In order to properly answer your question, a short lesson in infant anatomy. The bones
of a baby’s skull are held together by fibers called sutures. Mother nature designed
things this way for two reasons. First, it allows the newborn’’s head to be flexible and
compressible enough to pass through the birth canal. Second, it gives the baby’s skull
room to grow as the brain enlarges during the first years of life. The “soft spot” or
fontanelle is the area on the infant’’s head where the skull bones do not completely
come together. The larger, diamond shaped soft spot on the tope of the head is called
the ““anterior fontanelle.”” It can close as early as nine months of age or as late as two
years (average 12 to 14 months). Another smaller fontanelle is located on the back of
the head and is called the ““posterior fontanelle.”” It generally can no longer be felt by
the fourth month of life.
Early closure of the soft spot could mean your child has a condition called
craniosynostosis (cranio= head, synostosis = the union of two or more bones to form a
single bone). This disorder occurs when one or more of the skull bones joins
prematurely before the brain has completed its growth. The danger is that left
untreated, compression of the brain can occur.
In our opinion, your child’’s doctor was correct in obtaining the x-rays. Occasionally, the
scan will reveal that the soft spot has not really closed and is just difficult to feel. On the
other hand, if the sutures have indeed closed prematurely, then we presume your
doctor will refer your baby to a neurosurgeon for evaluation of the problem.
Surgery to correct craniosynostosis is not always necessary. However, when it is
performed, the reason is to prevent pressure on the brain, provide room for the brain to
grow, and cosmetically improve the shape of the child’’s skull.
Because of the potential seriousness of premature closure of the sutures, we would tend to agree with your physician that appropriate x-rays and CT scan are necessary to establish the diagnosis. We are not aware of any harmful effets of the x-ray to the child, and in this case, the benefits far outweight any possible risk.