Biomedical subjects

David L Steward

Publications and source records attributed to David L Steward.

26 records · Page 2Linked to original sources

PubMed2004

Effectiveness of multilevel (tongue and palate) radiofrequency tissue ablation for patients with obstructive sleep apnea syndrome.

OBJECTIVES: The primary objective is to determine the effectiveness of multilevel (tongue base and palate) temperature controlled radiofrequency tissue ablation (TCRFTA) for patients with obstructive sleep apnea syndrome (OSAS). The secondary objective is to compare multilevel TCRFTA to nasal continuous positive airway pressure (CPAP). STUDY DESIGN AND METHODS: The study is a controlled case series of one investigator's experience with multilevel TCRFTA for patients with OSAS. Twenty-two subjects with mild to severe OSAS, without tonsil hypertrophy, completed multilevel TCRFTA (mean 4.8 tongue base and 1.8 palate treatment sessions) and had both pre- and posttreatment polysomnography. Primary outcomes included change from baseline in apnea/hypopnea index (AHI), daytime somnolence, and reaction time testing measured 2 to 3 months after TCRFTA. Secondary outcomes included change in other respiratory parameters, OSAS related quality of life, and upper airway size. Comparison of 18 patients treated with TCRFTA for mild to moderate OSAS (AHI > 5 and < or = 40) is made with 11 matched patients treated with nasal CPAP for mild to moderate OSAS. RESULTS: Multilevel TCRFTA significantly improved AHI (P = .001), apnea index (P = .02), as well as respiratory and total arousal indices (P = .0002 and P = .01). Significant improvement with moderate or large treatment effect sizes were noted for OSAS related quality of life (P = .01) and daytime somnolence (P = .0001), with a trend toward significant improvement in reaction time testing (P = .06), with mean posttreatment normalization of all three outcome measures. Fifty-nine percent of subjects demonstrated at least a 50% reduction in AHI to less than 20. The targeted upper airway, measured in the supine position, demonstrated a trend toward significant improvement in mean cross sectional area (P = .05) and volume (P = .10). Side effects of TCRFTA were infrequent, mild, and self-limited. No significant correlation between pretreatment parameters and outcome improvement was noted. Nasal CPAP resulted in significant improvement in AHI (P = .0004) to near normal levels, with an associated improvement in OSAS related quality of life (P = .02) and a trend toward significant improvement in daytime somnolence (P = .06). Reaction time testing demonstrated no significant improvement (P = .75). No significant differences were seen for change in AHI, OSAS related quality of life, daytime somnolence, or reaction time testing between multilevel TCRFTA and CPAP. CONCLUSION: Multilevel (tongue base and palate) TCRFTA is a low-morbidity, office-based procedure performed with local anesthesia and is an effective treatment option for patients with OSAS. On average, abnormalities in daytime somnolence, quality of life, and reaction time testing demonstrated improvement from baseline and were normalized after treatment. Polysomnographic respiratory parameters also demonstrated significant improvement with multilevel TCRFTA.

Adult↗

PubMed2004

Amiodarone-induced thyrotoxicosis and thyroid cancer: clinical, immunohistochemical, and molecular genetic studies of a case and review of the literature.

Amiodarone-induced thyrotoxicosis (AIT) is a well-known complication of amiodarone treatment found in 3% to 12% of patients. Two types of AIT have been described, each associated with a distinct histologic pattern of thyroid involvement. Type 1, which typically develops in the background of pre-existing thyroid disease, is due to iodine-induced excess thyroid hormone synthesis, whereas type 2 is due to destructive thyroiditis. The prevalence of thyroid cancer in patients with AIT is unknown. We report a case of papillary thyroid carcinoma associated with type 2 AIT.

Amiodarone↗

PubMed2003

The clinical effects of hyaluronic acid ester nasal dressing (Merogel) on intranasal wound healing after functional endoscopic sinus surgery.

OBJECTIVES: We sought to determine the efficacy of MeroGel, an absorbable hyaluronic acid nasal dressing (HA) in reducing synechia after functional endoscopic sinus surgery (FESS) compared with Merocel, a nonabsorbable packing (NAP) requiring removal. METHODS: We conducted a blinded, randomized, controlled trial of 37 patients requiring bilateral FESS for chronic sinusitis. Patients were randomized to placement of HA within the right or left middle meatus and NAP on the other side. Patients were evaluated at 2, 4, 6, and 8 weeks postoperatively. RESULTS: Blinded evaluation revealed 5 patients (14%) with synechia at last follow-up: 3 sides (8%) with HA and 3 (8%) with NAP. Thirteen patients (35%) had synechia at any visit, 10 sides (27%) with HA and 9 (24%) with NAP. Seven patients (19%) required lysis of synechia, 5 sides (14%) with HA and 3 (8%) with NAP. CONCLUSION: We found no statistically significant difference between HA and NAP dressings.

Bandages↗

PubMed2003

A randomized trial of temperature-controlled radiofrequency, continuous positive airway pressure, and placebo for obstructive sleep apnea syndrome.

OBJECTIVE: The study goal was to determine the effectiveness of (1) multilevel temperature-controlled radiofrequency tissue ablation (TCRFTA) or (2) continuous positive airway pressure (CPAP) for the treatment of mild to moderate obstructive sleep apnea syndrome (OSAS). STUDY DESIGN AND METHODS: We conducted a randomized, placebo-controlled, 2-site trial, comparing TCRFTA (n = 30) and CPAP (n = 30) with sham-placebo (n = 30) using intention-to-treat analysis. RESULTS: Compared with pretreatment baseline, TCRFTA improved reaction time, OSAS-specific quality of life (QOL), and subjective sleepiness (all P < 0.05). Compared with sham-placebo, TCRFTA improved QOL, airway volume, apnea index, and respiratory arousal index (all P < 0.05). TCRFTA side effects and complications were mild, temporary, and similar to sham-placebo. CPAP improved QOL and sleepiness compared with baseline and QOL when compared with sham-placebo (all P < 0.05). Significant differences were not seen between TCRFTA and CPAP outcomes. CONCLUSION: TCRFTA and CPAP each improve QOL for mild-moderate OSAS patients. TCRFTA improvements may result from changes in airway volume, apnea index, and respiratory arousal index.

Adolescent↗

PubMed2003

Dietary antioxidant intake in patients at risk for second primary cancer.

OBJECTIVES: To analyze dietary antioxidant intake for head and neck cancer patients at risk for development of second primary cancers. STUDY DESIGN: Prospective observational study. METHODS: Twenty-four patients underwent three random, unscheduled, 24-hour dietary recalls over a 15-day period within 6 to 60 months after successful treatment for stage I or II oral cavity squamous cell carcinoma. RESULTS: The study sample had a lower mean daily dietary intake of fruits and vegetables and antioxidant nutrients, including vitamins A, C, E, and total carotenes than age- and sex-matched historic control subjects (all P <.05 except vitamin A). A positive linear correlation was noted between daily servings of F&V and dietary intake of vitamins A, C, E, and total carotenoids (all P <.05 except vitamin A). Compared to current recommendations, the study sample had lower mean daily dietary intake of vitamins A, C, and E (P =.81,.06, and <.01) and servings of fruits and vegetables (P <.01). When vitamin supplements were included in the analysis, mean daily intake exceeded recommended dietary allowance (RDA) for vitamins A, C, and E (all P <.05). CONCLUSION: This study suggests that patients treated for early-stage oral cavity carcinoma, at risk for second primary cancers, have a statistically significant deficiency in dietary (food) sources of antioxidant nutrients when compared with both historic control subjects and current recommendations. Vitamin supplementation significantly exceeded current RDAs. Because increased fruit and vegetable intake, but not vitamin supplementation exceeding RDA, is associated with reduced cancer risk, physicians may consider recommending at least five daily servings of fruits and vegetables as an alternative to vitamin supplementation.

Aged↗

PubMed2002

Transpetrosal surgery techniques.

The complex anatomy of the region necessitates thorough study if transpetrosal surgery is to be performed with minimal patient morbidity. Furthermore, by using flexibility, a team approach, and preoperative planning, the surgical procedure can be tailored to the patient, rather than fitting the patient to a fixed surgical procedure. Finally, minimizing patient morbidity is equivalent to preservation of cranial nerves and crucial vascular structures. Close surveillance and judicious postoperative radiotherapy following cytoreductive surgery provides improved patient outcomes compared with radical surgery that results in cranial nerve deficits.

Humans↗

PubMed2002

Meningioma involving Meckel's cave: transpetrosal surgical anatomy and clinical considerations.

Meningiomas originating in Meckel's cave (MC) are uncommon lesions that represent 1% of all intracranial meningiomas. Innovations in skull base surgery have enabled resection of these lesions with less morbidity, but require an intimate knowledge of both lesional pathology and regional microneuroanatomy. To review the surgical and clinical considerations involved in the management of MC meningiomas, we retrospectively reviewed data from patients who underwent transpetrosal resection of primary MC meningiomas between 1984 and 1998. Of 146 patients who underwent transpetrosal removal of meningiomas, 7 were believed to have tumors originating in MC. All 7 patients presented with trigeminal dysfunction, facial pain, and/or headache. Complete tumor removal was achieved in 5 of the 7 patients. Facial hypoesthesia or anesthesia, paralysis of cranial nerve VI, and ophthalmoplegia were among the postoperative complications encountered. Meningiomas of MC represent treatable lesions whose diagnosis requires prompt imaging of patients with trigeminal dysfunction and symptoms of facial pain and headache.

Adult↗

PubMedDate not supplied

Acoustic rhinometry predicts tolerance of nasal continuous positive airway pressure: a pilot study.

BACKGROUND: Nasal continuous positive airway pressure (nCPAP) is usually the first-line intervention for obstructive sleep apnea, but up to 50% of patients are unable to tolerate therapy because of discomfort-usually nasal complaints. No factors have been definitively correlated with nCPAP tolerance, although nasal cross-sectional area has been correlated with the level of CPAP pressure, and nasal surgery improves nCPAP compliance. This study examined the relationship between nasal cross-sectional area and nCPAP tolerance. METHODS: We performed acoustic rhinometry on 34 obstructive sleep apnea patients at the time of the initial sleep study. Patients titrated to nCPAP were interviewed 18 months after starting therapy to determine CPAP tolerance. Demographic, polysomnographic, and nasal cross-sectional area data were compared between CPAP-tolerant and -intolerant patients. RESULTS: Between 13 tolerant and 12 intolerant patients, there were no significant differences in age, gender, body mass index, CPAP level, respiratory disturbance index, or subjective nasal obstruction. Cross-sectional area at the inferior turbinate differed significantly between the two groups (p = 0.03). This remained significant after multivariate analysis for possibly confounding variables. A cross-sectional area cutoff of 0.6 cm2 at the head of the inferior turbinate carried a sensitivity of 75% and specificity of 77% for CPAP intolerance in this patient group. CONCLUSION: Nasal airway obstruction correlated with CPAP tolerance, supporting an important role for the nose in CPAP, and providing a physiological basis for improved CPAP compliance after nasal surgery. Objective nasal evaluation, but not the subjective report of nasal obstruction, may be helpful in the management of these patients.

Adult↗