Endoscopic Exposure Research Articles

The endoscopic stapler diverticulotomy for Zenker's diverticulum.

This paper describes the surgical procedure of the endoscopic stapler treatment of Zenker's diverticulum and analyzes the results of 24 consecutive operated patients. In three patients the endoscopic exposure of the diverticulum was not possible. Twenty-one patients underwent endoscopic stapler treatment without any peri- or postoperative complications. The follow-up period was 4 to 29 months (average 18 months). The average total time for surgery was 25 min. Postoperatively, a nasogastric feeding tube was not necessary: all patients resumed oral intake 12 h after surgery. Discharge from the hospital followed the 2nd postoperative day. All patients had complete or nearly complete resolution of symptoms at the 4-month follow-up. Recurrent complaints were an indication for repeat of the contrast barium esophagram. Two patients revealed a residual diverticulum 7 and 11 months after treatment. In comparison with results and complication rates in the literature of the external, transcutaneous techniques and endoscopic diverticulotomy procedures, the endoscopic stapler treatment of Zenker's diverticulum is a safe, (cost-)effective and minimally invasive method and to be considered as the initial treatment of choice.

Endoscopic treatment of Zenker's diverticulum using CO2 laser.

The objective of the present study was to review the technique of endoscopic laser-assisted esophagodiverticulostomy (ELAED) for the treatment of Zenker's diverticulum. We reviewed 83 cases of ELAED performed for the treatment of Zenker's diverticuli during the past decade. ELAED-treated patients had a reduced hospital stay and were able to start an oral diet earlier than were patients who underwent other surgical procedures. Two (2.4%) of our patients developed small fistulas, which closed spontaneously. An additional 2 (2.4%) of our patients required conversion to an open approach due to inadequate endoscopic exposure, and 5 (6%) required a revision endoscopic procedure for persistent symptoms. Our series of 83 patients treated at 2 large academic centers during the past decade with an average follow-up of 4 years demonstrates that ELAED is a safe and effective procedure for the management of Zenker's diverticulum.

Endoscopically assisted Le Fort I osteotomy to correct transverse and sagittal discrepancies of the maxilla

Purpose: The purpose of this report was to show the feasibility of the combination of a minimally invasive endoscopic approach to the maxilla with transverse and sagittal distraction procedures. Materials and Methods: Four human cadavers were used for training of a minimally invasive access to the maxilla to perform a endoscopically assisted Le Fort I osteotomy, before this technique was applied in 3 patients with transverse and sagittal growth deficits of the maxilla. Access to the maxilla was gained through a small mucosa incision in the vestibule to create a visualization port to the maxillary sinus through a bur hole. Landmarks were identified through the endoscope before a Le Fort I osteotomy was performed using chisels of different shapes and angulations. In 2 patients the maxilla was split sagittally to perform a transverse maxillary expansion; in 1 patient, a buried distractor was applied close to the piriform aperture to correct a sagittal growth deficit in a hypoplastic maxilla. Results: Endoscopic exposure of the maxillary sinus walls from within the sinus, the accurate identification of landmarks, and the creation of a Le Fort I osteotomy were achieved in all cases. Distractor application close to the piriform aperture rendered good stability. Conclusion: The results of these cases indicate that the endoscopic approach to the maxillary sinus allows excellent exposure of the sinus walls to perform a endscopically assisted Le Fort I osteotomy. The combination of endoscopy and osteodistraction processes supports the tendency to perform minimally invasive, less-traumatizing surgical procedures, especially in individuals who are still growing. © 2002 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 60:1142-1145, 2002

Endoscopic approach to the ramus/condyle unit: Clinical applications

Purpose: The purpose of this report is to describe use of an endoscopic technique for exposure of the mandibular ramus/condyle unit (RCU) to facilitate reconstructive jaw procedures. Patients and Methods: This is a retrospective evaluation of 10 patients with diagnoses of idiopathic condylar resorption (n = 2), subcondylar fracture (n = 5), mandibular prognathism (n = 1), condylar hyperplasia (n = 1), and mandibular asymmetry (n = 1), who underwent endoscopic exposure of the RCU. Results: All 10 patients had successful reconstruction of the RCU using the endoscopic approach. The procedures performed included the following: condylectomy (n = 5 sides), costochondral graft reconstruction (n = 4 sides), reduction of subcondylar fracture (n = 5 sides), and mandibular ramus osteotomy (n = 4 sides). Mean operating time was 84 minutes. No patients had marginal mandibular nerve weakness or other complications. Conclusion: This case series demonstrates the feasibility of endoscopic access to the RCU. The procedures can be performed with no increase in operative time and with minimal morbidity. © 2001 American Association of Oral and Maxillofacial Surgeons

Minimally invasive orthognathic surgery: endoscopic vertical ramus osteotomy

The endoscopic procedure for placement and activation of a distraction device for mandibular advancement has been previously reported 20. The purpose of this study was to demonstrate the feasibility of endoscopic exposure, dissection and osteotomy for mandibular set-back. Two cadaver and three anesthetized minipigs were used in this study. Access to the mandibular ramus was achieved through a 2.0 cm submandibular incision. The dissection was carried sharply to the mandible and completed in the subperiosteal plane. Visualization was achieved using a 2.7 mm diameter endoscope (Karl Storz, Germany). Landmarks were identified and a custom-made retractor was inserted into the sigmoid notch. A vertical ramus osteotomy was created (bilaterally) from the sigmoid notch to the mandibular angle. The mandible was set back (average 6 mm) and fixed using 2.0 mm diameter, bicortical screws. Live animals were sacrificed three weeks postoperatively. The mandibles were examined clinically and radiographically to verify proper osteotomy position and clinical union. In all animals, exposure, accurate identification of landmarks, osteotomy placement and screw fixation were achieved. In the live animals ( n = 3), union between the proximal and distal segments was documented by clinical and radiographic examination. This study demonstrates the feasibility of the EVRO procedure for mandibular set-back in a minipig model.

Minimally invasive orthognathic surgery: endoscopic vertical ramus osteotomy

The endoscopic procedure for placement and activation of a distraction device for mandibular advancement has been previously reported20. The purpose of this study was to demonstrate the feasibility of endoscopic exposure, dissection and osteotomy for mandibular set-back. Two cadaver and three anesthetized minipigs were used in this study. Access to the mandibular ramus was achieved through a 2.0 cm submandibular incision. The dissection was carried sharply to the mandible and completed in the subperiosteal plane. Visualization was achieved using a 2.7 mm diameter endoscope (Karl Storz, Germany). Landmarks were identified and a custom-made retractor was inserted into the sigmoid notch. A vertical ramus osteotomy was created (bilaterally) from the sigmoid notch to the mandibular angle. The mandible was set back (average 6 mm) and fixed using 2.0 mm diameter, bicortical screws. Live animals were sacrificed three weeks postoperatively. The mandibles were examined clinically and radiographically to verify proper osteotomy position and clinical union. In all animals, exposure, accurate identification of landmarks, osteotomy placement and screw fixation were achieved. In the live animals (n=3), union between the proximal and distal segments was documented by clinical and radiographic examination. This study demonstrates the feasibility of the EVRO procedure for mandibular set-back in a minipig model.

Endoscopic mandibular osteotomy, and placement and activation of a semiburied distractor

Purpose: The purpose of this study was to demonstrate the feasibility of endoscopic placement and activation of a semiburied distraction device in the porcine mandible. Materials and Methods: Sixteen cadaver and two live anesthetized minipigs were used in this study. Access to the mandible was gained through two 1.0-cm submandibular incisions used for a working port and a visualization port. Under endoscopic visualization, dissection was carried sharply to the mandible and completed in the subperiosteal plane. Landmarks were identified through the endoscope, and a mandibular angle osteotomy was created. A semiburied distractor was then implanted, fixed to the mandible, and activated to create a bone gap. Finally, the site was explored through a submandibular incision to verify the accuracy of the endoscopic procedure. Results: Endoscopic exposure; accurate identification of landmarks; creation of an osteotomy; and placement, fixation, and activation of a semiburied distractor were achieved in all 18 specimens. The inferior alveolar nerve was identified as the bone gap was expanded. Conclusion: The results of this study indicate that the endoscopic approach described here allows exposure and osteotomy of the mandible, and placement, fixation, and activation of a distractor. In the future, this technique will be used with totally buried, miniature distraction devices.

Endoscopic Skull Base Surgery I: A New Animal Model for Pituitary Surgery

Endoscopy has emerged as a new means to perform minimally invasive surgery of the skull base. Specifically, endoscopic techniques and instruments can be used to safely and effectively approach and resect tumors of the pituitary gland in humans. No animal model currently exists to serve as a template upon which to refine and develop endoscopic surgical technique in this region of the anatomy. We operated on two purpose-bred Hampshire-Yorkshire-Duroc hybrid swine to demonstrate the application of endoscopy to pituitary surgery. Based upon similar anatomical relationships in humans and swine between the oropharynx, nasopharynx, and skull base, we used a transoral, transpalatal approach to access the vomer of the swine. Under endoscopic exposure, we resected the vomer, entered the sphenoid sinus, and then resected the sphenoid septum, sella turcica, and adenohypophysis. Clear visualization of the pituitary, hypophyseal stalk, cavernous sinuses, and carotid prominences was achieved and documented with digital photography. Benefits and limitations of the technique were noted. These results have pertinent implications both for the study of the surgical anatomy of the swine craniofacial skeleton, and for future development of endoscopic surgical manipulation of the skull base.

Experimental development of an endoscopic approach to neck exploration and parathyroidectomy

Background . Recent advances in minimally invasive surgical technology have the potential to lead to new applications outside body cavities. The purpose of the present study was to develop techniques for obtaining endoscopic exposure and access to the pretracheal space in the neck with the goal of performing neck exploration and parathyroidectomy and to evaluate the safety and efficacy of such an approach experimentally. Methods . The technique for endoscopic neck exploration was developed in eight adult mongrel dogs and was further evaluated in a survival dog model and in human cadavers. The pretracheal space was accessed by a 2.5 cm midline incision in the lower neck. This space was expanded with a balloon dissector, and exposure was maintained with an external lift device. A 5 or 10 12 mm midline port and two to four lateral 5 mm cervical ports were placed, and dissection was carried out with pediatric endoscopic instruments and an ultrasonic coagulator. Excised parathyroid tissue was verified histologically. Results . Two-gland parathyroidectomy was successfully completed in five of six dogs; inadequate exposure led to a failed procedure in one animal. Mean operative time was 130 ± 6 minutes, and there were no operative complications. Serum calcium levels did not change significantly after operation (p = not significant). At autopsy, approximately 20 ml of clear sterile fluid was present in the pretracheal space of every dog. In five human cadavers mean dissection time for attempted four-gland parathyroidectomy was 69 ± 38 minutes (range, 45 to 135 minutes). Four of four parathyroids were identified and removed in two patients, three of three parathyroids in one patient, three of four parathyroids in one patient, and two of four parathyroids in one patient. Conclusions . Parathyroidectomy may be performed safely and reliably in an animal model with minimally invasive techniques that can be applied to parathyroid dissection in human cadavers. These results suggest that an endoscopic approach to neck exploration and parathyroidectomy is potentially feasible and may warrant further study in clinical trials.

Microanatomical basis for the third ventriculostomy.

In the last few years, there has been a resurgence of interest in endoscopic third ventriculostomy as a treatment for obstructive hydrocephalus. Although various techniques have been used to perform this procedure, not enough emphasis has been placed on the microanatomical details of the third ventricle and surrounding cisterns in relation to this procedure. Using a surgical microscope we examined the microsurgical anatomy of the floor of the third ventricle floor and related subarachnoid cisterns in 20 adult brains using the "immersion technique" in conjunction with microsurgical dissection. We believe that the optimal place to fenestrate is the midline of the floor of the third ventricle, behind the infundibular recess and in front of the mammillary bodies, communicating the third ventricle with the anterior interpeduncular cistern, minimizing the risk for vascular lesions. Stereotactic third ventriculostomy is a safe and effective way of re-establishing normal cerebrospinal fluid flow dynamics in selected cases of obstructive hydrocephalus. However, in an endoscopic exposure only a small portion of the anatomy can be seen at any one time, and important neurovascular structures may be located adjacent to the endoscope, but outside of the visual range of the lens. A thorough understanding of the microanatomy of the neural and vascular structures surrounding the third ventricle and related cisterns is essential in order to improve surgical results avoiding complications.

Endoscopic Surgery for Frontal Sinusitis and Its Complications

Endoscopic surgery of the paranasal sinuses has become popular during recent years, but the endonasal approach into the frontal sinus was only rarely recommended. Using a surgical endoscope with 70° optical deflection, the fenestration of the frontal sinus from below has proved a valuable and safe procedure in more than 500 procedures. The control of complications like osteitis and mucopyoceles, and of foreign bodies and benign tumors has become practical with endoscopic exposure.

Percutaneous transtracheal ventilation for laser endoscopic treatment of laryngeal and subglottic lesions.

Obstructive lesions of the larynx and subglottic space are always a challenging problem for the endoscopist and anaesthetist. At this level, the efficacy and innocuity of a carbon dioxide laser treatment are related to the degree of endoscopic exposure. Thanks to the transtracheal high frequency jet ventilator, it is now possible to assure a free laryngeal endoscopic operative field. The transtracheal catheter is introduced percutaneously through the cricothyroid membrane into the trachea under endoscopic control and connected to a high frequency jet ventilator. From November 1983 to April 1985, this technique has been used in 65 cases. In 12 cases, it was the only alternative to avoid a tracheostomy. The other indications were: laryngeal papillomatosis, resection of T1a cancers of the vocal cords, fibrous strictures secondary to long term intubation, laser arytenoidectomies and benign lesions of the vocal cords. Among many advantages, the following are the most convincing: clear vision of the operative field for the surgeon, complete relaxation of the patient, good respiratory gas exchange, elimination of the risk of ignition of an endotracheal tube by laser, decreased risks of broncho-aspiration of blood and debris, and the facility to provide oxygen and/or mechanical ventilation in the postoperative period. The only complication encountered was a case of cervico-mediastinal emphysema caused by displacement of the tracheal catheter.