PubMed Health⌕ Search

Biomedical subjects

Richard K Lee

Publications and source records attributed to Richard K Lee.

5 recordsLinked to original sources

Glaucoma drainage implants: a critical comparison of types.

PURPOSE OF REVIEW: The purpose of this review is to critically compare the various glaucoma drainage implants in popular use. RECENT FINDINGS: Glaucoma drainage implants are being increasingly utilized in the surgical management of glaucoma. Comparisons between the various drainage implants are difficult because most clinical data are derived from retrospective studies with different study populations, follow-up periods, and criteria defining success. The type of glaucoma under treatment is a major factor influencing surgical outcomes. The resistance to aqueous flow through glaucoma drainage implants occurs across the fibrous capsule around the end plate, and the major determinants of the final intraocular pressure are capsular thickness and filtration surface area. The use of antifibrotic agents as adjuncts to drainage implant surgery has not proven effective in modulating capsular thickness. Valved implants appear to reduce, but do not eliminate, the risk of hypotony. Bleb encapsulation is more frequently seen with the Ahmed valve implant than other drainage implants. Diplopia was a common complication with the Baerveldt glaucoma implant after its introduction, but design modifications have markedly reduced the incidence of this complication. SUMMARY: There are several glaucoma drainage implants that are currently available, and all have been shown to be safe and effective in reducing intraocular pressure. Greater pressure reduction may be achieved with implants with larger end plates, and valved implants appear to reduce the risk of postoperative hypotony.

Aqueous Humor↗

Glaucoma screening: current trends, economic issues, technology, and challenges.

PURPOSE OF REVIEW: Glaucoma is one of the leading causes of irreversible blindness worldwide. Early glaucoma detection and treatment are currently the only known methods for preventing blindness and low vision resulting from this frequently asymptomatic disease. RECENT FINDINGS: New technologies for detecting early glaucomatous damage are important in diagnosing optic nerve disease, not only in community screening settings but also in clinics. Imaging of the optic nerve head and macula and retinal nerve fiber layer analysis can provide quick, automated, and quantitative measurements in agreement with clinical estimates of optic disc structure and visual function. In the area of perimetry, frequency-doubling technology is a promising and feasible mass-screening method with reasonable sensitivity for detecting visual field loss. Central corneal thickness has emerged as a new risk factor for the development and progression of glaucoma, thereby complicating the role of tonometry and measurement of intraocular pressure as screening parameters for glaucoma. Along with technological advances, strides are also being made with public policy and legislative efforts to bring glaucoma onto the national and global health care agenda. These initiatives incorporate vision-screening goals into national disease prevention programs emphasizing the need for early glaucoma detection and treatment. SUMMARY: Glaucoma awareness needs to be increased through better education, and compliance with follow-up care needs to be improved to decrease the economic and social costs from glaucoma. In addition, screening models need to be developed that will be effective in developing countries where the risk of blindness from glaucoma is highest.

Biomedical Technology↗

Surgical management of patients with combined glaucoma and corneal transplant surgery.

The reasons for having combined glaucoma and corneal transplant surgery are myriad. Patients with corneal transplants have a high frequency of developing secondary glaucoma. Patients with preexisting glaucoma have even higher risk for developing glaucoma refractory to medical management after penetrating keratoplasty. The indication for corneal transplant affects the risk for developing postkeratoplasty glaucoma. The surgical treatment options for treating glaucoma include laser trabeculoplasty, cycloablation, trabeculectomy, and glaucoma drainage implants. In addition, the sequencing of glaucoma surgery relative to penetrating keratoplasty affects the outcome. Newer corneal transplant techniques may have a lower risk for developing secondary glaucoma.

Ciliary Body↗