The authors have no acknowledgments.

Following Danish law, an educational study without the participation of patients does not require ethical approval.
1. Handling of the scope
<ol>
	<li>Hold the bronchoscope in the left hand with the left thumb on the steering lever and the left forefinger on the suction button. Use the right hand to hold the distal part of the bronchoscope.</li>
	<li>Holding the scope with a straight arm and wrist, so the suction button is pointing directly forward and the steering lever is in the neutral position, is defined as the neutral position or 0&#176;. By twisting the wrist, turn the scope from the neutral position/0&#176;.</li>
	<li>Move the thumb up and down the lever to flex and extend the distal end of the endoscope. Move the wrist and hands, not the arm and body.</li>
</ol>
2. Structured progress: angle of the scope and the four landmarks
<ol>
	<li>Enter the airways either through the mouth or nostrils. Pass the vocal cords and enter the trachea.</li>
	<li>Find the four landmarks systematically from landmarks 1 to 4 and note the correct angle of the endoscope in each position (Table 1). 
	NOTE: The four landmarks approach is designed in a memorable way to decrease the cognitive load for novel bronchoscopists. It is based on a pairing between the angle of the bronchoscope and how to access the different lobes/landmarks. The approach, therefore, provides novice trainees with a basic training tool to navigate through the bronchial maze. As an example, by knowing if the bronchoscope is held at a 90&#176; angle to the right, the correct position to inspect the right upper lobe can be determined. When visualizing the lobe or landmark, one should defer from the designated angle to inspect the individual segments.</li>
	<li>Find the segments chronologically from 1-10, the right side first, then the left side according to the four landmarks.</li>
</ol>
3. Systematic bronchoscopy: the four landmarks approach
<ol>
	<li>Landmark 1: The carina with the right and the left main bronchus as seen from the trachea (Figure 2)
	<ol>
		<li>Locate the bronchoscope in the distal part of the trachea at a 0&#176; angle-the neutral position. If the orientation is lost, go back to landmark 1 to reorientate.</li>
	</ol>
	</li>
	<li>Landmark 2: Right segments 1, 2, and 3 (upper lobe) (Figure 3)
	<ol>
		<li>Turn the endoscope 90&#176; to the right while at the same time flexing the distal end of the bronchoscope upward by pushing the left thumb down to investigate the upper lobe. This landmark resembles the Mercedes star.</li>
		<li>When visualizing the Mercedes star, defer from the 90&#176; angle to inspect segments 1, 2, and 3.</li>
	</ol>
	</li>
	<li>Landmark 3: Right segments 4 and 5 (middle lobe) plus 6, 7, 8, 9, and 10 (lower lobe) (Figure 4)
	<ol>
		<li>Move on to the bronchus intermedius by placing the distal end of the endoscope at a 45&#176; angle to the right to see segments 4 and 5 (numbers from the lateral side at an oblique angle).</li>
		<li>Again, defer from the 45&#176; angle to inspect segments 4 and 5. Go back to the 45&#176; angle and extend the tip of the endoscope by pushing the stewing lewer upward with the left thumb to inspect segment 6 (just opposite the middle lobe).</li>
		<li>Turn the scope to a 0&#176; angle and progress to the lower lobe. Segment 7 is located medially, and segments 8, 9, and 10 (numbers from the lateral side at an oblique angle) at the bottom. Defer from the 0&#176; angle to inspect segments 7-10.</li>
	</ol>
	</li>
	<li>Landmark 4: Left segments 1+2, 3, 4, and 5 (upper lobe), plus segments 6, 8, 9, and 10 (lower lobe) (Figure 5)
	<ol>
		<li>Move the bronchoscope to the left main bronchus (90&#176; angle to the left), upward to see the upper lobe, and downward to see the lower lobe.</li>
		<li>Keep the scope at a 90&#176; angle to inspect the left upper lobe with the lingula. Defer from the 90&#176; angle to inspect segments 1+2 and 3 (left upper lobe) and segments 4 and 5 (lingula).</li>
		<li>Go back to the left main bronchus, turn the scope to a 45&#176; angle, and extend the end of the bronchoscope to inspect segment 6, which is opposite segments 4 and 5 (lingula).</li>
		<li>Turn the scope to a 0&#176; angle to visualize the lower lobe with segments 8, 9, and 10. Defer from the 0&#176; angle to inspect the segments. 
		NOTE: There is no segment 7 on the left side, as this area is filled out by the heart. Segments 4 and 5 plus 8, 9, and 10 follow the same numbering as for the right side, and are numbered from the lateral side at an oblique angle (Figure 6).</li>
	</ol>
	</li>
</ol>

Flexible Bronchoscopy for Novice Bronchoscopists

<ol>
	<li>Bray, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+cancer+statistics+2018:+GLOBOCAN+estimates+of+incidence+and+mortality+worldwide+for+36+cancers+in+185+countries.">Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries.</a> CA: A Cancer Journal for Clinicians. 68 (6), 394-424 (2018).</li><li>Andolfi, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+bronchoscopy+in+the+diagnosis+of+early+lung+cancer:+a+review.">The role of bronchoscopy in the diagnosis of early lung cancer: a review.</a> Journal of Thoracic Disease. 8 (11), 3329-3337 (2016).</li><li>Hsu, L. H., Liu, C. C., Ko, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Education+and+experience+improve+the+performance+of+transbronchial+needle+aspiration:+a+learning+curve+at+a+cancer+center.">Education and experience improve the performance of transbronchial needle aspiration: a learning curve at a cancer center.</a> Chest. 125 (2), 532-540 (2004).</li><li>Ouellette, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+safety+of+bronchoscopy+in+a+pulmonary+fellowship+program.">The safety of bronchoscopy in a pulmonary fellowship program.</a> Chest. 130 (4), 1185-1190 (2006).</li><li>Stather, D. R., MacEachern, P., Chee, A., Dumoulin, E., Tremblay, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trainee+impact+on+procedural+complications:+An+analysis+of+967+consecutive+flexible+bronchoscopy+procedures+in+an+interventional+pulmonology+practice.">Trainee impact on procedural complications: An analysis of 967 consecutive flexible bronchoscopy procedures in an interventional pulmonology practice.</a> Respiration. International Review of Thoracic Diseases. 85 (5), 422-428 (2013).</li><li>McGaghie, W. C., Issenberg, S. B., Cohen, E. R., Barsuk, J. H., Wayne, D. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Medical+education+featuring+mastery+learning+with+deliberate+practice+can+lead+to+better+health+for+individuals+and+populations.">Medical education featuring mastery learning with deliberate practice can lead to better health for individuals and populations.</a> Academic Medicine. 86 (11), e8-e9 (2011).</li><li>Konge, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Establishing+pass/fail+criteria+for+bronchoscopy+performance.">Establishing pass/fail criteria for bronchoscopy performance.</a> Respiration; International Review of Thoracic Diseases. 83 (2), 140-146 (2012).</li><li>Konge, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reliable+and+valid+assessment+of+clinical+bronchoscopy+performance.">Reliable and valid assessment of clinical bronchoscopy performance.</a> Respiration; International Review of Thoracic Diseases. 83 (1), 53-60 (2012).</li><li>Colt, H. G., Crawford, S. W., Galbraith 3rd, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Virtual+reality+bronchoscopy+simulation:+A+revolution+in+procedural+training.">Virtual reality bronchoscopy simulation: A revolution in procedural training.</a> Chest. 120 (4), 1333-1339 (2001).</li><li>Cold, K. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+structured+progress+to+measure+competence+in+flexible+bronchoscopy.">Using structured progress to measure competence in flexible bronchoscopy.</a> Journal of Thoracic Disease. 12 (11), 6797-6805 (2020).</li><li>Cold, K. M., Konge, L., Clementsen, P. F., Nayahangan, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simulation-based+mastery+learning+of+flexible+bronchoscopy:+Deciding+factors+for+completion.">Simulation-based mastery learning of flexible bronchoscopy: Deciding factors for completion.</a> Respiration; International Review of Thoracic Diseases. 97 (2), 160-167 (2019).</li><li>Nayahangan, L. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identifying+technical+procedures+in+pulmonary+medicine+that+should+be+integrated+in+a+simulation-based+curriculum:+A+national+general+needs+assessment.">Identifying technical procedures in pulmonary medicine that should be integrated in a simulation-based curriculum: A national general needs assessment.</a> Respiration; International Review of Thoracic Diseases. 91 (6), 517-522 (2016).</li><li>Konge, L., Arendrup, H., von Buchwald, C., Ringsted, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+performance+in+multiple+simulated+scenarios+to+assess+bronchoscopy+skills.">Using performance in multiple simulated scenarios to assess bronchoscopy skills.</a> Respiration; International Review of Thoracic Diseases. 81 (6), 483-490 (2011).</li><li>Kennedy, C. C., Maldonado, F., Cook, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simulation-based+bronchoscopy+training:+systematic+review+and+meta-analysis.">Simulation-based bronchoscopy training: systematic review and meta-analysis.</a> Chest. 144 (1), 183-192 (2013).</li><li>Sealy, W. C., Connally, S. R., Dalton, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Naming+the+bronchopulmonary+segments+and+the+development+of+pulmonary+surgery.">Naming the bronchopulmonary segments and the development of pulmonary surgery.</a> The Annals of Thoracic Surgery. 55 (1), 184-188 (1993).</li><li>Naur, T. M. H., Nilsson, P. M., Pietersen, P. I., Clementsen, P. F., Konge, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simulation-based+training+in+flexible+bronchoscopy+and+endobronchial+ultrasound-guided+transbronchial+needle+aspiration+(EBUS-TBNA):+A+systematic+review.">Simulation-based training in flexible bronchoscopy and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA): A systematic review.</a> Respiration; International Review of Thoracic Diseases. 93 (5), 355-362 (2017).</li><li>Sanz-Santos, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Systematic+compared+with+targeted+staging+with+endobronchial+ultrasound+in+patients+with+lung+cancer.">Systematic compared with targeted staging with endobronchial ultrasound in patients with lung cancer.</a> The Annals of Thoracic Surgery. 106 (2), 398-403 (2018).</li><li>Colella, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+competence+in+simulated+flexible+bronchoscopy+using+motion+analysis.">Assessment of competence in simulated flexible bronchoscopy using motion analysis.</a> Respiration; International Review of Thoracic Diseases. 89 (2), 155-161 (2015).</li><li>Cold, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Automatic+and+objective+assessment+of+motor+skills+performance+in+flexible+bronchoscopy.">Automatic and objective assessment of motor skills performance in flexible bronchoscopy.</a> Respiration; International Review of Thoracic Diseases. 100 (4), 347-355 (2021).</li><li>Follmann, A., Pereira, C. B., Knauel, J., Rossaint, R., Czaplik, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+a+bronchoscopy+guidance+system+for+bronchoscopy+training,+a+randomized+controlled+trial.">Evaluation of a bronchoscopy guidance system for bronchoscopy training, a randomized controlled trial.</a> BMC Medical Education. 19 (1), 430 (2019).</li><li>Nilsson, P. M., Naur, T. M. H., Clementsen, P. F., Konge, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simulation+in+bronchoscopy:+current+and+future+perspectives.">Simulation in bronchoscopy: current and future perspectives.</a> Advances in Medical Education and Practice. 8, 755-760 (2017).</li><li>Strandbygaard, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+structured+four-step+curriculum+in+basic+laparoscopy:+development+and+validation.">A structured four-step curriculum in basic laparoscopy: development and validation.</a> Acta Obstetricia et Gynecologica Scandinavica. 93 (4), 359-366 (2014).</li><li>Konge, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+simulation+centre+at+Rigshospitalet,+Copenhagen,+Denmark.">The simulation centre at Rigshospitalet, Copenhagen, Denmark.</a> Journal of Surgical Education. 72 (2), 362-365 (2015).</li></ol>

The authors have nothing to disclose.

We propose a systematic and complete inspection of the bronchial segments, splitting the bronchoscopy into four landmarks to help guide novice bronchoscopists through the bronchial maze. As more specific guidelines that govern bronchoscopy training are needed14, we propose that our systematic and stepwise approach should be evaluated using three basic outcome measures: DC, SP, and PT. 
DC and PT are established outcome measures and the first used when evaluating broncho...

Lung cancer is the leading cause of cancer mortality1. Flexible bronchoscopy is essential to navigate through the bronchial tree and identify the correct segments for the diagnosis and staging of lung cancer and allocation to the correct treatment for the patient2. Lower yields of diagnostic biopsy material, higher complication rates, and increased patient discomfort are seen in the early part of a trainee&#39;s learning curve3,4,5. To ensure independent/unsupervised practice on patients, satisfactory educational levels must be met. A training modality to ensure basic competence is simulation-based mastery learning, where the trainee practices until proficiency criteria are met6. Several tools have been developed to assess bronchoscopy performance7,8, and the following performance measures have been established: (1) diagnostic completeness (DC)-proportion of visualized segments9; (2) structured progress (SP)-number of segments visited in the correct progression order10; and (3) procedure time (PT)-time from passing through the vocal cords to the end of the procedure9.
Novice bronchoscopists can be confused by the maze, looking like similar bronchi, and several fail to complete a course in simulation-based bronchoscopy11, even though it has been identified as the most important technical procedure to learn in pulmonary medicine12. Therefore, through this protocol, we propose a stepwise, structured progression through the bronchial tree (Figure 1), relying on four landmarks as a guide. We suggest that novice operators should be taught according to this approach to ensure visualization of all the bronchial segments in a structured way, in the shortest amount of time, with correct handling of the scope.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Evis Exera II</td>
			<td>Olympus</td>
			<td>Not provided</td>
			<td>Endoscopy Tower</td>
		</tr>
		<tr>
			<td>BF-Q180 Bronchoscope</td>
			<td>Olympus</td>
			<td>Not provided</td>
			<td>Flexible Bronchoscope</td>
		</tr>
		<tr>
			<td>CLA Broncho Boy</td>
			<td>CLA</td>
			<td>Not provided</td>
			<td>Bronchial Tree Phantom</td>
		</tr>
	</tbody>
</table>

systematic bronchoscopy: the four landmarks approach

Flexible bronchoscopy is a technically difficult procedure and has been identified as the most important procedure that should be integrated into a simulation-based training program for pulmonologists. However, more specific guidelines that govern bronchoscopy training are needed to meet this demand. To ensure patients a competent examination, we propose a systematic, stepwise approach, splitting the procedure into four &#34;landmarks&#34; to support novice endoscopists navigating the bronchial maze. The procedure can be evaluated based on three established outcome measures to ensure a thorough and effective inspection of the bronchial tree: diagnostic completeness, structured progress, and procedure time.
The stepwise approach relying on the four landmarks is used at all simulation centers in Denmark and is being implemented in the Netherlands. To provide instant feedback to novice bronchoscopists when training and to relieve time constraints from consultants, we suggest that future studies should implement artificial intelligence&#160;as a feedback and certification tool when training new bronchoscopists.

The four landmarks approach has been taught at CAMES since 2011, where the simulation-based bronchoscopy course is concluded by passing a finalizing test13. From 2015-2017, 77 participants entered the course, of which only 33 (43%) completed it11. The low completion rate was due to several factors: time constraints, the course not being mandatory, maternity leave, and no protected time to train. Of those who completed the course, 14 (42%) found the most important factor for...

Watch this Scientific Journal Video about Learning Systematic Bronchoscopy in a Simulation-Base Setting at JoVE.com

Author Spotlight: Learning Systematic Bronchoscopy in a Simulation-Base Setting 

Here, we present a protocol to navigate the bronchial maze in a structured manner, splitting the bronchoscopy into a stepwise approach-the four landmarks approach.

Systematic Bronchoscopy: the Four Landmarks Approach

Flexible bronchoscopy is a technically difficult procedure and has been identified as the most important procedure that should be integrated into a ...

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2.1K Views.  University of Copenhagen and the Capital Region of Denmark. Here, we present a protocol to navigate the bronchial maze in a structured manner, splitting the bronchoscopy into a stepwise approach-the four landmarks approach. 

Video: Author Spotlight: Learning Systematic Bronchoscopy in a Simulation-Base Setting 

The Bovine Lung in Biomedical Research: Visually Guided Bronchoscopy, Intrabronchial Inoculation and In Vivo Sampling Techniques

There is an ongoing search for alternative animal models in research of respiratory medicine. Depending on the goal of the research, large animals as models of pulmonary disease often resemble the situation of the human lung much better than mice do. Working with large animals also offers the opportunity to sample the same animal repeatedly over a certain course of time, which allows long-term studies without sacrificing the animals.
The aim was to establish in vivo sampling methods for the use in a bovine model of a respiratory Chlamydia psittaci infection. Sampling should be performed at various time points in each animal during the study, and the samples should be suitable to study the host response, as well as the pathogen under experimental conditions.
Bronchoscopy is a valuable diagnostic tool in human and veterinary medicine. It is a safe and minimally invasive procedure. This article describes the intrabronchial inoculation of calves as well as sampling methods for the lower respiratory tract. Videoendoscopic, intrabronchial inoculation leads to very consistent clinical and pathological findings in all inoculated animals and is, therefore, well-suited for use in models of infectious lung disease. The sampling methods described are bronchoalveolar lavage, bronchial brushing and transbronchial lung biopsy. All of these are valuable diagnostic tools in human medicine and could be adapted for experimental purposes to calves aged 6-8 weeks. The samples obtained were suitable for both pathogen detection and characterization of the severity of lung inflammation in the host.

The Bovine Lung in Biomedical Research: Visually Guided Bronchoscopy, Intrabronchial Inoculation and In Vivo Sampling Techniques

This article describes bronchoscopic techniques in the bovine lung under experimental conditions, i.e. bronchoscopically guided inoculation, bronchoalveolar lavage, bronchial brushing, and transbronchial lung biopsy.

There is an ongoing search for alternative animal models in research of respiratory medicine. Depending on the goal of the research, large animals as ...

Posterior Approach for Debridement of the Psoas Abscess

This method focuses on outlining a safe zone for irrigation and debridement of a psoas abscess through a posterior approach. Initially, an anterior approach to the spine was performed to ensure that the anterior longitudinal ligament and the psoas muscle could be visualized. All the abdominal organs were removed. Subsequently, a posterior approach was performed to remove the paraspinal muscles from L1&#8211;L5. The transverse processes, pars interarticularis and lamina of L1&#8211;L5 were identified. The exiting nerve root was identified between the transverse processes and followed into the substance of the psoas muscle. Using the anterior and posterior approach, the lumbar plexus was isolated from the substance of the psoas muscle. Before and after various steps of dissection, digital photographs were obtained. These images were uploaded into ImageJ and multiple measurements, including the distance between the lateral superior and inferior tip of each TP to the most lateral region of the plexus, the distance between the lateral superior and inferior tip of the TP to the lateral edge of the psoas, and the width of the lumbar plexus were recorded. The safe zone for entering the substance of the psoas muscle was defined between the lateral edge of the psoas muscle and the lateral edge of the lumbar plexus. The relationship of this interval to the tip of the transverse process at each level was measured and reported.

This is a cadaveric study investigating the landmarks for the posterior approach for irrigation and debridement of the psoas abscess. The interval between the transverse processes (TP) was used to access the substance of the psoas muscle.

This method focuses on outlining a safe zone for irrigation and debridement of a psoas abscess through a posterior approach. Initially, an anterior ...

The Microscopic Transcanal Approach in Stapes Surgery Revisited

The microscopic transcanal (aka transmeatal) surgical approach was first described in the 60s, offering a minimally invasive means of reaching the external auditory canal, the middle ear, and epitympanon. Such an approach avoids a retroauricular or endaural skin incision; however, working through a narrow space needs angled microsurgical instruments and specific training in otologic surgery. The transcanal approach restricts the working space; however, it offers a binocular microscopic vision into the middle ear without extended skin incisions and thus, reducing post-operative pain and bleeding. In addition, this minimally invasive approach avoids scar tissue complications, hypoesthesia of the auricle, and potential protrusion of the pinna. Despite its numerous advantages, this method is still not routinely performed by otologic surgeons. Since this minimally invasive technique is more challenging, there is a need for extensive training in order for it to be widely adopted by otologic surgeons. This article provides step-by-step surgical instructions for stapes surgery and reports possible indications, pitfalls, and limitations using this microscopic transcanal technique.

This article describes the microscopic transcanal technique for stapes surgery, providing step-by-step surgical instructions for familiarizing surgeons with this approach.

The microscopic transcanal (aka transmeatal) surgical approach was first described in the 60s, offering a minimally invasive means of reaching the ...

Four-Dimensional Computed Tomography-Guided Valve Sizing for Transcatheter Pulmonary Valve Replacement

The measurements of the right ventricle (RV) and pulmonary artery (PA), for selecting the optimal prosthesis size for transcatheter pulmonary valve replacement (TPVR), vary considerably. Three-dimensional (3D) computed tomography (CT) imaging for device size prediction is insufficient to assess the displacement of the right ventricular outflow tract (RVOT) and PA, which could increase the risk of stent misplacement and paravalvular leak. The aim of this study is to provide a dynamic model to visualize and quantify the anatomy of the RVOT to PA over the entire cardiac cycle by four-dimensional (4D) cardiac CT reconstruction to obtain an accurate quantitative evaluation of the required valve size. In this pilot study, cardiac CT from sheep J was chosen to illustrate the procedures. 3D cardiac CT was imported into 3D reconstruction software to build a 4D sequence which was divided into eleven frames over the cardiac cycle to visualize the deformation of the heart. Diameter, cross-sectional area, and circumference of five imaging planes at the main PA, sinotubular junction, sinus, basal plane of the pulmonary valve (BPV), and RVOT were measured at each frame in 4D straightened models prior to valve implantation to predict the valve size. Meanwhile, dynamic changes in the RV volume were also measured to evaluate right ventricular ejection fraction (RVEF). 3D measurements at the end of the diastole were obtained for comparison with the 4D measurements. In sheep J, 4D CT measurements from the straightened model resulted in the same choice of valve size for TPVR (30 mm) as 3D measurements. The RVEF of sheep J from pre-CT was 62.1 %. In contrast with 3D CT, the straightened 4D reconstruction model not only enabled accurate prediction for valve size selection for TPVR but also provided an ideal virtual reality, thus presenting a promising method for TPVR and the innovation of TPVR devices.

This study assessed a new methodology with a straightened model generated from the four-dimensional cardiac computed tomography sequence to obtain the desired measurements for valve sizing in the application of transcatheter pulmonary valve replacement.

The measurements of the right ventricle (RV) and pulmonary artery (PA), for selecting the optimal prosthesis size for transcatheter pulmonary valve ...

Laparoscopic Radical Antegrade Modular Pancreatosplenectomy via Dorsal-Caudal Artery Approach for Pancreatic Neck-Body Cancer

Laparoscopic radical resection of the pancreatic neck is one of the most complicated radical operations for pancreatic cancer, especially for patients who have had neoadjuvant chemotherapy. Here, we present a technique to perform laparoscopic radical antegrade modular pancreatosplenectomy (L-RAMPS) using the dorsal-caudal artery approach by making full use of the high-definition vision and operation modes of the laparoscope.
The innovation and optimization of this operation are provided in the protocol. Priority should be given to the dorsal resection plane, including the dorsal side of the superior mesenteric artery (SMA), the dorsal side of the pancreatic head, the root of the celiac artery (CeA), the ventral side of the left renal vessels, and the renal hilum. On the condition that the operation for pancreatic neck-body cancer is feasible and safe, the second step is to perform tumor resection en bloc surrounding the SMA and CeA from the caudal to the cephalic side to increase the rate of R0 (radical zero) resection and further prognosis.

Laparoscopic Radical Antegrade Modular Pancreatosplenectomy via Dorsal-Caudal Artery Approach for Pancreatic Neck-Body Cancer

With advancements in laparoscopic techniques, laparoscopic radical antegrade modular pancreatosplenectomy (L-RAMPS) has been widely recognized. However, owing to several technical difficulties in this procedure, the artery-first approach in L-RAMPS still remains uncommon. Here, we developed the dorsal-caudal artery approach for L-RAMPS, which might be safe and beneficial for pancreatic neck tumors.

Laparoscopic radical resection of the pancreatic neck is one of the most complicated radical operations for pancreatic cancer, especially for patients who ...

Investigating Novel Mechanisms of Microvascular Dysfunction in Humans

Intradermal Microdialysis: An Approach to Investigating Novel Mechanisms of Microvascular Dysfunction in Humans

The cutaneous vasculature is an accessible tissue that can be used to assess microvascular function in humans. Intradermal microdialysis is a minimally invasive technique used to investigate mechanisms of vascular smooth muscle and endothelial function in the cutaneous circulation. This technique allows for the pharmacological dissection of the pathophysiology of microvascular endothelial dysfunction as indexed by decreased nitric oxide-mediated vasodilation, an indicator of cardiovascular disease development risk. In this technique, a microdialysis probe is placed in the dermal layer of the skin, and a local heating unit with a laser Doppler flowmetry probe is placed over the probe to measure the red blood cell flux. The local skin temperature is clamped or stimulated with direct heat application, and pharmacological agents are perfused through the probe to stimulate or inhibit intracellular signaling pathways in order to induce vasodilation or vasoconstriction or to interrogate mechanisms of interest (co-factors, antioxidants, etc.). The cutaneous vascular conductance is quantified, and mechanisms of endothelial dysfunction in disease states can be delineated.

Author Spotlight: A Pharmacodissection Approach to Uncover Mechanisms in Cardiovascular Disease Risk Populations 

Intradermal microdialysis is a minimally invasive technique used to investigate microvascular function in health and disease. Both dose-response and local heating protocols can be utilized for this technique to explore mechanisms of vasodilation and vasoconstriction in the cutaneous circulation.

The cutaneous vasculature is an accessible tissue that can be used to assess microvascular function in humans. Intradermal microdialysis is a minimally ...

3D Cephalometric Landmark Annotation Demonstration on Human CBCT Scans

Three-Dimensional Cephalometric Landmark Annotation Demonstration on Human Cone Beam Computed Tomography Scans

Craniofacial cephalometric analysis is a diagnostic tool used for the assessment of the relationship of various bones and soft tissues in the head and face. Cephalometric analysis has been traditionally conducted with the use of 2D radiographs and landmark sets and restricted to size, linear and angular measurements, and 2D relationships. The increasing use of 3D cone beam computed tomography (CBCT) scans in the dental field dictates the need for the evolution to 3D cephalometric analysis, which incorporates shape and a more realistic analysis of longitudinal development in all three planes. This study is a demonstration of 3D cephalometric analysis with the use of a validated set of skeletal tissue landmarks on human CBCT scans. Detailed instructions for the annotation of each landmark on a 3D volume are provided as part of a step-by-step protocol. The generated measurements and 3D coordinates of the landmarks can be exported and used both for clinical and research purposes. The introduction of 3D cephalometric analysis in basic and clinical craniofacial studies will lead to future advancements in the field of craniofacial growth and development.

Author Spotlight: Three-Dimensional Cephalometric Landmark Annotation Demonstration on Human Cone Beam Computed Tomography Scans  

Presented here is a detailed protocol for the conduction of three-dimensional cephalometric analysis with the use of human cone beam computed tomography scans.

Craniofacial cephalometric analysis is a diagnostic tool used for the assessment of the relationship of various bones and soft tissues in the head and ...

Gasless Endoscopic Thyroidectomy via the Trans-Axillary Approach

For patients with early, low-risk papillary thyroid carcinoma, an increasing number are opting for endoscopic thyroid surgery due to its ability to achieve favorable therapeutic outcomes while maintaining excellent cosmetic results. Among the available endoscopic procedures, the Gasless Endoscopic Thyroidectomy Trans-axillary Approach (GETTA) has gained popularity among surgeons. This is attributed to its straightforward cavity construction, spacious operating area, precise visual field exposure, and manageable learning curve. However, few studies have provided detailed descriptions of the specific surgical steps involved in GETTA. Drawing from a synthesis of existing literature and our own clinical expertise, we present a comprehensive outline of the GETTA procedure. This process can be categorized into five distinct stages: positioning and incision planning; establishment of surgical cavities; identification and protection of the recurrent laryngeal nerve, inferior parathyroid gland, and central neck dissection; localization and preservation of the superior laryngeal nerve, superior parathyroid gland, and dissection of the thyroid's superior pole; transection of the thyroid isthmus followed by en bloc resection of the thyroid gland and central neck lymph nodes. The five-step approach of GETTA is easy to learn and can be adapted for resecting both benign and malignant thyroid and parathyroid diseases.

Gasless Endoscopic Thyroidectomy via the Trans-Axillary Approach

This protocol presents the procedure for conducting thyroidectomy using the gasless endoscopic thyroidectomy trans-axillary approach (GETTA).

For patients with early, low-risk papillary thyroid carcinoma, an increasing number are opting for endoscopic thyroid surgery due to its ability to ...

Integrating Transesophageal Ultrasound with an Echoendobronchoscope

Using the Endoscope for Endobronchial Ultrasound in the Esophagus

EUS-B is a procedure using the echoendobronchoscope in the esophagus and stomach. The procedure is a minimally invasive, safe, and feasible approach that pulmonologists can use to visualize and biopsy structures adjacent to the esophagus and stomach. EUS-B gives access to many structures of which some may also be reached by EBUS (mediastinal lymph nodes, lung or pleural tumors, pericardial fluid) while others cannot be reached such as retroperitoneal lymph nodes, ascites, and lesions in the liver, pancreas or left adrenal gland. The procedure is a pulmonologist- and patient- friendly version of the gastroenterologists' EUS using the thin EBUS endoscope that the pulmonologist already masters. Thus EUS-B training should be easy and a natural continuation of EBUS. With the patient under conscious sedation and in the supine position, the echoendoscope is introduced either through the nostril or mouth into the oropharynx. Then the patient is encouraged to swallow while the endoscope is slowly bent posteriorly and introduced into the esophagus and stomach. Using the ultrasonic image, the operator identifies the six landmarks by EUS-B and EUS: the left liver lobe, abdominal aorta (with the celiac trunk and superior mesenteric artery), left adrenal gland, and mediastinal lymph node stations 7, 4L, and 4R. Biopsies can be taken from suspected lesions under real-time ultrasonographic guidance- fine needle aspiration (EUS-B-FNA) using a technique similar to that used with EBUS-TBNA. The biopsy order is M1b-M1a-N3-N2-N1-T (M = metastasis, N = lymph node, T = tumor) to avoid iatrogenic upstaging. Pre- and post-procedural observation is similar to that of bronchoscopy. EUS-B is safe and feasible in the hands of experienced interventional pulmonologists and provides a significant expansion of the diagnostic possibilities in providing safe, fast, and thorough diagnosis and staging of lung cancer.

Author Spotlight: Advancing Biopsy Techniques with Transesophageal Ultrasound

Transesophageal ultrasound (EUS-B) is a safe and feasible procedure using the echoendobronchoscope (EBUS) in esophagus and stomach. After identifying six anatomical landmarks, additional structures can be identified and biopsied, sparing subsequent diagnostic sessions. Thus, EUS-B is an ideal continuation of bronchoscopy and EBUS in diagnosing lung cancer and other diseases.

EUS-B is a procedure using the echoendobronchoscope in the esophagus and stomach. The procedure is a minimally invasive, safe, and feasible approach that ...

Laparoscopic Duodenum-Preserving Pancreatic Head Resection via Inferior Infracolic Approach: A Surgical Approach for Benign Lesions

Minimally invasive pancreatic resections are gaining popularity despite being technically demanding. However, in contrast to laparoscopic pancreatoduodenectomy (LPD), laparoscopic duodenum-preserving pancreatic head resection (LDPPHR) has not yet obtained wide acceptance. This could be attributed to the technical challenges involved in preserving the blood supply of the duodenum and bile duct.
This study describes and demonstrates all the steps of LDPPHR. A 48-year-old woman was diagnosed with a 3.0 cm x 2.5 cm pancreatic head cystic mass, which was detected unexpectedly. The surgery was performed using the 3D laparoscopy via an inferior infracolic approach. The operation lasted approximately 310 min with 100 mL of blood loss. Postoperatively, the patient experienced no complications and was discharged 5 days later. Pathology revealed intraductal papillary mucinous neoplasms.
LDPPHR via an inferior infracolic approach is feasible and safe when performed by experienced surgeons in selected patients with thin mesenteric fat layers. The described technique for LDPPHR via inferior infracolic approach should be well standardized and performed at high-volume centers with experienced surgeons in both open and laparoscopic pancreatology.

This article provides a whole technical process of laparoscopic duodenum-preserving pancreatic head resection via an inferior infracolic approach. This is a surgical approach for benign tumors without intraoperative fluorescence image guidance.