Ординатура / Офтальмология / Английские материалы / Step by Step Minimally Invasive Glaucoma Surgery_Garg, Melamed, Bovet, Pajic, Carassa, Dada_2006

Open Angle Filter Surgery for Glaucoma 323

Usually, all eye hypotensor treatments are stopped, even if it is necessary for them to be re-introduced at a later date.

The filtration bubble that is found when trabectomy is used, does not exist using this technique. As a result, the patient has to be checked controlling the ocular tension in both the eyes. If possible, the measure has to be taken each time at the same hour, in order to avoid obtaining distorted results because of the curve of the nychthemeral ocular pressure.

Patients who are cortisone respondant need particularly special attention.

Continuous check-ups to control postoperative pressure are necessary in cases of glaucoma.

It is extremely important to check the preand postoperative pressures in the two eyes at the same times.

PEROPERATIVE COMPLICATIONS

The most frequent complication is rupture of the Descemet’s membrane when dissecting the second scleral flap: the rupture happens after the scleral spur and, especially, after the removal ? with diamond or Vannas scissors.

If this happens, it will be necessary to convert the deep sclerectomy into trabeculectomy without viscocanalostomy, whilst not forgetting to make an iridectomy.

When the canalostomy is done, the viscous fluid can leak into the anterior chamber. In the hours following the operation, this will cause a rapid increase in the intraocular pressure. The operation will have to be reviewed, by carrying out a paracentesis, emptying the viscous fluid and rinsing the anterior chamber.

The other possible complication is the perforation of the choroid, which has no postoperative importance.

324 Step by Step Minimally Invasive Glaucoma Surgery

The most frequent complication from using this technique is increased postoperative pressure, more or less long-term, due to the collapse or closing up/healing of the scleral flap on the bed of the operation. This is the reason why many authors have proposed different types of implants which very in the rapidity of their re-absorbtion.

Our technique uses an autograft from the sclera, soaked in mitomycin C2 which inhibits all fibrocyte proliferation. This produces the best results in the long term and the lowest costs. When, after this operation, pressure increases occur rarely, they can still happen after 3-4 years.

If there is a recurrence, nowadays we favor repeating the procedure in a more favorable quadrant. We have never had to repeat this operation more than twice.

We have stopped doing trabeculoplasty au yag for patients who have increased pressure after three weeks, this technique not having brought the expected results.

We do no longer convert our deep sclerocanalostomy into a trabeculectomy, because the complications were too important.

REFERENCES

1.Arenas E. Trabeculectomy ab externo. Highlights of Ophthalmol. World Atlas Series Vol. 1. 1993;216-18.

2.Arenas E. The routine use of mytomycine in trabeculectomy ab externo using a modified drill technique Highlights of Ophthalmol. World Atlas Series Vol. 2 1993;236-37.

3.Baumgartner JM, Bovet J, Baumgartner A. Etude de la stabilisation de la plaie opératoire et de la rapidité de la récupération fonctionnelle dans la chirurgie de la cataracte: Comparaison des résultat entre quatre techniques chirurgicales différentes Ophtalmologie 1995;9:624-25.

4.Bovet J. Deep lamellar sclerectomy, what’s new Eye Advance Mumbay India (abstract) Chairmann Keiki Metha August 2004.

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5.J Bovet, JM. Baumgartner, JC Bruckner, V Ilic, O Achard L’anesthésie topique en chirurgie oculaire et sa préparation In: Les Dimensions de la douleur en ophtalmologie A.B. Safran, T. Landis, P. Dayer eds Paris Masson, 1998;166173.

6.J Bovet, I Molnar, JM Baumgartner, F Failla, C Tabatabay Combined Glaucoma and cataract surgery (phacotrabeculectomy) European Ophtalmic Society (abstract), SOE 1997, Budapest.

7.Burian HM, Allen L. Trabeculotomy ab externo. A new glaucoma operation : technique and results of experimental surgery. Amer J Ophthalmol 1962;53:19-26.

8.Cairns JE. Trabeculectomy; preliminary report of a new method. Amer J Ophthalmol 1968;66:673.

9.Chiou AGY, de Courten C, Bovet J. Pseudophakic ametropia managed with a phakic posterior chamber intraocular lens. J Cataract Refract Surg 2001;27:1516-8.

10.Chiou AGY, Mermoud A, Underahl PJ, Schnyder CC. An ultrasound biomicroscopic study of eyes after deep sclerectomy with collagen implant. Ophtalmology 1998;105,4:104-8.

11.Demailly P, Jeanteur-Lunel MN, Berkani M, et al. Non penetrating deep slerectomy associated with collagen device in primary open angle glaucoma. Middle term retrospective study. J Fr Ophthalmol 1996; 19,11:659-66.

12.Fyodorov SN, Ioffe DI, Ronkina TI. Deep sclerectomy: technique and mechanism of a new glaucomatous procedure. Glaucoma 1984;6:281-383.

13.Goldmann H Drainage of aqueous in man. Ophthalmologica 1946;112:11-146.

14.Koslov VI & all. Non penetrating. Deep sclerectomy with collagen. I IRTC Eye Microsurgery. RSFSR Ministry of Public Health, Moscow 1990;3:44-46.

15.Krasnov MM. Externalization of Schlemm’s canal (sinusotomy) in glaucoma. Brit J Ophthalmol 52:157-161.

16.Kershner RM. Nonpenetrating trabeculectomy with placement of collagen drainage device. J Cataract Refract Surg 1995;21:6:608-611.

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17.Krasnov MM. Externalisation of Schlemm’s canal (sinusotomy) in glaucoma. Br J Ophthalmol 1968;52:15761.

18.Lebuisson DA, Bovet JJ. Le concept opératoire pour patients ophtalmologiques ambulants in Laroche L, Lebuisson DA, Montard M Chirurgie de la cataracte chap 6 pp 61-74ed Masson 1996.

19.Massy J, Gruber D, Muraine M, Brasseur G. Nonpenetrating Deep Sclerectomy: collagen implant and viscocanalostomy procedures. Bylsma S. Int Ophtalmol Clin 1999 Summer; 39(3):103-19.

20.Kozlov VI, Bagrow SN, Anisimova SY, et al. Deep sclerectomy with collagen. Eye microsurgery 1990;3:44-46.

21.Stegmann RC. Viscocanalostomy : a new surgical technique for open angle glaucoma. An Inst Barraque, Spain 1995;25:229-32.

22.Stegmann R, Piennaar A, Milller D. Viscocanalostomy for open-angle glaucoma in black African patients. J Cataract Refract Surg 1999;25:3,316-22.

23.Sampaolesi R. Glaucoma, 2nd edition, Editorial Médica Panamericana, Buenos Aires, 1991;525-26.

24.Perkins ES. Pressure in the canal of Schlemm. Brit J Ophthalmol 1955;39:215-19.

25.Sourdille P, Santiago PY, Villian F, et al. Reticulated hyaluronic acid implant in nonperforating trabecular surgery. J Cataract Refract Sur 1999;25:332-39.

26.Sugar HS. Experimental trabeculotomy in glaucoma. Am J Ophthalmol 1961;54:623-27.

27.Tanibara H, Negi A, Akimoto M, et al. Surgical effects of trabeculectomy ab externo on adults eyes with primary open angle glaucoma and pseudoexfoliation syndrome. Arch Ophthalmol 1993;111:1653-61.

28.Verges C, Llevat E. Non penetrating deep sclerectomy (NPDS) with an Er:YAG laser. Clinical results after 16 months follow-up ASCRS abstracts 2000;201.

29.Zimmerman ThJ, et al. Trabeculectomy vs. non penetrating trabeculectomy. A retrospective study of two procedures in phakic patients with glaucoma. Ophthalmic Surgery 1984;15:734-40.

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INTRODUCTION/INDICATIONS

Cataracts and glaucoma have always been linked together. The crystalline lens is responsible for most of secondary glaucoma, these come from a pseudoexfoliation or a simple hypertrophy of the crystalline lens. The diagnostic problem we find in combined surgery is to know what is the part played by each of these pathologies in ocular hypertension.18

When should we feel the need to propose a combined operation when a simple cataract operation is enough.12

A study by Jean-Marc Baumgartner has shown a lowering of 3 mm Hg of ocular tension in normal patients after a simple cataract operation using phacoemulsification.3

In Europe, more and more patients suffer, because of their age, from pseudoexfoliation. The problem is important in cataract operations, because, in a certain number of cases, pseudoexfoliation leads to a zonulolysis that can develop into total lysis. The lens then falls into the vitreous fluid. On the other hand, pseudoexfoliation increases the pressure by deposit of hyaloids on the trabeculum level.21

The crystalline lens, whilst increasing in size, can diminish the flow of aqueous humor, especially in the hypermetropic eye with narrow anterior chamber.

For all glaucoma and cataract surgery, the goal is to solve the two problems in one operation, without increasing postoperative risks and extending recovery time.6,20

Nowadays, the new operating techniques for cataract allow intervention by paracentheses of less than 1.2 mm and an implantation of the lens using an incision of 1.7 mm.5

Bimanual Microphaco and Deep Sclerocanalostomy 329

This removes all problems of astigmatism induced by the operation.

This new technique allows less postoperatives checks and a faster visual recovery.3

Non-perforating surgery techniques for glaucoma, not only have a small number of postoperative complications, but also have the advantage of producing a very rapid recovery.9

We are going to describe our combined operation for cataracts/glaucoma using 2 new techniques.4,8

•one, Bimanual Microphaco technique for cataracts

•the other, deep sclerocanalostomy

In the combined operation, timing of the two operations

is important.

Several authors prefer to perform each of these operations separately at different sites. After having tried multiple combinations, either on one or two sites, it seemed to us that the best solution was to start on one side by dissecting the first flap up to the scleral blade, then to do a bimanual microphaco on a temporal site, at the end, finishing the second flap and the canalostomy under viscoelastic solution in the anterior chamber.11

This has several advantages: dissection of the first flap is done on an eye with healthy pressure, dissection is made easier, the cataract surgery is carried out without any risk of rupturing the Descemet and, in the end, the dissection of the second flap is carried out with weak intercamerular pressure, so diminishing risk of rupturing the Descemet.

Non-penetrative surgical techniques do not have the postoperative complications of the first, penetrative, surgery, but they are more difficult to carry out. An exact knowledge of the micro-anatomy of the region is important and a learning curve necessary.

330 Step by Step Minimally Invasive Glaucoma Surgery

We submit to you two new surgical techniques with specific timings, allowing glaucoma and cataract operations to be done with the minimum of risk.

The operation reduces the risks inherent in each technique, whilst increasing the long-term chances of success.

SURGICAL TECHNIQUE

1st Stage: Glaucoma

1st Scleral Flap

Sclera flap under local anesthetic and subconjunctival bubble in outpatient surgery (Figs 20.1A and B).15

This anesthetic technique has been described in the previous chapter.

Let us remember that this local anesthetic allows - thanks to the patient’s ability to participate - exposure of the operative field for dissection and its best, and variable angles of work.7,10

Choices for dissection: The path of dissection and flap’s localization are chosen to spare the penetrating vessels and to search for the zone that is the most avascular.

The draining vessels are on the surface, as shown by Stegmann.

The choice of the best place for the flap to spare the penetrating vessels to find the most avascular zone, one must not forget that the draining vessels are on the surface, as shown by Stegmann in his film.19

Conjunctival shutter with limb

Stages are as follows:

•Dissection of the conjunctival shutter with limb, not less than 10 mm, with Vescoat scissors. Dissection in an L