All About Thyroid Tests

The different types of thyroid tests and their diagnosis

Contributed by- Dr. Dhrity Vats

Our country carries a heavy burden of thyroid disorders affecting a rather disturbingly large number of people, especially women. Every one out of 10 adults in India suffers from thyroid problems, although with such a huge incidence rate the awareness of thyroid problems is really scarce in our country.

A lot has been written and discussed about thyroid problems but still most of us prefer to live in the world of illusion. Ignoring the problem is never going to solve it, the correct knowledge of the disorders and the ways to diagnose will help in understanding your health better. Let us discover the various thyroid problems and various tests used to diagnose them inorder to tackle them correctly.

 

What Is Thyroid?

Thyroid is a butterfly shaped gland located at the back of our throats which releases thyroid hormones that regulates body processes like respiration, body temperature, hormonal levels, moods, digestive and other metabolic processes. Some of the most common thyroid problems are:

  • Hyperthyroidism – when thyroid gland produces too many hormones
  • Hypothyroidism – when thyroid gland produces not enough hormones
  • Thyroid cancer
  • Thyroid enlargement i.e. goiter
  • Nodules or lumps in thyroid
  • Dysfunction of thyroid gland due to drugs

 

How Does Thyroid Gland Function?

The thyroid gland releases two major major hormones triiodothyronine (T3) and thyroxin (T4).  The thyroid gland utilises the iron in the body to produce thyroid hormones and the pituitary gland releases thyroid stimulating hormone (TSH) to regulate the thyroid hormone levels in the body. If the level of T4 hormone falls below desired level the thyroid stimulating hormone TSH signals the thyroid gland to produce more T4 hormones. Once the T4 level reaches the reference level, pituitary gland shuts the TSH production.

 

What Are The Symptoms Of Thyroid Disorders?

Any alterations in the levels of TSH , T4 or T3 is indicated through symptoms, the body has it’s own way of communicating that everything is not okay. The symptoms need proper attention and must be taken seriously. Some of the common symptoms identified with hypothyroidism are;

  • fatigue
  • sensitivity to cold
  • dryness
  • flaky skin
  • hair loss
  • slow heart rate
  • constipation
  • unexplained weight gain

Some common symptoms of hyperthyroidism are;

  • excessive seating
  • feeling hungry constantly
  • protrusion of eyes
  • irregular menstrual behavior
  • weakness
  • abnormal weight loss

 

The above symptoms accompanied with enlarged thyroid gland with pain in swallowing and changes in the voice often indicates towards thyroid cancer.

 

Tests For Thyroid

Thyroid disorders can be diagnosed with the help of several tests, the tests are advised on the basis of symptoms experienced to help diagnose the correct problem and get the proper treatment. A proper diagnosis for thyroid problems starts initially with thyroid blood tests, for further diagnosis of serious thyroid problems or other related health complications tests like Ultrasound, CT scan, MRI, RAI- U are medically advised.

Thyroid Blood Test

The blood tests includes tests to check the level of three main hormones TSH, T4 and T3 in the body. A non-fasting blood sample is needed to evaluate and to monitor any discrepancy in the thyroid levels. The normal range of the three main thyroid hormones are mentioned below:

 

   Hormones                          Normal Range
     TSH                                0.4 to 4.0mU/l (milliunits per litre)
     T4                                   9.0 to 25.0pmol/l (picomoles per litre)
     T3                                   3.5 to 7.8pmol/l (picomoles per litre)

 

Hypothyroidism – A high level of TSH and low level of T4 confirms this disorder

Hyperthyroidism – A low level of TSH and high T4 & T3 confirms this disorder

A blood test is recommended every three months to check for the varying changes in the levels of TSH , T4 or T3.

 

Thyroid Ultrasound

A thyroid ultrasound is generally advised incase of presence of nodule or cyst in the thyroid gland. The high frequency sound waves of the ultrasound gives a the clear picture of the size of the cyst or nodule and also helps in the diagnosing if the nodule is made up of fluid or solid mass. An ultrasound is advised by the doctor to help in the correct diagnosis.

 

CT Scan 

Incase of serious thyroid problems which are not easily diagnosed with an ultrasound are observed in the computed tomography or more commonly known as the ‘CT Scan’. A doctor usually advises a CT Scan to diagnose an abnormal growth of nodule or goitre and to determine the size of the goitre.

 

MRI

Magnetic Resonance Imaging (MRI) is done to evaluate the size of the gland and to monitor the change in the size of goitre caused due to several factors including use of certain drugs. This does not evaluate the functioning of the gland but just changes in the shape and size of the gland.

 

Radioactive Iodine Uptake (RAI-U)

Radioactive Iodine Uptake is used to diagnose thyroid cancer and severe cases of hyperthyroidism. A small dosage of radioactive iodine 123 (called I-123) is given in the form of pill or liquid which has iodine content, the thyroid gland absorbs the iodine and a camera is placed on the neck which captures the emitted rays through the skin which further aids in diagnosing the problem.  A radioactive iodine 131 is also used in some cases of thyroid cancer.

 

The easiest and most common test generally done to diagnose thyroid problems is thyroid scan which evaluates the ranges of TSH, T4 & T3 in the body. It is the quickest and best way to confirm thyroid problems and any abnormality related with thyroid gland.

Self help is the best help, so start with yourself and help people around you to live a healthier life by staying aware of their health conditions.

 

Check For Thyroid Disorders
 

This post has already been read 129 times!

Leave a Reply

Your email address will not be published. Required fields are marked *