The road to a successful surgery begins with proper and detailed surgical planning. The bottom of thorough surgical planning is based on individual image data. It is said that exceptions are a rule when it comes to anatomy. The anatomical structures of every person are unique and so it points out the necessity of an individual patient plan before any surgery. It doesn't matter whether the surgery is simple or complex, all surgeries must follow a standard operative procedure which should include detailed preoperative planning of the surgical procedure.
Despite the advancement in technology, preoperative imaging is still viewed in 2D cross-sectional CT or MRI images. These scans represent the 3D anatomical structures as a stack of 2D grayscale images. Surgeons only get to see these 2-dimensional images and with their prior anatomical knowledge, they have to reconstruct its 3D representation in their minds to understand the spatial arrangement of anatomical structures and their relations. This requires extensive training and is often found challenging even for experienced surgeons.
3D PDFs and 3D-printed models can somewhat alleviate the issues but also come with drawbacks. 3D prints are a time-consuming and costly procedure and 3D PDFs have the limitation of visualization of a 3D model on a standard screen depending on the surgeon’s mental ability to transfer images into 3D structures.
How Can Virtual Reality Help In Surgical Planning?
Virtual Reality is an excellent solution for surgeons who are always looking for newer technologies to improve the operative environment. VR is a promising new way to visualize three-dimensional anatomical structures for preoperative planning purposes. It enables the surgeon to analyze the anatomical complexity in a virtual world by providing the user with a stereoscopic 3D view of the model and enables the correct perception of depth. Such reproduction of a 3D anatomical model along with a high level of immersion and authenticity is not achievable with 2D imaging modalities. The surgeon gets a better spatial understanding of the anatomical structures and their relations with nearby structures. Not just that but it allows the surgeons to immerse themselves into an exclusive planning setting without distractions from the surroundings.
Elements Of The VR System :
1. Data Acquisition
The first step of developing a VR Surgery system is the acquisition of data. The Data should come from multiple imaging modalities (USG, CT, MRI, etc) which should be accurate and patient-specific
2. Fusion of Multi-modality data
To integrate all the Multidimensional properties of human organs, data acquired from different modalities need to be registered and fused to understand the different anatomical characteristics and their relations. For example how blood vessels and muscles are related.
3. Segmentation
Segmentation includes finding, extracting, and characterizing different features. It is an important step to extract important information from the overall patient data.
4. Registration
It is a process of setting up a reference frame between pre-surgical data with patient anatomy. Once a common reference frame is established, pre-surgical data can be used to visualize anatomical structures as an overlay.
5. Modeling
This is one of the crucial elements. It includes the development of deformable models in the organs that can be viewed as surface or volumetric models to provide real-time and realistic interactive surgical stimulation. Volumetric models allow you to see the interior of the organ (by cutting or incision). This can again be enhanced by adding visual realism by surface texture mapping. It can be achieved by using synthetic textures or photographs of the organs.
6. Interaction and Interface
The various data are presented to the surgeon via several displays. The surgeon navigates through the data and interacts with them and simultaneously receives feedback. The feedback can be visual, haptic, tactile, and auditory providing realism to surgery simulators
Advantages Of VR In Surgical Planning:
It can be summarized as
A better understanding of 3D anatomy
Better spatial understanding of anatomical relations
Fewer measurement errors than conventional cross-sectional viewing
Faster identification of surgical relevant anatomical variants
Provides a distraction-free environment for surgical planning with immersive technology
Immersive VR environment for shared or over-distance collaboration among surgeons
Decrease in the risks to the patient safety and improvement of the results
Companies Using Virtual Reality In Surgery
The potential of VR in healthcare is immense and many companies throughout the world have already begun working on the concept to change the future of surgery.
A few such companies are listed below:
ImmersiveTouch: Based in Chicago, ImmersiveTouch creates virtual 3D models using individual patient data
XR Health: Founded in 2016, this is the first company to start virtual clinics to provide remote consultation services across the United States
Proprio Vision: With computerized technology it allows surgeons to see through Obstruction via imaging tools which help to see the body in a new way and allows surgeons to collaborate on surgical plans.
OSSO VR: This company provides an interactive training platform with immersive VR and Haptic Feedback for orthopedic and spine surgery.
FundamentalVR: Based in London, UK, this company also provides an interactive training platform for surgeons to rehearse, practice, and improve their surgical techniques in a controlled environment that includes haptic elements for tactile feedback.
EchoPixel: The EchoPixel uses a multi-modal image data sets to create anatomical accurate patient-specific 3D images
Surgical Theater: With the use of precision VR, the company created a surgical rehearsal platform for neurosurgery.
Vicarious Surgical: This company combines virtual reality and surgical robots for minimally invasive surgical procedures.
Proximie: It provides a platform for the surgeon to find the lesion and explain the surgical procedure to the patient by using 3D models.
SentiAR: It allows the surgeon to view 3D images of organs in real-time during the surgery (intra-procedural).
References
Reitinger, Bernhard & Bornik, Alexander & Beichel, Reinhard & Schmalstieg, Dieter. (2006). Liver Surgery Planning Using Virtual Reality. IEEE computer graphics and applications. 26. 36-47. DOI: 10.1109/MCG.2006.131
Boedecker, C., Huettl, F., Saalfeld, P. et al. Using virtual 3D-models in surgical planning: workflow of an immersive virtual reality application in liver surgery. Langenbecks Arch Surg406, 911–915 (2021). DOI: 10.1007/s00423-021-02127-7
Timonen, T., Iso-Mustajärvi, M., Linder, P. et al. Virtual reality improves the accuracy of simulated preoperative planning in temporal bones: a feasibility and validation study. Eur Arch Otorhinolaryngol278, 2795–2806 (2021). DOI: 10.1007/s00405-020-06360-6
Amol Pednekar, Ioannis A. Kakadiaris. Applications of Virtual Reality In Surgery [Link]
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