A modified V-shaped incision combined with superficial musculo-aponeurotic system flap for parotidectomy.

BACKGROUND: V-shaped incision (VSI) for parotidectomy had been introduced for cosmetic purpose. Despite having aesthetic superiority, it required excessive retraction or an additional hairline incision for adequate surgical exposure. To overcome these problems, we conceptualized a modified VSI approach combined with a separate superficial musculo-aponeurotic system flap. AIMS: This study aimed to propose this approach and evaluate its technical feasibility and efficacy for excision of parotid tumors. MATERIALS AND METHODS: This is a prospective, nonrandomized study involving 74 patients with small-to-medium (<4 cm), benign parotid tumors located superficially. The patients were divided into two groups based on the incision techniques used: modified VSI and modified Blair incision (MBI). The clinical outcomes of both approaches for parotidectomy were analyzed. RESULTS: Thirty-four patients underwent modified VSI approach, while 40 underwent MBI. All parotidectomies with modified VSI were successfully completed without any further incision, and no facial nerve injury or intraoperative tumor rupture complication was reported. There were no significant differences in the complications between both approaches, such as hematoma, infection, wound dehiscence, skin necrosis, sialocele, or sensory disturbance. The modified VSI group showed better cosmetic satisfaction results than did the MBI group (9.2 and 7.8, respectively; p < .001). CONCLUSIONS AND SIGNIFICANCE: The modified VSI approach is safe and feasible for small-to-medium benign parotid tumors. This approach could be a possible option for patients with a high cosmetic demand. LEVEL OF EVIDENCE: 4. STUDY DESIGN: Prospective pilot study.

Real-Time Light-Guided Vocal Fold Injection: Ex Vivo Feasibility Study in a Canine Model.

OBJECTIVE: The transcricothyroid (CT) membrane approach is a good option for office-based vocal fold injection (VFI). However, because the needle tip is invisible during injection using the CT approach, precise localization requires a high level of experience, and mastering this approach involves a steep learning curve. To overcome current limitations, we conceptualized a novel technique: real-time light-guided VFI (RL-VFI), which enables simultaneous VFI under direct visualization of the lighted needle tip. Herein, we aimed to verify the feasibility of RL-VFI in cadaveric canine model, simulating the setting of office-based VFI, as well as to explore its clinical usefulness. STUDY DESIGN: Animal study. METHODS: A customized prototype device was developed. It consisted of three parts: light source, controller, and injector. Light source comprised laser diodes of two wavelengths (635 nanometers [nm], red; 532 nm, green). Four types of injector were developed using 40-mm needles of 23- and 25-gauge and optic fibers of 50 and 100 µm. ex vivo canine larynx was prepared for the experiment. Flexible laryngoscopy system was used to examine canine vocal folds. RESULTS: Various routes from three insertion points (3 mm, 10 mm, and 17 mm from the midline) were validated using the device. Regardless of the injection routes, the location of the needle tip was accurately indicated by light. RL-VFI was feasible under light guidance without difficulties. Moreover, precise and simultaneous re-injection could be performed at the intended point using the device. CONCLUSION: We introduced RL-VFI using our customized prototype device in an ex vivo canine larynx, simulating the setting of office-based VFI. Clinical application of RL-VFI will improve safety and precision of CT approach, as well as expand its applications in laryngology. LEVEL OF EVIDENCE: NA. Laryngoscope, 129:935-942, 2019.

Some posterior branches of extralaryngeal recurrent laryngeal nerves have motor fibers.

OBJECTIVES/HYPOTHESIS: Anatomical variations of the recurrent laryngeal nerve (RLN), such as extralaryngeal branching, are a well-known risk factor for RLN injury during thyroid surgery. This study aimed to analyze the surgical anatomy and to investigate the existence of posterior branch motor fibers of extralaryngeal RLNs. STUDY DESIGN: Prospective consecutive observational study. METHODS: This was a prospective cohort study of 366 patients between January 2014 and February 2016. Operative data included the type of operation, incidence of nerve bifurcation, the distances among anatomical landmarks. The motor fibers were evaluated using neurostimulation with laryngeal palpation. RESULTS: A total of 667 RLNs at risk were analyzed in this study, and of these 103 (14.5%) nerves were bifurcated or trifurcated before the laryngeal entry point (LEP). More extralaryngeal branched RLNs were observed on the right side than on the left (17.5% vs. 13.3%, P = .294). The mean distance of the LEP point of division was longer on the left side (16.2 ± 6.7 mm) than on the right (14.7 ± 5.9 mm, P = .132). All branched RLNs had a palpable laryngeal twitch when stimulating anterior branches. When stimulating posterior branches, 28.2%(29/103) of branched RLNs showed palpable laryngeal twitch. Overall incidence of posterior motor branch in total RLNs was 4.3% (29/667). CONCLUSIONS: The motor fibers of the RLN are all located in the anterior branch, whereas some posterior branches have motor function. Identification of all of the branches of the RLN may be mandatory to decrease the risk of postoperative nerve injury. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:2678-2685, 2017.

Liquid-type Botulinum Toxin Type A in Adductor Spasmodic Dysphonia: A Prospective Pilot Study.

OBJECTIVES: Botulinum toxin (BTX) has been widely used to treat adductor spasmodic dysphonia (ADSD). Most commercially available forms of BTX require reconstitution before use, which may increase the risk of contamination and requires careful titration. Recently, a liquid-type BTX type A (BTX-A) has been developed, which should simplify the procedure and enhance its efficacy. Herein, we present a prospective pilot study to investigate the efficacy and safety of liquid-type BTX-A in the treatment of ADSD. METHODS: Twenty-six consecutive liquid-type BTX-A injections were performed in 12 patients with ADSD. We included as a control group 34 consecutive patients with ADSD who had previously undergone 52 vocal fold injection procedures with freeze-dried-type BTX-A. RESULTS: All patients in both groups had improvement of symptoms related to ADSD and period of normal voice. Most patients experienced breathiness, and the onset time, the peak response time, and the duration of breathiness were similar in both groups. The duration of effect (days) was 96.96 ± 18.91 and 77.38 ± 18.97 in the freeze-dried-type and the liquid-type groups, and the duration of benefit (days) was 80.02 ± 18.24 and 62.69 ± 19.73 in the freeze-dried-type and the liquid-type groups. To compare the efficacy between the freeze-dried-type and the liquid-type BTX-A, the sessions of the unilateral vocal fold injection were included and were categorized as group A (1 ~ 2 units BTX-A) and group B (2 ~ 3 units BTX-A), according to the dose per vocal fold. There was no significant difference of effect time between freeze-dried-type and liquid-type BTX-A groups. No adverse events related to BTX or vocal fold injection were reported. CONCLUSIONS: Liquid-type BTX-A is safe and effective for the treatment of spasmodic dysphonia. With the advantages of simple preparation, storage, and reuse and animal protein-free constituents, liquid-type BTX-A may be a good option in the treatment of spasmodic dysphonia.