Hall F. Chew

Comparison of photodynamic therapy and transpupillary thermotherapy for subfoveal choroidal neovascularization due to age-related macular degeneration

BACKGROUND The purpose of this study was to compare photodynamic therapy (PDT) against subthreshold transpupillary thermotherapy (TTT) with a diode laser for subfoveal choroidal neovascularization secondary to age-related macular degeneration (AMD). METHODS Patients with subfoveal choroidal neovascularization secondary to AMD were offered PDT as an initial intervention. If they declined PDT, then TTT was offered. RESULTS We evaluated and followed 115 consecutive patients for an average of 1 year. The primary outcome measure was visual acuity, but the interventions were also compared on the basis of lesion size and angiographically determined lesion activity. Baseline comparisons between the 2 treatment groups showed significant differences in pretreatment visual acuity, lesion size, and lesion composition. Univariate analysis of outcomes demonstrated equivalence between the treatment groups in final lesion size, angiographic activity, and visual acuity. Multivariate analysis also demonstrated equivalence between the treatment groups in final visual acuity while controlling for age, pretreatment visual acuity, and lesion category. Predominantly classic lesions were associated with poorer visual outcomes. INTERPRETATION The PDT and TTT groups were equivalent in terms of all outcome parameters evaluated.

Socioeconomic status and clinical features of patients undergoing photodynamic therapy or transpupillary thermotherapy for subfoveal choroidal neovascularization due to age-related macular degeneration.

BACKGROUND The purpose of this study was to compare baseline clinical and socioeconomic features of patients undergoing self-funded photodynamic therapy (PDT) or government-funded subthreshold transpupillary thermotherapy (TTT) with a diode laser for subfoveal choroidal neovascularization secondary to age-related macular degeneration (AMD). METHODS Between July 2000 and August 2001, 115 patients with subfoveal choroidal neovascularization secondary to AMD were offered PDT as an initial intervention. If individuals believed that they could not afford or did not want PDT, then TTT was offered. In masked fashion, leakage pattern and lesion size were determined retrospectively from pretreatment angiograms. Baseline visual acuity was determined with autorefraction and subsequent Snellen testing. The mean income of each treatment group was estimated from the average sex-specific income for each subjects postal code, based on the 1996 Canadian census data. The average education level for each subjects postal code was also determined. RESULTS The patients who were not willing to pay for PDT had significantly worse macular disease before treatment (larger lesions and poorer visual acuity) and a significantly lower mean income than the patients who were willing to pay for PDT. INTERPRETATION The severity of exudative choroidal neovascularization appears to be associated with lower socioeconomic status.

Fungal keratitis caused by Metarhizium anisopliae complex

Purpose To report a case of fungal keratitis caused by Metarhizium anisopliae complex Methods Case report Results Our patient presented with a central corneal infiltrate. Fungal culture yielded a Metarhizium species. She was started on antifungal agents with no significant improvement. A therapeutic corneal transplant was performed after perforation. At two years follow up, she was free of infection. Conclusion Metarhizium anisopliae is a very rare cause of keratitis. Although previous reported cases showed clinical improvement with antifungal agents, this case required surgical treatment to control the infection.

Limbal stem cell disease: Treatment and advances in technology

Anterior segment stem cell technology, due to its already well-defined corneal limbal stem cells with greater ease of evaluation, has been at the forefront of ophthalmic stem cell treatment and technology since 1997. This paper provides an overview of the current standard of care for treatment of limbal stem-cell deficient conditions and reviews recent treatment technologies using ex vivo expansion of cultivated limbal stem cells of the cornea.

Glaucoma after corneal replacement

Glaucoma is a well-known complication after corneal transplantation surgery. Traditional corneal transplantation surgery, specifically penetrating keratoplasty, has been slowly replaced by the advent of new corneal transplantation procedures: primarily lamellar keratoplasties. There has also been an emergence of keratoprosthesis implants for eyes that are high risk of failure with penetrating keratoplasty. Consequently, there are different rates of glaucoma, pathogenesis, and potential treatment in the form of medical, laser, or surgical therapy.