Detecting the inner and outer borders of the retinal nerve fiber layer using optical coherence tomography.

Background: The purpose of this study was to develop a new algorithm to detect the inner and outer borders of the retinal nerve fiber layer (RNFL) using optical coherence tomography (OCT).

Methods: A program featuring a new algorithm was developed using a commercially available software development environment. The algorithm searches for peaks on each sampling line instead of applying conventional thresholding techniques.

Ultrasound biomicroscopy in uveitis-glaucoma-hyphema syndrome.

Purpose: To assess anterior segment anatomy in uveitis-glaucoma- hyphema syndrome.

Design: Retrospective case series.

Methods: Nine pseudophakic eyes (nine patients) with complete or incomplete uveitis-glaucoma-hyphema syndrome underwent ultrasound biomicroscopy.

Ultrasound biomicroscopy before and after goniosynechialysis.

Purpose: To report the ultrasound biomicroscopic appearance of the anterior chamber angle before and after successful goniosynechialysis.

Methods: Interventional case report. Ultrasound biomicroscopy using a 50-MHz transducer was performed in the supine position preoperatively and postoperatively in a 76-year-old woman with angle-closure glaucoma.

Retinal nerve fiber layer thickness remains unchanged following laser-assisted in situ keratomileusis.

Purpose: To evaluate the effect of laser-assisted in situ keratomileusis (LASIK) on retinal nerve fiber layer (RNFL) thickness measurements obtained with scanning laser polarimetry (SLP), optical coherence tomography (OCT), and scanning laser tomography (SLT).

Design: Interventional case series.

Methods: Twenty eyes (20 patients) undergoing LASIK were enrolled in this prospective study.

Retinal pigment epithelial dysfunction in patients with pigment dispersion syndrome: implications for the theory of pathogenesis.

Objective: To test the hypothesis that the retinal pigment epithelial/photoreceptor complex is affected in patients with pigment dispersion syndrome and/or in patients with pigmentary glaucoma.

Methods: Electro-oculograms were recorded from patients with pigment dispersion syndrome, pigmentary glaucoma, ocular hypertension, and primary open-angle glaucoma and from control subjects. Electro-oculograms were recorded during 15 minutes of dark adaptation followed by 15 minutes of light adaptation.

Diode laser transscleral cyclophotocoagulation for refractory glaucoma.

Purpose: To evaluate the efficacy of contact diode laser transscleral cyclophotocoagulation using different treatment parameters.

Methods: All eyes undergoing contact diode laser transscleral cyclophotocoagulation between April 1991 and September 1997 at our two institutions were enrolled. Success was defined as an intraocular pressure less than or equal to 22 mm Hg or absence of pain for poorly sighted and blind eyes.

Glaucoma drainage tube kink after pars plana insertion.

Purpose: To describe focal obstruction of drainage tubes by kinking at the scleral entry site after pars plana insertion.

Methods: Case study.

Results: Three eyes of three patients underwent uncomplicated placement of a Baerveldt implant into the vitreous cavity at the time of pars plana vitrectomy.

Vitreous opacities affect scanning laser polarimetry measurements.

Purpose: To assess the effect of vitreous opacities on retinal nerve fiber layer retardation measurements obtained during scanning laser polarimetry.

Methods: Scanning laser polarimetry was performed in two eyes of two patients with vitreous opacities.

Results: The presence of a vitreous opacity within the measurement ellipse during scanning caused a marked, localized increase in polarization in the area of the opacity.

Ultrasound biomicroscopic diagnosis of cyclitic membranes.

Purpose: To evaluate the utility of ultrasound biomicroscopy in imaging cyclitic membranes.

Methods: Patients with hypotony and suspected or known cyclitic membrane underwent ultrasound biomicroscopic examination. Histopathology of cyclitic membrane was correlated with ultrasound biomicroscopy in three cases.

Attempted eyelid closure affects intraocular pressure measurement.

Purpose: To evaluate the effect of attempted eyelid closure on intraocular pressure measurement.

Methods: Normal subjects underwent intraocular pressure measurement in both eyes using Goldmann applanation tonometry and Tono-pen XL (Mentor, Inc, Norwell, Massachusetts) by the same examiner holding the eyelids open, both with and without the subject simultaneously attempting forced eyelid closure. Subjects were seated during all measurements and waited 5 minutes between measurements with each instrument; the order of measurement was randomized.

Iris and ciliary body melanomas: ultrasound biomicroscopy with histopathologic correlation.

Objective: To correlate ultrasound biomicroscopic images of iris and ciliary body melanomas with their histopathologic features.

Methods: Ultrasound biomicroscopy was performed in 3 cases of iris melanoma and in 3 cases of ciliary body melanoma. Cross-sectional ultrasound biomicroscopic images were compared with findings from clinical examination and light microscopy to evaluate associations between their histopathologic, surface, and internal ultrasound characteristics.

The use of scleral transillumination to localized the extent of a cyclodialysis cleft.

Several techniques have been described to localize and repair cyclodialysis clefts. We describe a technique that may be used to easily and accurately localize a cyclodialysis cleft using scleral transillumination. We have verified the accuracy of this technique using high frequency ultrasound biomicroscopy.

Inadvertent corneal indentation can cause artifactitious widening of the iridocorneal angle on ultrasound biomicroscopy.

A 70-year-old Asian female with narrow angles underwent ultrasound biomicroscopy (UBM) darkroom provocative testing. The angle was narrow under light conditions and occluded in the dark, except for the inferior quadrant where the angle was wide and the iris concave. This was reproducible in four quadrants with the use of a small UBM eye cup but not the large one.

Assessment of retinal nerve fiber layer internal reflectivity in eyes with and without glaucoma using optical coherence tomography.

Objective: To assess the internal reflectivity of the retinal nerve fiber layer in normal, ocular hypertensive, and glaucomatous eyes using optical coherence tomography.

Methods: All patients underwent complete ophthalmic examination and achromatic automated perimetry. Intraocular pressure was 21 mm Hg or less for low-tension glaucoma and normal eyes and at least 25 mm Hg on 2 separate occasions in ocular hypertensive and high-tension glaucoma eyes.

A uniform format for ocular imaging devices.

Purpose: To develop a uniform file format of ocular imaging data, including, but not limited to, ultrasound biomicroscopy, optical coherence tomography, and nerve fiber analyzer, capable of being transmitted via Internet or intranet for collaborative research and telemedicine use.

Method: File filters were developed as dynamic link libraries (DLLs). These can read the original raw data format of each ocular imaging device.

Low-dose 5-fluorouracil trabeculectomy as initial surgery in uncomplicated glaucoma: long-term followup.

Objective: To compare the effectiveness of trabeculectomy with adjunctive, low-dose, subconjunctival 5-fluorouracil (5-FU) to trabeculectomy alone in patients with uncomplicated glaucoma undergoing their first incisional surgical procedure.

Design: Retrospective, nonrandomized comparative trial.

Participants: Consecutive series of 52 patients and 74 control subjects.

Quantitative assessment of the anterior segment using ultrasound biomicroscopy.

The development of ocular imaging devices has progressed rapidly during the past 10 years. Ultrasound biomicroscopy has revolutionized the evaluation of the anterior segment of the eye. The qualitative information gathered using this technology has contributed to our understanding of the pathophysiology of angle-closure glaucoma, pigmentary glaucoma, and a variety of other anterior segment disorders.

Grayscale and proportion-corrected optical coherence tomography images.

Background And Objective: The commercially available optical coherence tomography (OCT) scanner displays images in a pre-set window regardless of the projected scan length on the retinal surface. The aim of this study was to demonstrate the true dimensions of proportion-corrected OCT images and the additional information present in grayscale images.

Materials And Methods: OCT raw data were exported to an IBM-compatible PC and processed to show grayscale and proportion-corrected images using an automated software of our own design.