The causes of delayed closure of fontanelle are mainly the following ah: congenital malformations such as midbrain aqueduct stenosis, diaphragm formation or atresia, interventricular foramen atresia malformation (fourth ventricle median foramen or lateral hollow atresia), cerebrovascular malformation, spina bifida, cerebellar subungual hernia, etc. Intrauterine infections such as viral, protozoal, and syphilitic meningitis that are not controlled early, fibrous hyperplasia after intracranial hemorrhage, and malabsorption of intracranial hemorrhage from birth injuries. Late closure of fontanel, mainly refers to the baby has passed 18 months, but the fontanel has not yet closed, mostly seen in rickets, cretinism. The late closure of fontanel, a few is caused by hydrocephalus or other causes of increased intracranial pressure, should go to the hospital for further examination. The human brain skull is composed of 8 bones, of which the paired temporal bone and parietal bone, not paired frontal bone, sieve bone, butterfly bone and occipital bone. The newborn’s skull is not fully developed, and there are many gaps between the bones, and the bones of the skull cover are connected by connective tissue membranes, and the gaps between these bones are called cranial fontanelles. The largest cranial fontanelle is prismatic, located in the front of the sagittal suture, called fontanelle (frontal fontanelle). In addition, there is a posterior fontanelle (occipital fontanelle) at the intersection of the sagittal suture and the herringbone suture, which is triangular in shape. In front of the parietal bone, there is an anterior lateral fontanelle (butterfly fontanelle). There is a posterior lateral fontanelle (mastoid fontanelle) at the posterior inferior corner of the parietal bone. The anterior fontanelle closes at 1 to 2 years of age after birth, and the rest of the fontanelles close shortly after birth. Usually, abnormal fontanelle closures are discovered during the course of pediatric care. It is important to note that it is not possible to find out whether the fontanelle is closing abnormally in a single visit to the doctor, but it takes several visits to the doctor to determine how big it is and whether it is indeed closing or not increasing with the growth of the head circumference.