Medicine chapter 123

Question 1

developmental defects associated with failure of the anterior and posterior neuropore to close during the 24th to 26th days of gestation

Answer 1

neural tube defects

Question 2

what is displacement of the hindbrain tonsils more than 5 mm below the foramen magnum

Answer 2

chiari malformation

Question 3

what results from an anomalous hilum terminal that causes either lack of normal ascent of the conus medullar is to the L1 vertebral level or an ischemic or metabolic disturbance of the caudal spinal cord

Answer 3

tethered spinal cord

Question 4

what are some associated spinal anomalies with tethered spinal cord

Answer 4

diastematomyelia, spinal lipomas, dermal sinuses, and fibrolipomas

Question 5

what is cystic cavitation of the central portion of the spinal cord

Answer 5

syringomyelia

Question 6

what is the dilation of the central canal

Answer 6

hydromelia

Question 7

what is the classic presentation of syringomyelia and hydromyelia

Answer 7

sensory loss in the neck, arms or legs

Question 8

what are some disorders of ventral induction

Answer 8

holoprosencephaly, agenesis of corpus callous, and septa-optic dysplasia

Question 9

what are some migration abnormalities that occur during the 2-4th month

Answer 9

lissencephaly, schizencephaly, polygyria, and pachygyria

Question 10

what are some symptoms of migration abnormalities

Answer 10

cognitive delay, spasticity, seizures

Question 11

what are some clinical manifestations of holoprosencephaly

Answer 11

dysmorphic features, mental retardation, pituitary dysfunction

Question 12

what are some clinical manifestations of lissencephaly

Answer 12

mental retardation, epilepsy, motor disability

Question 13

what is the major clinical manifestation of band heterotopia

Answer 13

epilepsy

Question 14

what is the major clinical manifestation of polymicrogyria

Answer 14

epilepsy and cognitive delay

Question 15

what are the major clinical manifestations of schizencephaly

Answer 15

mental retardation, spasticity, epilepsy

Question 16

what are the classic features of RETT syndrome

Answer 16

loss of hand function and stereotypic hand wringing

Question 17

what disorder is an X-linked dominant disorder caused by mutation in MeCP2 that functions as a transcriptional repressor

Answer 17

RETT syndrome

Question 18

what is the distinct appearance of Fragile X syndrome

Answer 18

macrocephaly with long narrow face, and prominent ears, pubertal macroorchidism, and joint laxity

Question 19

what chromosome is NF1 gene located on

Answer 19

17q

Question 20

what are the clinical manifestations of neurofibromatosis type 1

Answer 20

learning disabilities, ADD, macrocephaly, epilepsy

Question 21

what chromosome is the NF2 gene located on

Answer 21

22q

Question 22

what is the gene product for TSC1

Answer 22

hamartin

Question 23

what is the gene product for TSC2

Answer 23

tuberin

Question 24

what is surge-weber syndrome characterized by

Answer 24

upper facial vascular nevus, leptomeningeal angioma, and ocular abnormalities

Question 25

what is the autosomal dominant disorder caused by defective tumor suppressor gene on chromosome 3p25-p26

Answer 25

von hippel lindau disease