Project description:Background: Electromagnetic navigational bronchoscopy (ENB) and robotic-assisted bronchoscopy (RB) require a high degree of decision-making and psychomotor skill. Cognitive load theory is the overall effort expended by individuals in response to a task and is closely related to the usability of devices for medical procedures. High cognitive workload leads to poor surgical outcomes and represents a bottleneck for learning that affects performance.Objective: To analyze the cognitive load associated with ENB and RB in experienced ENB practitioners learning RB.Methods: Six experienced ENB bronchoscopists performed ENB and RB on a human cadaver model of peripheral pulmonary nodules. To assess cognitive load, we used the Surgery Task Load Index (SURG-TLX) and biometric changes. The SURG-TLX questionnaire was given to the provider after every peripheral pulmonary nodule biopsy with ENB and RB. Pupillary dilation and screen changes were continuously measured throughout the procedure for each biopsy attempt to collect biometric measures of cognitive load. Procedural time and biopsy outcome were also recorded.Results: Forty procedures (ENB and RB) were analyzed. Task complexity (23%) and mental demand (21.4%) were the highest contributors to cognitive load in ENB and RB. The cumulative SURG-TLX was significantly lower for the RB (69.25 vs. 101.25; P < 0.01). Total procedure time was greater for ENB (6.7 min; SD 1.5) compared with RB (4.4 min; SD 1.5; P = 0.01). Pupillary diameter was similar across the modalities (RB vs. ENB), but the diameter was higher during the biopsy portion (4.25 mm) than the navigation portion (4.01 mm).Conclusion: The intrinsic cognitive load of RB was highly manageable by existing ENB practitioners, and in this study, RB appeared to be less mentally demanding. Future development and training should focus on task complexity and mental demand for RB. The biopsy portion, regardless of bronchoscopic modality, should be a focus for education and training.
Project description:Objectives:Over 25% of the high-risk population screened for lung cancer have an abnormal computed tomography (CT) scan. Conventionally, these lesions have been biopsied with CT guidance with a high diagnostic yield. Electromagnetic navigational bronchoscopy (ENB) with transbronchial biopsy has emerged as a technology that improves the diagnostic sensitivity of conventional bronchoscopic biopsy. It has been used to biopsy lung lesions, due to the low risk of pneumothorax. It is, however, a new technology that is expensive and its role in the diagnosis of the solitary pulmonary nodule (SPN) is yet to be determined. The purpose of this study was to evaluate the diagnostic yield of CT-guided biopsy (CTB) following non-diagnostic ENB biopsy and identify characteristics of the lesion that predicts a low diagnostic yield with ENB, to ensure appropriate use of ENB in the evaluation of SPN. Materials and Methods:One hundred and thirty-five lung lesions were biopsied with ENB from January 2017 to August 2019. Biopsies were considered diagnostic if pathology confirmed malignancy or inflammation in the appropriate clinical and imaging setting. We evaluated lesions for several characteristics including size, lobe, and central/peripheral distribution. The diagnostic yield of CTB in patients who failed ENB biopsies was also evaluated. Logistic regression was used to identify factors likely to predict a non-diagnostic ENB biopsy. Result:Overall, ENB biopsies were performed in 135 patients with solitary lung lesions. ENB biopsies were diagnostic in 52% (70/135) of the patients. In 23 patients with solitary lung lesions, CTBs were performed following a non-diagnostic ENB biopsy. The CTBs were diagnostic in 87% of the patients (20/23). ENB biopsies of lesions <21.5 mm were non-diagnostic in 71% of cases (42/59); 14 of these patients with non-diagnostic ENB biopsies had CTBs, and 86% of them were diagnostic (12/14). ENB biopsies of lesions in the lower lobes were non- diagnostic in 59% of cases (35/59); 12 of these patients with non-diagnostic ENB biopsies had CTBs, and 83% were diagnostic (10/12). ENB biopsies of lesions in the outer 2/3 were non-diagnostic in 57% of cases (50/87); 21 of these patients with non-diagnostic ENB biopsies had CTBs, and 86% were diagnostic (18/21). Conclusion:CTBs have a high diagnostic yield even following non-diagnostic ENB biopsies. Lesions <21.5 mm, in the outer 2/3 of the lung, and in the lower lung have the lowest likelihood of a diagnostic yield with ENB biopsies. Although CTBs have a slightly higher pneumothorax rate, these lesions would be more successfully diagnosed with CTB as opposed to ENB biopsy, in the process expediting the diagnosis and saving valuable medical resources.
Project description:PurposeResearchers are currently seeking relevant lung cancer biomarkers in order to make informed decisions regarding therapeutic selection for patients in so-called "precision medicine." However, there are challenges to obtaining adequate lung cancer tissue for molecular analyses. Furthermore, current molecular testing of tumors at the genomic or transcriptomic level are very indirect measures of biological response to a drug, particularly for small molecule inhibitors that target kinases. Kinase activity profiling is therefore theorized to be more reflective of in vivo biology than many current molecular analysis techniques. As a result, this study seeks to prove the feasibility of combining a novel minimally invasive biopsy technique that expands the number of lesions amenable for biopsy with subsequent ex vivo kinase activity analysis.MethodsEight patients with lung lesions of varying location and size were biopsied using the novel electromagnetic navigational bronchoscopy (ENB) technique. Basal kinase activity (kinomic) profiles and ex vivo interrogation of samples in combination with tyrosine kinase inhibitors erlotinib, crizotinib, and lapatinib were performed by PamStation 12 microarray analysis.ResultsKinomic profiling qualitatively identified patient specific kinase activity profiles as well as patient and drug specific changes in kinase activity profiles following exposure to inhibitor. Thus, the study has verified the feasibility of ENB as a method for obtaining tissue in adequate quantities for kinomic analysis and has demonstrated the possible use of this tissue acquisition and analysis technique as a method for future study of lung cancer biomarkers.ConclusionsWe demonstrate the feasibility of using ENB-derived biopsies to perform kinase activity assessment in lung cancer patients.
Project description:BackgroundAdditional data regarding the ability of navigational bronchoscopy (NB) to provide sufficient material for programmed death-ligand 1 (PD-L1) expression is needed. We performed a retrospective study of NB cases at our institution to determine performance of NB in providing adequate samples for PD-L1.MethodsWe conducted a retrospective review of all consecutive NB procedures performed at our institution from January 1, 2018 to August 4, 2020 that involved biopsies of a lung nodule/mass with a diagnosis of non-small cell lung cancer (NSCLC). The primary outcome was adequacy of material for PD-L1 testing. All procedural, demographic, and diagnostic data were collected. The association of factors with PD-L1 adequacy was evaluated with rate ratios (RR) using modified Poisson regression models with robust standard errors.ResultsA total of 102 NB procedures with a diagnosis of NSCLC were performed over a 2-year period. The mean [standard deviation (SD)] nodule size was 25.0 [interquartile range (IQR), 18.0-32.0] mm and 57.8% (59/102) had a bronchus sign; 73% (68/93, 9 missing data) of samples were adequate for PD-L1 testing. Radial endobronchial ultrasound (REBUS) was utilized in 99% (101/102) of biopsies; a concentric or eccentric view was observed in 78.2% (79/101) and 16.8% (17/101), respectively. Transbronchial biopsy (TBBX) was performed in 92.2% (94/102). Only 4% (4/102) of cases required additional biopsies with either computed tomography (CT) guided transthoracic or surgical biopsies due to insufficient bronchoscopy tissue. No factors were predictive of PD-L1 adequacy in regression models.ConclusionsNB demonstrated good performance in obtaining adequate samples for PD-L1 testing. Only 4% of patients required additional procedures for more tissue when clinically indicated. However, additional study is needed to validate these results against surgical resection specimens.
Project description:The peripheral pulmonary nodule offers unique challenges to the clinician, especially in regards to diagnostic approach. Quite often the etiology of the nodule is spurious, though the specter of malignancy drives accurate classification of the nodule. Diagnostic approaches range in degrees of invasiveness, accuracy, and morbidity. Bronchoscopic access to these nodules had been plagued by low reported yields, especially in fluoroscopically invisible nodules. Navigational bronchoscopy, however, allowed more accurate access to peripheral nodules while maintaining a low morbidity, and thus reshaped the historic diagnostic algorithms. Though navigational bronchoscopy was initially associated with electromagnetic navigation, newer approaches to navigation and new technologies provide enthusiasm that yield can improve. In this article we will provide a historical approach to navigational bronchoscopy, from its origins to its current state, and we will discuss developing technology and its potential role in the evolving paradigm of the peripheral nodule biopsy.
Project description:RationaleElectromagnetic navigation bronchoscopy using superDimension/Bronchus System is a novel method to increase diagnostic yield of peripheral and mediastinal lung lesions.ObjectivesA prospective, open label, single-center, pilot study was conducted to determine the ability of electromagnetic navigation bronchoscopy to sample peripheral lung lesions and mediastinal lymph nodes with standard bronchoscopic instruments and demonstrate safety.MethodsElectromagnetic navigation bronchoscopy was performed using the superDimension/Bronchus system consisting of electromagnetic board, position sensor encapsulated in the tip of a steerable probe, extended working channel, and real-time reconstruction of previously acquired multiplanar computed tomography images. The final distance of the steerable probe to lesion, expected error based on the actual and virtual markers, and procedure yield was gathered.Measurements60 subjects were enrolled between December 2004 and September 2005. Mean navigation times were 7 +/- 6 min and 2 +/- 2 min for peripheral lesions and lymph nodes, respectively. The steerable probe tip was navigated to the target lung area in all cases. The mean peripheral lesions and lymph nodes size was 22.8 +/- 12.6 mm and 28.1 +/- 12.8 mm. Yield was determined by results obtained during the bronchoscopy per patient.ResultsThe yield/procedure was 74% and 100% for peripheral lesions and lymph nodes, respectively. A diagnosis was obtained in 80.3% of bronchoscopic procedures. A definitive diagnosis of lung malignancy was made in 74.4% of subjects. Pneumothorax occurred in two subjects.ConclusionElectromagnetic navigation bronchoscopy is a safe method for sampling peripheral and mediastinal lesions with high diagnostic yield independent of lesion size and location.
Project description:BackgroundThe endobronchial diagnosis of peripheral lung lesions suspected of lung cancer remains a challenge from a navigation as well as an adequate tissue sampling perspective. Cone-beam computed tomography (CBCT) guidance is a relatively new technology and allows for 3-dimensional imaging confirmation as well as navigation and biopsy guidance, but, also involves radiation. This study investigates how radiation exposure and diagnostic accuracy in the CBCT-guided navigation bronchoscopy evolves with increasing experience, and, with a specific tailoring of CBCT and fluoroscopic imaging protocols towards the procedure.Patients and methodsIn this observational clinical trial, all 238 consecutive patients undergoing a CBCT-guided navigation bronchoscopy from the start of our CBCT-guided navigation bronchoscopy program (December 2017) until June 2020 were included. Procedural dose characteristics and diagnostic accuracy are reported as a function of time.ResultsProcedural radiation exposure as measured by the dose area product initially was 47.5 Gy·cm2 (effective dose: 14.3 mSv) and gradually reduced to 25.4 Gy·cm2 (5.8 mSv). The reduction in fluoroscopic dose area product was highest, from 19.0 Gy·cm2 (5.2 mSv) to 2.2 Gy·cm2 (0.37 mSv, 88% reduction), despite a significant increase of fluoroscopy time. The diagnostic accuracy of navigation bronchoscopy increased from 72% to 90%.ConclusionA significant learning effect can be seen in the radiation safety and diagnostic accuracy of a CBCT-guided and augmented fluoroscopy-guided navigation bronchoscopy. With increasing experience and tailoring of imaging protocols to the procedure, the procedural accuracy improved, while the effective dose for patients and staff was reduced.
Project description:BackgroundWe assessed the performance of Electromagnetic navigational bronchoscopy (ENB) as a standalone diagnostic technique and the performance of different sampling tools used during the procedure.MethodsWe recruited 160 consecutive patients who underwent ENB for peripheral lung lesions (PLL) at a tertiary care centre. The diagnostic performance of ENB and sampling tools was assessed using a logistic regression model and a ROC-curve in which the dependent variable was diagnostic success. A multivariate model was built to predict diagnostic success before performing ENB to select the best candidates for the procedure.ResultsMost patients with PLLs in the study were male (65%), with a mean age of 67.9 years. The yield was 66% when the most common techniques were used together as suction catheter + transbronchial biopsy forceps (TBBx) + bronchoalveolar lavage + bronchial washing (p < 0.001) and increased to 69% when transbronchial needle aspiration (TBNA) and cytology brush were added (p < 0.001). Adding diagnostic techniques such as TBBx and TBNA resulted in an increase in diagnostic performance, with a statistically significant trend (p = 0.002). The logistic model area-under the ROC-curve for diagnostic success during ENB was 0.83 (95% CI:0.75-0.90; p < 0.001), and a logit value ≥ 0.12 was associated with ≥ 50% probability of diagnostic success.ConclusionsENB, as a stand-alone diagnostic tool for the evaluation of PLLs when performed by experienced operators using a multi-modality technique, has a good diagnostic yield. The probability of having a diagnostic ENB could be assessed using the proposed model.
Project description:To estimate the body temperature (BT) of seven dinosaurs Gillooly, Alleen, and Charnov (2006) used an equation that predicts BT from the body mass and maximum growth rate (MGR) with the latter preserved in ontogenetic growth trajectories (BT-equation). The results of these authors evidence inertial homeothermy in Dinosauria and suggest that, due to overheating, the maximum body size in Dinosauria was ultimately limited by BT. In this paper, I revisit this hypothesis of Gillooly, Alleen, and Charnov (2006). I first studied whether BTs derived from the BT-equation of today's crocodiles, birds and mammals are consistent with core temperatures of animals. Second, I applied the BT-equation to a larger number of dinosaurs than Gillooly, Alleen, and Charnov (2006) did. In particular, I estimated BT of Archaeopteryx (from two MGRs), ornithischians (two), theropods (three), prosauropods (three), and sauropods (nine). For extant species, the BT value estimated from the BT-equation was a poor estimate of an animal's core temperature. For birds, BT was always strongly overestimated and for crocodiles underestimated; for mammals the accuracy of BT was moderate. I argue that taxon-specific differences in the scaling of MGR (intercept and exponent of the regression line, log-log-transformed) and in the parameterization of the Arrhenius model both used in the BT-equation as well as ecological and evolutionary adaptations of species cause these inaccuracies. Irrespective of the found inaccuracy of BTs estimated from the BT-equation and contrary to the results of Gillooly, Alleen, and Charnov (2006) I found no increase in BT with increasing body mass across all dinosaurs (Sauropodomorpha, Sauropoda) studied. This observation questions that, due to overheating, the maximum size in Dinosauria was ultimately limited by BT. However, the general high inaccuracy of dinosaurian BTs derived from the BT-equation makes a reliable test of whether body size in dinosaurs was ultimately limited by overheating impossible.