Pediatric rhabdomyosarcoma of the head and neck

Pediatric rhabdomyosarcoma is not exclusive to the head and neck. However, the unique anatomy of the head and neck requires special consideration and treatment modifications. The low incidence of these tumors has prevented the development of rigorous treatment protocols. Treatment strategies must be individualized on the basis of histopathologic subtype, prognostic indicators, tumor location, tumor extent, available clinical trial data, and hospital resources. The primary treatment of these tumors typically involves a combination of surgery, radiation, and chemotherapy. Advancements in surgical and radiotherapy techniques have reduced patient morbidity, whereas new chemotherapeutic protocols have improved local disease control and overall survival. Because of the infrequency and complexity of these tumors, patients may benefit from referral to centers with a comprehensive multidisciplinary team that has experience treating these tumors in the pediatric population. If possible, patients should be enrolled and treated on the current Children's Oncology Group protocol.

Role of mitomycin in upper digestive tract stricture

BACKGROUND

Mitomycin C is an anti-fibroblast chemotherapeutic agent that has demonstrated promise in the treatment of head and neck cancer-related cervical stenosis. The present study investigates whether the application of mitomycin C at the time of dilation is both safe and effective in the treatment of head and neck cancer-related upper digestive tract stricture.

METHODS

Twelve patients with progressive dysphagia and video-fluoroscopic evidence of upper digestive tract stricture after head and neck cancer treatment were dilated by Maloney or Savory dilators followed by the application of mitomycin C (0.2 mg/0.4 mL saline) to the stenotic segment for 5 minutes. Outcome measures included complication rate, improvement in baseline dietary consistency, and improvement in swallowing-related quality of life as measured by the M. D. Anderson Dysphagia Inventory.

RESULTS

All patients experienced improvement in their baseline dietary consistency (p = .002) and M. D. Anderson Dysphagia Inventory composite score (p = .001) after a mean follow-up time of 19 months. No complications from mitomycin use were observed.

CONCLUSION

Mitomycin application appears to be a safe and potentially effective treatment for head and neck cancer-related upper digestive tract stricture. Given the small sample size and limited follow-up time, a randomized, controlled trial is needed to determine whether mitomycin application offers additional benefit over standard dilation therapy.

Muscle-sparing abdominal free flaps in head and neck reconstruction

BACKGROUND

Our aim in this retrospective case series was to review the indications, results, and complications of abdominal muscle-sparing free flaps in head and neck cancer reconstruction.

METHODS

A retrospective review of all head and neck cancer defects reconstructed with abdominal muscle-sparing free tissue transfers from 1999 to 2004 was performed. Data collected included patient demographics, etiology and site of the defect, reconstructive technique, flap size, recipient vessels, complications, reconstructive technique, and clinical follow-up.

RESULTS

Sixteen patients underwent reconstruction with the deep inferior epigastric perforator (DIEP) flap (n = 11), the superficial inferior epigastric artery (SIEA) flap (n = 4), or the superficial circumflex iliac artery (SCIA) flap (n = 1). Average age was 61 years (range, 41-77 years). The average hospital stay was 7.6 days (range, 6-14 days). The average defect size was 74.5 cm(2) (range, 30-240 cm(2)). No subsequent abdominal wall hernias or other donor site complications occurred after a mean follow-up of 21 months.

CONCLUSIONS

Muscle-sparing abdominal free flaps are attractive options for head and neck cancer reconstruction. The SIEA and SCIA free flaps have the distinct advantage of eliminating abdominal hernias and other morbidity related to the excision of rectus abdominus fascia or muscle. In addition, the incisions are very low on the abdomen and are more cosmetically pleasing to the patient.

Laryngeal Penetration and Aspiration During Swallowing After the Treatment of Advanced Oropharyngeal Cancer

OBJECTIVE

To determine whether laryngeal penetration and aspiration in oropharyngeal cancer survivors differ by treatment group.

DESIGN

Cross-sectional study of patients with stage III or IV oropharyngeal squamous cell carcinoma who were at least 12 months removed from combined modality therapy and clinically free of disease.

SUBJECTS

Potential subjects were stratified by tumor site and tumor T stage to achieve a similar comparison between chemoradiotherapy (n = 10) and surgery/radiotherapy (n = 11) groups. Validated instruments used to evaluate swallowing included the Penetration-Aspiration Scale and the M. D. Anderson Dysphagia Inventory.

RESULTS

Patients with oropharyngeal cancer treated with chemoradiotherapy demonstrated greater airway protection according to Penetration-Aspiration Scale scores than those treated with surgery and radiotherapy on 5-mL (P = .02), 10-mL (P = .04), and 20-mL (P = .04) liquid barium swallows. Also, the oropharyngeal chemoradiotherapy group had better self-perceived swallowing ability than the surgery-radiotherapy group on the basis of the M. D. Anderson Dysphagia Inventory (P = .02).

CONCLUSION

The present study suggests that patients with oropharyngeal cancer who successfully complete chemoradiotherapy protocols without surgical salvage retain greater airway protection during swallowing and better swallowing-related quality of life than patients treated with primary surgery and radiotherapy.

Management of paranasal sinus malignancy

Malignancies of the nasal cavity and paranasal sinuses represent a wide spectrum of histologies, tissues of origin, and anatomic primary sites. The inherent difficulty in generalizing treatment approaches is obvious, given the numerous variables associated with the broadly-based term, paranasal sinus malignancy (PNSCa). Nevertheless, the majority of epithelial and salivary malignancies of this region (ie, squamous cell carcinoma, adenocarcinoma, adenoid cystic carcinoma, sinonasal undifferentiated carcinoma, and esthesioneuroblastoma) require surgical intervention as part of any treatment regimen. Recent trends have broadened the indications for chemotherapeutic and radiotherapeutic options in the management of advanced PNSCa. Nonepithelial malignancies, including the wide variety of sarcomas arising in this region, most commonly require multimodality treatment including chemotherapy, radiation, and/or surgery for definitive treatment. Moreover, the proximity of the nasal cavity and paranasal sinuses to structures including the orbit, dura, brain, cranial nerves, and carotid arteries mandates careful radiologic and neurologic evaluations throughout the course of the disease. Surgical advances now permit complex tumor removal and reconstruction surrounding these structures resulting in functional and cosmetic improvements when compared to earlier techniques. However, additional clinical trials are necessary to systematically evaluate the locoregional control, organ-preservation strategies, and survival related to the variety of treatments currently available.

Melanoma of the head and neck

Staging of cutaneous melanoma has changed in recent years with an increased emphasis upon thickness and ulceration on prognosis of early stage disease. Cutaneous melanoma of the head and neck is treated with complete surgical resection in early stage disease. Resection margins are determined by the size, depth, and presence of satellite lesions. Evaluation for regional and distant metastatic disease is necessary in all cases of advanced stage disease. Sentinel lymph node biopsy and possible parotidectomy and neck dissection should be considered in head and neck cutaneous melanomas greater than 1 mm in thickness or with ulceration. Adjuvant therapy may be indicated in advanced primary, nodal, and metastatic disease. Mucosal melanoma of the head and neck remains a difficult disease to treat, with high locoregional recurrence rates and poor prognosis despite aggressive therapy.

Pharmacologic management of chronic rhinosinusitis, alone or with nasal polyposis

Patients with chronic rhinosinusitis (CRS) and chronic rhinosinusitis with nasal polyposis (CRSwNP) commonly present with nasal obstruction, nasal discharge, facial pressure/pain, and hyposmia of prolonged duration. Recent evidence suggests that, despite clinical similarities, CRS and CRSwNP are distinct entities with separate inflammatory pathways and cytokine profiles. Antibiotics and nasal steroids are the mainstay of treatment in CRS, whereas combination systemic and nasal steroids are the foundation of CRSwNP management. Allergy therapy may play a significant role in CRS, whereas antileukotriene therapy has demonstrated promise in CRSwNP. Although prolonged medical therapy is usually necessary with both disorders, surgery may also be required to relieve refractory symptoms, and to improve sinus aeration and nasal access for topical therapy.

Swallowing-related quality of life after head and neck cancer treatment

OBJECTIVES

To determine the role of treatment modality in swallowing outcome after head and neck cancer treatment and to identify potential risk factors for posttreatment dysphagia.

STUDY DESIGN

Cross-sectional survey of patients with no evidence of disease 12 months or more after the treatment of a stage III or IV squamous cell carcinoma of the oropharynx, larynx, or hypopharynx.

METHODS

Potential subjects were stratified by tumor site and tumor T-stage to achieve a balanced comparison between chemoradiation (n = 18) and surgery/radiation (n = 22) groups. Outcome measures included a dysphagia risk factor survey, the MD Anderson Dysphagia Inventory (MDADI), and the Short-Form 36 (SF-36).

RESULTS

Patients who received chemoradiation for oropharyngeal primaries demonstrated significantly better scores on the emotional (P =.03) and functional (P =.02) subscales of the MDADI than did patients who underwent surgery followed by radiation. There were no significant differences between chemoradiation and surgery/radiation groups for laryngeal and hypopharyngeal primaries. Additional risk factors for posttreatment dysphagia include prolonged (>2 weeks) nothing by mouth (NPO) status (P =.002) and low SF-36 Mental Health Subscale score (P =.002).

CONCLUSION

The study suggests that chemoradiation may provide superior swallowing outcome to surgery/radiation in patients with oropharyngeal primary. Patients with depressed mental health and prolonged feeding tubes may be at higher risk of long-term dysphagia.

The Canalith Repositioning Procedure for Benign Positional Vertigo: A Meta-Analysis

OBJECTIVE

To review the effectiveness of the canalith repositioning procedure (CRP) in the treatment of benign paroxysmal positional vertigo (BPPV) with a critical review of the literature and meta-analysis.

STUDY DESIGN

Meta-analysis.

METHODS

Studies eligible for inclusion were randomized, controlled trials of the CRP performed on clearly defined cases of BPPV. A total of nine studies meeting inclusion criteria were identified by two independent literature searches of Medline. Treatment and control groups were compared for symptom resolution and elimination of a positive Dix-Hallpike test.

RESULTS

Patients treated with CRP were more likely to demonstrate symptom resolution (odds ratio [OR] 4.6; 95% confidence interval [CI] 2.8-7.6) and negative Dix-Hallpike (OR 5.2; 95% CI 3.0-8.8) at the time of first follow-up. The effect of CRP for symptom improvement was strongest within the first month after treatment (OR 4.1; 95% CI 3.1-5.2) with some decline thereafter (OR 2.8; 95% CI 1.7-3.9). Conversely, the ability of CRP to produce a negative Dix-Hallpike strengthened between the first month after treatment (OR 3.0; 95% CI 1.8-4.0) and later follow-up times (OR 5.0; 95% CI 3.9-6.1).

CONCLUSIONS

The CRP is more effective than control in resolving vertigo and positive Dix-Hallpike associated with BPPV. This finding was consistent among a variety of studies using different study designs. Untreated patients may demonstrate symptom improvement with time; however, many will continue to have a positive Dix-Hallpike when examined. Resolution of vertigo in untreated patients is therefore most likely because of avoidance of provocative positions.

Research subject privacy protection in otolaryngology

BACKGROUND

Health Insurance Portability and Accountability Act regulations, which took effect on April 14, 2003, placed new constraints on the use of protected health information for research purposes.

OBJECTIVE

To review practices of research subject privacy protection in otolaryngology in order to determine steps necessary to achieve compliance with Health Insurance Portability and Accountability Act regulations.

STUDY DESIGN

Literature review.

METHODS

Articles appearing in 2001 in 3 widely circulated otolaryngology journals were classified according to study design. The "Methods" section of each article was reviewed to determine whether the informed consent and institutional review board processes were clearly documented.

RESULTS

Descriptive studies involving case reports and case series were more common than observational studies that include a control group (66% vs 11%). Few case series documented the consent process (18%) and institutional review board process (19%). Observational designs demonstrated better documentation of the consent process (P<.001) and the institutional review board exemption and approval process (P<.001).

CONCLUSIONS

Methods used to protect subject privacy are not commonly documented in case series in otolaryngology. More attention needs to be given to research subject privacy concerns in the otolaryngology literature in order to comply with Health Insurance Portability and Accountability Act regulations.

Salivary gland neoplasms

Treatment and cure of salivary gland neoplasms requires surgical intervention in most cases. For parotid neoplasms, the most common surgical procedure performed is the superficial parotidectomy with facial nerve preservation. Postoperative radiation therapy is indicated in high-grade salivary gland malignancies and malignancies with increased risk of locoregional recurrence. Primary radiation, including neutron beam techniques, may play a role in certain histologic types or nonoperative candidates. Chemotherapy has yet to result in improvements in survival or quality of life in the treatment of salivary gland malignancy. Advances in radiation therapy techniques, including intensity-modulated radiation therapy, provide opportunities for reduced morbidity.

Value-based approach to power-assisted adenoidectomy

A recognized disadvantage of power-assisted adenoidectomy (PAA) is the increased patient charge associated with the disposable instrumentation. The elimination of pathological review of routine adenoid specimens may provide a means of offsetting the increased charge, as 1) unsuspected findings are rare, and 2) PAA specimens are too traumatized to provide the microscopic detail necessary to make an unsuspected diagnosis. The pathology reports of all adenoidectomy specimens removed over a 10-year period were reviewed and combined with previously published reviews in order to estimate the prevalence of unsuspected disease. The estimated prevalence of unsuspected diagnoses found by routine pathological review of adenoid specimens is 37 per 100,000 cases (95% confidence interval, 26-51). In a separate analysis, a pathologist blinded to the technique of adenoid removal assessed the tissue effects of curette adenoidectomy versus PAA. Significant tissue damage at the microscopic level was identified in 6 of 11 specimens removed with the power-assisted technique as compared to 0 of 11 specimens removed by curette (p = .03). Eliminating histopathologic review of routine adenoidectomy specimens can potentially offset the increased patient charge of PAA by 62%. Power-assisted adenoidectomy, however, should be avoided in nonroutine cases in which the potential for occult disease exists.

Oral cancer treatment

Oral cancer is the sixth most common cancer in the world, and it continues to represent a serious public health problem. Oral cancer is a preventable disease, related to behavioral and lifestyle factors, including tobacco and alcohol. Prevention and early detection of oral cancer remain the goals of national efforts to reduce the impact of this disease on the public. Surgical treatment is the mainstay of therapy for patients with oral cancer, particularly in advanced stages of cancer. External beam radiation therapy and brachytherapy have been used successfully as the primary modality for treating patients with early stage oral cancer, and they are the standard of care for use as adjuvant therapy in postoperative cases of patients with advanced stage oral cancer. There is an emerging trend for the use of chemotherapy in combination with radiation therapy and surgery for patients with advanced, recurrent, and metastatic head and neck cancer, although evidence is limited regarding survival benefit when used for treating patients with oral cavity carcinoma. Any report on the treatment of oral cancer is incomplete without consideration of functional and aesthetic outcomes, particularly addressing speech, swallowing, masticatory efficiency, and dental rehabilitation. Future generations will continue to fight these dreadful diseases until scientists and clinicians are provided the opportunities to expand efforts to prevent, detect (early), and eradicate oral and other head and neck cancers.

Obstructive sleep apnea: a comparison of black and white subjects

OBJECTIVE

To determine if the severity of obstructive sleep apnea syndrome (OSA) differs by racial group.

STUDY DESIGN

Cross-sectional retrospective review.

SETTING

University-based sleep disorders laboratory.

METHODS

The study reviewed the results of 280 adult (>18 y) patients diagnosed with obstructive sleep apnea syndrome by overnight polysomnogram between July 1, 1999, and June 30, 2000. Factors analyzed included age, sex, race, presence of hypertension, body mass index (kg/m2), respiratory disturbance index (RDI), and lowest oxygen saturation level.

RESULTS

Blacks with OSA are significantly more obese and have significantly higher rates of hypertension than white subjects with OSA. Black females with OSA are significantly younger than white females at the time of diagnosis (P =.005). Black males with OSA have significantly lower oxygen saturations than white males (P =.025).

CONCLUSION

Black males who present to the otolaryngologist-head and neck surgeon for evaluation of sleep-disordered breathing may be at increased risk of severe OSA.

Squamous cell carcinoma of the temporal bone: a radiographic-pathologic correlation

OBJECTIVE

To assess the utility of a previously proposed staging system for patients with primary squamous cell carcinoma of the temporal bone.

METHODS

Retrospective chart review of 15 patients treated for squamous cell carcinoma of the temporal bone over a 13-year period at an academic tertiary referral center. A review of the medical and surgical records, radiographic studies, and surgical pathology reports allowed for an evaluation of the University of Pittsburgh staging system. Outcome analysis was performed on 13 patients with more than 24 months of follow-up.

RESULTS

Radiographic and surgical pathology staging according to the University of Pittsburgh staging system correlated in 11 (73%) of 15 cases. The radiographic staging system was more accurate for larger (T3/T4) tumors than for smaller (T1/T2) tumors (83% vs 67%). When compared with patients with no evidence of disease, nonsurvivors were more likely to present with otalgia (67% vs 43%), facial nerve paralysis (33% vs 0%), and T3/T4 tumors (100% vs 14%).

CONCLUSIONS

Pathologic staging by the University of Pittsburgh staging system closely correlates with patient outcome and is more sensitive than preoperative radiographic staging. Prognosis in squamous cell carcinoma of the temporal bone is largely determined by the extent of local disease at the time of presentation.

Role of middle turbinate biopsy in the diagnosis of fulminant invasive fungal rhinosinusitis

OBJECTIVE

To determine the efficacy of middle turbinate biopsy in the diagnosis of fulminant invasive fungal rhinosinusitis.

STUDY DESIGN

Nonrandomized prospective study.

METHODS

Directed middle turbinate biopsy was performed in 25 patients suspected of having fulminant invasive fungal rhinosinusitis. All patients were immunocompromised and had fever of unknown origin, symptoms of rhinosinusitis, or both.

RESULTS

Six patients were found to have fungal invasion on histopathological review (6 true-positive findings), disease developed in 2 patients with negative results on biopsy (2 false-negative findings), and disease never developed in 17 patients with negative results on biopsy (17 true-negative findings), resulting in an overall sensitivity of 75% and a specificity of 100%.

CONCLUSIONS

Middle turbinate biopsy is a safe and effective method of making a timely diagnosis of fulminant invasive fungal rhinosinusitis. The added morbidity and cost of surgery can be avoided in the patient with a negative finding on biopsy. However, the effect of earlier diagnosis on overall patient survival is unclear at present.

An algorithmic approach to the diagnosis and management of invasive fungal rhinosinusitis in the immunocompromised patient

Acute invasive fungal rhinosinusitis is a difficult disorder to diagnose and treat. A systematic approach to the susceptible patient, however, leads to an earlier diagnosis with improved survival. Early evaluation with rigid nasal endoscopy with frozen section biopsy of suspicious lesions or the middle turbinate should be considered in the high-risk population. Complete surgical resection and the reversal of neutropenia appear to be critical elements in achieving a successful outcome in patients with invasive fungal rhinosinusitis.

The uvulopalatal flap for reconstruction of the soft palate

OBJECTIVE

To determine the indications, complications, and outcomes of the uvulopalatal flap in the reconstruction of defects of the soft palate.

STUDY DESIGN

Retrospective review.

METHODS

Patient data were obtained from the hospital records of 18 patients who had soft palate defects reconstructed with the uvulopalatal flap over a 5-year period at a tertiary academic medical center.

RESULTS

Eleven patients had the uvulopalatal flap as the sole method of reconstruction, whereas this flap was used in combination with a radial forearm free flap, pectoralis flap, and skin graft in 4, 2, and 1 patients, respectively. All flaps were successful in soft palate reconstruction. One flap was successfully revised after additional tumor resection. A partial flap dehiscence occurred in one patient and healed uneventfully. Speech and swallowing function was dependent on initial tumor stage and the scope of tumor resection.

CONCLUSIONS

The uvulopalatal flap is a simple and effective method of soft palate reconstruction either alone or in combination with other methods of reconstruction for selected oropharyngeal defects.

Outcomes of emergency surgical airway procedures in a hospital-wide setting

OBJECTIVE

To review the circumstances, complications, and outcomes of emergency surgical airway procedures and to compare the relative merits of cricothyroidotomy and tracheotomy for airway control in a hospital-wide patient population.

STUDY DESIGN

Retrospective review.

METHODS

Patient data were obtained from the inpatient charts and electronic patient records of 35 patients who required an emergency surgical airway over a 6-year period at an urban medical center.

RESULTS

Emergency cricothyroidotomy and tracheotomy were successfully performed in 34 of 35 patients (97%). Orotracheal intubation was successfully achieved in one patient with a failed cricothyroidotomy. The overall complication rates for emergency cricothyroidotomy and tracheotomy were similar (20% and 21%, respectively). Inpatients requiring an emergency surgical airway had a higher complication rate (32% vs. 0%) but better overall survival (91% vs. 46%) than patients treated in the emergency department. No long-term complications were observed from emergency cricothyroidotomies that were not converted to tracheotomies.

CONCLUSION

The establishment of an emergency surgical airway by either tracheotomy or cricothyroidotomy is effective with low overall morbidity. The need to convert every emergency cricothyroidotomy to a tracheotomy should be reevaluated.

Glycine immunoreactivity of multipolar neurons in the ventral cochlear nucleus which project to the dorsal cochlear nucleus

Certain distinct populations of neurons in the dorsal cochlear nucleus are inhibited by a neural source that is responsive to a wide range of acoustic frequencies. In this study, we examined the glycine immunoreactivity of two types of ventral cochlear nucleus neurons (planar and radiate) in the rat which project to the dorsal cochlear nucleus (DCN) and thus, might be responsible for this inhibition. Previously, we proposed that planar neurons provided a tonotopic and narrowly tuned input to the DCN, whereas radiate neurons provided a broadly tuned input and thus, were strong candidates as the source of broadband inhibition (Doucet and Ryugo [1997] J. Comp. Neurol. 385:245-264). We tested this idea by combining retrograde labeling and glycine immunohistochemical protocols. Planar and radiate neurons were first retrogradely labeled by injecting biotinylated dextran amine into a restricted region of the dorsal cochlear nucleus. The labeled cells were visualized using streptavidin conjugated to indocarbocyanine (Cy3), a fluorescent marker. Sections that contained planar or radiate neurons were then processed for glycine immunocytochemistry using diaminobenzidine as the chromogen. Immunostaining of planar neurons was light, comparable to that of excitatory neurons (pyramidal neurons in the DCN), whereas immunostaining of radiate neurons was dark, comparable to that of glycinergic neurons (cartwheel cells in the dorsal cochlear nucleus and principal cells in the medial nucleus of the trapezoid body). These results are consistent with the hypothesis that radiate neurons in the ventral cochlear nucleus subserve the wideband inhibition observed in the dorsal cochlear nucleus.

Prognosis in bilateral vestibular hypofunction

OBJECTIVES/HYPOTHESES

The outcomes of patients with bilateral vestibular hypofunction vary widely. Some resume relatively normal activity within months, whereas others have a more debilitated course. This study sought to identify factors that may affect outcome.

STUDY DESIGN

A retrospective review of patients treated for bilateral vestibular hypofunction over a 2-year period at a neurotology clinic.

METHODS

Patients' medical charts, electronystagmography data, rotatory chair testing, and posturography results were reviewed. Subjective and objective measures were used to evaluate outcome.

RESULTS

Bilateral vestibular hypofunction was diagnosed in 35 patients. Improvement after vestibular rehabilitation therapy was noted in 18 patients (51%), whereas 12 (34%) showed little or no change and 5 (15%) were not available for follow-up. The patients without improvement were more likely to have a chronic disorder as a cause of the vestibulopathy and had more medical comorbidities, on average, when compared with those who improved. Lower gains and time constants on rotatory chair testing were also seen in the group that did not improve.

CONCLUSIONS

Poor rehabilitation results may be attributable to increased severity of vestibular insult, progressive peripheral or central vestibular dysfunction, and multiple medical problems.

An approach to fulminant invasive fungal rhinosinusitis in the immunocompromised host

OBJECTIVE

To examine the pathogenesis of fulminant invasive fungal rhinosinusitis to determine factors that may affect patient survival.

METHODS

Retrospective chart review of 25 patients treated for invasive fungal rhinosinusitis over a 10-year period at an academic tertiary referral center. Evaluation of the medical and surgical records, radiographic studies, surgical pathology specimens, and culture results allowed for a multifactorial comparison between survivors and nonsurvivors. Survivors were patients who left the hospital with the invasive fungal disease stable or cured.

RESULTS

Fungal invasion often occurs within the nasal cavity (92% of patients), most commonly at the middle turbinate (62% of patients receiving biopsy). Survivors had complete surgical resection more often than nonsurvivors (90% vs 0%), and were more likely to respond to granulocyte colony-stimulating factor than nonsurvivors (100% vs 0% of those treated).

CONCLUSIONS

Rigid nasal endoscopy with frozen section biopsy of suspicious nasal lesions and high-incidence areas (ie, middle turbinate) allows for the timely diagnosis of invasive fungal rhinosinusitis. Survival improves if the disease is limited to the nasal or sinus cavities, which may represent an earlier stage of disease. Favorable prognostic signs include the ability to achieve a complete surgical resection and a positive response to granulocyte colony-stimulating factor in the neutropenic patient.

Effect of blood pressure changes on air flow dynamics in the upper airway of the decerebrate cat

BACKGROUND

Previous studies suggest that upper airway neuromuscular activity can be affected by changes in blood pressure via a baroreceptor-mediated mechanism. It was hypothesized that increases in blood pressure would increase upper airway collapsibility predisposing to airway obstruction at a flow-limiting site in the hypopharynx.

METHODS

To examine the effect of blood pressure on upper airway function, maximal inspiratory air flow was determined through the isolated feline upper airway before, during, and after intravenous infusion of phenylephrine (10-20 micrograms.kg-1.min) in six decerebrate, tracheotomized cats. Inspiratory flow, hypopharyngeal pressure, and pressure at the site of pharyngeal collapse were recorded as hypopharyngeal pressure was rapidly decreased to achieve inspiratory flow limitation in the isolated upper airway. Pressure-flow relationships were used to determine maximal inspiratory air flow and its mechanical determinants, the upper airway critical pressure (a measure of pharyngeal collapsibility), and the nasal resistance upstream to the site of flow limitation.

RESULTS

An increased mean arterial blood pressure of 71 +/- 16 mmHg (mean +/- SD) was associated with significant decrease in maximal inspiratory air flow from 147 +/- 38 ml/s to 115 +/- 27 ml.sec-1 (P < 0.01). The decrease in maximal inspiratory air flow was associated with an increase in upper airway critical pressure from -8.1 +/- 3.8 to -5.7 +/- 3.7 cm H2O (p < 0.02), with no significant change in nasal resistance. When blood pressure was decreased to baseline by discontinuing the phenylephrine infusion, maximal inspiratory air flow and upper airway critical pressure returned to their baseline values.

CONCLUSIONS

Increased blood pressure increased the severity of upper airway air flow obstruction by increasing pharyngeal collapsibility. Previous studies relating baroreceptor activity to neuromuscular regulation of upper airway tone, are consistent with this effect being mediated by afferent activity from baroreceptors. These findings warrant further study because they suggest the possibility that upper airway obstruction in postoperative patients could either be caused or exacerbated by an increase in blood pressure.

Diagnosis and treatment of obstructive sleep apnea of the larynx

To determine the mechanism for obstructive sleep apnea in two patients with clinical abnormalities of laryngeal function, airflow dynamics during sleep were analyzed. The site of airway obstruction was assessed by examining pressure gradients across specific airway segments. The relation between maximal inspiratory airflow and nasal pressure was analyzed to determine (1) the critical pressure, a measure of the collapsibility of the laryngeal airway, and (2) the effect of nasal continuous positive airway pressure on airflow during sleep. Large inspiratory pressure gradients developed during sleep between the supraglottic and pleural spaces, indicating that collapse had occurred in the larynx. Elevated critical pressures of -6.4 and +1.2 cm H2O, respectively, occurred in the two patients. When the nasal pressure was raised to 10 cm H2O, normal levels of tidal airflow occurred, and obstructive apneas were eliminated. These findings indicate that sleep apnea was caused by laryngeal airflow obstruction that resulted from elevations in the collapsibility of the larynx. The response to nasal continuous positive airway pressure suggested that laryngeal sleep apnea was similar to pharyngeal sleep apnea in pathophysiologic characteristic and response to treatment.

Starches of varied digestibilities differentially modify intestinal function in rats

Starches of different digestibilities may enter the colon to different extents and alter colonic function. Male Fischer 344 rats were fed diets containing 25% cooked potato starch, arrowroot starch, high amylose cornstarch or raw potato starch for 6 wk. Fecal weight, transit time, colonic thymidine kinase activity (a marker for cell proliferation), and weight, starch content and pH of the cecum and proximal and distal colon were measured. Raw potato starch was much less completely digested than high amylose cornstarch, resulting in a 32-fold greater amount of undigested starch entering the cecum in the raw potato starch group. Both the high amylose cornstarch and raw potato starch diets significantly enhanced fecal weight and produced large intestinal hypertrophy, effects that were greatest in the raw potato starch group. Raw potato starch feeding was associated with the highest level of thymidine kinase activity, although the differences in thymidine kinase activity among the four groups were not significant. This diet also produced a 50% longer transit time. Entry of a large amount of raw potato starch into the colon resulted in greater luminal acidity, greater luminal bulk and slower transit. A much smaller amount of starch entered the colon in the high amylose cornstarch group and resulted in fecal bulking but no alteration in transit.

Suppression of estrogen-regulated extracellular tissue plasminogen activator activity of MCF-7 cells by 2,3,7,8-tetrachlorodibenzo-p-dioxin

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) suppresses the estrogen enhancement of tissue plasminogen activator (t-PA) by MCF-7 breast cancer cells. 17 beta-estradiol treatment of MCF-7 cells was previously shown to enhance t-PA secretion in a receptor-mediated process dependent on RNA and protein synthesis. The current studies demonstrate that treatment with TCDD, at a concentration as low as 10(-11) M, reduces the 17 beta-estradiol-induced enhancement of t-PA secretion in these cells. Treatment of MCF-7 cells with TCDD alone does not alter t-PA activity nor was inhibition of t-PA activity observed when TCDD was added directly to the enzyme assay. Kinetic studies and the lack of inhibition following in vitro mixing of conditioned media from TCDD-treated and control 17 beta-estradiol stimulated MCF-7 cells argue against TCDD induction of a plasminogen activator inhibitor. The related polychlorinated dibenzofuran, 2,3,7,8,-tetrachlorodibenzofuran, while also active, is less potent that TCDD. Other polychlorinated dibenzodioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls do not suppress 17 beta-estradiol induction of t-PA over the concentrations tested. These results are in agreement with the structure-activity relationships established using these compounds in other assay systems. Treatment with TCDD does not alter the number or affinity of 17 beta-estradiol receptors of MCF-7 cells. TCDD treatment does not suppress constitutive t-PA activity in the estrogen independent breast cancer line MDA-MB-231 nor the t-PA induced by 12-O-tetradecanoylphorbol-13-acetate in HeLa cells. These effects suggest that TCDD is not acting directly on expression of the t-PA genome. Induction of aryl hydrocarbon hydroxylase by TCDD, a cytochrome P-450 regulated metabolic enzyme for which TCDD is the most potent known inducer, was observed in MCF-7 cells but not in MDA-MB-231 or HeLa cells. A plausible mechanism for the antiestrogenic activity of TCDD is based on the metabolic conversion of 17 beta-estradiol to less active derivatives by TCDD induced cytochrome P-450 metabolic enzymes.