Hydrocephalus and Spina Bifida Flashcards
Explain hydrocephalus incl classifications
Occurs when there is an imbalance between the production and absorption of CSF. Can be classified based on:
- type (obstructive: flow of CSF is blocked or communicating: absorption of CSF is disrupted or overproduced)
- aetiology (congenital or acquired, eg acquired via Spina bifida)
- co-morbidities (present or absent)
What is the neuropathology of hydrocephalus
- Axonal destruction and white matter atrophy (more so than cortical areas)
- Disruption to myelination
- Thinning and stretching of the callosal and projection fibres
- Atrophy of the olfactory nerves and optic track
What is the treatment for hydrocephalus, incl best predictor of outcomes
- Insertion of a shunt via a burr hole through the skull and into the ventricle
- Accumulated CSF drains through the shunt into the extra-cranial body cavity, usually the stomach.
- Best predictor of outcomes is the time period of increased cranial pressure, not so much the size of enlarged ventricles
- 40% of shunts malfunction and may give rise to cognitive changes, decline in functioning, persistent headaches, vomiting, and lowered arousal. If untreated, can lead to acute illness and coma
What is Arnold Chiari Malformation?
- It is malformation of the brain stem and cerebellum that is commonly associated with hydrocephalus.
- Structures are displaced into the spinal canal and can obstruct flow of CSF and cause hydrocephalus
What is spina bifida incl risk factors
- A defect of neural tube closure in early embryogenesis, occurring around the first month of gestation in the neurolation phase.
- It manifests as malformation along any point of the spinal cord between the cervical and lower sacral regions
- Lack of folic acid during pregnancy is a risk factor
What are the different forms of SB?
- Spina bifida occulta (mildest form)
- Spina bifida cystica with two forms: meningocele and myelomeningocele (most severe form)
Describe SB occulta
- usually asymptomatic
- vertebral arches are incomplete but the CNS develops normally
- may be apparent due to abnormalities in skin tissue at the site of malformation
Describe SB Meningocele
- protrusion of the meninges and CSF through abnormal vertebral arches
- this protrusion forms a skin covered sac, usually in the region of the lumbosacral spine
- CNS is otherwise intact
Describe SB Myelomeningocele
- most common and severe form of SB
- At birth, appears as on open cyst on the back
- The sac contains damaged spinal cord and nerves, with the level of lesion related to severity of impairments
90% of children with SB myelomeningocele will have:
- hydrocephalus
- Arnold chiari malformation
- lower limb paralysis
- bowel and bladder incontinence
What are some cognitive areas effected in SB myelomeningocele?
- attention
- language
- memory
- visuoperception and motor integration
- exec
Describe the attention issues seen in SB myelomeningocele
- poor sustained attention
- difficulties with selective/focused attention
- reduced arousal, motivation, and initiation
Describe the language deficits seen in SB myelomeningocele
- vocab is usually fine, disorder of higher level language rather than content
- deficits in fluency, comprehension, and inferential language
- poor monitoring of logic, relevance or appropriateness
- slow and reduced comprehension
Describe the memory and new learning deficits in SB myelomeningocele
- difficulties with encoding, rate of learning, delayed recall, and spontaneous retrieval
- recognition and cued recall stronger
- struggle with learning abstract concepts (eg mathematics)
Describe the visuo-perceptual and motor deficits in SB myelomeningocele
- poor at interpreting visuospatial information
- impaired fine motor skills/clumsiness
- slow and untidy handwriting
