Cochlear obliteration following a translabyrinthine approach and its implications in cochlear implantation

The most frequent sequelae following a translabyrinthine approach for vestibular schwannoma resection is complete hearing loss on the affected side. Such patients could benefit from a cochlear implant, provided that two essential requisites are met before surgery: a preserved cochlear nerve and a patent cochlea to accommodate the electrode array. The goal of our study is to determine the prevalence and extent of cochlear ossification following a translabyrinthine approach. Postoperative MRI of 41 patients were retrospectively reviewed. Patients were classified according to the degree of cochlear obliteration into three groups (patent cochlea, partially obliterated cochlea and totally obliterated cochlea). The interval between surgery and the first MRI was studied as well as its relationship with the rate of cochlear ossification. At first postoperative MRI (mean interval of 20 months), 78% of patients showed some degree of cochlear ossification. Differences were found in the time interval between surgery and first MRI for each group, showing a smaller interval of time the patent cochlea group (p > 0.05). When MRI was performed before the first year after surgery, a larger rate of patent cochlea was found (p > 0.05). The present study suggests that cochlear ossification is a time-depending process, whose grounds are still to be defined.

[Evolution over time in over perceivers of dyspnea in asthma]

OBJECTIVE

In previous studies we identified a subgroup of patients whose perception of breathlessness was exaggerated during acute bronchoconstriction and who were termed "over perceivers" or "hyperperceivers". In this study we aimed to determine whether such over perception is sporadic or stable over time. We also examined whether there is an association between over perception of dyspnea and hyperventilation syndrome.

PATIENTS AND METHODS

The subjects were 22 stable asthmatics (11 men, 11 women) who had been over perceivers of dyspnea in a study 9 years earlier. After a medical history was taken, a patient performed forced spirometry and a severity classification was made according to the criteria of the Global Initiative for Asthma (GINA). A bronchial histamine challenge was then administered to measure dose-related perception of dyspnea on a Borg scale, according to a procedure that was similar to the one used 9 years earlier by the same investigator. The patients were also asked for a subjective assessment of the severity of their asthma (scale, 0-10) and to respond to items on the Nijmegen hyperventilation questionnaire and the trait form of the State-Trait Anxiety Inventory.

RESULTS

The overall perception of severity of disease, level of anxiety, and perception of dyspnea at rest were lower after 9 years (P<.001). No change was observed in bronchial hyperresponsiveness (dose of inhaled histamine required to provoke a 20% decline in forced expiratory volume in the first second [FEV1]-PD20) or objective parameters of severity (FEV1 and GINA classification). Fourteen asthmatics (64%) were still over perceivers and the other patients had changed: 6 were normal perceivers and 2 were "poor perceivers". Only subjective perception of disease severity improved for the patients who were still over perceivers; the other patients, on the other hand, showed improvements in subjective assessments, objective ones (except PD20), and anxiety. Finally, those who remained over perceivers had higher scores for anxiety (24 vs 15; P<.05) and hyperventilation (18 vs 13; P= not significant).

CONCLUSIONS

Most over perceivers of dyspnea remain so over the years and this trait is related to anxiety. We have been unable to demonstrate an association with hyperventilation syndrome.

[Efficacy of an antibacterial filter for preventing contamination of respiratory function diagnostic equipment]

OBJECTIVES

Devices to assess lung function are a potential source of nosocomial infection. Our aims in this study were: 1) to determine the efficacy of an antimicrobial filter to prevent contamination of a multifunctional device; 2) to assess the ability of the filter to prevent cross contamination of individuals being tested; and 3) to evaluate the efficacy of the recommendations of the Spanish Society of Respiratory Diseases and Thoracic Surgery for disinfecting lung function equipment.

DESIGN

In this prospective, randomized study in two phases we used filters in phase 1 but not in phase 2. A pharyngeal swab culture was started within 7 days of a patient's lung function test. Swab samples for culturing were taken from three different places in the equipment at the beginning and end of each working day.

PATIENTS

Sixty-five patients (31 in phase 1 and 34 in phase 2) were studied. Thirty-two (49.2%) were men and the mean age was 49.4 15.7 years.

RESULTS

Significantly less equipment contamination was found in phase 1 (4.2%) than in phase 2 (21%). We detected no cases of cross contamination using the criteria in this study. No cultures from any of the samples taken before exploration were positive.

CONCLUSIONS

a) The antimicrobial filter used is effective for preventing the contamination of lung function testing equipment, b) throughout both phases of the study, we observed no cross contamination of patients tested, such that we cannot conclude that the antimicrobial filter is effective for preventing possible nosocomial infections, c) the recommendations of SEPAR for disinfecting lung function equipment are effective.