Very small thyroid?

I'm here in Spain so sometimes the language is a problem when seeing hospital consultants.
I have had an underactive thyroid since 1994, treated by the standard thyroid replacement drugs.
At the end of 2006 I was taking 50mg on one day and 75mg the next etc. All seemed OK with the b/t results TSH 2.18, T4 1.09 but another consultant told me to take 75mg every day adding that it was easier for me!
The next appointment was withI my usual consultant who was shocked at the test results TSH <0.1, T4 1.37 Triyodtironia 2.6 and wanted to know why my medication had been changed?
He told me to just take 50mg per day and so the following 6 month b/t results were TSH 4.7, T4 1.00. This time he ordered an ecoscan of the thyroid. I have these about every 2 years and all has been fine.
Yesterday I had the ecoscan and was told by the technician that I had a 'very small' thyroid.
I don't see the consultant for these results and the last b/t results until mid July and it has left me wondering what this term means?? Is it significant and is it anything to be concerned about?  


This discussion is related to a small thyroid gland.

[898]

The nomal volume range is between 8 and 18 cubic centimeters.

[Janet507]

Sorry but I don't understand you answer. Maybe the measurements here in Spain are different to what you are referring to...don't know and I'm no expert on thyroid which is why I came here to ask my question. Can I help you with further information?

[898]

What did the ultrasound say about your  thyroid size in sentimeters?

[Janet507]

Ah I see what you mean now...well, he didn't give me that information, just said that it looked very small. I just wanted to know, what is the significance of a very small thyroid?

[898]

One of the possibilities can be the reaction to the prolonged use of thyroid hormone replacemant drugs; sometimes they are causing thyroid to decrease in size and in activity (as it is not need to produce that much hormones due to external homone source). the thyroid gland has ability to change its size up to 2 times from "mean " 13 cubic centimeters based in order to adjust to the hormone demand or in reaction to the iodine level in diet.
In some cases if hypothyroidism is due to the pitiuary problems (low TSH and T4 levels at the same time) [secondary  hypo-], the thyroid is also has a small size.

[Janet507]

Thanks once again....well of course I don't know if either of these are the answer to the small thyroid. But supposing it were due to prolonged us of thyroid meds...what would happen then?
Or what if it's a pituary gland problem...how might that be treated?
Thanks again.