Canal networks as extended waste stabilization ponds: fate of pathogens in constructed waterways in Pathumthani Province, Thailand.

The occurrence and fate of surface water and wastewater pathogens (faecal coliforms, Escherichia coli, Giardia lamblia and Cryptosporidium parvum) in two constructed waterways and a pond-based AIT wastewater treatment plant (AIT WWTP) in Pathumthani, Thailand were studied in the context of several biogeochemical factors and in relation to pollutional pressure and seasonal phenomena with a view to proposing potential mechanisms for their removal. More data on pathogen removal in a given local context would provide assurance that some pathogens could serve as suitable indicator organisms and predict removal of different pathogenic microorganisms such as protozoan parasites covered in this study. The enumeration technique for protozoan pathogens was improved in terms of application of emerging novel molecular technologies for the development of a fast but affordable microbiological method. Potential risk of waterborne disease outbreak in pertinent communities was then characterized using established infection probability models and the compiled pathogen occurrence data. Overall, we have addressed several strategic priorities of pathogen research in waste stabilization ponds in developing tropical countries like

Bleb window cryopexy for the management of oversized, misplaced blebs.

PURPOSE: To describe a new technique for revising oversized blebs after trabeculectomy. METHODS: A chart review of consecutive patients undergoing bleb window cryopexy was conducted. Patients with symptomatic oversized blebs were candidates for the technique, regardless of the intraocular pressure. Under topical anesthesia, the bleb was incised and a 3 mm x 3 mm conjunctival window was removed using 0.12 forceps and Vannas scissors. Light cryotherapy was applied to the sclera through the window. A soft bandage contact lens was then placed for compression, and a patch was applied. All patients were given antibiotic drops the first day after surgery. Topical corticosteroid drops were used to minimize postoperative inflammation. Outcome measures included relief of symptoms, adequate control of intraocular pressure, and restoration of filtering bleb function without further antiglaucoma medication or surgical bleb revision. RESULTS: Nine patients met the inclusion criteria. All patients had flattening of the bleb with symptomatic relief within 2 weeks. No loss of bleb function occurred. One patient developed aqueous misdirection after the procedure. CONCLUSION: Early results showed that bleb window cryopexy is safe and effective. This minimally invasive technique can be useful for selected patients with large. symptomatic, overhanging blebs.