Several different types of magnetic resonance imaging (MRI) may be employed in diagnosis: MRI without contrast, Gd contrast enhanced T1-weighted MRI (GdT1W) or T2-weighted enhanced MRI (T2W or T2*W). Non-contrast enhanced MRI is considerably less expensive than any of the contrast enhanced MRI scans. The gold standard in diagnosis is GdT1W MRI.

The reliability of non-contrast enhanced MRI is highly dependent on the sequence of scans, and the experience of the operator.

The condition is often diagnosed through an MRI or ultrasound. Consulting a specialist (in this case a gynecologist) is recommended.

Before the advent of MRI, electronystagmography and Computed Tomography were employed for diagnosis of acoustic neuroma.

Very few risk factors for choanal atresia have been identified. While causes are unknown, both genetic and environmental triggers are suspected. One study suggests that chemicals that act as endocrine disrupters may put an unborn infant at risk. A 2012 epidemiological study looked at atrazine, a commonly used herbicide in the U.S., and found that women who lived in counties in Texas with the highest levels of this chemical being used to treat agricultural crops were 80 times more likely to give birth to infants with choanal atresia or stenosis compared to women who lived in the counties with the lowest levels. Another epidemiological report in 2010 found even higher associations between increased incidents of choanal atresia and exposure to second-hand-smoke, coffee consumption, high maternal zinc and B-12 intake and exposure to anti-infective urinary tract medications.

Although rare, this condition is often treatable with surgery. In most cases, the blind hemivagina is opened, and the fluid drained.

Enlarged vestibular aqueducts are commonly picked up after newborn hearing screen when a child is identified as having a hearing loss. The hearing loss is commonly mixed and can be of any degree when first identified. The conductive component is due to a third window effect caused by the widened vestibular aqueduct.

Identification of the enlarged vestibular aqueduct in a child is usually by MRI scan which identifies the fluid within the endolymphatic duct and sac. CT scan may be needed to see the vestibular aqueduct clearly. In adults CT scan may be the first investigation.

In order to diagnose the cause of the enlarged vestibular aqueduct the physician will need a detailed family history, full examination to include vestibular examination and, if a bilateral finding, molecular genetic testing as appropriate. With unilateral enlarged vestibular aqueducts molecular genetic testing is currently not recommended.

MCDK is usually diagnosed by ultrasound examination before birth. Mean age at the time of antenatal diagnosis is about 28 weeks A microscopic analysis of urine in individuals with probable multicystic dysplastic kidney should be done. One meta-analysis demonstrated that unilateral MCDK occurs more frequently in males and the greater percentage of MCKD occur on the left side of the body.

There is no treatment to correct an enlarged vestibular aqueduct. Any hearing loss will need management with amplification and support in education and at work. If the hearing loss becomes severe to profound cochlear implants can be of significant value. Vestibular disturbance is usually short-lived and associated with head trauma but significant vestibular hypofunction may require rehabilitation.

People with enlarged vestibular aqueducts are advised to avoid head trauma where possible. This usually means avoiding contact sports such as boxing and rugby, but also horse riding, trampolining and other sports where head injury may occur. Some have symptoms when flying and should limit these activities if affected.

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.

Choanal atresia can be suspected if it is impossible to insert a nasal catheter.

Also, if one notices a continuous stream of mucus draining from one or both nostrils, it could be a sign of an atresia. Another common sign is cyanosis in an infant while breast feeding, as breathing is dependent on nasal patency in this situation.

Diagnosis is confirmed by radiological imaging, usually CT scan.

Typically, testing is first done to determine the quality of hearing. This can be done as early as in the first two weeks with a BAER test (Brain Stem Auditory Response Test). At age 5–6, CT or CAT scans of the middle ear can be done to elucidate its development and clarify which patients are appropriate candidates for surgery to improve hearing. For younger individuals, this is done under sedation.

The hearing loss associated with congenital aural atresia is a conductive hearing loss—hearing loss caused by inefficient conduction of sound to the inner ear. Essentially, children with aural atresia have hearing loss because the sound cannot travel into the (usually) healthy inner ear—there is no ear canal, no eardrum, and the small ear bones (malleus/hammer, incus/anvil, and stapes/stirrup) are underdeveloped. "Usually" is in parentheses because rarely, a child with atresia also has a malformation of the inner ear leading to a sensorineural hearing loss (as many as 19% in one study). Sensorineural hearing loss is caused by a problem in the inner ear, the cochlea. Sensorineural hearing loss is not correctable by surgery, but properly fitted and adjusted hearing amplification (hearing aids) generally provide excellent rehabilitation for this hearing loss. If the hearing loss is severe to profound in both ears, the child may be a candidate for a cochlear implant (beyond the scope of this discussion).

Unilateral sensorineural hearing loss was not generally considered a serious disability by the medical establishment before the nineties; it was thought that the afflicted person was able to adjust to it from birth. In general, there are exceptional advantages to gain from an intervention to enable hearing in the microtic ear, especially in bilateral microtia. Children with untreated unilateral sensorineural hearing loss are more likely to have to repeat a grade in school and/or need supplemental services (e.g., FM system – see below) than their peers.

Children with unilateral sensorineural hearing loss often require years of speech therapy in order to learn how to enunciate and understand spoken language. What is truly unclear, and the subject of an ongoing research study, is the effect of unilateral conductive hearing loss (in children with unilateral aural atresia) on scholastic performance. If atresia surgery or some form of amplification is not used, special steps should be taken to ensure that the child is accessing and understanding all of the verbal information presented in school settings. Recommendations for improving a child's hearing in the academic setting include preferential seating in class, an FM system (the teacher wears a microphone, and the sound is transmitted to a speaker at the child's desk or to an ear bud or hearing aid the child wears), a bone-anchored hearing aid (BAHA), or conventional hearing aids. Age for BAHA implantation depends on whether the child is in Europe (18 months) or the US (age 5). Until then it is possible to fit a BAHA on a softband

It is important to note that not all children with aural atresia are candidates for atresia repair. Candidacy for atresia surgery is based on the hearing test (audiogram) and CT scan imaging. If a canal is built where one does not exist, minor complications can arise from the body's natural tendency to heal an open wound closed. Repairing aural atresia is a very detailed and complicated surgical procedure which requires an expert in atresia repair. While complications from this surgery can arise, the risk of complications is greatly reduced when using a highly experienced otologist. Atresia patients who opt for surgery will temporarily have the canal packed with gelatin sponge and silicone sheeting to prevent closure. The timing of ear canal reconstruction (canalplasty) depends on the type of external ear (Microtia) repair desired by the patient and family. Two surgical teams in the USA are currently able to reconstruct the canal at the same time as the external ear in a single surgical stage (one stage ear reconstruction).

In cases where a later surgical reconstruction of the external ear of the child might be possible, positioning of the BAHA implant is critical. It may be necessary to position the implant further back than usual to enable successful reconstructive surgery – but not so far as to compromise hearing performance. If the reconstruction is ultimately successful, it is easy to remove the percutaneous BAHA abutment. If the surgery is unsuccessful, the abutment can be replaced and the implant re-activated to restore hearing.

Causes a ‘white reflex’ in the affected eye (leukocoria), prompting further investigation.

All newborns should have screening eye examinations, including an evaluation of the red reflexes.

- The red reflex test is best performed in a darkened room and involves shining a bright direct ophthalmoscope into both eyes simultaneously from a distance of 1– 2 ft. This test can be used for routine ocular screening by nurses, pediatricians, family practitioners, and optometrists.

- Retinoscopy through the child's undilated pupil is helpful for assessing the potential visual significance of an axial lens opacity in a pre-verbal child. Any central opacity or surrounding cortical distortion greater than 3 mm can be assumed to be visually significant.

- Laboratory Tests : In contrast to unilateral cataracts, bilateral congenital cataracts may be associated with many systemic and metabolic diseases. A basic laboratory evaluation for bilateral cataracts of unknown cause in apparently healthy children includes:

Alezzandrini syndrome is a very rare syndrome characterized by a unilateral degenerative retinitis, followed after several months by ipsilateral vitiligo on the face and ipsilateral poliosis. Deafness may also be present.

Congenital cystic eye (also known as "CCE" or "cystic eyeball") is an extremely rare ocular malformation where the eye fails to develop correctly "in utero" and is replaced by benign, fluid-filled tissue. Its incidence is unknown, due to the very small number of cases reported. An audit by Duke-Elder of the medical literature from 1880 to 1963 discovered only 28 cases. The term was coined in 1937 by the renowned ophthalmologist Ida Mann.

Embryologically, the defect is thought to occur around day 35 of gestation, when the vesicle fails to invaginate. Dysgenesis of the vesicle later in development may result in coloboma, a separate and less severe malformation of the ocular structures.

CCE is almost always unilateral, but at least 2 cases of bilateral involvement have been described. Patients may also present with skin appendages attached to the skin surrounding the eyes. Association with intracranial anomalies has been reported.

Treatment of CCE is usually by enucleation, followed by insertion of an ocular implant and prosthesis.

Individuals with CAVD can reproduce with the assistance of modern technology with a combination of testicular sperm extraction and intracytoplasmic sperm injection (ICSI). However, as the risk of either cystic fibrosis or renal agenesis is likely to be higher in the children, genetic counseling is generally recommended.

All cases reported appear to represent sporadic occurrence. There is no specific inheritance pattern. The male-to-female ratio of affected is 1.8:1 and is often diagnosed before the age of 9. The disorder affects the right and left sides of the maxilla almost equally.

MEWDS is a self limited disease with excellent visual recovery within 2-10 weeks. However residual symptoms including photopsia may persist for months.

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.

MCDK is not treatable. However, the patient is observed periodically for the first few years during which ultrasounds are generally taken to ensure the healthy kidney is functioning properly and that the unhealthy kidney is not causing adverse effects. In severe cases MCDK can lead to neonatal fatality (in bilateral cases), however in unilateral cases the prognosis might be better (it would be dependent on associated anomalies).

Persistent hyperplastic primary vitreous (PHPV), also known as Persistent Fetal Vasculature (PFV), is a rare congenital developmental anomaly of the eye that results

following failure of the embryological, primary vitreous and hyaloid vasculature to regress. It can be present in three forms: purely anterior (persistent tunica vasculosa lentis and persistent posterior fetal fibrovascular sheath of the lens), purely posterior (falciform retinal septum and ablatio falcicormis congenita) and a combination of both. Most examples of PHPV are unilateral and non-hereditary. When bilateral, PHPV may follow an autosomal recessive or autosomal dominant inheritance pattern.

The gene for Darwin's tubercle was once thought to be inherited in an autosomal dominant pattern with incomplete penetrance, meaning that those who possess the allele (version of a gene) will not necessarily present with the phenotype. However, genetic and family studies have demonstrated that the presence of Darwin's Tubercle may be more likely to be influenced by one's environment or developmental accidents than it is by genetics alone. There is no clear argument for whether the trait has significance in sexual dimorphism studies or age related studies. In some studies, there is clear data that Darwin's tubercle is not associated with sex. In contrast, others indicate that there is a correlation with sexual dimorphism between men and women, where men tend to have the tubercle more than women in some populations. Two studies indicate that older men tend to have greater expression of Darwin's tubercle than do older women.

The diagnosis of IP is established by clinical findings and occasionally by corroborative skin biopsy. Molecular genetic testing of the NEMO IKBKG gene (chromosomal locus Xq28) reveals disease-causing mutations in about 80% of probands. Such testing is available clinically.

In addition, females with IP have skewed X-chromosome inactivation; testing for this can be used to support the diagnosis.

Many people in the past were misdiagnosed with a second type of IP, formerly known as IP1. This has now been given its own name - 'Hypomelanosis of Ito' (incontinentia pigmenti achromians). This has a slightly different presentation: swirls or streaks of hypopigmentation and depigmentation. It is "not" inherited and does not involve skin stages 1 or 2. Some 33–50% of patients have multisystem involvement — eye, skeletal, and neurological abnormalities. Its chromosomal locus is at Xp11, rather than Xq28.

Trotter's syndrome is a cluster of symptoms associated with certain types of advanced nasopharyngeal carcinoma. The cause of pain is the mandibular nerve of the foramen ovale, through which the tumor enters the calvarium. Symptoms include the following:

1. Unilateral conductive deafness due to middle ear effusion

2. Trigeminal neuralgia due to perineural spread

3. Soft palate immobility

4. Difficulty opening mouth

Encephalocraniocutaneous lipomatosis (ECCL), otherwise known as Haberland syndrome, is a rare condition primarily affecting the brain, eyes, and skin of the head and face. It is characterized by unilateral subcutaneous and intracranial lipomas, alopecia, unilateral porencephalic cysts, epibulbar choristoma and other ophtalmic abnormalities.

It was named after Haberland and Perou who first described it.