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3D-printed Abdominal Cavity Model for Liver Transplantation
with the exact size. However, since 3D reconstruction every case fitted properly to the 3D model as well as the
without 3D printing can also give an advanced view to actual recipient’s cavity.
the surgeon, whether 3D printing significantly enhances Pediatric LT cases were also good candidates for
the surgeon’s insight is questionable, especially when 3D printing. Unlike adult recipients, 3D printing was
time and cost of the 3D printing are taken into account. performed on both hemiabdomens. Liver grafts, whether
3D printing in LT was first introduced in the literature they were left hemiliver, extended left lateral liver, or
of Zein et al. . In the study, the surgical team printed reduced liver graft of extended left lateral liver, were
[18]
the graft liver as well as the recipient’s original liver and printed as per the surgeon’s plan.
compared them to the actual livers. The study showed The case presented in Figure 3E was a perfect
high level of resemblance of the 3D printed model to situation where 3D printed model can be beneficial. In
the graft. However, how to use the technology was up a patient with a distorted space, well-matched GRWR
to the clinicians. The study published by Wang et al. can be a misleading factor that can lead to devastating
[19]
showed that 3D printing technology can be used in situation of large-for-size syndrome. The space of the
pediatric LT for surgical planning. The surgical team patient’s right liver fossa which underwent contracture
printed the abdominal cavity and planned liver graft and after chronic empyema was somewhat similar to the
evaluated whether the surgery can be performed safely. 8-year-old female recipient’s liver fossa (Table 2). The
The outcome showed that 3D printing can be practically GRWR of the donor’s right liver was 1.63 % while
used during clinical practice. However, the study focused the actual printed right liver far exceeded the spatial
on recreating the abdominal cavity as realistic as possible boundaries of the 3D printed abdominal cavity.
and the reported time for manufacturing was about two Based on Table 1, adult recipients and pediatric
days in printing the model half the size of the actual recipients have distinct characteristics, which require
abdominal cavity. different management from the surgical team. 3D printing
Our 3D printed model was originally planned to be for the patients was also different between adult and
used for small donors who might accept large liver graft pediatric patients. While adult recipients mostly required
during DDLT. Therefore, the key to success was to print printing of the right hemi-abdomen, pediatric patients
the model as fast as possible with low cost. We prepared required printing of the entire abdomen. This is basically
3D printed model of the intra-abdominal cavity in due to the type of graft used. When whole liver graft or right
advance for the patients with high MELD scores, who are liver graft is used, the main place will be placed is right
expected to undergo DDLT. Nevertheless, there are times liver fossa. However, the left liver graft is placed on the
when allocation and transplantation occur abruptly. Case midline of the abdominal cavity, which points to the need
No. 14 (Table 2) was an example of which the transplant to design both hemi-abdomens. Slice distance was also
surgeon requested for a 3D printed model 6 h before significantly narrower in the pediatric recipients. However,
surgery. Therefore, we planned a 3D model with a wider the fundamental process for manufacturing the 3D printed
slice distance to reduce printing time. This case showed model is similar, and the time and the amount of filaments
the possibility that our model could be much more time- required are also similar between the two groups. This
saving in the future. shows that our 3D printed model can be utilized properly
Three cases were performed successfully with for both adult and pediatric recipients with minimal error.
modification of the 3D printed model. During the three The limitation of this study is that our study only
cases, one case required a reduction graft which fit showed descriptive data of our patients whose abdominal
perfectly to the small abdominal cavity. After the three cavity was 3D printed. This study did not compare the
cases, we designed a prospective study to use the 3D impact of using 3D printed model between an experimental
printed model for potential adult recipients in the waiting group and a control group. The reason for not showing such
list with small intra-abdominal cavity and pediatric LT comparative data is that the patients who were expected
recipients. The goal of our 3D printed model was not to benefit from 3D printing were apparently patients
to mimic every detail of the human body or liver graft, whose abdominal cavity has a potential to be small and
but only to focus on giving the surgeon the idea of the who were selected to be prepared in our 3D imaging and
actual size of cavity and graft. The 3D printed model printing laboratory. Even though our 3D model simulates
was used for comparing the size of the graft to the size the patient’s intra-abdominal space, the model does not
of the recipient’s intra-abdominal cavity during organ reflect the actual elasticity of the abdominal wall and the
harvest operation from deceased donor. Decision to diaphragm. This could lead to a practical question on
either receive whole liver or just part of the liver or to whether the real graft could fit into the recipient, and as
withdraw the chance was made by the donor surgeon with a result, surgeons could be conservative while making
the assistance of the 3D printed model. After back-table decision. The surgeon should take into account the elasticity
procedure, evaluation for the fitness was carried out, and of the muscular structures comprising the liver fossa when

126 International Journal of Bioprinting (2022)–Volume 8, Issue 4