Spina bifida Flashcards
What are the categories of spina bifida
Occulta (covered with skin, looks normal, etc.) and aperta (open)
What is the destiny of the epiblast?
In first few weeks it is growing rapidly forming the neural crests. It is programmed to all become neurons. The crests become the neural tube
More formal term for “neural tube defects”
Dysraphism
Timeline of normal brain and spinal cord development
Brain and spinal cord 3-8 weeks. Primary neurulation 3-4 weeks
How does spina bifida happen?
The two crests don’t meet and close so left open (at head = anencephaly or at “tail” then spina bifida). Or if things get into the neural tube before it closes or if it is still connected to epiblast, also forms spina bifida.
Spina bifida occulta
Usually excluded from discussion and often not seen publicly.
Meningocele.
Skin covered pouching of dura through unfused bone. All the nervous tissue is inside still. 10% as common as myelomeningocele
Myelomeningocele
Neural tissues protrudes out in sac, maybe slight membrane covering.
When does the neural tube develop defects like spina bifida?
During the first couple weeks, complete around week 4.
Dermal sinus tract
Epithelial lined tract from failed segmental dysjunction. Associated with epidermoids, dermoids. Present due to recurrent infections or tethered spinal cord. Associated with skin dimples, hyperpigmentation, hairy nevi, and capillary malformations
Dangerous dimples
Any above your belt; If it is going upwards; drainage is problem; repeated meningitis; too much hair; lipoma; weird vasculature
Cutaneous lesions and concerns
Common, about 5% in kids. Concern on large ones (>3-5mm) that are higher on back and other previously mentioned features. Can be orthopaedic manifestations (scoliosis, etc)
Scolosis
Caused be syrinx (fluid buildup in spinal cord) or tethering of spinal cord, atypical features include left curve (R curve normal in girls), curve in boys, or more extreme angles). Can lead to club foot, limb length differences, etc
Tethering of the spinal cord
ie pulling on spinal cord due to the fluid buildup or even scarring. Can cause problems but some are reversible (esp w/ scarring).
Urologic anomalies and management
Urgency (more when older), hyperactive bladder, frequent UTIs. Management unclear, some show recovery if managed early but others never will.
Epidemiology of neural tube defects
Common esp. because 50% of pregnancies are unplanned. Preventable with folate intake
Multifactorial inheritance of neural tube defects
Some children with Trisomy 13 or 18 have neural cord defects. There are some genetic and environmental factors.
Disability in neural tube defects.
Depends on the height of the defect. The higher the worse it is as everything below is impacted, ie a thoracic myelomeningocele would affect continence, dislocated hips, paralysis, etc.; L4 can walk with difficulty, still incontinent, easier in wheelchair (often lose walking when put on weight). It can pull on brain (before skull formed) which has major problems, like not being able to breathe or swallow. Neuro-cognitive also a problem.
Social problems with neural tube defects
For those in wheelchairs or non-walking, they have difficulty with socialization. Best to keep them walking as long as possible if they can when they are born. Incontinence is also a major concern.
Pre-natal care of neural tube defect
You can see the “cyst” building up on prenatal MRI. Can’t really tell if meningocele or myelomenigocele, so have conversation.
Post-natal care
Baby born with sac, cover with saran wrap, then close back within 48 hours
Other findings with neural tube defects
Chiari malformation (II) (cerebellum tugged into foramen magnum), hydrocephalus, beaking of tectum (midbrain)
Multidisciplinary management
Dentists: Need to be aware of pressure and patience of child. Many have bad oral health in general (lower priority for parent, less development of jaw if fed through G tube, improper development, risk of choking if swallowing not good). Other medical specialists watching for scoliosis, continence function, and continued observation. Social workers, group home staff.
