Cost-effectiveness Analysis of Submandibular Gland Preservation With Sialendoscopy for the Management of Sialolithiasis.

OBJECTIVE: To compare the cost-effectiveness of sialendoscopy with gland excision for the management of submandibular gland sialolithiasis. STUDY DESIGN: Cost-effectiveness analysis. SETTING: Outpatient surgery centers. METHODS: A Markov decision model compared the cost-effectiveness of sialendoscopy versus gland excision for managing submandibular gland sialolithiasis. Surgical outcome probabilities were found in the primary literature. The quality of life of patients was represented by health utilities, and costs were estimated from a third-party payer's perspective. The effectiveness of each intervention was measured in quality-adjusted life-years (QALYs). The incremental costs and effectiveness of each intervention were compared, and a willingness-to-pay ratio of $150,000 per QALY was considered cost-effective. One-way, multivariate, and probabilistic sensitivity analyses were performed to challenge model conclusions. RESULTS: Over 10 years, sialendoscopy yielded 9.00 QALYs at an average cost of $8306, while gland excision produced 8.94 QALYs at an average cost of $6103. The ICER for sialendoscopy was $36,717 per QALY gained, making sialendoscopy cost-effective by our best estimates. The model was sensitive to the probability of success and the cost of sialendoscopy. Sialendoscopy must meet a probability-of-success threshold of 0.61 (61%) and cost ≤$11,996 to remain cost-effective. A Monte Carlo simulation revealed sialendoscopy to be cost-effective 60% of the time. CONCLUSION: Sialendoscopy appears to be a cost-effective management strategy for sialolithiasis of the submandibular gland when certain thresholds are maintained. Further studies elucidating the clinical factors that determine successful sialendoscopy may be aided by these thresholds as well as future comparisons of novel technology.

Does a "Fundal Fluid Cap" Predict Successful Hearing Preservation in Vestibular Schwannoma Resections Via the Middle Cranial Fossa Approach?

OBJECTIVE: To determine the association between radiographic cerebrospinal fluid (CSF) cap in the lateral internal auditory canal (IAC) and likelihood of successful hearing preservation in middle cranial fossa (MCF) vestibular schwannoma (VS) surgery. STUDY DESIGN: Retrospective chart review. SETTING: Academic tertiary referral center. PATIENTS: One hundred thirty-eight consecutive patients (mean age/standard deviation, SD, 50/11 yr) who underwent MCF VS resection. INTERVENTIONS: MCF VS excision. MAIN OUTCOME MEASURES: Size of fundal fluid cap on preoperative magnetic resonance imaging (MRI), pre- and postoperative pure-tone average (PTA), and word recognition score (WRS). RESULTS: Mean tumor and fundal fluid sizes were 9.7 mm (SD, 3.9 mm) and 2.8 mm (SD, 1.7 mm), respectively. On bivariate analysis, fundal fluid size was associated with larger tumor size (p = 0.005) but not changes in postoperative PTA (p = 0.45) or WRS (p = 0.17). When fundal fluid size was stratified as none (<1 mm), small (≥1 mm and <4 mm), and large (≥4 mm), no significant differences were seen in rates of hearing preservation. Using multivariate linear regression models adjusting for patient age, sex, tumor nerve of origin, neurofibromatosis type II status, and preoperative PTA and WRS, superior vestibular nerve tumor origin but not increasing fundal fluid size was associated with preserved postoperative PTA or WRS. CONCLUSIONS: Presence or size of CSF fluid cap may not be a reliable prognostic indicator for hearing preservation in MCF VS resection, with important implications for patient counseling.

How Well Does Intraoperative Audiologic Monitoring Predict Hearing Outcome During Middle Fossa Vestibular Schwannoma Resection?

OBJECTIVE: To evaluate the association between signal changes during intraoperative audiologic monitoring and postoperative audiometric outcome in patients undergoing vestibular schwannoma (VS) resection via middle cranial fossa (MCF) approach. STUDY DESIGN: Retrospective chart review. SETTING: Academic tertiary referral center. PATIENTS: One hundred twenty-six consecutive patients (mean age 48.6 yrs, range 16-67; mean tumor size 9.9 mm, range 1.8-18.9 mm) who underwent MCF VS resection. INTERVENTIONS: Intraoperative audiologic monitoring using auditory brainstem response (ABR) and direct cochlear nerve action potential (CNAP). MAIN OUTCOME MEASURES: Intraoperative ABR wave V and CNAP N1 amplitudes and postoperative pure-tone average (PTA) and word recognition score (WRS). RESULTS: On ABR, absent wave V amplitude was associated with an 81.1% increase and 82.3% decrease in postoperative PTA and WRS, respectively. On CNAP, decreased or absent N1 amplitude was associated with 47.3 and 100% increase, respectively, in postoperative PTA, and 45.3% and 100% decrease, respectively, in postoperative WRS. Receiver-operating curve analysis showed that ABR combined with CNAP using a Cueva electrode achieved the highest diagnostic accuracy in predicting postoperative hearing decline when measured by WRS class (sensitivity 83.3%, specificity 100%), and performed better compared with each modality alone. CONCLUSION: Intraoperative ABR wave V and CNAP amplitude changes are associated with changes in postoperative hearing, and dual modality monitoring was more diagnostic of postoperative hearing decline compared with each modality alone during MCF VS resection. Overall, intraoperative ABR and CNAP were more specific than sensitive for postoperative hearing decline.

Intraductal Laser Fiber Tip Fracture and Retrieval During Sialendoscopic Laser-Assisted Lithotripsy.

Fragmentation of flexible laser fiber tips has been reported to occur during therapeutic bronchoscopy and urologic stone treatment. We report fragmentation of 200-µm single-use silica-based fibers during sialendoscopy-controlled Holmium:YAG laser treatment of a parotid and a submandibular stone. The technique employed to successfully retrieve the fiber tips is described in the context of identifying this potential complication from endoscopic management of sialolithiasis.