Biomedical subjects

Thomas Verse

Publications and source records attributed to Thomas Verse.

27 records · Page 2Linked to original sources

PubMed2003

Impact of impaired nasal breathing on sleep-disordered breathing.

OBJECTIVE: The role of the nose and its importance in the development and severity of sleep-disordered breathing (SDB) is still a matter of discussion. In the first part of this study, often-controversial data and theories about the nose are reviewed concerning its influence on the pathophysiology of SDB and to interpret certain clinical findings connected with impaired nasal breathing. In the second part, the effectiveness of some nonsurgical and surgical therapies is evaluated. METHOD: A worldwide literature research (Medline) was the basis for this review. RESULTS: The study of the literature on nasal resistance and clinical findings about the effects of incomplete or complete nasal blockage, particularly in comparison of healthy persons and persons with SDB, allows the assumption of the existence of two different groups of responders: a larger group where the importance of the nose for SDB is negligible and a smaller group where the influence of the nose on SDB is crucial. The same seems to hold true for the responses to nonsurgical and surgical treatments with only a few surgical results available in the literature. While the success rate of nasal surgery for patients with obstructive sleep apnea, for instance, seems to be less than 20%, the normalization of nasal resistance often leads to a positive impact on the well-being and the sleep quality of these patients. However, because criteria to identify responders are lacking, the prediction of success of any treatment for the individual with SDB is not possible.

Anti-Inflammatory Agents↗

PubMed2003

Complications of temperature-controlled radiofrequency volumetric tissue reduction for sleep-disordered breathing.

OBJECTIVE: Temperature-controlled radiofrequency volumetric tissue reduction (RFVTR) is a minimally invasive technique used in the treatment of the tongue base, soft palate and turbinates. Complications seem to be rare, but the scope of previous studies was often limited by the small number of patients included. The aim of this study was to evaluate postoperative complications in a large series of patients. MATERIAL AND METHODS: In this retrospective study, temperature-controlled radiofrequency procedures (Somnoplasty) performed between May 1998 and March 2002 were considered. The charts of the patients were analyzed with regard to intra- or postoperative complications. RESULTS: In total, 322 patients received 497 treatment sessions; 239 of these treatments were isolated and the remaining 258 were combined procedures. Mean follow-up was 122.8 +/- 145.5 days. Concerning radiofrequency surgery, nine postoperative complications were observed (2.0%) as follows: ulcerations of the tongue base or soft palate; dysphagia necessitating hospital admission; temporary palsy of the hypoglossal nerve; and an abscess of the base of the tongue. CONCLUSIONS: Complications occurring after RFVTR are infrequent and mostly mild. Overall, temperature-controlled RFVTR is a safe procedure when used both in isolation and as part of a combined approach.

Catheter Ablation↗

PubMed2003

Lesion formation in radiofrequency surgery of the tongue base.

OBJECTIVES: Temperature controlled radiofrequency volumetric tissue reduction (RFVTR) of the tongue base is a minimally invasive technique for the treatment of obstructive sleep apnea. But despite its widespread use, little is yet known about in vivo effects in humans. Such knowledge would be essential for evidence-based criteria in the selection of energy application. METHODS: In a preparatory in vitro study, porcine tongues were preserved in growing medium. Lesions with different amounts of energy were applied, and maximum diameters were assessed. In the in vivo study, 11 patients were treated with RFVTR at the tongue base by employing different energy levels (800, 600, 400, or 200 J) on two application sites. Magnetic resonance imagery scans were performed 4 to 6, 8 to 10, and 24 hours after surgery. An inversion recovery technique was used to visualize the lesions. RESULTS: RFVTR created lesions at the porcine tongue from 50 J and higher. Maximum lesion sizes were achieved with 400 J. In vivo, all the lesions were clearly visible in the postoperative scans. Lesion size increased with the amount of energy applied. Maximum diameters were created from 600 J and higher. Higher amounts of energy only resulted in a slight increase in lesion length. CONCLUSIONS: The application of 600 J at 85 degrees C leads to optimal lesion sizes. Higher amounts of energy will not lead to a relevant increase in tissue necrosis. With regard to the time needed for application, 600 J appears to be the ideal adjustment for energy delivery in the treatment of the human tongue.

Airway Obstruction↗

PubMed2002

Upper airway epithelial structural changes in obstructive sleep-disordered breathing.

The etiology of upper airway collapsibility in patients with snoring and obstructive sleep apnea (OSA) remains unclear. Structural mucosal changes could be contributory factors. The objective of this study was to determine whether pathologic changes in the epithelium or the epithelial-connective tissue interface are present in patients with snoring and/or OSA by means of scanning electron microscopy and immunohistochemistry. Uvulae were obtained by uvulopalatopharyngoplasty from three patients with habitual snoring and nine patients with mild to severe OSA, as well as by dissection from 43 nonsnoring body donors. Scanning electron microscopy revealed structural changes in the epithelial-connective tissue boundary that significantly differed from age-related changes in the control subjects. The immunohistochemical staining with antibodies against epithelial cytokeratins showed differences in the expression pattern of cytokeratin 13 between patients and control subjects. No differences were found in the distribution pattern of laminin. Analysis of defense cells revealed a significant diffuse infiltration of leukocytes, mainly T cells, inside the lamina propria of the patient group, which was not observed in the control group. In conclusion, these results support the hypothesis that progressive structural changes in the mucosa caused by the trauma of snoring are a possible contributory factor to upper airway collapsibility.

Adult↗

PubMed2002

Tongue base reduction with temperature-controlled radiofrequency volumetric tissue reduction for treatment of obstructive sleep apnea syndrome.

In recent years a considerable effort has been made to establish the use of different surgical techniques for the treatment of obstructive sleep apnea syndrome (OSAS). Nevertheless, treatment of hypopharyngeal obstruction due to tongue base hypertrophy remains in many ways an unsolved problem. The aim of this study was to evaluate the safety and efficacy of tongue base reduction with temperature-controlled radiofrequency volumetric tissue reduction in the treatment of OSAS. Twenty patients with OSAS and tongue base hypertrophy were treated with radiofrequency tissue ablation. An intensified treatment protocol was used, delivering 2,800 J per treatment session under local anesthesia. Two nights of polysomnography testing were performed before and after treatment. Daytime sleepiness, snoring and postoperative morbidity were assessed using questionnaires. Mean respiratory disturbance index (RDI) was reduced from 32.1 to 24.9/h after a mean of 3.4 treatment sessions. Six patients (33%) were cured after the procedure (reduction in RDI of > or = 50% and a postoperative RDI of < 15/h) and ten (55%) showed an improvement of > 20% in their RDI. Daytime sleepiness and snoring improved significantly. Peri- and postoperative morbidity was low; one severe complication occurred (tongue base abscess). We were able to achieve similar cure and responder rates to those reported in a recently published pilot study but with a reduced number of treatment sessions. We believe that this technique may improve patient acceptance and have beneficial cost implications.

Catheter Ablation↗

PubMed2002

Effect of nasal surgery on sleep-related breathing disorders.

OBJECTIVE/HYPOTHESIS: Single cases of patients who have experienced obstructive sleep apnea (OSA) and who recovered completely after nasal surgery have been described in various studies. The purpose of this study was to evaluate the efficacy of only nasal surgery 1) in a group of patients with obstructive sleep apnea and 2) in simple snorers. STUDY DESIGN: A prospective, controlled study with 26 adult patients who underwent nasal surgery as single treatment of their sleep-related breathing disorders. The cases were evaluated based on the severity level of their preoperative Apnea Hypopnea Index (AHI). MATERIAL AND METHODS: Between August 1996 and July 2000, 26 patients who snored and had impaired nasal breathing underwent attended polysomnography in the sleep laboratory as single treatment nasal surgery was performed. Postoperative polysomnographic findings and complications were reviewed. RESULTS: Nineteen of 26 patients (73.1%) were diagnosed as having OSA. Seven patients were simple snorers with an AHI below 10. The surgical response rates, defined as greater than or equal to 50% reduction in the postoperative AHI and a postoperative AHI of less than 20, was 15.8% in the apneics. For the whole group, the AHI decreased postoperatively from 31.6 to 28.9. However, daytime sleepiness improved significantly and arousals decreased significantly in both apneics and simple snorers after nasal surgery. CONCLUSIONS: We conclude that nasal surgery has a limited efficacy in the treatment of adult patients with sleep apnea. Nevertheless, nasal surgery significantly improves sleep quality and daytime sleepiness independent of the severity of obstructive sleep-related breathing disorders.

Adult↗

PubMed2002

Evaluating the upper airway with standardized magnetic resonance imaging.

OBJECTIVES/HYPOTHESIS: Magnetic resonance imaging (MRI) potentially offers various advantages in assessing the upper airway. The aims of the presented study were 1) to evaluate which anatomical parameters of upper airway soft tissue morphology (distances, areas, volumes) could be defined using MRI scans, 2) to examine the stability or variability of these parameters over time and between different investigators, and 3) to develop a standardized protocol for MRI measurements of the upper airway. STUDY DESIGN: Prospective clinical trial. METHODS: Twenty-four scans were performed on six healthy subjects over a period of 4 weeks. Various parameters such as tongue dimensions, volumes and spaces, posterior airway spaces, and soft palate dimensions were established, and their variation over time between different investigators and with repeated analysis was assessed. RESULTS: All the parameters were of high stability and reproducibility. The time of day had no significant influence on the results. An abbreviated method for the evaluation of the tongue volume was developed. Four-millimeter slices with a conventional MRI scan generate pictures of high quality in a maintainable acquisition time. CONCLUSIONS: We were able to evaluate which anatomical parameters of upper airway could be defined using MRI scans. The variability of these parameters over time and between different investigators was assessed. We developed a standardized protocol for MRI measurements of the upper airway. Standardized protocols are mandatory, and the variability of the measurements must be taken into account if results of different clinical centers must be compared or if changes after therapeutic interventions are to be investigated.

Adult↗

PubMedDate not supplied

Evaluation of protective and therapeutic effects of dexpanthenol on nasal decongestants and preservatives: results of cytotoxic studies in vitro.

BACKGROUND: More than 600 million units of nasal decongestants are sold worldwide annually. The cytotoxic and ciliary toxic potential of decongestants, as well as the preservatives of these products, in particular benzalkonium chloride (BKC), is well established. Recently, a beneficial effect of dexpanthenol on the tolerability of the alpha-sympathomimetic xylometazoline and BKC has been described; however, it was unclear if this effect, resulting in significantly higher cell counts in a cytotoxicity study and an increase in ciliary beat frequency in a ciliary toxicity study was of protective or therapeutic nature. The objective of this study was (a) to evaluate whether dexpanthenol would be a useful additive to nasal decongestants to counter the cytotoxic and ciliary toxic effects of the active ingredient and the preservative and (b) to find out whether this beneficial effect is of protective or therapeutic nature. METHODS: Systematic cytotoxic in vitro tests were performed. After exposure to xylometazoline (0.1%), the effect of dexpanthenol (5%) and BKC (0.01%) was determined by placebo-controlled assessment of cell growth in a human amniotic cell line. RESULTS: Dexpanthenol significantly reduces the toxic effects of xylometazoline regarding cell growth (p < 0.001) when applied in advance. When BKC is eliminated from the nasal sprays, a further significant increase of cell growth was found (p < 0.001). When dexpanthenol is therapeutically applied after xylometazoline, effects on cell growth are only one-half of those of the protective approach. CONCLUSION: The additive application of dexpanthenol (5%) given before nasal decongestants or preserved nasal sprays is able to improve the tolerability of these substances and to counteract the toxic effects.

Administration, Intranasal↗

PubMedDate not supplied

Immunohistochemical analysis of radiation-induced non-healing dermal wounds of the head and neck.

Persistent, poorly healing wounds are a significant clinical problem in patients who have had previous irradiation. The pathology of chronic dermal ulcers is characterised by excessive proteolytic activity which degrades the extracellular matrix (required for cell migration) and growth factors and their receptors. Interestingly, the molecular basis of radiation-induced dermal wounds is poorly understood. The aim of this study was to investigate, by immunohistochemistry, the expression of the endothelial marker vWF, of angiogenic bFGF, VEGF and IL-8, of collagenases MMP-2 and MMP-9 and their inhibitors TIMP-1 and TIMP-2, in tissue samples from radiation-induced chronic dermal wounds and healthy control skin. Performing immunohistochemical detection of microvessels, an equivalent density of microvessels was observed within tissue samples from normal healthy skin and from radiation-induced non-healing cutaneous wounds. Investigation of angiogenic bFGF and VEGF demonstrated a decreased expression of both factors in the radiation-induced dermal wounds. The expression of angiogenic IL-8 was weak in both the healthy skin samples and the radiation-induced wounds. In addition, an increased expression of collagenases MMP-2 and MMP-9 protein within the radiation-induced wounds was demonstrated. While the expression of TIMP-1 showed no difference of expression between normal control skin and tissue samples from radiation-induced wounds, TIMP-2 expression was slightly increased compared to healthy controls. Our data suggest that radiation-induced dermal injuries often fail to heal because of decreased angiogenesis and persistently high concentrations of MMPs with an imbalance of their tissue inhibitors. The basic mechanisms of wound healing in radiation-induced dermal wounds at the molecular level need to be understood further for the development of innovative treatment strategies.

Biomarkers↗