Faculty Bibliography

PURPOSE: This study examined physician hygiene patterns in the eye clinic of a major medical center to assess compliance with recommended practice patterns to avoid nosocomial infection during patient encounters. METHODS: One hundred ophthalmology resident-patient encounters were observed anonymously by the authors. Examining physicians were evaluated in handwashing between patients, cleaning and disinfecting of tonometer tips after each use, and recapping of diagnostic drop bottles after each use. RESULTS: Physicians washed their hands 74% of the time between patient encounters. The surfaces of tonometer tips were disinfected with an alcohol pad 100% of the time. Diagnostic drop bottles were recapped 57% of the time after each use. CONCLUSIONS: There is ample clinical evidence in the ophthalmic literature that practitioners' hands and tonometer tips can be vectors for transmission of nosocomial infection and that vigorous handwashing and disinfection of instruments can decrease the rates of transmission. Sometimes, however, physicians neglect to follow these simple and effective steps. We suggest posting visual educational materials in examination rooms as a reminder to ophthalmology residents and clinic personnel to adhere to these precautions, benefiting doctors and patients

BACKGROUND: Most patients with central serous chorioretinopathy (CSC) have spontaneous resolution of exudative macular detachments and a good visual prognosis. Patients with CSC have a primary choroidal hyperpermeability problem evident as multifocal areas of hyperpermeability during indocyanine green (ICG) angiography. A small percentage of patients develop chronic or progressive disease with widespread decompensation of the retinal pigment epithelium and severe vision loss. There is no known treatment for this variant of the disorder. PURPOSE: To study ICG-guided photodynamic therapy (PDT) with verteporfin as a potential treatment for patients with chronic CSC. METHODS: Twenty eyes of 15 patients were studied with fluorescein angiography, optical coherence tomography, and ICG angiography to diagnose the maculopathy, monitor the detachments, and localize the choroidal hyperpermeability of the disorder. PDT with ICG guidance was applied to areas of choroidal hyperpermeability, and the patients were observed to determine the anatomic and functional outcomes. RESULTS: Photodynamic therapy guided by ICG was associated with complete resolution of exudative macular detachments in 12 patients and incomplete resolution in the remaining eight eyes. The vision improved in six eyes and remained unchanged in 14 eyes during a mean follow-up of 6.8 months. Six weeks after treatment, the mean visual acuity improved by 0.55 lines, an amount that was marginally significant. There was a significant inverse correlation between the baseline visual acuity and the amount of improvement in acuity at 6 weeks. No patient had any treatment-related side effects. CONCLUSIONS: Indocyanine green angiography-guided PDT with verteporfin seems to aid in the resolution of exudative detachments in patients with chronic CSC. This treatment was associated with a rapid reduction in subretinal fluid and improvement in visual acuity. Although the follow-up time and number of patients in this pilot study were limited, the encouraging results and lack of complications suggest that further study is indicated

The mechanism of cell death induction by dimethyl tetrahydroxyhelianthrone (DTHe), a new second-generation photodynamic sensitizer, is analysed in human leukaemic cell lines in comparison with the structurally related hypericin. DTHe has a broad range of light spectrum absorption that enables effective utilization of polychromatic light. Photosensitization of HL-60 cells with low doses of DTHe (0.65 microM DTHe and 7.2 J cm(-2) light energy) induced rapid apoptosis of > or =90% of the cells. At doses > or =2 microM, dying cells assumed morphological necrosis with perinucleolar condensation of chromatin in HL-60 and K-562 cell lines. Although nuclear fragmentation that is characteristic to apoptosis was prevented, DNA digestion to oligonucleosomes proceeded unhindered. Such incomplete apoptosis was more prevalent with the related analogue hypericin throughout most doses of photosensitization. Despite hypericin being a stronger photosensitizer, DTHe exhibited advantageous phototoxic properties to tumour cells, initiating apoptosis at concentrations about threefold lower than hypericin. Photosensitization of the cells induced dissociation of the nuclear envelope, releasing lamins into the cytosol. DTHe also differed from hypericin in effects exerted on the nuclear lamina, causing release of an 86-kDa lamin protein into the cytosol that was unique to DTHe. Within the nucleus, nuclear envelope lamin B underwent covalent polymerization, which did not affect apoptotic nuclear fragmentation at low doses of DTHe. At higher doses, polymerization may have been extensive enough to prevent nuclear collapse. Hut-78, CD4+ cells were resistant to the photodynamically activated apoptotic pathway. Beyond the tolerated levels of photodynamic damage, these cells died exclusively via necrosis. Hut-78 cells overexpress Bcl-X(L) as well as a truncated Bcl-X(L)tr isoform that could contribute to the observed resistance to apoptosis