A temporal-bone CT using thin slices makes it possible to diagnose the degree of stenosis and atresia of the external auditory canal, the status of the middle ear cavity, the absent or dysplastic and rudimentary ossicles, or inner ear abnormalities such as a deficient cochlea. Two- and three-dimensional CT reconstructions with VRT and bone and skin-surfacing are helpful for more accurate staging and the three-dimensional planning of mandibular and external ear reconstructive surgery.

Other diseases have similar characteristics to Treacher Collins syndrome. In the differential diagnosis, one should consider the acrofacial dysostoses. The facial appearance resembles that of Treacher Collins syndrome, but additional limb abnormalities occur in those persons. Examples of these diseases are Nager syndrome and Miller syndrome.

The oculoauriculovertebral spectrum should also be considered in the differential diagnosis. An example is hemifacial microsomia, which primarily affects development of the ear, mouth, and mandible. This anomaly may occur bilaterally. Another disease which belongs to this spectrum is Goldenhar syndrome, which includes vertebral abnormalities, epibulbar dermoids and facial deformities.

Treatment is usually confined to such surgical intervention as may be necessary to help the child to develop e.g. jaw distraction/bone grafts, ocular dermoid debulking (see below), repairing cleft palate/lip, repairing heart malformations or spinal surgery. Some patients with Goldenhar syndrome will require assistance as they grow by means of hearing aids or glasses.

Stem cell grafting (womb tissue grafting) has been successfully used to "reprogram" eye dermoids, effectively halting the regrowth of eye dermoids.

These tissues that grow on the eye are "mis-programmed" cells (sometimes tooth or nail cells instead of eye cells).

Figueroa and Pruzanksky classified HFM patients into three different types:

- Type I : Mild hypoplasia of the ramus , and the body of the mandible is slightly affected.

- Type II : The condyle and ramus are small, the head of the condyle is flattened , the glenoid fossa is absent , the condyle is hinged on a flat, often convex, infratemporal surface , the coronoid may be absent.

- Type III: The ramus is reduced to a thin lamina of bone or is completely absent. There is no evidence of a TMJ.

Prevalence ranges from 1 in 3500 to 5600 live births. Male-female ratio is found to be 3:2.

Depending upon the treatment required, it is sometimes most appropriate to wait until later in life for a surgical remedy – the childhood growth of the face may highlight or increase the symptoms. When surgery is required, particularly when there is a severe disfiguration of the jaw, it is common to use a rib graft to help correct the shape.

According to literature, HFM patients can be treated with various treatment options such functional therapy with an appliance, distraction osteogenesis, or costochondral graft. The treatment is based on the type of severity for these patients. According to Pruzanksky's classification, if the patient has moderate to severe symptoms, then surgery is preferred. If patient has mild symptoms, then a functional appliance is generally used.

Patients can also benefit from a Bone Anchored Hearing Aid (BAHA).

It can be detected by the naked eye as well as dental or skull X-Ray testing.

Three main support groups of this syndrome are the ASGA in Australia, The Association for Children with Genetic Disorders in Poland, and the Association of People of Genetic Disorders in Greece.

Diagnosis can be made solely on the basis of history and physical examination in people who present with only facial asymmetry. For those who report neurological symptoms such as migraine or seizures, MRI scan of the brain is the imaging modality of choice. A diagnostic lumbar puncture and serum test for autoantibodies may also be indicated in people who present with a seizure disorder of recent onset.

The treatment of soft tissue parts of midface anomalies is often a reconstruction from a skin flap of the cheek. This skinflap can be used for other operations in the further, as it can be raised again and transposed again. In the treatment of midface anomalies there are generally more operations needed. Bone tissue reconstruction of the midface often occurs later than the soft tissue reconstruction. The most common method to reconstruct the midface is by using the fracture/ incision lines described by René Le Fort. When the cleft involves the maxilla, it is likely that the impaired growth will result in a smaller maxillary bone in all 3 dimensions (height, projection, width).

Hemihypertrophy, now more commonly referred to as hemihyperplasia in the medical literature, is a condition in which one side of the body or a part of one side of the body is larger than the other to an extent considered greater than the normal variation. As it is difficult to establish a set clinical criteria for diagnosis of hemihyperplasia, the dictum is often used that the clinician should be able to see the asymmetry "from the end of the bed".

Hemihyperplasia is a congenital overgrowth disorder and the asymmetry can range from mild to severe. It is important to establish a diagnosis because hemihyperplasia is associated with an increased risk for embryonal tumors, mainly Wilms tumor and hepatoblastoma. Due to the heightened tumor risk, there is a tumor screening protocol that is recommended for all children with isolated hemihyperplasia and Beckwith-Wiedemann Syndrome. Some of the other syndromes associated with hemihyperplasia may also follow this tumor surveillance protocol. The recommended tumor surveillance protocol is:

1. Any child with suspected isolated hemihyperplasia should be referred to a clinical geneticist for evaluation.

2. Abdominal ultrasound every 3 months until 7 years

3. Serum alpha fetoprotein measurement every 3 months until 4 years

4. Daily caretaker abdominal examination at the discretion of the provider/parent

In some cases, children with hemihyperplasia may have different leg lengths. There are two main surgical options for the treatment of uneven leg lengths- shortening and lengthening. Epiphysiodesis, which involves removing part of the growth plate of the longer leg, allowing the shorter leg to "catch up", may be performed on patients still able to grow. Bone resection is performed on patients who have no growth left and involves removing part of the bone. Leg lengthening procedures are more painful, involving the insertion of pins to be turned, moving parts of the bone apart (Ilizarov's Method). This process is reserved mainly for patients with a discrepancy greater than 4 cm, although some leg lengthening procedures are now done cosmetically. Non-surgical options include attachment of a lift to the shoe, allowing the patient to walk normally.

Children with hemihypertrophy may also develop scoliosis, a curvature of the spine.

Hemifacial hyperplasia is believed to be a minor form of hemihypertrophy.

While not always pathological, it can present as a birth defect in multiple syndromes including:

- Catel–Manzke syndrome

- Bloom syndrome

- Coffin–Lowry syndrome

- congenital rubella

- Cri du chat syndrome

- DiGeorge's syndrome

- Ehlers-Danlos syndrome

- fetal alcohol syndrome

- Hallermann-Streiff syndrome

- Hemifacial microsomia (as part of Goldenhar syndrome)

- Juvenile idiopathic arthritis

- Marfan syndrome

- Noonan syndrome

- Pierre Robin syndrome

- Prader–Willi syndrome

- Progeria

- Russell-Silver syndrome

- Seckel syndrome

- Smith-Lemli-Opitz syndrome

- Treacher Collins syndrome

- Trisomy 13 (Patau syndrome)

- Trisomy 18 (Edwards syndrome)

- Wolf–Hirschhorn syndrome

- X0 syndrome (Turner syndrome)

Some individuals have preaxial polydactyly in the feet (unilateral in one, bilateral in 13), consisting of a small extra biphalangeal toe, in most cases with an associated rudimentary extra metatarsal, lying in a soft tissue web between the hallux and second toe. In some cases, this was accompanied by hypoplasia of the head of the first metatarsal and absence of both phalanges of the hallux.

There are several options for treatment of mouth anomalies like Tessier cleft number 2-3-7 . These clefts are also seen in various syndromes like Treacher Collins syndrome and hemifacial microsomia, which makes the treatment much more complicated. In this case, treatment of mouth anomalies is a part of the treatment of the syndrome.

The cause of Primrose syndrome is currently unknown. This condition is extremely rare and seems to spontaneously occur, regardless of family history.

In the case studied by Dalai et al. in 2010, it was found that an abnormally high amount of calcitonin, a hormone secreted by the thyroid gland to stabilize blood calcium levels, was present in the blood serum. This suggests that the thyroid gland is releasing an abnormal amount of calcitonin, resulting in the disruption of calcium level homeostasis. No molecular cause was found, but an expanded microarray analysis of the patient found a 225.5 kb deletion on chromosome 11p between rs12275693 and rs1442927. Whether or not this deletion is related to the syndrome or is a harmless mutation is unknown. The deletion was not present in the patient's mother's DNA sample, but the father's DNA was unavailable.

The common symptoms in all reported cases of primrose syndrome include ossified pinnae, learning disabilities or mental retardation, hearing problems, movement disorders (ataxia, paralysis, and parkinsonism among others (likely due, in part, to calcification of the basal ganglia), a torus palatinus (a neoplasm on the mouth's hard palate), muscle atrophy, and distorted facial features. Other symptoms usually occur, different in each case, but it is unknown whether or not these symptoms are caused by the same disease.

Hemifacial hypertrophy (also termed facial hemihypertrophy, facial hemihyperplasia, or Friedreich's disease) abbreviated as (HFH) is rare congenital disease characterized by unilateral enlargement of the head and teeth. It is classified as true HFH (THFH) with unilateral enlargement of the viscerocranium, and partial HFH (PHFH) in which not all structures are enlarged. Hemifacial hypertrophy can cause a wide spectrum of defects or may involve only muscle or bone. it is usually treated surgically. It is believed to be a minor form of hemihypertrophy.

Affected individuals may benefit from autologous fat transfer or fat grafts to restore a more normal contour to the face. However, greater volume defects may require microsurgical reconstructive surgery which may involve the transfer of an island parascapular fasciocutaneous flap or a free flap from the groin, rectus abdominis muscle (Transverse Rectus Abdominis Myocutaneous or "TRAM" flap) or latissimus dorsi muscle to the face. Severe deformities may require additional procedures, such as pedicled temporal fascia flaps, cartilage grafts, bone grafts, orthognathic surgery, and bone distraction. The timing of surgical intervention is controversial; some surgeons prefer to wait until the disease has run its course while others recommend early intervention.

Neurocristopathy is a diverse class of pathologies that may arise from defects in the development of tissues containing cells commonly derived from the embryonic neural crest cell lineage. The term was coined by Robert P. Bolande in 1974.

Accepted examples are piebaldism, Waardenburg syndrome, Hirschsprung disease, Ondine's curse (congenital central hypoventilation syndrome), pheochromocytoma, paraganglioma, Merkel cell carcinoma, multiple endocrine neoplasia, neurofibromatosis type I, CHARGE syndrome, familial dysautonomia, DiGeorge syndrome, Axenfeld-Rieger syndrome, Goldenhar syndrome (a.k.a. hemifacial microsomia), craniofrontonasal syndrome, congenital melanocytic nevus, melanoma, and certain congenital heart defects of the outflow tract, in particular.

Multiple sclerosis has also been suggested as being neurocristopathic in origin.

The usefulness of the definition resides in its ability to refer to a potentially common etiological factor for certain neoplasms and/or congenital malformation associations that are otherwise difficult to group with other means of nosology.

Clinical:

Patients often present with a history of fever of unknown origin, muscular weakness, poor development, abnormal dentition, normal serum calcium, phosphorus, and alkaline phosphatase levels. Associated clinical findings also include glaucoma, photosensitivity, heart block, foot deformities, and chronic psoriasiform skin lesions.

Radiological:

Classic radiologic findings were first described by Edward B. Singleton and David Merten in 1973.

Typical radiographic appearances include skeletal demineralization, expanded shafts of the metacarpals and phalanges with widenend medullary cavities, cardiomegaly, and intramural calcification of the proximal aorta with occasional extension into the aortic or mitral valves.

Other commonly seen radiographic findings include shallow acetabular fossa, subluxation of the femoral head, coxa valga, hypoplastic radial epiphysis, soft tissue calcifications between the radius and ulna, constriction of the proximal radial shaft, acro-osteolysis, and equinovarus foot deformities.

Singleton Merten Syndrome is an autosomal dominate genetic disorder with variable expression with an onset of symptoms during childhood.

Aural atresia is the underdevelopment of the middle ear and canal and usually occurs in conjunction with microtia. Atresia occurs because patients with microtia may not have an external opening to the ear canal, though. However, the cochlea and other inner ear structures are usually present. The grade of microtia usually correlates to the degree of development of the middle ear.

Microtia is usually isolated, but may occur in conjunction with hemifacial microsomia, Goldenhar Syndrome or Treacher-Collins Syndrome. It is also occasionally associated with kidney abnormalities (rarely life-threatening), and jaw problems, and more rarely, heart defects and vertebral deformities.

Hearing loss with craniofacial syndromes is a common occurrence. Many of these multianomaly disorders involve structural malformations of the outer or middle ear, making a significant hearing loss highly likely.

Hypochondrogenesis is a severe genetic disorder causing malformations of bone growth. The condition is characterized by a short body and limbs and abnormal bone formation in the spine and pelvis.

Hypochondrogenesis is a subtype of collagenopathy, types II and XI, and is similar to another skeletal disorder, achondrogenesis type 2, although the spinal changes seen in hypochondrogenesis tend to be somewhat milder.

The goal of medical intervention is to provide the best form and function to the underdeveloped ear.