Rare Case: Malformed Twin Removed from a 1-Year-Old’s Brain

Rare Case: Malformed Twin Removed from a 1-Year-Old’s Brain

A highly unusual medical case was recently reported in China, where doctors surgically removed a malformed twin from the brain of a 1-year-old girl. This rare condition, known as fetus-in-fetu (FIF), occurs when a twin is absorbed into the body of its sibling during early development.

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1. Symptoms and Diagnosis

The little girl exhibited:

• Developmental delays – slower physical and mental growth than expected.
• An unusually large head – a common sign of increased intracranial pressure.

Doctors conducted imaging scans and discovered a mass inside her brain. Upon closer examination, the mass contained bones resembling a spine, arms, and even finger-like structures.

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2. What is Fetus-in-Fetu?

FIF is an extremely rare condition occurring in about 1 in 500,000 births. It happens when one twin is absorbed into the body of the other during early pregnancy. Instead of developing as a separate fetus, the twin becomes encased within its sibling.

Key characteristics of FIF:

• Often mistaken for a tumor.
• Identified by the presence of recognizable body parts (e.g., bones, limbs).
• Usually found in the abdomen but can develop in other areas.

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3. A Rare Location: Twin Inside the Brain

Most FIF cases involve the abdominal region, but in this instance, the twin developed inside the girl’s brain. This is one of fewer than 200 cases ever recorded worldwide.

Challenges of this case:

• Extremely delicate location – surgery in the brain is far riskier than in the abdomen.
• Increased intracranial pressure – leading to developmental delays.
• Potential neurological effects – the longer the mass remains, the greater the impact on the child’s brain function.

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4. Surgical Removal and Outcome

Doctors successfully surgically removed the malformed twin, which contained partially developed bones and other structures. The surgery was highly complex due to the sensitive nature of the brain.

While the long-term effects on the child are unknown, early removal may improve her development and overall prognosis.

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5. The Rarity of This Case

This case adds to the very limited number of documented FIF occurrences inside the brain. Scientists and doctors continue to study such cases to understand:

• How and why one twin becomes absorbed into the other.
• The genetic and developmental factors behind FIF.
• The best surgical and treatment approaches for future cases.

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Conclusion

The discovery of a malformed twin inside a child’s brain is an extraordinary and extremely rare event in medical history. This case highlights the complexity of human development and the medical challenges that arise from such rare conditions.