The unspoken assumption is that by the age of five, unusual behaviors will either resolve or develop into diagnosable autism. However, some parents view the PDD label as no more than a euphemism for autism spectrum disorders, problematic because this label makes it more difficult to receive aid for early childhood intervention. Classification
The pervasive developmental disorders were:
Pervasive developmental disorder not otherwise specified (PDD-NOS), which includes atypical autism, and is the most common (47% of autism diagnoses);
Typical autism, the best-known;
Asperger syndrome (9% of autism diagnoses);
Rett syndrome; and
Childhood disintegrative disorder (CDD).The first three of these disorders are commonly called the autism spectrum disorders; the last two disorders are much rarer, and are sometimes placed in the autism spectrum and sometimes not.In May 2013, the Diagnostic and Statistical Manual–5th Edition (DSM-V) was released, updating the classification for pervasive developmental disorders. The grouping of disorders, including PDD-NOS, Autism, Asperger Syndrome, Rett Syndrome, and CDD, has been removed and replaced with the general term of Autism Spectrum Disorders. The American Psychiatric Association has concluded that using the general diagnosis of ASD supports more accurate diagnoses. The combination of these disorders was also fueled by the standpoint that Autism is characterized by common symptoms and should therefore bear a single diagnostic term. In order to distinguish between the different disorders, the DSM-V employs severity levels. The severity levels take into account required support, restricted interests and repetitive behaviors, and deficits in social communication. PDD and PDD-NOS
There is a division among doctors on the use of the term PDD.
Other known environmental conditions that have led to anophthalmia are maternal vitamin A deficiency, exposure to X-rays during gestation, solvent abuse, and exposure to thalidomide. Chromosome 14
An interstitial deletion of chromosome 14 has been known to occasionally be the source of anophthalmia. The deletion of this region of chromosome has also been associated with patients having a small tongue, and high arched palate, developmental and growth retardation, undescended testes with a micropenis, and hypothyroidism. The region that has been deleted is region q22.1-q22.3. This confirms that region 22 on chromosome 14 influences the development of the eye. Classifications
There are three classifications for this condition:

Primary anophthalmia is a complete absence of eye tissue due to a failure of the part of the brain that forms the eye. Secondary anophthalmia the eye starts to develop and for some reason stops, leaving the infant with only residual eye tissue or extremely small eyes which can only be seen under close examination. Degenerative anophthalmia the eye started to form and, for some reason, degenerated. One reason for this occurring could be a lack of blood supply to the eye. Prenatal diagnosis
Ultrasounds
Ultrasounds can be used to diagnose anophthalmia during gestation. Due to the resolution of the ultrasound, it is difficult to diagnose it until the second trimester. The earliest time to detect anophthalmia this way is approximately 20 weeks. Amniocentesis
It is possible to diagnose prenatally with amniocentesis, but it may not show a correct negative result. Amniocentesis can only diagnose anophthalmia when there is a chromosomal abnormality.