A limited comparison of apraclonidine's dose response in subjects with normal or increased intraocular pressure

We performed a multicentered, placebo-controlled, randomized, crossover study comparing the efficacy of 0.5% and 1.0% apraclonidine hydrochloride in 15 normal volunteers and 17 subjects with increased intraocular pressure. Apraclonidine 1% produced a maximum 30.4% +/- 14.0% (4.7 +/- 2.4 mm Hg) decrease in mean intraocular pressure in normal eyes and a 31.3% +/- 16.5% (7.6 +/- 4.2 mm Hg) decrease in eyes with increased pressure. Apraclonidine 0.5% produced a maximum 25.8% +/- 9.7% (4.0 +/- 1.7 mm Hg) decrease in mean intraocular pressure in normal eyes and a 27.4% +/- 16.0% (6.8 +/- 4.5 mm Hg) decrease in eyes with increased pressure. There was no statistically significant difference in mean percent intraocular pressure lowering effect between the 0.5% and 1.0% apraclonidine concentrations. Most subjects treated with apraclonidine had a greater than or equal to 20% reduction in intraocular pressure from baseline. Twelve hours after instillation of apraclonidine, nine of the normal volunteers had an intraocular pressure of 10 mm Hg or less. Apraclonidine produced the same percent intraocular pressure decrease regardless of the initial level of intraocular pressure.     

Clinical assessment of long-term safety and efficacy of a widely implanted polyacrylic intraocular lens material

PURPOSE: To evaluate the long-term safety and efficacy, in a large series of patients, of polyacrylic intraocular lens implants 1 and 3 years after surgery, compared with polymethylmethacrylate intraocular lens implants. METHODS: This was a randomized, prospective study of 1,514 eyes of 1,202 patients that were examined for a 1-year follow-up study and 1,264 eyes of 990 patients that were examined for a 3-year follow-up study. All the patients were prospectively randomized to receive a polyacrylic or polymethylmethacrylate intraocular lens implant. A standardized surgical protocol was performed using a phacoemulsification technique and capsulorhexis. Any surgical complications were excluded, and all patients had standard postoperative medication and follow-up. Postoperative measurements included spectacle-corrected visual acuity, occurrence of postoperative sight-threatening or lens-related complications, and adverse reactions. Results were compared between the polyacrylic intraocular lens and polymethylmethacrylate intraocular lens groups. Results were also compared with standards for polymethylmethacrylate intraocular lens that were established by the US Food and Drug Administration and a previous study for silicone lens. RESULTS: The overall complete follow-up rates were 79.9% for 1-year follow-up and 69.5% for 3-year follow-up. At 1 year, the mean logarithm of the minimum angle of resolution (logMAR) of visual acuity was 0.037 +/- 0.150 and 0.042 +/- 0.154 in best case patients of the polyacrylic intraocular lens group and polymethylmethacrylate intraocular lens group, respectively. At 3 years, the mean logMAR visual acuity was 0.038 +/- 0.155 and 0.054 +/- 0.181 in best case patients in the polyacrylic intraocular lens group and polymethylmethacrylate intraocular lens group. There was no significant difference between groups at 1 and 3 years. At 1 year, 96.8% of best case patients in the polyacrylic intraocular lens group and 95.8% of those in the polymethylmethacrylate intraocular lens group achieved corrected visual acuity of 0.5 or better. At 3 years, 96.4% of best case patients in the polyacrylic intraocular lens group and 94.9% of those in the polymethylmethacrylate group achieved a corrected visual acuity of 0.5 or better; no significant difference was found at 1 and 3 years. The rate of sight-threatening complications was 1. 2% for the polyacrylic intraocular lens group of all patients and 1. 5% for the polymethylmethacrylate intraocular lens group at 1 year, and 1.6% for the polyacrylic intraocular lens group and 1.4% for the polymethylmethacrylate intraocular lens group at 3 years. No significant difference was found between the groups. The cumulative rate of Nd:YAG capsulotomy for the polyacrylic intraocular lens group (7.1%) was significantly lower than that for the polymethylmethacrylate intraocular lens group (38.1%) through 3 years (P <.0001). CONCLUSIONS: Polyacrylic intraocular lenses demonstrated safe and effective performance through long-term follow-up at a level equal to or better than polymethylmethacrylate intraocular lenses. Patients undergoing polyacrylic intraocular lens implantation achieved excellent postoperative visual acuity and experienced a low rate of postoperative complications, adverse reactions, and Nd:YAG capsulotomy. These long-term clinical results are an important outcome database for the ongoing use of this foldable optic material.     

Predictive value of a 1-day, 1-eye trial on the 1-month ocular hypotensive response of latanoprost 0.005%

PURPOSE: To determine if a 1-day, 1-eye trial of latanoprost 0.005% was predictive of the 1-month intraocular pressure response in patients with uncontrolled open-angle glaucoma on maximally tolerated medical therapy without latanoprost. METHODS: One eye of 39 consecutive patients was enrolled in prospective trial of latanoprost 0.005%. An investigator masked to treatment eye and intraocular pressure result measured intraocular pressure at 1 day and 1 month after treatment. The diagnostic precision of the 1-day, 1-eye trial for the 1-month result was determined at a 10%, 20%, and 30% reduction from baseline intraocular pressure. RESULTS: Treatment produced a mean +/- SD (range) decrease in intraocular pressure from 20.9 +/- 4.6 (14 to 35) mm Hg to 16.6 +/- 3.6 (9 to 26) mm Hg at 24 hours (P <.0001, paired t test). This reduction in intraocular pressure was similar at 1 month with mean +/- SD (range) intraocular pressure of 16.1 +/- 3.1 (9 to 22) mm Hg (P <.0001, paired t test). The accuracy of the 1-day, 1-eye trial for the 1-month response at a 10%, 20%, and 30% reduction of intraocular pressure from baseline intraocular pressure was 96% (chi square = 29.5, P <.001), 74% (chi square = 8.4, P =.004), and 80% (chi square = 10.2, P =.001), respectively. CONCLUSION: A 1-day, 1-eye trial of latanoprost 0.005% is predictive of the 1-month intraocular pressure response in patients with uncontrolled open-angle glaucoma.     

人工晶状体脱位49例临床分析

目的 探讨人工晶状体（IOL）脱位的临床特点。 设计 回顾性病例系列。 研究对象  北京同仁医院2004-2011年治疗的IOL脱位 49例49眼。 方法 对IOL脱位患者的临床资料进行回顾性分析。 主要指标 年龄、原IOL植入原因,发病时间,脱位IOL位置及类型,IOL脱位诱因,手术治疗方法及并发症。 结果  49眼IOL脱位中,老年性白内障和外伤性白内障摘除联合IOL植入术者较多,分别占46.9%、28.6%。6例睫状沟固定IOL脱位均发生于手术1年后。脱位IOL53.1%位于玻璃体腔内。89.8%为C形襻IOL。IOL脱位75.5%由原眼部因素及手术因素引起。47眼（95.9%）实施 了IOL睫状沟缝线固定或再次缝线固定术治疗,术后2周裸眼视力0.1以上者占59.6%。结论   IOL脱位的发生与原眼部因素及手术因素有关。睫状沟缝线固定IOL术是治疗IOL脱位的有效手段,但睫状沟固定的IOL仍会发生脱位。（眼科,2012,21：47-51）     

Comparison of the ocular effects of topical etomidate and pilocarpine in rabbits

Etomidate, (R-(+) ethyl-1-(phenylethyl) 1H-imidazole-5-carboxylate), when administered as drops to the eyes of normal New Zealand white rabbits in concentrations of 2%, 4% and 8% in arachis oil has been shown to significantly lower the intraocular pressure in these animals. The intraocular pressure was measured with the Perkins handheld applanation tonometer.The intraocular pressure reducing effect of the 2% and 4% were better than that of 1% pilocarpine; the two per cent etomidate solution reduced intraocular pressure from a pretreatment mean of 13.6mm Hg to a new mean of 7.7mm Hg after three weeks treatment, while the 4% etomidate solution lowered the intraocular pressure from a pretreatment mean of 14.4mm Hg to a new mean of 7.3mm Hg also after three weeks treatment. Pilocarpine (1%) reduced the intraocular pressure from a pretreatment mean of 13.7mm Hg to 10.7mmHg after three weeks treatment in the same group of rabbits. Etomidate (8%) solution also showed a more significant reduction of intraocular pressure than the 2% solution of pilocarpine. The eight percent etomidate reduced the pretreatment mean intraocular pressure of 14.0mm Hg to a new mean of 6.5mm Hg after three weeks treatment while 2% pilocarpine lowered a pretreatment mean of 13.9mm Hg to 9.0mm Hg after three weeks treatment in the same group of rabbits.There was a persistence of the low intraocular pressure produced by the various concentrations of etomidate in arachis oil after treatment with these drops was stopped. However, this feature was also shown by the two concentrations of pilocarpine used but not in as marked an extent as the etomidate solutions with regard to duration of effect and height of reduction of the intraocular pressure.During a three week period of topical application of drops to the rabbits eyes, the etomidate solutions were found to have no effect in the iris sphincter.     

Effect of calcium channel blockers alone and in combination with antiglaucoma medications on intraocular pressure in the primate eye

PURPOSE: To determine the effect of representative members from six classes of calcium channel blockers on intraocular pressure in the primate eye. Other antiglaucoma medications were administered with verapamil to determine their combined effect on intraocular pressure. METHODS: Six healthy cynomolgus monkeys were anesthetized, and baseline intraocular pressure was measured. Drug-containing solution (50 microL) was instilled in one eye and intraocular pressure was measured in both eyes 90 minutes later. RESULTS: All classes of calcium channel blockers significantly lowered intraocular pressure in the treated eye. The percent reduction in intraocular pressure compared with the baseline pressure was 10% for verapamil (P < 0.002), 18% for nifedipine (P < 0.001), 15% for diltiazem (P < 0.001), 17% for flunarizine (P < 0.001), 19% for prenylamine (P < 0.001), and 6% for perhexiline (P < 0.01). In the fellow eye, a significant reduction in intraocular pressure was also seen with all calcium channel blockers except perhexiline, which suggested a crossover effect. In contrast, neither vehicle treated nor contralateral eyes showed a lowering of intraocular pressure when tested under the same conditions. In the treated eye, 0.5% timolol (P < 0.01) and 0.05% clonidine (P < 0.02) combined with 0.25% verapamil each appeared to produce an additive effect, with a significantly greater pressure-lowering effect than either agent alone. In addition, 0.005% pilocarpine (P < 0.001) and 0.00125% demecarium (P < 0.01) combined with 0.25% verapamil each appeared to produce a synergistic effect, with a significantly greater reduction in intraocular pressure than both agents combined. CONCLUSIONS: Topical calcium channel blockers and combinations of verapamil with antiglaucoma medications may provide a useful alternative for reducing intraocular pressure in patients with ocular hypertension or primary open-angle glaucoma.     

Pharmacological testing in the laser-induced monkey glaucoma model

Glaucoma was induced in cynomolgus monkeys by photocoagulating the trabecular meshwork with the argon laser. Repeat treatments were often necessary and wide intraocular pressure fluctuations were characteristic. Baseline intraocular pressure was measured with a calibrated pneumatonometer hourly for six hours. On a succeeding day a baseline measurement was made, 50 microliter of the drug to be tested applied, and six hourly measurements of intraocular pressure repeated. The effects on intraocular pressure of timolol, epinephrine, pilocarpine, vanadate, prostaglandin F2 alpha (PGF2 alpha), forskolin, and corynanthine were tested in at least eight eyes. Significant (p less than 0.05) reductions of intraocular pressure were produced by 0.5% timolol, 2% epinephrine, 4% pilocarpine, 1% vanadate, 500 micrograms of PGF2 alpha and 1% forskolin. Five per cent corynanthine produced no significant lowering of intraocular pressure. Tonography revealed an increased outflow facility associated with the reduction of intraocular pressure 2 hours after the administration of 4% pilocarpine. This glaucoma animal model may be useful in investigating agents that lower intraocular pressure by a variety of mechanisms.     

An optical model to describe image contrast with bifocal intraocular lenses

We attempted to quantify the decrease in contrast associated with the concentric-style bifocal intraocular lens by using a model eye and bifocal intraocular lens, with a model unifocal intraocular lens as a control. When imaging near objects, pupils smaller than 2.5 mm produced image contrast of 100% of the control; larger pupils degraded contrast to 25% for a 6-mm pupil. For distant objects, pupils smaller than 2.5 mm produced image contrast of 70% to 95% because of the pinhole effect; larger pupils engaged the distance portion of the intraocular lens and maintain 80% contrast on average. Thus, the bifocal intraocular lens produced image contrast greater than 70% in all situations tested, except when imaging near objects with a pupil larger than 3.5 mm. The data suggest that image contrast is highly dependent on pupil size and object distance.     

A study of the effects of four concentrations of D-timolol, 0.25% L-timolol, and placebo on intraocular pressure on patients with raised intraocular pressure.

The intraocular pressure lowering effect in 30 patients with raised intraocular pressure and open angles following a single application in a randomised double-masked fashion of four concentrations of D-timolol (0.25%, 0.5%, 1.0%, and 2.0%), 0.25% L-timolol, and placebo are presented. The percentage reduction in intraocular pressure after four hours following single-drop instillation range from 20% to 25% in the D-timolol group, 32% in the L-timolol group, and only 8% in the placebo group of treated eyes.     

Comparison of clinical outcomes between iris-fixated anterior chamber intraocular lenses and scleral-fixated posterior chamber intraocular lenses in Marfan syndrome with lens subluxation

Background: To compare the clinical outcomes in Marfan's with subluxated lens having phaco‐emulsification with simultaneous scleral‐fixated posterior chamber intraocular lens or iris‐fixated anterior chamber intraocular lens implantation. Design: Randomized case series in the State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat‐sen University, Guangzhou, China. Participants: Seventy‐one eyes of 49 patients with Marfan syndrome with subluxated lens. Methods: This is a randomized case series of patients with Marfan syndrome and subluxated lenses who underwent phaco‐emulsification combined with scleral‐fixated posterior chamber intraocular lens or iris‐fixated anterior chamber intraocular lens implantation. Main Outcome Measures: The evaluation indexes included the surgery time, best corrected visual acuity, intraocular pressure, aqueous flare and cells counts, corneal endothelium counts and complications. Results: Increase in best corrected visual acuity in both groups was not significant. The aqueous flare and cells rose in both groups postoperatively. Significant difference between the two groups at 1 week postoperatively was found, whereas no statistically significant difference was found later. The loss rate of corneal endothelium cells in the scleral‐fixated posterior chamber intraocular lens group was 13.2% and 19.5% at 3 months and 1 year postoperatively, which in the iris‐fixated anterior chamber intraocular lens group was 13.3% and 19.3% (P > 0.05). Prolapse of vitreous was found in 21 cases intraoperatively. The posterior capsule opacification rate was 32% and 15%, respectively. The decentration of the intraocular lens was found in 19 eyes (48.7%) in the scleral‐fixated posterior chamber intraocular lens group 1 year postoperatively, whereas none was found in the iris‐fixated anterior chamber intraocular lens group. Conclusions: Iris‐fixated anterior chamber intraocular lens after phaco‐emulsification presented a safe, simple and efficient approach for managing subluxated lens in Marfan syndrome.     

Intraocular pressure changes and postural changes of intraocular pressure in experimentally induced Hansen''s disease of rhesus, mangabey, and African green monkeys.

In our long term evaluation of patients with Hansen's disease we have frequently found reduction of their intraocular pressure. Furthermore, we noted changes in their intraocular pressure on change of posture. To determine if these changes have any significance we measured the intraocular pressures of 24 experimentally infected and 39 control monkeys in both sitting and reclining positions. We found significant reduction of intraocular pressure in 66.7% compared with controls in the sitting position, and a significant increase in intraocular pressure in 79% when checked first in the sitting then in the reclining position. We offer a possible pathophysiological explanation as to why the changes occur.     

Contralateral effect of topical beta-adrenergic antagonists in initial one-eyed trials in the ocular hypertension treatment study

PURPOSE: To evaluate the magnitude of the contralateral effect of topically administered beta-blockers on intraocular pressure. METHODS: The Ocular Hypertension Treatment Study enrolled 1,636 subjects. Of these, 817 subjects were randomized to receive topical ocular hypotensive medication and 819 subjects were randomized to close observation (i.e., no topical medication). We compared the intraocular pressure of the contralateral eye of subjects at the baseline visit and after an initial one-eyed therapeutic trial of topical beta-blockers. We examined differences between baseline and follow-up intraocular pressure in untreated eyes of subjects randomized to close observation. RESULTS: The mean reduction in intraocular pressure in the beta-blocker-treated eyes was -5.9 +/- 3. 4 mm Hg (-22% +/- 12%; Student t test, P <.0001). In the contralateral eyes, mean intraocular pressure reduction was -1.5 +/- 3.0 mm Hg (-5.8% +/- 12%; P <.0001). Of the contralateral eyes, 35% showed a reduction of 3 mm Hg or more, and 10% showed a reduction of 6 mm Hg or more. The contralateral effect of the relatively selective beta-blocker betaxolol did not differ from that of any of the nonselective beta-blockers. Factors associated with the magnitude of the contralateral effect were the degree of intraocular pressure reduction in the treated eye and baseline intraocular pressure of the contralateral eye. In the close observation group, no significant reduction in intraocular pressure was noted between the baseline and follow-up visit. CONCLUSIONS: The contralateral effect is important in clinical practice and in clinical trials when the hypotensive effect of a topical beta-blocker is evaluated by means of a one-eyed therapeutic trial.     

Acute primary angle-closure: long-term intraocular pressure outcome in Asian eyes

PURPOSE: To report the long-term outcome of intraocular pressure after laser peripheral iridotomy in Asian eyes with acute primary angle-closure. METHODS: Retrospective study of 111 eyes of 96 consecutive patients with acute primary angle-closure, presenting at the National University Hospital, Singapore, from 1990 to 1994. The presenting features of the affected eye and the treatment instituted were recorded. The subsequent long-term intraocular pressure outcome was analyzed. An increase in intraocular pressure on follow-up was defined as increase in intraocular pressure greater than 21 mm Hg and requiring treatment by medication or surgery. RESULTS: The mean follow-up period was 50.3 months (range, 9 to 107 months). The mean presenting intraocular pressure was 52.8 mm Hg (range, 28 to 80 mm Hg). One hundred ten eyes were treated with laser peripheral iridotomy, with resolution of the acute episode and intraocular pressure less than 21 mm Hg in all eyes after laser peripheral iridotomy. Of these, only 46 eyes (41.8%) were successfully treated with laser peripheral iridotomy alone in the long term. Sixty-four eyes (58.1%) developed an increase in intraocular pressure (requiring treatment) on follow-up, of which 49 eyes developed an increase in intraocular pressure within the first 6 months after acute primary angle-closure. Thirty-six eyes (32.7%) eventually underwent trabeculectomy because of uncontrolled intraocular pressure despite laser and medical therapy. CONCLUSIONS: In this study of Asian eyes, a high proportion (58.1%) of eyes with acute primary angle-closure developed an increase in intraocular pressure on long-term follow-up after resolution of the acute attack, despite the presence of a patent laser peripheral iridotomy. These results suggest a racial difference in the outcome of laser peripheral iridotomy after acute primary angle-closure in Asians, compared with Caucasians. Because a majority of eyes that develop an increase in intraocular pressure do so within the first 6 months of presentation, close monitoring of intraocular pressure is advised in the follow-up of patients with acute primary angle-closure.     

Development of experimental chronic intraocular hypertension in the rabbit.

There are many unanswered questions about chronic glaucoma which cannot be investigated in the available animal models. The present experiments were designed to develop a rabbit model of chronic intraocular hypertension with characteristics similar to human chronic glaucoma by ligating vortex veins or by making single or multiple intraocular injections of 0.5% or 1% alpha-chymotrypsin, 20% chondroitin sulphate, 2% hydroxypropyl methylcellulose, 2% sodium carboxymethylcellulose or 1% or 2% methylcellulose. Evaluation was based on the clinical findings, intraocular pressure and the retrograde axoplasmic transport function of the optic nerve using a horseradish peroxidase histochemical technique. Most methods either failed to produce moderate chronic intraocular hypertension or were associated with other complications. However, a reliable and relatively long period (eight weeks) of intraocular hypertension was developed by a series of four intra-anterior chamber injections of 1% or 2% methylcellulose. This model has been proved suitable for the study of structural and functional damage to the retina and optic nerve caused by chronic glaucoma.     

Management of increased intraocular pressure after cataract extraction

We measured the change in intraocular pressure prospectively after extracapsular cataract extraction in 80 eyes after treatment with either pilocarpine gel, pilocarpine 4% solution, timolol 0.5% solution, or placebo. Intraocular pressure, pupil size, and anterior chamber cellular reaction were measured in a masked fashion on the first day after surgery. A significant increase in intraocular pressure was found in all groups postoperatively when compared with baseline values (P less than .001). Eyes treated with pilocarpine gel had an average intraocular pressure increase of 4.2 +/- 2.1 mm Hg (mean +/- 1 S.E.), eyes treated with pilocarpine 4% eyedrops had an average increase of 9.8 +/- 2.8 mm Hg, and eyes treated with timolol demonstrated an intraocular pressure increase of 8.25 +/- 3.19. The intraocular pressure in untreated eyes (controls) increased by an average of 12.9 +/- 2.7 mm Hg. Only the difference in intraocular pressure change between the eyes treated with pilocarpine gel and control eyes was statistically significant (P = .025). Postsurgical intraocular pressure exceeding 25 mm Hg was observed in three of 20 pilocarpine gel treated eyes (15%) and 11 of 20 control eyes (55%). Pilocarpine treatment was not associated with noticeable changes in intraocular inflammatory response, nor were significant ocular or systemic adverse reactions observed. A single administration of pilocarpine gel is effective in reducing increased intraocular pressure for the first 24 hours after extracapsular cataract extraction.     

Intraocular anti-Toxoplasma gondii IgA antibody production in patients with ocular toxoplasmosis

PURPOSE: To investigate the immunoglobulin classes associated with the intraocular anti-Toxoplasma gondii antibody response during clinical ocular toxoplasmosis and to determine which immunoglobulin class is most helpful in the diagnosis of this disease. METHODS: Paired serum and intraocular fluid samples from 155 patients who had uveitis were tested for intraocular anti-T. gondii IgG, IgA, and IgM antibody production. The presence of T. gondii DNA was determined by polymerase chain reaction. Patients were divided into two groups, based on the initial clinical diagnosis; group 1 included 78 patients with presumed ocular toxoplasmosis, and group 2 included 77 patients with uveitis that was not clinically suspected to be ocular toxoplasmosis. Samples from 27 nonuveitis patients who underwent intraocular surgery were used as control subjects. The final diagnosis was based on the clinical course and interpretation of laboratory tests. RESULTS: A final diagnosis of ocular toxoplasmosis was made in 88 of 155 patients (group 1, 68; group 2, 20). Among these patients, 65% had intraocular IgG production, 52% had intraocular IgA production, 37.5% had both IgG and IgA production, 27% had IgG production only, and 15% had IgA production only. Of the 13 patients tested, only one had intraocular IgM production. Intraocular IgA could not be detected in patients who had final diagnoses other than ocular toxoplasmosis or in control subjects. A positive polymerase chain reaction combined with a test that was positive for intraocular IgG production had a sensitivity of 77%, which increased to 91% after the detection of intraocular IgA production was added. CONCLUSIONS: Immunoglobulin G is the major class involved in the humoral immune response against the T. gondii parasite, followed by IgA. The determination of IgA production is useful as an additional test in the diagnosis of ocular toxoplasmosis.     

Long-term intraocular pressure-lowering efficacy and safety of timolol maleate gel-forming solution 0.5% compared with Timoptic XE 0.5% in a 12-month study

PURPOSE: To evaluate the long-term intraocular pressure-lowering efficacy and safety of timolol maleate gel-forming solution 0.5% (Timolol GFS 0.5%, Alcon Research Ltd, Fort Worth, Texas) compared with Timoptic XE 0.5% (Merck, Inc, West Point, Pennsylvania) in patients with open-angle glaucoma or ocular hypertension. METHODS: Two hundred forty-one patients with open-angle glaucoma or ocular hypertension, who had intraocular pressure between 22 and 36 mm Hg in at least one eye, were randomly assigned in a 2:1 ratio to receive either Timolol GFS 0.5% once daily or Timoptic XE 0.5% once daily, in a 12-month randomized, multicenter, double-masked, prospective study. The primary efficacy variable was mean trough intraocular pressure measured at 8:00 AM, approximately 24 hours after dosing. RESULTS: The Timolol GFS 0.5% group produced significant trough intraocular pressure reductions from a baseline of 4.5 to 5.2 mm Hg (P =.0001), compared with reductions of 4.1 to 5. 3 mm Hg (P =.0001) in the Timoptic XE 0.5% group. The difference in mean intraocular pressure between the two treatments was 0.9 mm Hg or less, and the upper 95% confidence limit between groups was 0.92 mm Hg or less at all time points, demonstrating both clinical and statistical equivalence. A similar percentage of patients in the Timolol GFS 0.5% group (71%) and Timoptic XE group (72%) had clinically relevant reductions in intraocular pressure. There was no significant difference in the safety profiles of the two treatments. CONCLUSION: Both treatments were clinically effective in lowering intraocular pressure and maintaining the reductions over long-term use. Timolol GFS 0.5% is a safe and effective therapy for open-angle glaucoma or ocular hypertension and is both clinically and statistically equivalent to Timoptic XE 0.5% in reducing intraocular pressure.     

A STUDY OF THE INTRAOCULAR PRESSURE LOWERING EFFECT OF TIMOLOL AND DIPIVALYL EPINEPHRINE

A double masked cross-over study was carried out to compare the intraocular pressure lowering effect of Timolol maleate 0.25% and Dipivalyl epinephrine (DPE) 0.1% eye drops. Timolol showed a greater effect in reducing intraocular pressure, with a mean reduction of 8.0 mm/Hg than did DPE, with a mean reduction of intraocular pressure of 4.3 mm/Hg.     

Development of experimental chronic intraocular hypertension in the rabbit

There are many unanswered questions about chronic glaucoma which cannot be investigated in the available animal models. The present experiments were designed to develop a rabbit model of chronic intraocular hypertension with characteristics similar to human chronic glaucoma by ligating vortex veins or by making single or multiple intraocular injections of 0.5% or 1%α-chymotrypsin, 20% chondroitin sulphate, 2% hydroxypropyl methylcellulose, 2% sodium carboxymethylcellulose or 1% or 2% methylcellulose. Evaluation was based on the clinical findings, intraocular pressure and the retrograde axoplasmic transport function of the optic nerve using a horseradish peroxidase histochemical technique. Most methods either failed to produce moderate chronic intraocular hypertension or were associated with other complications. However, a reliable and relatively long period (eight weeks) of intraocular hypertension was developed by a series of four intra-anteriar chamber injections of 1% or 2% methylcellulose. This model has been proved suitable for the study of structural and functional damage to the retina and optic nerve caused by chronic glaucoma.     

玻璃体视网膜术后高眼压临床分析及治疗

目的 探讨玻璃体视网膜术后高眼压的发病率、相关危险因素及治疗方法.方法 采用前瞻性临床研究,对112例玻璃体视网膜术后患者进行随访,采用非接触眼压计测量术前、术后7d、2周、1月眼压,对高眼压患者进行药物治疗、前房穿刺或手术治疗.结果 术后26例(23.2%)发生高眼压.术中行硅油填充、C3F8填充术后高眼压发病率为23.8%,23.5%.行巩膜环扎和未行巩膜环扎术后高眼压发病率为33.3%,21.6%.术中行晶体摘除和未行晶体摘除高眼压发病率为28.5%,19.6%.PVRC2及以上组和PVRC2以下组高眼压发病率为35.1%,15.9%.高眼压多发生于术后1周内,占80.8%.1周后出现高眼压为5例,占19.2%.高眼压持续时间1d,2d,3d和1周以下,1周以上各为30.8%,23.1%,11.5%和88.5%,11.5%.经logistic回归分析高眼压的危险因素为合并外伤、糖尿病、PVR、眼内手术史、术中联合环扎、眼内填充.结论 眼压升高是玻璃体切除手术后常见并发症,危险因素有外伤、糖尿病、PVR、眼内手术史、术中联合环扎、眼内填充.药物治疗和前房穿刺可有效降低眼压.

Abstract：

Objective To investigate the incidence,risk factors and treatments of intraocular pressure elevation following vitreoretinal surgery.Methods A total of 112 patients who underwent vitreoretinal surgery were prospectively observed.IOPs were measured before surgery and at lweek (everyday),2 weeks,1 month after surgery with non-touch tonometry examination.The patients with intraocular pressure elevation were treated by medication,anterior chamber paracentesis and surgery.Results The IOP elevation occurred in 26patients after operation (23.2%).The rate of IOP elevation with intraocular tamponade of C3F8 or silicone oil was 23.8% or 23.5%.The rate of IOP elevation in sclera buckling was 33.3% and 21.6% for no sclera buckling.The rate of IOP elevation in aphakia was 28.5% and 19.6% for phakia.The rate of IOP elevation in patients with proliferative vitreoretinopathy (PVR) ≥ gradeC2 was 35.1% and 15.9 % for ≤ gradeC2.The IOP elevation occurred mostly within 1 week (80.8%).Through the logistic regression analysis,the risk factors of IOP elevation include trauma,diabetes,proliferative vitreoretinopathy,intraocular surgery history,sclera buckling and intraocular tamponade.Conclusions IOP elevation is a common complication of vitreoretinal surgery.The risk factors of ocular hypertension include trauma,diabetes,proliferative vitreoretinopathy,intraocular surgery history,sclera buckling and intraocular tamponade.Most ocular hypertension following vitreoretinal surgery can be effectively treated by medication and anterior chamber paracentesis.