Separated twins who were born joined at the head are going home for Thanksgiving just five months after incredibly risky 11-hour surgery in which one almost died

  • Erin and Abby Delaney were born as craniopagus twins, conjoined at the head
  • They were attached at the top of their skull, which is the most rare form of conjoined twins 
  • Surgeons at Children's Hospital of Philadelphia were able to successfully separate the twins during an 11-hour surgery in June
  • Erin was discharged from the hospital in October, and has been staying in a nearby Ronald McDonald House with their mother Heather
  • Their father Riley has been traveling from North Carolina for visits 
  • Abby was discharged on Monday after battling infections and a brain bleed
  • Now they are all going home to Raleigh, North Carolina, for Thanksgiving 

They underwent one of the riskiest separation surgeries ever, with a significant chance that one of both wouldn't make it.

Now, just five months after their 11-hour operation in Philadelphia, once-conjoined twin girls Erin and Abby Delaney are heading home to North Carolina for Thanksgiving.

Erin was discharged at the beginning of October, and has been staying with their mother Heather in the nearby Ronald McDonald House. Their father Riley, however, has been traveling back and forth between the ward and his work in Raleigh.

On Monday, surgeons declared Abby had recuperated enough to go home. 

'Riley and I are so grateful for the care our girls have received here and so excited to take them home - just in time for the holidays,' Heather said.  

Holiday joy: Heather and Riley embrace their daughters Erin (left) and Abby (right) as they are discharged from hospital after 485 days (about five months) in hospital recovering

Erin (left) and Abby (right) were born as craniopagus conjoined twins. This is the rarest form of conjoined twins where the babies are attached at the top of the skull

Surgeons at Children's Hospital of Philadelphia were concerned about performing the dangerous surgery for fear they would lose both of the babies 

Craniopagus conjoined twins and how rare the births are

Craniopagus conjoined twins are babies who are connected at the top of the cranium.

This condition occurs in about ten to 20 babies in every million of births in the United States.

An estimated two to six percent of conjoined twins are attached at the top of the head, making it the rarest form. 

Overall, conjoined twins are more likely to be female. 

With craniopagus twins, they are always genetically identical and share the same sex.

Few craniopagus twins survive the birth because of how they are attached. 

About 40 percent are stillborn and an additional 33 percent die after birth, normally due to organ failure or abnormalities. 

But 25 percent have been known to survive and even have the option to be separated depending on where they are attached at the skull. 

Advances in brain imaging and neurosurgical techniques have made these separation surgeries more possible.  

The one-year-olds were born on July 24, 2016, via cesarean section as craniopagus twins, which is the most rare form of conjoined twins where they are attached at the top of the skull.

They were 10 weeks early and weighed two pounds each.

Surgeons at the Children's Hospital of Philadelphia separated the twins on June 7 when they were 11 months old, making it one of the earliest separations of craniopagus twins ever.

Half a year on, Erin is in therapy to gain mobility and speech. Her recovery has been easier because she has more of her skull intact than Abby.

Abby, on the other hand, has a tougher road where she has battled a brain bleed and multiple infections.

Surgeons say they are optimistic about both of them recovering well - a feat they weren't always 100 percent certain would be possible.   

Craniopagus conjoined twins is the rarest form where the babies are connected at the cranium.  

Doctors warned parents Heather and Riley, from Mooresville, North Carolina, that separation surgery could kill one or both of the twins.

'This is scary, and we're scared, but we can't let fear limit our ability to operate. We have to do the operation that needs to be done,' said neurosurgeon Dr Gregory Heuer to CBS News.

Dr Heuer and his team inserted a balloon into the twins' skulls to help expand the skin before the separation surgery.

This procedure stretched the skin around that area in preparation of separating the heads. 

The surgeons performed the surgery earlier than others because younger children have a better chance of surviving and healing.  

The Children's Hospital of Philadelphia had previously performed 24 separation surgeries, and it formed a team of about 30 people for the lengthy procedure.

During the surgery, the surgeons almost lost Abby because she started severely bleeding after she was separated from her sister. 

Because of how the twins were attached, Erin received the sagittal sinus instead of Abby. 

The sagittal sinus is responsible for draining the blood from the brain and cranial bones. 

Parents Heather and Riley Delaney remained hopeful that the surgery would be successful. Heather said on her website that holding her girls for the first time was one of the best experiences. Pictured left is mother Heather with Erin (left) and Abby (right) this month. Pictured right is father Riley with Erin (left) and Abby (right) in September

As part of surgery preparations, the surgeons inserted balloons into the twins skulls to expand the skin around the area. This is them before the surgery 

This has impacted Abby's recovery in the last four months since the surgery. 

Both twins were put into an induced medical coma for a week after the procedure to help their brain's recover from the separation.

Erin's coma was lifted first and Heather, her mother, was able to hold her for the first time.

'The emotions that welled up inside me at that moment, I can't even describe,' Heather wrote on her website. '(The nurse) was offering to give me the moment I had always dreamed of since the moment I found out I was pregnant.'

Abby was taken out of her coma that same day, just a couple hours after her sister. 

The biggest worry after the surgery was the twins could contract an infection in their brain around the area that was operated on. 

To prevent this from happening, hospital staff washed Erin's brain once and Abby's twice to keep the area as clean as possible.   

Since then, Abby has had a harder time recovering than her sister. 

She has suffered from a brain bleed, three respiratory viruses, a blood infection and other complications that have kept her in the hospital for longer.

Erin also experienced her own difficulties while recovering from the surgery, but she was released from the hospital on October 1 because of her progress.

The twins were born on June 24, 2016 during a cesarean section. They were ten weeks early and weighed only two pounds. Pictured is the twins with their father Riley four months after they were born in October 2016

Now that the sisters are separated from each other, they are able to go through rehab to improve their ability to speak, walk and hold their body up. Pictured is Erin (left) and Abby (right) earlier this month

Both of the twins are going through occupational, physical and speech therapy to gain functions that were unattainable while attached. 

Erin can now sit up on her own for 10 to 15 seconds and lift her head up. She also is able to reach for toys and roll onto her stomach.

Abby can hold her head up and roll onto her stomach from one side. 

Over the next few years, the twins are expected to have plastic and reconstructive surgeries to replace some of the missing bones in their skulls.  

'The girls are inspiring,' Heather said to Fox 29. 'As their parents, it is very neat for Riley and me to have a front row seat to this and watch them overcome these incredible obstacles.

'We cannot wait to see what their future holds.'

Pictured left to right is Riley, Abby, Erin and Heather

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