Endoscopic Transnasal Management of Meningoceles and Encephaloceles in Children: A Systematic Review

OBJECTIVE

To review surgical techniques used in the endoscopic transnasal repair of pediatric basal meningoencephaloceles and compare perioperative outcomes in children <2 and ≥2 years old.

DATA SOURCES

MEDLINE, EMBASE, and CENTRAL.

REVIEW METHODS

Data sources were searched from inception to August 22, 2022, using search terms relevant to endoscopic transnasal meningoencephalocele repair in children. Reviews and Meta-analyses were excluded. Primary outcomes were the incidence of intraoperative and postoperative complications, including cerebrospinal fluid leak, recurrence, and reintervention. Quality assessments were performed using Newcastle-Ottawa Scale, ROBIN-I, and NIH.

RESULTS

Overall, 217 patients across 61 studies were identified. The median age at surgery was 4 years (0-18 years). Fifty percent were female; 31% were <2 years. Most defects were meningoencephaloceles (56%), located transethmoidal (80%), and of congenital origin (83%). Seventy-five percent of repairs were multilayered. Children ≥2 years underwent multilayer repairs more frequently than those <2 years (P = 0.004). Children <2 years more frequently experienced postoperative cerebrospinal fluid leaks (P = 0.02), meningoencephalocele recurrence (P < 0.0001), and surgical reintervention (P = 0.005). Following multilayer repair, children <2 years were more likely to experience recurrence (P = 0.0001) and reintervention (P = 0.006).

CONCLUSION

Younger children with basal meningoencephaloceles appear to be at greater risk of postoperative complications following endoscopic endonasal repair, although the quality of available evidence is weakened by incomplete reporting. In the absence of preoperative cerebrospinal fluid leak or meningitis, it may be preferable to delay surgery as access is more conducive to successful repair in older children.

Facilitation of Definitive Cancer Diagnosis With Quantitative Molecular Assays of BRAF V600E and TERT Promoter Variants in Patients With Thyroid Nodules

Importance

Molecular testing of the presence of pathogenic genomic variants in a tumor without quantifying the variant allele fraction (VAF) does not differentiate the variation extent among tumors, often resulting in an inconclusive diagnosis because of interpatient variability.

Objective

To examine the association between the quantification of VAFs of BRAF V600E and TERT promoter variants and a definitive cancer diagnosis of thyroid tumors.

Design, Setting, and Participants

This diagnostic study analyzed a cohort of 378 surgically resected thyroid tumors with a maximum dimension of 1 cm or larger between March 15, 2016, and March 16, 2020, and a separate cohort of 217 residual thyroid fine-needle aspiration (FNA) biopsy specimens obtained from January 22, 2020, to March 2, 2021, at Mount Sinai Hospital, Toronto, Ontario, Canada. Data analysis was conducted between February 1, 2021, and February 1, 2023.

Exposures

Quantitative VAF assays of BRAF V600E and TERT promoter variants (C228T and C250T) were performed by digital polymerase chain reaction molecular assays.

Main Outcomes and Measures

The VAFs of BRAF V600E and TERT promoter variants were correlated with tumor histologic diagnoses and histopathologic features to delineate the association of VAF assays with tumor malignancy. The receiver operating characteristic curve analysis, sensitivity, specificity, positive predictive value, negative predictive value, and logistic regression analysis based on follow-up histopathologic types were used to determine the diagnostic utility of the quantitative molecular assays.

Results

A total of 595 specimens, including 378 surgically resected thyroid tumors and 217 thyroid nodule FNA biopsy specimens, were collected from 580 patients (436 [75.2%] female with a mean [SD] age of 50 [16] years and 144 [24.8%] male with a mean [SD] age of 55 [14] years). Sensitive VAF assays of 378 thyroid tumors revealed the presence of the BRAF V600E variant in 162 tumors (42.9%), with 26 (16.0%) at a low VAF of 1% or less and 136 (84.0%) at a high VAF of greater than 1%, and the presence of TERT promoter variants in 49 tumors (13.0%), including 45 C228T variants (91.8%), 15 (33.3%) of which were quantified as having a low VAF (≤1%) and 30 (66.7%) as having a high VAF (>1%), and 4 C250T variants (8.2%) with VAFs between 40.0% and 47.0%. All tumors detected with BRAF V600E and/or TERT promoter variants, whether at low or high VAFs, received a definitive cancer diagnosis. Further analysis delineated a significant association between high VAFs of either variant individually or different VAF levels for both variants in coexistence and aggressive histopathologic features of tumors. Excluding low VAFs assisted in identifying patients at an intermediate-to-high risk of recurrence (odds ratio, 5.3; 95% CI, 1.9-14.6; P = .001). The VAF assays on the residual FNA biopsy specimens showed a high agreement to those on surgical tissues (κ = 0.793, P < .001) and stratified malignancy in 40 of 183 indeterminate FNA cases (21.9%), with a sensitivity of 93.8% (95% CI, 67.7%-99.7%), specificity of 90.0% (95% CI, 75.4%-96.7%), positive predictive value of 78.9% (95% CI, 53.9%-93.0%), and negative predictive value of 97.3% (95% CI, 84.2%-99.9%).

Conclusions and Relevance

This diagnostic study suggests that sensitive quantitative VAF assays of BRAF V600E and TERT promoter variants can elucidate the interpatient variability in tumors and facilitate a definitive cancer diagnosis of thyroid nodules by differentiating the variation extent of genomic variants, even at low VAFs.

Postoperative opioid use following head and neck endocrine surgery: A multi-center prospective study

Background

Opioid abuse is widespread in North America and the over-prescription of opioids are a contributing factor. The goal of this prospective study was to quantify over-prescription rates, evaluate postoperative experiences of pain, and understand the impact of peri-operative factors such as adequate pain counseling and use of non-opioid analgesia.

Methods

Consecutive recruitment of patients undergoing head and neck endocrine surgery was undertaken from January 1st 2020 to December 31st 2021 at four Canadian hospitals in Ontario and Nova Scotia. Postoperative tracking of pain levels and analgesic requirements were employed. Chart review and preoperative and postoperative surveys provided information on counseling, use of local anesthesia, and disposal plans.

Results

A total of 125 adult patients were included in the final analysis. Total thyroidectomy was the most common procedure (40.8%). Median use of opioid tablets was 2 (IQR 0-4), with 79.5% of prescribed tablets unused. Patients who reported inadequate counseling (n = 35, 28.0%) were more likely to use opioids (57.2% vs. 37.8%, p < .05) and less likely to use non-opioid analgesia in the early postoperative course (42.9% vs. 63.3%, p < .05). Patients who received local anesthesia peri-operatively (46.4%, n = 58) reported less severe pain on average [2.86 (2.13) vs. 4.86 (2.19), p < .05] and used less analgesia on postoperative day one [0 MME (IQR 0-4) vs. 4 MME (IQR 0-8), p < .05].

Conclusion

Over-prescription of opioid analgesia following head and neck endocrine surgery is common. Patient counseling, use of non-opioid analgesia, and peri-operative local anesthesia were important factors in narcotic use reduction.

Level of evidence

Level 3.

Murine model for chronic rhinosinusitis: an interventional study

BACKGROUND

Chronic rhinosinusitis (CRS) is a complex inflammatory disease of the sinonasal tract. To understand this disease entity and develop targeted treatments, a reproducible animal model is paramount.

AIMS/OBJECTIVES

To optimize a murine model of eosinophilic CRS by establishing benchmark histological markers and validate its fidelity in evaluating intranasal treatments.

MATERIAL AND METHODS

Forty-five Balb/c mice were included in the 7-week protocol. Experimental animals (n = 20) were induced a CRS disease state upon receiving intraperitoneal sensitization with ovalbumin (OVA), followed by intranasal OVA with Aspergillus oryzae protease. Analysis of complete blood count with differential, peripheral blood smear, and histological markers from the nasal cavity mucosa were performed. CRS mice were additionally treated with intranasal saline (n = 5) or mometasone (n = 10) and compared with control groups of untreated CRS (n = 5) and healthy (n = 5) mice after week 7.

RESULTS

Histological analysis of experimental animal nasal mucosa revealed significantly higher levels of eosinophilic tissue infiltration/degranulation, hyaline droplets, Charcot-Leyden crystals, and respiratory epithelial thickness compared to healthy controls. Treatment with mometasone significantly reversed the histopathological changes observed in CRS mice.

CONCLUSION AND SIGNIFICANCE

This murine model induced substantial local eosinophilic inflammation within sinonasal mucosa, that was reversible with mometasone. This model may be used to evaluate the efficacy of therapeutics designed to target CRS.

Cribriform adenocarcinoma of the minor salivary glands: a case report

BACKGROUND

Polymorphous adenocarcinoma is the third most common malignant salivary gland tumor. Within polymorphous adenocarcinoma, cribriform adenocarcinoma of salivary glands is a rare subtype and resembles papillary thyroid carcinoma histopathologically. Diagnostically, cribriform adenocarcinoma of salivary glands is challenging for pathologists and surgeons alike as initial presentation and cytologic nuclear features can be easily confused with papillary thyroid carcinoma arising from a thyroglossal duct remnant or lingual thyroid.

CASE PRESENTATION

A healthy 64-year-old Caucasian woman presented to a community otolaryngologist with a 4-year history of progressive postnasal drip, globus sensation, and eventual dysphonia. Flexible fiberoptic laryngoscopy showed a large, smooth, vallecular lesion filling the oropharynx. Computed tomography imaging of the neck showed a rounded heterogeneous mass centered within the right aspect of the oropharynx measuring 4.2 × 4.4 × 4.5 cm. Fine needle aspiration biopsy was suspicious for papillary carcinoma due to microscopic findings of malignant cells, nuclear grooves, and a powdery chromatin pattern. In the operating room, the tumor was resected en bloc using a lateral pharyngotomy approach with partial resection of the right lateral hyoid. A limited cervical lymphadenectomy was performed to facilitate the lateral pharyngotomy approach and two out of three lymph nodes demonstrated regional metastatic disease. Nuclear grooves, nuclear membrane notching, and occasional intranuclear pseudoinclusions were identified, which are overlapping histopathological characteristics of papillary thyroid carcinoma and cribriform adenocarcinoma of salivary glands. It was negative for thyroglobulin and thyroid transcription factor-1, which was in keeping with cribriform adenocarcinoma of salivary glands rather than papillary thyroid carcinoma.

CONCLUSION

It is difficult to distinguish cribriform adenocarcinoma of salivary glands from papillary thyroid carcinoma solely by cytology, and the distinct characteristics of regional lymph node metastasis coupled with nuanced histologic differences should be emphasized in the evaluation of patients presenting with neck lymphadenopathy and an unknown primary or tongue mass. If sufficient fine needle aspiration biopsy material is available, thyroid transcription factor-1, thyroglobulin, or molecular testing may prove useful in differentiating cribriform adenocarcinoma of salivary glands from papillary thyroid carcinoma. A misdiagnosis of papillary thyroid carcinoma may lead to inappropriate treatment including unnecessary thyroidectomy. Therefore, it is critical for both pathologists and surgeons to be aware of this uncommon entity to avoid misdiagnosis and subsequent mismanagement.

Battle of the axes: simulation-based assessment of fine needle aspiration biopsies for thyroid nodules

Importance

Ultrasound-guided fine-needle aspiration biopsies (UGFNA) play a crucial role in the diagnosis of thyroid nodules. There are two techniques for performing an UGFNA: short-axis technique and long-axis technique. There is sparsity in the literature regarding the differences between these two techniques.

Objective

To compare the efficiency between long-axis and short-axis thyroid UGFNA techniques in trainees. Our secondary outcomes were to define the comfort level and learning curves of trainees.

Design

A longitudinal prospective cohort study, completed from December 2018 to November 2019, using the Blue Phantom Thyroid Model© for UGFNA. Face and construct validity of the model were verified. Residents completed UGFNA on an assigned nodule using both long-axis and short-axis techniques, the order of which was sequentially allocated. The rate and time to successful biopsy were obtained for both techniques. Biopsy attempts were repeated to establish learning curves.

Setting

Single-center study.

Participants

Fourteen Otolaryngology—Head & Neck Surgery residents at the University of Toronto.

Main outcome measure

Biopsy success and efficiency for novice learners completing UGFNA on a simulated thyroid model using long-axis and short-axis techniques.

Results

A trend towards higher odds of successful biopsy using the long-axis technique with no difference in procedure duration was observed (OR = 2.2, p = 0.095, CI = 0.87–5.39). Learning curve graphs appeared heterogenous according to trainee level. Trainees found the long-axis technique easier to perform (10/14, 71%), and the simulator valuable for learning (12/14, 86%).

Conclusion

Thyroid UGFNA using the long-axis technique may have an increased success rate and is generally favored by trainees for being easier to perform. Thyroid simulators have the potential to increase learner comfort and efficiency with UGFNA.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40463-022-00587-5.

Endoscopic treatment of sellar arachnoid cysts via a simple cyst-opening technique: Long-term outcomes from a single center

BACKGROUND

Sellar arachnoid cysts (SACs) are rare lesions that require treatment only if symptomatic. The endoscopic endonasal approach has been widely utilized. Despite their simple cystic appearance and the straight-forward surgical intervention there are important associated risks, with CSF leak being the prevalent one.

METHODS

A retrospective analysis of patients with pathologically confirmed SAC between January 2006 and December 2019 was conducted. A homogeneous simple cyst-opening technique and skull base reconstruction utilizing nasoseptal flaps was used.

RESULTS

Ten patients were identified (7 female and 3 male, median age was 54.5 years, range 20-77); 8 had newly diagnosed SACs whereas 2 recurrences from a previously microsurgically fenestrated SAC. Eight patients presented with visual symptoms (VS), 1 with VS and fatigue, and 1 with headaches. Neuro-ophthalmological and endocrinological assessments revealed visual field (VF) deficits in 6, visual acuity (VA) decline in 5 and hypopituitarism in 2 patients. Median calculated volume was 1.71 ml (range 0.27 - 2.54 ml). Postoperatively, no CSF leak and no further surgical complications were noted. VF improved in 4/6 while VA improved in 4/5 patients. Anterior pituitary function improved in 1, worsened in 1 and remained stable in 8 patients. One patient suffered diabetes insipidus. One recurrence was recorded 54 months postoperatively.

CONCLUSION

SACs can be effectively treated with a simple cyst-opening technique. The routine use of nasoseptal flaps significantly reduces the risk of CSF leak without compromising nasal quality of life in the long-term or mandating additional incisions. A long-term follow-up is important to monitor for late recurrences.

Association of the Implementation of a Standardized Thyroid Ultrasonography Reporting Program With Documentation of Nodule Characteristics

Importance

Although most thyroid nodules are benign, the potential for malignant neoplasms is associated with unnecessary workup in the form of imaging, fine-needle aspiration, and diagnostic surgery. The American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) is commonly used to assess the malignant neoplasm risk potential of thyroid nodules imaged by ultrasonography. However, standardized reporting of ACR TI-RADS descriptors is inconsistent.

Objective

To increase the documentation rate of ACR TI-RADS thyroid nodule characteristics to 80% in 18 months.

Design, Setting, and Participants

This prospective interrupted time series quality improvement study was conducted from December 1, 2018, to March 31, 2020, at a tertiary outpatient head and neck clinic among 229 patients who had at least 1 documented thyroid nodule identified on bedside clinic ultrasonography. Data analysis was performed throughout the entire study period because this was a quality improvement study with iterative small cycle changes; final analysis of the data was performed in April 2020.

Main Outcomes and Measures

The primary outcome was the documentation rates of 6 ACR TI-RADS ultrasonographic descriptors. Secondary outcomes included nodule fine-needle aspiration biopsy rate and physician-reported clinic flow efficiency.

Results

A total of 229 patients had at least 1 documented thyroid nodule and were included in the analysis. Size was the most frequently documented nodule characteristic (72 of 74 [97.3%]) at baseline, followed by echogenic foci (31 of 74 [41.9%]), composition (23 of 74 [31.1%]), echogenicity (17 of 74 [23.0%]), margin (6 of 74 [8.1%]), and shape (1 of 74 [1.4%]). After 3 Plan, Do, Study, Act (PDSA) cycles, the final intervention consisted of a standardized ultrasonography reporting form and educational initiatives for surgical trainees. After the third PDSA cycle (n = 36), reporting of nodule size, echogenic foci, and composition increased to 100%. Similarly, reporting of echogenicity (34 of 36 [94.4%]), shape (28 of 36 [77.8%]), and margin (25 of 36 [69.4%]) all increased. This represented a cumulative 90.3% documentation rate (195 of 216), a 56.5% increase from baseline (95% CI, 50.0%-61.9%). The standardized reporting form was used in 83.3% of eligible thyroid ultrasonography cases (30 of 36) after PDSA cycle 3, demonstrating good fidelity of implementation. There were no unintended consequences associated with clinic workflow, as a balancing measure, reported by staff surgeons.

Conclusions and Relevance

This study suggests that implementation of an ACR TI-RADS-based reporting form in conjunction with educational initiatives improved documentation of ultrasonographic thyroid nodule characteristics, potentially allowing for improved bedside risk stratification and communication among clinicians.

Surgical Nuances of Endoscopic Endonasal Resection of Craniopharyngiomas: 2-Dimensional Operative Video

Understanding of the microsurgical anatomy of the sella and suprasellar space is necessary for successful selection of surgical approaches and resection of craniopharyngiomas. Endoscopic endonasal surgery provides excellent exposure of the suprasellar space and has become the approach of choice for most of those tumors. In this video, we discuss the anatomical and surgical nuances for resection of craniopharyngiomas via an endoscopic transtuberculum transplanum approach. Anatomical dissections and a clinical case are used to illustrate the technique. This is the case of a 52-yr-old woman who presented to our clinic with a history of progressive visual decline and headaches, but no hormonal deficiencies. Magnetic resonance imaging demonstrated the presence of a sella suprasellar solid cystic lesion suggestive of a craniopharyngioma. The lesion was mainly located anterior to the chiasm, preinfundibular and medial to the posterior-communicating artery. Considering the patient presented with no hormonal deficits, it was decided to proceed with an endoscopic extended approach for maximum tumor resection while attempting to preserve the pituitary stalk and gland and its function. The patient provided consent to undergo the procedure and for the surgical video. After a binostril approach and harvesting of vascularized flap, a large sphenoidotomy was performed, followed by a transtuberculum transplanum approach. The tumor was resected with blunt and sharp dissection with careful preservation of the branches of the superior hypophyseal and posterior-communicating arteries. Closure was performed in a multilayer fashion, with dura substitute, fascia lata, and vascularized flap. The patient had visual improvement after surgery and was discharged at postoperative day 5 with no complications. Anatomical dissection pictures © 2019 Joao Paulo Almeida, MD. Used with permission.

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.

Surgical anatomy and technical nuances of the endoscopic endonasal approach to the anterior cranial fossa

Endoscopic endonasal approaches (EEA) to the skull base have significantly impacted the management of lesions located in the cranial base. Specifically, lesions arising from the anterior cranial fossa, such as pituitary macroadenomas, craniopharyngiomas meningiomas and craniofacial malignancies have benefited from the development of such approaches. Understanding of the anatomy of the anterior fossa is of utmost importance for the successful selection of the approach and application of surgical techniques in EEA. In the current manuscript, we review the most relevant points of surgical anatomy and nuances of the surgical technique of EEA to the anterior fossa. Anatomical landmarks for the transtuberculum transplanum and transcribriform approaches are discussed and a step-by-step description for those approaches is presented. We reinforce that safe and effective application of such techniques follow the same principles of other skull base surgery techniques: mastering of surgical anatomy, adequate case selection, correct instrumentation and surgical experience.

Endoscopic Endonasal Pituitary Surgery For Nonfunctioning Pituitary Adenomas: Long-Term Outcomes and Management of Recurrent Tumors

INTRODUCTION

Endoscopic endonasal approaches (EEAs) provide improved access and operative visualization for resection of pituitary adenomas. Although the technique has gained wide acceptance, there is a paucity of data regarding late recurrence.

OBJECTIVE

We aim to assess long-term outcomes of patients with nonfunctioning pituitary adenomas (NFPAs) who underwent EEA.

METHODS

We reviewed 269 patients operated on for an NFPA between 2005 and 2015. Clinical and radiologic factors including those potentially related to higher chances of recurrence were analyzed. Progression-free survival was analyzed using the Kaplan-Meier method, and univariate and multivariate survival were analyzed using a Cox regression model.

RESULTS

The study included 269 patients. The gross total resection rate was 46.0% (n = 124) but cavernous sinus involvement was present in almost half the patients (n = 115). The probability of recurrence at 5 years and 10 years was 22.0% and 47.2%, respectively. The median time to recurrence was 10 years for patients without cavernous sinus involvement and 6 years for those with cavernous sinus involvement. Univariate and multivariate analysis showed that tumor size, cavernous sinus invasion, anterior skull base extensions, and residual tumor were significantly associated with recurrence.

CONCLUSIONS

Recurrence rate of NFPA remains high despite the better visualization offered by EEA, especially in those tumors involving the cavernous sinus and/or previously operated on. Repeat surgery is adequate for tumor debulking and decompression of the optic apparatus but is unlikely to achieve gross total resection if a successful previous EEA has been performed. Radiation therapy is an effective option for management of recurrent tumors.

Evaluating YouTube as a Source of Patient Information for Functional Endoscopic Sinus Surgery

OBJECTIVE

To evaluate the quality of information presented on YouTube regarding functional endoscopic sinus surgery (FESS) for patients.

METHODS

YouTube was searched using FESS-specific keywords under the setting of "relevance." The first 50 videos from each keyword were reviewed and analyzed by 2 independent physician reviewers. Videos not related to FESS and duplicates were excluded. Outcome measures included the modified DISCERN score (range 0-5), the Journal of the American Medical Association (JAMA) benchmark criteria (range: 0-4), a novel scoring checklist for FESS assessing usefulness (range: 0-16), and the Video Power Index (VPI). Intraclass correlation coefficient (ICC) was calculated.

RESULTS

Of the 200 videos identified, 95 videos were analyzed after exclusions. Videos had an average VPI of 40.8 and SD 133.2. Average scores from the 3 objective checklists among all videos were low: modified DISCERN: 1.91, SD: 1.15; JAMA benchmark: 1.91, SD: 0.76; and FESS score: 3.54, SD: 1.77. The ICC between the 2 independent reviewers was excellent for all 3 checklists. We noted significant positive Pearson correlation between all 3 checklist scores (P < .001). In between-group comparisons of mean scores, there was significantly higher DISCERN and JAMA scores for videos from university/professional organizations, as compared to videos from medical advertising/for-profit companies and independent users. There were no significant differences in FESS scores noted between the 3 groups.

CONCLUSION

There were overall low scores across the modified DISCERN, JAMA benchmark criteria, and FESS scoring checklists, reflecting the poor quality of YouTube videos as a source of patient information for FESS.

Radiological Anatomy of the Olfactory Fossa: Is Skull Base Anatomy Really Ever “Safe”?

Objective Computed tomography (CT) is a powerful tool for delineating the anatomy of the anterior skull base. The goal of this study is to further characterize the relevant anatomical features of this area, along with other parameters important for endoscopic sinus surgery.

Design Retrospective case review.

Setting Tertiary care hospital.

Participants Thirty patients who had CT scans of the paranasal sinuses.

Main Outcome Measures The following features were assessed using image analysis software: olfactory fossa depth, the length and angle of the lateral lamella, fovea ethmoidalis length and shape, ethmoid roof height and slope, and the position and course of the anterior ethmoid artery. Statistical analysis was performed assessing for differences in the above parameters.

Results The mean olfactory fossa depth of the anterior and posterior skull base was 3.4  ± 1.1 and 2.4  ± 0.9 mm, respectively (p < 0.05). The mean lateral lamella length was 3.6  ± 0.9 mm, which did not demonstrate significant variability. The angle of the lateral lamella varied significantly by skull base position, measuring 63.1 ± 17.8 degrees anteriorly, and 39.1 ± 17.9 degrees posteriorly (p < 0.05). In scans classified as a Keros type I, 25.3% had lateral lamellae longer than 4 mm. Furthermore, 43.7% had lateral lamellae with angles less than 45 degrees. Moving anteriorly, the posterior skull base sloped downward in 46.7% of patients.

Conclusion Thorough preoperative assessment of CT scans is crucial to understanding the inherent variability of skull base anatomy. Even “safe” anatomy can still contain features such as long and acutely angled lateral lamella, which may predispose patients to iatrogenic injury.

Expanded Endoscopic Endonasal Approach for Removal of a Tuberculum Sella Meningioma

This 46-year-old female patient presented after a 6-month progressive right-sided visual loss, with a visual acuity of 20/60, a temporo/infranasal visual field deficit, and optic atrophy. The magnetic resonance imaging disclosed a tuberculum sella meningioma with minimal right medial canal invasion, however, no encasement of carotid arteries. Tuberculum sella meningiomas represent 5%-10% of intracranial meningiomas and are surgically challenging tumors that can severely hinder vision. The endoscopic approach allows for early coagulation of the tumor meningeal supply, and importantly, facilitates gross total removal without any manipulation of the optic nerve while preserving the superior hypophyseal arteries.^1-9.

Chemical Vapor Deposition of Organic-Inorganic Bismuth-Based Perovskite Films for Solar Cell Application

Perovskite solar cells have shown a rapid increase of performance and overcome the threshold of 20% power conversion efficiency (PCE). The main issues hampering commercialization are the lack of deposition methods for large areas, missing long-term device stability and the toxicity of the commonly used Pb-based compounds. In this work, we present a novel chemical vapor deposition (CVD) process for Pb-free air-stable methylammonium bismuth iodide (MBI) layers, which enables large-area production employing close-coupled showerhead technology. We demonstrate the influence of precursor rates on the layer morphology as well as on the optical and crystallographic properties. The impact of substrate temperature and layer thickness on the morphology of MBI crystallites is discussed. We obtain smooth layers with lateral crystallite sizes up to 500 nm. Moreover, the application of CVD-processed MBI layers in non-inverted perovskite solar cells is presented.

Effectiveness of discovery learning using a mobile otoscopy simulator on knowledge acquisition and retention in medical students: a randomized controlled trial

Background

Portable educational technologies, like simulators, afford students the opportunity to learn independently. A key question in education, is how to pair self-regulated learning (SRL) with direct instruction. A cloud-based portable otoscopy simulator was employed to compare two curricula involving SRL. Pre-clerkship medical students used a prototype smartphone application, a 3D ear attachment and an otoscope to complete either otoscopy curriculum.

Methods

Pre-clerkship medical students were recruited and randomized to two curriculum designs. The “Discovery then Instruction” group received the simulator one week before a traditional lecture, while the “Instruction then Discovery” group received it after the lecture. To assess participants’ ability to identify otoscopic pathology, we used a 100-item test at baseline, post-intervention and 2-week retention time points. Secondary outcomes included self-reported comfort, time spent using the device, and a survey on learning preferences.

Results

Thirty-four students completed the study. Analysis of knowledge acquisition and retention showed improvement in scores of both groups and no significant effects of group (F_1,31 = 0.53, p = 0.47). An analysis of participants’ self-reported comfort showed a significant group x test interaction (F_1,36 = 4.61, p = 0.04), where only the discovery then instruction group’s comfort improved significantly. Overall device usage was low, as the discovery then instruction group spent 21.47 ± 26.28 min, while the instruction then discovery group spent 13.84 ± 18.71 min. The discovery first group’s time spent with the simulator correlated moderately with their post-test score (r = 0.42, p = 0.07). After the intervention, most participants in both groups (63–68%) stated that they would prefer the instruction then discovery sequence.

Conclusions

Both curricular sequences led to improved knowledge scores with no statistically significant knowledge differences. When given minimal guidance, students engaged in discovery learning minimally. There is value in SRL in simulation education, and we plan to further improve our curricular design by considering learner behaviours identified in this study.

Postoperative Continuous Positive Airway Pressure Use and Nasal Saline Rinses After Endonasal Endoscopic Skull Base Surgery in Patients With Obstructive Sleep Apnea: A Practice Pattern Survey

BACKGROUND

Endoscopic skull base surgery continues to evolve in its indications, techniques, instrumentation, and postoperative care. As surgery of the skull base will often violate dura, intraoperative and postoperative cerebrospinal fluid (CSF) leak is not uncommon and represents a potential conduit for air and bacterial contamination. Patients with obstructive sleep apnea (OSA) requiring continuous positive airway pressure (CPAP) therapy undergoing skull base surgery represent a challenging group. However, there appears to be a paucity of consensus regarding the postoperative management of this patient population. The objective of this study is to examine practice patterns and expert opinion on the use of postoperative CPAP and nasal saline in patients with OSA.

METHODS

A 14-item survey was generated by consensus among expert authors and distributed online to members of the North American Skull Base society and other international skull base community members. Data were analyzed for median, mean, and standard deviation variables. Subgroup analysis was completed between surgeons from different geographical locations and operative experience. SPSS22 was utilized for all complex statistical analysis and figures.

RESULTS

Seventy-one responses were collected from skull base surgeons. In patients with OSA, respondents would resume patients' CPAP therapy after a mean of 10.1 days (median, 7; standard deviation [SD], 10.2), without a CSF leak. In the presence of a small CSF leak, the mean duration would increase to 14.3 days (median, 14; SD, 9.8) and to 20.7 days (median, 21; SD, 11.8) in the presence of a larger leak. A surgeon's choice to attribute the relationship between delaying the start of nasal saline and CPAP after the endoscopic skull base surgery with progressively more challenging skull base repair was found to be statistically significant ( P < .001).

CONCLUSION

Saline and CPAP therapies are initiated after the endoscopic skull base surgical repairs by surgeons at an increasing temporal delay in relation to the degree and complexity of the skull base defect repaired.

Impact of Dural Resection on Sinonasal Malignancies with Skull Base Encroachment or Erosion

Objectives  (1) To determine the occult rate of dural invasion in patients with tumors extending to and/or eroding the bony anterior skull base but without evidence of dural invasion on preoperative imaging. (2) To determine the impact of dural resection and of skull base erosion on survival outcomes in this group of patients (without evidence of dural invasion upon preoperative imaging). Study Design  Retrospective study. Setting  Tertiary care academic center. Participants  Patients with sinonasal malignancies with anterior skull base encroachment/erosion without dural invasion on preoperative imaging treated surgically. Main Outcome Measures  (1) Histopathologic disease in the dura in patients who had dural resection and (2) Oncologic outcomes (5-year local recurrence, dural recurrence, disease-specific survival, and overall survival) in patients with and without dural resection, and patients with and without skull base erosion. Results  Thirty-seven patients were included. The occult rate of dural invasion was 54%. Patients with dural resection had improved margin control versus those without dural resection (90% vs 56%, p  = 0.02). Dural resection improved 5-year overall survival only in patients with esthesioneuroblastoma compared with bony skull base resection alone (100% vs 75%, p  = 0.03). Patients with skull base erosion had reduced local control versus those without erosion (63% vs 93%, p  = 0.047). Conclusion  This study suggests a substantial rate of occult dural invasion despite no overt imaging findings. Dural resection may be associated with improved margin control, but no oncologic benefit except for esthesioneuroblastomas, although treatment heterogeneity and small sample size may limit conclusions.

Recurrence of Anterior Skull Base Meningiomas After Endoscopic Endonasal Resection: 10 Years' Experience in a Series of 52 Endoscopic and Transcranial Cases

INTRODUCTION

Although the indication of endoscopic approaches for anterior skull base meningiomas (ASBM) has been progressively refined, there remains a paucity of data on recurrence rates after resection. To analyze and compare recurrence rates of ASBM resected through endoscopic endonasal (EEE) versus transcranial (TCA) approaches.

MATERIAL AND METHODS

We performed a retrospective analysis of patients submitted to the EEE or TCA approach for ASBM resection from May 2006 to January 2016 in our center. Clinical, radiological, and pathology data were retrieved for analysis. Tumor size, location, surgical technique, extent of resection, and tumor grade were assessed. The 2 groups were compared to identify predictors and differences regarding tumor recurrence.

RESULTS

Fifty-two patients (17 olfactory groove meningioma [OGM] and 35 tuberculum sellae meningioma [TSM]) were included; 26 (6 OGM and 20 TSM) underwent EEE and 26 (13 OGM and 13 TSM) TCA, with a mean follow-up of 41 months. Gross total resection was achieved in 38 (73%) patients (18 [69%] in EEE and 20 [77%] in TCA). Eight (15%) patients presented with recurrence: 5 (19%) in the EEE group and 3 (11.5%) in the TCA group without a statistical difference (P = 0.69). Among the recurrences, gross total resection had been achieved in 1 case of each group. In the EEE group, 1 patient underwent TCA for a recurrent tumor and another patient was referred for radiosurgery.

CONCLUSIONS

This study has shown an overall similar recurrence rate of ASBM regardless of the technique used. However, the analysis of larger series with longer follow-up is necessary to clearly define the indications and to fully validate the efficacy of EEE.

Improved luminescence properties of MoS2 monolayers grown via MOCVD: role of pre-treatment and growth parameters

Fabrication of transition metal dichalcogenides (TMDCs) via metalorganic chemical vapor deposition (MOCVD) represents one of the most attractive routes to large-scale 2D material layers. Although good homogeneity and electrical conductance have been reported recently, the relation between growth parameters and photoluminescence (PL) intensity-one of the most important parameters for optoelectronic applications-has not yet been discussed for MOCVD TMDCs. In this work, MoS₂ is grown via MOCVD on sapphire (0001) substrates using molybdenum hexacarbonyl (Mo(CO)₆, MCO) and di-tert-butyl sulphide as precursor materials. A prebake step under H₂ atmosphere combined with a reduced MCO precursor flow increases the crystal grain size by one order of magnitude and strongly enhances PL intensity with a clear correlation to the grain size. A decrease of the linewidth of both Raman resonances and PL spectra down to full width at half maxima of 3.2 cm^-1 for the E _2g Raman mode and 60 meV for the overall PL spectrum indicate a reduced defect density at optimized growth conditions.

A challenge-response endoscopic sinus surgery specific checklist as an add-on to standard surgical checklist: an evaluation of potential safety and quality improvement issues

BACKGROUND

The goal of this study was to develop and evaluate the impact of an aviation-style challenge and response sinus surgery-specific checklist on potential safety and equipment issues during sinus surgery at a tertiary academic health center. The secondary goal was to assess the potential impact of use of the checklist on surgical times during, before, and after surgery. This initiative is designed to be utilized in conjunction with the "standard" World Health Organization (WHO) surgical checklist. Although endoscopic sinus surgery is generally considered a safe procedure, avoidable complications and potential safety concerns continue to occur. The WHO surgical checklist does not directly address certain surgery-specific issues, which may be of particular relevance for endoscopic sinus surgery.

METHODS

This prospective observational pilot study monitored compliance with and compared the occurrence of safety and equipment issues before and after implementation of the checklist. Forty-seven consecutive endoscopic surgeries were audited; the first 8 without the checklist and the following 39 with the checklist. The checklist was compiled by evaluating the patient journey, utilizing the available literature, expert consensus, and finally reevaluation with audit type cases. The final checklist was developed with all relevant stakeholders involved in a Delphi method.

RESULTS

Implementing this specific surgical checklist in 39 cases at our institution, allowed us to identify and rectify 35 separate instances of potentially unsafe, improper or inefficient preoperative setup. These incidents included issues with labeling of topical vasoconstrictor or injectable anesthetics (3, 7.7%) and availability, function and/or position of video monitors (2, 5.1%), endoscope (6, 15.4%), microdebrider (6, 15.4%), bipolar cautery (6, 15.4%), and suctions (12, 30.8%).

CONCLUSION

The design and integration of this checklist for endoscopic sinus surgery, has helped improve efficiency and patient safety in the operating room setting.

Extended Endoscopic Approach for Resection of Craniopharyngiomas

Objectives  Extended endoscopic approaches are useful for resection of selected craniopharyngiomas. Midline, extraventricular, and predominantly cystic lesions are good candidates for endoscopic resection. In this video, we demonstrate the endoscopic endonasal resection of a large suprasellar craniopharyngioma and discuss the nuances of the surgical technique.

Design/Setting  Surgical video of an extended endoscopic approach for resection of a suprasellar craniopharyngioma.

Results  We report the case of a 56-year-old woman who presented with bitemporal hemianopsia and visual acuity deterioration secondary to a large suprasellar solid–cystic lesion. The patient underwent an extended endoscopic transtuberculum approach for resection of the lesion, which was diagnosed as a papillary craniopharyngioma. This video discusses the anatomy and surgical technique applied for endoscopic resection of such lesions.

Conclusion  Endoscopic endonasal surgery is a useful technique for management of craniopharyngiomas. It is associated with good clinical outcomes in selected cases. Complications, such as postoperative CSF leak, may occur and should be carefully managed.

The link to the video can be found at: https://youtu.be/EneOCiQE7yo .

Social media in otolaryngology-head and neck surgery

The objective of this study was to assess the current use of social media tools within Canadian otolaryngology-head and neck surgery (OHNS) programs and to assess the interest within these programs to integrate social media for networking, social, and educational programs. A prospective study from September 2013 to February 2014 was performed involving residents and faculty in Canadian OHNS programs. A 26-item questionnaire was created and sent to staff and resident physicians who met the study inclusion criteria using an online survey tool (http://surveymonkey.com). There were 101 respondents for a 10% response rate. More than half (58.4%) of respondents reported use of social media for personal and/or professional matters. Residents and junior faculty physicians 39 years and younger were more likely to have social media accounts and used them more frequently than their older counterparts. Among staff physicians, pediatric otolaryngologists had the highest rate of use, and otologists exhibited the lowest rate. Cellular phones were the most commonly used devices to access social media sites. Fewer than 35% of social media users failed to separate their personal and professional accounts. Although OHNS trainees and practicing physicians identified the potential benefits of social media tools in their specialty, most were unsure how to apply these tools to their practice. Ours is the first study to assess social media use in OHNS. Otolaryngologists are currently using social media; however, their application as a communication and educational tool in otolaryngology remains to be defined.

Costs and Perioperative Outcomes Associated with Open versus Endoscopic Resection of Sinonasal Malignancies with Skull Base Involvement

Objective  To compare financial and perioperative outcomes between endoscopic and open surgical approaches in the surgical management of sinonasal malignancies. Design  Retrospective chart review. Setting  Tertiary care hospital. Participants  Patients undergoing surgical resection of a sinonasal malignancy from January 2000 to December 2014. Main Outcome Measures  In-hospital costs, complications, and length of stay (LOS). Results  Of 106 patients, 91 received open surgery (19 free flap and 72 non-free flap) and 15 were treated with purely endoscopic approaches. Free flaps had a significantly higher average cost, operative time, and LOS compared to both non-free flap ( p  < 0.001, < 0.001, and < 0.01) and endoscopic ( p  = 0.01, 0.04, and < 0.01) groups. There were no significant differences in average costs between endoscopic and non-free flap groups ($19,157 vs. $14,806, p  = 0.20) or LOS (5.7 vs. 6.4 days, p  = 0.72). Compared with the non-free flap group, the endoscopic group had a longer average operative time (8.3 vs. 5.5 hours, p  < 0.01) and higher rates of cerebrospinal fluid (CSF) leak (13 vs. 0%, p  = 0.01) and intensive care unit (ICU) admission (80 vs. 36%, p  < 0.01). Surgical approach (open vs. endoscopic) was not a significant predictor of any financial or perioperative outcome on multivariable analysis. Conclusion  Hospital costs are comparable between endoscopic and open approaches when no free tissue reconstruction is required. Longer operative times, higher CSF leak rates, and our institutional protocol necessitating ICU admission for endoscopic cases may account for the failure to demonstrate cost savings with endoscopic surgery.

Open versus endoscopic septoplasty techniques: A systematic review and meta-analysis

BACKGROUND

Septal deviation is a condition of high prevalence, which ranges from 22% in newborns to 90% in adults. Surgical intervention is frequently considered in the management of patients with symptoms. Although many surgeons prefer either the endoscopic or the open approach to septoplasty, there is an ongoing debate regarding comparative outcomes between the two approaches.

OBJECTIVE

The purpose of this study was to systematically review the literature and provide pooled summary estimates to evaluate the efficacy and safety of open versus endoscopic septoplasty techniques.

METHODS

This study was registered with PROSPERO (CRD42014010730). MEDLINE, EMBASE, Google Scholar, CINAHL, Web of Science, and The Cochrane Central Registry for Randomized Trials were searched for relevant studies by using the following keywords in varying combinations: "nasal septum," "nasal obstruction," "nasal cartilages," "nose," "nose diseases," "surgery," "nasal/septal deviation," and "septoplasty." All the studies that compared open versus endoscopic septoplasty techniques for the management of symptomatic septal deviation were considered. Two reviewers independently extracted data by using a preestablished extraction form and performed quality assessment by using the Jadad and Newcastle Ottawa Scales. Weighted pooled estimates were calculated and reported, along with relative risks and 95% confidence intervals.

RESULTS

Fourteen studies met our inclusion criteria. When comparing open versus endoscopic septoplasty techniques, there was significant improvement in postoperative symptoms (i.e., nasal obstruction, headaches) (p < 0.05) in the endoscopic septoplasty group. There also were significantly fewer complications associated with the endoscopic septoplasty technique (p < 0.05). Based on the quality assessment, included studies were deemed at a moderate-to-high risk of bias.

CONCLUSION

Our analysis indicated that endoscopic septoplasty may have some advantages over open septoplasty. However, our findings should be taken with caution given the poor quality of included studies.

Preliminary cross-sectional reliability and validity of the Skull Base Inventory (SBI) quality of life questionnaire

Background

The Skull Base Inventory (SBI) was developed to assess the quality of life of patients undergoing endoscopic or open approaches for anterior and central skull base pathologies. In this study, we sought to establish the discriminative and evaluative properties for this instrument.

Methods

The SBI was administered in a cross-sectional fashion to patients who previously had skull base surgery after treatment and then again 2 weeks after completing the instrument. Internal consistency, test-retest reliability, and construct validity were determined. Four constructs were evaluated with the following a priori hypotheses: lower scores will be seen in patients with 1.malignant versus benign histology, 2.a history of radiation versus none, and those with 3.recurrences versus no recurrence, and 4.items deemed relevant versus irrelevant by respondents.

Results

Fifty-two patients completed the questionnaire; 32 had endoscopic and 20 open surgeries. Internal consistency was good (>0.7 and <0.95) for all domains except one. Test-retest reliability was good (>0.70) for 38 of 41 items. Four constructs were evaluated and three were consistent with a priori hypotheses (p < 0.05). The instrument failed to confirm the hypothesis that malignant tumours are associated with poorer scores than benign.

Conclusions

The SBI demonstrated preliminary reliability and validity for discriminative use.

Three-dimensional virtual navigation versus conventional image guidance: A randomized controlled trial

OBJECTIVES/HYPOTHESIS

Providing image guidance in a 3-dimensional (3D) format, visually more in keeping with the operative field, could potentially reduce workload and lead to faster and more accurate navigation. We wished to assess a 3D virtual-view surgical navigation prototype in comparison to a traditional 2D system.

METHODS

Thirty-seven otolaryngology surgeons and trainees completed a randomized crossover navigation exercise on a cadaver model. Each subject identified three sinonasal landmarks with 3D virtual (3DV) image guidance and three landmarks with conventional cross-sectional computed tomography (CT) image guidance. Subjects were randomized with regard to which side and display type was tested initially. Accuracy, task completion time, and task workload were recorded.

RESULTS

Display type did not influence accuracy (P > 0.2) or efficiency (P > 0.3) for any of the six landmarks investigated. Pooled landmark data revealed a trend of improved accuracy in the 3DV group by 0.44 millimeters (95% confidence interval [0.00-0.88]). High-volume surgeons were significantly faster (P < 0.01) and had reduced workload scores in all domains (P < 0.01), but they were no more accurate (P > 0.28).

CONCLUSION

Real-time 3D image guidance did not influence accuracy, efficiency, or task workload when compared to conventional triplanar image guidance. The subtle pooled accuracy advantage for the 3DV view is unlikely to be of clinical significance. Experience level was strongly correlated to task completion time and workload but did not influence accuracy.

LEVEL OF EVIDENCE

N/A. Laryngoscope, 126:1510-1515, 2016.

Squeeze bottle versus saline spray after endoscopic sinus surgery for chronic rhinosinusitis: a pilot multicentre trial

BACKGROUND

There is a need for controlled trials to guide the perioperative management of patients undergoing endoscopic sinus surgery (ESS). The authors performed a pilot multicenter trial to compare two types of saline delivery devices in this population.

METHODS

Patients were randomized to high volume saline irrigation with a squeeze bottle and low volume saline spray after ESS in patients with chronic rhinosinusitis (CRS). Surgeons were blinded to treatment, and one-month postoperative scores for sinonasal outcomes [Sinonasal Outcome Test-22 (SNOT-22)] scale, nasal and sinus symptom score (NSS), and perioperative sinus endoscopy (POSE) scale were compared with preoperative scores.

RESULTS

Nine centers provided data for 86 patients. All three outcomes measures improved significantly for both groups. Saline spray: SNOT-22 48.8 versus. 23.7, treatment effect 25.1 (95% confidence interval [CI], 17.9-32.2), POSE 21.1 versus. 8.4, treatment effect 12.7 (95% CI, 9.2-16.1), and NSS 8.2 versus 5.0, treatment effect 3.1 (95% CI, 1.4-4.9) pre- and postoperatively, respectively (all p < 0.0001). Squeeze bottle: SNOT-22 49.5 versus 23.6, treatment effect 25.9 (95% CI, 20.3-31.6), POSE 18.6 versus 9.2, treatment effect 9.3, (95% CI 6.7-12.0), and NSS 9.0 versus 5.7, treatment effect 3.3 (95% CI, 2.3-4.3) pre- and postoperatively, respectively (all p < 0.0001). Analysis of variance did not identify a difference between the two treatment groups. Subgroup analysis based on preoperative disease severity did not change the nonassociation of saline bottle with outcome measures. Post hoc sample size calculation determined that 176 patients is required to detect an 8.9-point difference in SNOT-22 scores.

CONCLUSION

In this pilot multicenter trial examining patients with chronic rhinosinusitis undergoing ESS, both squeeze bottle and saline spray showed significant improvement in SNOT-22, POSE, and NSS scores at one-month postoperatively. Because the study was nonpowered, we cannot rule out a potential difference between the two treatment groups.

3D Rapid Prototyping for Otolaryngology-Head and Neck Surgery: Applications in Image-Guidance, Surgical Simulation and Patient-Specific Modeling

The aim of this study was to demonstrate the role of advanced fabrication technology across a broad spectrum of head and neck surgical procedures, including applications in endoscopic sinus surgery, skull base surgery, and maxillofacial reconstruction. The initial case studies demonstrated three applications of rapid prototyping technology are in head and neck surgery: i) a mono-material paranasal sinus phantom for endoscopy training ii) a multi-material skull base simulator and iii) 3D patient-specific mandible templates. Digital processing of these phantoms is based on real patient or cadaveric 3D images such as CT or MRI data. Three endoscopic sinus surgeons examined the realism of the endoscopist training phantom. One experienced endoscopic skull base surgeon conducted advanced sinus procedures on the high-fidelity multi-material skull base simulator. Ten patients participated in a prospective clinical study examining patient-specific modeling for mandibular reconstructive surgery. Qualitative feedback to assess the realism of the endoscopy training phantom and high-fidelity multi-material phantom was acquired. Conformance comparisons using assessments from the blinded reconstructive surgeons measured the geometric performance between intra-operative and pre-operative reconstruction mandible plates. Both the endoscopy training phantom and the high-fidelity multi-material phantom received positive feedback on the realistic structure of the phantom models. Results suggested further improvement on the soft tissue structure of the phantom models is necessary. In the patient-specific mandible template study, the pre-operative plates were judged by two blinded surgeons as providing optimal conformance in 7 out of 10 cases. No statistical differences were found in plate fabrication time and conformance, with pre-operative plating providing the advantage of reducing time spent in the operation room. The applicability of common model design and fabrication techniques across a variety of otolaryngological sub-specialties suggests an emerging role for rapid prototyping technology in surgical education, procedure simulation, and clinical practice.

Post-operative stimulated thyroglobulin and neck ultrasound as personalized criteria for risk stratification and radioactive iodine selection in low- and intermediate-risk papillary thyroid cancer

The purpose of this study was to demonstrate the utility of a personalized risk stratification and radioactive iodine (RAI) selection protocol (PRSP) using post-operative stimulated thyroglobulin (Stim-Tg) and neck ultrasound in low- and intermediate-risk papillary thyroid carcinoma (PTC) patients. Patients with PTC tumors ≥1 cm were prospectively followed after total thyroidectomy and selective therapeutic central compartment neck dissection. Low/intermediate risk was defined as PTC confined to the thyroid or central (level VI) lymph nodes. Stim-Tg and neck ultrasound were performed approximately 3 months after surgery and used to guide RAI selection. Patients with Stim-Tg < 1 µg/L did not receive RAI, while those with Stim-Tg >5 µg/L routinely did. Those with Stim-Tg 1-5 µg/L received RAI on the basis of several clinical risk factors. Patients were followed for >6 years with serial neck ultrasound and basal/stimulated thyroglobulin. Among the 129 patients, 84 (65 %) had undetectable Stim-Tg after initial surgery, 40 (31 %) had Stim-Tg of 1-5 µg/L, and 5 (4 %) had Stim-Tg >5 µg/L. RAI was administered to 8 (20 %) patients with Stim-Tg 1-5 µg/L and 5 (100 %) with Stim-Tg >5 µg/L. Using this approach, RAI therapy was avoided in 17/20 (85 %) patients with tumors >4 cm, in 72/81 (89 %) patients older than 45 years, and in 6/9 (67 %) patients with central lymph node involvement. To date, 116 (90 %) patients in this cohort have not received RAI therapy with no evidence of residual/recurrent disease, whereas among the 13 patients who received RAI, 1 (8 %) had pathologic residual/recurrence disease. Using the proposed PRSP, RAI can be avoided in the majority of low/intermediate-risk PTC patients. Moreover, traditional risk factors considered to favor RAI treatment were not always concordant with the PRSP and may lead to overtreatment.

Low-Temperature Processed Hybrid Organic/Silicon Solar Cells with Power Conversion Efficiency up to 6.5%

Hybrid organic/silicon heterostructures have become of great interest for photovoltaic application due to their promising features (e.g. easy fabrication in a low-temperature process) for cost-effective photovoltaics. This work is focused on solar cells with a hybrid heterojunction between the polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) and n-doped monocrystalline silicon. As semi-transparent top contact, a thin (15 nm) Au layer was employed. Devices with different P3HT thicknesses were processed by spin-casting and compared with a reference Au/n-Si Schottky diode solar cell.

The current density-voltage (J-V) measurements of the hybrid devices show a significant increase in open-circuit voltage (VOC) from 0.29 V up to 0.50 V for the best performing hybrid devices compared to the Schottky diode reference, while the short-circuit current density (JSC) does not change significantly. The increased VOC indicates that P3HT effectively reduces the reverse electron current into the gold contact. The wavelength-dependent JSC measurements show a decreased JSC in the wavelength range of P3HT absorption. This is related to the reduced JSC generation in silicon not being compensated by JSC generation in P3HT. It is concluded that the charge generation in P3HT is less efficient than in silicon.

After a thermal annealing of the hybrid P3HT/silicon solar cells, we achieved power conversion efficiencies (PCE) (AM1.5 illumination) up to 6.5% with VOC of 0.52 V, JSC of 18.6 mA/cm² and a fill factor (FF) of 67%. This is more than twice the efficiency of the reference Schottky diode.

Inattentional blindness increased with augmented reality surgical navigation

BACKGROUND

Augmented reality (AR) surgical navigation systems, designed to increase accuracy and efficiency, have been shown to negatively impact on attention. We wished to assess the effect "head-up" AR displays have on attention, efficiency, and accuracy, while performing a surgical task, compared with the same information being presented on a submonitor (SM).

METHODS

Fifty experienced otolaryngology surgeons (n = 42) and senior otolaryngology trainees (n = 8) performed an endoscopic surgical navigation exercise on a predissected cadaveric model. Computed tomography-generated anatomic contours were fused with the endoscopic image to provide an AR view. Subjects were randomized to perform the task with a standard endoscopic monitor with the AR navigation displayed on an SM or with AR as a single display. Accuracy, task completion time, and the recognition of unexpected findings (a foreign body and a critical complication) were recorded.

RESULTS

Recognition of the foreign body was significantly better in the SM group (15/25 [60%]) compared with the AR alone group (8/25 [32%]; p = 0.02). There was no significant difference in task completion time (p = 0.83) or accuracy (p = 0.78) between the two groups.

CONCLUSION

Providing identical surgical navigation on a SM, rather than on a single head-up display, reduced the level of inattentional blindness as measured by detection of unexpected findings. These gains were achieved without any measurable impact on efficiency or accuracy. AR displays may distract the user and we caution injudicious adoption of this technology for medical procedures.

Localized intraoperative virtual endoscopy (LIVE) for surgical guidance in 16 skull base patients

IMPORTANCE

Previous preclinical studies of localized intraoperative virtual endoscopy-image-guided surgery (LIVE-IGS) for skull base surgery suggest a potential clinical benefit.

OBJECTIVE

The first aim was to evaluate the registration accuracy of virtual endoscopy based on high-resolution magnetic resonance imaging under clinical conditions. The second aim was to implement and assess real-time proximity alerts for critical structures during skull base drilling.

DESIGN AND SETTING

Patients consecutively referred for sinus and skull base surgery were enrolled in this prospective case series.

PARTICIPANTS

Five patients were used to check registration accuracy and feasibility with the subsequent 11 patients being treated under LIVE-IGS conditions with presentation to the operating surgeon (phase 2).

INTERVENTION

Sixteen skull base patients were endoscopically operated on by using image-based navigation while LIVE-IGS was tested in a clinical setting.

MAIN OUTCOME AND MEASURES

Workload was quantitatively assessed using the validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire.

RESULTS

Real-time localization of the surgical drill was accurate to ~1 to 2 mm in all cases. The use of 3-mm proximity alert zones around the carotid arteries and optic nerve found regular clinical use, as the median minimum distance between the tracked drill and these structures was 1 mm (0.2-3.1 mm) and 0.6 mm (0.2-2.5 mm), respectively. No statistical differences were found in the NASA-TLX indicators for this experienced surgical cohort.

CONCLUSIONS AND RELEVANCE

Real-time proximity alerts with virtual endoscopic guidance was sufficiently accurate under clinical conditions. Further clinical evaluation is required to evaluate the potential surgical benefits, particularly for less experienced surgeons or for teaching purposes.

Endoscopic endonasal transsphenoidal approach to large and giant pituitary adenomas: institutional experience and predictors of extent of resection

Object

While the use of endoscopic approaches has become increasingly accepted in the resection of pituitary adenomas, limited evidence exists regarding the success of this technique for patients with large and giant pituitary adenomas. This study reviews the outcomes of a large cohort of patients with large and giant pituitary adenomas who underwent endoscopic endonasal transsphenoidal surgery at the authors' institution and focuses on identifying factors that can predict extent of resection and hence aid in developing guidelines and indications for the use of endoscopic endonasal transsphenoidal surgery versus open craniotomy approaches to large and giant pituitary adenomas.

Methods

The authors reviewed 487 patients who underwent endoscopic endonasal transsphenoidal resection of sellar masses. From this group, 73 consecutive patients with large and giant pituitary adenomas (defined as maximum diameter ≥ 3 cm and tumor volume ≥ 10 cm3) who underwent endoscopic endonasal transsphenoidal surgery between January 1, 2006, and June 6, 2012, were included in the study. Clinical presentation, radiological studies, laboratory investigations, tumor pathology data, clinical outcomes, extent of resection measured by volumetric analysis, and complications were analyzed.

Results

The mean preoperative tumor diameter in this series was 4.1 cm and the volume was 18 cm3. The average resection rate was 82.9%, corresponding with a mean residual volume of 3 cm3. Gross-total resection was achieved in 16 patients (24%), near-total in 11 (17%), subtotal in 24 (36%), and partial in 15 (23%). Seventy-three percent of patients experienced improvement in visual acuity, while 24% were unchanged. Visual fields were improved in 61.8% and unchanged in 5.5%. Overall, 27 patients (37%) experienced a total of 32 complications. The most common complications were sinusitis (14%) and CSF leak (10%). Six patients underwent subsequent radiation therapy because of aggressive tumor histopathology. No deaths occurred in this cohort of patients. Statistically significant predictors of extent of resection included highest Knosp grade (p = 0.001), preoperative tumor volume (p = 0.025), preoperative maximum tumor diameter (p = 0.002), hemorrhagic component (p = 0.027), posterior extension (p = 0.001), and sphenoid sinus invasion (p = 0.005).

Conclusions

Endoscopic endonasal transsphenoidal surgery is an effective treatment method for patients with large and giant pituitary adenomas, which results in high (> 80%) rates of resection and improvement in visual function. It is not associated with high rates of major complications and is safe when performed by experienced surgeons. The preoperative Knosp grade, tumor volume, tumor diameter, hemorrhagic components on MRI, posterior extension, and sphenoid sinus invasion may allow a prediction of extent of resection and in these patients a staged operation may be required to maximize extent of resection.