Case Review Questions Flashcards
What are the diagnostic criteria for NF-2?
- Bilateral vestibular schwannoma.
- Family history of NF-2 (first degree relative) plus unilateral VS.
- Family history of NF-2 plus two of the following: meningioma, schwannoma (nonvestibular), glioma, neurofibroma, juvenile posterior subcapsular lenticular cataract, or opacity.
What is the 50/50 rule for serviceable hearing?
- A pure tone (PTA) showing values of < 50 dB and speech discrimination with recognition of > 50% indicate serviceable hearing.
Differential diagnosis for intraventricular lesions?
CENTRAL MS
- Choroid plexus papilloma or carcinoma, colloid cyst, central neurocytoma, cavernoma.
- Ependymoma, epidermoid/dermoid.
- Neurocytoma.
- Teratoma, tuber.
- “Rule out” infection.
- Astrocytoma, AVM, aneurysm, abscess.
- Lipoma, lymphoma.
- Mets, meningioma.
- Subependymoma, SEGA.
Which neurocutaneous syndrome is associated with SEGAs?
- Tuberous sclerosis.
What are some complications that can be seen with transcallosal approaches to the lateral ventricles?
- Weakness.
- Akinetic mutism.
- Memory deficits.
Which vein does the thalamostriate vein empty into?
- Internal cerebral vein.
What are some findings associated with Sturge-Weber?
- Port wine stain (usually affecting V1).
- Leptomeningeal angiomas.
- Seizures.
- Hemiparesis.
- MR or learning disability.
- Glaucoma.
What are some indications for hemispherectomy?
- Intractable epilepsy with unilateral hemisphere damage.
- Congenital hemiplegia.
- Chronic encephalitis.
- Hemimegalencephaly.
- Sturge-Weber syndrome.
What lab abnormality can be seen with hemangioblastomas?
- Polycythemia.
Genetic mutation seen in NF-1?
- NF1 gene mutation on chrom. 17.
Genetic mutation seen in NF-2?
- NF2 gene mutation on chrom. 22.
Genetic mutation seen in tuberous sclerosis?
- TSC1 and TSC2 gene mutations on chrom. 9 and 16.
Genetic mutation seen in VHL?
- VHL gene mutation on chrom. 3P.
What are the 3 main types of spinal AVMs?
- Dural AV fistula.
- Perimedullary fistula.
- Intramedullary AVMs.
Pathophysiology of dural AV fistulas.
- Lesion consists of a small AV fistula within or just beneath the dura at the point where a feeding radicular artery enters the dura at the nerve root sleeve.
How do dural AV fistulas cause neurologic deficits?
- AV fistulas are low flow lesions resulting in venous hypertension and decreased spinal cord perfusion.
Pathophysiology of perimedullary fistulas.
- Located intradurally but in the extramedullary space.
2. Characterized by a single shunt without a nidus.
Indications to operate on GSWs to the head?
- Favorable GCS.
- Debridement of devitalized tissue or bone fragments.
- Evacuation of hematomas.
- Separation of intracranial component from air sinuses.
Contraindications for surgery in GSWs to the head?
- Bullet traveling across the midline.
- Bullet traveling across ventricles.
- Bullets traveling across more than one contiguous lobe of the brain.
Symptoms of Foster-Kennedy syndrome.
- Anosmia.
- Unilateral optic atrophy.
- Contralateral papilledema.
What are the main features distinguishing olfactory groove meningiomas from tuberculum sellae meningiomas.
- The location of the chiasm.
- The optic nerves and optic chiasm are located inferolateral to the tumor with olfactory groove meningiomas.
- The optic nerves and chiasm are located superolateral to the tumor in tuberculum sellae meningiomas.
Describe Chiari type 1.
- Shallow posterior fossa.
- Tonsillar descent down to the level of C1-C2 junction.
- Posterior compression of the cervical spinal cord.
Describe Chiari type 2.
- Shallow posterior fossa.
- Descent of the cerebellar hemispheres, vermis and tonsils to the upper cervical spinal cord.
- Posterior compression of the brainstem and cervical spinal cord.
Describe Chiari type 3.
- Shallow posterior fossa.
- Tonsillar herniation.
- Brainstem and cervical spinal cord compression.
- Occipital encephalocele.
Location and function of the principal sensory nucleus of CN V.
- Located in the upper pons.
2. Conveys tactile and pressure senses from the face.
Location and function of the mesencephalic nucleus of CN V.
- Located near the central gray matter of the upper 4th ventricle.
- Conveys pressure and kinesthetic senses from the teeth, hard palate, and jaw.
Location and function of the spinal trigeminal nucleus of CN V.
- Extends from the upper cervical spine to the midpons.
- Divided into 3 parts (pars caudalis, pars interpolaris, and pars oralis) which convey sensation of pain and temperature from different parts of the face.
Function of the motor nucleus of CN V.
- Relays fibers to the muscles of mastication and plays part in the jaw jerk reflex.
Which vessel is the most common culprit of in trigeminal neuralgia?
- Superior cerebellar artery.
What is the definition of moyamoya disease?
- Progressive occlusion of terminal ICAs, ACAs or MCAs.
2. Profuse lenticulostriate collateral formation (moyamoya vessels) at the base of the brain.
Clinical presentations of moyamoya in children?
- Ischemic symptoms in 80%.
- Epilepsy in 5%.
- ICH in 2.5%.
- Other symptoms in 12.5% (headache, movement disorders, or mix of symptoms).
What are some factors associated with moyamoya?
- Asian ethnicity.
- NF-1.
- Radiation for optic or hypothalamic pathway gliomas.
- Down syndrome.
- Renal artery stenosis.
- Thalassemia and sickle cell anemia.
Direct revascularization procedures for moyamoya?
- Superficial temporal artery to MCA bypass.
Indirect revascularization procedures for moyamoya?
- EDAS: encephaloduroarterosynagniosis.
- EMS: encephalomyosynangiosis.
- EDAMS: encephaloduraarteriomyosynangiosis.
- Modified EDAS (pial synangiosis).
Why are vagal nerve stimulators contraindicated ont he right vagal nerve?
- The right vagal nerve innervates the SA node in more than 60% and stimulation will result in asystole.
What are common side effects of vagal nerve stimulators?
- Cough.
- Hoarseness.
- Throat pain.
