CSO (Canadian Society of Otolaryngology - Head & Neck Surgery) position paper on rhinologic and skull base surgery during the COVID-19 pandemic.

Healthcare services in many countries have been partially or completely disrupted by the Coronavirus (COVID-19) pandemic since its onset in the end of 2019. Amongst the most impacted are the elective medical and surgical services in order to conserve resources to care for COVID-19 patients. As the number of infected patients decrease across Canada, elective surgeries are being restarted in a staged manner. Since Otolaryngologists - Head & Neck Surgeons manage surgical diseases of the upper aerodigestive tract where the highest viral load reside, it is imperative that these surgeries resume in a safe manner. The aim of this document is to compile the current best evidence available and provide expert consensus on the safe restart of rhinologic and skull base surgeries while discussing the pre-operative, intra-operative, and post-operative care and tips. Risk assessment, patient selection, case triage, and pre-operative COVID-19 testing will be analyzed and discussed. These guidelines will also consider the optimal use of personal protective equipment for specific cases, general and specific operative room precautions, and practical tips of intra-operative maneuvers to optimize patient and provider safety. Given that the literature surrounding COVID-19 is rapidly evolving, these recommendations will serve to start our specialty back into elective rhinologic surgeries over the next months and they may change as we learn more about this disease.

Postoperative irrigation therapy after sinonasal tumor surgery.

BACKGROUND: Sinonasal care after endoscopic tumor resection aims to manage crusting, edema, mucus, and a healing cavity. High-volume irrigations have proved beneficial in this setting. The addition of corticosteroid to the irrigation is used for chronic rhinosinusitis (CRS) in modifying the postsurgical inflammatory response; however, its effect in endoscopic sinonasal tumor resection is unknown. Saline alone versus combination saline and corticosteroid irrigations in postoperative nasal care of sinonasal tumor patients was assessed. METHODS: A retrospective cohort of patients postendoscopic endonasal tumor resection was assessed. Patients used 240 mL of saline or 240 mL of saline with 1 mg of betamethasone daily. Nasal symptom scores (NSSs) and the 22-item Sino-Nasal Outcome test (SNOT-22) was recorded 3 months postoperatively. An endoscopic score was made of the area undergoing secondary healing at 3 months by two blinded assessors. RESULTS: Fifty-nine patients were assessed (aged 50.1 ± 18.26 years; 36% female subjects). The groups were similar in number (saline n = 31), treatment, and surgical characteristics. The endoscopic scores did not differ between the groups at 3 months. NSS was lower in the saline group (1.0 [interquartile range {IQR}, 3] versus 7.0 [IQR, 9]; p = 0.03) and, similarly, for SNOT-22 (0.24 [IQR, 1] versus 1.09 [IQR, 1]; p = 0.01) compared with the saline with steroid group. CONCLUSION: Although corticosteroid irrigations have become routine for managing inflammatory sinus disease at our center, their use after tumor surgery does not appear to be warranted. The inflammatory healing process after tumor surgery differs from CRS inflammation and may explain the observed findings.

Osteitis is a misnomer: a histopathology study in primary chronic rhinosinusitis.

BACKGROUND: The histological features of osteitis in chronic rhinosinusitis (CRS) in animal studies induced by bacterial inoculation into maxillary sinuses revealed inflammatory involvement of the underlying bone matrix and/or the Haversian system; however, human studies do not mention these findings. The objective of this study was to investigate the inflammatory characterization of osteitis in CRS. METHOD: A prospective study of primary CRS patients undergoing sinus surgery was conducted (August 2012 to April 2013). Bone-mucosa samples were taken from a predetermined site that correlated to a computed tomography location. Radiological bone thickness was measured. A blinded histopathological assessment included inflammatory infiltrate of bone, periosteal reaction, presence of osteoblasts or osteoclasts, fibrosis, and the percentage of new woven bone to total bone thickness, together with an overall opinion of whether neo-osteogenesis was present. RESULTS: Twenty-two primary CRS patients (age 45.8 ± 15.6 years; 59.1% female) were recruited. CRS with polyps accounted for 59.1% of patients. The bony thickness measured radiologically was a median 1.72 (interquartile range [IQR], 2.38; range, 0.3-12.14) mm. No samples (0%) had evidence of inflammatory infiltrate of bone; 90.9% had both osteoblasts present and new woven bone formation. Woven bone was greater with periosteal reaction (80.83% ± 9.25% vs. 47.50% ± 29.37%; p = 0.006), greater with osteoclasts present (80.00% ± 12.58% vs 59.00% ± 28.52%; p = 0.03), and greater when fibrosis was present (69.75% ± 24.14% vs 25.00% ± 7.07%; p = 0.003). CONCLUSION: Most primary CRS patients demonstrated evidence of new woven bone formation. True "osteitis" with inflammatory infiltrate of the bone was not observed. "Osteitis" is likely a process of neo-osteogenesis and bone remodeling, rather than bone inflammation in primary CRS.

Cadaveric study of the endoscopic endonasal transtubercular approach to the anterior communicating artery complex.

The endoscopic transnasal approach to the anterior communicating artery (ACoA) complex is not widely performed. This cadaveric study investigated the surgical relevance of the anterior endoscopic approach to the treatment of ACoA aneurysms. Bi-nasal endoscopic transtubercular surgery was carried out on fresh adult cadavers. Primary outcomes measures incorporated dimensions of the endonasal corridor (operative field depth, lateral limits, size of the transplanum craniotomy and dural opening); vascular exposure (proximal and distal anterior cerebral arteries [ACA], ACoA, clinoidal internal carotid artery [ICA] segment); and operative manoeuvrability defined by clip placements (ipsilateral and contralateral). Eight cadaver heads were used (mean age 84±7years, range 76-94 years, 75% female). Mean operative depth was 97±4mm. The lateral corridors were limited proximally by the alar rim openings (31±2mm), and distally by the optic nerves (22±6mm). The endonasal craniotomy dimensions were 21±5mm anteroposteriorly, and 22±4mm laterally. Vascular exposure was achieved in 100% of subjects for the ACoA segment and the ACA segments proximal to the ACoA (A1). The ACA segments distal to the ACoA (A2) were accessible only in 40% of subjects. Endonasal clip placement across the ACoA segment, clinoidal ICA, A1 and A2 were 100%, 90%, 90%, and 30%, respectively. The ventral endoscopic endonasal approach to the ACoA complex provides excellent vascular visualisation without brain retraction or gyrus rectus resection. However, the limitation in access to the A2 for temporary clip placement may prove to be a significant limitation of this approach.

The impact of culturable bacterial community on histopathology in chronic rhinosinusitis.

BACKGROUND: The influence of the microbial community on inflammatory subtype in chronic rhinosinusitis (CRS) has been proposed. Superantigen mechanisms potentially create a T helper 2 (Th-2)/eosinophilic dominated inflammation as a product of local flora rather than an intrinsic mucosal process. The associations between culturable bacteria and the histopathology and clinical features of CRS patients are described. METHODS: A cross-sectional study involving patients with CRS undergoing surgery was undertaken. Middle meatal swabs were performed at surgery for microbiological evaluation. Mucosal biopsies were taken and a blinded histopathological profile was performed. Disease specific quality of life and nasal symptom scores were recorded. The presence of culturable organisms and particular pathogens were compared with histopathology and clinical outcomes. RESULTS: A total of 95 patients were assessed (48.4% female, mean age 45.6 ± 14.0 years), of which 47.3% had a culturable organism. Tissue eosinophilia (>10/high-power field [HPF]) was found in 46.1% of these patients and 30.3% had neutrophilic infiltrate, with the presence of neither Gram-positive organisms, Gram-negative organisms, nor species correlating to pathology subtype. A culturable pathogen was a predictor of subepithelial fibrosis (χ(2) = 6.36, p = 0.04) and Gram-negative bacteria had the strongest association (χ(2) = 18.82, p < 0.01). There were no other significant associations with other clinical outcomes. CONCLUSION: The culturable bacterial community has little impact on histopathology in CRS. While more sensitive tests may detect bacteria in the sinuses, the impact of the simple "culturable" bacteria on the underlying pathologic process is limited. Changes, such as subepithelial fibrosis, suggest colonization may lead to undesirable local mucosal damage and remodeling.

Image-guided surgery influences perioperative morbidity from endoscopic sinus surgery: a systematic review and meta-analysis.

OBJECTIVE: Although image-guided surgery (IGS) is considered a valuable tool, its impact on perioperative morbidity for endoscopic sinus surgery (ESS) remains unclear. The evidence from reported literature is systematically reviewed with meta-analysis. DATA SOURCES: MEDLINE (1946 to September 14, 2012, week 2) and EMBASE (1974 to September 14, 2012, week 37). REVIEW METHODS: MEDLINE and EMBASE were searched using a search strategy for publications on IGS during ESS that reported original data on perioperative morbidity. PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines were followed. Both comparative cohort studies with non-IGS cases and case series were included. Primary outcome was major and total complications. Secondary outcomes were specific orbital and intracranial injury, major hemorrhage, ability to complete the operation, and revision surgery. The incidence of these events was defined as dichotomous variables and expressed as a risk ratio (RR) in a fixed-effects model. RESULTS: In total, 2586 articles fulfilled the search, producing 55 included studies. Fourteen were comparative cohorts of IGS and non-IGS sinus surgical patient populations used for meta-analysis. Among the cohorts, major complications were more common in the non-IGS group (RR = 0.48; 95% confidence interval [CI], 0.28-0.82; P = .007). Total complications were greater in the non-IGS group (RR = 0.66; 95% CI, 0.47-0.94; P = .02). All other outcomes did not reach significance on meta-analysis. CONCLUSION: Contrary to current review articles on the topic of IGS use during ESS, there is evidence from published studies that the use of IGS for sinus surgery, within selected populations, is associated with a lower risk of major and total complications compared with non-IGS sinus surgery.

Chapter 1: Sinonasal anatomy and function.

An understanding of paranasal sinus anatomy based on important fixed landmarks rather than variable anatomy is critical to ensure safe and complete surgery. The concept of the paranasal surgical box defines the anatomic limits of dissection. The boundaries of the surgical box include the middle turbinate medially, orbital wall laterally, and skull base superiorly. The "vertical component" of the surgical box defines the boundaries of the frontal recess and includes the middle turbinate and intersinus septum medially, medial orbital wall and orbital roof laterally, nasofrontal beak anteriorly, and skull base and posterior table of frontal sinus posteriorly. The paranasal sinuses are divided into anterior, posterior, and sphenoidal functional cavities based on their distinct drainage pathways into the nose. The ultimate goal of surgery is to create a functional sinus cavity. Application of the paranasal surgical box and its vertical component enables the surgeon to view the limits of dissection with a single position of the endoscope. This will ensure complete dissection of the functional sinonasal compartments and effectively avoid leaving behind disconnected cells from the surgical cavity, mucocele formation, mucous recirculation, overcome obstructive phenomenon and enable maximal delivery of topical therapy in the post-operative setting. This article reviews the structure and function of the nasal cartilages and turbinates. It also describes the concept of the paranasal surgical box, key anatomical landmarks and limits of dissection. Normal anatomy and common variants of normal anatomy are discussed.

Chapter 10: Sinonasal malignancies.

Malignant tumors of the sinonasal tract are uncommon tumors of the head and neck. Patients often present in the later years of life with unilateral symptoms and potential involvement of nearby structures such as the orbit, brain, or cranial nerves. Presenting symptoms are similar to patients suffering from inflammatory sinonasal disease and thus early diagnosis relies heavily on a high clinical suspicion. There are established risk factors based on exposure to the by-products of woodworking, metal, textile, and leather industries. Sinonasal malignancies are generally divided into those of epithelial origin (squamous cell carcinoma, adenocarcinoma, and adenoid cystic carcinoma) and nonepithelial origin (olfactory neuroblastoma, chondrosarcoma, and mucosal melanoma). Accurate histopathology confirmation and staging of the tumor is critical prior to making treatment decisions. Both computed tomography and magnetic resonance imaging are required to accurately determine the extent of local disease. Treatment is based on multimodality therapy, primarily surgical excision, and postoperative radiotherapy. This article reviews the classification of malignant tumors of the paranasal sinuses, their clinical presentation, relevant diagnostic investigations, and the principals of therapy and management.

Chapter 1: Sinonasal anatomy and function.

An understanding of paranasal sinus anatomy based on important fixed landmarks rather than variable anatomy is critical to ensure safe and complete surgery. The concept of the paranasal surgical box defines the anatomic limits of dissection. The boundaries of the surgical box include the middle turbinate medially, orbital wall laterally, and skull base superiorly. The "vertical component" of the surgical box defines the boundaries of the frontal recess and includes the middle turbinate and intersinus septum medially, medial orbital wall and orbital roof laterally, nasofrontal beak anteriorly, and skull base and posterior table of frontal sinus posteriorly. The paranasal sinuses are divided into anterior, posterior, and sphenoidal functional cavities based on their distinct drainage pathways into the nose. The ultimate goal of surgery is to create a functional sinus cavity. Application of the paranasal surgical box and its vertical component enables the surgeon to view the limits of dissection with a single position of the endoscope. This will ensure complete dissection of the functional sinonasal compartments and effectively avoid leaving behind disconnected cells from the surgical cavity, mucocele formation, mucous recirculation, overcome obstructive phenomenon and enable maximal delivery of topical therapy in the post-operative setting. This article reviews the structure and function of the nasal cartilages and turbinates. It also describes the concept of the paranasal surgical box, key anatomical landmarks and limits of dissection. Normal anatomy and common variants of normal anatomy are discussed.

Chapter 10: Sinonasal malignancies.

Malignant tumors of the sinonasal tract are uncommon tumors of the head and neck. Patients often present in the later years of life with unilateral symptoms and potential involvement of nearby structures such as the orbit, brain, or cranial nerves. Presenting symptoms are similar to patients suffering from inflammatory sinonasal disease and thus early diagnosis relies heavily on a high clinical suspicion. There are established risk factors based on exposure to the by-products of woodworking, metal, textile, and leather industries. Sinonasal malignancies are generally divided into those of epithelial origin (squamous cell carcinoma, adenocarcinoma, and adenoid cystic carcinoma) and nonepithelial origin (olfactory neuroblastoma, chondrosarcoma, and mucosal melanoma). Accurate histopathology confirmation and staging of the tumor is critical prior to making treatment decisions. Both computed tomography and magnetic resonance imaging are required to accurately determine the extent of local disease. Treatment is based on multimodality therapy, primarily surgical excision, and postoperative radiotherapy. This article reviews the classification of malignant tumors of the paranasal sinuses, their clinical presentation, relevant diagnostic investigations, and the principals of therapy and management.

Accuracy and reproducibility of automatic versus manual registration using a cone-beam CT image guidance system.

INTRODUCTION: Intraoperative imaging reveals morphologic changes and resolves anatomic uncertainties during surgery. The automatic registration (AR) approach provides registered intraoperative images for real-time tracking within seconds of acquisition. PURPOSE: (1) To design an AR device for clinical use integrated with cone-beam computed tomography, (2) to compare the accuracy and reproducibility of manual and automatic registration, and (3) to evaluate the robustness of the AR system. METHODS: An AR device consisting of an acrylic face shield with fiducials mounted on an adjustable arm was designed. Eight surface and five internal divot markers were placed with bony fixation to a cadaveric head. Internal markers were localized on the image representing the "true" location. This was compared to the positions localized using a navigational system when both manual registration and AR were applied. A series of surgical tasks and variation of the AR device height above the surgical field was performed, and target registration error (TRE) was measured. RESULTS: The mean fiducial registration error (FRE) for manual and automatic registration was 0.72 mm ± 0.03 and 0.41 mm ± 0.01, respectively. The mean TRE for manual and automatic registration was 0.89 mm ± 0.26 and 0.91 mm ± 0.25, respectively. CONCLUSIONS: AR offers a more accurate and reproducible FRE and a TRE equally comparable to that of manual registration. This system also demonstrates robustness with comparable accuracy and reproducibility throughout different surgical tasks and variation of AR device height up to 9 cm above the surgical field. This system is currently being translated into clinical trials.

Radiological features of ingested metallic mesh earphone pieces.

Foreign body ingestion remains a frequent cause of morbidity in infants and children. Symptoms vary with size, shape, location and composition of the foreign body. Flat objects tend to rotate to the greatest diameter of the esophageal lumen and become oriented in the coronal plane. We report two cases of ingested metallic mesh earphone pieces found in the upper esophagus. The foreign bodies were difficult to identify on posteroanterior images, but were more easily visualized on the lateral images. The presentation of this clinical entity and the recognition of its distinctive radiological findings may prevent a delayed diagnosis in the future and avoid potential complications.

Reconstruction of the midface and maxilla.

PURPOSE OF REVIEW: To review the current classification systems and reconstructive options available for restoration of maxillectomy defects. RECENT FINDINGS: Defects involving the midface can have a great functional and aesthetic impact on the patient. Adequate restoration of the complex three-dimensional maxillary structure is required to replace form and function of the native tissue. An in-depth discussion of appropriate recipient vessel selection and reconstructive options are included in this article. The superficial temporal vessel system is presented as a reliable anastomosis site for restoration of midfacial defects. In addition, the complications of vein grafting, arteriovenous fistula loops and alternative recipient vessels sites are addressed to manage the challenge of the vessel-depleted neck. The current indications, advantages and disadvantages of local, regional and free-flap reconstructive options available for maxillectomy defects are highlighted in order to aid the surgeon in appropriate flap selection. SUMMARY: A myriad of reconstructive options are available to restore maxillectomy defects. The surgeon must consider each defect and the needs of the individual patient when choosing the best suited reconstructive technique.

Predictors of unexpected hospital admissions after outpatient endoscopic sinus surgery: retrospective review.

BACKGROUND: Endoscopic sinus surgery (ESS) is typically performed on an outpatient basis in our centre. The purpose of this study is to determine the frequency of unexpected stays in patients who undergo ESS. This information would be useful to identify and to counsel these potential patients. METHODS: Retrospective chart review of 194 consecutive patients who had ESS during a 6-month span. Multivariate analysis was performed on 11 variables identified in the charts to determine whether any of the data predicted an unexpected admission. RESULTS: The unexpected rate of admission was 4.7%. Surgical complications causing admission occurred in 1% of the cases. Reasons for admissions included nausea and vomiting, hypotension, oxygen desaturation, headache, postoperative epistaxis, and observation for possible cerebrospinal fluid leak. None of the 11 variables that were examined showed statistical significance as independent predictors of unexpected admissions. However, two variables, the presence of comorbidities and the use of ondansetron, did approach statistical significance. CONCLUSIONS: Unexpected admissions following ESS are infrequent, and the reasons for admission are varied. In this study, although 9 of the 11 parameters evaluated showed no statistical significance as independent predictors of unexpected admissions, 2 did approach statistical significance. Intuitively, the presence of patient comorbidities would be expected to place the patient at greater risk of unexpected admission. Ondansetron is a potent antiemetic and is reserved for patients at risk or in those having severe symptoms. These patients would also be expected to have an increased risk of an unanticipated hospital stay.

Immunohistochemical investigation of hormone receptors and vascular endothelial growth factor concentration in vestibular schwannoma.

OBJECTIVES: To determine if a relationship exists between the presence of estrogen receptors (ER), progesterone receptors (PR), or vascular endothelial growth factor (VEGF) and the size, growth rate, and behavior of vestibular schwannoma tumors. DESIGN: Nine tumor samples from young female patients with large vestibular schwannoma tumors were preselected because they were presumed to be faster growing, more aggressive tumors. Immunohistochemical staining was performed using monoclonal mouse antibodies to ER, PR, and VEGF. RESULTS: The mean age of the study sample was 32.3 years, mean tumor size was 3.2 cm, and the average growth rate was 0.4 cm per 2 months. The results of immunohistochemical staining for ER and PR in all nine samples were unequivocally negative. Eight of nine tumor samples stained positive for VEGF, with five demonstrating low intensity and three demonstrating moderate intensity staining. CONCLUSIONS: There is histopathological evidence for the expression of VEGF in vestibular schwannomas but not for ER and PR. Further studies are necessary to determine the role of VEGF and other molecular pathways in the growth of vestibular schwannomas and the application of anti-VEGF therapy as a potential treatment option in the future.

Bilateral total knee arthroplasty--staged or simultaneous? Ontario's orthopedic surgeons reply.

BACKGROUND: Total knee replacement is now the most common joint replacement procedure performed in Ontario, and many patients require bilateral replacement. However, whether bilateral total knee arthroplasty (TKA) should be staged or simultaneous is hotly debated. To determine the current common operative practices of orthopedic surgeons in Ontario, we carried out a province-wide survey. METHODS: Orthopedic surgeons from Ontario listed in the 1999 Canadian Medical Directory or the membership list of the Canadian Orthopaedic Association were sent questionnaires, asking about their practice in the timing of bilateral TKA, tourniquet use, type of guide and use of techniques to minimize fat embolization. RESULTS: Of the 416 surveys mailed, 219 (53%) surgeons responded. The majority responded that they perform staged bilateral TKA (28% 3-mo interval and 37% 6-mo interval). Simultaneous TKA with 2 teams was the least performed procedure (2%). When performing bilateral TKA, 95% of surgeons use an intramedullary femoral alignment guide, 78% utilize an over-reamed entry hole and 53% suction the canal before inserting the guide rod. With respect to the tibia, 32% use an intramedullary guide, 60% over-ream the entry hole and 60% suction the entry hole; 22% of surgeons stated that they had never considered over-reaming or suctioning the canal to minimize fat embolization. CONCLUSIONS: There is no consensus regarding the timing of bilateral TKA in Ontario. Furthermore, many surgeons are not overdrilling or suctioning the femoral canal despite evidence in the literature that overdrilling may be beneficial in decreasing fat embolization. Further research is required to compare the risk of complications of bilateral TKA after staged versus simultaneous TKA.

Venting during prophylactic nailing for femoral metastases: current orthopedic practice.

INTRODUCTION: Reamed intramedullary nailing, recommended for impending fracture of a femur weakened by bone metastases, causes a rise in intramedullary pressure and increases the risk of a fat embolism syndrome. The pressure can be equalized by the technique of venting--drilling a hole into the distal cortex of the femur. Our objective was to study the current practice of orthopedic surgeons in Ontario with respect to venting during prophylactic intramedullary nailing for an impending femoral fracture due to bone metastases. METHODS: We mailed a questionnaire to all orthopedic surgeons from the Province of Ontario listed in the 1999 Canadian Medical Directory or on the Canadian Orthopaedic Association membership list, asking if they vent when prophylactically nailing an impending pathologic femoral fracture. The responses were modelled as a function of surgeon volume and year of graduation. RESULTS: Of the 415 surveys mailed, 223 (54%) surgeons responded. Of these, 81% reported having prophylactically treated a femoral metastatic lesion during the previous year; 67% treated 1 to 3 metastatic lesions and 14% treated more than 3; 19% did not treat a metastatic femoral lesion prophylactically. Over two-thirds of surgeons had never considered venting, whereas one-third always or sometimes vented the femoral canal. More recent graduates were 3 times more likely to vent than earlier (before 1980) graduates (odds ratio [OR] = 3.2, 95% confidence interval [CI] 1.6-6.5) as were those who treat a greater number of impending fractures (OR = 1.4, 95% CI 1.1-1.7). CONCLUSIONS: Although there is a theoretical rationale for routine venting, there is disagreement among Ontario orthopedic surgeons regarding the use of this technique during prophylactic nailing for femoral metastatic lesions. Prospective evidence will be required to warrant a change in the standard of care.