Image-Guided Surgery Influences Perioperative Morbidity from Endoscopic Sinus Surgery

Surgical Navigation in the Anterior Skull Base Using 3-Dimensional Endoscopy and Surface Reconstruction

Importance

Image guidance is an important adjunct for endoscopic sinus and skull base surgery. However, current systems require bulky external tracking equipment, and their use can interrupt efficient surgical workflow.

Objective

To evaluate a trackerless surgical navigation system using 3-dimensional (3D) endoscopy and simultaneous localization and mapping (SLAM) algorithms in the anterior skull base.

Design, Setting, and Participants

This interventional deceased donor cohort study and retrospective clinical case study was conducted at a tertiary academic medical center with human deceased donor specimens and a patient with anterior skull base pathology.

Exposures

Participants underwent endoscopic endonasal transsphenoidal dissection and surface model reconstruction from stereoscopic video with registration to volumetric models segmented from computed tomography (CT) and magnetic resonance imaging.

Main Outcomes and Measures

To assess the fidelity of surface model reconstruction and accuracy of surgical navigation and surface-CT model coregistration, 3 metrics were calculated: reconstruction error, registration error, and localization error.

Results

In deceased donor models (n = 9), high-fidelity surface models of the posterior wall of the sphenoid sinus were reconstructed from stereoscopic video and coregistered to corresponding volumetric CT models. The mean (SD; range) reconstruction, registration, and localization errors were 0.60 (0.24; 0.36-0.93), 1.11 (0.49; 0.71-1.56) and 1.01 (0.17; 0.78-1.25) mm, respectively. In a clinical case study of a patient who underwent a 3D endoscopic endonasal transsphenoidal resection of a tubercular meningioma, a high-fidelity surface model of the posterior wall of the sphenoid was reconstructed from intraoperative stereoscopic video and coregistered to a volumetric preoperative fused CT magnetic resonance imaging model with a root-mean-square error of 1.38 mm.

Conclusions and Relevance

The results of this study suggest that SLAM algorithm-based endoscopic endonasal surgery navigation is a novel, accurate, and trackerless approach to surgical navigation that uses 3D endoscopy and SLAM-based algorithms in lieu of conventional optical or electromagnetic tracking. While multiple challenges remain before clinical readiness, a SLAM algorithm-based endoscopic endonasal surgery navigation system has the potential to improve surgical efficiency, economy of motion, and safety.

Endoscopic Endonasal Trans-Sphenoidal Minimally Invasive Pituitary Surgery with Image Guided Navigation System (Igns): Learning Experience of Ent Surgeon: First Author

Introduction- Endoscopic minimally invasive pituitary surgery (MIPS) is advantageous over microscopic technique, as it provides superior close up, wide angle view of surgical target area. Image guided navigation system (IGNS) guides the surgeon to localize the lesion. In the present study we analyzed the Image Guided Surgical procedure and outcome of Endoscopic minimally invasive pituitary surgery and shared our experiences regarding disease clearance.

MATERIALS AND METHODS

During the period of April 2015 to August 2022 a total 104 patients, diagnosed with pituitary adenoma underwent surgery and further followed up in a multidisciplinary team approach in a tertiary care hospital of Kolkata, India. The data obtained were reviewed statistically to satisfy the study objectives.

RESULTS

Total 104 operations were done on 98 patients and total cases taken for calculation and analysis was 98, which consist of 11 microadenomas, 81 macroadenomas. Among 35 patients with normal preoperative hormonal assay, one patient developed postoperative hypopituitarism. Among 6 patients with preoperative hypopituitarism 4 patients (66.6%) recovered after surgery. Overall, 85 cases had total disease clearance as detected on post-operative MRI. In functioning pituitary adenoma (FPA) clinical and endocrinological improvement occurred after primary surgery in 85.36% (n = 35) and after revision surgery it was 84.44% (n = 38). Macroadenomas, giant adenomas were found to have statistically significant higher risk of incomplete disease clearance but large adenomas do not have statistically higher risk of incomplete clearance.

CONCLUSION

IGNS requires extra time for setup, but with proper registration of tracker instruments it adds precision to the surgery. IGNS supplements endoscopic visualization with localization of target lesion by real time stereotactic feedback using preset preoperative imaging data, thus increasing accuracy, safety and effectiveness of minimally invasive surgery.

Otolaryngology Considerations of Pituitary Surgery: What an Endocrinologist Should Know

Endoscopic endonasal skull base surgery is the preferred surgical approach for the management of pituitary adenomas. Perioperative management of pituitary lesions requires multidisciplinary care and typically includes a dual surgeon team consisting of a neurosurgeon and an otolaryngologist. The involvement of the otolaryngologist allows for a safe surgical approach with excellent intraoperative visualization of the tumor to enable an effective resection of the tumor by the neurosurgeon. Detection and treatment of sinonasal pathology is essential prior to surgery. Patients may experience sinonasal complaints following endoscopic transsphenoidal surgery, although this is typically temporary. Sinonasal care in the postoperative period can expedite recovery to baseline. Here we discuss the perioperative factors of endoscopic pituitary surgery that endocrinologists should be aware of, ranging from preoperative patient selection and optimization to postoperative care, with a particular emphasis on anatomic and surgical factors.

Skull-Base Surgery—A Narrative Review on Current Approaches and Future Developments in Surgical Navigation

Surgical navigation technology combines patient imaging studies with intraoperative real-time data to improve surgical precision and patient outcomes. The navigation workflow can also include preoperative planning, which can reliably simulate the intended resection and reconstruction. The advantage of this approach in skull-base surgery is that it guides access into a complex three-dimensional area and orients tumors intraoperatively with regard to critical structures, such as the orbit, carotid artery and brain. This enhances a surgeon’s capabilities to preserve normal anatomy while resecting tumors with adequate margins. The aim of this narrative review is to outline the state of the art and the future directions of surgical navigation in the skull base, focusing on the advantages and pitfalls of this technique. We will also present our group experience in this field, within the frame of the current research trends.

Adverse Events Associated With Image-Guided Sinus Navigation in Endoscopic Sinus Surgery: A MAUDE Database Analysis

OBJECTIVE

The utilization of image-guided navigation during endoscopic sinus surgery (ESS) has increased significantly since its introduction. However, the most common associated complications are still unknown. This study describes and analyzes adverse events related to image-guided ESS.

STUDY DESIGN

Cross-sectional analysis.

SETTING

The Food and Drug Administration's 2018-2022 MAUDE database (Manufacturer and User Facility Device Experience).

METHODS

The MAUDE database was searched for all reports on adverse events involving sinus navigation systems used in ESS from 2018 to 2022. Reported events were reviewed and categorized.

RESULTS

During the study period, there were 1857 adverse events from 1565 reports, which were divided into device-related (n = 1834, 98.8%) and patient-related (n = 23, 1.2%) complications. The most common device-related complications were nonfunctionality of the system (n = 512, 27.9%), device imprecision (n = 427, 23.3%), and device sensing problems (n = 277, 15.1%). The most common patient-related complications were cerebrospinal fluid (CSF) leak (n = 14, 60.9%), intracranial injury (n = 4, 17.4%), and bleeding/hemorrhage (n = 3, 13.1%). Imprecision was associated with increased risk of navigation abortion by the surgeon (odds ratio, 1.50 [95% CI, 1.38-1.65]; P < .001) and increased risk of CSF leak (odds ratio, 16.5 [95% CI, 3.66-74.0]; P < .001) as compared with other device-related complications.

CONCLUSIONS

The most commonly reported device- and patient-related adverse events associated with image-guided sinus navigation systems were device nonfunction, imprecision, device sensing difficulties, and CSF leak. When imprecise navigation occurred, there was an increased likelihood of CSF leak and navigation abortion by the surgeon. Health care providers should be mindful of these possible complications when electing to use image-guided sinus navigation during ESS.

Clinical and economic benefits of image-guided system in functional endoscopicsinus surgery: a retrospective chart review study in China

BACKGROUND

Image-guided system (IGS) has been gradually applied in the field of rhinology, making functional endoscopic sinus surgery (FESS) a truly minimally invasive and precise surgery. This study was based on real-world data from China hospitals and aimed to evaluate the clinical and economic benefits of the IGS navigation system in FESS.

METHODS

This was a two-center retrospective chart review of patients with chronic rhinosinusitis who underwent FESS, including open frontal sinus between July 1, 2018 and December 31, 2019 in China. The intervention group consisted of 100 patients who underwent FESS with the IGS navigation system (IGS group), and the control group consisted of 100 patients who underwent conventional FESS (Non-IGS group). Data were collected from surgical notes and hospital medical records. The primary endpoints for clinical effectiveness and safety were avoid rehospitalization due to bleeding, avoid reoperation due to bleeding, and avoid reoperation due to recurrence.

RESULTS

There were no cases of rehospitalization due to bleeding, reoperation due to bleeding, and reoperation due to recurrence in the IGS group, with an avoidance rate of 100%. In the non-IGS group, there were four cases of rehospitalization and reoperation due to bleeding, with an avoidance rate 96.00% (P = 0.121). No cases of reoperation due to recurrence were in the non-IGS group. The total hospitalization cost was 17,391.51 CNY in the IGS group and 17,742.41 CNY in the non-IGS group per patient, with no statistical difference between the two groups (P = 0.715). Compared with the non-IGS group, the IGS group had an overall cost saving of 350.90 CNY per patient. Although the procedure-related medical costs of IGS group were increased by 1,286.12 CNY compared with the non-IGS group, this was more than offset by other costs.

CONCLUSION

The results of the study indicated that the IGS may avoid occurrence of rehospitalization and reoperation due to postoperative bleeding. Although the use of navigation technology increased the cost of surgery, its clinical effectiveness brought other medical cost savings, resulting in no significant difference in the overall cost of navigation surgery compared to conventional surgery. The IGS should be considered cost-effectiveness in the treatment of FESS.

Improving situation recognition using endoscopic videos and navigation information for endoscopic sinus surgery

PURPOSE

Endoscopic sinus surgery (ESS) is widely used to treat chronic sinusitis. However, it involves the use of surgical instruments in a narrow surgical field in close proximity to vital organs, such as the brain and eyes. Thus, an advanced level of surgical skill is expected of surgeons performing this surgery. In a previous study, endoscopic images and surgical navigation information were used to develop an automatic situation recognition method in ESS. In this study, we aimed to develop a more accurate automatic surgical situation recognition method for ESS by improving the method proposed in our previous study and adding post-processing to remove incorrect recognition.

METHOD

We examined the training model parameters and the number of long short-term memory (LSTM) units, modified the input data augmentation method, and added post-processing. We also evaluated the modified method using clinical data.

RESULT

The proposed improvements improved the overall scene recognition accuracy compared with the previous study. However, phase recognition did not exhibit significant improvement. In addition, the application of the one-dimensional median filter significantly reduced short-time false recognition compared with the time series results. Furthermore, post-processing was required to set constraints on the transition of the scene to further improve recognition accuracy.

CONCLUSION

We suggested that the scene recognition could be improved by considering the model parameter, adding the one-dimensional filter and post-processing. However, the scene recognition accuracy remained unsatisfactory. Thus, a more accurate scene recognition and appropriate post-processing method is required.

Impact of Prolonged Operative Time on Complications Following Endoscopic Sinonasal Surgery

OBJECTIVE

To determine how prolonged operative time (POT) impacts 30-day outcomes in patients undergoing endoscopic sinonasal surgery (ESNS).

STUDY DESIGN

Retrospective study.

METHODS

Data from patients who underwent ESNS (nonsinus, sinus, and extended sinus) between 2005 to 2018 were collected from the American College of Surgeons National Surgical Quality Improvement database. Univariate and multivariate analyses were performed to evaluate the effect of POT on postoperative outcomes.

RESULTS

Among 1,994 ESNS cases, 495 nonsinus procedures, 1,191 sinus procedures, and 308 extended sinus procedures were identified. Median OT was 90 minutes (interquartile range [IQR], 51-165 minutes) for nonsinus procedures, 113 minutes (IQR, 66-189 minutes) for sinus procedures, and 187 minutes (IQR, 137-251 minutes) for extended sinus procedures. Other than older age (P = .008), POT was not significantly associated with baseline demographics and comorbidities for patients undergoing non-sinus procedures. Older age (P < .001), White and Black race (P < .001), ASA physical classifications III or IV (P < .001), and several preoperative comorbidities, including obesity (P = .045), and hypertension (P < .001) were associated with POT for sinus procedures. Older age (P = .030), male sex (P = .010), and lower body mass index (P = .004) were associated with POT for extended sinus procedures. After risk-adjustment, POT was independently associated with prolonged hospital stay (LOS) for all procedure categories, and associated with overall surgical complications and postoperative bleeding for sinus and extended sinus procedures specifically.

CONCLUSION

POT is independently associated with several adverse outcomes following ESNS, including prolonged LOS, overall surgical complications, and bleeding. Preoperative planning should include optimizing modifiable patient risk factors for POT and identifying surgeon-specific factors to enhance surgical efficiency.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:51-58, 2023.

Image Guided Endoscopic Sinus Surgery: First Experience from Kashmir Valley

Image guidance is best suited to paranasal sinus surgeries as these demand a high degree of anatomical precision because of close proximity to orbit and cranial cavity which at times is challenging in patients with frequent anatomical variations. This study is aimed to describe our first experience of using image guided endoscopic sinus surgery in Kashmir valley in terms of real time correlation between the operative field and the preoperative imaging; to evaluate its utility in disease clearance and to evaluate patient reported outcome measures using (pre and post-op) VAS, SNOT-22, Lund Mackey endoscopic and radiological scores. This prospective observational study was conducted from September 2016 to August 2018. Patients with the specific inclusion and exclusion criteria were operated using image guidance system. Pre and post operative SNOT-22, VAS, Lund Mackey endoscopic and radiological scoring were compared. Operative time, Instrument accuracy and complications were noted. Out of twenty cases enrolled in this study majority (14) patients (70%) were cases of uncomplicated chronic rhinosinusitis with nasal polyposis. Mean number of sinuses operated were 7.8 ± 2.14. Set up time for installing navigation system in first 10 cases was on an average 17 ± 1.67 min and in second 10 cases it was 12 ± 1.42 min. Mean operative time recorded was 112 ± 17.32 min. Accuracy of our system was 1.25 ± 0.73 mm (0.50-1.80) and average blood loss was 100 ± 23.54 ml. There was statistically significant reduction in postoperative VAS score, SNOT-22 score, Lund Mackey endoscopic and radiological scoring. Revision FESS was done in 12 cases and most common intraoperative absent nasal landmark was middle turbinate in these cases. No orbital or intracranial complication was seen. Minor complications were seen. Image guided surgery is a valuable tool worth use in difficult and revision cases. It makes the surgeon comfortable and saves patient from any major complication.

Image-Guided Surgical Device Failures in Functional Endoscopic Sinus Surgery: A MAUDE Analysis

OBJECTIVE

Image-guided surgery (IGS) devices have become widely used for anatomic localization during functional endoscopic sinus surgery (FESS). However, there are no studies that analyze the post-market complications associated with IGS device use during FESS. The objective of this study was to better characterize post-market complications associated with the use of IGS devices during sinus surgery.

METHODS

The US Food and Drug Administration's Manufacturer and User Facility Device Experience database was queried for event reports associated with neurological stereotaxic devices utilized in IGS between the dates of January 1, 2016 and December 31, 2020. Medical device reports that were analyzed for this study pertained strictly to FESS.

RESULTS

There were 1873 reports involving IGS devices for FESS included in this study. Fifty-five reports involved adverse events to patients (2.9%) and 1818 (97.1%) involved device malfunctions. Of the adverse events to patients, the most common included cerebrospinal fluid leakage (45.6%), tissue damage (12.7%), and nervous system injury (3.6%). The most commonly reported device malfunction was imprecision (21.1%).

CONCLUSION

IGS devices are widely utilized in FESS. Of the medical device reports between 2016 and 2020, less than 3% resulted in adverse events. Further studies of the infrequent post-market complications of IGS devices used in FESS can help guide surgeons on the risks of their clinical use.

LEVEL OF EVIDENCE

4-Retrospective database survey without controls Laryngoscope, 2022.

Image guidance system use amongst Canadian otolaryngologists: a nationwide survey

Background

The use of image guidance systems has gained widespread acceptance as an adjunctive tool for endoscopic sinus surgery. However, the accessibility and usage of this technology is variable across hospitals in Canada.

Study objective

The aim of this study is to investigate the availability, usage, and related issues surrounding the use of image guidance systems in endoscopic sinus surgery across Canadian otolaryngology practice settings.

Methods

An online survey was electronically distributed to practicing otolaryngologists across Canada. The survey contained 27 questions pertaining to the availability, usage, barriers and overall experience of image guidance systems.

Results

The survey was electronically sent to a total of 654 Canadian otolaryngologists of which 158 responded (response rate 24.2%). Image guidance was available to 56.3% of respondents. Of the respondents without access to IGS, 85.5% indicated they would use it if it was available. Financial (capital cost) was identified as the most important barrier in obtaining IGS by 76.3% of respondents.

Conclusion

Over half of Canadian otolaryngologists have access to IGS with over 85% of those without access interested in using it if it was made available. A multitude of different factors contribute to this disparity. We hope that the results of this study will help support Canadian otolaryngologists to access IGS.

Graphical Abstract

Carotid artery injury in endoscopic endonasal surgery: Risk factors, prevention, and management

Objective

Endoscopic approaches for sinus and skull base surgery are increasing in popularity. The objective of this narrative review is to characterize risk factors for internal carotid artery injury in endoscopic endonasal surgery (EES), highlight preventative measures, and illustrate key management principles.

Data Sources

Comprehensive literature review.

Methods

Relevant literature was reviewed using PubMed/MEDLINE.

Results

Carotid artery injury in EES is rare, with most studies reporting an incidence below 0.1%. Anatomic aberrancies, wide dissection margins, as well as specific provider and hospital factors, may increase the risk of injury. Multidisciplinary teams, comprehensive preoperative imaging, patient risk assessment, and formal training in vascular emergencies may reduce the risk. Management protocols should emphasize proper visualization of the injury site, fluid replacement, rapid packing, angiography, and endovascular techniques to achieve hemostasis.

Conclusions

While EES is a relatively safe procedure, carotid artery injury is a devastating complication that warrants full consideration in surgical planning. Important preventative measures include identifying patients with notable risk factors and obtaining preoperative imaging. Multidisciplinary teams and management protocols are ultimately necessary to reduce morbidity and mortality.

Internal carotid artery (ICA) injury is a rare complication of endoscopic endonasal surgery.

Risk factors for ICA injury may include vascular anatomic variants, invasive pathology, and prior radiation therapy.

Surgical team preparation and experience are key to successful management of operative complications.

A review of the revisions and complications management procedure in sinus surgery

One of the most standard and least invasive surgical procedures that could be applied mostly for the treatment of inflammation of the paranasal sinuses is endonasal endoscopic sinus surgery. The main objective of this study is to assess the available strategies for avoiding, diagnosis and also dealing with various kinds of potential complications of sinus disorders as well as the symptoms which specify the need for revision endoscopic sinus surgery mainly for the treatment of chronic rhinosinusitis. Based on the objectives of this study, the studies were categorized within four main groups; sinus disorders, diagnosis, management, and treatment. In this regard, wide research has been done in various scientific databases of PubMed, EMBASE, Europe PMC, HubMed, MEDLINE, Scientific Information Database (SID) and Google Scholar. From a total of 315 founded records, the final number of 91 records were reviewed. The rate of complication associated with endoscopic sinus surgery is not much and the improvement of surgical technology and experience could decrease its side effects. Performing immediate extensive surgery among patients who have inflammatory sinonasal disease could modify long-term consequences. Applying endoscopic sinus surgery could yield the most appropriate positive outcomes. For achieving the most suitable surgical consequences, the surgeon should be adequately qualified in diagnosis and facing with any possible complications during the operation in addition to cases with complex and revision problems.

A systematic review of common landmarks in navigated endoscopic sinus surgery (NESS)

BACKGROUND

Navigation brought about a tremendous improvement in functional endoscopic sinus surgery (FESS). When upgraded accordingly, FESS becomes navigated endoscopic sinus surgery (NESS). Indications for intraoperative use of navigation can be broadened to almost any FESS case. NESS in advanced sinus surgery is currently still not used routinely and requires systematic practice guidelines.

PURPOSE

The purpose of this paper is to report on commonly identified landmarks while performing advanced NESS according to evidence-based medicine (EBM) principles.

MATERIAL AND METHODS

This review paper has been assembled following PRISMA guidelines. A PubMed and Scopus (EMBASE) search on anatomical landmarks in functional endoscopic and navigated sinus surgery resulted in 47 results. Of these, only 14 (29.8%) contained original data, constituting the synthesis of best-quality available evidence.

RESULTS

Anatomical landmarks are considered to be the most important points of orientation for optimal use of navigation systems during FESS surgery. The most commonly identified significant landmarks are as follows: (1) Maxillary sinus ostium; (2) Orbital wall; (3) Frontal recess; (4) Skull base; (5) Ground lamella; (6) Fovea posterior; (7) Sphenoid sinus ostium. Conclusions: Establishing common landmarks are essential in performing NESS. This is true for advanced and novice surgeons alike and offers a possibility to use navigation systems systematically, taking advantage of all the benefits of endoscopic navigated surgery.

The utility of augmented reality in lateral skull base surgery: A preliminary report

OBJECTIVE

To discuss the utility of augmented reality in lateral skull base surgery.

PATIENTS

Those undergoing lateral skull base surgery at our institution.

INTERVENTION(S)

Cerebellopontine angle tumor resection using an augmented reality interface.

MAIN OUTCOME MEASURE(S)

Ease of use, utility of, and future directions of augmented reality in lateral skull base surgery.

RESULTS

Anecdotally we have found an augmented reality interface helpful in simulating cerebellopontine angle tumor resection as well as assisting in planning the incision and craniotomy.

CONCLUSIONS

Augmented reality has the potential to be a useful adjunct in lateral skull base surgery, but more study is needed with large series.

Image-guided surgery in otolaryngology: A review of current applications and future directions in head and neck surgery

Image-guided surgery (IGS) has become a widely adopted technology in otolaryngology. Since its introduction nearly three decades ago, IGS technology has developed rapidly and improved real-time intraoperative visualization for a diverse array of clinical indications. As usability, accessibility, and clinical experiences with IGS increase, its potential applications as an adjunct in many surgical procedures continue to expand. Here, we describe the basic components of IGS and review both the current state and future directions of IGS in otolaryngology, with attention to current challenges to its application in surgery of the nonrigid upper aerodigestive tract.

Three-dimensional virtual planning for nodule resection in solid organs: A systematic review and meta-analysis

OBJECTIVES

To systematically review the effects of 3D-imaging virtual planning for nodule resection in the following solid organs: lung, liver, and kidney.

METHODS

MEDLINE, EMBASE, and Cochrane Library were searched through September 31, 2020 to include randomized and non-randomized controlled studies that compared outcomes of surgical resection of lung, liver, or kidney nodule resection with and without 3D virtual planning with computed tomography. From each article, the mean operation time (OT), mean estimated blood loss (EBL), mean postoperative hospital stay (POHS), and the number of postoperative events (POE) were extracted. The effect size (ES) of 3D virtual planning vs. non-3D planning was extracted from each study to calculate the pooled measurements for continuous variables (OT, EBL, POHS). Data were pooled using a random-effects model.

RESULTS

The literature search yielded 2397 studies and 10 met the inclusion criteria with a total of 897 patients. There was a significant difference in OT between groups with a moderate ES favoring the 3D group (ES,-0.56; 95%CI: 0.91,-0.29; I² = 83.1%; p < .001). Regarding EBL, there was a significant difference between 3D and non-3D with a small ES favoring IGS (ES,-0.18; 95%CI: 0.33,-0.02; I² = 22.5%; p = .0236). There was no difference between the 3D and non-3D groups for both POHS (POHS ES,-0.15; 95%CI: 0.39,0.10; I² = 37.0%; p = .174) and POE (POE odds ratio (OR),0.80; 95%CI:0.54,1.19; I² = 0.0%; p = .0.973).

CONCLUSIONS

3D-imaging planning for surgical resection of lung, kidney, and liver nodules could reduce OT and EBL with no effects on immediate POHS and POE. Improvements in these perioperative variables could improve medium and long-term postoperative clinical outcomes.

International consensus statement on allergy and rhinology: rhinosinusitis 2021

I.

EXECUTIVE SUMMARY

BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document.

METHODS

ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary.

RESULTS

ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided.

CONCLUSION

This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.

Assessment of Factors Associated With Internal Carotid Injury in Expanded Endoscopic Endonasal Skull Base Surgery

Importance

Injury to the internal carotid artery (ICA) during endoscopic endonasal skull base surgery does not typically occur as an isolated circumstance but often is the result of multiple factors.

Objective

To assess the factors associated with ICA injury in an effort to reduce its occurrence.

Design, Setting, and Participants

This quality improvement study used a multicenter root cause analysis of ICA injuries sustained during endoscopic endonasal skull base surgery performed at 11 tertiary care centers across 4 continents (North America, South America, Europe, and Asia) from January 1, 1993, to December 31, 2018. A fishbone model was built to facilitate the root cause analysis. Patients who underwent an expanded endoscopic endonasal approach that carried a substantial potential risk of an ICA injury were included in the analysis. A questionnaire was completed by surgeons at the centers to assess relevant human, patient, process, technique, instrument, and environmental factors associated with the injury.

Main Outcomes and Measures

Root cause analysis of demographic, human, patient, process, technique, instrument, and environmental factors as well as mortality and morbidity data.

Results

Twenty-eight cases of ICA injury occurred during 7160 expanded endoscopic endonasal approach procedures (incidence of 0.4%). The mean age of the patients was 49 years, with a female to male predominance ratio of 1.8:1 (18 women to 10 men). Anatomical (23 [82%]), pathological (15 [54%]), and surgical resection (26 [93%]) factors were most frequently reported. The surgeon's mental or physical well-being was reported as inadequate in 4 cases (14%). Suboptimal imaging was reported in 6 cases (21%). The surgeon's experience level was not associated with ICA injury. The ICA injury was associated with use of powered or sharp instruments in 20 cases (71%), and use of new instruments or technology in 7 cases (25%). Two patients (7%) died in the operating room, and 3 (11%) were alive with neurological deficits. Overall, patient-related factors were the most frequently reported risk factors (in 27 of 28 cases [96%]). Factors associated with ICA injury catalyzed a list of preventive recommendations.

Conclusions and Relevance

This study found that human factors were associated with intraoperative ICA injuries; however, they were usually accompanied by other deficiencies. These findings suggest that identifying risk factors is crucial for preventing such injuries. Preoperative planning and minimizing the potential for ICA injury also appear to be essential.

Navigation-assisted endoscopic surgery of lacrimal sac tumor

Tumor of lacrimal sac invading into orbit has to be removed carefully to avoid injuring the eyeball, optic nerve, and extraocular muscles. Transnasal endoscopic-assisted tumor excision is a method to remove the tumor from the nasal cavity through the lacrimal sac to the orbit in one procedure. A 55-year-old female patient with thyroid carcinoma removed more than 10 years ago. She recently had a swollen submandibular lymph node enlargement, which was pathologically diagnosed as metastatic carcinoma. Follow-up investigation showed a tumor in the ipsilateral lacrimal sac with invasion into adjacent orbit and nasal cavity. The tumor was removed through image-guided surgery (IGS), navigation-assisted transnasal endoscopic-assisted excision. The tumor was removed as much as possible. The eyeball, extraocular muscles, and optic nerve were not injured in the surgery. Postoperative swelling was minimal with mild nasal hemorrhage. No ecchymosis and conjunctiva chemosis and eyelid swelling was noticed. Ocular motility was full without diplopia. Although exenteration and partial maxillectomy were suggested after pathological result showed a carcinoma of lacrimal sac, patient did not want these extensive surgery immediately. On patient request to reserve the eyeball function, navigation-assisted transnasal endoscopic excision is a safe and efficient method for the preliminary surgery. This case of orbital tumor excision using endoscope and IGS navigation system is the first case by Taiwan ophthalmologists.

Augmented reality-enhanced navigation in endoscopic sinus surgery: A prospective, randomized, controlled clinical trial

OBJECTIVE

Endoscopic sinus surgery represents the gold standard for surgical treatment of chronic sinus diseases. Thereby, navigation systems can be of distinct use. In our study, we tested the recently developed KARL STORZ NAV1 SinusTracker navigation software that incorporates elements of augmented reality (AR) to provide a better preoperative planning and guidance during the surgical procedure.

METHODS

One hundred patients with chronic sinus disease were operated on using either a conventional navigation software (n = 52, non-AR, control group) or a navigation software incorporating AR elements (n = 48, AR, intervention group). Incidence of postoperative complications, duration of surgery, surgeon-reported benefit from the navigation system and patient-reported postoperative rehabilitation were assessed.

RESULTS

The surgeons reported a higher benefit during surgery, used the navigation system for more surgical steps and spent longer time with preoperative image analysis when using the AR system as compared with the non-AR system. No significant differences were seen in terms of postoperative complications, target registration error, operation time and postoperative rehabilitation.

CONCLUSION

The AR enhanced navigation software shows a high acceptance by sinus surgeons in different stages of surgical training and offers potential benefits during surgery without affecting the duration of the operation or the incidence of postoperative complications.

LEVEL OF EVIDENCE

1b.

The Frontal Sinus and Frontal Recess: Anatomical, Radiological and Surgical Concepts

Introduction  The frontal sinus (FS) is the most complex of the paranasal sinuses due to its location, anatomical variations and multiple clinical presentations. The surgical management of the FS and of the frontal recess (FR) is technically challenging, and a complete understanding of its anatomy, radiology, main diseases and surgical techniques is crucial to achieve therapeutic success. Objectives  To review the FS and FR anatomy, radiology, and surgical techniques. Data Synthesis  The FS features a variety of anatomical, volumetric and dimensional characteristics. From the endoscopic point of view, the FR is the point of greatest narrowing and, to have access to this region, one must know the anatomical limits and the ethmoid cells that are located around the FR and very often block the sinus drainage. Benign diseases such as chronic rhinosinusitis (CRS), mucocele and osteomas are the main pathologies found in the FS; however, there is a wide variety of malignant tumors that can also affect this region and represent a major technical challenge to the surgeon. With the advances in the endoscopic technique, the vast majority of diseases that affect the FS can be treated according to Wolfgang Draf, who systemized the approaches into four types (I, IIa, IIb, III). Conclusion  Both benign and malignant diseases that affect the FS and FR can be successfully managed if one has a thorough understanding of the FS and FR anatomy, an individualized approach of the best surgical technique in each case, and the appropriate tools to operate in this region.

A 16-Year Study on Incidence and Progression of Diseased Sphenoethmoidal (Onodi) Cell

Traumatic operative injury of the optic nerve in an endoscopic sinus surgery may cause immediate or delayed blindness. It should be cautioned when operating in a sphenoethmoidal cell, or known as Onodi cell, with contact or bulge of the optic canal. It remains unclear how frequent progression to visual loss occurs and how long it progresses to visual loss because of a diseased sphenoethmoidal cell. Research to discuss these questions is expected to help decision making to treat diseased sphenoethmoidal cells. From July 2001 to June 2017, 216 patients received conservative endoscopic sinus surgery without opening a diseased sphenoethmoidal cell. We used their computed tomography images of paranasal sinuses to identify diseased sphenoethmoidal cells that could be associated with progression to visual loss. Among the 216 patients, 52.3% had at least one sphenoethmoidal cell, and 14.8% developed at least one diseased sphenoethmoidal cell. One patient developed acute visual loss 4412 days after the first computed tomography. Our results show that over half of the patients have a sphenoethmoidal cell but suggest a rare incidence of a diseased sphenoethmoidal cell progressing to visual loss during the follow-up period.

Endoscopy-assisted transoral resection of a parapharyngeal space schwannoma without mandibular dissection

Of the schwannomas that arise from the parapharyngeal space, those in the high cervical region are particularly invasive, requiring mandibular dissection. Because these tumors are benign, however, excessive surgical invasion and postoperative neurological complications should be avoided. Postoperative dropout symptoms may be avoided by intracapsular extraction, including nerve integrity monitoring (NIM) and narrow-band imaging (NBI). Video laryngoscopy surgery is reported to be useful for transoral resection of pharyngeal and laryngeal tumors. This report describes the transoral removal of a giant schwannoma located in the high cervical region from a 74-years-old man using a surgical support device without mandibular dissection. The tumor was located on the right lateral pharyngeal wall and extended from the upper oropharynx to the hypopharynx while compressing the epiglottis to the skull base. No separation was observed between the internal jugular vein and the internal carotid artery. The tumor was diagnosed as a schwannoma with no malignancy on the basis of the histology of a core needle biopsy (CNB), and was completely and safely removed endoscopically using NIM and NBI, with no need for an external incision or mandibular dissection. This case illustrates that even a huge sympathetic schwannoma located in the parapharyngeal space at a high cervical position can be excised transorally using video-laryngoscopic surgery (TOVS) without mandibular dissection.

Methodological Quality of Systematic Reviews and Meta-analyses Published in High-Impact Otolaryngology Journals

OBJECTIVE

To assess the methodological quality of intervention-focused systematic reviews (SRs) and meta-analyses (MAs) published in high-impact otolaryngology journals.

DATA SOURCES

Ovid Medline, Embase, and Cochrane Library.

REVIEW METHODS

A comprehensive search was performed for SR and MA citations from 2012 to 2017 in the 10 highest impact factor otolaryngology journals. Abstracts were screened to identify published manuscripts in which the authors indicated clearly that they were performing an SR or MA. Applying a modified typology of reviews, 4 reviewers characterized the review type as SR, MA, or another review type. A simplified version of the AMSTAR 2 (A MeaSurement Tool to Assess systematic Reviews 2) tool was used to assess the reporting and methodological quality of the SRs and MAs that were focused on interventions.

RESULTS

Search and abstract screening generated 499 manuscripts that identified themselves as performing an SR or MA. A substantial number (85/499, 17%) were review types other than SRs or MAs, including 34 (7%) that were literature reviews. In total, 236 SRs and MAs focused on interventions. Over 50% of these SRs and MAs had weaknesses in at least 3 of the 16 items in the AMSTAR 2, and over 40% had weaknesses in at least 2 of the 7 critical domains. Ninety-nine percent of SRs and MAs provided critically low confidence in the results of the reviews.

CONCLUSION

Intervention-focused SRs and MAs published in high-impact otolaryngology journals have important methodological limitations that diminish confidence in the results of these reviews.

Image-Guided Surgery and Intraoperative Imaging in Rhinology: Clinical Update and Current State of the Art

INTRODUCTION

Image-guided surgery (IGS) has gained widespread acceptance in otorhinolaryngology for its applications in sinus and skull base surgery. Although the core concepts of IGS have not changed, advances in image guidance technology, including the incorporation of intraoperative imaging, have the potential to enhance surgical education, allow for more rigorous preoperative planning, and aid in more complete surgery with improved outcomes.

OBJECTIVES

Provide a clinical update regarding the use of image guidance and intraoperative imaging in the field of rhinology and endoscopic skull base surgery with a focus on current state of the art technologies.

METHODS

English-language studies published in PubMed, Cochrane, and Embase were searched for articles relating to image-guided sinus surgery, skull base surgery, and intraoperative imaging. Relevant studies were reviewed and critical appraisals were included in this clinical update, highlighting current state of the art advances.

CONCLUSIONS

As image guidance and intraoperative imaging systems have advanced, their applications in sinus and skull base surgery have expanded. Both technologies offer invaluable real-time feedback on the status and progress of surgery, and thus may help to improve the completeness of surgery and overall outcomes. Recent advances such as augmented and virtual reality offer a window into the future of IGS. Future advancements should aim to enhance the surgeon's operative experience by improving user satisfaction and ultimately lead to better surgical results.

Medical Liability in Sinus Surgery: A Westlaw Database Analysis From 2000 to 2017

BACKGROUND

Medical malpractice occurs when a hospital or health-care provider through negligent act or omission results in an injury to a patient. More than 50% of otolaryngologists have faced at least 1 claim, with rhinology being the most litigated subspecialty. This study aims to analyze medical litigation trends in Rhinology from 2000 to 2017 in the United States.

METHODS

The Westlaw database was reviewed from 2000 to 2017. Data were compiled on the demographics of the plaintiffs, procedures, nature of damages, legal allegations, and the use of expert witnesses, physician demographics/practice characteristics, verdicts, indemnities, and county/state of case.

RESULTS

There were 75 cases that met inclusion criteria after review of 125 cases. Majority of cases went to trial over settlement (80%) and were found in the Northeast region of the United States (36%). Most common cited legal allegations were improper performance and failure to follow standard of care. The most common nature of injuries were eye injury (29%) and intracranial complications (27%). The highest payouts were for progression of disease followed by intracranial injury. Of the 75 total cases analyzed, 37 (49.3%) used expert witnesses. When an expert witness was used at trial, the verdict statistically favored the defendant (62.5%).

CONCLUSIONS

Our analysis reveals the importance of meticulous surgical techniques and thorough preoperative evaluations.

Outcomes in Pediatric Transsphenoidal Pituitary Surgery Stratified by the Use of Image Guidance: An Analysis of the Kids' Inpatient Database from 1997 to 2016

Background  To evaluate the utilization of image guidance technology for pediatric transsphenoidal pituitary resection (TSPR) and analyze the complication rates, length of stay (LOS), and total cost for such surgeries as function of time and utilization of image guidance. Methods  The Healthcare Cost and Utilization Project Kids' Inpatient Database (KID) was queried for all cases of TSPR between 1997 and 2016. Factors extracted included patient demographics, use of image guidance, LOS, total cost, and complications, including panhypopituitarism, diabetes insipidus (DI), cerebrospinal fluid (CSF) rhinorrhea, and cranial nerve (CN) III, IV, and VI palsies. Multivariate logistic regression was utilized to determine the odds ratio of developing panhypopituitarism, DI, CSF rhinorrhea, and CN palsies for image-guided versus nonimage-guided cases. A generalized linear model was used to determine the effect of image guidance on inflation-adjusted total cost and LOS. Results  A total of 1,297 cases of TSPR were included in the KID over this time period. The majority were female, Caucasian, and older than 15 years. Utilization of image guidance has rapidly increased since 2006. Complication rates were comparable, but when controlling for other factors, the use of image guidance showed a lower risk of postoperative DI ( p  = 0.05). The use of image guidance also resulted in a shorter LOS by 2.84 days ( p  < 0.001) with no associated increase in total cost ( p  = 0.663). Conclusion  The use of imaging guidance for pediatric TSPR has precipitously increased in recent years, as it is cost-effective, decreases LOS, and may lead to lower complication rates, such as DI.

Asymmetrical surface scanning registration for image-guided otologic surgery: A phantom study

OBJECTIVE

To develop a registration procedure to achieve a higher degree of registration accuracy in image-guided otological surgery, paying particular attention to the registration centroid.

METHODS

A head phantom was used to measure the target registration error (TRE) at measurement points at various depth from the surface of the head. The surface-matching registration was performed using a commercially available surgical navigation system. We registered the phantom using only one ear of either side (right 100% - left 0%, or right 0% - left 100%) or using both ears with variable ratios (right 75% - left 25%, right 50% - left 50%, or right 25% - left 75%).

RESULTS

The overall TRE was the smallest when registration was performed equally on both sides. However, the TRE at 20-50 mm from the surface was the smallest when the fiducial points for the registration were collected asymmetrically at a ratio of 75:25 and weighed heavier on the operating side, and this difference was statistically significant.

CONCLUSION

The accuracy of image-guided surgery can be improved by carefully planning the registration procedure without changing the procedure itself. Accurate image-guided surgery at the middle and inner ear was achieved using 75% of the point cloud for the operating side and 25% of that for the opposite side for the registration.

Fusion of augmented reality imaging with the endoscopic view for endonasal skull base surgery; a novel application for surgical navigation based on intraoperative cone beam computed tomography and optical tracking

Objective

Surgical navigation is a well-established tool in endoscopic skull base surgery. However, navigational and endoscopic views are usually displayed on separate monitors, forcing the surgeon to focus on one or the other. Aiming to provide real-time integration of endoscopic and diagnostic imaging information, we present a new navigation technique based on augmented reality with fusion of intraoperative cone beam computed tomography (CBCT) on the endoscopic view. The aim of this study was to evaluate the accuracy of the method.

Material and methods

An augmented reality surgical navigation system (ARSN) with 3D CBCT capability was used. The navigation system incorporates an optical tracking system (OTS) with four video cameras embedded in the flat detector of the motorized C-arm. Intra-operative CBCT images were fused with the view of the surgical field obtained by the endoscope’s camera. Accuracy of CBCT image co-registration was tested using a custom-made grid with incorporated 3D spheres.

Results

Co-registration of the CBCT image on the endoscopic view was performed. Accuracy of the overlay, measured as mean target registration error (TRE), was 0.55 mm with a standard deviation of 0.24 mm and with a median value of 0.51mm and interquartile range of 0.39˗˗0.68 mm.

Conclusion

We present a novel augmented reality surgical navigation system, with fusion of intraoperative CBCT on the endoscopic view. The system shows sub-millimeter accuracy.

Use of Mixed Reality Visualization in Endoscopic Endonasal Skull Base Surgery

BACKGROUND

Neuronavigation systems assist with spatial orientation during endoscopic transnasal skull base surgery, but they require a correlation of 3-dimensional (3D) views with 2-dimensional (2D) radiology studies.

OBJECTIVE

To outline an initial experience with a novel technology platform that provides intraoperative navigation using 3D reconstructions of patient anatomy for endoscopic surgery.

METHODS

A retrospective study of endoscopic anterior skull base and complex paranasal procedures was performed. Data from preoperative computed tomography and magnetic resonance imaging scans were fused to create 3D digital models of patient anatomy. Using the technology developed by Surgical Theater (Mayfield Village, Ohio), these reconstructions were designed to highlight particular anatomic regions of interest. The models were studied to guide the surgical approach and anticipate critical structures.

The reconstructions were linked with the navigational technology created by Brainlab (Munich, Germany) during endoscopic surgery. A dynamic image of the reconstruction was displayed alongside a matching endoscopic camera view. These 2 views could be overlaid to provide an immersive, mixed reality image of the patient's anatomy.

RESULTS

A total of 134 cases were performed. The pathologies included tumors of the anterior skull base or sinonasal cavity, inflammatory sinus disease, and cerebrospinal fluid leaks. Specific anatomic structures, such as the internal carotid arteries and optic nerves, were chosen for enhancement. Surgeons felt that the technology helped to guide the extent of bony dissection and to identify critical structures.

CONCLUSION

We describe the first clinical series of complex skull base pathologies treated using a novel mixed reality platform.

Use of a navigation system in endonasal surgery: Impact on surgical strategy and surgeon satisfaction. A prospective multicenter study

OBJECTIVES

Surgical navigation systems (SNS) are now widely used in endoscopic endonasal surgery. Benefit, however, has not been fully studied. The objective of this study was to evaluate the impact of an SNS in terms of performance of the surgical procedure and of surgeon satisfaction, in a prospective multicenter study.

MATERIALS AND METHODS

A multicenter prospective study included patients undergoing endoscopic endonasal surgery using the electromagnetic DigiPointeur® (DGP) SNS in 16 French hospitals. An observation form, completed by the surgeon immediately at end of procedure, included type of procedure, and any changes in strategy or extent of surgery related to use of the SNS. Surgeon satisfaction was rated on an analog scale, with self-assessment of stress experienced during the procedure.

RESULTS

The study included 311 patients operated on by 36 surgeons in 16 French hospitals. Ethmoidectomy was the most frequent procedure (90%); tumor resection was performed in 5.1% of cases. The SNS enabled more extensive surgery in 81% of cases, in particular by identifying and opening additional cells (57% of cases). Mean satisfaction was 8.6/10; surgeons reported decreased surgical stress thanks to the SNS in 95% of cases.

CONCLUSION

In this observational study, the use of an SNS increased the extent of surgery in 81% of cases, and had a positive impact on the stress perceived by the surgeon in 95% of cases.

Intraoperative Image-Guided Navigation in Craniofacial Surgery: Review and Grading of the Current Literature

INTRODUCTION

Image-guided navigation has existed for nearly 3 decades, but its adoption to craniofacial surgery has been slow. A systematic review of the literature was performed to assess the current status of navigation in craniofacial surgery.

METHODS

A Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) systematic review of the Medline and Web of Science databases was performed using a series of search terms related to Image-Guided Navigation and Craniofacial Surgery. Titles were then filtered for relevance and abstracts were reviewed for content. Single case reports were excluded as were animal, cadaver, and virtual data. Studies were categorized based on the type of study performed and graded using the Jadad scale and the Newcastle-Ottawa scales, when appropriate.

RESULTS

A total of 2030 titles were returned by our search criteria. Of these, 518 abstracts were reviewed, 208 full papers were evaluated, and 104 manuscripts were ultimately included in the study. A single randomized controlled trial was identified (Jadad score 3), and 12 studies were identified as being case control or case cohort studies (Average Newcastle-Ottawa score 6.8) The most common application of intraoperative surgical navigation cited was orbital surgery (n = 36), followed by maxillary surgery (n = 19). Higher quality studies more commonly pertained to the orbit (6/13), and consistently show improved results.

CONCLUSION

Image guided surgical navigation improves outcomes in orbital reconstruction. Although image guided navigation has promise in many aspects of craniofacial surgery, current literature is lacking and future studies addressing this paucity of data are needed before universal adoption can be recommended.

Cone-Beam Computed Tomography Allows Accurate Registration to Surgical Navigation Systems: A Multidevice Phantom Study

Background

Cone-beam computed tomography (CBCT) is a fast imaging technique with a substantially lower radiation dosage than conventional multidetector computed tomography (MDCT) for sinus imaging. Surgical navigation systems are increasingly being used in endoscopic sinus and skull base surgery, reducing perioperative morbidity.

Objective

To investigate CBCT as a low-radiation imaging modality for use in surgical navigation.

Methods

The required field of view was measured from the tip of the nose to the posterior clinoid process anteroposteriorly and the nasolabial angle to the roof of the frontal sinus superoinferiorly on 50 consecutive MDCT scans (male = 25; age = 17–85 years). A phantom head was manufactured by 3-dimensional printing and imaged using 3 CBCT scanners (Carestream, J Morita, and NewTom), a conventional MDCT scanner (Siemens), and highly accurate laser scanner (FARO). The phantom head was registered to 3 surgical navigation systems (Brainlab, Stryker, and Medtronic) using scans from each system.

Results

The required field of view (mean ± standard deviation) was measured as 107 ± 7.6 mm anteroposteriorly and 90.3 ± 9.6 mm superoinferiorly. Image error deviations from the laser scan (median ± interquartile range) were comparable for MDCT (0.19 ± 0.09 mm) and CBCT (CBCT 1: 0.15 ± 0.11 mm; CBCT 2: 0.33 ± 0.18 mm; and CBCT 3: 0.13 ± 0.13 mm) scanners. Fiducial registration error and target registration error were also comparable for MDCT- and CBCT-based navigation.

Conclusion

CBCT is a low-radiation preoperative imaging modality suitable for use in surgical navigation.

Automatic Registration for Navigation at the Anterior and Lateral Skull Base

OBJECTIVE

Navigation systems create a connection between imaging data and intraoperative situs, allowing the surgeon to consistently determine the location of instruments and patient anatomy during the surgical procedure. The best results regarding the target registration error (measurement uncertainty) are normally demonstrated using fiducials. This study aimed at investigating a new registration strategy for an electromagnetic navigation device.

METHODS

For evaluation of an electromagnetic navigation system and comparison of registration with screw markers and automatic registration, we are calculating the target registration error in the region of the paranasal sinuses/anterior and lateral skull base with the use of an electromagnetic navigation system and intraoperative digital volume tomography (cone-beam computed tomography). We carried out 10 registrations on a head model (total n = 150 measurements) and 10 registrations on 4 temporal bone specimens (total n = 160 measurements).

RESULTS

All in all, the automatic registration was easy to perform. For the models that were used, a significant difference between an automatic registration and the registration on fiducials was evident for just a limited number of screws. Furthermore, the observed differences varied in terms of the preferential registration procedure.

CONCLUSION

The automatic registration strategy seems to be an alternative to the established methods in artificial and cadaver models of intraoperative scenarios. Using intraoperative imaging, there is an option to resort to this kind of registration as needed.

Initial experience with image-guided surgical navigation in transoral surgery

BACKGROUND

Surgical navigation using image guidance may improve the safety and efficacy of transoral surgery (TOS); however, preoperative imaging cannot be accurately registered to the intraoperative state due to deformations resulting from placement of the laryngoscope or retractor. This proof of concept study explores feasibility and registration accuracy of surgical navigation for TOS by utilizing intraoperative imaging.

METHODS

Four patients undergoing TOS were recruited. Suspension laryngoscopy was performed with a CT-compatible laryngoscope. An intraoperative contrast enhanced CT scan was obtained and registered to fiducials placed on the neck, face, and laryngoscope.

RESULTS

All patients were successfully scanned and registered. Registration accuracy within the pharynx and larynx was 1 mm or less. Target registration was confirmed by localizing endoscopic and surface structures to the CT images. Successful tracking was performed in all 4 patients.

CONCLUSION

For surgical navigation during TOS, although a high level of registration accuracy can be achieved by utilizing intraoperative imaging, significant limitations of the existing technology have been identified. These limitations, as well as areas for future investigation, are discussed.

Applications of Augmented Reality in Otolaryngology: A Systematic Review

OBJECTIVE

Augmented reality (AR) is a rapidly developing technology. The aim of this systematic review was to (1) identify and evaluate applications of AR in otolaryngology and (2) examine trends in publication over time.

DATA SOURCES

PubMed and EMBASE.

REVIEW METHODS

A systematic review was performed according to PRISMA guidelines without temporal limits. Studies were included if they reported otolaryngology-related applications of AR. Exclusion criteria included non-English articles, abstracts, letters/commentaries, and reviews. A linear regression model was used to compare publication trends over time.

RESULTS

Twenty-three articles representing 18 AR platforms were included. Publications increased between 1997 and 2018 ( P < .05). Twelve studies were level 5 evidence; 9 studies, level 4; 1 study, level 2; and 1 study, level 1. There was no trend toward increased level of evidence over time. The most common subspecialties represented were rhinology (52.2%), head and neck (30.4%), and neurotology (26%). The most common purpose of AR was intraoperative guidance (54.5%), followed by surgical planning (24.2%) and procedural simulations (9.1%). The most common source of visual inputs was endoscopes (50%), followed by eyewear (22.2%) and microscopes (4.5%). Computed tomography was the most common virtual input (83.3%). Optical trackers and fiducial markers were the most common forms of tracking and registration, respectively (38.9% and 44.4%). Mean registration error was 2.48 mm.

CONCLUSION

AR holds promise in simulation, surgical planning, and perioperative navigation. Although level of evidence remains modest, the role of AR in otolaryngology has grown rapidly and continues to expand.

Better surgical outcome by image-guided navigation system in endoscopic removal of sinonasal inverted papilloma

PURPOSE

The purpose of this study was to validate and compare treatment outcomes for endoscopic resection of sinonasal inverted papilloma (IP) with or without the use of a navigation system.

MATERIALS AND METHODS

A total of 58 patients who underwent endoscopic resection of sinonasal inverted papilloma by a single surgeon from 2007 to 2016 at our institution were retrospectively reviewed. Depending on the use of the navigation system, subjects were divided into two groups: a conventional endoscopic resection group without navigation system (CER group) and a navigation-assisted endoscopic resection group (NER group).

RESULTS

There were 24 patients (41.4%) in the CER group and 34 patients (58.6%) in the NER group. Treatment outcomes showed that navigation-assisted endoscopic resection was a more beneficial surgical technique than conventional endoscopic resection for sinonasal IP. Post-surgical recurrence was noted in seven cases (29.2%) in the CER group and two cases (5.9%) in the NER group. Accordingly, the recurrence rate was significantly less in the NER group compared to the CER group (p = 0.026). There were two cases of complications (8.3%) in the CER group comprising cerebrospinal fluid leak and periorbital fat exposure, while no complications were noted for the NER group (p = 0.167).

CONCLUSION

This study demonstrated that navigation-assisted endoscopic removal of sinonasal IP is helpful for reducing recurrence and avoiding surgical complications. Therefore, navigation systems should be always considered when performing endoscopic removal of sinonasal IP.

Systematic Reviews and Meta-analysis in Rhinosinusitis: a Critical Review of the Reviews

PURPOSE OF REVIEW

There has been an explosion in the number of published systematic reviews on chronic rhinosinusitis in the last decade.

RECENT FINDINGS

While the aim of these reviews in facilitating evidence-based practice is laudable, poor quality reviews may contain significant bias that can mislead a non-discerning reader. Attention therefore must be given to review methodology before implanting findings. Organisations such as the Cochrane Collaboration promote high-quality reviews, but are limited in chronic sinus disease by heterogeneous outcomes and a paucity of randomised trials.