Forty-one normal humans were tested with sinusoidal harmonic acceleration. Phase lag at 0.01, 0.02, and 0.04 Hz was the most stable parameter, with less test-retest variability than gain and asymmetry. There was no significant difference between men and women for phase lag, gain, or asymmetry at any of the five testing frequencies. Gain decreased as age increased. Age had no effect on phase lag at most test frequencies or on asymmetry at any frequency.

Tonsillectomy in a young adult group results in significant improvement in overall quality of life, physical health and general well-being.

Background -There is evidence that administration of higher doses of aminoglycosides given less frequently improves the bactericidal effect and reduces the potential to cause side effects. To investigate this, a prospectively randomised open label therapeutic trial was undertaken in stratified groups of patients with cystic fibrosis to examine the efficacy and toxic potential of an aminoglycoside dosing regimen designed to generate high peak drug concentrations at 12 hourly intervals compared with conventional dosing at eight hourly intervals. Methods -Patients in group A received tobramycin eight hourly using a dose aimed at generating a peak concentration of 10 mgIl with trough concentrations below 2 mglI, and those in group B received the total daily dose required to achieve eight hourly target concentrations administered as two equal 12 hourly doses. Clinical outcomes measured and assessed included vestibular symptoms, hearing and renal function, length of hospital stay, readmission rate, and mortality. Results -Twenty nine patients were recruited during a six month period, 20 to group A and nine to group B. The average peak tobramycin level was higher in group B (12.5 (2.2) mgIl) than in group A (7.9 (1.9) mgIl), whilst the average trough level was higher in group A (0-8 (0.3) mgIl) than in group B (0-5 (0.2) mg/l). There was a difference in the number ofototoxic events between patients in group A (seven of 18, 38c9%) and group B (none of eight), but no difference was found in other outcome measures assessed. Conclusions -These results suggest that 12 hourly high peak aminoglycoside dosing may be less toxic than equivalent eight hourly dosing, without any apparent difference in efficacy. (Thorax 1996;51:369-373) Keywords: aminoglycosides, cystic fibrosis, ototoxicity.Aminoglycoside antibiotics provide an effective and inexpensive treatment for Gram negative infections, yet their usefulness as antibiotics has been limited by their potential to cause ototoxicity and nephrotoxicity. }6ere is evidence from both human and animal models that larger doses of aminoglycosides given less frequently reduce their potential to cause such side effects.4"'7 The efficacy of larger less frequent aminoglycoside dosing regimens becomes a concern in patient groups whose clearance of the drug makes the interdose interval more critical, and these patient groups must be included in any rational analysis of this issue. Patients with cystic fibrosis represent such a group.The primary pathogens implicated in the chronic lung infection associated with cystic fibrosis are Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and Pseudomonas aeruginosa, the latter being responsible for chronic infection in 70-90% of all these patients.""24 P aeruginosa undergoes phenotypic adaptation within the lungs of patients with cystic fibrosis, the most important being the emergence of mucoid strains. The aim of this study was to examine the efficacy and toxic potential of a dosing regimen oftobramycin which generate...