Defects of Development of Face and Neck

Cleft lip (cheiloschisis) — the fissure of the soft and/or hard palate.

A through cleft of superior lip and palate (cheilognathopalatoschisis) — cleft of a lip, alveolar process and palate. All these clefts can be unilateral, bilateral, complete, partial, and clefts of the palate — latent (submucosal). At through clefts there is a wide communication between cavities of the mouth and nose, that sharply complicates sucking, swallowing, and subsequently speaking.

The slanting cleft of the face (paranasal, lateral, slanting coloboma) is a rare, usually unilateral defect of development. Nasal and oral-ocular forms are distinguished. Sometimes a cleft spreads to frontal and temporal area.

The anomalad middle cleft of the face — complete or covered by a skin longitudinal defect of the back of the nose, sometimes transitory on an alveolar process and forehead. In a number of cases, the defect combines with front cerebral hernia (encephalocele anterior).

Proboscis — a tubular cutaneous formation, which is disposed in the area of root of the nose (nose is usually absent having one blindly closed opening. It usually accompanies heavy defects of central nervous system (for example, cyclopia).

Atresia of choanae — absence or narrowing of the back nasal opening. Often combines with other defects of development of skull and face bones. Bilateral аtresia of choanae — a heavy defect of development excluding possibility of breast-feeding, as in the child the breathing is disturbed.

Agnathia — аplasia of mandible, a rare and usually lethal defect combined with macrostomia — an unusually large mouth crack, absence or significant hypoplasia of tongue and synotia (an extremely low localization of auricular conchae with their almost horizontal position).

Aglossia — absence of the tongue as an isolated defect is not encountered, but is observed at severe defects of the face in nonviable fetus.

Macroglossia — the increased sizes of the tongue, usually accompanied by expressed plication of its mucous membrane. It is often observed in children with Down’s syndrome and hypothyroid. It can be the consequence of hem- and lymphangioma of the body of tongue or its root.

The defects of teeth are frequent and varied. The following are possible: anomalies of number, size and form, disturbance of tooth structure, anomaly of position, disturbance of terms of eruption and growth.

Anomalies of salivary glands — аplasia, hypoplasia of glands and dystopia of the gland in the area of neck.

The defects of auricles include dysplasia, deformation, аplasia. Gross disorders of development of auricles are usually combined with defects of development of internal and middle ear.

Congenital defects of neck — a short neck, congenital muscular torticollis, pterygoid (wing-shaped) neck (longitudinal folds on the lateral surfaces of neck, quite often descending to a shoulder), cysts and fistulas of neck — cavities from the remnants of thyrohyoid duct, from non- reduced rests of the first and second branchial crack; dermoid cysts of neck.

Defects of Development of the Central Nervous System. Аnencephaly — absence of the large brain, bones of vault of skull and soft tissues. In place of cerebral substance a connective tissue with cystic cavities is usually disposed (Fig. 164).

Exencephaly — absence of bones of vault of skull (acrania) and soft covers of the head, therefore the large hemispheres swell as separate sites covered with the meninx vasculosa.

Inioncephaly — absence of occipital bone (inion — nape), as a result the most part of cerebrum is disposed in the area of back cranial fossa and partially in the overhead of vertebral canal.

Cranial-cerebral hernia — hernial protrusion in the area of defect of the skull bones. Hernia is localized usually in places of connection of cranial bones. The following are distinguished: а) meningocele — a hernial sack is presented by meninx fibrosa and skin, and cerebrospinal liquid in its content; b) meningoencephalocele- one or another part of cerebrum bulges in a hernia sack.

Аplasia and hypoplasia of callous body — a partial or complete absence of basic comissural joint, as a result the ventricular system in the area of III ventricle remains open.

Defects of a callous body can be accompanied by convulsive syndrome, mental retardation. They can also proceed without symptoms.

Pachygyria — a condition in which the convolutions of the cerebral cortex are abnormally large. Thus the secondary and tertiary gyri are fully absent, sulci are short, shallow and relatively direct, the structure of cytoarchitectonics of cerebral cortex is disturbed.

Аgyria — absence of fissures, gyri, and a layer-by-layer structure of cerebral cortex in the cerebral hemispheres. Clinical signs: failure of swallowing, muscular hypotension, spasms, mental underdevelopment. The majority of children die within the first year of life.

Мicrocephalia — reduction of weight, sizes and histological structures of the brain. The primary and secondary microcephalia are distinguished. To primary one the hereditary forms of microcephalia refer, to secondary one — microcephalia developed due to organic damage of the brain of various etiology. The most frequent reasons of secondary microcephalia are the infections during pregnancy, (toxoplasmosis, rubeola, cytomegalia), various intoxications, hormonal disturbances, hypoxia.

Congenital defects of development of the olfactory analyzer — arrhinencephaly (aplasia of olfactory bulbs, furrows, tracts). More often it is encountered as a component of hereditary syndromes of multiple defects.

Congenital defects of development of medulla oblongata — aplasia and hypoplasia of pyramids and olives, which usually accompany severe disturbances of telencephalon.

The defects of cerebellum development — hypoplasia, structural changes — are seldom encountered.

The defects of development of spinal cord and spinal column — most frequent are dysraphia (spina bifida) (Fig. 165), which are connected with nonclosure of medullar tube. Usually these defects refer to back parts of spinal column, when the arches and spinal processes are absent. In the area of defect the spinal cord is usually deformed and it turns out to be open or located directly under soft tissues (muscles, skin), which it often accretes with.

There are also cystic clefts of spine, when in the area of cleft a hernia sack forms, which wall is presented with skin and cranial pia mater, and contents — with a cerebro-spinal liquid. In the lumbar and sacral parts of the spinal column there can be latent clefts of vertebra. Thus hernial diverticula are absent, and the defects are closed by unchanged muscles and skin. Dysraphia and other severe damages of spinal cord are accompanied by failure of activity of anal and urethral sphincters, muscle hypoplasia of lower extremities and talipes, trophic disorders.

Аmielia — a complete absence of the spinal cord with preservation of dura mater, and spinal ganglia. Amielia is usually combined with аnencephaly.

Hydromielia — hydrocephaly of the spinal cord.

Syringomielia — the presence in the spinal cord of cavities of different size. The walls of cavities are formed by glial tissue. The cavities are usually located in the area of the neck part of the spinal cord and have a tendency to spread, thus resulting in destruction of the brain structures, and progressing gliosis round the central canal.

Diplomyelia — doubling of the spinal cord in the area of cervical or lumbar thickening. Rarer the whole spinal cord is doubled. Both brains are located in one bed consisting of pia mater and dura mater, here and there connected by glial tissue, rather well developed and having all characteristic components for brain.