PubMed Health⌕ Search

Biomedical subjects

Lillian Wong

Publications and source records attributed to Lillian Wong.

3 recordsLinked to original sources

Effect of adhesion on the acoustic functioning of partial ossicular replacement prostheses in the cadaveric human ear.

BACKGROUND: Adhesion formation following ossiculoplasty surgery has been implicated as a cause of the progressive deterioration of an initially good postoperative hearing result. Scar tissue between the partial ossicular reconstruction prosthesis (PORP) and adjacent middle ear structures is a common finding at revision surgery. OBJECTIVES: This study aims to investigate the effects of simulated scarring on the microacoustic transmission characteristics of a PORP in the fresh cadaveric human temporal bone. METHODS: Cortical mastoidectomy and extended posterior tympanotomy permitted access to reflective markers placed on the stapes footplate. A sound stimulus at 80 to 95 dB was presented to the closed external ear canal and displacements were measured with the laser Doppler vibrometer. PORPs were placed in cadaveric specimens, and the shaft of the prosthesis was cemented to the adjacent promontory using dental cement. Serial measurements were made from the stapes footplate as the adhesive was allowed to harden, a process that we have taken to simulate the gradual fixation of the prosthesis by scarring in the live patient. RESULTS: There was a consistent reduction in stapes footplate displacement as the cement hardened. CONCLUSION: The gradual adhesion of a PORP to the promontory produces a consistent reduction in microacoustic transfer to the stapes footplate in the fresh human cadaveric model.

Acoustics↗

Electrosurgical adenoid ablation.

OBJECTIVE: The technique of adenoidectomy has undergone many refinements over the years with, most recently, the addition of electrosurgery alone as a viable method for removal of adenoid tissue. Several studies have suggested good efficacy with this method. The objective of this study is to examine the effectiveness of adenoidectomy by electrosurgical ablation by the following measures: reduction of the adenoid size, blood loss, and postoperative complications. DESIGN AND METHODS: In this prospective study, we reviewed patients who underwent electrosurgical adenoid ablation for either nasal obstructive symptoms or chronic otitis media with effusion requiring a second or greater set of pressure equalization tubes and adenoidectomy. Preoperative and postoperative videonasopharyngoscopy were performed and evaluated. A grading system for adenoid size for the endoscopic parameters was used. The amount of blood loss and postoperative complications were recorded. RESULTS: On preoperative nasopharyngoscopy, 7 of 23 children had a grade II adenoid size, 15 of 23 had grade III adenoid pads, and 1 of 23 had grade IV adenoid size. Postoperative follow-up at 6 to 8 weeks revealed that 19 of 23 children showed no evidence of adenoid tissue. Three of 23 children had only tiny residual tissue that fell into grade I and one had regrowth of tissue to fit into grade III. Eight patients were seen at 6 months postoperatively, four of whom were followed up to 12 months postoperatively; all showed no evidence of regrowth of adenoid tissue. Average blood loss for the procedure was 2.6 cc. No postoperative complications (postoperative bleed, dehydration requiring hospitalization, infection, velopharyngeal insufficiency) were encountered. CONCLUSIONS: Electrosurgical adenoid ablation is a safe method with minimal intraoperative blood loss and postoperative complications. Follow-up at 6 to 8 weeks and up to 1 year postoperatively suggests that it is an effective method in removing adenoid tissue and alleviating nasal obstruction.

Adenoidectomy↗