Chpt 7 Clinicals Flashcards
Congenital Dermal Sinus
1) Development defect associated with:
- closure of the neural tube
- formation of the meninges in the lumbosacral area
2) Aka Dermal Sinus
3) Caused by a failure of the ectoderm (future skin) to completely separate from:
- neuroectoderm
- primitive meninges
4) sometimes discovered in patients who have recurrent, but unexplained bouts w/meningities
Dura Mater
1) aka pachymeninx
2) composed of elongated fibroblasts and alot of collagen fibrils
3) Contains: BV, Nerves
4) Divid into
- outer (periosteal/endosteal)
- inner (meningeal)
- Border cell portions
5) No distinct border between periosteal and meningeal portions of the dura
6) Fibroblasts of Periosteal Dura
- larger
- less elongated
7) Fibroblasts of the Meningeal Dura
- more flattened and elongated
- smaller nuclei
- cytoplasm darker
Compartments and Herniation Syndromes
1) Supratentorial Compartment
- located superior to the tentorium cerebelli
- R and L half separated by falx cerebri
2) infratentorial compartment
- located inferior to tentorium cerebelli
- only one
Herniation Syndromes
1) Occur when there is an intracranial event that causes increase in ICP
- hemorrhage
- rapid tumor growth
- traumatic brain injury
2) Forces the Brain over the edge of the dural reflection
Cingulate Herniation
1) Aka subfalcine herniation
2) Supratentorial Herniation
3) lesion in one cerebral hemisphere expands toward midline
- deform falx cerebri
- force the cingulate gyrus under the edge of the falx into opposite hemisphere
4) Deficits:
- occlusion of the adjacent anterior cerebral artery
Central Herniation
1) AKA transtentorial Herniation
2) diencephalon is forced downward through the tectorial incisure or notch
3) Neurological emergency
- 90% serious disability or death
Uncal Herniation
1) Rapid expanding lesion
- usually hematoma
2) Forces the uncus over the edge of the tentorium cerebelli
3) damage to midbrain
4) most common deficits
- decreased level of consciousness
- dilation of the pupil and loss of most eye movement reflecting damage to the ipsilateral oculomotor nerve
- contralateral hemiplegia
Examples of Herniation syndromes related to the supratentorial compartment:
1) Cingulate herniation
2) Central herniation
3) Uncal Herniation
Examples of hernaiton syndromes related to infratentorial compartment:
1) Upward cerebellar herniation
2) Tonsilar Herniation
Upward Cerebellar herniation
1) mass or pressure increase in the posterior cranial fossa
-forces the cerebellum up through the tentorial incisor
=damage to midbrain
Tonsillar Herniation
1) Tonsils of cerebellum are forced downward into/through foramen magnum
2) resulting pressure on medulla
- damage respiratory centers
3) result in sudden death
