Kees Graamans

Physiologic and hypertonic saline solutions impair ciliary activity in vitro

Objective/Hypothesis: Physiologic saline (NaCl 0.9%) is commonly used in treating acute and chronic rhinosinusitis. Moreover, physiologic saline is used as a control medium, vehicle, or solvent in studies on ciliary beat frequency (CBF). Hypertonic saline (NaCl 7% and 14.4%) has been applied in attempts to enhance mucociliary transport in patients with cystic fibrosis or asthma and in healthy subjects. Therefore the objective of this study is to document in vitro effects of saline solutions in different concentrations on CBF. Study Design: Experimental, in vitro. Methods: The effects on CBF of cryopreserved mucosa of the sphenoidal sinus was measured by a photoelectrical method. Initial frequencies, measured in Locke‐Ringers solution (LR), were compared with CBF after exposure to NaCl in concentrations of 0.9%, 7.0%, and 14.4% (w/v). Results: NaCl 0.9% has a moderately negative effect on CBF. The 7% solution leads to a complete ciliostasis within 5 minutes, although this effect turns out to be reversible after rinsing with LR. A hypertonic solution of 14.4% has an irreversible ciliostatic effect. Conclusion: LR is an isotonic solution that has no effect on CBF. Therefore it is probable that this solution is more appropriate than saline for nasal irrigation and nebulization or antral lavage. Moreover, the results of this study suggest that mucolytic effects induced by hyperosmolarity should be attained preferably with hypertonic saline 7% in patients with cystic fibrosis or asthma. At this concentration, the ciliostatic effect is reversible, whereas irreversible changes are to be expected at higher concentrations.

Correlation between nasal ciliary beat frequency and mucus transport rate in volunteers

The correlation between mucus transport time (MTT) and nasal ciliary beat frequency (CBF) in human volunteers was investigated. Mucus transport was measured with the indigo carmine/saccharin sodium test. The test can be performed easily, with no need for sophisticated equipment. CBF was measured photometrically in biopsies from the ciliated epithelium of the nose.

Gamma knife radiosurgery for vestibular schwannomas: Results of hearing preservation in relation to the cochlear radiation dose

This study was designed to evaluate hearing preservation after gamma knife radiosurgery (GKRS) and to determine the relation between hearing preservation and cochlear radiation dose in patients with a sporadic vestibular schwannoma (VS).

Nasal Mucociliary Transport: New Evidence for a Key Role of Ciliary Beat Frequency †

Objectives/Hypothesis Mucociliary transport is an important defense mechanism of the respiratory tract. Nonetheless, the factors determining mucociliary transport are only partially understood. Ciliary beat frequency is assumed to be one of the main parameters, although the experimental evidence remains inconclusive.

Advances in Understanding the Pathogenesis of Pneumococcal Otitis Media

In this review, a state of the art on otitis media research is provided with emphasis on the role of Streptococcus pneumoniae in the pathogenesis of this disease. Articles have been selected by MEDLINE search supplemented with a manual crosscheck of bibliographies. Pathogenic mechanisms in middle ear and eustachian tube are described. Furthermore, pneumococcal characteristics and pneumococcus–host interactions are highlighted as well as the possible role of biofilms in persistence or recurrence of otitis media. Because of the availability of new techniques, an increasing number of pneumococcal features contributing in the pathogenesis of otitis media are identified and in-depth knowledge of pneumococcus–host interactions has been gained. The present advances in research on otitis media open up new perspectives for therapeutic or preventive strategies.

Microbial profiling does not differentiate between childhood recurrent acute otitis media and chronic otitis media with effusion

Abstract Objectives Otitis media (OM) is one of the most frequent diseases of childhood, with a minority of children suffering from recurrent acute otitis media (rAOM) or chronic otitis media with effusion (COME), both of which are associated with significant morbidity. We investigated whether the microbiological profiling could be used to differentiate between these two conditions. Methods Children up to five years of age, with rAOM (n =45) or COME (n =129) and scheduled for tympanostomy tube insertion were enrolled in a prospective study between 2008 and 2009. Middle ear fluids (n =119) and nasopharyngeal samples (n =173) were collected during surgery for bacterial culture and PCR analysis to identify Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis, and to detect 15 distinct respiratory viruses. Results The occurrence of bacterial and viral pathogens in middle ear fluids did not significantly differ between patients suffering from rAOM and COME. In both patient cohorts, H. influenzae and rhinovirus were the predominant pathogens in the middle ear and nasopharynx. Nasopharyngeal carriage with two or three bacterial pathogens was associated with the presence of bacteria in middle ear fluid (P =0.04). The great majority of the bacteria isolated from middle ear fluid were genetically identical to nasopharyngeal isolates from the same patient. Conclusions Based on these results, we propose that the common perception that rAOM is associated with recurrent episodes of microbiologically mediated AOM, whereas COME is generally a sterile inflammation, should be reconsidered.

Follow-up after gamma knife radiosurgery for vestibular schwannomas: volumetric and axial control rates

A prospective long‐term follow‐up study was conducted to evaluate the results of gamma knife radiosurgery (GKRS) for vestibular schwannoma (VS) patients. Both axial and volumetric measurements are used to determine tumor size during follow‐up.

Testing ciliary activity in patients with chronic and recurrent infections of the upper airways: Experiences in 68 cases

The clinical use of various tests of ciliary activity is uncertain and the purpose of this study is to assess the practical significance of the most current methods. Therefore, biopsy specimens of the nasal mucosa were investigated by means of phase contrast microscopy in 68 patients with chronic and recurrent infections of the upper airways. In 19 cases an absent or extremely weak ciliary activity could be demonstrated. Ultrastructurally, a characteristic pattern of defective dynein arms as observed in primary ciliary dyskinesia, was evident in only 3 out of these 19 patients. Measurements of the mucociliary transport velocity by means of intranasal Tc 99m labeled particles appeared to be unreliable in cases of severe nasal obstruction.

Predictors of future growth of sporadic vestibular schwannomas obtained by history and radiologic assessment of the tumor

Management of a sporadic vestibular schwannoma (VS) is still a subject of controversy, mainly due to distinct and unpredictable growth patterns. To embark on an appropriate therapy it is necessary to dispose of a reliable prediction about tumor progression. This study aims to design a risk profile with predictors for VS growth. A total of 234 VS patients who were managed conservatively were included. Data concerning (duration of) symptoms and localization of VS were analyzed with Cox proportional hazards regression models. Predictors for growth are unsteadiness/vertigo, no sudden onset of hearing loss and short duration of hearing loss. High-risk patients have (1) VS with an extrameatal localization, short duration of hearing loss and at least one of the two other predictors (unsteadiness/vertigo or no sudden sensorineural hearing loss) or (2) VS with an intrameatal localization and all three other predictors. Low-risk patients have (1) VS with an extrameatal component and no other predictor or (2) VS with an intrameatal localization and at most one other predictor. High-risk patients have a risk of growth of 36.9% in the first year and 64.6% in the second year. For patients with a low risk this is 2.5 and 12.7%, respectively. Simple data gathered at the moment of diagnosis may provide useful information since they may lead to a risk profile for growth.

Inflammation in the middle ear of children with recurrent or chronic otitis media is associated with bacterial load.

Background: Viral upper respiratory tract infections have been described as an important factor in the development of otitis media (OM), although it is unclear whether they facilitate bacterial OM or can directly cause OM. To clarify the role of viral infections in OM, we compared the relative contribution of viruses and bacteria with the induction of inflammatory cytokine responses in the middle ear of children suffering from OM. Methods: Children up to 5 years of age, with recurrent or chronic episodes of OM and scheduled for ventilation tube insertion were enrolled in a prospective study. Middle ear fluids (n = 116) were collected during surgery, and quantitative polymerase chain reaction was performed to detect bacterial and viral otopathogens, that is, Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and 15 respiratory viruses. Finally, concentrations of the inflammatory mediators interleukin (IL)-1&bgr;, IL-6, IL-8, IL-10, IL-17a and tumor necrosis factor-&agr; were determined. Results: Middle ear fluids were clustered into 4 groups, based on the detection of viruses (28%), bacteria (27%), both bacteria and viruses (27%) or no otopathogens (19%). Bacterial detection was associated with significantly elevated concentrations of cytokines compared with middle ear fluids without bacteria (P < 0.001 for all cytokines tested) in a bacterial load-dependent and species-dependent manner. In contrast, the presence of viruses was not associated with changes in cytokine values, and no synergistic effect between viral-bacterial coinfections was observed. Conclusions: The presence of bacteria, but not viruses, is associated with an increased inflammatory response in the middle ear of children with recurrent or chronic OM.