CC Jan 2012 Delayed fontanelle closure

echoecho's version from 2013-04-16 13:14


Question Answer
2 major fontanelles are?anterior and posterior
Which of the two fontanelles is smaller?posterior
The posterior fontanelle closes at what month of age?3-6 months of age
When does the anterior fontanelle close?it varies (38% close at 12 onths and 96% close at 24 months) so the median closure is 13.8 months
** In children with true delayed closure of the anterior fontanelle, what needs to be ruled out?certain disease states
Failure of the anterior fontanelle to close can be due to one of four major categories of pathology. What are they?1. increased intracranial pressure 2. skeletal disorders 3. genetic disorders 4. endocrine disorders
In cases of markedly increased intracranial pressure, how do the anterior fontanelle feel?tense or even bulging
List the causes of increased intracranial pressure?1. hydrocephalus 2. subdural hematomas 3. porencephalic cysts (cystic space in the brain parenchyma that communicates with an enlarged adjacent ventricle) 4. tumors
How are skeletal disorders identified?by diffuse skeletal abnormalities, associated physical findgs and abnormal findings on radiographic exam
List the causes of skeletal disorders?1. rickets (vitamin D deficiency) 2. osteogenesis imperfecta 3. achondroplasia 4. cleidocranial dysplasia (autosomal dominant widening of the fontanelles with broad lateral cranial diameter and multiple wormian bones along the lambdoid suture)
List 5 genetic disorders that can cause delayed fontanelle closure?1. Trisomy 21 2. Trisomy 13 3. Trisomy 18 4. Russell-Silver syndrome 5. CDAGS syndrome
Trisomy 21 features?microgenia (abnormally small chin), oblique eye fissures with epicanthic skin folds, hypotonia, flat nasal bridge, single palmar fold, protruding tongue (due to small oral cavity), macroglossia, short neck, Bushfield spots (white spots on the iris), excessive joint laxity including atlanto-axial instability, excessive space between 1st and 2nd toes and short fingers
Trisomy 13 features?microcephaly, microphtalmia, cleft lip or cleft palate, malformed ears, polydactyly, rocker-bottom foot and other congenital malformations
Trisomy 18 features?severe psychomotor and growth retardation, microcephaly, microphthalmia, malformed ears, micrognathia or retrognathia, microstomia, distinctively clenched fingers and other congenital malformations
Russell-Silver syndrome features?poor growth, low birth weight, short height and differences in the size of the two sides of the body
CDAGS syndrome features?a rare autosomal recessive disorder characterized by Craniosynostosis and Clavicular hypoplasia, Delayed closure of the fontanelle, cranial Defects and Deafness, Anal anomalies, Genitourinary malformations, skin eruptions
Most common endocrine disorder causing delayed fontanelle closure?congenital hypothyroidism
Congenital hypothyroidism features?delayed growth and neurological developemtn, coarse facial features, thick,broad tongue, physically inactive
** Children with delayed closure of the anterior fontanelle with normal physical characteristics and a normal TSH should be evaluated for what? increased ICP
What imaging studies may be obtained?plain skull films (examine the cranial bones and sutures), ultrasound, CT and MRI can reveal abnormal fluid collections and masses.
If the above imaging is normal, what should be concluded?that this is likely a normal variant.
When should you consult a pediatric neurosurgeon?when the dx or presence of an abnormality is not clear
What are the majority of hydrocephalus secondary to? What is the treatment?1. obstruction 2. ventriculoperitoneal or ventriculoatrial shunt