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Dive into the research topics where David Fielding is active.

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Featured researches published by David Fielding.


Internal Medicine Journal | 2008

Biopsy site selection for endobronchial ultrasound guide‐sheath transbronchial biopsy of peripheral lung lesions

David Fielding; P. J. Robinson; N. Kurimoto

Background: Choice of biopsy method for peripheral lung lesions is usually between CT‐guided fine‐needle aspiration biopsy (CT FNA) and bronchoscopy. Endobronchial ultrasound guide‐sheath biopsy (EBUS GS) is a new method to improve the yield of bronchoscopy. Guidance on which lesions would be appropriate for either method is needed. The aim of the study was to compare the diagnostic yields and pneumothorax rate of EBUS GS and CT FNA in terms of the location of the lesion needing biopsy, in particular, whether the lesion is touching the pleura.


European Respiratory Journal | 2013

Rapid cytological analysis of endobronchial ultrasound-guided aspirates in sarcoidosis

M. Plit; A. Havryk; Alan Hodgson; Daniel James; Andrew Field; Sonia Carbone; Allan R. Glanville; Farzad Bashirzadeh; Anna Chay; Justin Hundloe; Rebecca Pearson; David Fielding

Rapid on-site evaluation (ROSE) of endobronchial ultrasound-guided transbronchial needle aspirates (EBUS-TBNA) has not been compared to final detailed cytological analysis in patients with suspected sarcoidosis. To assess the diagnostic accuracy of EBUS-TBNA with ROSE in patients with suspected sarcoidosis, a prospective two-centre study performed EBUS-TBNA with ROSE of cellular material followed by transbronchial lung biopsy (TBLB) and endobronchial biopsy (EBB). The diagnostic accuracy of EBUS-TBNA with ROSE was compared to the final cytological assessment and to TBLB and EBB. Analysis confirmed 49 out of 60 cases of sarcoidosis. ROSE sensitivity was 87.8% (specificity 91%, positive predictive value 97.7%). ROSE slide interpretation in combination with the final fixed slide and cell block preparations had a sensitivity of 91.8% (specificity 100%, positive predictive value 100%). 67% of patients were confirmed as having sarcoidosis on TBLB and 29% on EBB. Interobserver agreement between cytotechnologists and pathologists was very good (&kgr;=0.91, 95% CI 0.80–1.0 and &kgr;=0.91, 95% CI 0.79–1.0, respectively). EBUS-TBNA with ROSE has high diagnostic accuracy and interobserver agreement and informs the bronchoscopist in theatre whether additional diagnostic procedures need to be undertaken. EBUS-TBNA with ROSE should therefore be considered as the first-line investigation of sarcoidosis. Rapid on-site evaluation of EBUS-TBNA should be first-line investigation in sarcoidosis http://ow.ly/nT9Mx


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2013

High specificity of combined narrow band imaging and autofluorescence mucosal assessment of patients with head and neck cancer

Phan Nguyen; Farzad Bashirzadeh; Robert Hodge; Julie Agnew; Camile S. Farah; Edwina Duhig; Belinda E. Clarke; Joanna Perry-Keene; David Botros; Ian B. Masters; David Fielding

The purpose of this study was to evaluate combined autofluorescence (AF) and narrow band imaging (NBI) for detection of mucosal lesions additional to known primary head and neck cancers and to determine impact on management.


Chest | 2012

Optical Differentiation Between Malignant and Benign Lymphadenopathy by Grey Scale Texture Analysis of Endobronchial Ultrasound Convex Probe Images

Phan Nguyen; Farzad Bashirzadeh; Justin Hundloe; Olivier Salvado; Nicholas Dowson; Robert S. Ware; Ian B. Masters; Manoj Bhatt; Aravind S. Ravi Kumar; David Fielding

BACKGROUND Morphologic and sonographic features of endobronchial ultrasound (EBUS) convex probe images are helpful in predicting metastatic lymph nodes. Grey scale texture analysis is a well-established methodology that has been applied to ultrasound images in other fields of medicine. The aim of this study was to determine if this methodology could differentiate between benign and malignant lymphadenopathy of EBUS images. METHODS Lymph nodes from digital images of EBUS procedures were manually mapped to obtain a region of interest and were analyzed in a prediction set. The regions of interest were analyzed for the following grey scale texture features in MATLAB (version 7.8.0.347 [R2009a]): mean pixel value, difference between maximal and minimal pixel value, SEM pixel value, entropy, correlation, energy, and homogeneity. Significant grey scale texture features were used to assess a validation set compared with fluoro-D-glucose (FDG)-PET-CT scan findings where available. RESULTS Fifty-two malignant nodes and 48 benign nodes were in the prediction set. Malignant nodes had a greater difference in the maximal and minimal pixel values, SEM pixel value, entropy, and correlation, and a lower energy (P < .0001 for all values). Fifty-one lymph nodes were in the validation set; 44 of 51 (86.3%) were classified correctly. Eighteen of these lymph nodes also had FDG-PET-CT scan assessment, which correctly classified 14 of 18 nodes (77.8%), compared with grey scale texture analysis, which correctly classified 16 of 18 nodes (88.9%). CONCLUSIONS Grey scale texture analysis of EBUS convex probe images can be used to differentiate malignant and benign lymphadenopathy. Preliminary results are comparable to FDG-PET-CT scan.


Respirology | 2013

Physician-performed ultrasound can accurately screen for a vulnerable intercostal artery prior to chest drainage procedures

Matthew Salamonsen; K. Dobeli; David McGrath; Craig Readdy; Robert S. Ware; Karin Steinke; David Fielding

Laceration of the intercostal artery during pleural procedures is a rare but serious complication. This study evaluates the utility of thoracic ultrasound (US) to screen for a vulnerable vessel compared with the gold standard computed tomography (CT).


Respiration | 2012

Thoracic ultrasound demonstrates variable location of the intercostal artery

Matthew Salamonsen; Samantha Ellis; Eldho Paul; Karin Steinke; David Fielding

Background: Ultrasound (US) guidance is advocated to reduce complications from thoracocentesis or intercostal catheter (ICC) insertion. Although imaging of the intercostal artery (ICA) with Doppler US has been reported, current thoracic guidelines do not advocate this, and bleeding from a lacerated ICA continues to be a rare but serious complication of thoracocentesis or ICC insertion. Objectives: It was the aim of this study to describe a method to visualise the ICA at routine US-guided thoracocentesis and map its course across the posterior chest wall. Method: The ICA was imaged in 22 patients undergoing US-guided thoracocentesis, at 4 positions across the back to the axilla. Its location, relative to the overlying rib, was calculated as the fraction of the intercostal space (ICS) below the inferior border of that rib. Results: An ICA was identified in 74 of 88 positions examined. The ICA migrated from a central ‘vulnerable’ location within the ICS near the spine (0.28, range 0.21–0.38; p < 0.001) towards the overlying rib (0.08, range 0.05–0.11; p < 0.001) in the axilla. Conclusions: The ICA can be visualised with US and is more exposed centrally within the ICS in more posterior positions; however, there is a marked variation between individuals, such that the ICA may lie exposed in the ICS even as far lateral as the axilla. Future studies need to identify which patients are at risk for a ‘low-lying’ ICA to further define the role of US imaging of the ICA during thoracocentesis or ICC insertion.


Chest | 2014

Novel Use of Pleural Ultrasound Can Identify Malignant Entrapped Lung Prior to Effusion Drainage

Matthew Salamonsen; Ada K. C Lo; Arnold C.T. Ng; Farzad Bashirzadeh; W. Wang; David Fielding

BACKGROUND The presence of entrapped lung changes the appropriate management of malignant pleural effusion from pleurodesis to insertion of an indwelling pleural catheter. No methods currently exist to identify entrapped lung prior to effusion drainage. Our objectives were to develop a method to identify entrapped lung using tissue movement and deformation (strain) analysis with ultrasonography and compare it to the existing technique of pleural elastance (PEL). METHODS Prior to drainage, 81 patients with suspected malignant pleural effusion underwent thoracic ultrasound using an echocardiogram machine. Images of the atelectatic lower lobe were acquired during breath hold, allowing motion and strain related to the cardiac impulse to be analyzed using motion mode (M mode) and speckle-tracking imaging, respectively. PEL was measured during effusion drainage. The gold-standard diagnosis of entrapped lung was the consensus opinion of two interventional pulmonologists according to postdrainage imaging. Participants were randomly divided into development and validation sets. RESULTS Both total movement and strain were significantly reduced in entrapped lung. Using data from the development set, the area under the receiver-operating curves for the diagnosis of entrapped lung was 0.86 (speckle tracking), 0.79 (M mode), and 0.69 (PEL). Using respective cutoffs of 6%, 1 mm, and 19 cm H2O on the validation set, the sensitivity/specificity was 71%/85% (speckle tracking), 50%/85% (M mode), and 40%/100% (PEL). CONCLUSIONS This novel ultrasound technique can identify entrapped lung prior to effusion drainage, which could allow appropriate choice of definitive management (pleurodesis vs indwelling catheter), reducing the number of interventions required to treat malignant pleural effusion.


Internal Medicine Journal | 2012

Prospective randomised trial of endobronchial ultrasound-guide sheath versus computed tomography-guided percutaneous core biopsies for peripheral lung lesions

David Fielding; C. Chia; Phan Nguyen; Farzad Bashirzadeh; Justin Hundloe; I. G. Brown; Karin Steinke

Aim:  To determine diagnostic rate, complications and patient tolerability of endobronchial ultrasound‐guide sheath (EBUS‐GS) and computed tomography (CT)‐guided percutaneous core biopsy for peripheral lung lesions.


Chest | 2013

A New Instrument to Assess Physician Skill at Thoracic Ultrasound, Including Pleural Effusion Markup

Matthew Salamonsen; David McGrath; Geoff Steiler; Robert S. Ware; Henri G. Colt; David Fielding

BACKGROUND To reduce complications and increase success, thoracic ultrasound is recommended to guide all chest drainage procedures. Despite this, no tools currently exist to assess proceduralist training or competence. This study aims to validate an instrument to assess physician skill at performing thoracic ultrasound, including effusion markup, and examine its validity. METHODS We developed an 11-domain, 100-point assessment sheet in line with British Thoracic Society guidelines: the Ultrasound-Guided Thoracentesis Skills and Tasks Assessment Test (UGSTAT). The test was used to assess 22 participants (eight novices, seven intermediates, seven advanced) on two occasions while performing thoracic ultrasound on a pleural effusion phantom. Each test was scored by two blinded expert examiners. Validity was examined by assessing the ability of the test to stratify participants according to expected skill level (analysis of variance) and demonstrating test-retest and intertester reproducibility by comparison of repeated scores (mean difference [95% CI] and paired t test) and the intraclass correlation coefficient. RESULTS Mean scores for the novice, intermediate, and advanced groups were 49.3, 73.0, and 91.5 respectively, which were all significantly different (P < .0001). There were no significant differences between repeated scores. CONCLUSIONS Procedural training on mannequins prior to unsupervised performance on patients is rapidly becoming the standard in medical education. This study has validated the UGSTAT, which can now be used to determine the adequacy of thoracic ultrasound training prior to clinical practice. It is likely that its role could be extended to live patients, providing a way to document ongoing procedural competence.


Respirology | 2014

Achieving competency in bronchoscopy: Challenges and opportunities

David Fielding; Fabien Maldonado; Septimiu D. Murgu

Bronchoscopy education is undergoing significant changes in step with other medical and surgical specialties that seek to incorporate simulation‐based training and objective measurement of procedural skills into training programmes. Low‐ and high‐fidelity simulators are now available and allow learners to gain fundamental bronchoscopy skills in a zero‐risk environment. Testing trainees on simulators is currently possible by using validated assessment tools for both essential bronchoscopy and endobronchial ultrasound skills, and more tools are under development for other bronchoscopic techniques. Educational concepts including the ‘flipped classroom’ model and problem‐based learning exercises are increasingly used in bronchoscopy training programmes. These learner‐centric teaching modalities require well‐trained educators, which is possible thorough the expansion of existing faculty development programmes.

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Farzad Bashirzadeh

Royal Brisbane and Women's Hospital

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Phan Nguyen

Royal Adelaide Hospital

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Ali I. Musani

University of Colorado Denver

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Matthew Salamonsen

Royal Brisbane and Women's Hospital

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Justin Hundloe

Royal Brisbane and Women's Hospital

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Karin Steinke

Royal Brisbane and Women's Hospital

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Lakshmy Nandakumar

Royal Brisbane and Women's Hospital

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Aravind S. Ravi Kumar

Royal Brisbane and Women's Hospital

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