Bert W. O’Malley

Robotic Microlaryngeal Surgery: A Technical Feasibility Study Using the daVinci Surgical Robot and an Airway Mannequin

Objectives/Hypothesis: The trend toward minimally invasive surgery has led to the development and mastery of endoscopic and laparoscopic surgical techniques. These minimally invasive approaches, which only two decades ago were either novel or experimental, are now mainstream. More recently, robot‐assisted surgery has evolved as an adjunct to open and endoscopic techniques. Surgical robots are now approved by the United States Food and Drug Administration for a variety of thoracic and abdominal/pelvic surgical procedures. The purpose of this study is to demonstrate the technical feasibility of robot‐assisted microlaryngeal surgery.

Transoral Robotic Surgery Alone for Oropharyngeal Cancer: An Analysis of Local Control

OBJECTIVE To evaluate local control following transoral robotic surgery (TORS) with the da Vinci Surgical System (Intuitive Surgical Inc) as a single treatment modality for oropharyngeal squamous cell carcinoma (OSCC). DESIGN Prospective, single-center, observational study. SETTING Academic university health system and tertiary referral center. PATIENTS Thirty adults with previously untreated OSCC. INTERVENTION Transoral robotic surgery with staged neck dissection as indicated. MAIN OUTCOME MEASURES Local control and margin status. RESULTS Thirty patients were enrolled with previously untreated OSCC and no prior head and neck radiation therapy. Follow-up duration was at least 18 months. At the time of diagnosis, 9 tumors were T1 (30%); 16 were T2 (53%); 4 were T3 (13%); and 1 was T4a (3%). The anatomic sites of these primary tumors were tonsil in 14 (47%), tongue base in 9 (30%), glossotonsillar sulcus in 3 (10%), soft palate in 3 (10%), and oropharyngeal wall in 1 (3%). There was only 1 patient (3%) who had a positive margin after primary resection; further resection achieved a final negative margin. Perineural invasion was noted in 3 tumors (10%). No patient received postoperative adjuvant therapy. At a mean follow-up of 2.7 years (range, 1.5-5.1 years), there was 1 patient with local failure (3%). CONCLUSION As the only modality used for treatment of pathologically low-risk OSCCs, TORS provides high local control and is associated with low surgical morbidity.

An algorithmic approach to the diagnosis and management of invasive fungal rhinosinusitis in the immunocompromised patient

Acute invasive fungal rhinosinusitis is a difficult disorder to diagnose and treat. A systematic approach to the susceptible patient, however, leads to an earlier diagnosis with improved survival. Early evaluation with rigid nasal endoscopy with frozen section biopsy of suspicious lesions or the middle turbinate should be considered in the high-risk population. Complete surgical resection and the reversal of neutropenia appear to be critical elements in achieving a successful outcome in patients with invasive fungal rhinosinusitis.

Transoral Robotic Surgery of the Skull Base: A Cadaver and Feasibility Study

Objective: The goal of this study was to determine the potential role as well as the current limitations of the da Vinci Surgical System robot in transoral surgery of the skull base. Methods: The da Vinci robot was used to perform dissections of the skull base on 7 cadaver heads with their neck and clavicles intact. Neurosurgeons and otolaryngologists familiar with all facets of the open microscopic, minimally invasive, endoscopic and transoral robotic surgical procedure proceeded with the approach to and dissection of the human skull base. Results: The da Vinci robot provided superb illumination and 3-dimensional depth perception. The 30- degree endoscope improved cephalad visualization, and the ‘intuitive’ nature of the da Vinci surgical robot arms provided an advantage by their ability to suture the dura at the level of the clivus. An entirely transoral route provides access to the middle and lower clivus as well as the infratemporal fossa, but access to the sellar region and anterior cranial fossa is limited via a purely transoral route. Tremor-free dural closure was successfully performed. Conclusion: Our findings suggest that transoral robotic surgery utilizing the da Vinci robot system holds great potential for skull base surgical resection of extradural and intradural tumors of the middle and lower clivus and infratemporal fossa. A collaborative approach with neurosurgeon and otolaryngologist alternating at the master console and bedside is a successful strategy. Further instrument development is necessary, and continued investigation is warranted.

Understanding contraindications for transoral robotic surgery (TORS) for oropharyngeal cancer

Transoral robotic surgery (TORS) was invented at the University of Pennsylvania in 2004 and arose from a specifically designed translational research program which included airway mannequin, cadaver, and animal model experimentation. The success of these preclinical efforts led to the first prospective human clinical research trial of TORS in 2005 [1, 2]. In 2009 the outcomes report from a multi-institutional retrospective trial, led by Weinstein and O’Malley [3] at the University of Pennsylvania, was utilized by the United States Food and Drug Administration (FDA) to approve the use of the da Vinci Surgical System (Intuitive Surgical Inc, Sunnyvale, CA, USA) for TORS in patients. TORS procedures have been described to manage pathologies at numerous anatomic sites from the glottis and hypopharynx to the nasopharynx and skull base [4–6]. The most commonly reported use of TORS for malignant disease, however, has been for oropharyngeal cancer, particularly tongue base or tonsillar cancer [3, 7, 8]. This paper presents the contraindications for TORS oropharyngeal cancer resection as developed and performed at the University of Pennsylvania. One of the unique aspects of the adoption of TORS has been that the inventors of the techniques have remained the primary post-graduate teachers of the procedure worldwide. Two of the authors of this paper (GSW and BWO) developed a structured TORS training program and a Robotics Training Lab at the University of Pennsylvania at which over 300 surgeons have been trained to date. A major focus of the dissemination of TORS and of the training program has been the emphasis on the indications and contraindications of this new category of surgical procedures. Our goal in developing TORS contraindications has been to (1) minimize the vascular complications encountered during and after the procedures (2) ensure successful and reproducible functional outcomes and (3) to maximize the achievement of negative margins thus avoiding the additional morbidity of high intensity adjuvant therapy. The following is a categorized list of these contraindications: Vascular contraindications to TORS for oropharyngeal cancer

Endoscopic Resection of Advanced Anterior Skull Base Lesions: Oncologically Safe?

Aims: (1) Learn if margins of resection in advanced anterior skull base tumors that are resected via endoscopic-assisted means are comparable with traditional craniofacial resection (CFR). (2) Understand the difference in patient morbidity with endoscopic surgery compared to traditional CFR. Methods: Retrospective review of 41 patients undergoing surgery for comparably staged advanced malignancies of the anterior skull base between 2000 and 2006. Eighteen patients underwent endoscopic surgery and 23 patients underwent traditional CFR for American Joint Committee on Cancer stage III, IV or Kadish stage C lesions of the paranasal sinuses and anterior skull base. Margins were evaluated and follow-up ranged from 3 months to 5 years. Results: Of the 18 patients undergoing endoscopic resections, margins were positive/close in 17% (3/18). Margins were positive/close in 17% (4/23) of patients undergoing CFR. Five complications were seen in 4/18 patients (22%) undergoing endoscopic surgery and 11 postoperative complications were seen in 7/23 patients (30%) undergoing CFR. Mean duration of hospitalization was 5.22 and 7.17 days for the endoscopic and CFR groups, respectively. Conclusions: There does not appear to be increased risk of positive margins in patients with advanced lesions undergoing endoscopic-assisted resection. Furthermore, the incidence of morbidity and duration of stay may be improved with endoscopic techniques.

The chemopreventive and clinically used agent curcumin sensitizes HPV- but not HPV+ HNSCC to ionizing radiation, in vitro and in a mouse orthotopic model

Radiation therapy (RT) plays a critical role in the local-regional control of head and neck squamous cell carcinoma (HNSCC). However, the efficacy of RT in treating HNSCC is limited by severe normal tissue toxicity, predominantly mucositis. One pharmacological approach for increasing the clinical response to RT is the use of radiation response modifiers that preferentially sensitize tumor cells. Previously we demonstrated that curcumin, a natural plant polyphenol, increased the radiation sensitivity of HNSCC cells and that the observed sensitization was dependent on curcumin-mediated inhibition of thioredoxin reductase 1 (TxnRd1) a key cytosolic regulator of redox-dependent signaling. Here, we examined curcumin-induced radiation sensitization in HNSCC cell lines with differing HPV status and expressing different levels of TxnRd1, in vitro. The intrinsic radiation resistance of the HPV- cell lines was significantly higher than the HPV+ cell lines used in our study. Notably, all of the HPV- cell lines expressed high levels of TxnRd1 and exhibited higher intrinsic resistance to RT. While curcumin was effective at increasing the radiation response of the resistant HPV- cell lines it had no effect on the HPV+ cells. Based on these findings we employed an orthotopic, HPV- HNSCC tumor model in athymic nude mice to examine the effect of combining curcumin with fractionated RT, in vivo. The combination of curcumin feeding and fractionated RT had a significant effect on tumor doubling time and overall animal survival. We therefore propose that curcumin and RT should be considered as a first line treatment of HPV- HNSCC.

Anesthetic Considerations for Transoral Robotic Surgery

During the past decade, robotic surgery has been progressively incorporated into the mainstream of cardio-thoracic and abdominopelvic surgery. With the recent US Food and Drug Administration approval of transoral robotic surgery (TORS) for the treatment of all benign tumors and select malignant tumors of the head and neck, robotic surgery has established its place in otolaryngologic surgery. Given the multispecialty applications and widespread use of robotic surgery, there exists a need for anesthesiologists to familiarize themselves with robotic surgery. This article focuses on TORS and the goal of which is to provide the anesthesiologist with a foundation for caring for the TORS patient in the perioperative period.

A novel chitosan-hydrogel-based nanoparticle delivery system for local inner ear application.

Hypothesis A chitosan-hydrogel-based nanoparticle (nanohydrogel) delivery system can be used to deliver therapeutic biomaterials across the round window membrane (RWM) into the inner ear in a mouse model. Background Delivering therapies to the inner ear has always been a challenge for the otolaryngologist. Advances in biomedical nanotechnology, increased understanding of the RWM diffusion properties, and discovery of novel therapeutic targets and agents, have all sparked interest in the controlled local delivery of drugs and biomaterials to the inner ear using nanoparticles (NPs). Methods Fluorescently-labeled liposomal NPs were constructed and loaded into a chitosan-based hydrogel to form a nanohydrogel, and in vitro studies were performed to evaluate its properties and release kinetics. Furthermore, the nanohydrogel was applied to the RWM of mice, and perilymph and morphologic analysis were performed to assess the NP delivery and distribution within the inner ear. Results NPs with an average diameter of 160 nm were obtained. In vitro experiments showed that liposomal NPs can persist under physiologic conditions for at least two weeks without significant degradation and that the nanohydrogel can carry and release these NPs in a controlled and sustained manner. In vivo findings demonstrated that the nanohydrogel can deliver intact nanoparticles into the perilymphatic system and reach cellular structures in the scala media of the inner ear of our mouse model. Conclusion Our study suggests that the nanohydrogel system has great potential to deliver therapeutics in a controlled and sustained manner from the middle ear to the inner ear without altering inner ear structures.

Transoral Robotic Surgery in Head and Neck Cancer: What Radiologists Need to Know about the Cutting Edge

The evolution of oncologic surgical technology has moved toward reducing patient morbidity and mortality without compromising oncologic resection or oncologic outcomes. The goals in treating head and neck cancer are to cure patients, as well as to provide quality of life by improving functional and social outcomes through organ-preservation therapies, which may include surgery, chemotherapy, and/or radiation therapy. Transoral robotic surgery (TORS) is an emerging technique that provides several benefits over existing treatment regimens and over open surgery for head and neck cancer, including reductions in operative times, blood loss, intensive care unit stays, and overall duration of patient hospitalization. Transoral robotic techniques allow wide-view, high-resolution, magnified three-dimensional optics for visualization of the mucosal surfaces of the head and neck through an endoscope, while avoiding the extensive external cervical incisions often required for open surgeries. Radiologists play an important role in the successful outcome of these procedures, both before and after TORS. Determining a cancer patients surgical candidacy for TORS requires a thorough preoperative radiologic evaluation, coupled with clinical and intraoperative assessment. Radiologists must pay particular attention to important anatomic landmarks that are clinical blind spots for surgeons. Knowledge of the expected postoperative imaging appearances, so that they can be distinguished from recurrent disease and second primary tumors, is essential for all radiologists involved in the care of these patients.