[Recent developments in the diagnosis and treatment of obstructive sleep apnea]. / Aktuelle Aspekte in der Diagnostik und Therapie der obstruktiven Schlafapnoe.

Over the past years, the diagnostic tools and therapeutic approaches for obstructive sleep apnea (OSA) have further evolved. Based on a review of current literature and the personal experiences of the authors, the most relevant developments are summarized in this article and discussed with regard to their impact on the clinical management of this disease. In the third edition of the "International Classification of Sleep Disorders", the classification of sleep-disordered breathing was modified. Notably, additional clinical criteria for the diagnosis of OSA were established and out-of-center sleep testing was introduced as an alternative to polysomnography. Recent technical advancement of new diagnostic tools (e.g., peripheral arterial tonometry and pulse wave analysis) has further expanded the diagnostic possibilities. Drug-induced sleep endoscopy enables reliable assessment of the level and degree of upper airway obstruction. Whether this gain in diagnostic information leads to an improvement in surgical outcome is, however, still under discussion. The relevance of positional OSA has received increasing attention-the proportion of patients in whom sleeping position significantly impacts disease is reported to be above 50%. For these patients, the introduction of the sleep position trainer has made a new therapeutic option available. Furthermore, hypoglossal nerve stimulation (upper airway stimulation) has substantially expanded the surgical spectrum of OSA treatment. For the established surgical treatment options, randomized trials with superior methodology have been published, particularly for bimaxillary advancement and tonsillectomy with uvulopalatopharyngoplasty. These developments are of particular interest for the otolaryngologist and will influence daily practice.

[Submental transcutaneous electrical stimulation for obstructive sleep apnea]. / Transkutane, submentale Elektrostimulationstherapie bei obstruktiver Schlafapnoe.

BACKGROUND: Transcutaneous electrical stimulation while asleep has been used to treat obstructive sleep apnea (OSA), although without convincing results. Modern strategies consist of electrical muscle training for a number of weeks during wakefulness rather than stimulation during sleep. OBJECTIVE: The purpose of this study was to assess the practicability, safety, and efficacy of a new device, SilentOne (Imperpuls, Chemnitz, Germany). PATIENTS AND METHODS: Fifteen patients with various degrees of OSA used transcutaneous submental electrical stimulation therapy for 4-5 weeks every day, day and night. A patient's diary recorded practicability and potential adverse events. Respiratory parameters were recorded by fully attended polysomnography in the sleep lab. Daytime sleepiness and snoring were assessed by questionnaires. RESULTS: The apnea-hypopnea-index decreased from 29.2 before to 21.2 after therapy (P<0.05). Daytime sleepiness improved significantly (P<0.01) as did snoring (P<0.005). CONCLUSIONS. Transcutaneous electrical stimulation therapy using SilentOne proved to be safe, easy to use, and potent. However, therapy showed a limited cure rate.

[Cluster-immunotherapy in seasonal allergic rhinitis: safety aspects of induction therapy with depot allergoids (Purethal)]. / Cluster-Immuntherapie bei saisonaler allergischer Rhinitis: Erfahrungen zur Sicherheit einer Initialtherapie mit Depot-Allergoiden (Purethal).

BACKGROUND: Specific immunotherapy (SIT) represents the only specific treatment that can be offered to allergic patients apart from allergen avoidance. SIT has been widely used in pollen allergic rhinitis. Clinical efficacy has been demonstrated in several controlled clinical trials and depends on the specific allergen the individual patient is sensitive to, the quality and total amount of allergen applied, and the SIT schedule. In classic SIT, gradually increasing dosages of the allergen extract are injected subcutaneously. Several dosage schedules for subcutaneous SIT can be applied. In Cluster-SIT, 2 - 3 injections per day of treatment are given once a week during induction treatment. PATIENTS: In this study, we investigated 64 patients (33 female, 31 male) from 18 to 54 years (26.9 +/- 5.1 years) in terms of side-effects of Cluster-SIT during induction treatment. RESULTS: The total amount of enlarged local reactions (> grade 1) was n = 77 or 15.2 % of all injections. Of these, 68 (88 %) were classified as immediate reactions, 8 (11 %) were late phase reactions and 1 (1 %) was immediate as well as late phase reaction. Of all enlarged local reactions, 48 (62 %) were grade 1 reactions, 13 (17 %) were grade 2 reactions, 13 (17 %) were grade 3 reactions and 1 (1 %) was a grade 4 reaction. The total amount of systemic reactions was n = 22 or 4.3 % of all injections. Of these, 19 (86 %) were classified as immediate reactions, 3 (14 %) were delayed reactions. Of all systemic reactions, 18 (82 %) were grade 1 reactions and 4 (18 %) grade 2 reactions. Grade 3 or grade 4 reactions did not occur. There were no differences in gender or age regarding the occurrence of side effects (all p > 0.05). CONCLUSIONS: Frequency and severity of adverse side effects in Cluster-SIT correspond to those in other dosage schedules. On behalf of security aspects, Cluster-SIT could become an interesting alternative dosage schedule for dose increase during SIT. Furthermore, in Cluster-SIT with allergoids, induction treatment can be carried out in two treatment days of approximately 2.5 hours each.

Cytoprotection against thermal injury: evaluation of herbimycin A by cell viability and cDNA arrays.

Herbimycin A (HA), a known inducer of the heat shock response, was investigated for its ability to increase survival of a human cell line following thermal injury. Its effect on transcriptional activity was also assessed with cDNA arrays to provide new targets for cytoprotection. Pretreatment with at least 0.75 microg/ml HA significantly increased the fraction of cells surviving thermal injury by up to 50% (based on 8s exposure) compared to untreated controls. HA also significantly induced transcription of mRNA for HSP90 and HSP70, and protein production for HSP40 and HSP70. Gene expression profiling demonstrated that the most highly elevated genes included growth factors and transcription factors, while prominently suppressed genes included transcription factors and kinases. These results suggest that cytoprotection may be due to the contribution of the products of a significant number of genes in addition to the classic stress response genes, suggesting that modulation of these genes might induce thermotolerance and amelioration of thermal injury.

[Tongue base reduction with radiofrequency energy in sleep apnea]. / Die Zungengrundreduktion mit Radiofrequenzenergie bei schlafbezogenen Atmungsstörungen. Postoperative Morbidität und Komplikationen.

BACKGROUND AND OBJECTIVE: Tongue base reduction with temperature-controlled radiofrequency for the treatment of obstructive sleep apnea syndrome is a minimally invasive technique. Repeated application leads to a progressive shrinking of the tissue. PATIENTS AND METHODS: In our study, we summarize the experiences gained from 100 tongue base reductions and compare them with the pilot study that was recently published. An intensified treatment scheme was used with higher amounts of energy applied per treatment session. Visual analogue scales were used for the assessment of postoperative pain and functional parameters. Regular follow-up visits were scheduled to evaluate postoperative complications. RESULTS: Postoperative pain was mostly mild or moderate. Paraoperative complications were not observed. The overall rate for postoperative complications was 8%, with 2% mild and 5% moderate complications. One severe complication--a tongue base abscedation--was observed. Using para- and postoperative antibiotic prophylaxis reduced the rate of complications. Functional parameters such as taste or swallowing were not affected. CONCLUSIONS: Our results underline the safety of the procedure and demonstrate the minimal para- and postoperative morbidity. The increased amount of energy applied per session has not led to an increase in postoperative morbidity.

Effects of high peak power microwaves on the retina of the rhesus monkey.

We studied the retinal effects of 1.25 GHz high peak power microwaves in Rhesus monkeys. Preexposure fundus photographs, retinal angiograms, and electroretinograms (ERG) were obtained to screen for normal ocular structure and function and, after exposure, as endpoints of the study. Histopathology of the retina was an additional endpoint. Seventeen monkeys were randomly assigned to receive sham exposure or pulsed microwave exposures. Microwaves were delivered anteriorly to the face at 0, 4.3, 8.4, or 20.2 W/kg spatially and temporally averaged retinal specific absorption rates (R-SAR). The pulse characteristics were 1.04 MW ( approximately 1.30 MW/kg temporal peak R-SAR), 5.59 micros pulse length at 0, 0.59, 1. 18, and 2.79 Hz pulse repetition rates. Exposure was 4 h per day and 3 days per week for 3 weeks, for a total of nine exposures. The preexposure and postexposure fundus pictures and angiograms were all within normal limits. The response of cone photoreceptors to light flash was enhanced in monkeys exposed at 8.4 or 20.2 W/kg R-SAR, but not in monkeys exposed at 4.3 W/kg R-SAR. Scotopic (rod) response, maximum (combined cone and rod) response, and Naka-Rushton R(max) and log K of scotopic b-waves were all within normal range. Retinal histopathology revealed the presence of enhanced glycogen storage in photoreceptors among sham (2/5), 8.4 W/kg (3/3), and 20.2 W/kg (2/5) exposed monkeys, while enhanced glycogen storage was not observed in the 4.3 W/kg (0/4) exposed group. Supranormal cone photoreceptor b-wave was R-SAR dependent and may be an early indicator of mild injury. However no evidence of degenerative changes and ERG depression was seen. We concluded that retinal injury is very unlikely at 4 W/kg. Functional changes that occur at higher R-SAR are probably reversible since we saw no evidence of histopathologic correlation with ERG changes. Bioelectromagnetics 21:439-454, 2000. Published 2000 Wiley-Liss, Inc.

Wound healing after laser injury to skin--the effect of occlusion and vitamin E.

The skin of Yorkshire pigs was irradiated with various doses of argon and copper-vapor laser and evaluated for effects on healing time of pretreatment with topical or intramuscular vitamin E or the Op-Site wound dressing. Incident irradiance for both lasers was between 3.5 and 4.5 W/cm2 for a 10-14-mm beam diameter with a nearly uniform intensity profile. Minimal erythemic dose for the copper-vapor laser was 35 +/- 2 J/cm2 (10 s exposure) and 22.4 +/- 0.1 J/cm2 (6-s exposure) for the argon laser. Three dose levels were administered: a low dose causing light erythema, an intermediate dose, and a high dose causing dermal stasis. The radiant exposures for low, intermediate, and high doses were 35, 70, and 138 J/cm2 for the copper-vapor laser and 22.4, 55, and 129 J/cm2 for the argon laser. Exposure to argon and copper-vapor lasers generally caused wounds with similar healing times. Healing time was significantly decreased for wounds caused by intermediate exposure of the copper-vapor laser and either pretreated with vitamin E or treated with the wound dressing. Healing times for corresponding argon-laser exposure were significantly decreased with pretreatment of intramuscular vitamin E only or after treatment with the wound dressing. These findings may be valuable in selecting treatment for accidental laser skin injuries in man.

Laser induced thermal injury of rabbit cornea and treatment with anti-inflammatory agents.

A moderately severe thermal injury of the central cornea of 48 Dutch-belted rabbit eyes was produced with a carbon (CO2) laser. The lesions were photographed with a slit lamp (SL) camera immediately following the injury and at 1, 2, 4, 7, 14, 21, 30 and 60 days after the exposure. Lesion size, opaqueness, and depth were graded clinically by SL biomicroscopy at the same intervals. No significant differences were found (p less than or equal to 0.05) between groups of eyes treated with flurbiprofen (0.03%), prednisolone acetate (1%), and vehicle control four-times-a-day for three weeks following injury. Additionally, eyes were studied histopathologically at 3 and 60 days following injury by light and transmission electron microscopy, and clinically at 30 and 60 days by endothelial specular microscopy. Important clinical and histopathological findings included coagulative necrosis of the corneal epithelium, epithelial sloughing, fusion of stromal collagen, stromal edema and inflammatory cell infiltration, stromal scar formation, corneal thinning, endothelial hyperplasia and metaplasia, fibrinous anterior chamber reaction with hypopyon, and retrocorneal fibrous membrane formation.