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Stott et al. Art Int Surg 2023;3:207-16 https://dx.doi.org/10.20517/ais.2022.42 Page 211

resectability of pancreatic and periampullary tumour reliably assess the resectability of
periampullary neoplasms pancreatic and periampullary tumors

AR: Augmented reality; CT: computed tomography; HPB: hepatobiliary and pancreatic surgery; IPDA: inferior pancreaticoduodenal artery; MI-3DVS: medical image three-dimensional visualization system; NS:
navigation system; PDAC: pancreatic ductal adenocarcinoma.

3D visualisation in 7 cases. According to the authors, the surgical plan did not change after adjustments were made with 3D visualisation and that was the
actual surgery performed.

Current definitions of resectability in PDAC relate to the involvement of the major arteries and veins: superior mesenteric artery (SMA), coeliac axis and the
superior mesenteric vein (SMV) by the tumour. Determining resectability is therefore based on preoperative imaging, which is primarily via pancreas protocol
CT. Of course, borderline resectable cases may undergo trial dissection, but with the increasing evidence of the benefit of neoadjuvant chemotherapy in the
borderline resectable cohort, the need for accurate assessment is paramount. It has been suggested that by a standard pancreas protocol CT scan, the accuracy
[7,8]
of determination of resectability compared to histopathological findings ranges from 73% to 83% . This is probably limited by intra-observer variability with
regard to determining vessel involvement. It has also been reported that up to 8% of pancreatectomies do not proceed beyond initial laparotomy or
[9]
laparoscopy due to metastatic disease that was not previously seen on conventional imaging . Fang et al. showed in a prospective study of 80 pancreatic and
periampullary tumours, how 3D reconstruction using the MI-3DVS system changed perceived resectability in 10 of the cases, with 10 more tumours being
deemed resectable when analysed using the 3D reconstructed images . At operation, all tumours deemed resectable by 3D visualisation were indeed
[10]
resectable. They thus claim that the sensitivity and specificity of 100% is significantly different from the 90% sensitivity and 82.5% specificity of conventional
2D computed tomography.

A novel technique of 3D reconstruction is cinematic rendering. Cinematic rendering moves beyond standard 3D reconstruction and generates life-like images
from CT scans. It applies technology taken from the Pixar animation studios and provides additional accurate displays of shadows, textures, and an increased
depth of field. Post-processing technology allows highly modifiable windowing so that, for example, a specific area of interest, its vascular supply, and the
adjacent tissues can be delineated in more depth. This textual assessment has been evaluated in the assessment of pancreatic cysts and can be used to
differentiate between solid and cystic pancreatic tumours, and the internal architecture of cystic lesions to appreciate septation and nodularity, for example.
This may allow, for example, pancreatic cysts on a surveillance programme to be evaluated more clearly prior to endoscopic ultrasound assessment.

Javed et al. (2022) discuss the use of Cinematic rendering at the Johns Hopkins Hospital pancreas multidisciplinary clinic . Cinematic rendering allows more
[11]
accurate arterial assessment in borderline resectable cases, particularly of the SMA, by allowing accurate distinction between the perineural invasion of the
[11]
dense perineural sheath and lymphatic channels surrounding the SMA from true tumour invasion [Figure 2] . They suggest that R0 resection can be achieved
with perineural invasion through divestment or periadventitial dissection and the ability to determine this preoperatively is achievable through cinematic