Efficacy of middle-ear packing in success of type 1 tympanoplasty: a prospective randomised study.

OBJECTIVE: A prospective randomised study was undertaken to compare the results of type 1 tympanoplasty with and without middle-ear packing with gelfoam. METHOD: Eighty patients undergoing type 1 tympanoplasty were randomised into two groups according to packing in the middle ear: with gelfoam and without gelfoam. The data in terms of graft uptake rate, hearing gain and subjective improvement were analysed at one and three months. RESULTS: The graft uptake rate between both groups did not show a statistically significant difference. There was conductive hearing loss in the gelfoam group in the early post-operative period. Subjectively, patients were more comfortable with respect to heaviness and hearing gain than in the non-gelfoam group. CONCLUSION: Gelfoam use in middle-ear packing is not an essential step and causes more discomfort in patients during the early post-operative period. It should be a surgeon's choice to use it when and where it is necessary.

Scaling studies of nano dots formed on InP(111) surfaces via MeV implantation.

The scaling parameters have been studied here for InP(111) surfaces that evolve after implantation with MeV ions. The surfaces show the development of nano pattern and kinetic roughening. Growth exponent beta, roughening exponent alpha and the characteristic wavelength have been studied here at several fluences. Scaling parameters suggest that the surface evolution can not be explained by linear Bradley Harper model or by Kuramoto-Sivashinsky model alone.

Studies of self-organized nanostructures on InP(111) surfaces after low energy Ar+ ion irradiation.

We report formation of self organized InP nano dots using 3 keV Ar+ ion sputtering, at 15 degrees incidence from surface normal, on InP(111) surface. Morphology and optical properties of the sputtered surface, as a function of sputtering time, have been investigated by Scanning Probe Microscopy and Raman Scattering techniques. Uniform patterns of nano dots are observed for different durations of sputtering. The sizes and the heights of these nano dots vary between 10 to 100 nm and 20 to 40 nm, respectively. With increasing of sputtering time, t, the size and height of these nano dots increases up to a certain sputtering time t(c). However beyond t(c), the dots break down into smaller nanostructures, and as a result, the size and height of these nanostructures decrease. The uniformity and regularity of these structures are also lost for sputtering beyond t(c). The crossover behavior is also observed in the rms surface roughness. Raman investigations of InP nano dots reveal optical phonon softening due to phonon confinement in the surface nano dots.