Combined application of virtual surgery and 3D printing technology in postoperative reconstruction of head and neck cancers

Oral cavity cancer and its pre-treatment radiological evaluation: A pictorial overview

PURPOSE

Oral cavity cancer, primarily squamous cell carcinoma (SCC), is a prevalent malignancy globally, necessitating accurate clinical assessment and staging to enable effective treatment planning. Diagnosis requires biopsy and is followed by surgical resection and reconstruction as the primary therapeutic modality. Imaging plays a pivotal role during this process, aiding in the evaluation of tumour extent, nodal involvement and distant metastases. However, despite its value, both radiologists and clinicians must recognise its inherent limitations.

METHODS

This pictorial review article aims to illustrate the application of various imaging modalities in the pre-treatment evaluation of oral cavity SCC and highlights potential pitfalls. It underscores the importance of understanding the anatomical subsites of the oral cavity, the diverse patterns of spread tumours exhibit at each site, alongside the role of imaging in facilitating informed management strategies, while also acknowledging its limitations.

RESULTS

The review delves into fundamentals of current staging including nodal involvement, while, emphasising imaging strategies and potential limitations. Finally, it touches on the potential of novel radiomic techniques in characterising tumours and predicting treatment response.

CONCLUSIONS

Pre-treatment oral cavity cancer staging reflects an ongoing quest for enhanced diagnostic accuracy and prognostic prediction. Recognising the value of imaging alongside its limitations fosters a multidisciplinary approach to treatment planning, ultimately improving patient outcomes.

The Role of Imaging in Mandibular Reconstruction with Microvascular Surgery

Imaging plays a critical role in the diagnosis, staging, and management of segmental mandibular defects. Imaging allows mandibular defects to be classified which aids in microvascular free flap reconstruction. This review serves to complement the surgeon's clinical experience with image-based examples of mandibular pathology, defect classification systems, reconstruction options, treatment complications, and Virtual Surgical Planning.

Dual-stimuli responsive smart nanoprobe for precise diagnosis and synergistic multi-modalities therapy of superficial squamous cell carcinoma

BACKGROUND

Although the promising advancements of current therapeutic approaches is available for the squamous cell carcinoma (SCC) patients, the clinical treatment of SCC still faces many difficulties. The surgical irreparable disfigurement and the postoperative wound infection largely hamper the recovery, and the chemo/radiotherapy leads to toxic side effects.

RESULTS

Herein, a novel pH/Hyaluronidase (HAase) dual-stimuli triggered smart nanoprobe Fe^IIITA@HA has been designed through the biomineralization of Fe³⁺ and polyphenol tannic acid (TA) under the control of hyaluronic acid (HA) matrix. With the HA residues on the outer surface, Fe^IIITA@HA nanoprobes can specifically target the SCC cells through the over-expressed CD44, and accumulate in the carcinoma region after intravenously administration. The abundant HAase in carcinoma microenvironment will trigger the degradation of HA molecules, thereby exposing the Fe^IIITA complex. After ingesting by tumor cells via CD44 mediated endocytosis, the acidic lysosomal condition will further trigger the protonation of TA molecules, finally leading to the Fe³⁺ release of nanoprobe, and inducing a hybrid ferroptosis/apoptosis of tumor cells through peroxidase activity and glutathione depletion. In addition, Owing to the outstanding T₁ magnetic resonance imaging (MRI) performance and phototermal conversion efficiency of nanoprobes, the MRI-guided photothermal therapy (PTT) can be also combined to complement the Fe³⁺-induced cancer therapy. Meanwhile, it was also found that the nanoprobes can promote the recruitment of CD4⁺ and CD8⁺ T cells to inhibit the tumor growth through the cytokines secretion. In addition, the Fe^IIITA@HA nanoprobes can be eliminated from the body and no obvious adverse side effect can be found in histological analysis, which confirmed the biosafety of them.

CONCLUSION

The current Fe^IIITA@HA nanoprobe has huge potential in clinical translation in the field of precise diagnosis and intelligent synergistic therapy of superficial SCC. This strategy will promisingly avoid the surgical defects, and reduce the systemic side effect of traditional chemotherapy, paving a new way for the future SCC treatment.

A review on AI-based medical image computing in head and neck surgery

Head and neck surgery is a fine surgical procedure with a complex anatomical space, difficult operation and high risk. Medical image computing (MIC) that enables accurate and reliable preoperative planning is often needed to reduce the operational difficulty of surgery and to improve patient survival. At present, artificial intelligence, especially deep learning, has become an intense focus of research in MIC. In this study, the application of deep learning-based MIC in head and neck surgery is reviewed. Relevant literature was retrieved on the Web of Science database from January 2015 to May 2022, and some papers were selected for review from mainstream journals and conferences, such as IEEE Transactions on Medical Imaging, Medical Image Analysis, Physics in Medicine and Biology, Medical Physics, MICCAI, etc. Among them, 65 references are on automatic segmentation, 15 references on automatic landmark detection, and eight references on automatic registration. In the elaboration of the review, first, an overview of deep learning in MIC is presented. Then, the application of deep learning methods is systematically summarized according to the clinical needs, and generalized into segmentation, landmark detection and registration of head and neck medical images. In segmentation, it is mainly focused on the automatic segmentation of high-risk organs, head and neck tumors, skull structure and teeth, including the analysis of their advantages, differences and shortcomings. In landmark detection, the focus is mainly on the introduction of landmark detection in cephalometric and craniomaxillofacial images, and the analysis of their advantages and disadvantages. In registration, deep learning networks for multimodal image registration of the head and neck are presented. Finally, their shortcomings and future development directions are systematically discussed. The study aims to serve as a reference and guidance for researchers, engineers or doctors engaged in medical image analysis of head and neck surgery.

Digital surgery group versus traditional experience group in head and neck reconstruction: a retrospective controlled study to analyze clinical value and time-economic-social effect

Objective

Discuss the application value of digital surgical technology in the reconstruction of head and neck defects after tumor resection and comprehensively evaluate time-economic-benefit cost.

Methods

A retrospective analysis of head and neck cancer patients who underwent reconstructive operations in head and neck surgery at Sichuan Cancer Hospital from January 2015 to January 2021 was performed. According to the inclusion and exclusion criteria, a total of 52 cases were included, including 25 cases using digital surgery (DS) and 27 cases using the conventional surgery (CS). The clinical-pathological characteristics, postoperative complications, functional aesthetic evaluation indexes, and time-cost-satisfaction evaluation indexes between the two groups were compared and statistically analyzed. Typical cases using digital surgery were shared.

Results

Outcomes between the two groups were comparable, and there was no significant difference in survival outcome and follow-up time between the two groups (P > 0.05). There was no significant difference between the two groups in the defect size, pathological type, other major clinicopathological features, or operation-related indicators (P > 0.05). The incidence of titanium plate displacement, deformation or exposure, and facial scar deformity in the DS group was significantly lower than that in the CS group (P < 0.05). However, there was no significant difference in other short-term or long-term complications (P > 0.05). The incidence of dysphagia and eating disorders in the DS group was significantly reduced (P < 0.05). The speech and social functions were improved, but not significantly (P > 0.05). Meanwhile, there was no significant difference in the evaluation index of facial aesthetics in this study (P > 0.05). Furthermore, the total operation time, preparation time of bone flap from the donor site, osteotomy time, and reconstruction time in the DS group were significantly lower than those in the traditional operation group (P < 0.05), but the shaping time and vascular anastomosis time of recipient area could not be shortened (P > 0.05). In addition, there was no significant difference in total hospitalization days between the DS group and CS group (P > 0.05), but the time of ICU treatment and postoperative intravenous nutrition support in the DS group were shorter than those in the CS group (P < 0.05). In particular, the preoperative doctor-patient communication of the DS group was more effective, and the treatment satisfaction of patients including their families was higher after operation (P < 0.05).

Conclusion

Comprehensive application of digital surgical technology (CAD, CAM, VR, MA, etc.) in the reconstruction of the head and neck after tumor resection is feasible in clinical practice, which can not only improve the accuracy of repair, decrease some surgical complications, better preserve and improve patient’s diet and speech function, and reduce the operation and hospitalization time, but also increase the treatment cost. Furthermore, it is conducive to doctor-patient communication and improves patient satisfaction.

Effect Comparison of Assisted Surgery Simulated by Preoperative 3D Reconstruction and Minimally Invasive Surgery with the Assist of Knee Arthroscopy in the Treatment of Tibial Plateau Fracture under the Background of Intelligent Medicine

Objective

To explore the effect comparison of the assisted surgery simulated by preoperative 3D reconstruction and the minimally invasive surgery with the assist of knee arthroscopy in the treatment of tibial plateau fracture (TPF) under the background of intelligent medicine.

Methods

100 patients with TPF admitted to our hospital from January 2021 to January 2022 were selected as the study subjects. According to the order of admission, the patients were divided into the simulation group with 3D reconstruction (n = 50) and the auxiliary group with knee arthroscopy (n = 50), and the clinical indicators were compared between the two groups.

Results

There was no significant difference in any other clinical treatment indexes between the two groups except the surgery time (P > 0.05), and there was no significant difference in knee flexion ability, walking ability, and Rasmussen scores between the two groups after treatment (P > 0.05). However, compared with the auxiliary group with knee arthroscopy, the mean posterior slope angle and varus angle of the patients were significantly higher (P < 0.001), and the total incidence of complications was significantly lower (P < 0.05).

Conclusion

Based on the analysis under the background of intelligent medicine, it is found that the assisted surgery simulated by preoperative 3D reconstruction has a better effect and a higher safety, but they have the similar effects on improving the knee joint function of patients.

Secondary Mandible Reconstruction with Computer-Assisted-Surgical Simulation and Patient-Specific Pre-Bent Plates: The Algorithm of Virtual Planning and Limitations Revisited

Despite the known advantages of virtual surgical planning and three-dimensional (3D) printing, translation of virtual planning to actual operation is a challenge, especially in secondary mandibular reconstruction. Patients who underwent secondary microvascular mandibular reconstruction were retrospectively reviewed and categorized into three categories as follows: (i) defect not crossing the midline (category I); (ii) defects crossing the midline with availability of previous imaging data (category II) and; (iii) defects crossing the midline with unavailability of previous imaging data (category III). The resulting 3D printed models were used as an effective guide for plate bending during secondary reconstruction surgery. Accuracy of the reconstruction was evaluated by superimposing post-operative images over virtual plan. Out of eleven patients, five were category I, three were category II, and three were category III. The mean linear discrepancy between the planned and post-operative position was measured. A Mann-Whitney U test was conducted to compare mean discrepancy among the groups showed no significant difference between group I and group II (p > 0.05) whereas comparison of groups I and II with group III showed a significant difference (p < 0.01). The proposed algorithm for the generation of defect template for manual plate bending during secondary reconstruction of mandibular defects is valid with acceptable accuracy in various defect configurations.

Main Applications and Recent Research Progresses of Additive Manufacturing in Dentistry

In recent ten years, with the fast development of digital and engineering manufacturing technology, additive manufacturing has already been more and more widely used in the field of dentistry, from the first personalized surgical guides to the latest personalized restoration crowns and root implants. In particular, the bioprinting of teeth and tissue is of great potential to realize organ regeneration and finally improve the life quality. In this review paper, we firstly presented the workflow of additive manufacturing technology. Then, we summarized the main applications and recent research progresses of additive manufacturing in dentistry. Lastly, we sketched out some challenges and future directions of additive manufacturing technology in dentistry.

Procedure Increasing the Accuracy of Modelling and the Manufacturing of Surgical Templates with the Use of 3D Printing Techniques, Applied in Planning the Procedures of Reconstruction of the Mandible

The application of anatomical models and surgical templates in maxillofacial surgery allows, among other benefits, the increase of precision and the shortening of the operation time. Insufficiently precise anastomosis of the broken parts of the mandible may adversely affect the functioning of this organ. Applying the modern mechanical engineering methods, including computer-aided design methods (CAD), reverse engineering (RE), and rapid prototyping (RP), a procedure used to shorten the data processing time and increase the accuracy of modelling anatomical structures and the surgical templates with the use of 3D printing techniques was developed. The basis for developing and testing this procedure was the medical imaging data DICOM of patients treated at the Maxillofacial Surgery Clinic of the Fryderyk Chopin Provincial Clinical Hospital in Rzeszów. The patients were operated on because of malignant tumours of the floor of the oral cavity and the necrosis of the mandibular corpus, requiring an extensive resection of the soft tissues and resection of the mandible. Familiarity with and the implementation of the developed procedure allowed doctors to plan the operation precisely and prepare the surgical templates and tools in terms of the expected accuracy of the procedures. The models obtained based on this procedure shortened the operation time and increased the accuracy of performance, which accelerated the patient’s rehabilitation in the further course of events.

[Clinical analysis of oral and oropharyngeal cancer resection through oral approach]

Objective:To investigate the treatment effect of oral and oropharyngeal cancer resection through oral approach. Methods:Forty-eight patients who with oral and oropharyngeal cancer were admitted to the Department of Oral and Maxillofacial Surgery of the First Affiliated Hospital of Bengbu Medical College from January 2015 to January 2018, and all received preoperative chemotherapy, surgical treatment and postoperative radiotherapy. Among them, twenty-four patients who were treated with tumor resection through oral approach in the experimental group, the other twenty-four patients were treated with tumor resection by external approach in the control group. During the operation, both groups of patients were underwent selective neck lymph node dissection and free skin flap transplantation, and preventive radiotherapy were performed after the operation. The operation time, blood loss, and the positive rate of the wound around the wound and the undercut margin of the two groups were compared, and the survival rate of the skin flap was analyzed. The Kaplan-Meier method was used to calculate the survival rate after 3 years of regular follow-up after surgery, and the difference between the curves of the two surgical methods were compared by the Log-rank test, and the quality of life of patients in one year after operation was investigated and analyzed by Washington University students'quality questionnaire 4. Results:The operation time and blood loss of the experimental group were less than the control group, but the difference was not statistically significant（P>0.05）. The positive rate of frozen margins in both groups was 0. The flap survival rate was 95.8% in the experimental group and 91.7% in the control group, there was no significant difference between the two groups（P>0.05）, the overall flap survival rate in the two groups was 93.8%. The survival rates of the experimental group were 91.7%, 83.3%, and 74.8% in the 1-, 2-, and 3-years after surgery, and 87.5%, 79.2%, and 75.0% in the control group, there was no statistically significant difference between the experimental group and the control group（P>0.05）. The 1-year, 2-year and 3-year overall survival rates of the two groups were 93.1%, 83.7% and 78.8% respectively. Compared with the control group, the scores of appearance, activity, recreation, swallowing, chewing, speech and mood in the experimental group were significantly higher（P<0.05）. Conclusion:Resection of oral cancer tumors through the oral approach with free skin flap repair is in line with the concept of minimally invasive surgery, which improves the quality of life of patients after surgery while ensuring the survival rate, and is worthy of clinical application and promotion.

Establishing a point-of-care additive manufacturing workflow for clinical use

Additive manufacturing, or 3-Dimensional (3-D) Printing, is built with technology that utilizes layering techniques to build 3-D structures. Today, its use in medicine includes tissue and organ engineering, creation of prosthetics, the manufacturing of anatomical models for preoperative planning, education with high-fidelity simulations, and the production of surgical guides. Traditionally, these 3-D prints have been manufactured by commercial vendors. However, there are various limitations in the adaptability of these vendors to program-specific needs. Therefore, the implementation of a point-of-care in-house 3-D modeling and printing workflow that allows for customization of 3-D model production is desired. In this manuscript, we detail the process of additive manufacturing within the scope of medicine, focusing on the individual components to create a centralized in-house point-of-care manufacturing workflow. Finally, we highlight a myriad of clinical examples to demonstrate the impact that additive manufacturing brings to the field of medicine.

Imaging-based navigation technologies in head and neck surgery

PURPOSE OF REVIEW

Image guided navigation has had significant impact in head and neck surgery, and has been most prolific in endonasal surgeries. Although conventional image guidance involves static computed tomography (CT) images attained in the preoperative setting, the continual evolution of surgical navigation technologies is fast expanding to incorporate both real-time data and bioinformation that allows for improved precision in surgical guidance. With the rapid advances in technologies, this article allows for a timely review of the current and developing techniques in surgical navigation for head and neck surgery.

RECENT FINDINGS

Current advances for cross-sectional-based image-guided surgery include fusion of CT with other imaging modalities (e.g., magnetic resonance imaging and positron emission tomography) as well as the uptake in intraoperative real-time 'on the table' imaging (e.g., cone-beam CT). These advances, together with the integration of virtual/augmented reality, enable potential enhancements in surgical navigation. In addition to the advances in radiological imaging, the development of optical modalities such as fluorescence and spectroscopy techniques further allows the assimilation of biological data to improve navigation particularly for head and neck surgery.

SUMMARY

The steady development of radiological and optical imaging techniques shows great promise in changing the paradigm of head and neck surgery.

Retroperitoneal teratoma resection assisted by 3-dimensional visualization and virtual reality: A case report

BACKGROUND

Primary retroperitoneal tumor is a rare type of tumor with insidious onset, large tumor size at the time of diagnosis, and often extensive involvement of surrounding tissues and blood vessels in the retroperitoneum. Surgery for primary retroperitoneal tumors is technically challenging. Preoperative imaging evaluation is critical for the selection of the optimal surgical approach and can influence complete resection and recurrence rates. Three-dimensional model reconstruction combined with virtual reality is useful for preoperative assessment.

CASE SUMMARY

A 17-year-old female patient was admitted for abdominal pain lasting for half a year that had been worsening for half a month. Abdominopelvic enhanced helical computed tomography revealed a retroperitoneal space-occupying lesion about 11.3 cm × 9.1 cm in size, with well-defined borders in the upper left quadrant of the abdomen. The lesion compressed the left renal artery and vein resulting in vascular displacement and deformation. A multidisciplinary team decided on the optimal treatment approach. Preoperative three-dimensional visualization and virtual reality technology were used to assess and simulate the surgical procedure. Then, retroperitoneal tumor resection along with renal artery reconstruction was decided as the treatment. Complete resection of the retroperitoneal tumor was performed. Stable blood flow was established after renal artery reconstruction. The tumor was diagnosed as mature cystic teratoma (retroperitoneal tumor) by postoperative pathologic analysis. The patient, who recovered well, was discharged after 2 wk and maintains regular follow-ups.

CONCLUSION

A combination of three-dimensional reconstruction and virtual reality technology before surgery improves the rate of complete resection of retroperitoneal teratoma.

Robotics in Pediatric Otolaryngology-Head and Neck Surgery and Advanced Surgical Planning

Robotic surgery has been shown to be feasible and successful in several areas of pediatric head and neck surgery. However, adoption has been limited. Robotic surgery may be better integrated into practice with advanced preoperative surgical planning and the design of new robotic platforms with instrumentation specific for the application. With continued investigations, computer-aided surgical planning techniques including three-dimensional printing, virtual reality, multiobjective cost function for optimization of approach, mirror image overlay, and flexible robotic instruments may demonstrate value and utility over current practice.