Extramural and Intramural glands

Hi again!

Now that I have had some nutrition, I will have a shot at your Q.

My first observation would be that, in general, try and look at medical terminology from the viewpoint of its component syllables and their Greek/Latin roots, as well as examine other similar words to work out the meaning, and the logic behind it.

I am sure you are aware that "intra-" means inside or within, and "extra-" = outside; "mural" refers to something to do with a wall e.g. taking cardiology for a moment, there is a clear distinction between sub-endocardial ischaemia [ONLY below the endocardium] and transmural ischaemia [spanning the entire myocardial wall - "trans" means across as in trans-Atlantic flights][the ECG appearances are also different - you are welcome to ask me when you do your cardiology firm]. Another example is aortic intramural haemorrhage [IMH], which needs to be distinguished from aortic dissection. IMH involves blood within a split in the arterial tunica media.

Having looked at the origins and examples of these terms, you might already be predicting that intramural "glands" are those within a wall [in your example, the biliary ductal wall], whereas extradural glands are those completely outside such a conduit.

If you need further detail or more examples, do feel free to PM me.

Thanks!
M

Hi again,
"DUCT from gland linked externally from hollow organ"

Taking one of your own examples, namely the submandibular salivary gland, it has a link to the hollow organ [the] from outside this cavity [externally] i.e. from the digastric triangle [where the gland is located]; the link is via the the 5 cm long submandibular DUCT, which opens into the mouth near the frenulum of the tongue.

Incidentally, in your examples [below the bold text in your last post [the one to which I am now replying]], "gallbladder" is strictly speaking incorrect, as it IS NOT A GLAND [it simply STORES bile secreted by the liver].

Hope this helps!
M