Lee M. Akst

Risk factors for hypopharyngeal/upper esophageal stricture formation after concurrent chemoradiation

Concurrent chemoradiation therapy has been demonstrated to be effective as an organ‐sparing treatment for select advanced head and neck squamous cell carcinoma (HNSCC). However, this treatment modality is not without side effects. One side effect is the formation of upper esophageal strictures. As concurrent chemoradiation treatment is used more frequently, it is important to identify risk factors associated with stricture formation.

Long‐term Effects of Micronized Alloderm Injection for Unilateral Vocal Fold Paralysis

Objectives: Micronized Alloderm (Cymetra) is a relatively new product used for vocal fold augmentation. Previous studies evaluating possible long‐term effectiveness of this product have shown mixed results. The objective of this present study is to reassess possible long‐term results of Cymetra injection laryngoplasty in patients with unilateral true vocal fold paralysis.

Results of ansa to recurrent laryngeal nerve reinnervation

Objective We sought to describe the results of ansa cervicalis to recurrent laryngeal nerve (ansa-RLN) reinnervation for unilateral vocal fold paralysis. Study Design A chart review was performed on patients undergoing ansa-RLN reinnervation for unilateral vocal cord paralysis at a tertiary care center. Patient perceptions of preoperative and postoperative voice quality was surveyed. Acoustic and visual parameters were assessed from videostroboscopy. Results From a total of 25 study patients, 15 patients underwent both preoperative and postoperativ video stroboscopies. In stroboscopies within 6 months, the average improvement in overall severity, roughness, and breathiness was 69, 79, and 100 percent, respectively. In stroboscopies after 6 months, the average improvement in overall severity, roughness, and breathiness was 63, 66, and 100 percent, respectively. Postoperatively, all patients had reinnervation of the vocal fold. Conclusions Voice outcomes were improved in patients with preoperative and postoperative stroboscopies. Significance Ansa-RLN reinnervation should be considered as a treatment for unilateral vocal fold paralysis.

Office-based and microlaryngeal applications of a fiber-based thulium laser.

Objectives: The carbon dioxide (CO2) laser is the premier dissecting instrument for hemostatic cutting and ablation during endolaryngeal surgery. However, microlaryngeal tangential dissection and office-based photoablation have been limited by the lack of a fiber-based delivery system. To address this limitation, a new laser was designed, which is a diode-pumped solid-state laser with a thulium-doped yttrium-aluminum-garnet laser rod. It produces a continuous-wave beam with a wavelength of 2,013 nm and a target chromophore of water. This new laser functions similarly to a CO2 laser with the benefit of being delivered through a small glass fiber (0.365 to 0.550 mm). Methods: A prospective pilot trial was done in 74 cases to explore applications of the new thulium laser. Thirty-two procedures were done with the laser used as an ablating instrument and topical anesthesia through a flexible laryngoscope (papillomatosis, 20; microinvasive carcinoma, 6; benign supraglottic lesions, 3; edema, 2; granuloma, 1). Forty-two procedures were done with the laser used as a cutting or ablating instrument for microlaryngeal dissection and general anesthesia. These included 27 partial laryngeal resections (supraglottis, 15; glottis, 10; subglottis, 2) and 8 posterior glottic laryngoplasties. The laser was also used as an ablative instrument during microlaryngoscopy in 7 cases. Results: The thulium laser was used effectively in all cases, under both local and general anesthesia. In microlaryngeal dissection, electrocautery was not needed to control bleeding, even during cutting in the highly vascular paraglottic space. No complications related to the use of the thulium laser were experienced in any case. Conclusions: Because of the fiber-based delivery system, the 2,013-nm continuous-wave thulium laser shows substantial promise for tangential dissection during microlaryngoscopy and soft tissue photoablation during office-based flexible laryngoscopy. Hemostasis was judged to be superior to experiences with the CO2 laser. In this pilot study, performing en bloc laryngeal cancer resection procedures was facilitated by use of the thulium laser.

532 nm pulsed potassium-titanyl-phosphate laser treatment of laryngeal papillomatosis under general anesthesia.

Objectives: Angiolytic lasers have been shown to be an effective treatment strategy for laryngeal papillomatosis. These lasers precisely target hemoglobin within the microcirculation of papillary lesions. We have previously demonstrated the advantages of the fiber‐based pulsed 532‐nm potassium‐titanyl‐phosphate (KTP) laser in an office setting (with local anesthesia). This investigation provides the first report of the pulsed‐KTP laser during microlaryngoscopy under general anesthesia.

Functional outcomes following chemoradiotherapy for head and neck cancer

OBJECTIVE: To study functional outcomes following concurrent chemoradiotherapy of head and neck cancer. METHODS: A retrospective chart review assessed diet, feeding tube use, and tracheotomy pretreatment and 3, 6, 12, and 24 months posttreatment. RESULTS: Of 196 patients who underwent chemoradiotherapy between 1990 and 2002, 148 (76%) required feeding tubes immediately posttreatment; 150 (77%) required nutritional support at 3 months. By 12 months, 92% were tube-free and 83% resumed near-normal diet. Of 17 patients (9%) with tracheotomy posttreatment, 71% were decannulated by 6 months. Stage IV disease strongly predicted prolonged feeding tube use and slow recovery of diet; age ≥60 also predicted slow recovery. Primary site, gender, and radiotherapy schedule did not predict functional recovery after adjusting for stage and age. CONCLUSION: Few patients required tracheotomy before or during chemoradiotherapy. Many patients required feeding tubes and nutritional support for several months following therapy, but most were tube-free and eating near-normal diets within 1 year. EBM rating: C.

Effects of 532 nm pulsed-KTP laser parameters on vessel ablation in the avian chorioallantoic membrane: Implications for vocal fold mucosa

Objectives: Selective vascular ablation (photoangiolysis) using pulsed lasers that target hemoglobin is an effective treatment strategy for many vocal fold lesions. However, vessel rupture with extravasation of blood reduces selectivity for vessels, which is frequently observed with the 0.45‐ms, 585‐nm pulsed dye laser. Previous studies have shown that vessel rupture is the result of vaporization of blood, an event that varies with laser pulse width and pulse fluence (energy per unit area). Clinical observations using a 532‐nm wavelength pulsed potassium‐titanyl‐phosphate (KTP) laser revealed less laser‐induced hemorrhage than the pulsed dye laser. This study investigated settings for the pulsed KTP laser to achieve selective vessel destruction without rupture using the avian chorioallantoic membrane under conditions similar to flexible laryngoscopic delivery of the laser in clinical practice.

Induction of tolerance in a rat model of laryngeal transplantation

Background. The major limitation preventing expansion of laryngeal transplantation as a therapeutic modality is the necessity of lifelong immunosuppression. In this report, we describe an immunomodulatory strategy for tolerance induction in laryngeal allotransplantation that permits escape from chronic immunosuppression. Materials and Methods. Larynges were transplanted from Lewis-Brown-Norway (RT1l/n, F1) donors to Lewis (RT1l) recipients. Recipients received 7 days of treatment with tacrolimus and mouse anti-rat &agr;&bgr; T–cell-receptor (TCR) monoclonal antibodies. Histology, mixed lymphocyte reaction (MLR), skin grafting, and flow cytometry assessed functional tolerance, efficacy of immunodepletion, and donor-specific chimerism. Results. All 10 recipients survived until sacrifice at 100 days. Histology suggested functional allograft tolerance. Skin grafting, MLR, and flow cytometry revealed that tolerance is neither donor-specific nor related to systemic immunocompromise. Conclusions. In this rat laryngeal-transplantation model, functional tolerance was induced under combined tacrolimus and &agr;&bgr; TCR protocol. Mechanisms responsible for this tolerance induction require future elucidation.

Comparison of a Flexible Laryngoscope with Calibrated Sizing Function to Intraoperative Measurements

Objectives: The objectives were to assess the clinical performance and accuracy of a prototype fiberoptic transnasal laryngeal endoscope with an auxiliary optical system that allows images to be spatially calibrated. Methods: A novel fiberoptic endoscope was developed that projects green laser beams across the field of view from a separate optical channel. According to the location of the spots in the field of view, the images can be calibrated with a software routine. To assess its performance, we compared measurements of 14 lesions imaged with the calibrated endoscope and during microlaryngoscopy, where a calibration instrument was placed next to the lesions. Four clinicians measured lesion length, width, and area from the collected images. Results: The calibrated endoscope performed as well as current flexible fiberoptic laryngoscopes in terms of image quality and patient comfort. For lesions with well-defined borders, the error ranged from 14% to 23% for length, from 20% to 30% for width, and from 33% to 50% for area across observers. Factors contributing to larger errors in some subjects were identified. Conclusions: The calibrated endoscope is capable of providing useful sizing information for laryngeal structures, and these measures correspond quite well to more direct measurements in the operating room. Objective sizing of laryngeal lesions is complicated by subjective judgments of lesion boundaries, which can be indistinct in many cases.

Risk Factors for Dysplasia in Recurrent Respiratory Papillomatosis in an Adult and Pediatric Population

Aim: Recurrent respiratory papillomatosis (RRP) is classically described as a benign neoplasm of the larynx caused by the low-risk human papillomavirus (HPV) viral subtypes. Nevertheless, transformation to dysplasia and invasive carcinoma can occur. We aimed to assess the prevalence of dysplasia and carcinoma-ex-papilloma in both adult-onset and juvenile-onset RRP and identify patient risk factors for this dysplastic transformation. Material and Methods: Ten-year retrospective chart review of a tertiary otolaryngology referral center. Patients with papilloma were identified from a review of a pathology database and clinical records. Patient demographics, pathologic data, and treatment history, including use of cidofovir as an adjunctive therapy for papilloma, were extracted from electronic medical records. Results: One hundred fifty-nine RRP patients were identified, 96 adult-onset (AORRP) and 63 juvenile-onset (JORRP) cases. Of this cohort, 139 (87%) had only benign papilloma as a pathologic diagnosis. In the AORRP cohort, 10 patients (10%) were diagnosed with dysplasia or carcinoma in situ in addition to papilloma, and 5 patients (5%) had malignant transformation to invasive carcinoma-ex-papilloma. There was a significantly higher age of disease onset for those with dysplasia or carcinoma versus those without dysplasia or carcinoma (56 vs 45 years old; P = .0005). Of the 63 JORRP patients, there were no cases of dysplasia but 3 (5%) cases of invasive carcinoma-ex-papilloma, all involving pulmonary disease. The JORRP patients with carcinoma-ex-papilloma had a younger average disease onset (2 vs 6 years old; P = .009) and a higher rate of tracheal involvement than those without carcinoma. Gender, smoking history, number of operations, or use of cidofovir showed no association with the development of dysplasia or carcinoma-ex-papillomatosis in either the AORRP or JORRP population. Conclusion: In a large series of RRP, age of disease onset is the strongest predictor of dysplastic transformation in the adult and pediatric population. Carcinoma-ex-papillomatosis was uniformly associated with pulmonary disease in the JORRP population in this series. No other demographic or behavioral factors, including adjunctive therapy with cidofovir, were statistically associated with dysplasia or carcinoma-ex-papilloma.