Thoracoscopic left lung S⁹bii subsegmentectomy for an embedded foreign body in the bronchus: a case report

Introduction

Background

The first choice of treatment for bronchial foreign bodies is removal with a bronchoscope. However, in some cases, surgical intervention may be necessary (1-3). It is important to choose the least invasive and most appropriate procedure in surgeries for foreign bodies in the peripheral bronchus.

Rationale and knowledge gap

Segmentectomy has historically been described for benign diseases such as bronchiectasis and has more recently been applied to the treatment of early-stage lung cancer (4). While segmentectomy and subsegmentectomy techniques for benign conditions are well-documented, applying minimally invasive techniques in cases of embedded foreign bodies, particularly those involving significant inflammatory reactions, presents unique technical challenges. The novel aspect of our approach lies in targeting the minimal lung unit that harbors the foreign body, thus limiting parenchymal resection.

Studies from several countries have indicated that early-stage lung cancer treatment is more effective when less-invasive procedures are used. Specifically, these studies suggest that limited removal of pulmonary parenchyma through sublobar resections and minimal surgical trauma via video-assisted thoracic surgery, including robotic-assisted surgery, result in better noncancer outcomes after lung resection (5-8). Studies have reported technical innovations in lung segmentectomy and the usefulness of three-dimensional (3D) imaging-based preoperative planning with a modern 3D computed tomography (CT) workstation to successfully perform such complex lung resection in patients with lung malignancies (9-15). However, the usefulness of 3D imaging in the treatment of bronchial foreign bodies via lung resection has not been reported.

Objective

We report a case where preoperative planning using 3D-CT and innovative surgical techniques for complex segmentectomy were useful in lung resection for a bronchial foreign body. This article is written following the CARE reporting checklist (available at https://vats.amegroups.com/article/view/10.21037/vats-24-12/rc).

Case presentation

A 70-year-old female, non-smoker, with a history of hypertension, accidentally swallowed a dental crown during a dental treatment. An attempt was made to remove the foreign object via bronchoscopy using basket forceps under general anesthesia with tracheal intubation, but was unsuccessful. This case was referred to our department due to an aspirated dental crown lodged in a small anterior branch of an anterior subsegmental branch of the lateral basilar segmental bronchus (S⁹bii) on the left.

Chest radiography revealed the aspirated dental crown in the lower left lung field (Figure 1). Bronchoscopy showed edematous bronchial mucosa, with the dental crown deeply located and not visible (Figure 2A). An attempt to remove the dental crown using basket forceps with fluoroscopic visualization was unsuccessful (Figure 2B). Chest CT showed obstruction of the B⁹bii by the dental crown, leading to peripheral atelectasis in the left S⁹ (Figure 3).

Figure 1 A chest radiograph shows a dental crown in the left lower lung field (arrow).

Figure 2 Bronchoscopic findings. (A) Bronchoscopy shows the edematous bronchial mucosa. A dental crown is deeply located and not visible. (B) Fluoroscopy of the left chest shows a dental crown (arrow), which could not be removed using basket forceps.

Figure 3 A series of chest computed tomography scans demonstrates a lodged dental crown in the subsegmental bronchi in the left lower lobe (B⁹bii) (arrow) and peripheral atelectasis with surrounding ground-glass attenuation (arrowheads) indicating inflammation. L, left.

An S⁹bii subsegmentectomy, the smallest unit of segmental resection to remove the crown, was planned a week after the dental procedure as the patient remained asymptomatic with stable vital signs. The predicted resection volume was calculated to be merely 1% of both lungs. To facilitate the approach to the intersegmental veins, we decided to adopt the lung base-flip technique (9). The key point in this case was that S⁸ and S¹⁰ were attached medially, forming an intersegmental plane, and the hilum of S⁹b could not be reached without dividing this plane (Figure 4).

Figure 4 Pictorial representation of surgical planning for a left S⁹bii subsegmentectomy indicates the steps of the procedure. (A) Surgical planning for approaching the S⁹bii subsegmental hilum. Yellow ellipses on the left image indicate thoracoscopic port placement sites. A green object seen from the bottom of the left lower lobe images represents a dental crown lodged in a peripheral bronchus. White dotted square on the right picture denotes the area detailed in the bottom panel. (B) Sequential surgical step. 1. Exposure of S⁹ hilum: white dashed arrows indicate the border (intersegmental plane) between segments S⁸ and S¹⁰, which is divided during surgery to obtain sufficient exposure of the S⁹ hilum shown on the right. The dotted white circle highlights the focal area for S⁹ hilum exposure. 2. Division of V⁹: blue arrowheads trace the segmental vein (V⁹) slated for division in the planned procedure. 3. Division of B⁹bii: yellow arrowheads trace the subsegmental bronchus (B⁹bii) slated for division in the planned procedure. 4. Division of A⁹bii: red arrowheads trace the subsegmental artery (A⁹bii) slated for division in the planned procedure.

After careful consideration of the surgical options and the associated risks and benefits, the patient and her family expressed their informed consent and appreciation for the minimally invasive approach, emphasizing their desire for a swift recovery and minimal discomfort.

3D CT workstation and segmentectomy planning

At our institution, we use a state-of-the-art 3D-CT reconstruction workstation (Revoras^®, Ziosoft, Inc., Tokyo, Japan) with a segmentectomy planning function. This planning tool provides specific 3D views tailored to the surgeon, showing the structures in the lungs being divided, along with the stumps and the dissected intersegmental planes. Before the preoperative conference, the primary surgeon or trainees prepare sequential images displaying vascular or bronchial stumps in a simulated surgical view. These images are then presented at the preoperative conference to demonstrate the segmental anatomical features, including branching patterns, anomalies, and the order of surgical sequences (Figure 4).

The 3D-CT planning process involves several key steps: (I) Image acquisition: high-resolution CT scans of the patient’s thorax are obtained. (II) 3D reconstruction: using the Revoras^® software, these scans are reconstructed into detailed 3D models. (III) Segmentation and annotation: the primary surgeon, a training surgeon, or a trained radiologist annotates the relevant anatomical structures, including bronchi, vessels, and any anomalies. (IV) Simulation of surgical steps: the software simulates the surgical steps, showing the structures to be divided and the resulting stumps. (V) Preoperative conference: the sequential images are presented to the surgical team to discuss and finalize the surgical plan. This detailed preoperative planning ensures that the surgical team has a comprehensive understanding of the patient’s unique anatomy, which is critical for executing a precise and minimally invasive procedure. By sharing these detailed models and simulations, we can anticipate and address potential challenges, ensuring a smooth intraoperative experience.

Port placement

Our standard port placement for thoracoscopic lower lobe procedures involves the following: anterior ports in the 5th and 6th intercostal spaces for the primary surgeon, a posterior port in the 7th intercostal space for an assistant surgeon, and a middle port in the 8th intercostal space for the thoracoscope. For upper lobe procedures, the ports are positioned one intercostal space caudal to the lower lobe placement. In this particular case, we shifted all ports slightly posteriorly to optimize access to the subsegmental bronchovascular structures, without changing the intercostal spaces used. This adjustment was made to accommodate the patient’s specific anatomical considerations and the location of the foreign body.

Surgery

Video 1 demonstrates the surgery and its preoperative planning. We divided the pulmonary ligament, identified the lower pulmonary vein, and lifted the lung base. As per our planning, the central intersegmental plane between S⁸ and S¹⁰ was divided using a hook-shaped cautery and a bipolar energy device (ENSEAL™ X1 Curved Jaw, Johnson & Johnson, USA), which enabled us to reach the subsegmental vessels and bronchi of S⁹b located deep inside.

V⁹ was identified and divided using an energy device with central-side ligation. Deep to the divided vein, B⁹bii was identified and divided with scissors after ligating both the peripheral and central sides with 2-0 silk sutures. A⁹bii was identified even deeper to the bronchus, which was divided using an energy device with central-side ligation.

Indocyanine green (ICG) was injected intravenously to identify and mark the peripheral intersegmental planes, which were divided using staplers (ECHELON FLEX™ Powered Stapler, Johnson & Johnson). The dental crown was successfully removed with the subsegmental lung specimen (Figure 5). A sealing test using saline showed no air leakage. Since this case had obstructive inflammation preoperatively, we covered the bronchial stump and segmental resection surface with pericardial fat pad reinforced with fibrin glue.

Figure 5 Images of the resected left S⁹bii subsegment. (A) Fluoroscopic radiograph of the resected specimen shows a dental crown (arrow). (B) Macroscopic image of the resected specimen shows a lodged dental crown (arrow) in the B⁹bii subsegmental bronchus (arrowheads), which was opened in a back table.

Postoperative course

The patient’s postoperative recovery was uneventful, with no air leakage after surgery. The chest tube was removed on postoperative day 2, and the patient was discharged home on day 5 following our standard procedures. In her follow-up visit at 1 year after surgery, she reported no symptoms and her chest CT scan showed good expansion of the remaining lung lobes.

Ethical statement

All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from the patient for the publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

Discussion

Key findings

This case demonstrates the crucial role of proper surgical planning in achieving the least extent of lung resection through a minimally invasive surgical approach, especially when treating benign diseases such as bronchial foreign bodies. Our approach highlights the importance of (I) having a thorough knowledge of individual anatomy, and (II) choosing the appropriate surgical approach to ensure safety during the procedure in the deep subsegmental hilum.

Strengths and limitations

We adopted the “3D-S” strategy to enhance perioperative communication among our surgical team, which is pivotal for intricate thoracic procedures. This strategy is comprised of four key elements—development, demonstration, discussion, and sharing—which collectively contribute to a comprehensive understanding and execution of the surgical plan (16). By developing a 3D model from the CT images, the complex anatomical landscape can be meticulously visualized, with a clear assessment of the individual hilar structure, allowing for a strategic approach to the surgical site. This visualization aids the surgical team in demonstrating and discussing the operative strategy in depth, ensuring a consensus-driven and transparent procedure.

While 3D imaging has been widely reported for segmental and subsegmental resections in lung cancer and other thoracic surgeries, the novelty in our case lies in the application of these techniques specifically for the removal of a bronchial foreign body. Using our state-of-the-art 3D-CT workstation (Revoras^®, Ziosoft, Inc., Tokyo, Japan), we implemented precise 3D imaging-based segmentectomy planning based on the “3D-S” concept. This detailed preoperative planning method has not been previously reported in the context of bronchial foreign body removal, highlighting the innovative aspect of our approach.

The success of this approach relied heavily on the collaboration between various specialties. Radiologists played a crucial role in generating high-quality 3D reconstructions and providing detailed anatomical insights during our weekly multidisciplinary tumor board meeting or on a case-by-case basis. Thoracic surgeons used these models to plan the surgical approach meticulously, identifying critical structures and potential challenges. Anesthesiologists were involved in preoperative discussions to optimize patient management during surgery. This interdisciplinary collaboration ensured that each team member understood the surgical plan and could contribute their expertise to achieve the best possible outcome.

However, the inherent limitations of this process must be acknowledged. The accuracy of 3D models depends on the quality of CT imaging and the precision of the software for reconstruction. Variations in imaging quality can impact the detail and reliability of the 3D models, potentially affecting surgical planning. Additionally, lung plasticity, especially in its deflated state, can pose challenges in maintaining direct correspondence between preoperative imaging and intraoperative anatomy.

The adoption of these advanced techniques and technologies requires significant time investment and resources. Access to high-quality CT imaging, advanced software for 3D reconstruction, and a skilled interdisciplinary team may not be readily available in all surgical settings. The technical expertise needed to interpret and utilize 3D models effectively demands substantial training and experience. Surgeons must be proficient in both the use of 3D imaging tools and minimally invasive surgical techniques, which involves a steep learning curve.

While the integration of these technologies can significantly enhance surgical precision and outcomes, it is crucial to balance these benefits with practical considerations. Institutions must evaluate the cost-effectiveness of implementing such advanced technologies and ensure that the necessary infrastructure and training programs are in place. Furthermore, the time required for detailed preoperative planning may not always be feasible in emergency situations. By acknowledging these limitations and challenges, we aim to provide a balanced view that aids readers in evaluating the applicability of these methods in their practice. Understanding the resource requirements and technical expertise needed for these advanced procedures can help guide their integration into clinical practice, ultimately improving patient care.

Explanations of findings

Surgery planning with the 3D-S concept in a collaborative and comprehensive manner is crucial in this case. The 3D-CT images developed by our surgeons afforded all team members, and crucially, the patient, a clear rationale for the surgical intervention, a thorough grasp of the foreign body’s anatomical context, and a roadmap for addressing the complexities encountered during surgery.

We acknowledge the challenge of lung plasticity, particularly the potential loss of correspondence between 3D-CT imaging created in the inflated state and the actual structure during surgery in its deflated state. To address this, we focus on specific landmarks that remain consistent regardless of the lung’s inflation status: (I) Order and direction of segmental and subsegmental broncho-vascular branches: we carefully map the branching patterns and directions of the bronchi and vessels preoperatively to guide our dissection. (II) Relationships between near-side and far-side structures: we consider the positional relationships between structures on the front and back sides. For instance, knowing that a targeted bronchus is behind the corresponding artery (or vice versa) helps us locate the bronchus after dividing the artery, as they are approximated in the peripheral area. (III) Relationships between central-segmental and peripheral-segmental structures: we use the fan-shaped sector model where two radii represent the intersegmental planes along pulmonary veins, and the arc represents the lung surface. The central structures (segmental bronchi and arteries) run through the middle of this sector from the center to the periphery. By using these consistent anatomical landmarks and the appropriate orientation of 3D-CT images, we can navigate the complexities introduced by lung plasticity effectively. This combination of strategies ensures accurate correspondence between preoperative planning and intraoperative anatomy.

Specifically, in this patient, we were required to adequately expose the fan-shaped sector of S⁹ to access the subsegmental bronchovascular branches of S⁹bii. The utility of the established lung base-flip technique (9), also referred to as the ligamentum-based and the fissure-opposite approaches (17,18), in this case cannot be overstated. By adopting this method, we facilitated an enhanced approach to the intersegmental veins (radii of the sector), allowing a more precise resection. Although the division of the attachment of the S⁸ and S¹⁰ is a routine part of the procedure, we emphasize that the lung base-flip approach allowed us to easily divide the central S⁸-S¹⁰ plane at the beginning of hilar dissection and properly manipulate the complex hilar structures for S⁹bii subsegmentectomy.

Comparison with similar researches

When bronchoscopic removal of a bronchial foreign body is unsuccessful, bronchotomy is traditionally considered the optimal surgical option to preserve pulmonary parenchyma (3). However, in this case, a lung resection was favored over bronchotomy for several reasons: (I) the foreign body’s peripheral position within the lung made it inaccessible; (II) inflammation of the tissues surrounding the foreign body, including both the involved bronchus and the peripheral lung parenchyma, as indicated by bronchoscopic and CT findings, raised concerns about the high risk of postoperative complications, such as anastomotic leakage of the bronchotomy; and (III) a volumetric analysis revealed that the volume of lung tissue to be resected was minimal, thus making subsegmentectomy a viable option for this patient who had no underlying lung disease.

These considerations led to the conclusion that subsegmentectomy was the most suitable procedure, allowing complete removal of the foreign body while preserving as much lung tissue as possible.

Implications and actions needed

The successful removal of a bronchial foreign body through thoracoscopic subsegmentectomy, aided by 3D-CT planning and the lung base-flip technique, underscores the versatility of advanced thoracic surgical techniques. These methods, developed through extensive experience in a variety of thoracic surgeries, can be adapted to manage different conditions, both malignant and benign. The key insights and technical expertise gained from these minimally invasive procedures can be broadly applied to enhance surgical outcomes across a range of thoracic interventions. To integrate these advancements into routine practice, action steps include establishing comprehensive training programs, assessing patient outcomes rigorously, ensuring the availability of advanced imaging technologies, and fostering interdisciplinary cooperation for the management of complex cases.

Through comprehensive training programs, surgeons will acquire a high level of technical expertise, familiarity with advanced thoracoscopic techniques, and proficiency in the use of 3D-CT imaging and reconstruction tools, which involves a significant learning curve. These programs should include: (I) Hands-on workshops: practical sessions on the use of 3D-CT software and thoracoscopic equipment. (II) Simulation training: use of 3D models and virtual reality to simulate the surgical procedure and enhance spatial understanding. (III) Mentorship and collaboration: opportunities for junior surgeons to learn from experienced thoracic surgeons through mentorship programs and collaborative surgeries. (IV) Continuing medical education: regular updates and courses to keep surgeons informed about the latest advancements in thoracic surgery and imaging technologies.

Ensuring the availability of advanced imaging technologies and trained personnel is essential for replicating this approach in other institutions. Investments in technology and training infrastructure will be necessary to make such precision surgeries more accessible. By addressing these areas, the techniques described in this case report can be successfully adopted in other settings, potentially improving outcomes for patients with complex thoracic conditions.

Broader implications and alternative approaches

This case illustrates the sophisticated surgical technique and expertise required for successful thoracoscopic subsegmentectomy. While a simple wedge resection guided by palpation or intraoperative imaging might be feasible in some cases, the relatively deep location of the foreign body and the surrounding inflammatory reaction, in this case, necessitated a more precise approach. The peripheral atelectasis served as a useful localization marker, but the potential difficulty in palpating the foreign body due to inflammation warranted intraoperative fluoroscopic localization. Intraoperative fluoroscopic localization of the foreign body might be a viable solution to this issue. Additionally, navigational bronchoscopy could potentially address similar cases in the future. This case highlights the need for flexible surgical strategies tailored to each patient’s specific circumstances. While our approach demonstrated the utility of advanced imaging and precise surgical techniques, simpler methods such as wedge resection or navigational bronchoscopy could be considered depending on the specific clinical scenario.

Conclusions

In this case report, we have detailed the use of thoracoscopic left lung S⁹bii subsegmentectomy to remove an embedded dental crown. Our approach underscores the utility of advanced surgical techniques, which, while honed in the context of various thoracic surgeries, are broadly applicable to both benign and malignant conditions. By leveraging detailed preoperative planning and precise surgical techniques, we achieved a successful outcome with minimal impact on lung parenchyma.

This case highlights the potential for these advanced techniques to be applied more broadly within thoracic surgery. They offer significant benefits in terms of minimizing operative morbidity and enhancing postoperative recovery. Our findings suggest precision surgery, supported by comprehensive preoperative planning and interdisciplinary collaboration, can improve outcomes for patients with various thoracic conditions.

Acknowledgments

Funding: None.

Footnote

Reporting Checklist: The authors have completed the CARE reporting checklist. Available at https://vats.amegroups.com/article/view/10.21037/vats-24-12/rc

Peer Review File: Available at https://vats.amegroups.com/article/view/10.21037/vats-24-12/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://vats.amegroups.com/article/view/10.21037/vats-24-12/coif). T.E. serves as an unpaid editorial board member of Video-Assisted Thoracic Surgery from September 2023 to August 2025. The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from the patient for the publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Ng J, Kim S, Chang B, et al. Clinical features and treatment outcomes of airway foreign body aspiration in adults. J Thorac Dis 2019;11:1056-64. [Crossref] [PubMed]
2. Bajaj D, Sachdeva A, Deepak D. Foreign body aspiration. J Thorac Dis 2021;13:5159-75. [Crossref] [PubMed]
3. De Lesquen H, Cardinale M, Bergez M, et al. Foreign body removal by a lung-sparing bronchotomy. Multimed Man Cardiothorac Surg 2022; [PubMed]
4. Jensik RJ, Faber LP, Milloy FJ, et al. Segmental resection for lung cancer. A fifteen-year experience. J Thorac Cardiovasc Surg 1973;66:563-72. [Crossref] [PubMed]
5. Altorki N, Wang X, Kozono D, et al. Lobar or Sublobar Resection for Peripheral Stage IA Non-Small-Cell Lung Cancer. N Engl J Med 2023;388:489-98. [Crossref] [PubMed]
6. Saji H, Okada M, Tsuboi M, et al. Segmentectomy versus lobectomy in small-sized peripheral non-small-cell lung cancer (JCOG0802/WJOG4607L): a multicentre, open-label, phase 3, randomised, controlled, non-inferiority trial. Lancet 2022;399:1607-17. [Crossref] [PubMed]
7. Boffa DJ, Dhamija A, Kosinski AS, et al. Fewer complications result from a video-assisted approach to anatomic resection of clinical stage I lung cancer. J Thorac Cardiovasc Surg 2014;148:637-43. [Crossref] [PubMed]
8. Hristov B, Eguchi T, Bains S, et al. Minimally Invasive Lobectomy Is Associated With Lower Noncancer-specific Mortality in Elderly Patients: A Propensity Score Matched Competing Risks Analysis. Ann Surg 2019;270:1161-9. [Crossref] [PubMed]
9. Eguchi T, Miura K, Hamanaka K, et al. Robotic segmentectomy using a lung base-flip approach. JTCVS Tech 2022;15:174-6. [Crossref] [PubMed]
10. Eguchi T, Miura K, Hamanaka K, et al. Adoption of Robotic Core Technology in Minimally Invasive Lung Segmentectomy J Pers Med 2022;12:1417. Review. [Crossref] [PubMed]
11. Eguchi T, Sato T, Shimizu K. Technical Advances in Segmentectomy for Lung Cancer: A Minimally Invasive Strategy for Deep, Small, and Impalpable Tumors. Cancers (Basel) 2021;13:3137. [Crossref] [PubMed]
12. Hamanaka K, Miura K, Eguchi T, et al. Harnessing 3D-CT Simulation and Planning for Enhanced Precision Surgery: A Review of Applications and Advancements in Lung Cancer Treatment. Cancers (Basel) 2023;15:5400. [Crossref] [PubMed]
13. Nakazawa S, Shimizu K, Kawatani N, et al. Right upper lobe segmentectomy guided by simplified anatomic models. JTCVS Tech 2020;4:288-97. [Crossref] [PubMed]
14. Shimizu K, Nakazawa S, Nagashima T, et al. 3D-CT anatomy for VATS segmentectomy. J Vis Surg 2017;3:88. [Crossref] [PubMed]
15. Yutaka Y, Sato T, Matsushita K, et al. Three-dimensional Navigation for Thoracoscopic Sublobar Resection Using a Novel Wireless Marking System. Semin Thorac Cardiovasc Surg 2018;30:230-7. [Crossref] [PubMed]
16. Eguchi T, Shimura M. Tailored Practical Simulation Training in Robotic Surgery: A New Educational Technology. Ann Thorac Surg Short Rep. 2023;1:474-8. [Crossref]
17. Gonzalez M, Federici S, Perentes J. Uniportal VATS S9 segmentectomy: The ligamentum-based approach. Multimed Man Cardiothorac Surg 2021; [Crossref] [PubMed]
18. Rakovich G. Thoracoscopic posterobasal segmentectomy, right lower lobe. Multimed Man Cardiothorac Surg 2020; [Crossref] [PubMed]