Alex Simpson’s extraordinary journey of surviving 20 years with almost no brain has astonished doctors and inspired people worldwide.
A woman from Nebraska, born without most of her brain, has defied every medical prediction by celebrating her 20th birthday — despite doctors warning that she wouldn’t live past the age of four. Her remarkable case has drawn international attention, shedding light on an extremely rare condition that few survive beyond early childhood.
Alex Simpson was diagnosed with hydranencephaly — an exceptionally rare brain disorder — just two months after her birth. Medical scans revealed that nearly all her brain tissue was missing, leaving only a small portion intact.
The Cleveland Clinic describes hydranencephaly as a defect in which a baby is missing “certain portions of their brain called the cerebral hemispheres.” In Alex’s case, the condition was far more severe. Her father explained that only a tiny amount of brain tissue — “about half the size of a pinky finger” — remains in her cerebellum, the part of the brain responsible for coordination and movement.
Despite the staggering odds, Alex marked her 20th birthday this month, surrounded by her family. Her parents believe the only explanation for her survival is “love” and “faith.”
Most children diagnosed with this condition do not survive long after birth. Life expectancy is often measured in months or just a few short years. Infants with hydranencephaly are typically diagnosed shortly after delivery when doctors observe severe developmental delays or neurological symptoms.
What is Hydranencephaly?
Hydranencephaly is a rare condition that develops around the 12th week of pregnancy, during the crucial stage when a baby’s brain begins to form. It occurs when damage to the developing nervous system disrupts normal brain growth.
In babies affected by this disorder, large portions of the brain fail to develop and are replaced by cavities filled with cerebrospinal fluid (CSF). This fluid, which typically cushions and protects the brain, fills the empty spaces where brain tissue should be.
Over time, these fluid-filled sacs can cause the skull to expand, resulting in one of the condition’s most visible signs — an abnormally large or swollen head. The buildup of CSF is a defining feature of hydranencephaly.
Most cases are diagnosed after birth, typically between two and four months of age, when symptoms start to appear. In some instances, the condition is detected prenatally through ultrasound scans. When discovered during pregnancy, parents often face the heartbreaking decision of whether to continue, as doctors usually warn that life expectancy will be extremely limited.
How to Recognize Hydranencephaly Symptoms
Infants with hydranencephaly usually present three major symptoms that alert doctors to possible neurological issues. These early warning signs prompt further testing and diagnosis.
The most common indicator is an enlarged or irregularly shaped head caused by excess cerebrospinal fluid. Doctors may also observe hypertonia — increased muscle tone that makes a baby’s limbs feel stiff or rigid — as well as excessive irritability.
As the condition progresses, babies may suffer from seizures, paralysis, and loss of vision as the limited brain structure struggles to maintain essential bodily functions.
According to the childhood disability organization Contact, diagnosis is typically confirmed through an ultrasound of the infant’s head, which reveals large fluid-filled cavities and shows how much brain tissue is missing.
In severe cases, EEG scans — which record brain activity — detect little to no function, indicating that the remaining tissue cannot produce electrical signals.
What Causes Hydranencephaly?
The precise cause of hydranencephaly remains unclear, though experts have identified several possible contributing factors. There is often no single event or genetic explanation behind it.
Researchers suggest it may result from complications during pregnancy, such as restricted blood flow to the brain or the loss of a twin in the womb. Other potential causes include early bleeding in the fetal brain, oxygen deprivation, or vascular blockages that disrupt brain development.
Genetic inheritance is generally not linked to hydranencephaly. Most medical literature attributes the condition to issues with blood or oxygen flow during the second trimester.
In very rare instances, similar brain damage can occur after birth due to severe illness or trauma, such as meningitis, stroke, or head injury.
How Rare Is Hydranencephaly — and How Is It Treated?
Hydranencephaly is among the world’s rarest neurological disorders, estimated to occur in only one out of every 5,000 to 10,000 births. Its severity varies, but most cases are fatal within the first year of life.
Babies with the most severe forms often die shortly after delivery. For those who survive longer, doctors may insert a shunt — a small tube that drains excess cerebrospinal fluid from the skull — to relieve pressure and reduce swelling.
There is currently no cure for hydranencephaly. Treatment focuses on managing symptoms, preventing complications, and improving quality of life through supportive care, anti-seizure medication, and regular medical supervision. Families often depend on therapy and specialized care to ensure comfort and stability for as long as possible.
Most infants with hydranencephaly never reach their first birthday — making Alex Simpson’s 20-year survival nothing short of miraculous. Her story continues to inspire families and medical professionals alike, proving that sometimes, love and determination can transcend even the most impossible odds.
