ABSTRACT
OBJECTIVE: Unilateral vocal fold paralysis (UVFP) presents as incomplete glottal closure and leads to breathy hoarseness. Various treatments, including laryngeal framework surgery (type 1 thyroplasty [TP1] and arytenoid adduction [AA]), have been devised to correct this condition. Ultrahigh-resolution computed tomography (U-HRCT) allows detailed three-dimensional imaging of the larynx, which aids our understanding of vocal fold motion disorders. This study assessed whether U-HRCT is beneficial for correct diagnosis and surgical planning. METHODS: The participants were 26 UVFP patients who underwent laryngeal framework surgery (TP1 and/or AA). U-HRCT was used to measure the vocal fold volume (VFV) and level difference (LD). The need to combine AA with TP1 to obtain satisfactory surgical outcomes was evaluated by U-HRCT and various voice function tests. RESULTS: VFV was smaller in paralyzed folds than in unaffected folds. LD correlated strongly with voice parameters and showed high intra-rater and inter-rater reliability. The surgical outcome of the laryngeal framework surgery performed was judged to be excellent for improving voice function. Comparison of LD between the TP1 group and TP1 + AA group indicated that LD is an excellent parameter to determine the need to combine AA with TP1. CONCLUSION: These findings underscore the value of preoperative U-HRCT, especially LD, in surgical decision-making and afford insights for optimal phonosurgery and individualized intervention. Patients with LD >1.0 mm may benefit from thyroplasty with AA. LEVEL OF EVIDENCE: Level 3 (case-control study) Laryngoscope, 2024.
ABSTRACT
BACKGROUND: Ultra-high-resolution computed tomography (U-HRCT) utilizes a 1024 × 1024 matrix with 0.25-mm section thickness, offering better spatial resolution than conventional multi-detector row CT to detect anatomic data for otologic surgery. AIMS: We examined stapes footplate thickness using U-HRCT in relation to stapedotomy to predict the difficulty of the surgical procedure. MATERIALS AND METHODS: Subjects were 12 otosclerosis patients and 25 controls who underwent diagnostic U-HRCT. A profile curve (Hounsfield units) was used to measure stapes footplate thickness along a perpendicular line across the stapes footplate in a plane parallel to the lateral semicircular canal. RESULTS: Footplate thickness was smaller at the midpoint than just before the anterior crus and just after the posterior crus. Interobserver variability was lowest at the midpoint, where foot plate thickness was significantly greater in the affected ear in otosclerosis patients compared with controls (0.60 ± 0.09 mm vs 0.46 ± 0.04 mm; p < .001). Otosclerosis patients were detected using U-HRCT with a high area under the curve. Difficulty in the stapes opening procedure correlated with stapes footplate thickness. CONCLUSIONS: Footplate thickness on U-HRCT correlated with temporal bone anatomy and corresponded to surgical difficulty. Significance: U-HRCT-derived anatomic data is useful for evaluating the stapes.
