Flash pump dye laser treatment of laryngeal papillomas

Transoral flexible laser surgery of the upper aerodigestive tract with blue laser

PURPOSE

The introduction of fiber-guided lasers was a breakthrough in laryngology practice, opening the path for treating different pathologies with minimally invasive procedures, both in the operating room and in the office. The most recent technology in the area is the blue laser, which combines photoangiolytic and cutting properties, characteristics that make this equipment suitable for its use in upper aerodigestive tract surgery. However, there is not enough experience in this area. The authors present a case series of patients with different pharyngeal, laryngeal, and tracheal pathologies who were treated by means of transoral procedures using fiber-guided blue laser.

METHODS

The surgical records of patients with different upper aerodigestive tract pathologies who were treated with fiber-guided blue laser in the operating room, under general anesthesia with jet ventilation or supraglottic ventilation using suspension laryngotracheoscopy techniques between February 2018 and March 2022 were reviewed.

RESULTS

A total of 80 surgical interventions in a group of 38 patients were performed. A wide variety of procedures was executed, either using the laser alone or in combination with other techniques to treat different pathologies of the aero-digestive tract safely and effectively, with adequate functional results.

CONCLUSIONS

Following all necessary precautions, blue laser is a reliable tool to perform minimally invasive surgeries in the operating room using TOFLS techniques. It can be used alone or in combination with other devices to achieve the desired goals.

Histologic effect of the potassium-titanyl phosphorous laser on laryngeal papilloma

Objectives

Tissue effects occurring with potassium‐titanyl phosphorous (KTP) laser treatment are difficult to quantify due to the multiple variables that affect not only the fluence (energy delivered) but also the laser–tissue interaction. This histopathologic analysis of recurrent respiratory papilloma (RRP) removed after treatment with KTP laser therapy permits correlation of histologic effect with method of laser treatment.

Methods

The histopathology of RRP resected specimens in a single patient was compared following treatment with KTP laser in contact and non‐contact modes as documented with intraoperative photography and video imaging.

Results

Epithelial‐sparing injury selective to the microvasculature was identified on histopathologic assessment of a specimen treated with noncontact angiolysis. Highly cauterized papillomatous epithelium without identifiable vascular structures was identified on tissue removed after treatment with the KTP laser in contact mode.

Conclusion

The histopathologic assessment of acute KTP laser effect on papilloma permits correlation between technique of application and tissue effect. Similar assessments may be helpful to modify dosimetry for individual patients requiring repeated treatment and may also assist in refining the development of existing KTP laser treatment classification systems.

Level of Evidence

4

Pressure induced tissue resection in the larynx: A preliminary canine study

OBJECTIVES

The application of laser (light amplification by stimulated emission of radiation) energy in the larynx relies on thermal injury. The impact of this injury on adjacent tissue can be undesirable. Attempts have been made to limit the extent and range of injury to adjacent tissue. The O-Pel Surgical System (Precise Light Surgical, Inc., Campbell, CA), a new technology, utilizes kinetic energy through Pressure Induced Tissue Resection (PITR) (Precise Light Surgical, Inc.) to cut tissue, theoretically eliminating injury to adjacent tissue. The purpose of this study was to evaluate the PSL in canine vocal folds.

METHODS

Four dogs underwent PITR incisions (4 mJ pulses at 200 Hz) on their vocal folds, through mucosa into the muscle. The animals were sacrificed at days 0, 3, 7, and 21 days postsurgery. The larynges were harvested and histology was performed with hematoxylin and eosin, Masson trichrome, and Verhoeff-van Gieson.

RESULTS

At day 0, focal denudation of the epithelium and coagulation necrosis in the lamina propria and adjacent connective tissue are noted. On days 3 and 7, an inflammatory infiltrate of neutrophils is seen within the lamina propria and surrounding connective tissue with minimal edema and early deposition of collagen. At day 21, the mucosa is completely regenerated with the area of previous PITR into the muscle replaced with thick bundles of collagen.

CONCLUSION

The unique PITR characteristics offer a potentially unique cutting technology for laryngeal microsurgery. The current canine study suggests appropriate and rapid healing. With refinements of the tip size of the probe and adjustment of energy, PITR will likely be an appropriate alternate to traditional lasers in laryngeal surgery.

LEVEL OF EVIDENCE

NA. Laryngoscope, 129:2557-2562, 2019.

585-NM Pulsed Dye Laser Treatment of Glottal Dysplasia

Management of glottal dysplasia can be difficult and often results in a suboptimal treatment outcome. The surgeon and patient must cooperatively balance decisions regarding the effects of possible malignancy, vocal dysfunction, and recurrences leading to multiple use of general anesthetics. A pilot study was done in 57 cases (36 patients and 97 vocal folds) without complication to evaluate the effectiveness of a 585-nm pulsed dye laser (PDL; 450-μs pulse width, 19 to 76-J/cm2 fluence, 1- to 2-mm spot size) in the treatment of vocal fold keratosis. Forty of the 57 cases had bilateral treatment. Phonomicrosurgical resection was done in 35 of the 57 cases after PDL treatment. Of this group, 10 cases were found to have hyperplasia, 21 dysplasia, 4 carcinoma in situ, and 1 carcinoma. One patient had phonomicrosurgical resection before PDL treatment. In 21 of the 57 cases, the disease was irradiated without resection (4 unilateral lesions and 17 bilateral lesions). Approximately 80% of the patients in this series had a greater than 70% reduction in the size of the lesion with the use of the PDL irrespective of whether they underwent resection. Clinical observation revealed no new anterior commissure web formation despite bilateral anterior commissure treatment in 28 of the 57 cases. The PDL enhanced the epithelial excision by improving hemostasis and by creating an optimal dissection plane between the basement membrane and the underlying superficial lamina propria. In this initial trial, the PDL provided relatively safe and effective treatment for glottal dysplasia. Analysis of patterns of recurrence will require longer follow-up.

Office-Based Treatment of Glottal Dysplasia and Papillomatosis with the 585-NM Pulsed Dye Laser and Local Anesthesia

Treatment of glottal papillomatosis and dysplasia was mirror-guided and performed in surgeons' offices in the 19th century. It migrated to the operating room in the 20th century to accommodate direct laryngoscopic surgery, which required assistants to administer anesthesia and procedural support. Presently, the primary treatment goals, which are disease regression and voice restoration or maintenance, are tempered by the morbidity of general anesthesia and potential treatment-induced vocal deterioration. In fact, general anesthesia has been appropriately considered to be an acceptable source of morbidity for the promise of a precise procedure, which usually ensures airway safety and an optimal vocal outcome. However, patients with recurrent glottal papillomatosis and keratosis with dysplasia are typically monitored with various degrees of watchful waiting until there is a subjective judgment (on the part of the patient and surgeon) that the disease is more of a liability than is the procedure to treat it. Innovations in the 585-nm pulsed dye laser delivery system have allowed for its use in the clinic with local anesthesia through the working channel of a flexible fiberoptic laryngoscope. A prospective assessment was done on 51 patients in 82 cases of recurrent glottal papillomatosis (30) and dysplasia (52). All individuals had previously undergone microlaryngoscopic management with histopathologic evaluation. Five procedures could not be completed because of impaired exposure (2) or discomfort (3). Of those patients who could be treated, there was at least a 50% disease involution in 68 of 77 cases (88%) and 25% to 50% disease regression in the remaining 9 (12%). Patient self-assessment of the voice revealed that 34 of 77 were improved, 39 were unchanged, 4 were slightly worse, and none were substantially worse. These data confirm that diseased mucosa can be normalized without resection or substantial loss of vocal function. The putative mechanisms, which vary according to the fluence (energy) delivered by the laser, are photoangiolysis of sublesional microcirculation, denaturing of epithelial basement membrane linking proteins, and cellular destruction. Furthermore, this relatively safe, effective technique allowed for treatment of many patients (in a clinic setting) in whom classic surgery-related morbidity would have often delayed intervention.

In-Office Laryngeal Surgery with the 585nm Pulsed Dye Laser (PDL)

OBJECTIVES: The 585nm pulsed dye laser (PDL) is a promising tool for in-office laryngeal surgery. Data with respect to the safety and efficacy of the PDL for office laryngeal use is sparse. The purpose of this study is to review our experience with unsedated office PDL surgery.

METHODS: Records of individuals undergoing in-office PDL between September 1, 2004, and September 1, 2006 were abstracted from a clinical database.

RESULTS: Forty-seven patients underwent 117 treatments. The most common indications were recurrent respiratory papillomatosis (RRP), Reinke's edema, and vocal fold polyps. One hundred and four of 117 procedures were felt to be a success ablating all disease. Thirteen treatments requred early termination. The most common factor responsible for termination was an inability to achieve a comfortable level of anesthesia. One patient with Reinke's edema developed postprocedure stridor that required a 3-day hospital admission for observation and corticosteroids. There was no incidence of any vocal fold scarring, web formation, or other complications.

CONCLUSIONS: The 585nm PDL is a promising tool for in-office treatment of various laryngeal disorders. Complications are rare.

Safety and dosing of bevacizumab (avastin) for the treatment of recurrent respiratory papillomatosis

OBJECTIVES

Increasing evidence supports the use of laryngeal injections of the antiangiogenic agent bevacizumab (Avastin) for the adjuvant treatment of recurrent respiratory papillomatosis (RRP). A recent prospective open-label investigation, approved by the US Food and Drug Administration, employing 12.5 mg of sublesional bevacizumab demonstrated single-site efficacy without complications; however, the safety of multiple-site injections and higher dosing has not yet been reported. The primary objective of this study was to report on the safety of increased doses of bevacizumab for the treatment of RRP.

METHODS

Two cohorts of adult patients were evaluated. In the first group, a prospective analysis was performed on patients with a diagnosis of laryngeal RRP after t heir participation in th e initial clinical trial with a single-site lowerdose (7.5 to 12.5 mg). They received higher doses of sublesional laryngeal bevacizumab (15 to 50 mg total) with detailed physiologic, hematologic, and serum chemistry measurements performed before and after each bevacizumab injection. A second cohort of patients received sublesional laryngeal injections of bevacizumab (15 to 88 mg total) without physiologic measurements and underwent a retrospective analysis of reported complications.

RESULTS

One hundred consecutive laryngeal injection sessions (office, 87; operating room, 13) with bevacizumab were performed in 43 patients, with a mean dose of 30 mg total per treatment (range, 15 to 88 mg). Sixty-three of the 100 sessions were accompanied by KTP laser photoangiolysis of the papilloma prior to bevacizumab injections. Eighteen patients (cohort 1) underwent detailed physiologic assessment, and no dysfunction was observed. There were no local or systemic complications of bevacizumab administration. The second group of 25 patients (cohort 2) also reported no significant local or systemic complications. Neither patient group was observed to have a local wound problem in the larynx.

CONCLUSIONS

This investigation provides evidence that higher doses of bevacizumab are relatively safe in adult patients with laryngeal RRP. Further refinements in pharmacologic concentration and drug delivery will determine the optimal treatment regimens in the future.

[Papillomas & laryngeal papillomatosis. Treatment with CO₂ laser surgery. Our experience over 15 years]

OBJECTIVES

The study goal was to evaluate the efficacy of CO₂ laser surgery in the treatment of laryngeal papillomatosis. We analysed several parameters such as gender, average age, relapse rate and viral serotype.

MATERIAL AND METHODS

A total of 26 diagnosed patients were included in this retrospective descriptive review. All of them were treated with CO₂ laser for laryngeal papillomas between 1995 and 2010.

RESULTS

This pathology was more prevalent in males (65.5%), with a slight predominance of a single larynx localisation over multiple lesion locations. Human papillomavirus (HPV) DNA was detected in 75.8% of the cases; genotypes 6 and 11 prevailed. Of the patients in this review, 44.8% relapsed; the relapse average was 2-3 episodes per patient. A total of 20.7% of cases were in remission (no relapse in the last 2 months); 34.5%, clearing (no apparent relapse in the last 3 years); and 41.3% in the healing stage (without relapse in the last 5 years). There was only one case that showed malignancy.

CONCLUSION

Papillomatosis is characterised as a pathology with an unpredictable course and with a low probability of malignancy. CO₂ laser surgery has meant a revolution in symptomatic treatment, but there is presently no curative treatment.

Microlaryngoscopic and office-based injection of bevacizumab (Avastin) to enhance 532-nm pulsed KTP laser treatment of glottal papillomatosis

OBJECTIVES

Photoangiolytic lasers effectively treat glottal papillomatosis, but do not reliably prevent recurrence. Therefore, sublesional injections of the antiangiogenic agent bevacizumab (Avastin) were given to assess the effect on disease recurrence and phonatory function.

METHODS

A retrospective investigation was done in a pilot group of 10 adult patients with bilateral glottal papillomatosis who had prior angiolytic laser treatment with established patterns of recurrence. The patients underwent 5 bevacizumab injections (5 to 10 mg) into the diseased vocal folds along with 532-nm pulsed KTP laser photoangiolysis treatments 4 to 6 weeks apart. Their disease resolution was compared to findings from prior laser treatment alone, and objective measures of vocal function (acoustic, aerodynamic, Voice-Related Quality of Life survey) were obtained.

RESULTS

All 10 patients had a greater than 90% reduction in recurrence. Four of the 10 had resolution. Four of the 10 have limited recurrent or persistent disease, receive injections of bevacizumab at 8- to 12-week intervals, and have not required laser treatment. Two of the 10 have ongoing periodic office-based KTP laser treatment along with bevacizumab injections. No patient has required microlaryngeal surgery with general anesthesia, and all 10 have had substantial improvement in vocal function.

CONCLUSIONS

This pilot investigation provides preliminary evidence that bevacizumab injections enhance photoangiolytic laser treatment of glottal papillomatosis while enhancing phonatory function. Coupling an antiangiogenesis agent with pulsed KTP laser photoangiolysis is conceptually promising, since the mechanisms of action are complementary.

Value and utility of 532 nanometre pulsed potassium-titanyl-phosphate laser in endoscopic laryngeal surgery

Objectives:

Recently, the 532 nm pulsed potassium-titanyl-phosphate laser has emerged as an effective angiolytic laser for treating mucosal lesions of the larynx in the operating theatre and clinic. We sought to assess the current impact of potassium-titanyl-phosphate laser on our laryngeal surgery practice.

Study design:

Retrospective review of 710 patients undergoing endoscopic laryngeal surgery over a one-year period.

Methods:

Medical records of the endoscopic laryngeal procedures were reviewed; 386/710 had been performed in the clinic and 324/710 in the operating theatre under general anaesthesia. Indications for the procedures were classified by pathology.

Results:

Pulsed potassium-titanyl-phosphate laser was used in 209/386 clinic procedures. The indications for these procedures were: dysplasia (114/209 procedures), papillomatosis (89/209), varices or ectasia (three of 209), and ‘other’ (three of 209). Pulsed potassium-titanyl-phosphate laser was used in 178/324 operating theatre endoscopic laryngeal procedures. The indications for these procedures were: cancer (54/178 procedures), dysplasia (52/178), papillomatosis (38/178), varices or ectasia (13/178), polyps (six of 178), nodules (six of 178), stenosis (five of 178), granulation (three of 178), and amyloid (one of 178).

Conclusions:

Due to its versatility, the 532 nm pulsed potassium-titanyl-phosphate laser is our most commonly utilised instrument for performing endoscopic laryngeal surgery.

Use of lasers in laryngeal surgery

Lasers are a relatively recent addition to laryngeal surgery. Since their invention, laser use and applications have expanded rapidly. In this article, we discuss the benefits and disadvantages of lasers for different procedures, as well as ways to overcome commonly faced clinical problems. The use of lasers in surgery has offered a time- and cost-efficient alternative to cold surgical techniques, and has been used in the treatment of numerous laryngeal pathologies, including stenoses, recurrent respiratory papillomatosis, leukoplakia, nodules, malignant laryngeal disease, and polypoid degeneration (Reinke's edema). However, lasers can incur adjacent tissue damage and vocal fold scarring. These problems can be minimized through understanding the mechanisms by which lasers function and correctly manipulating the parameters under a surgeon's control. By varying fluence, power density, and pulsation, tissue damage can be decreased and lasers can be used with greater confidence. The various types of lasers and their applications to the treatment of specific pathologies are reviewed with the intention of helping surgeons select the best tool for a given procedure. Recent applications of lasers to treat benign laryngeal lesions and severe laryngomalacia demonstrate that additional research must be conducted to realize the full potential of this surgical tool.

[Laryngeal papillomatosis: etiology, diagnostics and therapy]

Papillomas are rare tumors that originate from the mucosa. They may appear in the nose, paranasal sinuses, oral cavity, larynx, trachea, or the skin. Papillomas are mainly asymptomatic and are therefore mostly diagnosed coincidentally. In contrast, laryngeal papillomatosis may cause stridor, dyspnoea, and hoarseness. A viral cause of the disease seems likely, especially human papilloma virus. Mechanical irritation is also a possible reason when the nose, oral cavity, or oropharynx is affected. All papillomas, independent of their origin, may recur, and have the possibility of malignant degeneration in common. The therapy of choice is complete surgical excision. Regarding laryngeal papillomatosis, laser vaporisation or excision using the CO(2)laser is recommended. Because retreatments using conventional modalities are frequently necessary, especially in the case of laryngeal papillomatosis, adjuvant therapies are applied with the aim of reducing the recurrence rate and prolonging the interval between treatments.

Recurrent Respiratory Papillomatosis: A Longitudinal Study Comparing Severity Associated With Human Papilloma Viral Types 6 and 11 and Other Risk Factors in a Large Pediatric Population

OBJECTIVES/HYPOTHESIS

A database was developed for prospective, longitudinal study of recurrent respiratory papillomatosis (RRP) in a large population of pediatric patients. Data recorded for each patient included epidemiological factors, human papilloma virus (HPV) type, clinical course, staged severity of disease at each surgical intervention, and frequency of surgical intervention. The study hypothesizes that patients with HPV type 11 (HPV-11) and patients younger than 3 years of age at diagnosis are at risk for more aggressive and extensive disease.

STUDY DESIGN

The 10-year prospective epidemiological study used disease staging for each patient with an original scoring system. Severity scores were updated at each surgical procedure.

METHODS

Parents of children with RRP referred to the authors' hospital completed a detailed epidemiological questionnaire at the initial visit or at the first return visit after the study began. At the first endoscopic debridement after study enrollment, tissue was obtained and submitted for HPV typing using polymerase chain reaction techniques and in situ hybridization. Staging of disease severity was performed in real time at each endoscopic procedure using an RRP scoring system developed by one of the authors (B.J.W.). The frequency of endoscopic operative debridement was recorded for each patient. Information in the database was analyzed to identify statistically significant relationships between extent of disease and/or HPV type, patient age at diagnosis, and selected epidemiological factors.

RESULTS

The study may represent the first longitudinal prospective analysis of a large pediatric RRP population. Fifty-eight of the 73 patients in the study underwent HPV typing. Patients infected with HPV-11 were significantly more likely to have higher severity scores, require more frequent surgical intervention, and require adjuvant therapy to control disease progression. In addition, patients with HPV-11 RRP were significantly more likely to develop tracheal disease, to require tracheotomy, and to develop pulmonary disease. Patients receiving a diagnosis of RRP before 3 years of age had significantly higher severity scores, higher frequencies of surgical intervention, and greater likelihood of requiring adjuvant medical therapy. Patients with Medicaid insurance had significantly higher severity scores and required more frequent surgical debridement. Birth by cesarean section appeared to be a significant risk factor for more severe disease and necessity of more frequent surgical intervention.

CONCLUSION

Statistical analysis of the relationships among epidemiological factors, HPV type, and clinical course revealed that patients with HPV-11 and patients younger than 3 years of age at RRP diagnosis are prone to develop more aggressive disease as represented by higher severity scores at endoscopic debridement, more frequent operative debridement procedures per year, a greater requirement for adjuvant therapy, and greater likelihood of tracheal disease with tracheotomy.

Recurrent respiratory papillomatosis: a review

Recurrent respiratory papillomatosis (RRP), which is caused by human papillomavirus types 6 and 11, is the most common benign neoplasm of the larynx among children and the second most frequent cause of childhood hoarseness. After changes in voice, stridor is the second most common symptom, first inspiratory and then biphasic. Less common presenting symptoms include chronic cough, recurrent pneumonia, failure to thrive, dyspnea, dysphagia, or acute respiratory distress, especially in infants with an upper respiratory tract infection. Differential diagnoses include asthma, croup, allergies, vocal nodules, or bronchitis. Reports estimate the incidence of RRP in the United States at 4.3 per 100,000 children and 1.8 per 100,000 adults. Infection in children has been associated with vertical transmission during vaginal delivery from an infected mother. Younger age at diagnosis is associated with more aggressive disease and the need for more frequent surgical procedures to decrease the airway burden. When surgical therapy is needed more frequently than four times in 12 months or there is evidence of RRP outside the larynx, adjuvant medical therapy should be considered. Adjuvant therapies that have been investigated include dietary supplements, control of extra-esophageal reflux disease, potent antiviral and chemotherapeutic agents, and photodynamic therapies; although several have shown promise, none to date has "cured" RRP, and some may have serious side effects. Because RRP, although histologically benign, is so difficult to control and can cause severe morbidity and death, better therapies are needed. The potential for a quadrivalent human papilloma vaccine is being explored to reduce the incidence of this disease.

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.

STUDY DESIGN

A prospective pilot study was performed in 55 adult patients with laryngeal papillomatosis to determine disease response.

METHODS

During suspension microlaryngoscopy, a solid-state 532 nm pulsed-KTP laser was used (15 ms pulse width, 5.25-7.5 J/pulse maximum output, 2 Hz repetition rate, 0.4 mm fiber, approximately 20-80 J/cm2 fluence) to treat laryngeal papillomatosis. All patients underwent postoperative videolaryngoscopy to assess disease regression based on a previously used rating scale.

RESULTS

Thirty-seven patients underwent 55 procedures during the 18-month study period. Near-term follow-up with an early postoperative evaluation was available in 23 patients (35 procedures). Fourteen patients (20 procedures) were geographically distant and only returned after developing symptoms with significant disease recurrence. Of the 35 procedures in which near-term follow-up was available, 90% or greater disease regression was achieved in 28 of 35 (80%), 75% to 89% disease regression was achieved in 4 of 35 (11%), and 50% to 74% disease regression in 3 of 35 (9%). Anterior-commissure disease was present in 51 of 55 (93%) cases, and no new webbing/synechia occurred. All patients reported that their vocal function improved after treatment.

CONCLUSIONS

The 532 nm pulsed-KTP laser was effective for treating recurrent respiratory papillomatosis, which was similar to our experience as an office-based procedure.

Office-based laryngeal laser surgery with local anesthesia

PURPOSE OF REVIEW

Office-based laryngeal laser surgery was created recently and is emerging as a reliable and practical method of treating a number of laryngeal lesions. This style of minimally invasive surgery is becoming increasingly popular in the United States and abroad.

RECENT FINDINGS

Fiber-based lasers and distal-chip flexible endoscopy have facilitated a new style of surgery. Epithelial diseases such as dysplasia and papillomatosis are well suited for treatment. Although the initial angiolytic laser used was a 585-nm pulsed-dye laser, the 532-nm pulsed-potassium-titanyl-phosphate laser has been demonstrated to be more effective. The 2013-nm Thulium laser shows promise as an office-based laser that simulates the properties of the carbon dioxide laser.

SUMMARY

Evolving technologies to enhance laryngoscopic imaging and lasers along with socioeconomic forces should lead to increasing numbers of laryngeal procedures being performed in the office with local anesthesia.

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.

STUDY DESIGN

The chick chorioallantoic membrane offers convenient access to many small blood vessels similar in size to those targeted in human vocal fold. Using a 532-nm pulsed KTP laser, pulse width, pulse energy, and working distance from the optical delivery fiber were varied to assess influence on the ability to achieve vessel coagulation without vessel wall rupture.

METHODS

Third-order vessels (n = 135) were irradiated: Energy (471-550 mJ), pulse width (10, 15, 30 ms), and fiber-to-tissue distance (1 mm, 3 mm) were varied systematically.

RESULTS

Selective vessel destruction without vessel wall rupture was more often achieved by increasing pulse width, increasing the fiber-to-tissue distance, and decreasing energy. Vessel destruction without rupture was consistently achieved using 15- or 30-ms pulses with a fiber-to-tissue distance of 3 mm (pulse fluence of 13-16 J/cm).

CONCLUSIONS

This study substantiates our clinical observation that a 532-nm pulsed KTP laser was effective for ablating microcirculation while minimizing vessel wall rupture and hemorrhage.

Recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis is a frustrating and challenging disease for surgeons, patients, and patients' families. Although the voice and airway manifestations are managed surgically, a "cure" for this disease remains elusive. In this edition of the "Seminar Series," we endeavor to review the current literature regarding the epidemiology, etiology, clinical manifestations, and surgical and medical treatments of this disorder. The key to future management of recurrent respiratory papillomatosis may lie in its prevention, if current efforts to develop an effective vaccine come to fruition.

Overview of recurrent respiratory papillomatosis

PURPOSE OF REVIEW

The purpose of this article is to review recent literature regarding pediatric recurrent respiratory papillomatosis (RRP) published within the last year. By reviewing and assessing these articles, a more clear understanding regarding the etiology and management of pediatric RRP can be obtained, allowing physicians to better care for their pediatric RRP patients.

RECENT FINDINGS

Pediatric RRP continues to be an extremely difficult management problem for otolaryngologists. This disease process continues to be a significant burden on the health care system and is a significant cause of morbidity in affected patients and their families. The incidence of RRP continues to be approximately 3.96 per 100,000 in the pediatric population. It has been noted recently that approximately 7 of every 1000 children born to mothers with vaginal condyloma develop pediatric RRP. Although the mainstay of surgical management has traditionally been the CO2 laser, newer surgical techniques have demonstrated efficacy in the management of pediatric RRP patients, including powered instrumentation and the pulse-dye laser. The traditional adjuvant medical therapies used for pediatric RRP continue to be commonly used, including interferon-alpha2a, retinoic acid, and indol-3-carbinol/diindolylmethane (I3C/DIM). Recently cidofovir has demonstrated efficacy in selected patients. In addition, current research regarding vaccine therapy for pediatric RRP has shown promise. Basic science research in the field of immunology has demonstrated multiple defects in cell-mediated immunity, which has shed further light on the etiology of pediatric RRP.

SUMMARY

Pediatric RRP continues to be a highly morbid disease process. New surgical and medical therapies offer hope for better control of this disease in affected patients. Recent advances in immunologic research offer the hope of immune system modulation and augmentation as potential future treatment modalities to better control this disease process.

Novel treatments for recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis is a rare but often severe disease. Although benign in histology, epithelial proliferations may result in progressive hoarseness, stridor, obstruction of the airway and respiratory distress. The current standard of care is surgical therapy with a goal of complete removal or debulking of papillomas and preservation of normal structures. Frequent recurrences and the need for repeated surgical interventions make this treatment a frustrating experience for both the patient and the physician. Many adjuvant therapies have been investigated but no single treatment modality proved to be effective in eradicating recurrent respiratory papillomatosis. In contrast to HIV, cytomegalovirus and hepatitis B pharmaceutical research has been less successful with human papilloma virus vaccines for a variety of reasons. This review focuses on the current status of recurrent respiratory papillomatosis and on future directions of prevention and therapy.

585-nm pulsed dye laser treatment of glottal papillomatosis

Treatment of recurrent respiratory papillomatosis of the glottis is often challenging. The surgeon and patient must cooperatively balance decisions regarding airway safety, effects of multiple general anesthesias, employment disturbance, and vocal dysfunction. A pilot study was done in 41 adult cases (23 patients; 78 vocal folds) without complication to evaluate the effectiveness of a 585-nm pulsed dye laser (PDL; 450-micros pulse width; fluence of 38 to 255 J/cm2; 1- to 2-mm spot size) in the treatment of this disorder. Thirty-seven of the 41 cases (90%) were bilateral disease. Twenty-six of the 41 cases (63%; including 20 cases with involvement of the anterior commissure) were treated by bilateral photocoagulation of the lesions' microcirculation without microflap resection of tissue. Clinical observation revealed that irradiated but unresected disease involuted without development of an anterior commissure web. In the initial 13 of the 41 cases (32%), PDL treatment was followed by cold instrument microflap resection. The PDL enhanced the epithelial excision by improving hemostasis and by creating an optimal dissection plane between the basement membrane and the underlying superficial lamina propria. The PDL at 585 nm was less effective in the management of exophytic lesions because of its limited depth of penetration (approximately 2 mm). In this initial trial, the PDL was a relatively safe and efficacious treatment for glottal recurrent respiratory papillomatosis. Since the lesions involute without complete resection of the diseased epithelium, the anterior commissure can be treated to minimize the number of procedures. To study patterns of recurrence will require longer follow-up.

Human papillomavirus in larynx

OBJECTIVES

The core of the present clinical and basic research knowledge of laryngeal human papillomavirus (HPV) infection is described.

STUDY DESIGN

Review.

METHODS

A computer-aided search of MEDLINE database supplemented by hand searches of key journals was conducted.

RESULTS

One of the tumor-promoting factors in the larynx is the HPV found both in normal laryngeal epithelium and in laryngeal tumors. The most important manifestation of laryngeal HPV infection is laryngeal papillomatosis, a rare disease caused by HPV types 6 and 11. In laryngeal carcinogenesis, the role of HPV remains uncertain. The means of transmission of HPV are partly unknown, and the course of laryngeal HPV infection is unpredictable and variable. Treatment of laryngeal papillomatosis is based on surgery, especially on CO2 laser and shaver. Alpha-interferon is the drug of choice in patients whose response to surgery is poor. However, neither interferon nor other antiviral drugs are able to eradicate the virus from laryngeal mucosa. Little is known about immunological mechanisms involved in laryngeal HPV infection, but in defense against HPV cellular immunity is considered a more important mechanism than humoral immunity. A good experimental model of HPV infection is lacking in which the entire viral life cycle can take place. Organotypic cell cultures (collagen rafts) are useful, but the rate-limiting step in this method is the difficulties in culturing HPV-positive epithelial cells.

CONCLUSIONS

Although laryngeal papillomatosis is clinically well defined, the mechanisms and treatment modalities of laryngeal HPV infection need further investigations.

CO(2) laser treatment in 244 patients with respiratory papillomas

OBJECTIVE

Respiratory papillomas (RP) tend to recur and the difficulty in eradicating the disease makes their treatment frustrating. Meticulous CO(2) laser excisions every 2 months has been the most effective treatment to date. This article analyzes the results of this plan in 244 patients with RP in the nose, nasopharynx, pharynx, hypopharynx, larynx, trachea, lung parenchyma, and skin.

METHODS

Two hundred forty-four patients with recurrent RP were treated by the senior author with CO(2) laser excisions and, in some cases, podophyllum and alpha interferon. Demographics, initial distribution of papillomas, number of operations performed on each patient, and current results were evaluated.

RESULTS

Careful laser excisions of RPs every 2 months achieved "remission" of disease (no visible RP on indirect or often direct laryngoscopy 2 mo after last removal) in 37% of patients, "clearance" of the disease process (no RP clinically apparent for 3 y after last removal) in 6%, and "cure" (no clinical recurrence for 5 y after last removal) in 17%. Juvenile-onset RP tends to follow a more aggressive course than adult-onset RP. Four patients (1.6%) developed malignant transformation of their papillomas. Except for ones in lung parenchyma, RP in areas other than the true vocal cords tend to be cleared faster because aggressive removal does not cause hoarseness. Lung parenchyma RPs are eventually fatal because of pulmonary failure from abscesses and cysts resulting from a lack of effective treatment.

CONCLUSION

Frequent and meticulously performed CO(2) laser excisions can achieve significant voice and airway improvement, and some clinical "cures." However, effective antiviral medicines and/or immunologic agents are needed to achieve true cures with elimination of all human papilloma virus 6 and 11 viruses.

A new laser treatment for vocal cord papilloma--585-nm pulsed dye

OBJECTIVES

Microvascular targeting with the 585- nm pulsed dye laser (PDL) may provide a new form of therapy to control symptoms caused by recurrent respiratory papillomatosis (RRP).

METHODS

Ten patients with RRP underwent 13 procedures under general anesthesia with the 585-nm PDL. A micromanipulator (11 procedures) and a flexible nasolaryngoscope (2 procedures) were used to deliver the laser pulses. Patients were followed postoperatively according to protocol.

RESULTS

Clinical examination revealed regression of papillomas in all patients. Seven patients had complete regression after PDL surgery, and 2 patients had partial response to treatment. One patient was lost to follow-up. No complications were present during this prospective nonrandomized pilot study.

CONCLUSION

Patients treated with PDL experienced regression of their papillomas. PDL may provide patients with RRP with an alternative treatment without the risks associated with CO(2) laser surgery. This procedure also has potential to be delivered on an outpatient basis with flexible fiberoptic laryngoscopes.

Recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is the most common benign neoplasm of the larynx in children. Despite its benign histology, RRP has potentially morbid consequences and is often difficult to treat because of its tendency to recur and spread throughout the respiratory tract. Long neglected from an epidemiological standpoint, recent initiatives to better understand this disease process have been launched through coordination between the Centers for Disease Control and Prevention and the American Society of Pediatric Otolaryngology. In this clinical review, I discuss what we currently know regarding the etiology, epidemiology, and transmission of this disease. Clinical features including pertinent aspects of the history, physical examination, airway endoscopy, and other considerations are highlighted. A detailed description of the surgical and anesthetic management of these challenging cases is presented. Adjuvant modalities of surgical and nonsurgical treatment and their indications are discussed. Ongoing research initiatives and the Practice Guidelines of the Recurrent Respiratory Papillomatosis Task Force are also included.

Recurrent respiratory papillomatosis of the larynx: current diagnosis and treatment

Treating children with recurrent respiratory papillomatosis can be very rewarding as more information is learned about human papillomavirus. The future goals are reducing the morbidity and mortality of this disease process. The establishment of the national recurrent respiratory papillomatosis patient registry and coordinated efforts between basic scientists involved in human papillomavirus research and clinicians involved in the treatment of recurrent respiratory papillomatosis should aid the endeavor.

Advances and refinements in phonosurgery

Scientific discovery, technological advances, and improved outcomes assessment have resulted in advances and refinements in phonosurgery. Three areas of substantial evolution are phonomicrosurgery, laryngeal framework surgery, and the use of implantable materials in vocal folds. Discovery of the importance of the superficial layers of the lamina propria has led to increased use of more limited medial microflap approaches and less frequent use of the classic lateral cordotomy flap approach. Alternative approaches to managing vocal fold scarring defects have addressed the separation of body and cover and provided suitable lamina propria replacement. Approaches to sulcus vocalis have been refined to address type II (linear vergeture) and type III (focal invasive pit) sulcus, where there is loss of lamina propria, while still recognizing the common nonpathological type I (physiological) sulcus. Technological advancements such as photodynamic therapy, tuned dye lasers, and laryngeal microdebridement have augmented the armamentarium for mechanical removal of laryngeal papillomata. Careful infusion-assisted microexcision and adjunctive medical management have been refined and made more effective. Laryngeal framework surgery has embraced the development of Silastic, hydroxylapatite, expanded polytetrafluoroethylene, and titanium shims. Anatomical studies have helped to improve operative precision and safety, and have led to inventive variations in arytenoid repositioning that improve closure of the posterior subunit. Vocal fold augmentation by injection has been facilitated by innovative use of the rigid telescope and intraoperative videostroboscopy. Anatomical studies have focused on the infrafold region and rheological studies have attempted to match viscoelastic properties of injectable substances to those of vocal fold tissues. Alloplastic materials such as Teflon have been largely supplanted by newer bioimplantables such as fat, collagen, and fascia.