Microcephaly | The University Of Western Ontario

University:
The University Of Western Ontario
Course:
ANAT 2200B | Systemic Anatomy of the Human Body
Academic year:

2022
Views:

298

Pages:

3
Author:

Kyuwon J.

Microcephaly ● Neurodevelopmental condition on head circumference ○ Smaller than expected on sex and age ■ >2 standard dev below mean ■ Severe microcephaly ○ Reduced brain growth ● Normal vs microcephalic brain developments ● Primary microcephaly ○ Present at birth ○ Abnormal neurogenesis ○ Genetic effect sometimes ● Secondary microcephaly ○ Queried ○ Normal head size at birth ○ Postnatal failure on brain growing ■ Injury, infection, insult in metabolic Etiology ● Genetic causes ○ Autosomal recessive microcephaly ■ MCPH genes ○ Chromosomal abnormalities ■ Trisomy 13 ■ Trisomy 18 ■ Trisomy 21 ● Less common ● Intrauterine Infections ○ TORCH ○ Zika virus ⇒ classic associations ○ Cytomegalovirus ■ CMV ○ Toxoplamosis ○ Rubella ○ Herpes simplex virus ● Maternal + Environmental factors ○ Alcohol exposures ■ Fetal alcohol spectrum disorders ○ Drug exposures ○ Severe malnutritions ○ Radiation ionizing ● Perinatal/Postnatal causes ○ Hypoxic ischemic encephalopathy ○ Neonatal infections ○ Metabolic disorders ■ Untreated Pathophysiology ● Reduction on neuronal proliferations ● Neuronal migration ● Increase in apoptosis ○ Neural progenitor cells ● Cortical volume on gyral complexity Mx ● Neurological ○ Developmental delay ○ Intellectual disability ○ Seizure ○ Hypertonia / hypotonia ○ Poor coordination ● Craniofacial ○ Sloping forehead ○ Disproportionately small skull ○ Facial features ■ Appear relatively preserved