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Purpose: To determine the effect of taxol and etoposide, hydrophobic drugs with antifibrosis activity, on the outcome of filtration surgery in glaucomatous monkeys., Methods: Elevated intraocular pressure was produced bilaterally in eight cynomolgus monkeys by laser treatment of the trabecular meshwork. Four animals subconjunctivally received a polyanhydride disk containing 1 mg etoposide at the time of posterior lip sclerectomy in one eye; the other eye received an identical disk without drug. Similarly, four animals received a disk containing 50 micrograms of taxol in one eye and a blank disk in the other., Results: Eyes treated with taxol had lower intraocular pressures than control eyes from 20 days after surgery until death. Eyes with satisfactory filtration bleb appearance and patent fistulae on histologic examination had lower intraocular pressures. The intraocular pressure was lower and the duration of success longer in the etoposide-treated eyes (mean, 16 days) compared to that of the fellow eyes (mean, 10 days), but the difference was not statistically significant., Conclusions: Use of polyanhydride disks containing taxol, but not etoposide, had a marked beneficial effect on intraocular pressure and bleb appearance after experimental filtration surgery in monkeys. The difference between the two agents may result from the greater antiproliferative potency of taxol and its greater duration of release from the polymer.

Purpose: To determine the distribution of transforming growth factor type beta (TGF-beta) in the anterior segment of the human eye. This knowledge is important because TGF-beta may regulate various physiologic responses in the anterior segment by controlling cell proliferation and differentiation, angiogenesis, and extracellular matrix composition., Methods: Immunohistochemical methods were used to localize the beta 1, beta 2, and beta 3 isoforms of TGF-beta in the anterior segment of the human eye., Results: Eight of eight eyes (six eye bank specimens and two eyes enucleated because of choroidal melanoma) exhibited staining for at least one of the TGF-beta isoforms. TGF-beta 1 was found in superficial limbal epithelial cells (four of eight eyes) and in the stroma proximal to the ciliary processes (seven of eight eyes). TGF-beta 2 was found in superficial limbal epithelial cells (six of eight eyes), the conjunctival stroma (eight of eight eyes), in the ciliary processes (three of eight eyes), and in a diffuse distribution in the region of the radial and circular muscles of the ciliary body (eight of eight eyes). In addition, TGF-beta 2 was found in the stroma adjacent to the pigmented epithelium in the pars plana (eight of eight eyes). TGF-beta 3 was found in white blood cells in one of eight specimens; otherwise it was not found in the anterior segment. The corneal stroma, corneal endothelium, trabecular meshwork, iris, and ciliary epithelia did not exhibit immunoreactivity with the antibodies used in this study., Conclusion: TGF-beta 1 and TGF-beta 2 have a distinct and specific distribution in the anterior segment of the adult human eye.

Purpose: The purpose of this study is to determine why a single intraoperative dose of mitomycin C (MMC) appears to promote the success of glaucoma filtration surgery., Methods: Human Tenon's capsule fibroblasts were exposed to MMC and 5-fluorouracil (5-FU) in vitro at the concentrations and durations of exposure used clinically. Cell proliferation was assessed by quantification of 3H-thymidine uptake. Cell viability was studied using a sulfarhodamine B cell protein stain and by trypan blue exclusion., Results: Neither MMC (0.4 mg/ml) nor 5-FU (40 mg/ml) were cytocidal. Both 1- and 5-minute exposures to MMC were antiproliferative. A 1-minute exposure to 0.4 mg/ml inhibited 3H-thymidine uptake by 77%. For the 5-minute exposure, 3H-thymidine uptake was inhibited by 50% at 0.06 mg/ml and by 90% at 0.4 mg/ml. For 5-FU, 3H-thymidine uptake was inhibited by 50% at 10 mg/ml and by 64% at 40 mg/ml., Conclusions: Mitomycin C probably does not improve the success of filtration surgery by killing fibroblasts. The ability of a brief exposure to MMC to improve filtration surgery may be due to an almost complete inhibition of proliferation. Alternatively, it may be due to sustained tissue binding, effects on other components of wound healing, such as cell migration and extracellular matrix production, or effects on the vasculature. A 1-minute exposure may be as effective as a 5-minute exposure.

Listeria monocytogenes endophthalmitis occurred in an immunologically competent patient with no identifiable extraocular septic focus. The patient presented with a dark hypopyon and markedly elevated intraocular pressure, and the diagnosis was established by culture and histopathologic examination of ocular fluid. Four of the fourteen reported cases of Listeria monocytogenes endophthalmitis also presented with a dark hypopyon, and all cases had markedly elevated intraocular pressure. The presence of a dark hypopyon and elevated intraocular pressure may indicate endogenous intraocular infection with Listeria monocytogenes, even in an apparently healthy host.

We designed and evaluated a new test for the detection of early glaucoma damage in 133 persons who were classified as normal, suspected of having glaucoma, or having glaucoma. The test stimulates the entire visual field with a flashing white light under dark-adapted conditions. It can be performed easily by a high proportion of subjects and is as reproducible as present psychophysical tests. Glaucomatous eyes were discriminated from normal with a diagnostic power of 0.91 as judged by receiver operating characteristic analysis, and specificity and sensitivity were 91% and 86%, respectively. Glaucoma suspects with an abnormal response to the whole-field scotopic test were more likely to have other signs indicating early optic nerve injury, including a greater proportion of borderline field defects, nerve fiber layer defects, or glaucomatous fellow eyes. Assessment of whole-field scotopic sensitivity may be useful in glaucoma screening.

In this study, an experimental model of glaucoma filtration surgery was used to evaluate the clinical and histologic effects of a single intraoperative topical application of mitomycin C. Argon laser treatment to the trabecular meshwork produced sustained elevation of intraocular pressure in monkeys. Eight eyes of four animals were randomly assigned to receive topical mitomycin C or balanced salt solution at the time of full-thickness sclerostomy. Surgical success was substantially increased in four of five eyes that received mitomycin C when compared with three eyes that received topical balanced salt solution. Mitomycin C was also effective in prolonging surgical success in two eyes that had previously undergone surgery and failed. No significant ocular toxicity was observed in eyes treated with mitomycin C. Histologic examination of mitomycin C-treated eyes showed patent sclerostomies and hypocellular, well-formed bleb cavities. A single intraoperative application of mitomycin C has a marked effect on postoperative wound healing after filtration surgery in monkeys.

Anterior chamber paracentesis disrupts the blood aqueous barrier (BAB) of rabbits and nonhuman primates, but the magnitude and duration of breakdown in monkeys has not been clarified. We have studied anterior chamber paracentesis in cynomolgus monkeys as a potential model of postoperative BAB breakdown. The effect of a single paracentesis upon fluorescein sodium concentration in the anterior chamber after an intravenous injection was measured in 16 eyes of 8 animals. In an additional 10 eyes of 5 animals, aqueous humor was withdrawn for analysis 24 hours and one week following paracentesis. Anterior chamber fluorescein concentration was 57 +/- 22 ng/ml (mean +/- standard deviation) before paracentesis, rose to 81 +/- 47 ng/ml 24 hrs after paracentesis, and was 60 +/- 36 ng/ml at 72-96 hours. Twenty-four hours after paracentesis, total protein concentration was elevated, but ascorbic acid and transforming growth factor-beta levels were not. Paracentesis in monkeys has only a small and short lasting effect upon BAB integrity and is therefore unlikely to be a good model for assessing the effect of agents designed to stabilize the BAB. However, the short-lived effect of paracentesis may permit the repetitive collection of "primary aqueous" for physiologic and biochemical studies.

We studied the effect of uveal pigmentation on contact Nd:YAG transscleral cyclophotocoagulation in 36 human autopsy and eight cynomolgus monkey eyes. Ten autopsy eyes from black individuals required less energy to create a lesion than 23 eyes from whites. The mean lesion diameter at the posterior pars plicata was similar in all these eyes; however, the mean energy required was 4.4 J in the black and 6.4 J in the white eyes. Transscleral cyclophotocoagulation lowered intraocular pressure (IOP) in four monkey eyes with elevated IOP, but did not in four other eyes without elevated IOP. Treatment over conjunctival pigmentation burned the conjunctiva, even at the lowest energy tested (3.5 J). Contrary to other investigators' findings, transmission electron microscopy showed at least short-term loss of scleral architecture in both the human autopsy and monkey eyes.

We have evaluated the feasibility of using polyanhydride disks containing hydrophobic antiproliferative agents for controlled drug release after glaucoma filtration surgery. Taxol and VP-16 were the most potent inhibitors of fibroblast proliferation tested, with ID50s of 3 ng/mL and 200 ng/mL, respectively. In vitro release of taxol occurred at concentrations exceeding its ID50 for at least 100 days; VP-16 was released for 31 days. The media into which the drugs were released were able to inhibit fibroblast proliferation in vitro, indicating that the bioactivity of the drugs withstood incorporation into, and release from, the polyanhydride. Polyanhydride disks containing taxol and VP-16 merit testing in animal models of glaucoma filtration surgery.

Endothelins (ETs) are a family of potent vasoactive peptides present in the eye. In the rabbit eye, both ET-1 and ET-3 are present in high concentrations in the iris and ciliary body and in lower concentrations elsewhere. Forty-eight hours after injection of 2.5 micrograms of ET-1 and ET-3 into the anterior vitreous of conscious rabbits, intraocular pressure was reduced by 43% and 45%, respectively, and did not return to normal for at least 5 days. The decrease in intraocular pressure was not due to increased aqueous outflow and was not prevented by pretreatment with indomethacin. Injection of either ET-1 or ET-3 (2.5 to 10 micrograms) into the anterior chamber or posterior vitreous cavity resulted in marked vasoconstriction, which was initiated within seconds and persisted for greater than 4 hours. Both endothelins potently constricted the pupil when added to freshly excised rabbit anterior segments. Endothelins are therefore potential participants in the local regulation of intraocular pressure, ocular blood vessel tone, and iris smooth muscle tone and may be important mediators in ocular pathologic conditions. Endothelins at pharmacologic doses may be useful in the control of intraocular pressure or blood flow.

The transforming growth factor-beta s are peptide growth factors known to play a central role in wound healing. Using a specific, in vitro assay of cell growth inhibition, we have detected transforming growth factor-beta (TGF-beta) in 24/24 aqueous humor specimens from eyes undergoing cataract extraction with intraocular lens implantation. The amount of TGF-beta ranged from 2.3 to 8.1 ng/ml (mean +/- SD = 4.5 +/- 1.7 ng/ml), with 61% present in the active form. Subtyping of TGF-beta was performed by addition of antibodies specific for the beta 1 and beta 2 isoforms to the growth inhibition assay, and confirmed with a sandwich enzyme-linked immunosorbent assay. None of the TGF-beta detected was of the beta 1 isoform; in contrast, the beta 2 isoform was present in every sample, implying that it might have originated from ocular tissues. The presence of this potent modulator of tissue repair in aqueous humor suggests a role in the healing processes following intraocular surgery, including glaucoma filtration surgery.

beta-Adrenergic antagonists taken orally adversely alter plasma lipid profiles. This study was designed to determine whether 0.5% topical timolol maleate has a similar effect. Forty volunteers who were not using medications known to alter plasma lipid levels were recruited for an unmasked study in which each subject served as his or her own control. Twelve subjects did not complete the study because of ocular and systemic side effects or extraneous factors. Twenty-eight subjects used topical timolol for an average of 76 days, with two 12-hour fasting plasma specimens obtained at the beginning and end of the period. Mean total cholesterol and low-density lipoprotein cholesterol levels did not change significantly with treatment. Triglyceride values increased 12%; high-density lipoprotein cholesterol levels decreased 9%; and the total cholesterol-high-density lipoprotein cholesterol ratio increased 8%. Higher baseline high-density lipoprotein cholesterol levels were associated with larger reductions in high-density lipoprotein cholesterol levels. Changes in high-density lipoprotein cholesterol levels of this magnitude have been estimated to increase the risk of coronary artery disease by 21%.

Successful glaucoma filtration surgery depends on the incomplete healing of the surgical wound, with formation of a filtration bleb. In most other tissues, however, complete healing is the rule. I have explored the possibility that the high concentration of ascorbic acid normally present in aqueous humor inhibits wound healing after filtration surgery. At the concentration normally present in aqueous humor (1.1 mmol/L), ascorbic acid decreased the plating efficiency of cell suspensions of human Tenon's capsule fibroblasts by a mean (+/- SD) of 40% +/- 10%. When added to low-density monolayer cultures of fibroblasts, ascorbic acid decreased the cell number by 90% +/- 5%, an effect that was completely prevented by catalase. When added to confluent cultures, the cell number was decreased by only 14% +/- 2%. If ascorbic acid has similar effects on fibroblasts in vivo, it may contribute to the incomplete wound healing that characterizes successful glaucoma surgery.

We performed filtration surgery in glaucomatous monkeys to determine if bioerodible polyanhydride disks that contained 5-fluorouridine (5-FUR) prolonged the success of the operation. First, in vitro studies demonstrated that 5-fluorouridine was released from the disks for at least 16 days in a bioactive form that inhibited fibroblast proliferation. Next, a preliminary series of six eyes suggested that using disks that contained 5-fluorouridine extended the intraocular pressure-lowering effect of filtration surgery. This finding was confirmed in eight additional eyes of four animals in which one eye received a disk with 5-fluorouridine and the other received a disk without the drug. The duration of success of the operation was significantly longer in the eyes that received polyanhydride with 5-fluorouridine (mean +/- SD, 26.0 +/- 9.2 days) than in the controls (8.5 +/- 4.0 days). The histologic findings of the experimental eyes correlated with their prolonged clinical success.

We reviewed the records of 12 eyes of ten adult patients with inflammatory glaucoma who underwent trabeculectomy with the adjuvant use of 5-fluorouracil between January 1986 and January 1989. Intraocular pressure decreased from 36 +/- 10 mm Hg (range, 17 to 50 mm Hg) preoperatively to 11 +/- 4 mm Hg (range, 3 to 17 mm Hg) postoperatively after a median follow-up of 7.75 months (range, six to 38 months). All eyes achieved an intraocular pressure of less than 20 mm Hg, and ten of 12 required no intraocular pressure lowering medications. The mean (+/- S.D.) amount of 5-fluorouracil used was 33 +/- 10 mg (range, 20 to 55 mg). During the period of observation, five of 12 eyes had an episode of uveitis, but in no patient did this result in loss of intraocular pressure control. Preoperative and postoperative systemic and topical corticosteroid use was the same. Trabeculectomy with 5-fluorouracil is an effective treatment for selected cases of adult inflammatory glaucoma refractory to medical management.

Computerized topographic mapping of 10 repeated fundus images of one eye each in 10 healthy subjects and in 10 subjects with elevated intraocular pressures (IOPs) was performed with the Humphrey Retinal Analyzer. The variability of depth measurements at 400 to 650 individual locations in the optic nerve head and peripapillary retina was evaluated. The average size of the 95% confidence intervals for individual depth measurements for healthy subjects and those with elevated IOPs were 166 and 232 microns in the optic nerve head and 205 and 261 microns in the peripapillary retina, respectively. Variability was significantly less for healthy subjects than for those with elevated IOPs. Variability was significantly greater for depth measurements in the peripapillary retina than for measurements in the optic head. Knowledge about variability of individual depth measurements is useful for proper interpretation of computerized topographic mapping to detect retinal nerve fiber damage.

We have performed a computerized analysis of postoperative changes in corneal astigmatism in 203 consecutive cases of extracapsular cataract extraction with posterior chamber intraocular lens implantation performed by one surgeon. Surgical technique was standardized consisting of a 140 degree posterior limbal incision with preplaced 9-0 silk and postplaced 10-0 nylon sutures. The average postoperative astigmatism was 1.60 D and the average surgically induced change in astigmatism 0.51 D after a mean follow-up of 5.4 months. When the axis of astigmatism was considered, cataract surgery on the average initially induced 2.2 D of with-the-rule astigmatism which gradually declined, stabilizing at 0.35 D against-the-rule 19 weeks postoperatively. An analysis of the natural history of astigmatism after cataract surgery helps to optimize the timing of spectacle prescription and postoperative intervention to correct excessive astigmatism. A computerized astigmatism analysis also provides rapid feedback to guide changes in surgical technique to minimize astigmatism.

We evaluated the reliability of optic disk area and disk rim area measurements obtained with the Humphrey Retinal Analyzer from ten repeat fundus images each of one eye of ten normal subjects and ten subjects with increased intraocular pressure. Variability of rim and disk areas was not significantly different between these two groups (P greater than .05), nor was it significantly different between images acquired during the same session and those acquired during different sessions (P greater than .05). Variability was significantly different between subject groups based on the distinctness of the disk edge and the slope of the cup wall (P less than .01). The average minimum change in the measurements on the same eye that would exceed variability of the technique at the 95% confidence level was 0.20 mm2 and 0.47 mm2 for rim area for the least variable and most variable subject groups based on optic nerve head characteristics, and 0.09 mm2 and 0.32 mm2 for disk area for the corresponding subject groups. Operator input contributed significantly to overall variability. Reliability of rim and disk areas in this study was comparable to that reported for other computerized image analyzers.

We used light microscopic autoradiography to determine the time course of cellular incorporation of tritiated thymidine (a correlate of cell division) following glaucoma filtration surgery in seven eyes of four cynomolgus monkeys with experimental glaucoma. Incorporation of tritiated thymidine was detected as early as 24 hours postoperatively. Peak incorporation occurred five days postoperatively and had returned to baseline levels by day 11. Cells incorporating tritiated thymidine included keratocytes, episcleral cells, corneal and capillary endothelial cells, and conjunctival and corneal epithelial cells. Transmission electron microscopy was correlated with the autoradiographic results to demonstrate that fibroblasts were dividing on the corneoscleral margin. These findings have potential clinical implications for the use of antiproliferative agents after filtration surgery.

Sera from patients with bullous pemphigoid (BP) contain autoantibodies that bind to the BP antigen, which is a component of the epithelial-stromal junction of the cornea. Previous studies, employing direct immunoelectron microscopy (IEM) on perilesional skin of patients have localized the BP antigen to the lamina lucida. On this basis, studies of corneal epithelial-stromal adhesion and wound healing have employed BP antigen as a marker of the lamina lucida of the corneal basement membrane zone (BMZ). The authors used indirect IEM with BP autoantibodies on frozen sections of cornea and found that the majority of the BP antigen is intracellular and is closely associated with the corneal epithelial hemidesmosome. Only a small amount of BP antigen appears to be extracellular, limited to the portion of the lamina lucida directly beneath individual hemidesmosomes. When rabbit corneal epithelium is extracted and analyzed by Western immunoblotting, BP autoantibodies recognize two polypeptides of molecular weights of 240 and 180 kilodaltons, which comigrate with BP antigens extracted from epidermis. BP autoantibodies are a specific marker of corneal epithelial hemidesmosomes and can be used as a probe to identify and study the role of hemidesmosomes in epithelial-stromal adhesion.

We have localized fibrin/fibrinogen in experimental glaucoma filtration surgery wounds in non-human primates by light and transmission electron microscopy. Fibrin/fibrinogen was abundant two days after surgery, but was virtually undetectable by seven days postoperatively. We have confirmed the identity of fibrin/fibrinogen on the ultrastructural level by immunoelectron microscopy employing antibodies directed against fibrinogen. Fibrin clot formation may play an important role in the wound healing response that causes glaucoma filtration surgery to fail.

The authors prospectively studied 67 eyes of 64 patients undergoing pars plana vitrectomy without a scleral buckle to determine the effect of surgery on postoperative corneal curvature. An average of 1 D of against-the-rule astigmatism was induced in the immediate postoperative period. This astigmatic change spontaneously regressed to less than 0.15 D by the 7th postoperative week. Pars plana vitrectomy does not induce clinically significant corneal astigmatism.

Two patients who had highly elevated pigmented masses associated with a chorioretinal scar were observed clinically for several years. The scar was due to presumed histoplasmosis in one patient and toxoplasmosis in the other. Histopathological examination disclosed choroidal and subretinal masses consisting of hyperplastic retinal pigment epithelium. The difficulty in making the diagnosis of RPE hyperplasia in such instances is discussed.

We have examined the possibility that hyperthermia, such as that occurring during fever, may benefit the immune response. The effect of temperature on the in vitro immune response of unprimed murine spleen cells against the antigen sheep erythrocytes was tested. Hyperthermia potently augmented the plaque-forming cell response. Temperature-sensitive events occurred early in the culture period. Subsets of lymphocytes were independently assessed for effects of temperature on their activation and function. We showed that the beneficial effect of elevated temperature on the plaque-forming cell response probably occurs during the priming stage of T helper cells, and neither improves the delivery of help or the activation of B cells, nor impairs suppressor T cell generation or function. We propose that this powerful immunopotentiating effect of hyperthermia may account for the selective value of the fever response. This suggests taht the monokine interleukin 1, which is the endogenous mediator of fever, may promote immune responses both through a direct action on lymphocytes, and indirectly by an action on the central nervous system resulting in fever.

We performed a double-masked, cross-over, dose-response study of apraclonidine hydrochloride (formerly known as ALO 2145) in 20 patients with elevated intraocular pressure (IOP). We administered three concentrations of apraclonidine (0.125%, 0.25%, 0.5%) and vehicle alone bilaterally every 12 hours for one week. Patients were examined 2, 5, and 8 hours after the initial dose, and then on day 2 and day 8. We studied IOP, pupillary diameter, interpalpebral fissure width, blood pressure, and pulse. There was a two-week washout period after each one-week session. All concentrations of apraclonidine significantly lowered IOP. The 0.5% and 0.25% concentrations had equal maximal effects, lowering IOP in each patient by an average of 27% relative to vehicle alone. This corresponded to a mean decrease in IOP of 8.7 mm Hg, from a baseline of 24.9 mm Hg to 16.2 mm Hg. The 0.5% and 0.25% concentrations were significantly more effective than the 0.125% concentration at two and eight hours. Mean interpalpebral fissure width increased in a dose-dependent fashion; the pupillary effect was minimal. Blood pressure and pulse were unchanged. Thirty percent of subjects reported transient dry nose or dry mouth. These symptoms may be dose-dependent.

We reviewed 100 consecutive ophthalmology consultations performed on inpatients at a large teaching hospital to help identify areas that may require greater emphasis in the medical school and housestaff curriculum. Nonophthalmologists rarely record visual acuities or perform dilated fundus examinations. If visual acuity determination were more consistently made a part of routine physical examinations, it is possible that more pathology would be detected and non-productive consultations could be minimized. We plan to emphasize these observations in our school's curriculum more than in the past.

Beta-adrenergic receptors were identified in slide-mounted sections of human trabecular meshwork by in-vitro labeling, light microscopic autoradiography. Autoradiograms were generated after incubation of slide-mounted tissue sections with 125I-cyanopindolol, a selective high-affinity probe for beta-adrenergic receptors. Experiments in which an excess of either unlabeled Practolol (beta 1 selective ligand) or Zinterol (beta 2 selective ligand) were included suggested that most of the receptors were of the beta 2 subtype. Data from displacement studies using increasing concentrations of the highly specific beta 1- and beta 2-adrenergic receptor antagonists, ICI-89,406 and ICI-118,551, respectively, confirmed the predominance of the beta 2-adrenergic receptors. Similar results obtained with cultured trabecular endothelial cells suggest that the beta-adrenergic receptors may be associated with the endothelial cells of the trabecular meshwork in vivo. These results provide anatomic evidence for the hypothesis that beta-adrenergic agents improve outflow by direct action on the trabecular meshwork and provide a rationale for the development of more selective beta 2-adrenergic agents to increase outflow facility.