture needs a DEXA scan. Among people who do not have a fracture or increased fracture risk, women above the age of 65 and men above the age of 70 should have the scan done as a screening measure. Other factors can contribute to the weakening of bones and people with these conditions may also need the DEXA scan. These conditions include kidney disease, hyperparathyroidism which happens due to overactivity of the said gland, liver disease, intestinal disease, malabsorption syndromes, vitamin D deficiency and dietary calcium deficiency, use of thyroid medication and use of steroids.

How is it done. :

Central DEXA is the most accurate way of doing the scan. It is a simple, quick and non-invasive scan that does not need any injection or discomfort. You just lie down in a machine and it sends a low energy beam into your body and the receptor of the machine measures the radiation absorbed by the bones in your body and gives us a measurement of the density of the bone. The radiation used in this test is less than 1/10th of the radiation used in a chest x-ray.

How is it read :

Bone Density Scores: The reading obtained from the DEXA scan for a particular patient is matched with population-based scores already fed into the software and from that T score and Z scores are obtained. Z scores are age-matched while T score is your bone density compared to a 30-year-old adult.T score is used to label one as normal, osteopenic or having osteoporosis.

What after the test :

Treatment is based on patient characteristics and the T score of a patient. The treatment options include bisphosphonates, teriparatide, denosumab, raloxifene along with calcium.