Hello and welcome to the Zero to Finals podcast. My name is Tom and in this episode I'm going to be talking you through Acromegaly.

Now if you want to find written notes on this topic, you can follow along at zero tofinals.com

slash acromegaly or in the endocrinology section of the Zero to Finals Medicine book. So let's get straight into it. Acromegaly or in the endocrinology section of the zero definals medicine book so let's get straight into it

acromegaly is the clinical manifestation of excessive growth hormone or gh a growth hormone is produced by the anterior

pituitary gland the most common cause of unregulated growth hormone is a pituitary adenoma,

so a hormone secreting tumour of that pituitary gland. And this adenoma might be microscopic,

so small that you can't see it on a scan, or it can be significantly sized so that it causes

compression of the local structures.

Rarely acromegaly can also be secondary to a cancer, like a lung or a pancreatic cancer,

that secretes either ectopic growth hormone releasing hormone, or GHRH, or ectopic growth hormone itself.

There's a structure called the optic chiasm, and this sits just above the pituitary gland.

And what this optic chiasm is is the point where the optic nerves coming from the eyes cross over to different sides of the head

and enter into the occipital lobe, which interprets those visual signals.

And a protrity tumour that has significant size

will start to press on this structure called the optic chiasm.

And pressure on the optic chasm will lead to a stereoty a stereotypical bitemporal hemianopia visual field defect.

So what this is is basically a loss of vision of both of the outer halves of the eyes

because as the visual signals from the optic nerve come through the optic chasm, the signals that sense the

outer part of the visual field cross over in the middle, and it's this middle part that is

pressed on by the tumour, and this causes loss of vision of the outer sides of the eyes, which we

call bi-temporal hemianopia. So how does acromegaly present?

If there's a space-occupying lesion or a significant-sized tumour, you might find somebody with headaches

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