Imaged guided surgery during arteriovenous malformation of gastrointestinal stromal tumor using hyperspectral and indocyanine green visualization techniques:A case report

BACKGROUND This case report demonstrates the simultaneous development of a gastrointestinal stromal tumour(GIST)with arteriovenous malformations(AVMs)within the jejunal mesentery.A 74-year-old male presented to the department of surgery at our institution with a one-month history of abdominal pain.Contrast-enhanced computed tomography revealed an AVM.During exploratory laparotomy,hyperspectral imaging(HSI)and indocyanine green(ICG)fluorescence were used to evaluate the extent of the tumour and determine the resection margins.Intraoperative imaging confirmed AVM,while histopathological evaluation showed an epithelioid,partially spindle cell GIST.CASE SUMMARY This is the first case reporting the use of HSI and ICG to image GIST intermingled with an AVM.The resection margins were planned using intraoperative analysis of additional optical data.Image-guided surgery enhances the clinician’s knowledge of tissue composition and facilitates tissue differentiation.CONCLUSION Since image-guided surgery is safe,this procedure should increase in popularity among the next generation of surgeons as it is associated with better postoperative outcomes.

A new projection model based robust 2D-3D registration method on Fourier-Mellin space for image guided intervention

An automatic method is proposed to solve the registration problem,which aligns a single 2D fluoroscopic image to a 3D image volume without demanding any additional media like calibration plate or user interactions.First,a mathematic projection model is designed which can reduce the influence of projection distortion on parameter optimization and improve the registration accuracy.Then,a two stage optimization method is proposed,which enables a robust registration in a wide parameter space.Furthermore,an automatic registration framework is proposed based on the FourierMellin robust image comparison descriptor.Experimental results show that the registration method has a high accuracy with average rotation error of 0.6 degree and average translation error of 1.4mm.

Navigated liver surgery:State of the art and future perspectives

Background:In recent years,the development of digital imaging technology has had a significant influence in liver surgery.The ability to obtain a 3-dimensional(3D)visualization of the liver anatomy has provided surgery with virtual reality of simulation 3D computer models,3D printing models and more recently holograms and augmented reality(when virtual reality knowledge is superimposed onto reality).In addition,the utilization of real-time fluorescent imaging techniques based on indocyanine green(ICG)uptake allows clinicians to precisely delineate the liver anatomy and/or tumors within the parenchyma,applying the knowledge obtained preoperatively through digital imaging.The combination of both has transformed the abstract thinking until now based on 2D imaging into a 3D preoperative conception(virtual reality),enhanced with real-time visualization of the fluorescent liver structures,effectively facilitating intraoperative navigated liver surgery(augmented reality).Data sources:A literature search was performed from inception until January 2021 in MEDLINE(Pub Med),Embase,Cochrane library and database for systematic reviews(CDSR),Google Scholar,and National Institute for Health and Clinical Excellence(NICE)databases.Results:Fifty-one pertinent articles were retrieved and included.The different types of digital imaging technologies and the real-time navigated liver surgery were estimated and compared.Conclusions:ICG fluorescent imaging techniques can contribute essentially to the real-time definition of liver segments;as a result,precise hepatic resection can be guided by the presence of fluorescence.Furthermore,3D models can help essentially to further advancing of precision in hepatic surgery by permitting estimation of liver volume and functional liver remnant,delineation of resection lines along the liver segments and evaluation of tumor margins.In liver transplantation and especially in living donor liver transplantation(LDLT),3D printed models of the donor’s liver and models of the recipient’s hilar anatomy can contribute further to improving the results.In particular,pediatric LDLT abdominal cavity models can help to manage the largest challenge of this procedure,namely large-for-size syndrome.

Clinical use of augmented reality,mixed reality,three-dimensionalnavigation and artificial intelligence in liver surgery

A precise knowledge of intra-parenchymal vascular and biliary architecture and the location of lesions in relation to the complex anatomy is indispensable to perform liver surgery.Therefore,virtual three-dimensional(3D)-reconstruction models from computed tomography/magnetic resonance imaging scans of the liver might be helpful for visualization.Augmented reality,mixed reality and 3Dnavigation could transfer such 3D-image data directly into the operation theater to support the surgeon.This review examines the literature about the clinical and intraoperative use of these image guidance techniques in liver surgery and provides the reader with the opportunity to learn about these techniques.Augmented reality and mixed reality have been shown to be feasible for the use in open and minimally invasive liver surgery.3D-navigation facilitated targeting of intraparenchymal lesions.The existing data is limited to small cohorts and description about technical details e.g.,accordance between the virtual 3D-model and the real liver anatomy.Randomized controlled trials regarding clinical data or oncological outcome are not available.Up to now there is no intraoperative application of artificial intelligence in liver surgery.The usability of all these sophisticated image guidance tools has still not reached the grade of immersion which would be necessary for a widespread use in the daily surgical routine.Although there are many challenges,augmented reality,mixed reality,3Dnavigation and artificial intelligence are emerging fields in hepato-biliary surgery.