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Related to fontanelle: sunken fontanelle


one of the membrane-covered spaces remaining at the junction of the sutures in the incompletely ossified skull of the fetus or infant. Actually there are two soft spots close together, representing gaps in the bone structure which will be filled in by bone during the normal process of growth. The anterior fontanelle is diamond shaped and lies at the junction of the frontal and parietal bones. This fontanelle usually fills in and closes between the eighth and fifteenth months of life. The posterior fontanelle lies at the junction of the occipital and parietal bones, is triangular in shape, and usually closes by the third or fourth month of life. Though these “soft spots” may appear very vulnerable, they may be touched gently without harm. Care should be exercised that they be protected from strong pressure or direct injury.
Fontanelles. From Jarvis, 2000.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


(fon'tă-nel'), [TA]
One of several membranous intervals between the angles and margins of the cranial bones in the infant; they include the midline anterior and posterior fontanelles, and the paired sphenoidal and mastoid fontanelles. See: cranial fontanelles.
[Fr. dim. of fontaine, fountain, spring]
Farlex Partner Medical Dictionary © Farlex 2012


A non-ossified area of membranous bone, in particular of the skull in an infant. Fonticulus is the accepted Terminologia Anatomica name; fontanelle is widely preferred in the working medical parlance.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


(fon'tă-nel') [TA]
One of several membranous intervals at the margins of the cranial bones in the infant.
Synonym(s): fonticulus [TA] .
[Fr. dim. of fontaine, fountain, spring]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


, fontanelle (fŏn″tă-nĕl′) [Fr. fontanelle, little fountain]
Enlarge picture
Any of the tough, fibrous membranes lying between the bones of the cranial vault of a fetus or infant. Fontanels, colloquially known as soft spots, allow an infant's skull to be compressed during passage through the birth canal. The fontanels ossify generally by age two. See: illustration

anterior fontanel

The diamond-shaped junction of the coronal, frontal, and sagittal sutures; it becomes ossified within 18 to 24 months.

posterior fontanel

The triangular fontanel at the junction of the sagittal and lambdoid sutures; ossified generally by age one.
Medical Dictionary, © 2009 Farlex and Partners


a gap in the skull bone where the brain and its membranes are covered only by skin. Young human infants possess an anterior fontanelle between frontal and parietal bones on top of the head, and a posterior fontanelle between occipital and parietal bones at the back of the head.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005


One of several "soft spots" on the skull where the developing bones of the skull have yet to fuse.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Caption: Figure 7: (a, b) Delayed closure of the sutures, widening of the anterior fontanelle, Wormian bones, sclerotic skull base, numerous supernumerary teeth, and malocclusion can be seen in the cranial radiographs (11 years).
A 5-year-old male child, second in birth order, born to nonconsanguineous couple, out of normal vaginal delivery presented to us with the complaints of open anterior fontanelle and short stature.
Diffuse osteopenia, prominent vascular markings in skull, thin and large calvarium with shallow diploic space, multiple wormian bones, small mandible with infantile obtuse angle and short ascending rami, hypoplastic facial bones, open cranial fontanelles, thin short clavicles, dwarfism, abnormally gracile ribs involving the posterior segments of the upper ribs, slender long bones, kyphosis, coxa valga, and progressive acroosteolysis of the terminal phalanges were the major roentgen findings previously reported.
She had a firm anterior fontanelle with a splayed sagittal suture.
This we call a fontanelle. But just because it is common does not make it right - contrary to some breeders' belief.
Measurement of head circumference is crucial in diagnosing developing hydrocephalus in these children, as the presence of an open fontanelle and sutures may sometimes mask the more obvious signs of raised ICP, and result in a surprisingly clinically healthy child despite significant pathology.
Out of which most of accessory maxillary ostia 70% were found in the anterior nasal fontanelle (ANF), 25% were found in posterior nasal fontanelle (PNF), and remaining 5% observed in hiatus semilunaris (HS).
The fontanelle, average ranging from 0.00 [+ or -] 0.00 to 95.55 [+ or -] 4.44, only occurred in groups that received cyclophosphamide associated or not to chlorophyllin.
[12] Brain growth, dural attachments, suture development and osteogenesis have all been reported to influence fontanelle development.
Professor Andy Petros, consultant paediatric intensivist at Great Ormond Street Hospital for Children, in London, worked with Kyriacou and his team on two of the optics devices: the newborn oesophageal sensor and the fontanelle sensor.