Sunday 26 May 2019

Acromegaly - Points to be noted by an Ophthalmologist

A 40-year-old patient has noticed that his feet became bigger beyond his usual shoes...what do you think the causes for such condition?
the next Qs are about the main endocrinal cause for this condition? 

*Causes of enlarged foot:
  1. Endocrine: Acromegaly- may be hypothyroidism(weight gain)
  2. Oedema (e.g. pitting: cardiac failure- non- pitting: lymphedema)

*Acidophil tumors cause gigantism in children and acromegaly in adults. Acromegaly is caused by excessive growth hormone (GH) occurring during adult life, after epiphyseal closure and is almost invariably due to a secreting pituitary acidophil adenoma.
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N.B: Be aware of the following;
  1. Bitemporal hemianopia is due to chiasmal compression.
Correction: bitemporal hemianopia is due to multiple causes, one of them is chiasmal compression.


  1. Chiasmal compression is due pituitary adenoma
Correction: there are many causes for chiasmal compression. Pituitary causes are one of them.


  1. Chiasmal compression result in bitemporal hemianopia
Correction: chiasmal compression leads to different visual field defects . Bitemporal hemianopia is one of them.


  1. Pituitary adenoma result in chiasmal compression.
Correction: it varies depend on the position of chiasm (central- pre- post fixed).


  1. Pituitary adenoma is prolactinoma.
Correction: there are different types of adenoma with different manifestations.
Q: What are signs?

  • Age: 4th–5th decades

  • Enlargement: the head, jaw “mandible” (dental malocclusion), hands, feet, tongue and internal organs.

  • Face: Coarseness of features (thick lips, exaggerated nasolabial folds, prominent supraorbital ridges).



  • Skin:
Hyperhidrosis, and hirsutism in females.
seborrhoea, acne

  • Complications:
osteoarthritis, carpal tunnel syndrome, neuropathy
gonadal dysfunction
cardiomyopathy, hypertension,
respiratory disease,
diabetes mellitus,


Q: What are the investigations?

The diagnosis may be confirmed by:
  1. Direct: Measuring GH levels in response to an oral glucose tolerance test. Normal individuals manifest suppression of GH levels to below 2mU/L. However, in acromegaly, GH levels do not fall, and may paradoxically rise.

  1. Indirect: increased IGF-1(insulin growth factor).

Q: What are the ophthalmic features of acromegaly?

  • Bitemporal hemianopia and optic atrophy
  • Angioid streaks
  • see-saw nystagmus of Maddox



Q: What are the treatment options?


  • Medical: Octreotide (Octreotide is similar to somatostatin. Somatostain is the natural antagonist of growth hormone. So, this octreotide inhibits the secretion of GH).
N.B: Octreotide is a vasoconstrictor which is used also in GI bleeding.


  • Radiotherapy (external beam or by implantation of yttrium rods in the pituitary).


  • Surgical: trans-sphenoidal hypophysectomy






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