Effect of Chitodex gel in ear drum repair (tympanoplasty) surgery

The general purpose of this study is to compare Chitosan-dextran (Chitodex) gel versus current standard of care, Gelfoam, as a middle ear (ME) and external auditory canal (EAC) packing agent as part of tympanoplasty and mastoidectomy procedures to close tympanic membrane perforations (TMP). We aim to compare the success rates of tympanoplasty/mastoidectomy surgery between the two products and to identify the ME packing agent-of-choice to ensure TMP closure as well as minimal inflammation of the middle ear mucosa. The most critical measure of success during tympanoplasty and mastoidectomy surgery is the closure of a chronic, pre-existing TMP. As such, our primary outcome will be a measure of tympanic membrane closure. This is performed under direct vision during routine post-operative surveillance via the use of either a hand-held otoscope or an operating otologic microscope. We will aim to perform this check at 4 distinct time-points: 2 and 6 weeks post-op, 3 months post-op and 6 months post-op. Chitosan-dextran gel is packaged within a syringe and has a cannula attached, much like the Gelfoam syringe system. Approx 3-5mL of product is applied during the surgery. Approx 2mL into the middle ear, as a support material for the graft. After graft suturing is complete, another 3mL (approx) is applied into the external ear canal as a packing agent. This is the same procedure as Gelfoam is currently used for this purpose. The surgeon will administer the gel during the surgery as they would with the standard of care Gelfoam. The product comes in a sterile kit to be opened by Scrub Nurse. Fidelity of the interventions is measured in several ways by the surgeon at the end of the operation. A good seal for the graft is always assessed for by the surgeon prior to completing any tympanoplasty. This is determined via any evidence of air escape from the middle ear when palpating the tympanic membrane and graft at the end of the procedure. A good seal indicates a well-positioned graft. The surgeon’s operative notes will indicate this. We will also obtain endoscopic images and videos at the end of procedure to assess positioning of the graft.