An optical evaluation technique is described that is suitable for determining the positions and magnitudes of reflection sites within miniature optical assemblies. This method utilizes the coherence effects exhibited by a broadband optical source and is referred to as optical coherence-domain reflectometry. Background theory is given, and experimental results have demonstrated a resolution of 10 microm with an optical dynamic range of more than 100 dB.

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SummaryThe number of neurolytic coeliac plexus blocks carried out in England and Wales over a 5 year period (1986)(1987)(1988)(1989)(1990) was ascertained. The number of cases of the major complications of permanent paraplegia and/or loss of anal and bladder sphincter function following on from such blocks, over the same period of time, was also ascertained. The information was obtained by means of a questionnaire which was sent to most of the pain clinics in England and Wales. There were 2730 neurolytic blocks carried out over the 5 year period. The number of cases of permanent paraplegia following on from the blocks was four. Of these four cases, three of them also had loss of anal and bladder sphincter function -loss of sphincter function never occurred in isolation. The incidence of major complications following neurolytic coeliac plexus block was thus one case per 683 blocks.

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