8/12/2019 Masters 20111

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HOLOPROSENCEPHALY: THEFACEPREDICTSTHEBRAIN

Jeanne B. Masters, RN, MSN, CCRN, CNRN, Neuroscience/Trauma Intensive Care Unit

St. Lukes Hospital & Health Network, Bethlehem, PA

ABSTRACT

OBJECTIVES

BIBLIOGWHAT

WHEN

WHY

WHERE

WHATELSE

WH

SUMM

Holoprosencephaly (HPE) is a developmental

defect of the embryronic forebrain, or

prosencephalon, that is commonly associated with

midfacial defects. HPE can present within a broadspectrum of clinical severity. The severity of the

effect on the brain is often reected in craniofacial

abnormalities. This has led to use of the phrase

The Face Predicts The Brain. This phrase is

generally but not always accurate.

Children with severe HPE generally do not

survive beyond early infancy, but milder forms are

more compatible with life. Virtually all surviving

individuals have some developmental decits. HPE

arises from disruption of normal development of

the rostral neural tube during early embryogenesis.

Research into the pathophysiology of HPE

has revealed multiple teratogenic and genetic

causes. A case presentation illustrates the typical

facial anomalies and developmental challengesassociated with HPE.

Describe clinical features of HPE.

Review embyronic development of face, skull, and

forebrain.

List associated genetic and teratogenic factors.

Illustrate a case of long-term survival. The defect in c leavage inuences the development of

later structures. Associated complications include:

Agenesis of corpus callosum

Arrhincephaly

Hydrocephalus

Chiari malformationMental retardation

Pituitary/Hypothalamic dysfunction

Seizures

Spasticity

Feeding difculties

Hypogonadism

Holoprosencephaly (HPE) refers to a groupof related disorders that share in common an

incomplete or absent division of the embryonic

forebrain (prosencephalon).

HPE results from incomple

of midline CNS structures

associated with mid-facial

based upon the severity o

quoted statement The F

reects the diagnostic sign

anomalies. This statement

reversed to indicate the im

induction of facial features

the Face.

HPE results from disruption of normal cleavage

and differentiation processes during early

embryogenesis, between 3rd and 8th week of

gestation.

HPE may occur individually or as a component of a

larger disorder. Ongoing research suspects primary

cause to be both genetic and environmental:

Genetic

Trisomy 13

Trisomy 18

Shh gene mutationEnvironmental

Maternal diabetes

Early pregnancy substance abuse

Radiation exposure

Viral infections

Teratogenics, e.g. Retinoic Acid

The clinical picture is highlighted by midline facial

hypoplasia. The development of face, skull, and

front of brain are interconnected; therefore, typical

facial anomalies are correlated with the degree ofHPE and have prognostic importance. In general

HPE results in substantial morbidity and mortality.

Severe HPE is not compatable with life.

Alberstone, Cary D., Benzel, Edward 1.

Michael P. Anatomic Basis of NeurologThieme Medical Publishers, Inc.

Fitzgerald, M. J., Gruner, Gregory, and2.

Neuroscience (5th Ed.) 2007. St. Louis

Stal, S., Hollier, L.H. Jr., Cole, P., and 3.

Holoprosencephaly. Retrieved Jan. 29

content/topic 4.

Tegay, D.H., Cohen, H.L., and Rosovs4.

Jan. 4, 2010 from //emedicine.medsca

G.R. is a case illustration of m

age 20. His associated anom

of corpus callosum, congenita

hydrocephalus, hypotelorism, and mitral valve prolapse. Spe

environmental causes were n

advanced maternal age. Desp

challenges and dysmorphic fa

maintained a high functioning

personality endeared him to fa

Vo-Tech School and place of

history included recurrent rev

repair of his temporal bone de

demise resulted from tension

creating mass effect.

Figure 3. The Face Predicts the Brain. Primitive nasal

structure (proboscis) associated with HPE illustrated by CT Scan.

Figure 2. HPE spectrum

Most severe form (cyclopia) to mildest form (hypotelorism).

Figure 1. Holoprosencephaly 5th week.3

Distinct lateral cerebral hemispheres fail to develop.