Corticosteroid-induced ocular hypertension. II. An acquired form.

Thirty-five patients with unilateral closed-angle glaucoma treated by peripheral iridectomy and prophylactic peripheral iridectomy in the fellow eyes were subjected to corticosteroid provocative test in both eyes. 51% of the eyes with closed-angle glaucoma and 11% of their fellow eyes had a positive corticosteroid pressure response. The closed-angle glaucoma eyes had their fellow eyes responded differently as shown by the frequency distribution graphs and also by the difference between the corticosteroid-induced change in pressure (Wilcoxon test, z=-4.80, p less than 0.0001). These results provide evidence for an acquired form of corticosteroid-induced ocular hypertension and the possible pathogenic factors for the first time. The clinical significance of an acquired form of corticosteroid-induced ocular hypertension is discussed.     

The prevalence of diabetes mellitus in the family history of patients with primary glaucoma

The prevalence of diabetes mellitus in the family history of 371 patients with primary glaucoma - closed-angle glaucoma, ocular hypertension and open-angle glaucoma - and 85 age- and sex-matched control subjects was determined. There was a significantly-increased prevalence of familial type 2 diabetes mellitus (non-insulin dependent diabetes mellitus) in patients with closed-angle glaucoma (p = 0.004) and ocular hypertension (p = 0.02). Primary glaucoma was not associated with familial type 1 diabetes mellitus (insulin dependent diabetes mellitus). The implications are discussed.     

Corticosteroid-induced ocular hypertension. I. Prevalence in closed-angle glaucoma.

Forty-eight eyes with closed-angle glaucoma and 31 eyes at risk were subjected to corticosteroid provocative tests. 65% and 9.7% respectively responded with a change in pressure greater than or equal to 6 mmHg. The responses of the 2 groups were compared with each other and also with the corticosteroid pressure response in normal eyes. The differences in behaviour between the eyes with closed-angle glaucoma and eyes at risk, and the eyes with closed-angle glaucoma and normal eyes, are statistically highly significant. The implication of this are discussed. The prevalence of corticosteroid-induced ocular hypertension in closed-angle glaucoma is higher than previously reported.     

Atenolol versus propranolol. A comparison of ocular hypotensive effect of an oral dose.

In a controlled double-blind cross-over trial in 10 patients comprising six with open-angle glaucoma, three with closed-angle glaucoma, and one with ocular hypertension, a single oral dose of atenolol (50 mg) was significantly more effective than propranolol (40 mg) in reducing ocular tension.     

The fellow eye.

The result of a 10-year longitudinal study of the fellow eye at risk of developing closed-angle glaucoma (because the presenting eye had the disease) is described. 202 eyes were observed between 1 August 1970 and 31 July 1980. Each eye was provoked shortly after presentation using a pilocarpine phenylephrine provocative test. If the test produced a closed-angle glaucoma an iridectomy was done; if closed-angle glaucoma did not occur the eye was observed and it was reprovoked at yearly intervals. There were 3 possible outcomes for any one eye. Either the eye developed closed-angle glaucoma; or it was lost to follow-up; or at the end of the study the patient was alive, under observation, without having developed glaucoma. 90% of acute attacks occurred within 6 months of presentation. If an eye survived the first year without getting glaucoma the probability of its development in any one year period up to the fifth anniversary was 0.05; thereafter it was zero. The cumulative probability of an eye surviving to the fifth anniversary without glaucoma was 0.34, remaining constant thereafter; that is 34% of iridectomies are unnecessary. A high prevalence of ocular hypertension was seen in eyes that did not have an iridectomy (26%). It was concluded that a routine iridectomy is not necessary and that the fellow eye that will get glaucoma can usually be detected. The untreated fellow eye presents a naturally occurring model of one of the mechanisms involved in the production of ocular hypertension.     

急性闭角型青光眼患者血浆心钠素含量及临床意义

报告22例急性闭角型青光眼患者血浆心钠素含量明显高于正常对照组。提示我们血浆心钠素水平的改变是眼局部病变与机体应激性保护反应的结果,与青光眼病是否存在某种联系有待进一步探讨。     

Pupil cycle time in primary closed-angle glaucoma

Pupil cycle time was measured in fellow eyes of 118 patients with closed-angle glaucoma and 70 age- and sex-matched control subjects. Results indicate that the duration of pupil cycle time was significantly prolonged in patients with closed-angle glaucoma as compared to the control group (p less than 0.001); in addition, the prevalence of absent pupillary oscillation was significantly increased in closed-angle glaucoma patients (p less than 0.001). The implications are discussed, with particular reference to the association between closed-angle glaucoma and systemic parasympathetic neuropathy.     

应用彩色多普勒血流动力学检查对多种青光眼的观察

目的　应用彩色多普勒血流成像技术观察多种青光眼血流动力学变化。方法　应用彩色多普勒诊断仪测量正常眼和多种青光眼的眼动脉、睫状后动脉、视网膜中央动脉的血流动力学指标。结果　原发性开角型青光眼组、原发性慢性闭角型青光眼组、青光眼睫状体炎综合征组阻力指数显著增高 ,与正常组对照均有显著性差异 (P<0 .0 5 ) ,高眼压征组无显著性差异 (P>0 .0 5 ) ;各组血流速度降低 ,以舒张末期血流速度降低明显 (P<0 .0 5 ) ;各组搏动指数无显著性差异 (P>0 .0 5 )。结论　局部血流障碍可能是引起青光眼视功能损害的一个重要因素 ,阻力指数、血流速度特别是舒张末期血流速率可作为青光眼血流动力学检测的可靠指标     

Provocative tests in closed-angle glaucoma.

Altogether 119 eyes at risk of developing closed-angle glaucoma were provoked with simultaneous pilocarpine and phenylephrine; of these 74 developed closed-angle glaucoma. The remaining 45 eyes were re-provoked with tropicamide and a further nine developed closed-angle glaucoma. The 36 eyes in which all tests were negative were given no treatment and have been observed for a period of 1 to 7 years (mean 3 years). One has developed closed-angle glaucoma. A scheme for provoking eyes at risk of developing closed-angle glaucoma is described.     

Acute closed-angle glaucoma after arteriovenous fistulas

Unilateral secondary acute closed-angle glaucoma was associated with a ciliochoroidal detachment in two patients. One patient, aged 17 years, had an orbital arteriovenous fistula. The other patient, aged 73 years, had a dural arteriovenous fistula that originated from branches of the right internal maxillary artery. In each patient there was increased intraocular pressure, a moderately shallow central anterior chamber, and a flat peripheral anterior chamber. The ciliochoroidal detachment was postulated to displace the iris-lens diaphragm, resulting in the closed angle. Closure of the orbital fistula in the 17-year-old patient reduced the ciliochoroidal detachment and relieved the glaucoma, but visual acuity was reduced to 20/200. The glaucoma in the 73-year-old patient was relieved with topical instillation of timolol 0.5%, homatropine 5%, and systemic administration of acetazolamide. The fistula closed spontaneously, with relief of other ocular signs of the arteriovenous fistula.     

Non-steroidal drug-induced glaucoma

Numerous systemically used drugs are involved in drug-induced glaucoma. Most reported cases of non-steroidal drug-induced glaucoma are closed-angle glaucoma (CAG). Indeed, many routinely used drugs that have sympathomimetic or parasympatholytic properties can cause pupillary block CAG in individuals with narrow iridocorneal angle. The resulting acute glaucoma occurs much more commonly unilaterally and only rarely bilaterally. CAG secondary to sulfa drugs is a bilateral non-pupillary block type and is due to forward movement of iris-lens diaphragm, which occurs in individuals with narrow or open iridocorneal angle. A few agents, including antineoplastics, may induce open-angle glaucoma. In conclusion, the majority of cases with glaucoma secondary to non-steroidal medications are of the pupillary block closed-angle type and preventable if the at-risk patients are recognized and treated prophylactically.     

MASS SCREENING OF THE OPTIC DISC FOR GLAUCOMA: A FOLLOW-UP STUDY

Because of the high false positive and negative rates for detection of suspects when screening for glaucoma by tonometry, we screened 12 156 subjects over the age of 40 years or with a stated family history of glaucoma by examining the optic discs. This was followed by Schiotz tonometry. Eight hundred and twelve (6.7%) suspects were referred to their primary physician for investigation by an ophthalmologist. A database program was used to send out follow-up letters to both suspects and ophthalmologists. Three hundred and seventynine replies were received from ophthalmologists: 100 (26.4%) of these suspects had ocular hypertension and 68 (17.9%) had glaucoma. Of these 68, 60 (15.8%) had chronic simple glaucoma, five (1.3%) had secondary open-angle glaucoma, and three (0.79%) had primary closed-angle glaucoma. The prevalence of all types of glaucoma in this group for which follow-up was obtained was at least 0.56% of the total number screened. Assuming that the prevalence was similar for the group for whom no replies were obtained, the prevalence of glaucoma in this population is approximately 1.19%. Screening by optic disc examination is therefore likely to detect most cases of glaucoma.     

Timolol in operated closed-angle glaucoma.

Tonometry in 9 eyes (7 patients) provides some evidence that timolol eye drops are useful in improving control of pressure in eyes operated for closed-angle glaucoma. In cases 1 and 2 (Figs, 1 and 2) this beta 1 and 2 blocker reduced pressure consistently. Case 3 (Fig. 3) showed that timolol 0.5% twice daily was as effective as pilocarpine 2% or 4% with adrenaline 1%. The effect of timolol 0.5% in case 4 (Fig. 4) and case 6 (Fig. 6) was additive to pilocarpine and adrenaline; in case 5 (Fig. 5) it probably improved the effect of adrenaline, but in cases 4 and 5 there may have been some loss of effect with time. Case 7 (Fig. 7) showed a good effect of timolol, reversed on withdrawal, but pressure fell again in spite of continued withholding of timolol. Timolol will be especially valuable in the control of pressure if an operation involving iridectomy has not been completely successful in open-angle glaucoma or more especially in closed-angle glaucoma because it has no effect on the pupil. Miotics will tend to produce posterior pupillary synechiae because aqueous humour will go through the iridectomy, not under the edge of the pupil. The danger will be greater in eyes with closed-angle glaucoma because the pupil is closely applied to the anterior lens surface, which will also tend to produce irritative iridocyclitis.     

Drugs and closed-angle glaucoma risk

Closed-angle glaucomas arise among predisposed patients (narrow iridocorneal angle) in response to various stimuli. Most of the attacks are of iatrogenic origin: all the topical and systemic mydriatic drugs can provoke an angle closure glaucoma attack. Dangerous active ingredients with closed-angle glaucoma are active substances with anticholinergic activity (peripheral action, central action, with anticholinergic side-effects), active ingredients with sympathomimetic alpha activity (alpha 1, alpha and beta with indirect effects), and the active ingredients with parasympathomimetic activity (anticholinesterases). The proprietary medicine, whether or not they are included in the French dictionary Vidal((R)), are classified according to the administration route and their different indications. The closed-angle glaucoma risk after administration of these drugs is noted in the items'contraindications and precautions in the summary of the product characteristics enclosed in the marketing authorization.     

Emergencies in glaucoma: a review

Most severe eye diseases and injuries ultimately require intervention by an ophthalmologist. The urgency of referral depends on various factors, including level of vision loss, duration of symptoms, and presence of comorbid diseases. Of special importance are five acute eye problems in which emergency management by primary care physicians can be critical to visual outcome: high-velocity injuries, chemical injuries, acute angle-closure glaucoma, arteritic ischemic optic neuropathy, and central retinal artery occlusion. This paper will focus on emergencies in glaucoma, especially primary and secondary closed-angle glaucoma and secondary open-angle glaucoma. Delay in presentation, and unresponsiveness to medical treatment of the acute ocular hypertension attack carry a significant risk of chronic glaucoma, whatever the mechanism of disease is. Whenever the acute glaucoma crisis does not cease with an appropriate medical treatment, a laser and/or surgical intervention needs to be urged.     

Closed-angle glaucoma in 20 pairs of twins

Two pairs of twins with chronic closed-angle glaucoma identified from the Finnish Twin Cohort Study were clinically studied by the author, and 18 other pairs of twins with the disease were ascertained from the Hospital Discharge Registry of Finland. One of the clinically studied pairs was a pair of monozygotic female twins concordant for chronic closed-angle glaucoma and the other was a pair of dizygotic female twins discordant for the disease. Of the pairs of twins ascertained from the registry one was a monozygotic male pair concordant for closed-angle glaucoma. The remaining 17 pairs (12 same-sex dizygotic and 5 monozygotic pairs) were discordant for the disease. The findings support multifactorial inheritance of chronic closed-angle glaucoma.     

Mass screening of the optic disc for glaucoma: a follow-up study

Because of the high false positive and negative rates for detection of suspects when screening for glaucoma by tonometry, we screened 12 156 subjects over the age of 40 years or with a stated family history of glaucoma by examining the optic discs. This was followed by Schiotz tonometry. Eight hundred and twelve (6.7%) suspects were referred to their primary physician for investigation by an ophthalmologists. A database program was used to send out follow-up letters to both suspects and ophthalmologists. Three hundred and seventy-nine replies were received from ophthalmologists: 100 (26.4%) of these suspects had ocular hypertension and 68 (17.9%) had glaucoma. Of these 68, 60 (15.8%) had chronic simple glaucoma, five (1.3%) had secondary open-angle glaucoma, and three (0.79%) had primary closed-angle glaucoma. The prevalence of all types of glaucoma in this group for which follow-up was obtained was at least 0.56% of the total number screened. Assuming that the prevalence was similar for the group for whom no replies were obtained, the prevalence of glaucoma in this population is approximately 1.19%. Screening by optic disc examination is therefore likely to detect most cases of glaucoma.     

Dilating dangerous pupils.

Altogether 85 eyes from patients at risk to the development of closed-angle glaucoma were dilated with either parasympatholytic or sympathomimetic drugs. Of 21 eyes dilated with cyclopentolate 1/2%, 9 developed angle closure and a significantly raised pressure at some stage during dilatation and subsequent miosis. Of 58 eyes dilated with tropicamide 1/2%, 19 developed angle closure and a significantly raised pressure during dilatation. Treatment with intravenous acetazolamide and pilocarpine rapidly returned pressure to normal levels. Six eyes that had previously had a positive provocative test with simultaneous pilocarpine and phenylephrine were safely dilated with phenylephrine alone. Subsequent miosis with pilocarpine produced closed-angle glaucoma in all eyes. The significance of these observations is explained and discussed, and it is suggested that high-risk eyes should never be dilated with cyclopentolate. Tropicamide is safe if elementary precautions are observed. Safest of all, however, is phenylephrine-induced mydriasis and subsequent miosis with thymoxamine drops 1/2%.     

Thymoxamine reverses phenylephrine-induced mydriasis

We performed a randomized double-masked evaluation of the alpha-adrenergic blocking agent thymoxamine (0.1%) as compared to placebo for the reversal of phenylephrine-induced mydriasis. Topically applied thymoxamine reversed the mydriasis from a single drop of 2.5% phenylephrine in 36 of 40 eyes (90%) within one hour. The mydriasis was completely reversed in 25 of 40 eyes (63%). Eyes with blue irides responded more quickly and more completely than did those with brown irides. The 40 contralateral eyes, which had also been dilated with phenylephrine, remained dilated or dilated further after receiving a placebo eyedrop. Twenty subjects (50%) reported mild transient ocular irritation upon instillation of thymoxamine. Thymoxamine was useful in individuals with narrow anterior chamber angles who were at risk of acute closed-angle glaucoma following dilation with an adrenergic agent.