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A 44-year-old man had unilateral closure of the anterior chamber angle associated with ciliary body swelling. He was treated with topical cycloplegics and corticosteroids. The shallow chamber deepended to equal the fellow eye in 6 days, and no recurrence has been noted.
INTRODUCTION: Standard filtering surgery in postoperative glaucoma in aphakic and pseudophakic eyes and eyes after failed filtering surgery is successful in 50% cases. The main cause of failure filtering surgery is scarring of the filtering bleb-fibroblastic proliferation at the subconjunctival episcleral interface [1, 2]. The use of antimetabolites such as 5-fluorouracil and Mitomycin C inhibits fibroblast proliferation and increases the success rate of filtering surgery, especially in postoperative glaucoma [3-6]. The exact dosage and frequency of administration to maximize success and minimize complications of treatment has not yet been determined [7]. METHODS: Fifteen patients (15 eyes) with medically uncontrolled postoperative glaucomas were included in the study. Clinical data are summarised in Table 1. All patients after standard trabeculectomy received 5 mg of 0.3 ml 5-fluorouracil subconjunctivally each day for 7 days. The mean 5-fluorouracil dose was 25.1 mg. Topical corticosteroid and cycloplegic eye drops were also instilled in all 15 eyes for 4 weeks after surgery. RESULTS: Successful control of IOP was achieved after a 5-fluorouracil filtering procedure in 13 of 15 eyes (86.6%), with a mean follow-up of 11.4 months. Two patients (13.4%) with uncontrolled glaucoma required cyclokryocoagulation in addition to antiglaucoma medications. Transscleral fibrosa and internal occlusive membrane were the primary cause of failure of filtration fistulas. Only one patient in the group of successful control of IOP required topical 0.5% Timolol (Table 1). Mean value of postoperative IOP was 13.53 mmHg. Most of the early complications such as corneal epitheliopathy, corneal epithelial defects and shallow anterior chamber, resolved without irreversible damage. Two eyes had transient maculopathy and choroidal detachment. There were no late complications, except progression of cataracta in one eye (Table 2). DISCUSSION: Our success rate in 5-fluorouracil treatment in postoperative glaucoma was 86.6%. The results of Fluorouracil Filtering Surgery Study Group revealed failure in 28% of eyes with 5-fluorouracil treatment compared to 60% of eyes in standard group without fluorouracil. We achieved better results in shorter follow-up. Short term complications related to 5-fluorouracil treatment such as corneal epithelipathy, recovered well with time. Long term complications caused by thin and cystic blebs: endophthalmitis, iridocyclitis, late bleb leaks, bleb encapsulated, were not recorded in our series. By comparing the results reported here with those previously reported [8-10] it looks like that certain long term complications can be reduced by adjusting the dose according to the clinical response. Weinrab et al. [10] reported similar successful surgical outcomes in refractory glaucoma, but these results cannot be compared directly, because of likely differences in such factors, as are the indications of surgical criteria for selection of specific surgical procedures, surgical technique and postoperative care. Some clinical reports have shown that Mitomycin C contributes to the increased success of filtering surgery in high risk glaucoma [11, 12], but 5-fluorouracil is still the golden standard among other antimetabolites.
Variations in response to topically applied ocular drugs (e.g. mydriatics and cycloplegics) and their possible aetiology have been studied previously. It appears that individual patient differences, external influencing factors and the characteristics of the particular drug may all govern the response. One factor worthy of note in this regard is the possibility of variation in the drug volume instilled. Single-use eye drop containers known as Minims are commonly used during ophthalmic diagnostic procedures. However, in this study the drop volume was shown to vary considerably, depending upon the angle at which the Minims container was held, the particular drug and the number of drops previously expelled from the unit.
PURPOSE: To determine the relations of corneal, lenticular and total astigmatism and the changes of the astigmatism with age. METHOD: Out-patients with refractive errors were refracted with retinoscope after using cycloplegic drops and measured the radii of anterior corneal curvature. RESULT: One hundred and ninety-four cases (382 eyes) with refractive errors were studied. Of the eyes 67.9% had regular corneal astigmatism, 68.1% irregular lenticular astigmatism and 60.7% regular total astigmatism, 88.5% of the corneal astigmatism has the same quality as the total astigmatism. The total astigmatism in 46% of the eyes included the summation of corneal and lenticular astigmatism, but in 41.3% of the eyes irregular lenticular astigmatism corrected the regular corneal astigmatism. The astigmatism of cornea, lens and total astigmatism changed from regular to irregular with the increase of age. The linear correlation analysis showed a positive correlation between the power of horizontal corneal refraction and age, and a negative corrlation between the power of vertical corneal refraction and age. CONCLUSION: The shape of cornea was the major cause of total astigmatism. The influence of lens on the total astigmatism was different. The reasons for the change of the total astigmatism from regular to irregular with the increase of age were the changes of the power of corneal refraction, particularly the increase of the power of horizontal corneal refraction and lenticular irregular astigmatism.
BACKGROUND: Excimer laser photorefractive keratectomy (PRK) is a refractive procedure to correct myopia that is gaining worldwide acceptance. PRK has been performed as an open-ended clinical trial since January 1992, and specific problems have been encountered in refracting PRK patients. METHODS: A review of all cases of PRK performed with at least 1-year follow-up was conducted. Nine hundred and seventy-one eyes with myopia ranging from -2.00 to -15.00 diopters had preoperative manifest and cycloplegic refraction, and postoperative refraction at 3 months after treatment. RESULTS: Refractive difficulty due to degradation of the retinoscopic reflex was encountered in patients who developed moderate to severe haze (seven eyes). Small ablation zones (5 mm) and decentered ablations also contributed to confusion in interpretation of the retinoscopic reflex. In addition, excessive accommodation, profound early myopic and hypermetropic shifts, postoperative irregular astigmatism and inaccurate autorefractometer readings contributed to difficulty in refraction. CONCLUSIONS: Laser ablation of the central cornea produces alterations in optical homogeneity of the cornea that may cause significant refractive difficulties. Refracting PRK patients requires careful and consistent refraction by an experienced refractionist, both before and after laser treatment.
PURPOSE: The Orinda Longitudinal Study of Myopia is a 12-year project examining predictive factors for the onset of myopia, the underlying etiologies of myopia, and normal eye growth in school children. METHODS: This paper reports on all measurements made of the ocular components (cycloplegic refractive error, corneal curvature, crystalline lens power, and axial ocular dimensions), parental history of myopia, and near work activity in children participating in the Orinda Longitudinal Study of Myopia between 1989 and 1993. An analysis of the interaction between parental history of myopia and children's near work is conducted on the cross-sectional study data from 1993. RESULTS: The cross-sectional and longitudinal data show a gradual decrease in refractive error from low hyperopia toward emmetropia, no shift in corneal curvature, a gradual decrease in crystalline lens power, thinning of the crystalline lens, and elongation of the eye between the ages of 6 and 14 years. Parental history is more contributory to a statistical model predicting myopia than is near work, but near work is a significant factor as well. We can find no evidence of statistical interaction between parental history and near work in explaining the presence or absence of myopia. CONCLUSIONS: The emmetropization process is evident in the gradual decrease in refractive error toward emmetropia, the axial elongation of the eye, and the compensating decrease in crystalline lens power. Both nature and nurture play a role in the etiology of myopia, although the predominant role appears to belong to a positive parental history of myopia. This role does not appear to be through an interaction between parental myopia status and children's near work activity.
UNLABELLED: The aim of our study is estimation of the efficacy of recombinant tissue plasminogen activator for the treatment of fibrinous membranes following cataract extraction. PATIENTS AND METHODS: The fibrinous membranes were formed, despite conventional antiinflammatory therapy, in 17 eyes after ECCE with IOL and in 3 eyes after ECCE without IOL. We injected the solution of recombinant tissue plasminogen activator-Actilyse (Boehringer Ingelheim) into the anterior chamber of 20 eyes after cataract surgery. Simultaneously, topical corticosteroid and cycloplegic therapy was continued. Routine follow-up included slit lamp examination, ophthalmoscopy and intraocular pressure measurement. RESULTS: Injection of the solution of tissue plasminogen activator into anterior chamber of 20 eyes resulted in complete dissolution of the fibrinous membranes in 18 eyes within 1 day. In 7 eyes, within a few days after injection, fibrinous membrane recurred. In four of this cases durable effect of fibrin dissolution was obtained after multiple tPA injections. Finally, expectable stable result was obtained in 15 of 20 eyes. CONCLUSIONS: Results of our study confirm high efficacy of recombinant tissue plasminogen activator in the treatment of fibrinous membranes after cataract surgery. Short term follow-up and small number of cases motivates further continuation of observation.
We have observed 22 patients with angle-closure glaucoma following scleral buckling operations. These patients did not have narrow anterior chamber angles preoperatively, and several were aphakix with surgical iris colobomas. The angle-closure glaucoma was manifest by a hazy cornea, elevated intraocular pressure, closed angle, absence or iris bombé, and presence of choroidal detachments. Treatment with cycloplegics and corticosteroids was more effective than treatment with miotics. A likely pathogenic mechanism is congestion and swelling of the ciliary body due to a temporary interference by the scleral buckle with venous drainage. Episcleral implants accounted for a statistically significant higher incidence of angle-closure glaucoma as compared to intrascleral implants.
PURPOSE: To document the development of key optical and structural parameters of the crystalline lens throughout childhood and examine possible mechanisms by which lens power remains coordinated with the growth of the eye to maintain emmetropia. METHODS: Using cycloplegic autorefraction, video-based phakometry, and ultrasonography, the authors measured refractive error and crystalline lens parameters in 994 children in the first through eighth grades, who participated in the Orinda Longitudinal Study of Myopia, between one and five times from 1989 through 1993. Polynomial growth curves were fit to the data by maximum likelihood estimation. The average annual rates of change in each parameter from each subject's longitudinal data were also estimated. RESULTS: The lens radii of curvature flattened throughout childhood, yet decreases in lens equivalent power stopped after 10 years of age. This indicates that the refractive index of the lens increased during later childhood. Lens thinning in early childhood also ceased after 10 years of age. The spherical volume of the lens showed no appreciable net increase, but the axial length of the eye continued to grow throughout childhood. The prevalence of myopia in our data increased sharply at age 10 years, reaching 21.3% by the age of 14 years. CONCLUSIONS: Concurrent thinning and flattening of the crystalline lens imply that the lens is mechanically stretched by the equatorial growth of the eye during childhood. Changes in the patterns of lens development near the age of 10 years, concurrent with the onset of myopia, suggest that forces arise which interfere with equatorial growth. Such forces might diminish the decreases in lens power and amplify axial elongation to promote myopia.
In oculocutaneous albinism (OCA), one can distinguish between a tyrosinase-negative form (no residual activity of the enzyme tyrosinase) and a tyrosinase-positive form (with detectable residual enzymatic activity) and their respective subtypes. In infancy and early childhood the clinical discrimination between tyrosinase-positive OCA and tyrosinase-negative OCA can be very difficult. To date, only the hair-bulb L-dopa incubation test has been helpful in discriminating between the tyrosinase (ty)-negative and ty-positive forms of OCA. In 68 patients with albinism of the eye, 24 had an oculocutaneous form of albinism. We determined the ty relationship either by the L-dopa incubation test (younger patients) or by clinical appearance (older patients). We determined the full cycloplegic refraction in all patients and looked for a possible correlation of the refraction with the ty relationship. Our data suggest that an OCA patient with a hyperopic refractive error of > 4.0 D might have a ty-positive form of OCA. A patient with a moderate to high degree of myopia is more likely to have a ty-negative form of OCA. Determination of ty relationship is more reliable in patients with high degrees of hyperopia and, therefore, in patients with a ty-positive form of OCA. Statistical evaluation of the data was not possible in a sensible way due to the small number of patients involved in the present study.
A 68-year-old diabetic Pakistani presented with a 3 year history of progressive bilateral painless loss of vision. Although he was previously untreated for glaucoma, his examination revealed the following: visual acuity, finger counting in the right eye and 20/60 in the left; intraocular pressure (IOP), 41 and 31 mm Hg, respectively. Physical findings included bilateral shallow anterior chambers, minimal nuclear and cortical cataract formation, and extensive glaucomatous optic nerve cupping and atrophy worse in the right eye than in the left. Gonioscopy revealed angles narrowed to grade 1 for 360 degrees in both eyes. Visual field analysis was commensurate with the marked degree of optic nerve damage and reduced visual acuity. Bilateral laser iridotomies and a combination of topical antiglaucoma agents reduced IOP to the mid-20s in both eyes. Subsequently, the right eye had an uneventful trabeculectomy with application of intraoperative mitomycin. Postoperatively, the patient developed posterior aqueous entrapment and was managed with topical cycloplegics, aqueous suppressants, and corticosteroids. After a few weeks, a shallow anterior chamber was present centrally, a filtration bleb was noted, and IOP was 9 mm Hg. Unexpectedly, the patient returned to his native country, discontinued medications, and was lost to follow-up for 1 year. Upon his return, he presented with these findings: visual acuity, hand motion in the right eye and 20/60 in the left eye; IOP, 10 and 30 mm Hg, respectively. Physical findings in the right eye (Figure 1) included a superiorly oriented, thin-walled filtration bleb, a formed anterior chamber with multiple broad peripheral and midperipheral synechias, and a bound pupil covering a dense nuclear sclerotic cataract. The left eye had progressive glaucomatous optic nerve changes. Given the patient's history, now would you manage the glaucoma in the left eye, and what surgical methods would you plan for the right eye, assuming cataract surgery is indicated?
BACKGROUND: High astigmatism is frequently associated with congenital ptosis. Ptosis surgery itself may also induce astigmatic refractive change that will cause amblyopia in young children. The purpose of this study was to assess postoperative astigmatic change and the effect of different ptosis surgical procedures on astigmatism. METHODS: An analysis of 63 consecutive surgical cases of congenital ptosis was conducted. The preoperative incidences of anisometropia, amblyopia, strabismus and high astigmatism were evaluated. All patients underwent levator resection or received frontalis sling. The postoperative astigmatic change after the follow-up period of 12 months was assessed in 28 patients. It included a total of 40 ptotic eyelids from 12 bilateral and 16 unilateral cases of ptosis. The eyes on the contralateral side in unilateral cases served as the control group. RESULTS: In 63 cases of congenital ptosis, 30.2% (19/63) were associated with anisometropia and 39.7% (25/63) with amblyopia, and 11.1% (7/63) were combined with strabismus. Most cases of amblyopia were associated with high astigmatism (64%). The incidence of high astigmatism (> 2.5 diopters, D) in congenital ptosis was 25.3%. Of 40 ptotic eyelids included for the study of postoperative astigmatism change, 15% showed an increase of more than 0.5 D, whereas 27.5% showed a decrease of more than 0.5 D, and no significant change was observed in 57.5%. An average decrease of 0.18 D in astigmatism was observed, while no statistical difference was found between the study group and the control group for astigmatic change. Moreover, both the levator resection and frontalis sling groups showed a decrease in average cylinder, and again, demonstrated no statistically significant difference in astigmatic change. CONCLUSIONS: A high incidence of amblyopia was associated with astigmatism in congenital ptosis. Postoperative astigmatic study also revealed some change in astigmatic power, but no new cases of amblyopia developed after ptosis surgery. Patients with congenital ptosis should have cycloplegic refraction as soon as possible, and long-term postoperative refraction check-up is also recommended.
PURPOSE: To provide baseline measurements on the postnatal changes in refractive error, corneal curvature, and axial elongation of the eyes of normal monkeys. Little is known about the course of normal eye growth from birth to adolescence, particularly how refractive parameters co-vary during development. In animal models of ametropia, usually one eye is manipulated and the fellow eye serves as a control. However, given individual differences, and without baseline data, it is impossible to determine whether either eye develops normally. METHODS: Measurements were obtained on 237 rhesus monkeys, whose ages ranged from birth to 5 years. Examinations included cycloplegic refraction by retinoscopy, keratometry measurements, and A-scan ultrasound measurements of axial length. The time course of development was evaluated using a growth curve analysis appropriate for a mixture of cross-sectional and longitudinal data. RESULTS: At birth, all three parameters were normally distributed and only weakly correlated. Monkeys had +7 D (SD=2.3 D) of hyperopia, corneal power of 58 D (SD=1 D), and axial length of 13.2 mm (SD=0.4 mm). Refractive error ranged from +0.5 D to +14.5 D, with a mean difference between the two eyes of 0.5 D. Corneal curvature ranged from 61 D to 54 D, with a mean difference between the two eyes of 0.8 D. Axial length ranged from 12.0 mm to 14.2 mm, with a mean difference between the two eyes of 0.1 mm. Although the degree of hyperopia achieved asymptote, of + 2 D, shortly after 1 year of age, corneal curvature and axial length did not achieve asymptote until nearly 5 years of age. By this time, refractive error had declined by 5 D, corneal curvature had declined by 7 D, and axial length had increased by 6 mm. CONCLUSIONS: The magnitude of the individual differences that can occur in a small sample of experimental subjects is large enough to necessitate reference to age norms derived from a large population. Our results provide a baseline for studies of normal and abnormal eye growth and ametropia in primates. Our results also led to the confirmation of a set of "rules" that have been offered as an explanation of how these three parameters interact during emmetropization.
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