Transoral Access Research Articles

Setup and initial testing of an endoscope manipulator system for assistance in transoral endoscopic surgery.

Purpose For the treatment of malignant diseases of the oral cavity and the larynx, a total or partial resection is the standard therapy, while in special cases chemo- and/or external radiation therapy is considered. Transoral access reduces trauma and hospitalization time. Transoral surgery is usually executed using external microscopic imaging. Therefore, the microscope is placed in the visual line of the opening of the mouth and throat. However, specific anatomical structures like the posterior commissure (dorsal end of the vocal cords) are not visible in these procedures. An endoscopic approach can improve this problem. We introduce a new prototype system for endoscopic assisted transoral surgery. Methods Based on clinical observation and discussions with professional users and surgeons, the clinical need was identified and specified. A general concept or an endoscopic manipulator to assist microlaryngeal surgery was designed. For that a steerable rigid endoscope was combined with an actuator that allows translational and rotational movement. A quick release fastener was designed allowing for fast change of the endoscope and independence from its shape and type. The actuator was fixed on a commercially available, semi-active medical holding arm for easy positioning. The holder can be fixed to the standard rails of the surgical table. The piezoelectric drives integrated in the actuator are activated with a foot pedal. This allows easy and fast fine positioning, while the hands are free to perform the surgery with standard instruments for microlaryngeal surgery. Results A prototype of the system for endoscopic assisted transoral surgery was developed. The entire technical setup was tested in terms of usability and performance in a simulated surgical scenario. A basic phantom, representing the throat and vocal cords was created and placed on a surgical table. The system was installed on the table and the clinical workflow of a simulated endoscopic assisted surgery on the vocal cords was performed. The performance of the setup and the procedure success was evaluated by clinical users. Conclusion Fixture of the system on the surgical table is fast and easy due to its low weight and compact design. The medical holder allows a fast initial positioning of the system in front of the phantom patient. An easy insertion and removal of the endoscope was realized using the quick release fastener. The developed endoscope fixation is universally adaptable and not limited to a single type of endoscope. The piezoelectric drives, combined with the foot pedal, allow a precise placement and readjustment of the endoscope during surgery. The use of a multi view endoscope enables a variable view on the surgical situs. The size and shape of the whole setup offer excellent access to the targeted structures. The development was classified beneficial by the clinical users.

Transnasal adenoidectomy in mucopolysaccharidosis

BackgroundMucopolysaccharide (MPS) diseases are a heterogeneous group of inherited, metabolic disorders characterized by accumulation of partially degraded glycosaminoglycans (GAG) in multiple organ systems. Due to accumulation in the airway, patients often present with multilevel airway obstruction and obstructive sleep apnoea (OSA). Adenotonsillar surgery leads to a significant improvement in the severity of OSA in MPS patients. However, access to secure the airway and for conventional surgery can be challenging, due to limited neck extension, macroglossia and reduced mouth opening. This study was undertaken to evaluate the role of transnasal microdebridement and radiofrequent plasma ablation (Coblation) in adenoidectomy to treat OSA in patients with MPS and restricted airway access. MethodsA retrospective case review was performed including patients with MPS undergoing adenoidectomy for OSA in the period between June 2015 and March 2017. In all cases, either a microdebrider (Gyrus Diablo) or a Coblation wand (EVAC70, Smith&Nephew) was used via a transnasal approach guided by nasendoscopy. The primary outcome was effect upon OSA, measured by sleep oximetry and parental report of benefit. The secondary outcomes were surgical complications and risk factors for persistent OSA after surgery. ResultsA total of nine patients were identified with a mean age of 9 years (range 3–14 years) at surgery. Post-operative sleep study data was available for eight patients (8/9). Six patients (6/8) had improvement in 4% oxygen desaturation index (ODI-4) with a mean of 8.11 pre-operatively (range 2.69–14.0) and 4.99 postoperatively (range 0.68–8.48). ODI-4 did not improve in two (2/8) patients. Irrespective of sleep oximetry results, improvement in OSA-related symptoms was noted by all parents postoperatively. No risk factors for persistent OSA were identified. Furthermore, no complications were noted in this cohort. ConclusionTransnasal Coblation and Microdebrider adenoidectomy is a safe and effective surgical treatment for OSA in patients with Mucopolysaccharidosis and adenoidal hypertrophy. As lifespan increases for patients with the Mucopolysaccharidoses, greater emphasis is being given to optimising airway management over the longer-term. This technical note describes the novel application of endoscopic techniques for the management of primary adenoidal hypertrophy when transoral access is restricted, or to debulk recurrent disease that would be challenging to remove via the standard transoral route.

Hybrid techniques and patients' safety in implementing transoral sublingual thyroidectomy.

Cosmetic advantages and minimally invasive aspects become more and more important for patients undergoing thyroidectomy. We report on our personal experience and conceptual design in dealing with approaches to the thyroid gland, which we were the first to describe. We report on ideas and experiences concerning its implementation. Our own experiences and considerations in the process of finding an endoscopic minimally invasive access in thyroidectomy are compared in a systematic review with the available literature on minimally invasive or endoscopic thyroid surgery. We describe our failures and risk assessment. Our analysis of the literature on minimally invasive thyroidectomy and our own experiences lead us to the conclusion that using different hybrid technologies during the implementation of endoscopic procedures in thyroid surgery can be helpful and could improve patients' safety. A combination of transoral endoscopic and non-transoral techniques might be a useful safer, but more traumatizing alternative for implementation. Several studies show the feasibility of the transoral access in thyroid surgery. We believe that the implementation of these new procedures as routine surgery in specialized centers must be carefully considered and discussed. The transoral access seems to be less invasive than other extracollar endoscopic accesses in thyroid surgery. For a sublingual single-access routine surgery, better instruments are needed. The vestibular access is possible with standard instruments. Using hybrid technologies for implementation should not be considered as a failure. The transoral thyroidectomy can be a safe method in the hand of experienced surgeons. We expect this hybrid technique to play a major part in further spreading endoscopic transoral thyroid surgery.

Evaluation Criteria and Surgical Technique for Transoral Access to the Thyroid Gland: Experimental Study

ABSTRACTBackground: The development of endoscopic techniques motivated surgeons to search for alternative and more cosmetic approaches for thyroid and parathyroid surgery. Several variations of transoral access to the anterior neck areas were applied in recent years. One of them is a premandibular access proposed by Nakajo et al, it is performed through the oral vestibule by creating the working space by means of the lifting method. Materials and methods: Nineteen unfixed human cadavers were used to develop the endoscopic access to the thyroid gland and surgical techniques of its resection. The Nakajo access was modified by altering the spatial location of the working instruments, resulting in practically no impact on the cosmetic outcome but providing a more comfortable operation for the thyroid gland. We determined evaluation criteria of the cadaver model before initiation of the experimental trial. Parameters that influence on alteration of these criteria were registered. Results: Of the 19 operated objects, the first 7 were used to practice the access technique from the incision in the oral vestibule to the thyroid gland in order to evaluate the possibility of endoscopic dissection of the important anatomical. The next 12 surgeries were carried out by manipulating the thyroid gland in the settings maximally close to real. Access implied good cosmetic results, less surgical traumatic due to a smaller area of detachment of the musculocutaneous flap. Conclusions: The achieved results show feasibility of introducing the described modification of transoral thyroidectomy into clinical practice.

Laparoscopic-Assisted Transgastric ERCP: A Single-Institution Experience

Background Laparoscopic-assisted transgastric endoscopic retrograde cholangiopancreatography (LAERCP) is used for treatment in patients after Roux-en-Y gastric bypass (RYGB), where transoral access to the biliary tree is not possible. We describe our technique and experience with this procedure. Methods Electronic medical record search was performed from September 2012 to January 2016, identifying patients who underwent LAERCP per operative records. Charts were reviewed for demographic, clinical, and outcomes data. Results Sixteen patients were identified. Average time since bypass was 6.9 years, and length of stay was 3.7 days. Five patients underwent simultaneous cholecystectomy. Eleven patients, or 43%, had cholecystectomy more than 2 years previously. ERCP with sphincterotomy was completed in 15 of 16 patients (94%). Our technique involves access to the bypassed stomach via a laparoscopically placed 15 mm port. We observed one major complication of post-ERCP necrotizing pancreatitis. No minor complications nor mortalities were seen in our series. Conclusion Biliary obstruction can occur many years after RYGB and cholecystectomy. Our findings suggest that RYGB patients may be at a higher risk of primary CBD stone formation. LAERCP is a reliable option for common bile duct (CBD) clearance; our technique of LAERCP is technically simple and associated with low complication rate, making it appealing to surgeons not trained in advanced laparoscopy.

Transoral endoscopic thyroidectomy using vestibular approach: updates and evidences.

Recently, natural orifice transluminal endoscopic surgery (NOTES) has been applied in thyroid surgery with transoral access. The benefit of transoral endoscopic thyroidectomy is the potential for scar-free surgery. However, there are many concerns over some aspects, such as infection, recurrent laryngeal nerve injury, and oncological outcome. In this paper, we have reviewed the development history and the current clinical evidence of this innovative surgery. We conclude that the transoral endoscopic thyroidectomy vestibular approach (TOETVA) is feasible and can be considered no longer an experimental operation.

Trans-oral miniature X-ray radiation delivery system with endoscopic optical feedback

PurposeSurgery, chemo- and/or external radiation therapy are the standard therapy options for the treatment of laryngeal cancer. Trans-oral access for the surgery reduces traumata and hospitalization time. A new trend in treatment is organ-preserving surgery. To avoid regrowth of cancer, this type of surgery can be combined with radiation therapy. Since external radiation includes healthy tissue surrounding the cancerous zone, a local and direct intraoral radiation delivery would be beneficial.MethodsA general concept for a trans-oral radiation system was designed, based on clinical need identification with a medical user. A miniaturized X-ray tube was used as the radiation source for the intraoperative radiation delivery. To reduce dose distribution on healthy areas, the X-ray source was collimated by a newly designed adjustable shielding system as part of the housing. For direct optical visualization of the radiation zone, a miniature flexible endoscope was integrated into the system. The endoscopic light cone and the field of view were aligned with the zone of the collimated radiation. The intraoperative radiation system was mounted on a semi-automatic medical holder that was combined with a frontal actuator for rotational and translational movement using piezoelectric motors to provide precise placement.ResultsThe entire technical set-up was tested in a simulated environment. The shielding of the X-ray source was verified by performing conventional detector-based dose measurements. The delivered dose was estimated by an ionization chamber. The adjustment of the radiation zone was performed by a manual controlling mechanism integrated into the hand piece of the device. An endoscopic fibre was also added to offer visualization and illumination of the radiation zone. The combination of the radiation system with the semi-automatic holder and actuator offered precise and stable positioning of the device in range of micrometres and will allow for future combination with a radiation planning system.ConclusionsThe presented system was designed for radiation therapy of the oral cavity and the larynx. This first set-up tried to cover all clinical aspects that are necessary for a later use in surgery. The miniaturized X-ray tube offers the size and the power for intraoperative radiation therapy. The adjustable shielding system in combination with the holder and actuator provides a precise placement. The visualization of radiation zone allows a targeting and observation of the radiation zone.

Transoral endoscopic thyroidectomy—essentiality of classification

Since the adoption of natural orifice translumenal endoscopic surgery (NOTES) for thyroid surgery via transoral access, its popularity has increased worldwide, especially in Asian countries. The advantage of this innovative surgery is its scar-free result, which is ideal for all kinds of operations. However, care must be taken to classify the transoral endoscopic thyroidectomy approach appropriately because they are completely different in technique and outcome.

Toward Transoral Peripheral Lung Access: Combining Continuum Robots and Steerable Needles.

Lung cancer is the most deadly form of cancer in part because of the challenges associated with accessing nodules for diagnosis and therapy. Transoral access is preferred to percutaneous access since it has a lower risk of lung collapse, yet many sites are currently unreachable transorally due to limitations with current bronchoscopic instruments. Toward this end, we present a new robotic system for image-guided trans-bronchoscopic lung access. The system uses a bronchoscope to navigate in the airway and bronchial tubes to a site near the desired target, a concentric tube robot to move through the bronchial wall and aim at the target, and a bevel-tip steerable needle with magnetic tracking to maneuver through lung tissue to the target under closed-loop control. In this work, we illustrate the workflow of our system and show accurate targeting in phantom experiments. Ex vivo porcine lung experiments show that our steerable needle can be tuned to achieve appreciable curvature in lung tissue. Lastly, we present targeting results with our system using two scenarios based on patient cases. In these experiments, phantoms were created from patient-specific computed tomography information and our system was used to target the locations of suspicious nodules, illustrating the ability of our system to reach sites that are traditionally inaccessible transorally.

Application of a computer-assisted flexible endoscope system for transoral surgery of the hypopharynx and upper esophagus.

Zenker's diverticulum is a common pathology in the transition zone of the posterior hypopharynx and esophagus. Surgical treatment is routinely performed by ENT and general surgeons. Besides the traditional open transcervical diverticulectomy, the introduction of transoral rigid treatment led to a paradigm change and is now the preferred treatment option for patients who are fit for general anesthesia. The implementation of interventional flexible endoscopy has opened another new micro-invasive approach for patients with high morbidity. Here, we present the potential utilization of a flexible, single port, robot-assisted, and physician-controlled endoscope system to facilitate transoral surgical access to the hypopharynx and upper esophagus. Transoral surgery of the hypopharynx and upper esophagus was performed in human cadavers (n = 5) using the Flex System (Medrobotics, Raynham, USA). Anatomical landmarks were identified, and posterior cricothyroid myotomy was performed with compatible flexible instruments in all cases. The approach to the hypopharynx and upper esophagus using the Flex system is feasible in a cadaveric model. Myotomy with a flexible tool and needle knife (from the perspective of treatment of Zenker´s diverticulum) was successful in all cases. Visualization of the surgical site with the system's HD camera is suitable and the flexible instruments meet the special needs of a micro-invasive transoral approach. Zenker´s diverticulum can be potentially treated with a transoral minimally invasive approach using a computer-assisted flexible endoscope system. This setup could be of advantage in patients with reduced mobility of the cervical spine to prevent open transcervical surgery. In our study, the Flex system enabled advanced visualization of the surgical site and extended intervention options, compared to standard flexible endoscopic treatment. However, general anesthesia is mandatory for the presented approach. Application in live patients with actual pathologies of the hypopharynx and upper esophagus will have to prove suitability for the treatment of Zenker's diverticulum. Further development of the system could include improved instrumentation and an adoption by other disciplines with challenging anatomy such as colorectal surgery.

The Hybrid Transoral-Pharyngotomy Approach to Oropharyngeal Carcinoma: Technique and Outcome.

The indications, techniques, and outcomes for a minimally invasive surgical approach in oropharyngeal squamous cell carcinoma (OPSCC) unsuitable for transoral resection are not well-described. A retrospective case series was performed using a prospectively assembled database of transoral surgery-treated OPSCC patients who also underwent a "hybrid" approach of combined transoral and limited pharyngotomy for tumor resection. Disease and functional outcomes were evaluated. Twenty patients underwent complete tumor resection using the hybrid approach. Median follow-up was 48 months. No postoperative pharyngocutaneous fistula occurred. One patient (5%) had a local recurrence. Kaplan-Meier estimates for disease-specific survival at 2 and 5 years were 94.4% (95% CI, 84%-100%) and 87% (95% CI, 70%-100%). All but 1 patient (due to chemoradiotherapy-related chondroradionecrosis) were decannulated, and 2 required long-term gastrostomy. In the absence of a favorable transoral access, the "hybrid" approach of combined transoral and limited pharyngotomy can accomplish margin-negative primary tumor resection, with a high degree of disease control and functional recovery in selected OPSCC patients.

Transoral thyroidectomy—from experiment to clinical implementation

As worldwide first group who initiated the transoral access to the thyroid we report on our personal experience and conceptual design in dealing with this innovative approach that was part of our Natural Orifice Surgery (NOS/NOTES) project which is the next step in the evolution of minimally invasive surgery. The transoral thyroidectomy is a safe method that represents a breakthrough for the patient and a paradigm shift in the history of thyroid surgery toward a scarless and hopefully also pain-free surgery.

Transoral thyroidectomy—from experiment to clinical implementation

: As worldwide first group who initiated the transoral access to the thyroid we report on our personal experience and conceptual design in dealing with this innovative approach that was part of our Natural Orifice Surgery (NOS/NOTES) project which is the next step in the evolution of minimally invasive surgery. The transoral thyroidectomy is a safe method that represents a breakthrough for the patient and a paradigm shift in the history of thyroid surgery toward a scarless and hopefully also pain-free surgery.

Endoscopic thyroidectomy: the transoral approach.

Transoral endoscopic thyroid surgery seems to be the logical consequence in the evolution of thyroid surgery. Animal and cadaver studies have shown that different endoscopic techniques can be performed in a safe and successful way. Presently, the minimally invasive aspect and cosmetic advantage seem to be the most important factor for the patients. However, even if these procedures are feasible in patients, the transoral access must still be considered as experimental. In this study then we aim at comparing the available literature on transoral thyroid surgery with our own experience in this field. The access itself needs to be further refined, and even more suitable and better adapted instruments need to be developed so that optimal and safe results that meet all requirements on endocrine surgery can be achieved and all requirements for endocrine surgery are met. The transoral thyroidectomy should only be performed in highly specialized centres for endocrine and endoscopic surgery. As an alternative, a combination with endoscopic non-transoral techniques-so called hybrid techniques-might be useful for our patients.

Hybrid procedure for total laryngectomy with a flexible robot-assisted surgical system.

Total laryngectomy is a standard procedure in head-and-neck surgery for the treatment of cancer patients. Recent clinical experiences have indicated a clinical benefit for patients undergoing transoral robot-assisted total laryngectomy (TORS-TL) with commercially available systems. Here, a new hybrid procedure for total laryngectomy is presented. TORS-TL was performed in human cadavers (n = 3) using a transoral-transcervical hybrid procedure. The transoral approach was performed with a robotic flexible robot-assisted surgical system (Flex®) and compatible flexible instruments. Transoral access and visualization of anatomical landmarks were studied in detail. Total laryngectomy is feasible with a combined transoral-transcervical approach using the flexible robot-assisted surgical system. Transoral visualization of all anatomical structures is sufficient. The flexible design of the robot is advantageous for transoral surgery of the laryngeal structures. Transoral robot assisted surgery has the potential to reduce morbidity, hospital time and fistula rates in a selected group of patients. Initial clinical studies and further development of supplemental tools are in progress. Copyright © 2016 John Wiley & Sons, Ltd.

Transoral Robotic Cleft Palate Surgery

Objective This study aimed to assess the safety and feasibility of transoral robotic surgery for the reconstruction of soft palatal clefts. Design The application of transoral robotic surgery for soft palate muscle reconstruction was investigated. The da Vinci Surgical Robot was first used on a cadaver to assess the optimal positioning of the patient and the robot. The robot was then used for the dissection and reconstruction of palatal muscles in 10 consecutive patients with palatal clefts. The procedures were documented using video and still photography. A group of 30 control patients were subjected to surgery with manual instruments. Surgical and clinical outcomes were evaluated with at least 6 months of follow-up (8 ± 1 months). Results The use of the surgical robot on a cadaver provided great dexterity and excellent 3D depth perception. The transoral access was efficient and safe for the precise dissection, reorientation, and suturing of palatal muscles. In our series, the surgical duration was longer for the robotic approach than for the manual approach (87 ± 6 minutes versus 122 ± 8 minutes, P < .0001). No intraoperative or postoperative complications occurred in either group. A robotic surgical approach can be used safely for palatal surgery. We believe that the precise dissection of the palatal muscles provided by the robotic system might reduce damage to the vascularization and innervation of these muscles, as well as damage to the mucosal surfaces that could cause fistula formation. In addition, this technique might improve palatal function and Eustachian tube function in cleft palate patients.

The versatility of spandex photographic retractor for transoral surgical procedures

The trend toward transoral access, be it for pathology or facial cosmetic surgery, has become increasingly popular over the last two decades with facial incisions being used more and more sporadically than otherwise. Transoral access because of its inherent limitations, retraction of the oral and perioral tissues without inducing physical or thermal injury makes it a daunting task for the operating surgeon. The use of conventional retractors in conjunction with surgical instruments can lead to inadvertent injury to the perioral tissues resulting in untoward postoperative sequelae leading to patient discomfort and delayed recovery. This article elucidates the versatility of a simple photographic retractor (spandex) as a useful adjunctive tool in the retraction and protection of the perioral tissues for almost all transoral surgical procedures.

Trans-oral robotic cleft surgery (TORCS) for palate and posterior pharyngeal wall reconstruction: A feasibility study

Robot-assisted surgery has become increasingly routine, replacing open and laparoscopic techniques in certain domains, with recent extension to head and neck surgery through trans-oral access. Some advantages of the robot-assisted surgery include the ability to access confined spaces, enhanced dexterity instrumentation with intuitive movement, motion scaling, tremor elimination and three-dimensional (3D) endoscopic viewing with true depth perception. The aim of this study was to investigate the technical feasibility of trans-oral robotic cleft surgery (TORCS) to access the posterior pharyngeal wall and palate for potential use in the cleft population. All possible permutations of patient and robotic instrument configurations were used with the daVinci Si Surgical System® (Intuitive Surgical, USA) 0° and 30° 3D endoscopes and 8-mm training instruments to determine the optimal visualization and surgical access to the palate and posterior pharynx in a paediatric airway manikin, and to simulate posterior pharyngeal wall surgery. A full robot-assisted cadaveric Hynes pharyngoplasty was performed using 5-mm training instruments. Experiments were recorded with still and video photography. TORCS is technically feasible in the paediatric cleft population. We predict a short learning curve due to the intuitive instrumentation, easier dissection and the potential to limit secondary insult compared with traditional surgery, as well as improved ergonomics for the operating surgeon. The as-yet unreported use of robotic-assisted cleft palate surgery may considerably enhance a surgeon's ability to perform difficult procedures of the palate and posterior pharynx in selected patients with limited access as well as lay the foundation for potential novel techniques.

A Bronchial Puncture Mechanism for Transoral Access to the Lung Parenchyma1

A Bronchial Puncture Mechanism for Transoral Access to the Lung Parenchyma1

Demonstration of nasopharyngeal surgery with a single port operator-controlled flexible endoscope system.

Nasopharyngeal surgery is commonly performed with a rigid endoscope using a transnasal or transoral approach. Here, we demonstrate a flexible single port computer-assisted endoscopic system enabling easy transoral access to the nasopharynx. Transoral nasopharyngeal surgery was performed in human cadavers (n = 8) using the Flex System (Medrobotics, Raynham, MA). Learning curves were evaluated based on the time necessary for reaching the Eustachian tube. Mock surgical procedures were performed with compatible flexible instruments. Nasopharyngeal surgery is feasible with the Flex System with a nontraumatic approach. The inbuilt HD digital camera enables high-quality visualization of the nasopharynx. The design of the flexible compatible tools adequately meets the requirements for surgical procedures in the nasopharynx. The single port operator-controlled flexible endoscope system is a feasible way to approach the nasopharynx for surgical manipulation. Further clinical studies as well as development of supplemental tools are in progress.