Sinus implants for chronic rhinosinusitis: technology evaluation

Footsteps of the Innovations in Rhinology

Rhinology is the study of nose, paranasal sinus, and nasopharynx. The nose is the most prominent structure on the human face and has been a subject of study since ancient human civilization. The history of rhinology has reflected the sociocultural aspects of the times, and rhinology has achieved remarkable growth with innovative discoveries by numerous pioneers. The focus of surgical procedures of the paranasal sinus shifted from mucosal stripping to functional endoscopic surgery with advancement of technology. Furthermore, the field of rhinology is gradually expanding due to cutting-edge technologies such as image-guided surgery, three-dimensional endoscopy, and robotic surgery. Additional clinical experiences and technological developments are expected to further advance rhinology.

Current Perspective on Nasal Delivery Systems for Chronic Rhinosinusitis

Chronic rhinosinusitis is an upper respiratory disease during which topical drug treatment via the nasal cavity is the most actively utilized therapeutic strategy. In addition to steroids, antibiotics, and antifungal agents, which are widely used in clinical practice, research on novel topical agents to improve the bacterial biofilm or mucociliary clearance remains ongoing. Moreover, owing to the complex structure of the nasal cavity, the effects of nasal drug delivery vary depending on factors related to delivery fluid dynamics, including device, volume, and compounds. In this article, we review methods and compounds that have been applied to chronic rhinosinusitis management and introduce recent advances and future perspectives in nasal drug delivery for upper respiratory diseases.

Local drug delivery systems for inflammatory diseases: Status quo, challenges, and opportunities

Inflammation that is not resolved in due course becomes a chronic disease. The treatment of chronic inflammatory diseases involves a long-term use of anti-inflammatory drugs such as corticosteroids and nonsteroidal anti-inflammatory drugs, often accompanied by dose-dependent side effects. Local drug delivery systems have been widely explored to reduce their off-target side effects and the medication frequency, with several products making to the market or in development over the years. However, numerous challenges remain, and drug delivery technology is underutilized in some applications. This review showcases local drug delivery systems in different inflammatory diseases, including the targets well-known to drug delivery scientists (e.g., joints, eyes, and teeth) and other applications with untapped opportunities (e.g., sinus, bladder, and colon). In each section, we start with a brief description of the disease and commonly used therapy, introduce local drug delivery systems currently on the market or in the development stage, focusing on polymeric systems, and discuss the remaining challenges and opportunities in future product development.

Evaluation of a steroid releasing sinus implant for the treatment of patients undergoing frontal sinus surgery for chronic rhinosinusitis

INTRODUCTION

Management of the frontal sinus places great demands on the otolaryngologist. Given that the fronto-ethmoidal region is susceptible to recurrent inflammation, scarring, and stenosis, maintaining long-term patency of the frontal sinus is a difficult challenge. Oral and topical anti-inflammatory therapy, post-operative stenting, and 'home-brew' drug elution have been used for the treatment of the frontal sinus with mixed success. Recently an implant has been approved for post-operative placement into the frontal recess. This implant provides reliable and consistent steroid drug elution to address inflammation of the frontal recess secondary to chronic sinusitis. Areas covered: This review discusses the development and application of steroid eluting implants in the postoperative care of patients with chronic frontal sinusitis. All randomized controlled trials evaluating steroid eluting implants are discussed. Relevant supporting material discussing background, economics, safety are included. Expert commentary: Steroid eluting implants fulfill a unique niche in the treatment following frontal sinus surgery. They are shown to decrease the need for post-operative interventions and improve outcomes in patients with chronic sinusitis. There is significant potential for growth in the use of steroid eluting implants.

In-office use of a steroid-eluting implant for maintenance of frontal ostial patency after revision sinus surgery

Achieving long-term, successful outcomes with endoscopic sinus surgery (ESS) can be challenging in patients with recalcitrant chronic rhinosinusitis (CRS). Local complications, including scar formation and ostial stenosis, can lead to recurrent blockage and subsequent relapse. The frontal sinus is particularly vulnerable to surgical failure given its narrow outflow and inaccessibility to topical therapies. The advent of steroid-eluting sinus implants has enhanced ESS outcomes, with significant reductions in synechiae, inflammation, and secondary postoperative interventions when placed in the ethmoid cavity. However, use of this technology in the frontal sinus has yet to be described. The purpose of this report is to present two cases, in which in-office frontal placement of a mometasone furoate (MF)-eluting implant facilitated maintenance of ostial patency after revision ESS. The clinical presentation, in-office intervention, and treatment outcomes were examined. Two patients (male, 63 and 68 years of age) with a history of multiple ESS presented with recurrent unilateral frontal headache refractory to medical therapy. Nasal endoscopy/imaging revealed frontal sinus outflow obstruction. Both declined revision ESS under general anesthesia and underwent endoscopic frontal sinustomy/ostial dilation in the clinic. A MF-eluting implant was placed in the frontal sinus at the end of the procedure, with preservation of ostial patency upon last follow-up at 3 and 11 months, respectively. In-office placement of a MF-eluting implant successfully maintained frontal ostial patency in patients with a history of multiple ESS. Additional randomized trials are necessary to determine statistical significance, cost-effectiveness analysis, and long-term efficacy of frontal sinus implantation.