[A new classification code is available in the Danish health-care classification system for patients with symptoms related to chemicals and scents].

From July 2012, a classification code for multiple chemical sensitivity has been available in the Danish healthcare classification system. The overall purpose is to register hospital contacts in Denmark. The diagnostic code is labelled "Symptoms related to chemicals and scents", DR688A1, and classified as a subcategory to "Medically unexplained symptoms", DR688A, which is a specialization of the ICD-10 code "R68.8 Other specified general symptoms and signs". The classification was decided with reference to the present lack of scientific understanding.

[Malfunction of the inner ear is the most frequent cause of dizziness]. / Indre øre-lidelse er den hyppigste årsag til svimmelhed.

Half of all dizziness patients suffer from a malfunction of the inner ear and benign paroxysmal positional vertigo causes 25-30% of these malfunctions. During the latest two decades new vestibular test equipment has been developed and has made it possible to refine the vestibular diagnoses and consequently treat patients more efficiently. This brief overview describes the benefit of Epley's Omniax Chair, video head impulse tests and the Vestibular Autorotation Test. The need for vestibular rehabilitation programmes and for a closer collaboration between physicians and the social authorities is pointed out.

Genetic susceptibility factors for multiple chemical sensitivity revisited.

Multiple chemical sensitivity (MCS) is characterised by adverse effects due to exposure to low levels of chemical substances. Various genes, especially genes of importance to the metabolism of xenobiotic compounds, have been associated with MCS, but findings are inconsistent. The purpose of this study was to investigate genetic susceptibility factors for MCS and self-reported chemical sensitivity in a population sample. Ninety six MCS patients and 1,207 controls from a general population divided into four severity groups of chemical sensitivity were genotyped for variants in the genes encoding cytochrome P450 2D6, arylamine N-acetyltransferase 2, paraoxonase 1, methylene tetrahydrofolate reductase, and the cholecystokinin 2 receptor. No hypotheses were consistently confirmed. An apparent association between number of active cytochrome P450 2D6 alleles and MCS status was not statistically significant (OR=1.2, p=0.28). Fast arylamine N-acetyltransferase 2 metaboliser status was associated with severity of chemical sensitivity only in the most severely affected group in the population sample (OR=3.1, p=0.04). The cholecystokinin 2 receptor allele with 21 CT repeats was associated with MCS when compared in post hoc analyses with all individuals from the population sample (p=0.02). Genetic variants in paraoxonase 1 and methylene tetrahydrofolate reductase were not associated with MSC or with self-reported chemical sensitivity in the population sample. Our results suggest that variants in the genes examined are of less importance to MCS than previously reported or that gene-environment interactions or significant degrees of genetic heterogeneity in MCS underlie inconsistent findings in the literature.

Pressure-equalizing earplugs do not prevent barotrauma on descent from 8000 ft cabin altitude.

INTRODUCTION: The aim of this study was to evaluate the effect of pressure-equalizing earplugs available in major airports and drugstores. No previous study has focused on preventing barotrauma using these earplugs. METHODS: Blinded and double-blinded, one type of pressure-equalizing earplugs (JetEars) was studied in 27 volunteers disposed to ear barotrauma. They acted as their own controls with an active earplug in one ear and a placebo earplug in the other ear at random. All were exposed to the same well-defined pressure profile for 1 h at 8000 ft, comparable to the environment in civil commercial air travel in a pressurized cabin. Satisfaction was assessed by questionnaire and objective results were evaluated prior to and after the pressure exposure by tympanometry and otoscopy using the Teed classification. RESULTS: The majority of the volunteers (78%) reported a pleasant noise-reducing feeling using the earplugs. However, 75% also experienced ear pain during descent. In comparing the middle ear pressure before and after pressurization, a decrease was found in ears with both active earplugs and placebo earplugs. No difference between the active and the placebo earplugs were found. Furthermore, after evaluation of the two groups of ears using otoscopy, no prevention of barotrauma was found. In fact, the ears using an active pressure-equalizing earplug scored significantly worse (p = 0.033). CONCLUSIONS: Feelings of noise reduction were reported, but no prevention of barotrauma could be demonstrated with the use of pressure-equalizing earplugs. Pressure-equalizing earplugs cannot be recommended in air travel for preventing ear barotrauma.

Perilymphatic fistula in cabin attendants: an incapacitating consequence of flying with common cold.

A perilymphatic fistula (PLF) is an abnormal communication between the inner ear and the middle ear that leaks perilymph. PLF is considered rare, but is known to occur during childbirth, straining, weightlifting, head trauma, and diving with middle ear equalizing problems. It has also, anecdotally, been described in connection with flying. The symptoms are uncharacteristic vertigo and, in some cases, hearing impairment and tinnitus. This study describes four cases of PLF during a period of 6 mo in a major Scandinavian airline company employing approximately 3000 cabin attendants (CAs). None of the cases were diagnosed at the primary health care level. All were referred to the Aviation Medical Center for investigation. The PLF diagnosis was based on the case history, Platform Pressure Test (a fistula test), and other vestibular tests. Only one CA has been able to return to flying duties. The article emphasizes the risk of flying with poor middle ear equalization and the necessity of reminding crews and airline companies to "never fly with a common cold".

Point prevalence of barotitis and its prevention and treatment with nasal balloon inflation: a prospective, controlled study.

INTRODUCTION: The most common cause of barotitis is pressure changes induced during descent in aviation. The incidence after air flight has been reported to vary from 8% to 17%. OBJECTIVES: We conducted this study to estimate the incidence of barotitis after flight, to evaluate whether the incidence of barotitis can be reduced by nasal balloon inflation during descent, and, finally, to estimate the effect of nasal balloon inflation in case of negative middle ear pressure after landing. STUDY DESIGN: Aircraft passengers were examined by otoscopy and tympanometry before and after flying and filled in a questionnaire inquiring about ear problems. On half of the flights, the passengers were asked to inflate a nasal balloon during descent, whereas the other half were control flights. RESULTS: A total of 188 passengers filled in the questionnaire. Of these, 134 were examined before and after the flight. Otoscopic signs of barotitis were found in 15% of the ears in the control group compared with 6% in the balloon inflation group. In ears with a negative pressure after flying, the pressure could be equalized by Valsalva's maneuver in 46%. Passengers who were unable to equalize the pressure in this way inflated a nasal balloon, and in 69%, this maneuver cleared the middle ear pressure. CONCLUSION: The incidence of barotitis in this study of aircraft passengers was 14%. This figure could be reduced to 6% in passengers who performed nasal balloon inflation during descent. We recommend nasal balloon autoinflation in aircraft passengers who have difficulty clearing their ears during and after flying.

Sinus barotrauma--late diagnosis and treatment with computer-aided endoscopic surgery.

Sinus barotrauma is usually easy to diagnose, and treatment achieves good results. We present two severe cases where delayed diagnosis caused significant morbidity. The signs and symptoms were atypical and neither the patients themselves, nor the initial examiners recognized that the onset of symptoms coincided with descent in a commercial airliner. CT and MRI scans of the brain were normal, but in both cases showed opafication of the sphenoid sinuses, which lead to the correct diagnosis. Subsequent surgical intervention consisting of endoscopic computer-aided surgery showed blood and petechia in the affected sinuses. This procedure provided immediate relief.