Ab-interno goniotrabeculotomy versus mitomycin C trabeculectomy for adult open-angle glaucoma: A 2-year randomized clinical trial

doi:10.1016/S0161-6420(99)00725-3

Ophthalmology

Volume 106, Issue 7, 1 July 1999, Pages 1357-1362

Presented in part at the American Academy of Ophthalmology annual meeting, New Orleans, Louisiana, November 1998.

https://doi.org/10.1016/S0161-6420(99)00725-3 Get rights and content

Abstract

Objective

To evaluate the effect of ab-interno goniotrabeculotomy (AIGT) on the intraocular pressure (IOP) in adult patients with primary open-angle glaucoma (POAG), compared with the effects of mitomycin C trabeculectomy (MT).

Design

Prospective, randomized, clinical trial.

Participants

Thirty-two eyes of 32 patients with medically uncontrolled POAG.

Intervention

Standard limbus-based trabeculectomy with adjunct mitomycin C (0.3 mg/mL for 3 minutes) in 16 eyes of 16 patients; AIGT was performed in 16 eyes of 16 patients. The groups were matched for age, preoperative IOP, duration of preoperative antiglaucoma treatment, use of preoperative beta-blockers and parasympathomimetics, and use of beta-blockers in the fellow eye. The IOP (average of the two highest values measured in the diurnal curve, from 8 am to 6 pm, every 2 hours) and complications were recorded 1, 3, 6, 12, 18, and 24 months after surgery.

Main outcome measures

Identification of complications and IOP.

Results

All patients were followed up for 24 months. More postoperative complications occurred in the MT group during the 2-year follow-up. One month after surgery, IOP was 10 ± 1.46 mmHg (range, 8–13) in the MT group and 12.12 ± 1.63 mmHg (range, 8–14) in the AIGT group (Student’s t test, P = 0.001). Three months after surgery, IOP was 11.5 ± 1.59 mmHg (range, 8–14) and 12.75 ± 1.57 mmHg (range, 10–16) in the MT and AIGT groups, respectively (Student’s t test, P = 0.033). From the 6th to the 24th postoperative month, no statistically significant difference in IOP was found between the two groups. At the end of follow-up, 14 of 16 eyes (87.5%) of the AIGT group and 13 of the 16 eyes (81.25%) of the MT group showed an IOP ≤14 mmHg.

Conclusion

Ab-interno goniotrabeculotomy appears to be a viable and safe surgical treatment for adult POAG. More extended follow-up, however, and a larger series of patients are needed to ascertain the actual effectiveness of this procedure in adult POAG.

Section snippets

Patients and methods

From January 1993 to March 1994, 32 eyes of 32 consecutive white patients with medically uncontrolled POAG were enrolled for this study.

Patients were selected for glaucoma surgery on the basis of confirmed significant progression of anatomic and functional damage, in the presence of an inadequately controlled IOP on medical therapy.

All the patients were recruited from the Glaucoma Service, Clinica Oculistica, Brescia. Eligibility criteria were as follows: (1) no previous bulbar surgery; (2) IOP

Results

All patients completed the 24-month follow-up. In the MT group, 9 of the 16 eyes underwent uncomplicated argon laser suture lysis within 3 weeks after surgery (only one of the two sutures was released).

During the AIGT procedure, bleeding from the iridocorneal angle was evident in 6 cases (37.5%) at the time of the incision. In all cases, the bleeding was extremely modest and stopped spontaneously.

No major postoperative complications were recorded in the AIGT group during the follow-up, other

Discussion

Our results provide evidence that AIGT is able to induce a significant decrease in IOP in adult POAG, with fewer postoperative complications than MT. Moreover, no significant differences in IOP and a similar success rate (IOP ≤14 mmHg without any hypotensive therapy: AIGT = 87.5%, MT = 81.25%; Fisher’s exact test, P = 1) were found between the two groups at the end of follow-up.

In our series, MT was associated with early-onset and late-onset complications, similar to those reported in other

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Cited by (22)

The changing conceptual basis of trabeculectomy: A review of past and current surgical techniques
2012, Survey of Ophthalmology
Citation Excerpt :
There is limited data on goniotomy in adult glaucoma. In a randomized clinical trial on 32 eyes of 32 patients, 16 underwent goniotomy and 16 had MMC SK.201 At 24 months, 14 of 16 eyes (87.5%) of the goniotomy group and 13 of the 16 eyes (81.25%) of the SK group showed an IOP ≤ 14 mm Hg.
The original intent of glaucoma surgery was to allow aqueous humor to exit more easily either through the sclera or into the suprachoroidal space. The former came to be called, generically, a glaucoma filtering procedure. As this surgery evolved, some explored the concept of lowering pressure without producing a hole in the sclera, with its resultant “filtering bleb.” For example, Cairns hoped that cutting open the edges of Schlemm’s canal would allow aqueous to leave without producing a filtering bleb; however, it became apparent that Cairns’s “trabeculectomy” only worked when a filtering bleb developed. The goal of today’s trabeculectomy is the creation of a longlasting transscleral fistula. In fact, trabeculectomy is a misnomer as excision of trabecular meshwork is unimportant. Frequently, the tissue excised to create a trans-scleral fistula is sclera, cornea, or both. The current trabeculectomy is really a guarded sclerokeratectomy. Newer techniques hope to increase aqueous outflow through Schlemm’s canal to avoid complications associated with subconjunctival filtering blebs. Non-penetrating glaucoma surgeries (deep sclerectomy, viscocanalostomy) and ab interno trabecular surgery attempt to lower intraocular pressure with bleb-less procedures. We describe the recent evolution of glaucoma surgery, particularly the idea that intraocular pressure may be lowered satisfactorily without creating a filtering bleb.
Efficacy and safety of a steel drainage device implanted under a scleral flap
2009, Canadian Journal of Ophthalmology
Objective: To evaluate the efficacy and safety of a stainless steel miniature glaucoma drainage device (Ex-PRESS X200) implanted under a scleral flap for the surgical treatment of primary open-angle glaucoma (POAG).
Study Design: Clinical, prospective, noncomparative, nonrandomized study. The efficacy and safety were evaluated on the full sample, with a minimum follow-up of 12 months (maximum 24, mean 18).
Participants: Thirty-seven eyes of 35 patients.
Methods: The Ex-PRESS device was implanted under a scleral flap in patients with POAG.
Results: Preoperative intraocular pressure (IOP) was 27.6 (SD 8.7) mm Hg; at last follow-up, IOP was 12.4 (SD 3.4) mm Hg (55.1% reduction). The success rates (IOP < 18 mm Hg and < 15 mm Hg at last visit without medications) were 78.4% (29/37) and 70.3% (26/37), respectively. Kaplan-Meier analyses (probability of IOP < 18 mm Hg and < 15 mm Hg without medications) at last follow-up were 72.6% and 47.9%, respectively. Early postoperative complications were clinically mild and included postoperative IOP < 5 mm Hg: 12 cases at 1 day, 8 cases at 1 week, 3 cases at 1 month, 1 case at 3 months; serous choroidal detachment: 9 cases, of which 3 spontaneously resolved, whereas in 6 cases, hypotony and flat chamber were treated with viscoelastic injection in the anterior chamber. At last follow-up, 6 patients were treated with 2 IOP-lowering medications. No sight-threatening consequences of surgery were observed. There were 8 cases (21.6%, n = 37) of bleb needling.
Conclusions: Our data support the efficacy and safety of the implantation of this device under a scleral flap. The IOP reduction obtained was significant and long standing and complications were mild.
Objet: Évaluation de l’efficacité et de la sécurité des appareils miniatures en acier inoxydable pour le drainage du glaucome (Ex-PRESS X200) insérés sous le volet scleral lors du traitement chirurgical du glaucome primaire à angle ouvert (GPAO).
Nature: Étude clinique, prospective, non comparative et non randomisée. L’efficacité et la sécurité ont été évaluées sur tout l’échantillonnage avec un suivi minimal de 12 mois (maximal 24, moyen 18). Participants: Trente-sept yeux de 35 patients.
Méthodes: L’appareil Ex-PRESS X200 a été inséré sous le volet scléral chez les patients atteints de GPAO.
Résultats: La pression intraoculaire (PIO) postopératoire était de 27,6 (ÉT 8,7) mm Hg; au dernier suivi, la PIO était de 12,4 mm Hg (ÉT 3,4); une baisse de 55,1 %. Les taux de réussite (PIO < 18 mm Hg et < 15 mm Hg à la dernière visite sans médicament) étaient de 78,4 % (29/37) et 70,3 % (26/37), respectivement. Les analyses de Kaplan-Meier (probabilité de PIO < 18 mm Hg et < 15 mm HG sans médicament) du dernier suivi étaient de 72,6 % et 47,9 % respectivement. Les complications postopératoires précoces étaient cliniquement légères et comprenaient une PIO post opératoire < 5 mm Hg; 12 cas au 1^er jour, 8 cas à 1 semaine, 3 cas à 1 mois, 1 cas à 3 mois; un décollement choroïdien séreux: 9 cas, parmi lesquels 3 se sont résolus spontanément, alors que dans 6 cas, l’hypotonie et la chambre plate ont été traitées avec des injections viscoélastiques dans la chambre antérieure. Au dernier suivi, 6 patients ont été soignés avec 2 médicaments pour abaisser la PIO. On n’a observé aucune conséquence menaçant la vue. Il y eut 8 cas (21,6 %, n = 37) de révision à l’aiguille de la bulle.
Conclusions: Nos données soutiennent l’efficacité et la sécurité de l’insertion de cet appareil sous le volet scléral. La réduction de la PIO obtenue était significative et durable et les complications étaient légères.
Canaloplasty: Circumferential viscodilation and tensioning of Schlemm canal using a flexible microcatheter for the treatment of open-angle glaucoma in adults. Two-year interim clinical study results
2009, Journal of Cataract and Refractive Surgery
Citation Excerpt :
In general, the Collaborative Initial Glaucoma Treatment Study2 found IOP in the range of 14 to 15 mm Hg over the 4 to 5 years of follow-up. Other comparative studies of trabeculectomy6,26–31 report a mean IOP after 2 years in the range of 10.1 to 16.9 mm Hg and mean medication use in the range of 0.1 to 1.2 medications. The lowest IOP and medication results were usually associated with the use of adjunctive antimetabolites and careful postoperative management of the eye.6,11,14
To evaluate 2-year postsurgical safety and efficacy of canaloplasty (circumferential viscodilation and tensioning of the inner wall of Schlemm canal) to treat open-angle glaucoma (OAG).
Multicenter surgical sites.
This international prospective study comprised adult OAG patients having glaucoma surgery or combined glaucoma–cataract surgery. Qualifying preoperative intraocular pressure (IOP) was at least 16 mm Hg and historical IOP, at least 21 mm Hg. The full circumference of the canal was viscodilated and a trabecular tensioning suture placed with a microcatheter. Primary outcome measures included IOP and glaucoma medication use.
At 24 months, all 127 eyes (127 patients) had a mean IOP of 16.0 mm Hg ± 4.2 (SD) and mean glaucoma medication use of 0.5 ± 0.8 (baseline values 23.6 ± 4.8 mm Hg and 1.9 ± 0.8 medications). Eyes with canaloplasty alone had a mean IOP of 16.3 ± 3.7 mm Hg and 0.6 ± 0.8 medications (baseline values 23.2 ± 4.0 mm Hg and 2.0 ± 0.8 medications). Eyes with combined glaucoma–cataract surgery had a mean IOP of 13.4 ± 4.0 mm Hg and 0.2 ± 0.4 medications (baseline values 23.1 ± 5.5 mm Hg and 1.7 ± 1.0 medications). The IOP and medication use results at all time points were statistically significant versus baseline (P <.001). The late postoperative follow-up identified 3 patients with elevated IOP. No other serious ocular or nonocular complications were reported.
Canaloplasty was safe and effective in reducing IOP in adult patients with OAG.
Magnetic Resonance Imaging in Patients Implanted with Ex-PRESS Stainless Steel Glaucoma Drainage Microdevice
2009, American Journal of Ophthalmology
To evaluate whether artifacts caused by a stainless steel glaucoma drainage device can alter the interpretation of magnetic resonance imaging (MRI) scans of the optic nerve and brain.
Consecutive case series.
Five patients (7 eyes) with Ex-PRESS devices (Optonol Ltd, Neve Ilan, Israel) positioned at the limbus were studied. For each subject, an axial T1-weighted, axial and coronal T2-weighted with fat saturation, and whole brain proton density (PD)/T2-weighted MRI scan was obtained. Standard MRI protocol was not optimized for the imaging of patients harboring Ex-PRESS implants. The effects of the device on PD/T2 pulse sequence imaging of the optic nerve and brain were rated from 1 (optic nerve margins unidentifiable or brain details altered) to 5 (excellent visualization of the optic nerve and brain).
For optic nerve visualization, 1 optic nerve scored 2, 3 optic nerves scored 3, and 3 optic nerves scored 4 (mean, 3.3 ± 0.8 standard deviation). For whole brain imaging, 4 patients scored 4 and 1 patient scored 5 (mean, 4.2 ± 0.4 standard deviation).
Our data demonstrate that interpretation of MRI scans of the orbit and brain is unaffected by the artifacts caused by the Ex-PRESS shunt, whereas optic nerve imaging may be affected. We are unaware of previous reports of this finding and could find no reference to it in a computerized search using PubMed.
Combined clear corneal phacoemulsification and ab interno trabeculectomy: Three-year case series
2005, Journal of Cataract and Refractive Surgery
Citation Excerpt :
Experimental studies24,25 show that incising the trabecular meshwork and Schlemm's canal can increase outflow. Clinical studies18,26–29 confirmed that trabecular incision or trabecular removal can effectively reduce IOP. Incisional ab interno techniques have been modified over the years by several authors26–28 and have received renewed interest from ophthalmologists both for the treatment of juvenile glaucoma30,31 as well as for chronic open-angle glaucoma.29,32,33
To evaluate the efficacy and safety of a novel surgical approach, ab interno trabeculectomy, in a combined procedure (clear corneal phacoemulsification + ab interno trabeculectomy) for the management of concurrent cataract and glaucoma with prognostic factors for filtration failure.
Department of Ophthalmology, Palmanova Hospital, Udine, Italy.
A prospective noncomparative case series of 11 eyes of 11 consecutive cataract patients with medically uncontrolled primary open-angle glaucoma or pseudoexfoliation glaucoma was performed. Each patient had phacoemulsification + intraocular lens implantation + ab interno trabeculectomy, which consisted of a gonioscopically controlled ab interno removal of a quadrant (3 clock hours) of the trabecular meshwork. The main outcome measures were intraocular pressure (IOP), the number of antiglaucomatous medications used, and complications.
Ten patients completed a 3-year follow-up. One patient had further surgery because of poor IOP control; in this case, the last valid observation was carried forward for IOP calculation. Mean preoperative IOP and IOPs measured 1, 3, 6, 12, 24, and 36 months after surgery were 25.0, 15.8, 15.4, 15.4, 15.2, 15.0, and 15.3 (−38.56%) mm Hg respectively. The number of medications averaged 2.4 before surgery and dropped to 0.8 at the end of follow-up. No major complications occurred during the follow-up period.
The new surgical procedure combining phacoemulsification with ab interno trabeculectomy can induce a clinically relevant decrease in IOP in eyes with cataract and glaucoma with poor prognosis for filtering surgery. However, a randomized controlled clinical trial with a more extended follow-up and a larger series of patients is needed to ascertain the actual effectiveness and safety of this procedure.
The quality of reporting of randomized clinical trials published in Ophthalmology
2001, Ophthalmology
To evaluate the quality of reporting of all the new randomized clinical trials published during 1999 in Ophthalmology using the CONSORT statement parameters.
Descriptive series of published studies.
Randomized clinical trials.
Eligible studies were all randomized clinical trials published in Volume 106 (1999) of Ophthalmology that reported the results of prospectively conducted studies in humans comparing two or more therapeutic options with regard to their effect on one or various outcomes, in which the authors stated that a process of randomization or quasi-randomization was performed before the interventions. Each study was evaluated by two independent observers establishing the specific report in the published manuscript of 57 CONSORT statement descriptors, and consensus was obtained between evaluators.
Overall presence of CONSORT statement descriptors in published reports.
The mean number of positive CONSORT descriptors for the 24 eligible randomized clinical trials was 33.42 (standard error of the mean [SEM] 1.57) of 57 possible. This score was significantly different (P < 0.001) from the score of 16.6 (standard error of the mean 0.6) reported for Ophthalmology in the 1991 to 1994 study by Scherer and Crawley. Of the nine descriptors measuring the quality of abstract reporting, a mean of 6.25 (SEM 0.3) was included in the 24 study abstracts evaluated, significantly different from the Scherer and Crawley score (5.2, SEM 0.2. P < 0.001). Four and six descriptors increased and decreased, respectively, their reporting in more than 20%. Key descriptors such as hypothesis postulation, primary outcome determination, sample size calculations, and a discussion of the limitations of the study such as bias, imprecision, and internal validity are still reported in less than 42% of clinical trials.
This study describes for the first time after the adoption of the CONSORT statement recommendations the status on the quality of reporting of recently published randomized clinical trials in Ophthalmology. Although not a direct measure of the intrinsic quality of a study, reporting quality provides the reader with useful tools for the evaluation of its validity. The quality of reporting of randomized clinical trials shows an overall improvement when compared with the period between 1991 and 1994. However, there is still significant room for improvement, especially in descriptors essential for the validation of clinical trial results that are still widely underreported.

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Ab-interno goniotrabeculotomy versus mitomycin C trabeculectomy for adult open-angle glaucoma: A 2-year randomized clinical trial

Abstract

Objective

Design

Participants

Intervention

Main outcome measures

Results

Conclusion

Section snippets

Patients and methods

Results

Discussion

Mitomycin as adjunct chemotherapy with trabeculectomy

Ophthalmology

Trabeculectomy with mitomycin A comparative study with fluorouracil

Arch Ophthalmol

The risk profile of mitomycin C in glaucoma surgery

Current Opinion in Ophthalmology

Intraoperative mitomycin versus postoperative 5-fluorouracil in high-risk glaucoma filtering surgery

Ophthalmology

Trabeculectomy with simultaneous topical application of mitomycin-C in refractory glaucoma

J Ocular Pharmacol

5-Fluorouracil and mitomycin C in pseudophakic patients

Ophthalmology

Mitomycin C versus 5-fluorouracil in high-risk glaucoma filtering surgery. Extended follow-up

Ophthalmology

A randomized study of trabeculectomy and subconjunctival administration of fluorouracil in primary glaucomas

Arch Ophthalmol

Low-dose and high-dose mitomycin trabeculectomy as initial surgery in primary open-angle glaucoma

Ophthalmology

Adjunctive mitomycin C in primary trabeculectomy in phakic eyes

Am J Ophthalmol

Mitomycin C primary trabeculectomy in primary glaucoma of white patients

J Glaucoma

Ocular hypotony after trabeculectomy with mitomycin C

Am J Ophthalmol

Hypotony after glaucoma filtration surgerymechanisms and incidence

J Glaucoma

Clinical and histopathologic observations concerning hypotony after trabeculectomy with adjunctive mitomycin C

Am J Ophthalmol

Hypotony maculopathy

Hypotony maculopathy following the use of topical mitomycin C in glaucoma filtration surgery

Ophthalmic Surg

Hypotony maculopathy after filtering surgery with mitomycin C. Incidence and treatment

Ophthalmology

Late onset of sequential multifocal bleb leaks after glaucoma filtration surgery with 5-fluorouracil and mitomycin C

Am J Ophthalmol

Late-onset bleb leaks after glaucoma filtering surgery

Arch Ophthalmol

Treatment of bleb infection after glaucoma surgery

Arch Ophthalmol

Blebitis, early endophthalmitis, and late endophthalmitis after glaucoma-filtering surgery

Ophthalmology

Late onset endophthalmitis associated with filtering blebs

Ophthalmic Surg

Sulla incisione dell’angolo irideo (Contribuzione alla cura del glaucoma)

Ann Ottalmol

Sulla cosidetta “sclerotomia” interna

Les indications de la goniotomie

Annee Ther Clin Ophtal

Indications for and results of irido-corneal angle incision. (Goniotomy, goniotrabeculotomy or trabeculectomy)

Trans Ophthal Soc New Zeal

Indications for and results of the operation of incision of the iridocorneal angle

Vestn Oftalmol