TWO YEARS' EXPERIENCE WITH LASER TRABECULOPLASTY

A series of 115 argon laser trabeculoplasties on 109 eyes in 84 patients over a two-year period is reviewed. Control of glaucoma was achieved in 85%. There was correlation of a greater fall in intraocular pressure with initial height of intraocular pressure and degree of pigmentation of the angle. Gonioplasty proved an effective means of treating cases with a narrowed angle to gain access to the trabecular meshwork.     

LASER TRABECULOTOMY OR TRABECULOPLASTY: EARLY EXPERIENCE WITH A NEW NON-INVASIVE SURGICAL TECHNIQUE FOR GLAUCOMA

A series of 38 laser trabeculoplasty operations in 32 eyes of 29 patients is described. An average fall of 5.32 mmHg intraocular pressure was obtained; if secondary glaucomas were excluded the average fall was 7.39 mmHg. If a fall of 10 mmHg or more is considered a good result then eight eyes obtained a good result, five of these eyes having pseudoexfoliative glaucoma. A fall of 3–9 mmHg was considered a moderate result and 12 eyes obtained this, 11 of them having chronic simple open-angle glaucoma, the other being the only other case of pseudoexfoliative glaucoma in the series. Five eyes with chronic simple open-angle glaucoma and seven eyes with secondary glaucoma all obtained no significant fall. It is stressed that in chronic simple open-angle glaucoma there was often only a small fall or no fall at all, so that it seems unwise to temporise if there is a high uncontrolled pressure in this condition. Great care is also needed in advanced chronic simple open-angle glaucoma because of the occasional occurrence of a high rise of pressure soon after operation. The procedure works well in pseudoexfoliative glaucoma.     

ARGON LASER TRABECULOPLASTY AND THE OPEN-ANGLE GLAUCOMAS

Argon laser trabeculoplasty (ALT) was used to treat 237 eyes of 156 presurgicalpatients with various open-angle glaucomas. Patients with primary open-angle glaucoma formed the largest group; intraocular pressure (IOP) control judged clinically to be adequate was achieved in 77.3% of eyes. Eyes with pseudoexfoliative glaucoma demonstrated the greatest IOP reduction achieving control in 90.7%. Eyes with combined-mechanism glaucoma underwent argon laser iridectomy prior to ALT. One month after ALT the IOP was considered adequate in 70% of eyes. ALT may benefit eyes with low-tension glaucoma, pigmentary glaucoma and aphakic open-angle glaucoma. Treatment failures were frequent in eyes with angle recession and uveitis. Complications included IOP elevation (7.8%) and mild iritis; technique modifications minimized their frequency and intensity. ALT demonstrated an excellent benefit-to-risk ratio. Its effect additive to medications, ALT often permitted a reduction in the medical regimen, but rarely cessation of drug therapy. ALT is recommended as an alternative to drainage surgery.     

ARGON LASER TRABECULOPLASTY FIVE YEARS ON

The results of argon laser trabeculoplasty (ALT) in a series of 252 patients are presented with follow-up of up to five years. The procedure is effective in chronic open-angle glaucoma (COAG), ocular hypertension and pseudoexfoliative (PXF) glaucoma. Most cases were treated initially over 180° of the angle and repeat treatment of the remaining 180° usually resulted in an additional fall in IOP which was maintained at two, three and four year follow-up with only a small number of these retreated cases having no fall on later follow-up. ALT was not very effective in further lowering IOP in eyes with IOP controlled to a low level before treatment or in low tension glaucoma. It was effective in most of a number of miscellaneous glaucomas including pigmentary glaucoma. Apart from the immediate high rise in IOP the main complication was a late high rise in IOP which was serious in degree and appeared mainly in PXF but also in two cases of ocular hypertension. The presence of a concomitant fall in IOP in the fellow untreated eye is important and probably due to better compliance with treatment. Almost all cases required medical treatment for glaucoma which could not be ceased after ALT. ALT should be seen as an adjunct to, but not a substitute for, medical treatment.     

DO ANY FACTORS PREDICT A FAVOURABLE RESPONSE TO LASER TRABECULOPLASTY?

One hundred and thirty-three eyes with raised intraocular pressure treated by argon laser trabeculoplasty were studied to determine the factors predicting a fall in pressure with treatment. The two main predictive factors were: (i) initial pressure—a higher initial pressure was associated with a greater fall in pressure (p < 0.001); and (ii) diagnosis (type of glaucoma)—pseudoexfoliative glaucoma (PXFG) and chronic open-angle glaucoma (COAG) had the greatest fall (p < 0.05). Aphakic glaucoma was associated with the worst results. Of the other factors studied, only the degree of pigmentation of the angle was a significant predictor: the greatest fall in pressure occurred in eyes with moderately pigmented angles (p = 0.05). Complications of treatment were pigment scatter in the angle with depigmentation (41% of eyes), peripheral anterior synechiae (7.5%), immediate postoperative rise in pressure of 10 mmHg or more (7%), moderately severe iritis (3%) and hyphaema (2%). Medication was able to be ceased in only five patients after laser trabeculoplasty; even if a small fall in pressure is achieved, a large fall to the bottom of the normal range is unlikely.     

氩激光小梁成形术联合房角成形术治疗慢性闭角青光眼的临床研究

用氩激光小梁成形术联合房角成形术治疗慢性闭角青光眼13例15眼(大多属晚期病例),随访5～7月,平均眼压下降1.62kPa,64.3%的治疗眼眼压低于2.79kPa,且房角普遍增宽,视力及视野无恶化者,随访期间未发现严重并发症,表明该治疗方法是可行的。     

PREVENTING A HIGH RISE IN INTRAOCULAR PRESSURE AFTER LASER TRABECULOPLASTY

The high rise in pressure which sometimes follows laser trabeculoplasty is a serious and sight-threatening complication in patients with advanced glaucoma. In a previous study we found that patients undergoing laser trabeculoplasty were very unlikely to have a high rise in pressure if the initial pressure was less than 20 mmHg. In the present study a series of patients was given acetazolamide 500 mg immediately before laser trabeculoplasty if their pressures were greater than 20 mmHg. All patients were then monitored to see if this regime was effective in preventing a serious rise in intraocular pressure. Some of the patients with an initial pressure less than 20 mmHg still sustained a high rise in pressure after laser trabeculoplasty. A further series of patients was then given acetazolamide preoperatively and the postoperative rise in pressure was monitored two and 24 hours after trabeculoplasty. The acetazolamide prevented a high rise in pressure after laser trabeculoplasty in the majority of patients .     

THE DETECTION AND MANAGEMENT OF THE ACUTE RISE IN INTRAOCULAR PRESSURE FOLLOWING LASER TRABECULOPLASTY

A series of 64 patients undergoing laser trabeculoplasty had pressures estimated immediately before treatment and at one, two and three hours and in some patients at four, 24 and 48 hours after treatment. Pilocarpine 4% was given topically to 33 patients in order to assess its effect in preventing a pressure rise. The mean pressure rise for the whole series was 4 mmHg, for those not using pilocarpine it was 4.9 mmHg, and for those using pilocarpine it was 3.2 mmHg. A significant pressure rise of 5 mmHg or more was usually apparent by two hours, and patients with no rise or a fall at two hours were very unlikely to develop a rise in pressure.
Patients with an initial pressure greater than 20 mmHg, pseudoexfoliation of the lens capsule, and a shallow anterior chamber seemed more susceptible to a pressure rise while those with an initial pressure of 17 mmHg or less and only a slight reaction in the anterior chamber seemed very unlikely to develop a pressure rise. Treatment with acetazolamide, fluorometholone drops and hypotensive drops was usually successful in controlling the raised pressure.     

The effect of topical corticosteroids on laser-induced peripheral anterior synechiae

Purpose : To assess the influence of different topical steroid agents and a non-corticosteroid medication after Argon laser trabeculoplasty (ALT) on the development of peripheral anterior synechiae (PAS) and the reduction of intraocular pressure (IOP).
Method : In two separate prospective, randomised, group-controlled studies, topical fluorometholone 0.1% (FML Liquifilm) was compared with dexamethasone 0.1% (Maxidex) (Study A), or naphazoline hydrochloride 0.1% (Albalon) (Study 6) after ALT for chronic open-angle glaucoma, with particular reference to the formation of PAS and the IOP response.
Results : In Study A ( N =109) eyes treated with Maxidex had a significantly higher incidence of PAS than those treated with FML—45% compared with 22%, P <0.05 (normal deviate test).
In Study B ( N =75) the incidence of PAS was equal in eyes treated with FML or Albalon (23%).
In the two studies combined ( N =184), the development of PAS was associated with a significantly lower mean response of IOP to ALT—1.47 mmHg compared with 3.22 mmHg, 0.01< P <0.05 (Student t -test).
Conclusion : The incidence of PAS after ALT is significantly higher with the post-laser use of Maxidex than with FML, and is the same for Albalon as for FML. The therapeutic benefit of ALT is significantly reduced if PAS develop.     

LASER TRABECULOPLASTY AND ITS EFFECT ON TONOGRAPHY, CENTRAL VISUAL FIELDS, AND ANTERIOR CHAMBER DEPTH. A PRELIMINARY STUDY

A preliminary study of ten patients with glaucoma, each of whom has undergone laser trabeculoplasty to one or both eyes, is presented. Tonography-on-treatment was performed on each patient approximately four weeks prior to laser, and repeated approximately ten weeks afterwards. Central fields and anterior chamber depth measurements before and after laser trabeculoplasty are also presented.
Intraocular pressures fell by a mean of 12.34 mm (SD±8.5, range 3–23) in all 12 lasered eyes. Central fields improved in ten eyes, and the anterior chamber of treated eyes became shallower by an average of 0.27 mm, compared with untreated eyes ( p <0.05). Po/C values improved in 11 treated eyes. Very little attempt was made to alter medical treatment during the period outlined above.     

A review of argon and selective laser trabeculoplasty as primary treatments of open-angle glaucoma

It is generally accepted within the ophthalmic community that medical therapy is the preferred primary treatment in open-angle glaucoma, followed by laser trabeculoplasty if the medical therapy is unsuccessful, with surgery employed more as an end-stage option when these avenues have been exhausted. This review discusses the efficacy of argon laser trabeculoplasty, alone and in comparison with medical therapy as a primary treatment of glaucoma. It will also discuss the new laser technique, selective laser trabeculoplasty.     

Diode laser trabeculoplasty

Diode laser is a solid state Gallium Aluminium Arsenide (Ga AIAs) laser with a wavelength of approximately 800 nm (near infrared radiation). It has a similar penetration to, and absorption within the ocular tissues as, Krypton red. Diode laser trabeculoplasty (DLT) was carried out on 20 glaucomatous eyes resulting in a mean fall in intraocular pressure of 6.35 mmHg at one month and 6.45 mmHg at three months. Over this early period DLT has an effect similar to argon laser trabeculoplasty (ALT) in the management of open-angle glaucoma.     

SELECTIVE LASER TRABECULOPLASTY: A NEW APPROACH TO OPEN ANGLE GLAUCOMA MANAGEMENT

Selective Laser Trabeculoplasty (SLT) is a new treatment modality for lowering Intra-ocular pressure (IOP). It targets the pig-mented cells of the trabecular meshwork (TM) with minimal damage to TM architecture. It is safe, effective & warrants consideration as a primary treatment. Purpose: 1 .To investigate the safety & efficacy of new laser procedure using q-switched     

Increased risk of open-angle glaucoma following chronic rhinosinusitis: a population-based matched-cohort study

Purpose

Anatomically, the eyes and paranasal sinuses are neighboring structures and some studies have mentioned eye disease in conjunction with chronic rhinosinusitis (CRS). However, to the best of our knowledge, no prior research has investigated the risk of developing open-angle glaucoma (OAG) among CRS patients. This study aims to provide an estimated risk of developing OAG among patients with CRS by using a population-based data set in Taiwan.

Methods

This retrospective cohort study used data sourced from the ‘Longitudinal Health Insurance Database 2000''. A total of 15 642 CRS patients were included in the study cohort and 46 926 subjects were randomly extracted as a comparison cohort. A cox proportional-hazards regression analysis was performed to calculate the 5-year risk of subsequently developing OAG following a diagnosis of CRS between the study cohort and the comparison cohort.

Results

The incidence rate of developing OAG over the 5-year follow-up period was 5.45 (95% CI: 4.95–5.98) per 1000 person-years for the study cohort and 2.80 (95% CI: 2.60–3.03) per 1000 person-years for the comparison cohort. After censoring the cases that died over the 5-year period and adjusting for the factors of monthly income, geographic region, hypertension, diabetes, coronary heart disease, hyperlipidemia, and hypothyroidism the hazard ratio for developing OAG over the 5-year period for subjects with CRS to subjects without CRS was 1.73 (95% CI: 1.53–1.96).

Conclusion

We found that those subjects with CRS had a significantly higher risk of developing OAG over the 5-year follow-up period as compared with subjects without CRS.     

EXPERIENCE WITH DIPIVALYL EPINEPHRINE: ITS EFFECTIVENESS, ALONE OR IN COMBINATION, AND ITS SIDE EFFECTS

Dipivalyl epinephrine was as effective as adrenaline as an eyedrop for glaucoma. It was responsible for fewer side effects, though side effects did occur. It had an additive effect when used with timolol maleate and. in 12 of 14 patients on long-term medication with both drugs, a rise of pressure of 3 mmHg or more occurred when dipivalyl epinephrine was stopped. As sole therapy dipivalyl epinephrine was effective in chronic simple open-angle glaucoma, ocular hypertension and pseudoexfoliative glaucoma, and may be useful on its own in the latter two conditions. In low-tension glaucoma it seemed the best therapy when combined with timolol. Headache and ocular pain were uncommon but prominent side effects.     

Micropulse laser for the treatment of glaucoma: A literature review

Glaucoma, a progressive optic neuropathy, is the leading cause of irreversible blindness worldwide. Glaucoma patients are usually initially managed with medications and laser therapies, before more invasive ocular surgeries. For laser treatments of glaucoma, laser trabeculoplasty and laser transscleral cyclophotocoagulation lower the intraocular pressure by increasing the aqueous outflow and decreasing the aqueous production, respectively. The development of a subthreshold laser technique, the micropulse laser, has been investigated as a potential alternative to traditional glaucoma laser procedures, with an aim to further decrease the risk of side effects without compromising the laser treatments' efficacy. Few reviews have been done on the 2 current micropulse laser treatments for glaucoma—micropulse laser trabeculoplasty and micropulse transscleral cyclophotocoagulation. Hence, the purpose of this review was to assess the efficacy and safety of micropulse laser techniques in the treatment of glaucoma.     

Relationship between systemic hypertension,perfusion pressure and glaucoma: A comparative study in an adult Indian population

Aims:

To study the relationship between blood pressure (BP), intraocular pressure (IOP), mean ocular perfusion pressure (MOPP) and primary open angle glaucoma (POAG) in patients with hypertension and compare it to a control group of normotensives.

Design:

Cross-sectional observational study.

Materials and Methods:

A total of 108 subjects with primary hypertension and 100 age-matched controls without hypertension were enrolled for the study. IOP measurement using Noncontact Tonometer and dilated fundus evaluation using + 90 D lens were done for all cases. Single recording of BP was taken. Gonioscopy, Humphrey''s central visual fields, optical coherence tomography and pachymetry were done for all subjects with IOP > 21 mm Hg or C: D ratio ≥ 0.5 or asymmetry of > 0.2.

Statistical Analysis:

Univariate and multivariate multinomial regression models were used to determine the association between covariates and risk of glaucoma or glaucoma suspect.

Results:

There was no difference in the glaucoma status between subjects with and without hypertension. Subjects on antihypertensive medications were 1½ times more likely to have suspicious glaucoma (odds ratio [OR] =1.56] and nearly twice as likely to have POAG (OR = 1.85). In addition, we found a 31% and 12% reduction in risk of having POAG (95% confidence interval [CI] =13–45%, P = 0.001) and glaucoma suspect (95% CI = 2–21%, P = 0.03) respectively with every 1 mm Hg increment in MOPP.

Conclusion:

Subjects on antihypertensive medications are more likely to have either glaucoma or glaucoma suspect, and higher ocular perfusion pressure offers relative protection from glaucomatous damage.     

Microinvasive glaucoma surgery: A review of 3476 eyes

Microinvasive glaucoma surgery (MIGS) is a potentially safer and more efficacious method studied in patients with mild-to-moderate open-angle glaucoma requiring less invasive treatment goals; however, the literature on MIGS must be thoroughly evaluated. We conducted a review of MIGS by searching MEDLINE, EMBASE, and Cochrane CENTRAL. Primary efficacy indicators were reductions in intraocular pressure and topical medication use postoperatively. While all comparative randomized controlled trials assessing MIGS in English peer-reviewed journals were included, only observational studies with a target follow-up of at least one year and a high priority score were analyzed, resulting in a total of 3476 eyes across 20 trials. The mean age was 69.5 ± 2.9 years, 53.7% were female, and 77.4% were Caucasian. One study had last follow-up at less than one year, fifteen studies had follow-up extending 1-2 years, and four had longer than two years of follow-up. A pattern of more significant intraocular pressure and medication reduction was observed in patients who underwent MIGS (n = 2170) relative to control (n = 1306) interventions. iStent had the most literature supporting its efficacy, followed by Hydrus. The most common adverse events after MIGS implantation included stent obstruction, inflammation, and subsequent surgical intervention. Surgical complication rates and efficacy are favorable after MIGS. This review helps to consolidate the high-quality evidence that exists for various MIGS procedures and to identify gaps where further research is needed.