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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.


(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]


/fon·ta·nelle/ (fon″tah-nel´) a soft spot, such as one of the membrane-covered spaces remaining at the junction of the sutures in the incompletely ossified skull of the fetus or infant.


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.


(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]


, 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.


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.


One of several "soft spots" on the skull where the developing bones of the skull have yet to fuse.

fontanelle, fontanel

a soft spot; skin and membrane-covered spaces remaining at the junction of the sutures, especially between the frontal and parietal bones in the incompletely covered skull of the fetus or neonate. This fontanelle usually closes after birth but in hydrocephalus and in some miniature breeds of dogs, particularly Chihuahuas, it may remain open. Called also fonticulus, molera.
References in periodicals archive ?
Physical examination revealed wide open anterior fontanelle measuring 4.
Apart from the ostia, the fontanelle may be used to create alternate passage which re-establishes ventilation and drainage during therapy of maxillary sinusitis.
This study assessed variations in AF size in newborn Igbo babies in south-eastern Nigeria, with the aim of establishing baseline values and relating the findings to some factors reported to affect fontanelle size.
The haematoma did not require evacuation and the infant was admitted for 48 hours of neurological observation, during which time she was asymptomatic, the fontanelle remained soft and a cranial ultrasound showed no evidence of mass effect.
X-ray skull revealed frontal and parietal bossing, open sutures and fontanelle.
Congenital subgaleal cysts over the anterior fontanelle in Nigerians.
Popular complexes have included Cherry Lane, Riverwalk, Heatherwood, Fontanelle, Continental, Racquet Club, and Castlerock Village in Wenatchee: Ironwood, Stoneridge, Edgewater, Canyon Creek, and Ambercrest in East Wenatchee.
The fontanelle (soft spot) may be tense or bulging.
Severe dehydration, not drinking and sunken eyes or fontanelle (the soft spot on a baby's head).
If the lambdoid suture fuses, the brain is forced to expand into the mastoid fontanelle just below it.
A more detailed neurosonographic evaluation is done in additional coronal and sagittal planes, visualised ideally with transvaginal ultrasound through the anterior fontanelle.
In contrast to Milton's, Fontanelle's writings reveal a kind of ideological progress since in them the human 'creating mind takes over the role of the biblical God who is not otherwise mentioned' (145); unlike Milton, Fontanelle offers no 'confirmation of an authoritarian godhead' (147), although the Miltonic flights of imagination seem also to have been repressed.