Needle revision with and without 5-fluorouracil for the treatment of failed filtering blebs

Twelve patients with failed or failing filtering blebs were treated by transconjunctival needle revision of the bleb. Seven of these received 5-fluorouracil as an adjunct. Intraocular pressure decreased from 31.3 +/- 8.8 mm Hg (range, 20 to 47 mm Hg) to 17.0 +/- 3.7 mm Hg (range, 8 to 22 mm Hg). The length of follow-up ranged from two to 31 months. The results in 11 of 12 patients (91.6%) were satisfactory, defined by an intraocular pressure of 22 mm Hg or less, with or without antiglaucoma medications, and requiring no subsequent procedures for control of intraocular pressure. The success rates and overall pressure lowering effect of the seven patients receiving and the five patients not receiving 5-fluorouracil were similar. However, most patients receiving 5-fluorouracil were thought to be at higher risk for surgical failure. Complications of needle revision were minor and resolved without sequelae. We advocate the consideration of transconjunctival needle revision with or without the use of 5-fluorouracil as a useful therapeutic modality in the management of the failed or failing filtering bleb.

Effect of intraocular aspiration of sodium hyaluronate on postoperative intraocular pressure

A prospective, randomized, masked study was conducted to evaluate whether intraocular aspiration of sodium hyaluronate used in cataract surgery influenced postoperative intraocular pressure (IOP). Ninety-nine patients (105 eyes) underwent uncomplicated extracapsular extractions with posterior chamber intraocular lens implantation using 1% sodium hyaluronate (AMVISC). In 53 eyes, sodium hyaluronate was aspirated from the anterior chamber prior to wound closure. Sodium hyaluronate was left in the anterior chamber of 52 eyes. The IOP of 33 of the patients was measured 4 hours after surgery. No significant difference was found between the pressure in the eyes from which the sodium hyaluronate had been aspirated and the pressure in those from which it had not. The IOP of all the patients was measured on the first postoperative day. The mean 24 hours after surgery was 23.4 mm Hg in the aspirated eyes and 23.1 mm Hg in the not-aspirated group. Thirteen eyes in the aspirated group and 14 in the not-aspirated group had pressures above 30 mm Hg during the first 24 hours after surgery. There were no significant differences in visual outcome, patient discomfort, corneal clarity, anterior chamber inflammation, or subsequent IOPs during 3 months postoperative examination. Aspiration of sodium hyaluronate at the end of cataract surgery does not appear to significantly reduce either the incidence or the degree of postoperative pressure elevations.

Psychophysical changes in glaucoma

Chronic glaucoma has been thought to spare the central vision until quite late in the disease process. This assumption is based on the use of the relatively insensitive Snellen chart to measure central vision and the relatively sensitive kinetic and static perimetry to measure the peripheral vision. In recent years, new measures of visual function have been utilized to assess patients with glaucomatous damage. Sensitive methods of measuring central visual function such as color vision, contrast sensitivity (both spatial and temporal), and macular light sensitivity have demonstrated defects early in the glaucomatous process - sometimes even before perimetry is affected. Since these visual functions are largely mediated by macular fibers, central vision may be affected earlier and more frequently in glaucoma than previously believed. Studies of both the nerve fiber layer of the retina and of quantitative light sense perimetry suggest that glaucomatous damage may occur diffusely across the population of nerve fibers, focally in the arcuate portion of the nerve fiber layer, or in both places. Color vision, contrast sensitivity and macular light sense appear to correlate with the diffuse type of nerve fiber layer damage. The exact utility of the psychophysical tests that assess central visual function for the clinical management of glaucoma has not yet been demonstrated. More work is needed to determine which tests are most useful, what parameters are most efficient, and what the diagnostic and prognostic significance of abnormal values may be. However, the studies of color vision, contrast sensitivity and macular light sensitivity have led to a better understanding of how glaucoma affects visual function.

Chemotactic activity in aqueous humor from patients with anterior uveitis

Anterior uveitis, inflammation of the iris or ciliary body of the eye, may be associated with a variety of systemic diseases. Although a leukocytic infiltrate is characteristic of anterior uveitis, few studies have sought to detect factors in aqueous humor that could attract neutrophils or monocytes into the anterior chamber. Using modified Boyden chambers, we found that a 5% concentration of aqueous humor from patients with anterior uveal inflammation induced monocyte movement comparable to optimal or near-optimal concentrations of C (complement)5a or platelet-derived growth factor. Aqueous humor from patients with anterior uveitis induced significantly more monocyte migration than did aqueous humor from two sets of controls (either patients undergoing cataract extraction or patients with posterior uveitis). "Checkerboard" or gradient analysis indicated that a majority of inflammatory disease samples induced monocyte chemotaxis (directed migration) while the control aqueous humor consistently induced chemokinesis (stimulated random migration) (P less than 0.02). Despite their ability to induce monocyte migration, samples tended to induce minimal neutrophil migration with the exception of aqueous humor that was obtained from one patient with acute anterior disease. This sample induced marked chemokinesis. Identification of chemotactic activity may clarify the pathogenesis of uveitis and the characterization of leukocyte migration factors in aqueous humor may help define subsets of anterior uveal inflammation.

The corneal endothelium and Descemet's membrane in the iridocorneal endothelial syndrome

A 39-year-old woman with progressive left unilateral glaucoma associated with corneal edema, iris changes, and peripheral anterior synechia formation underwent a left trabeculectomy and iridectomy in an attempt to control the intraocular pressure. Shortly after surgery the edema worsened despite low intraocular pressure measurements. A repeat trabeculectomy combined with a full thickness keratoplasty was performed 11/2 years later. The posterior corneal surface was found to be covered by a partially doubled layer of endothelial cells with ultrastructural features resembling epithelium. Similar cells were not noted on the surface of the initial trabecular meshwork and iris specimens, but were seen on the surface of the specimens obtained at the second trabeculectomy. The anterior and middle portions of Descemet's membrane, formed during perinatal and early adult life, appeared normal, but its posterior portion appeared abnormal. The ultrastructural changes in the endothelial cells and the abnormalities observed in Descemet's membrane suggest that the endothelial cells were initially normal but subsequently acquired epithelial-like features as they degenerated and proliferated. The continued presence of corneal edema despite the hypercellularity of the endothelium suggests that the proliferating cells were permeable to aqueous.

The effect of glaucoma on central visual function

Glaucoma has traditionally been thought to affect peripheral visual function in its early stages and to spare central visual function until late in the disease process. The basis for this assumption has been the reliance on Goldmann-type perimetry, a rather sensitive method for assessing the peripheral visual function, and on Snellen-type visual acuity measurements, a rather insensitive method of assessing central visual function. This belief has persisted despite frequent complaints from patients with glaucoma that their central vision is disturbed. Over the past two decades, several investigations of central visual functions and their anatomic substrate have challenged this assumption. Histologic studies of the nerve fiber layer in eyes with glaucoma suggest that the number of ganglion cells subserving macular function is decreased even in early stages of the disease. In addition, afferent pupillary defects (a gross measurement of macular nerve fiber function) may also be present in eyes with early glaucoma. Several studies have demonstrated that color perception (largely mediated by the fovea) is defective in glaucoma. Furthermore, defects in color perception may even precede the development of visual field abnormalities. Seventy-eight percent of patients with early glaucomatous visual field defects were found to have a defect in color perception when tested with a desaturated D-15 color panel that tests only the central 1.5 degrees. In addition, both chromatic and achromatic foveal perception channels are defective in eyes with glaucoma and even in some eyes of those with suspected glaucoma. Contrast sensitivity has become recognized as an important component of visual function. Partial loss of contrast sensitivity may cause a degradation in the quality of perception even though the Snellen visual acuity remains normal. Although contrast sensitivity is not entirely a macular function, it has been shown that as little as 3 degrees of disturbance of the macula (eg, with macular degeneration or with an artificial central scotoma) will reduce the contrast sensitivity, suggesting that this modality is indeed mediated to a significant extent by this portion of the retina. Spatial contrast sensitivity appears to be reduced in patients with glaucoma. However, because of overlap and lack of a sharp cutoff measurement, present testing procedures fail to allow a clear distinction between the glaucomatous and normal populations. Although reduced temporal contrast sensitivity has been demonstrated in glaucomatous eyes by others, I undertook a systematic investigation of this function in a large group of patients with glaucoma and with suspected glaucoma.(ABSTRACT TRUNCATED AT 400 WORDS)

Arden contrast sensitivity testing in glaucoma

Two hundred sixteen eyes (164 patients) were studied with the Arden printed contrast gratings to test Arden's hypothesis that an abnormal score would distinguish between eyes with and without glaucoma. Ninety-five eyes were normal and 75 eyes were glaucomatous; 46 eyes suspected of being glaucomatous were also studied to determine whether such eyes would score differently than eyes with normal intraocular pressures. No age-dependent trend in scoring was found in the different diagnostic categories, except with the age group younger than 40 years, which had consistently better contrast sensitivity. The tests were demonstrated to be reproducible over time and showed little or no intertester variability. Decreased contrast sensitivity was found in the glaucomatous eyes compared with normal eyes. The scores of the eyes suspected of being glaucomatous fell between the scores of the glaucomatous and normal eyes. Overlapping distributions among the three groups, however, limit the diagnostic value of the test.

The effect of calcium dobesilate on nonproliferative diabetic retinopathy: a controlled study

Two independent, double-masked, controlled studies were made to evaluate the efficacy of calcium dobesilate for the treatment of nonproliferative diabetic retinopathy. Forty-two patients underwent a six-month crossover evaluation while receiving calcium dobesilate (750 mg per day) and placebo in random order. Thirty-six patients received calcium dobesilate (1,000 mg per day) or placebo for one year. Evaluation by clinical examination, fluorescein angiography, angiography, and fundus photography failed to demonstrate any beneficial effect of calcium dobesilate.