A lack of oxygen to the brain contributes to the formation of lesions usually near the three main cerebral arteries, located near the parietal lobe and occipital lobes of the brain. The cause of perinatal brain injuries includes: 

1. cerebral ischemia
2. cerebral hemorrhage
3. ascending intrauterine infections.Some risk factors for perinatal brain injuries include: low birth weight, preterm birth, poor perinatal cardiorespiratory fitness, and artificial ventilation. Cerebral ischemia
Cerebral ischemia occurs when the brain is not receiving adequate oxygen to continue normal functions. When this occurs, the body makes restoring oxygenated blood flow to life-sustaining organs a priority. The brain alters the diameter of major blood vessels to redistribute blood to key organs such as the brain, heart, and adrenal glands. If sympathetic nervous system activation does not produce any improvement, oxygen levels will continue to fall and disruptions to metabolism, other cellular processes, and overall functioning will ensue. Another serious result of inefficient blood flow is that cells do not receive adequate amounts of glucose. An immediate effect of low intracellular glucose is reduced ATP production in the cell. This effectively inactivates the Na-K pump, leading to the uptake of calcium ions by the cell. Continued influx of calcium serves to constitutively activate downstream effectors, including lipases, proteases, and endonucleases, whose actions eventually destroy the cell skeleton. Intracellular calcium concentrations are increased further due to the opening of glutamate-regulated ion channels.
Renpennings syndrome is a neurodevelopmental disorder recognised in males that causes intellectual disability, mild growth retardation with examples in the testes and head, and a somewhat short stature. The condition only affects males, starting at birth. Presentation
People with Renpennings typically begin learning language at an ordinary pace, but by the age of 3–4 they experience a regression in mental and physical development, such as mild low muscle tone resulting in elongated faces and rapid loss in the normal growth of the head (microcephaly). Small testes and short stature are also known to commonly occur. Genetics
It is associated with mutations in the PQBP1 gene. The gene product is a polyglutamine-binding protein involved in transcription and pre-mRNA splicing. The gene itself is located on the short arm of the X chromosome (Xp11.23). The most common mutations causing this condition occur in exon 4. Diagnosis
This diagnosis may be suspected on clinical grounds but should be confirmed by sequencing the PQBP1 gene. Treatment
There is no specific or curative treatment for this condition at present. Management is supportive

Epidemiology
This condition normally only occurs in males but a case in a female has been reported. History
This condition was first characterized in 1962. and later described by Hans Renpenning in 1963 after he documented these traits on many children in one family alone. See also
Lujan-Fryns syndrome
Fragile x syndrome

References


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