Familial alobar holoprosencephaly, also known as cyclopia, is an uncommon and fatal congenital disability as well as an uncommon type of holoprosencephaly (HPE) that happens as a consequence of the unfinished separation of the prosencephalon into two distinct parts of hemispheres throughout organogenesis, resulting in a failed cleavage of the orbital cavity into the two cavities of the eyes. This is a gradual anterior terminal seizure of the neural plate. 

Moreover, the nose is usually absent or substituted for a nonfunctional nose in the shape of a proboscis. A proboscis that arises over the middle part of the eye is a symptom of rhinocephaly or rhinencephaly. Although familial alobar holoprosencephaly occurs in one out of every 16,000 live babies, cyclopia occurs in as little as one out of every 100,000 infants, like stillbirths.


The most distinguishing characteristic of familial alobar holoprosencephaly is a single or partly split eye filling each orbital. This eye is frequently situated wherein the nose would usually be. The nose could be missing or substituted with a non-functioning nose in the shape of a proboscis located over the eye in this disease. This illness, however, can harm additional structures in the face and head.

Other familial alobar holoprosencephaly symptoms include the following:

  • Additional toes or fingers
  • Cleft lip and palate
  • Nose flattened
  • Eyes that are not present
  • Eyes that are pretty close together
  • Over the eye is a proboscis, or nose-like feature.
  • A missing nose

Several occurrences of cyclopia are associated with omphalocele, a disorder in which the infant’s internal organs protrude over the belly button. Similarly, renal dysplasia can occur when fluid-filled sacs substitute a baby’s kidneys.


An ultrasound could be used to diagnose familial alobar holoprosencephaly. This examination is performed while your kid is still in the womb. The ultrasound may also detect indicators of brain and internal organ problems.

In addition, an MRI could be used to make a diagnosis in particular instances. When a prenatal diagnosis is not established, cyclopia might be detected during neonatal physical testing after birth.


Familial alobar holoprosencephaly has no known cause or effective treatment. Instead, healthcare professionals focus treatment on the distinct symptoms that each HPE-affected child has.

The following are common interventions for symptom management:

  • Anti-seizure drugs
  • Physical and occupational therapy
  • Ventriculoperitoneal VP Shunt
  • Reconstructive plastic surgery
  • Medications to address hormonal abnormalities in the pituitary gland.

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