Feature | Advanced Visualization | December 02, 2015

CT and 3-D Printing Aid Surgical Separation of Conjoined Twins

For the first time, CT imaging and 3-D printing technology have been combined to help plan the surgical separation of conjoined twins

3-D printing, CT dataset, conjoined twins, surgical separation, physical model

3-D color segmentation of CT data with 3-D model used to help separate the conjoined twins.

3-D print, conjoined twins, RSNA 2015

3-D printed model of the conjoined twins created from CT datasets that were used to surgically separate them.

RSNA 2015, 3-D printing, Stratasys Connex 500, conjoined twins, surgical separation

The Stratasys Connex 500 3-D printer used to create the anatomical models from CT scans.

December 2, 2015 — A combination of detailed computed tomography (CT) imaging and 3-D printing technology has been used for the first time in the surgical planning for separation of conjoined twins, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA).

Conjoined twins, or twins whose bodies are connected, account for approximately one of every 200,000 live births. Survival rates are low and separating them through surgery is extremely difficult because they often share organs and blood vessels.

Specialists at Texas Children's Hospital in Houston brought a new approach to these challenges when they set out to surgically separate Knatalye Hope and Adeline Faith Mata, conjoined twins from Lubbock, Texas. Knatalye and Adeline were born on April 11, 2014, connected from the chest all the way down to the pelvis.

"This case was unique in the extent of fusion," said the study's lead author, Rajesh Krishnamurthy, M.D., chief of radiology research and cardiac imaging at Texas Children's Hospital. "It was one of the most complex separations ever for conjoined twins."

To prepare for the separation surgery, Krishnamurthy and colleagues performed volumetric CT imaging with a 320-detector scanner, administering intravenous contrast separately to both twins to enhance views of vital structures and help plan how to separate them to ensure survival of both children. They used a technique known as target mode prospective EKG gating to freeze the motion of the hearts on the images and get a more detailed view of the cardiovascular anatomy, while keeping the radiation exposure low.

"The CT scans showed that the babies' hearts were in the same cavity but were not fused," Krishnamurthy said. "Also, we detected a plane of separation of the liver that the surgeons would be able to use."

The team translated the CT imaging results into a color-coded physical 3-D model with skeletal structures and supports made in hard plastic resin, and organs built from a rubber-like material. The livers were printed as separate pieces of the transparent resin, with major blood vessels depicted in white for better visibility. The models were designed so that they could be assembled together or separated during the surgical planning process. The surgical team used the models during the exhaustive preparation process leading up to the surgery.

On February 17, a little more than 10 months after they were born, the Mata twins underwent surgical separation by a team of more than 26 clinicians, including 12 surgeons, six anesthesiologists and eight surgical nurses. The official separation took place approximately 18 hours into the 26-hour surgery.

The 3-D models proved to be an excellent source of information, as there were no major discrepancies between the models and the twins' actual anatomy.

"The surgeons found the landmarks for the liver, hearts and pelvic organs just as we had described," Krishnamurthy said. "The concordance was almost perfect."

Krishnamurthy expects the combination of volumetric CT, 3-D modeling and 3-D printing to become a standard part of preparation for surgical separation of conjoined twins, although barriers remain to its adoption.

"The 3-D printing technology has advanced quite a bit, and the costs are declining. What's limiting it is a lack of reimbursement for these services," he said. "The procedure is not currently recognized by insurance companies, so right now hospitals are supporting the costs."

Besides assisting clinicians prepare for surgery, the 3-D model also served another important function: helping the twins' parents, Elysse and John Eric Mata, understand the process.

"When I showed the mother the model and explained the procedure, she held my hand and thanked me," Krishnamurthy recalled. "They said, 'For the first time, we understand what is going to happen with our babies.'"

Knatalye Hope returned home in May 2015 and her sister Adeline Faith came home a month later. They are both doing well and have a Facebook page, "Helping Faith & Hope Mata," with updates on their progress.

Co-authors on the study are Nicholas Dodd, B.S.; Darrell Cass, M.D.; Amrita Murali; and Jayanthi Parthasarathy, B.D.S., M.S., Ph.D.

For more information: www.radiologyinfo.org

Related Content

#COVID19 #Coronavirus #2019nCoV #Wuhanvirus #SARScov2

Getty Images

Feature | Coronavirus (COVID-19) | April 07, 2020 | By Melinda Taschetta-Millane and Dave Fornell
In an effort to keep the imaging field updated on the latest information being released on coronavirus (COVID-19), th
#COVID19 #Coronavirus #2019nCoV #Wuhanvirus #SARScov2  The first of three clinical scenarios presented to the panel with final recommendations. Mild features refer to absence of significant pulmonary dysfunction or damage. Pre-test probability is based upon background prevalence of disease and may be further modified by individual’s exposure risk. The absence of resource constraints corresponds to sufficient availability of personnel, personal protective equipment, COVID-19 testing, hospital beds, and/or ve

 The first of three clinical scenarios presented to the panel with final recommendations. Mild features refer to absence of significant pulmonary dysfunction or damage. Pre-test probability is based upon background prevalence of disease and may be further modified by individual’s exposure risk. The absence of resource constraints corresponds to sufficient availability of personnel, personal protective equipment, COVID-19 testing, hospital beds, and/or ventilators with the need to rapidly triage patients. Contextual detail and considerations for imaging with CXR (chest radiography) versus CT (computed tomography) are presented in the text. (Pos=positive, Neg=negative, Mod=moderate). [Although not covered by this scenario and not shown in the figure, in the presence of significant resources constraints, there is no role for imaging of patients with mild features of COVID-19.] Image courtesy of the journal Radiology

News | Coronavirus (COVID-19) | April 07, 2020
April 7, 2020 — A multinational consens...
#COVID19 #Coronavirus #2019nCoV #Wuhanvirus #SARScov2 Chest CT findings of pediatric patients with COVID-19 on transaxial images. (a) Male, 2 months old, 2 days after symptom onset. Patchy ground-glass opacities GGO in the right lower lobe

Chest CT findings of pediatric patients with COVID-19 on transaxial images. Male, 2 months old, 2 days after symptom onset. Patchy ground-glass opacities GGO in the right lower lobe. Image courtesy of Radiology: Cardiothoracic Imaging

News | Coronavirus (COVID-19) | April 06, 2020
April 6, 2020 — Children and teenagers with COVID-19...
#COVID19 #Coronavirus #2019nCoV #Wuhanvirus #SARScov2 Sonogram taken under rib cage shows liver (grey) with curved diaphragm-lung border (white). Arrows point to vertical B lines (white) demonstrating diseased lung tissue. The more B lines the worse the disease. Healing is measured by reduction in the number of B lines.

Sonogram taken under rib cage shows liver (grey) with curved diaphragm-lung border (white). Arrows point to vertical B lines (white) demonstrating diseased lung tissue. The more B lines the worse the disease. Healing is measured by reduction in the number of B lines.

News | Coronavirus (COVID-19) | April 06, 2020
April 6, 2020 — Robert L.
Recommended best practices for nuclear imaging departments under the COVIF-19 pandemic have been issues by the ASNC and SNMMI. #COVID19 #ASNC #SNMMI #Coronavirus #SARScov2
News | Coronavirus (COVID-19) | April 03, 2020
April 3, 2020 — A new guidance document on best practices to maintain safety and minimize contamination in nuclear im
An example of Philips’ TrueVue technology, which offers photo-realistic rendering and the ability to change the location of the lighting source on 3-D ultrasound images. In this example of two Amplazer transcatheter septal occluder devices in the heart, the operator demonstrating the product was able to push the lighting source behind the devices into the other chamber of the heart. This illuminated a hole that was still present that the occluders did not seal.

An example of Philips’ TrueVue technology, which offers photo-realistic rendering and the ability to change the location of the lighting source on 3-D ultrasound images. In this example of two Amplazer transcatheter septal occluder devices in the heart, the operator demonstrating the product was able to push the lighting source behind the devices into the other chamber of the heart. This illuminated a hole that was still present that the occluders did not seal. Photo by Dave Fornell

Feature | Radiology Imaging | April 02, 2020 | By Katie Caron
A new year — and decade — offers the opportunity to reflect on the advancements and challenges of years gone by and p
#COVID19 #Coronavirus #2019nCoV #Wuhanvirus

Getty Images

Feature | Coronavirus (COVID-19) | April 02, 2020 | Jilan Liu and HIMSS Greater China Team
Information technologies have played a pivotal role in China’s response to the novel coronavirus...