Anatomy and Blood Supply
A 45-year-old man presents with progressive headaches and difficulty seeing objects approaching from either side while driving. MRI shows a pituitary macroadenoma extending superiorly. The tumor is compressing this structure.
What is the optic chiasm?
A patient with Addison disease has elevated ACTH levels due to loss of cortisol feedback. ACTH normally stimulates cortisol release from this organ.
What is the adrenal cortex?
A patient taking long-term corticosteroids develops suppression of endogenous ACTH production due to this physiologic process.
What is negative feedback inhibition?
Following transsphenoidal surgery, a patient develops intense thirst and produces 8 liters of dilute urine daily. The diagnosis is:
What is central diabetes insipidus?
A pituitary tumor is removed through the nasal cavity and sphenoid sinus using this surgical approach.
What is the transsphenoidal approach?
During neurosurgery, the surgeon accidentally damages the vascular connection carrying hypothalamic releasing hormones to the anterior pituitary. This blood vessel network is called:
What is the hypophyseal portal system?
A woman presents with galactorrhea after starting an antipsychotic medication that blocks dopamine receptors. Blocking dopamine increases secretion of this hormone.
What is prolactin?
A child with growth failure is found to have deficiency of the hypothalamic hormone that stimulates growth hormone release. This hormone is:
What is GHRH?
A woman presents with amenorrhea, galactorrhea, headaches, and bitemporal hemianopia. The most likely diagnosis is:
What is prolactinoma?
Following pituitary surgery, a patient cannot conserve water and develops hypernatremia. Damage to this pituitary region is most likely responsible.
What is the posterior pituitary?
A lesion affecting the hypothalamus disrupts ADH production. The two nuclei most likely involved are these.
What are the supraoptic and paraventricular nuclei?
A new mother can produce milk normally but cannot eject it during breastfeeding after a complicated delivery. Deficiency of this hormone is most likely responsible.
What is oxytocin?
A patient with primary hypothyroidism has low T3/T4 but elevated TSH because the pituitary is responding to loss of this mechanism.
What is negative feedback?
A patient has moon facies, central obesity, purple striae, and hypertension. Labs reveal elevated ACTH from a pituitary adenoma. The diagnosis is:
What is Cushing disease?
Compression of the optic chiasm by a pituitary macroadenoma causes this characteristic visual deficit.
What is bitemporal hemianopia?
A patient develops hyperprolactinemia after traumatic brain injury damages the connection between the hypothalamus and pituitary. The damaged structure is this.
What is the pituitary stalk (infundibulum)?
A patient develops severe dehydration, hypernatremia, and excessive urination following pituitary surgery. Deficiency of this hormone is most likely responsible.
What is ADH (vasopressin)?
A patient with pituitary stalk compression develops elevated prolactin because hypothalamic delivery of this inhibitory neurotransmitter is reduced.
What is dopamine?
A postpartum woman develops fatigue, inability to lactate, and amenorrhea after massive hemorrhage during childbirth. The diagnosis is:
What is Sheehan syndrome?
A patient develops hyperprolactinemia after pituitary stalk transection because this inhibitory factor can no longer reach the anterior pituitary.
What is dopamine?
A pituitary adenoma causes ischemia of the anterior pituitary after compression of the arterial supply feeding the portal circulation. The affected artery is this.
What is the superior hypophyseal artery?
A patient with primary hypothyroidism has elevated prolactin due to increased secretion of this hypothalamic hormone.
What is TRH?
Lab tests show elevated cortisol and suppressed ACTH. Imaging most likely reveals a cortisol-secreting tumor in this organ.
What is the adrenal gland?
A man presents with enlarged hands, coarse facial features, hypertension, and elevated IGF-1. The underlying pituitary disorder is:
What is acromegaly?
After pituitary surgery, a patient develops fatigue, hypotension, and hypoglycemia due to loss of ACTH secretion causing secondary deficiency of this hormone. .
What is cortisol?