100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Previously searched by you
Previously searched by you
logo
USMLE STEP 1 Neurology Questions And Answers With Verified Updates $7.99
Add to cart
Quickly navigate to
Preview
  2.  
  3. USMLE STEP 1 Neurology
  4.  
  5. USMLE STEP 1 Neurology

Exam (elaborations)

USMLE STEP 1 Neurology Questions And Answers With Verified Updates
 0 purchase
  • Course
  • USMLE STEP 1 Neurology
  • Institution
  • USMLE STEP 1 Neurology

Propofol - Used for sedation in the ICU, rapid anesthesia induction, short procedures LESS POST-OPERATIVE NAUSEA than thiopental Potentiates GABAA Holoprosencephaly - Failure of LEFT AND RIGHT HEMISPHERES TO SEPARATE Usually occurs during the 5th and 6th week May be related to mutations in the...

[Show more]

Preview 4 out of 86  pages

Document information

  • August 17, 2024
  • 86
  • 2024/2025
  • Exam (elaborations)
  • Questions & answers

Subjects

Written for

  • USMLE STEP 1 Neurology
  • USMLE STEP 1 Neurology

Seller

avatar-seller
ACADEMICMATERIALS

Reviews received

Content preview

USMLE STEP 1 Neurology
Propofol - Used for sedation in the ICU, rapid anesthesia induction, short procedures

LESS POST-OPERATIVE NAUSEA than thiopental

Potentiates GABAA



Holoprosencephaly - Failure of LEFT AND RIGHT HEMISPHERES TO SEPARATE

Usually occurs during the 5th and 6th week

May be related to mutations in the SONIC HEDGEHOG signaling pathway

Moderate form = Cleft lip/palate

Severe form = Cyclopia

Seen in:

1. PATAU SYNDROME

2. FETAL ALCOHOL SYNDROME




Neural plate then gives rise to? - Neural tube and neural crest cells



Notochord becomes what? - Nucleus pulposus of the intervertebral disks in adults



Alar Plate - Dorsal [Sensory]

Same orientation as spinal cord



Basal Plate - Ventral [Motor]

Same orientation as the spinal cord



How does FGF affect chordin and noggin? - FGF regulates chordin and noggin to down regulate
BMP which leads to neural plate induction

,Three Primary Vesicles - 1. Forebrain [Prosencephalon]

2. Midbrain [Mesencephalon]

3. Hindbrain [Rhombencphaln]



The Forebrain gives rise to: - 1. Telencephalon [Cerebral hemispheres, lateral ventricles]

2. Diencephalon [Thalamus, Third Ventricle]



The Midbrain gives rise to: - 1. Mesencephalon [Midbrain, aqueduct]



The Hindbrain gives rise to: - 1. Metencephalon [Pons, cerebellum, upper part of the fourth
ventricle]

2. Myelencephalon [Medulla, Lower part of the fourth ventricle]



CNS/PNS Origins - Neuroectoderm = CNS neurons, ependymal cell [Inner lining of ventricles,
makes CSF], oligodendrocytes, astrocytes

Neural crest cells = PNS, schwann cells

Mesoderm = Microglia [Like Macrophages, originate from Mesoderm]



Neural tube defects - NEUROPORES fail to fuse [4th week] → Persistent connection between
amniotic cavity and spinal canal

Associated with:

1. Low folate levels before conception and during pregnancy

2. ↑ a-fetoprotein levels [AFP] in amniotic and maternal serum

3. ↑ AChE in amniotic fluid [Helpful confirmatory test]

-- Fetal AChe in CSF transudates across defect into amniotic fluid



Spina bifida occulta - Failure of bony spinal canal to close, NO STRUCTURAL HERNIATION

Usually seen at lower vertebral levels

,DURA INTACT

Associated w/ tuft of hair or skin dimple at level of bony defect

NORMAL AFP



Meningocele - Meninges [BUT NO NEURAL TISSUES] herniates through bony defect



Meningomyelocele - Meninges and neural tissue herniate through bony defect

Associated w/ Arnold-Chiari Type II Malformation



Anencephaly - Malformation of the ANTERIOR NEURAL TUBE →

1. No forebrain

2. Open calvarium

Clinical Findings:

1. ↑ a-fetoprotein levels [AFP]

2. Polyhydramnios [No swallowing center in brain]

3. Associated w/ MATERNAL TYPE I DIABETES

4. Maternal folate supplementation ↓ risk




Chiari Type II Malformation - Posterior fossa malformation

Significant HERNIATION of the CEREBELLAR TONSILS and VERMIS through FORAMEN MAGNUM with
AQUEDUCTAL STENOSIS and HYDROCEPHALUS

Patients often present w/:

1. Lumbosacral meningomyelocele

2. Paralysis below the defect



Dandy-Walker Malformation - AGENESIS of CEREBELLAR VERMIS with CYSTIC ENLARGEMENT of
the 4th ventricle

Fills enlarged posterior fossa

, Associated w/:

1. Hydrocephalus

2. Spina bifida



Syringomyelia - Cystic cavity [Syrinx] within SPINAL CORD

If central canal = Hydromyelia

Crossing anterior spinal commissural fibers are typically damaged

CAPE-LIKE BILATERAL LOSS OF PAIN and TEMPERATURE in the UPPER EXTREMITIES

Fine touch sensation is preserved

Associated w/:

1. Arnold Chiari malformation

2. Trauma

3. Tumor

Most common C8-T1 [CERVICAL ENLARGEMENT]



Arnold Chiari Type I Malformation - CEREBELLAR TONSILLAR ECTOPIA > 3-5 mm

Congenital

Usually asymptomatic in childhood

Manifests w/ HEADACHE and CEREBELLAR SYMPTOMS



Which arches form the anterior 2/3rds of the tongue - 1st and 2nd brachial arches

-- Sensation via CN V

-- Taste via CN VII



Which arches form the posterior 1/3rd of the tongue - 3rd and 4th brachial arches

--Sensation and taste via CN IX

-- Extreme posterior vagus

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller ACADEMICMATERIALS. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $7.99. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

69052 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 15 years now

Start selling
$7.99
  • (0)
Add to cart
Added