Hello and welcome to the Zero to Finals podcast.

My name is Tom and in this episode I'm going to be talking to you about Acromegaly.

Then you can find written notes on this topic at zero to finals.com slash acromegaly

or in the endocrinology section of the zero to finals medicine book. So let's get straight

into it. Acromegaly is the result of excessive growth hormone. Let's talk about the pathophysiology.

Growth hormone is produced by the anterior pituitary gland. The most common cause of unregulated growth hormone

secretion is a pituitary adenoma. This adenoma can be microscopic or a significantly sized

tumour that causes compression of local structures. Very rarely, acromegaly can be

secondary to cancer, such as lung or pancreatic cancer, where the tumor is secreting

ectopic growth hormone releasing hormone, or GHRH, or directly releasing growth hormone. This is a paroneoplastic syndrome,

meaning that it occurs alongside, which is what paramines, the neoplasm, which is the tumour.

The optic chasm sits just above the pituitary gland.

The optic chiasm is the point where the optic nerves coming from the eyes

cross over to the opposite side of the head.

A pituitary tumour of sufficient size can press on the optic chiasm.

Pressure on the optic chasm leads to a stereotypical

bipemporal hemianopia visual field defect. A bitemporal hemianopia describes the loss of vision of the

outer half of both eyes. The inner half of the vision is spared as this does not cross over at the

optic chiasm and it stays on the same side of the head as it travels from the eyes to the visual cortex in

the occipital lobe at the back of the brain. Let's talk about the presentation of acromegaly. A space occupying large pituitary

tumour can cause headaches and a visual field defect, specifically bi-temporal hemianopia.

Excessive growth hormone causes tissue growth, resulting in a prominent forehead and prominent brow,

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