Pituitary Tumors Evaluation Flashcards
Pituitary tumors can present with endocrine hyperfunctioning or endocrine deficit due to mass effect, visual field deficits classically bitemporal hemianopia, and deficits of cranial nerves. All of the following cranial nerves can be affected by pituitary adenoma except?
● A. Cranial nerve 3
● B. Cranial nerve 4
● C. Cranial nerve 6
● D. Cranial nerves V1 and V2
● E. Cranial nerve V3
Practice guidelines for visual evaluation in patients with pituitary adenoma include evaluation by an ophthalmologist, automatic static perimetry to detect visual field deficits, visual evoked potential, and optical coherence tomography (not a practice standard). Which patients should be advised that the chances of return of vision postoperatively are reduced?
● A. Those with visual loss for more than 7 days
● B. Older patients and patients with visual loss for more than 28 days
● C. Older patients and those with visual loss for more than 4 months
● D. Older patients and those with visual loss for more than 6 months
● E. All patients with complete visual loss for more than 72 hours
Chiasma is located above the sella in most patients but it is posterior to the sella (postfixed chiasma) in 4% and anterior to the sella (prefixed chiasma) in 8% of cases. A patient with pituitary adenoma presents with monocular visual loss in one eye with superior temporal quadrantanopsia in the contralateral eye from compression of anterior knee of Wilbrand (pie in the sky defect or junctional scotoma). This finding is most common in which type of chiasma?
● A. Postfixed chiasma
● B. Prefixed chiasma
● C. Central chiasma
● D. Chiasma pushed toward one side
● E. Chiasma pushed downward
Screening tests for anterior pituitary hormones should be checked in all patients with pituitary tumors. Cortisol level generally peak between 7 and 8 a.m., and the normal level of cortisol is between 6 and 18 μg/100 mL. Following statements regarding interpretation of cortisol level are correct except?
● A. 8 a.m. cortisol level is more accurate for detecting hypocortisolism
● B. 24-hour urine-free cortisol is also accurate for detecting hypocortisolism
● C. 8 a.m. cortisol less than 6 μg/100 mL is suggestive of adrenal insufficiency
● D. 8 a.m. cortisol level between 6 and 14 μg/100 mL is non-diagnostic
● E. 8 a.m. cortisol more than 14 μg/100 mL is suggestive that adrenal insufficiency is unlikely
Selective loss of a single pituitary hormone together with thickening of pituitary stalk is strongly suggestive of which of the following?
● A. Pituitary stalk tumor
● B. Hypothalamic tumor extending to pituitary stalk
● C. Selective pituitary adenoma
● D. Autoimmune hypophysitis
● E. None of the above
Normal value of T4 hormone is 4 to 12 μg/100 mL while that of TSH is 0.4 to 5.5 mcU/100 mL. Normal response of thyrotropin releasing hormone (TRH) stimulation test (500 μg TRH IV) is peak TSH twice baseline value at 30 minutes. What does exaggerated response suggests?
● A. Secondary hypothyroidism
● B. Pituitary deficiency
● C. Primary hypothyroidism
● D. TSH secreting adenoma
● E. Hypothalamus insufficiency
Normal levels of prolactin (ng/mL) are 3–30, 10–400, and 2-20 in nonpregnant, pregnant, and postmenopausal females. Moderate elevation of 25 to 150 suggests prolactinoma or stalk effect while levels more than 150 suggests prolactinoma.
Which of the following statements regarding high prolactin level is correct?
● A. Prolactin is the only pituitary hormone primarily under inhibitory regulation
● B. Stalk effect is due to compression or injury to hypothalamus or pituitary stalk from surgery or from tumor mass
● C. Levels more than 500 usually suggests that surgery alone will not be able to normalize prolactin (PRL)
● D. Hook effect is falsely low levels of PRL in the presence of extremely high levels of PRLs due to formation of PRL antibody signal complexes
● E. All of the above
Dexamethasone 1 mg given orally at 11 p.m., measuring serum cortisol at 8 a.m., and serum sample next morning is a low-dose dexamethasone suppression test. If cortisol is less than 1.8 μg/dL, Cushing syndrome (CS) is ruled out while if cortisol is more than 10 μg/dL CS is probably present. Following tests are used to distinguish Cushing’s disease from ectopic ACTH production except?
● A. Random serum ACTH levels (if less than 5 ng/L, then ectopic ACTH less likely)
● B. Abdominal CT to see ectopic source of ACTH
● C. High-dose dexamethasone suppression test
● D. Metyrapone test
● E. Cosyntropin stimulation test
E. Cosyntropin stimulation test
What is the most useful test for a patient with acromegaly?
● A. Insulin-like growth factor (IGF-1) levels
● B. Oral glucose suppression test
● C. Growth hormone releasing hormone levels
● D. Growth hormone releasing hormone stimulation test
● E. Octreotide scan
A. Insulin-like growth factor (IGF-1) levels
Numerous criteria have been proposed to determine cavernous sinus invasion. Which of the following is correct regarding Knosp et al’s grading of cavernous sinus invasion?
● A. Grade 0: tumor does not cross medial line
● B. Grade 1: tumor crosses the medial line but not the median line
● C. Grade 2: tumor crosses the median line but not the lateral line
● D. Grade 3 (a and b): tumor extends lateral to lateral line superiorly or inferiorly
● E. Grade 4: tumor completely wraps around the intracavernous ICA
● F. All of the above correct
F. All of the above correct
A 30-year-old female presents with palpitations and excessive sweating. Which of the following suggest secondary hyperthyroidism on thyroid function tests?
● A. ↓TSH↑free T4
● B. ↓TSH ↓free T4
● C. ↑TSH ↓free T4
● D. ↑TSH ↑free T4
● E. Thyroid Usg
D. ↑TSH ↑free T4
Desaturation of color is an early sign of which of the following?
● A. Chiasmal compression
● B. Optic nerve compression
● C. Optic nerve atrophy
● D. Papilledema
● E. Ethambutol toxicity
A. Chiasmal compression
A 40-year-old male with pituitary adenoma was referred for ophthalmology consult. Which of the followings is not a screening test but may provide prognosticative information?
● A. Visual Humphrey field test
● B. Goldman field test
● C. Static visual field tests
● D. Optical coherence tomography
● E. Visual acuity
D. Optical coherence tomography
A 35-year-old female with amenorrhea presented with visual disturbance. MRI of brain revealed a 4-cm pituitary tumor. The prolactin levels were within normal range, which may be attributed to which of the following?
● A. Stalk effect
● B. Hook effect
● C. Macroprolactinemia
● D. OCP-induced
● E. Antiplatelet therapy
B. Hook effect
How high the prolactin levels can be in a pregnant female?
● A. 400
● B. 800
● C. 1000
● D. 1200
● E. 1500
A. 400
