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Five of 16 patients who had uncomplicated cataract extraction with intraocular lens (IOL) implantation within a 2.5 day period experienced increased anterior segment inflammation on their first postoperative day. Four of these five patients had phacoemulsification and one a planned extracapsular cataract extraction. All had posterior chamber IOL implantation in the capsular bag. In all patients, this anterior segment inflammation cleared with topical steroids over two to three weeks with no evident residual ocular effects. A careful search for the possible cause of the inflammation showed that the ultrasonic cleaning bath and Weck liquid detergent used to clean the instruments contained Klebsiella pneumoniae bacteria. Further investigation demonstrated the presence of a heat-stable endotoxin produced by the bacteria. We postulate that endotoxin remaining on the instruments after cleaning and sterilization caused this postoperative anterior segment inflammation. To the best of our knowledge, these are the first reported cases caused by contaminated liquid detergent.

Cognitive radio (CR) has the potential for resolving the spectrum scarcity issue in wireless communications. A CR device can establish unharmful links in the spectrum of the legacy system. Among many enabling functions for CR, spectrum handoff can restore CR's connection when the primary user appears in the occupied channel. In this paper, we study three types of spectrum handoff for the link maintenance: (1) nonspectrum handoff method, (2) the pre-determined channel list spectrum handoff, and (3) the spectrum handoff based on radio sensing scheme. We examine the performances of the three mechanisms in terms of the link maintenance probability and the effective data rate of the secondary user's transmission. Our numerical results show that erroneous channel selection probability, radio sensing time and the number of handoff trials are important for spectrum handoff schemes. We also provide the design guideline for these parameters .