Chiasmal Syndrome (F) Flashcards
What kind of atrophy is seen in patients with bitemporal hemianopias from chiasmal compression of crossing nasal fibers?
transverse “band” optic atrophy
What arises from the retention and accumulation of mucoid secretions within the sinus, which eventually gives rise to expansion, thinning and distention or actual destruction of the wall?
sinus mucocele
What are the impacts of hypersecreting pituitary?
- hyperprolactinemia
- growth hormone excess
- ACTH excess (Cushings)
- hyperthyroidism
- excess LH/FSH
How do you treat a pituitary abscess from a mucocele?
transsphenoidal drainage of abscess and antibiotics
What are the possible symptoms of pituitary apoplexy?
- severe headache
- vomiting
- double vision (unilateral or bilateral ophthalmoplegia)
- loss of vision
- significant disturbances of consciousness
- hemiparesis, ocular motor palsy, VF defects
- ptosis
- loss of sensation in forehead
Is the bitemporal hemianopia related to pituitary adenoma even, more dense superiorly, or inferiorly? 1. Why? 2
- more dense loss superiorly
2. adenoma pushing on inferior fibers
How common are aneurysms that cause chiasmal syndrome? 1. What are the possible locations of aneurysm? 2
- rare
2. internal carotid, carotid-ophthalmic, anterior communicating, cavernous
What is 80% of the populations optic chiasms positioned over? 1. What is 9% of them placed over (associated VF defect if impacted)? 2. What is 11% of them placed over (associated VF defect if impacted)? 3
- pituitary gland
- tuberculum sellae, aka prefixed (homonymous hemianopia)
- dorsum sellae, aka postfixed (nerve fiber bundle defect)
What are the most common causes of chiasmal syndrome?
- pituitary adenoma
- craniopharyngioma
- meningioma
- glioma
What is the management for chiasmal syndrome?
- urgent MRI of brain with contrast
2. referral to endocrinology if appropriate
What are the areas that can have meningiomas of the skull base that can affect the chiasm?
- tuberculum sellae
- diaphragma sellae
- anterior clinoid processes
What are the treatment options for a pituitary adenoma (and situation it is best in)?
- transsphenoidal surgery (nonfunctioning tumors)
- radiation therapy (recurrent or residual tumors)
- medical therapy (prolactin secreting tumors)
What signs of chiasmal syndrome may be noticed on testing?
- may skip last letter on VA (temporal loss)
2. only say one number on Ishihara (temporal)
Where are the cells involved in a craniopharyngioma from? 1. What age does this typically occur? 2. What is usual outcome? 3
- nests of squamous epithelial cells (remnants of Rathke’s pouch, which gives rise to anterior pituitary)
- first two decades of life
- generally benign but can be invasive and recurrent
What are the ways the slowly progressive, painless visual loss can present with chiasmal syndrome?
- incidental (fail VF w/ no complaints)
- slowly progressive VF or VA loss
- acute
