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Complications, Repair and Reoperation of Antiglaucoma Filtering Blebs
► VOL. 63, NO. 4
CONGENITAL CATARACT SURGERY
concepts. Highlights Ophth. 4:225, 1961. 7. Ryan, S. J., Blanton, F. M. and von Noorden, G. K: Surgery of congenital cataracts. Am. J. Ophth. 60 :S83, 1965.
8. Maumenee, A. E. and Goldberg, M. F. :
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Push-pull cataract aspiration and Franceschetti coreopraxy. Arch. Ophth. 74:72, 1965. 9. Cordes, F. C. : Failure in congenital cataract surgery : A study of 56 enucleated eyes. Am. J. Ophth. 43:1, 1957.
COMPLICATIONS, R E P A I R AND R E O P E R A T I O N O F ANTIGLAUCOMA F I L T E R I N G BLEBS H.
SAUL SUGAR,
M.D
Detroit, Michigan
The frequent complications resulting from filtering blebs have plagued ophthalmologists since the beginning of antiglaucoma filtration surgery shortly after the turn of the century. The management of these complications has always been difficult; probably it is some what less so today. The purpose of this paper is to describe experience with these various methods of management. The postoperative complications which we will consider are: (A) hypotony due to ex cessive filtration early in the postoperative course, (B) thin and grossly leaking blebs late in the postoperative course, (C) inade quately filtering blebs and (D) migration of the bleb onto the cornea. Late infection will not be considered in this paper. A. EXCESSIVE FILTRATION OF NORMAL BLEBS
Excessive filtration of filtering blebs of good thickness immediately after operation is quite common and usually decreases fol lowing the inflammatory reaction as the flap incision heals. It is due to the relatively ex cessive size of the fistulous tract. In cases of hypotony and shallow chambers, one may advise the patient to drink the equivalent of a liter of fluid during a period of five min utes once daily for a few days to increase the rate of aqueous formation and observe whether or not it improves the acuity of vi sion. If the hypotony and decreased vision perFrom the Sinai Hospital of Detroit and Wayne State University School of Medicine.
sist for several weeks, or if they occur late in the postoperative period, an attempt should be made to limit the area of filtration by use of a cautery or thermophore at the lateral borders of the bleb ; later, at its upper border, if necessary. If they persist, one should then test for the presence of an inadvertent small cyclodialysis by injecting dilute fluorescein into the anterior chamber and then making a small incision through the sclera over the ciliary body in the lower temporal quadrant. 17 If fluorescein-stained fluid is drained from the supraciliary space, such a cyclodialysis opening is presumed to be present and should be treated by apply ing cautery intrasclerally in two rows back of the limbus in the area of the original sur gical procedure and then by injecting air into the vitreous to help push the cleft closed. B. T H I N AND LEAKING BLEBS 1. T H I N BLEBS
Thin cystic blebs, in themselves, are dan gerous in that they are in constant danger of infection and/or rupture. Usually, instil lations of antibiotic drops are advisable. The bleb may be reinforced, if the thin area is large and the intraocular pressure is low, by bringing down a thin conjunctival flap over the thin bleb and suturing it in place after applying tincture of iodine to the bleb surface and abrading the corneal margin. Iliff1 described this method for closure of button-holed conjunctiva at the time of doing posterior lip sclerectomy. The fornix-based flap of conjunctiva is
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previous episodes of leaking bleb, it was decided to reinforce the bleb with a conjunctival flap, as already described. This was successful (fig. 1). 2. L E A K I N G BLEBS
Fig. 1 (Sugar). Reinforcing conjunctival fornixbased pedicle flap sutured to cornea and adherent to iodine-treated bleb surface. separated from Tenon's capsule by making an incision at the site of the previous con junctival incision and making it wide enough and long enough to cover the bleb and permit suturing it onto the peripheral two mm of the corneal margin. A little curve at its upper portion will add to its length. After the flap is free, it is pulled down into place and a single mattress suture is placed in the superficial sclera at the level of the original incision and tied over the middle third of half of the flap width so that the lower portion of the flap covers the bleb and corneal margin without any ten sion. T h e area of bleb to be covered by the flap and the abraded corneal margin are painted with 3 . 5 % tincture of iodine. T h e flap is then sutured to the cornea at each corner, in the center, and at each side. T h e sutures are removed after one to two weeks. If the tinc ture of iodine is inadequate, or if the flap is under any tension, it will pull off before that time. If this happens, it is not necessar ily serious since the hole has usually been epithelized during the time it was covered. Case of thin bleb treated with val flap reinforcement
conjuncti-
F. F., a 65-year-old woman, had had a corneoscleral trephination following which a leaking bleb was repaired with a Tenon's capsule pedicle graft. The bleb remained thin and the tension soft. Because of two previous infections and two
Collapse of the filtering bleb as the result of a tiny hole is usually an emergency which is associated, most of the time but not al ways, with collapse of the anterior chamber. Such leaking blebs are usually recognized by placing a drop of sterile fluorescein solution (not the Fluoristrips) on the surface of the bleb and watching for a tell-tale green rivu let of escaping aqueous. Because the fluid may not spontaneously escape from the leak in a hypotonie eye, the eye should be gently pressed upon while the leak area is observed biomicroscopically. T h e procedures used in management of a leaking bleb will be considered in progres sive order. First among these is the applica tion of a pressure bandage to the eye for one or two days. Cases treated with pressure
bandage
CASE 1
C. M., a 63-year-old woman, was first seen by me in 1956. In September of that year a corneoscleral trephination had been done on the left eye. In December, 1957, the patient struck her left eye against a cupboard door, rupturing the bleb. The anterior chamber was shallow. A Seidel test was positive.'A pressure bandage was applied for two days, after which the chamber was formed. Pres sure was continued. A week later the bleb was considered to be healed. CASE 2
W. S. (previously published in complete form15), a 49-year-old man, was first seen by me in Oc tober, 1958. In March, 1961, a limboscleral trephi nation was done on the left eye. In May, 1961, while I was on vacation, the patient complained of blurred vision and was seen by a colleague who found the anterior chamber to be flat and the bleb collapsed. A pressure bandage was ap plied. When seen by me two days later the eye was red, the chamber deep, the bleb intact but its sur face thin. After complete healing the bleb showed no cystic appearance. In June, 1966, another leak occurred in this eye. This was treated successful ly with conjunctival reinforcement (see later). Gehring 2 has described a method of applying pressure locally to the bleb through
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the closed lids with a sponge rubber block held by elastoplast. If inadequate, one may follow the classical conjunctival flap method, which has been used for at least 45 y e a r s to repair leaking blebs. 6 " 8 - 14 ' 16 It may solve the problem, although in my experience only one of seven such flaps drawn down directly from above the leaking bleb was successful. T h e conjunctiva and Tenon's capsule are incised immediately above the fistulous opening and a flap is dissected up. I t is made large enough to cover the upper corneal margin for about two mm. Sutures are placed in the cornea after denuding the corneal margin. T h e bleb is excised and the flap sutured in place. Because the flap used in this method of repair is part of the same flap previously dissected down in the original operation, there is some tendency to failure of filtra tion because of scarring. T o avoid this, flaps are dissected out of conjunctiva and Tenon's capsule lateral to the bleb (Callahan, 9 Sugar10). Cases in which a thick conjunctiva! flap was drawn down over the bared sclerectomy hole CASE 1
W. R., a 69-year-old woman, was seen by me in 1958. Her visual acuity was reduced to finger counting, R.E., and 20/80 corrected, L.E. Marked cupping was present in each eye. The intraocular pressure measured 25 mm Hg right and 42 mm Hg left. The tension in the left eye could not be con trolled medically and a corneoscleral trephination
Fig. 2 (Sugar). Lateral pedicle graft of conjunc tiva and Tenon's capsule.
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Fig. 3 (Sugar). Partially filtering bleb in same case as Figure 2. was done in May, 1958. Tenon's capsule was ex tremely thin and a spontaneous hole formed in the flap after a week. Two weeks later, after failure of a pressure bandage, a new flap was made from the lateral Tenon's tissue and conjunctiva as a pedicle and sutured to the cornea and sclera over the tre phine hole (fig. 2). The tension was controlled with Diamox but it has been as high as 29 mm Hg at times (fig. 3). CASE 2
N. S., a 64-year-old man, was first seen by me in January, 1955. Corrected vision in the left eye was 20/20 but the intraocular pressure remained between 27 and 31 mm Hg in spite of medical therapy. Corneoscleral trephination was done in March, 1955. The tension, vision and visual field were normal until October, 1957, when, as the re sult of mild late infection and a leak in the bleb, the anterior chamber collapsed. A conjunctivalTenon's capsule flap was drawn down and sutured to the corneal margin. The tension rose on the next day to 60 mm Hg and continued to be uncon trollable. A second corneoscleral trephination was done in November, 1957, with normal tension thereafter. A n important method of closing a leaking bleb was described by Fitzgerald and McCarthy. 3 A Tenon's capsule pedicle plug is inserted into the bleb behind the leak. T h e conjunctiva is ballooned out just above the upper limit of the bleb with local anesthetic solution. A n incision is made only through conjunctiva at the level of the superior rectus muscle insertion and the conjunctiva is undermined for about four mm (fig. 4 - A ) . A t the level of the upper limit of the bleb, Tenon's capsule is incised so the anterior wall of the bleb is dissected from the sclera
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Fig. 4 (Sugar). Diagrammatic description of operation (modified from description by Fitzgerald and McCarthy5). (A) Incision in con junctiva, exposing Tenon's capsule. (B) Formation of tongue of Tenon's capsule with free end above. (C) Tongue of Tenon's capsule turned down into bleb be hind conjunctival hole after making deep pocket behind conjunctival hole. In some cases, a fine doublearmed silk suture was inserted in the tip of the tongue graft and brought out through the corneal edge and tied. (D) Conjunctiva sutured with continuous catgut su ture.
down to the sclerolimbal junction. A tongue like flap of Tenon's capsule is prepared from above, just below the superior rectus tendon, and reflected down so as to form a pedicle flap (fig. 4-B and C). This is su tured to the corneal margin through the base of the flap with 6-0 silk. The bleb is reflected back and sutured in place (fig. 4-D). No attempt is made to suture the leak. Use of a Tenon's flap had been described by Stallard4 and MacLean.5 The latter, in performing a limboscleral type of trephination, separated the conjunctival and Tenon's capsule layers of the flap and a fold of Tenon's capsule was made by inserting two 6-0 double-armed black-silk sutures with atraumatic needles through the capsule from within outward, one on each side of the midline eight to nine mm apart and about six mm from the limbus. Cases of leaking blebs repaired Tenon's capsule plugs
had been treated for glaucoma for a year. The intraocular pressure was 36 mm Hg, R.E., 26 mm Hg, L.E. Vision was 20/20 each eye. The discs were excavated, more on the right. On maximal medication, the intraocular pressure in the right eye remained at 32 mm Hg; that in the left was always below 20 mm Hg. A corneoscleral trephination was done on the right eye in February, 1952 (fig. 5). The eye was in good condition until December, 1961, when the right eye became hypotonie and the vision was reduced to 20/50. The bleb area was very thin. In July, 1963, the right eye be came very soft and the retina appeared wrinkled.
with
CASE 1
J. R., a 33-year-old man with pigmentary glaucoma was seen by me in December, 1952. He Fig. 5 (Sugar). Filtering bleb in patient J.R., 1952.
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A positive Seidel test was found (fig. 6). A Fitzgerald type repair with a Tenon's capsule ped icle was done in July, 1963, with the insert su tured to the cornea (fig. 7). Healing was unevent ful, but the bleb became small and the pressure rose to 29 mm Hg three weeks postoperatively. On \% pilocarpine and Glaucon it has remained under 20 mm Hg since. The vision returned to 20/25, R.E. (-2.0D sph C +0.5D cyl ax 95°). The visual fields are normal to 1/330 and 2/1000 white targets. CASE 2
R. R., a 42-year-old man with chronic openangle glaucoma, was first seen by me in June, 1953, because of blurring of the left eye associ ated with headache. The intraocular pressure measured 25 mm Hg, R.E., and 36 mm Hg, L.E. The vision was 20/20 in each eye and the fields were normal. On medical therapy the right ten sion rose to 36 mm Hg. A corneoscleral trephination was done in December, 1953, with normaliza tion of. tension. In November, 1964, the right eye became very soft and injected and a leak was recognized. Pressure and antibiotics were used but the leak became larger. Two days later a Tenon's pedicle flap was inserted behind the hole. It was not sutured. The tension has been con trolled with 1% pilocarpine. CASE 3
W. S., a 49-year-old man, was first seen by me in October, 1958. A complete history of the right eye in this case has been published.15 Because of inability to control the elevated intraocular pres sure medically, a right limboscleral trephination was done in March, 1961. The vision and pressure remained normal until October, 1963, when the right eye became red and very soft. A definite leak was found in the epithelium but the bleb and anterior chamber did not collapse. A Tenon's cap sule pedicle was inserted under the hole a week later. No suture was used. The bleb healed well and has remained normal since.
Fig. 6 (Sugar)..Same eye as Figure 5 after in sertion of Tenon's capsule pedicle graft behind hole in bleb. A silk suture was used here to hold tip of graft in place (1963).
Fig. 7 (Sugar). Same eye as Figures 5 and 6 after healing. CASE 4
F. F., a 55-year-old woman, was first dis covered to have glaucoma in May, 1956, when the intraocular pressure was found to be 27 mm Hg each eye. The tension was not controlled medi cally in the left eye and rose to 35 mm Hg. In May, 1958, a left corneoscleral trephination was performed. In 1959, a leak with infection oc curred but cleared with medical treatment. In No vember, 1961, the eye became red and cleared on antibiotics. Lens opacities reduced the corrected vision to 20/60. In July, 1964, the bleb showed a definite leak. The anterior chamber was shallow. A Tenon's capsule pedicle was inserted into the bleb behind the hole. The bleb healed but re mained thin in its center. The tension continued to be soft. Corrected vision was reduced to 20/100 due to increasing lens opacification. CASE 5
F. L., a 70-year-old French woman, was first seen by me in April, 1965. A Lagrange sclerecto my had been done in December, 1964. Her left vision was reduced to finger counting. The left tension was found to be 4.0 mm Hg (applanation) due to a hole in the thin conjunctiva over the sclerectomy (fig. 8). The anterior chamber was shallow and a choroidal detachment was present. A Tenon's pedicle was brought down from above and folded forward into the area of the hole and sutured to the cornea. The anterior chamber formed and the tension rose to 15 mm Hg within two weeks. However, five days later the hypotony recurred as the Tenon's capsule in sert shrank. A week later, during a repeated at tempt to close the conjunctival hole, it was real ized that the conjunctiva of the bleb was too thin and that the hole had become larger. The con junctiva was, therefore, removed and a flap of sclera, one third to one half of the sclera in thickness, was folded down into the sclerectomy hole. It was trimmed to fit and then sutured. It
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bleb shrank considerably in size and both required pilocarpine to control the intraocu lar pressure. In one other (Case 5, immedi ately preceding), a second attempt at using a Tenon's capsule plug was contemplated but the conjunctiva of the bleb was so thin that it was decided to close the limboscleral opening with a scierai tongue pedicle flap and then to perform a new filtering opera tion at a new site immediately. One may prefer to use the conjunctival pedicle flap reinforcement, previously de scribed for thin blebs, to close a leaking bleb. This may be the most satisfactory and certainly is technically easy. Cases treated with thin conjunctival flap reinforcement CASE 1
A. L., an 80-year-old woman, had been treated for glaucoma since 1955. A successful comeo scleral trephination had been performed on the left eye in 1955. She had no difficulty until March, 1966, when she began to have tearing and irritation of the left eye. A leaking bleb and col lapsed anterior chamber were found five days later (fig. 10). A conjunctival pedicle flap was drawn down from above as already described. The anterior chamber became deep on the after noon of the operation day and the flap was in good condition (fig. 11) until a week postoperatively when it was found to have retracted; the chamber was formed and the tension was 8.0 mm Hg. It has remained normal since.
Fig. 9 (Sugar). Same eye as Figure 8 after closing sclerectomy opening with a scierai pedicle flap and performance of a limboscleral trephination temporally. was found to be watertight by injecting saline into the anterior chamber through a previously prepared small corneal incision. A limboscleral trephination was then performed temporal to the previous sclerectomy (fig. 9). It was successful.
One of the problems encountered in mak ing a Tenon's capsule pedicle graft is the shrinkage of the graft tissue. This tends to occur in all cases and if the hole in the con junctiva is large enough, the shrunken plug permits continued leakage. In two cases the pedicle tissue contracted so that the filtering
Fig. 10 (Sugar). Leaking bleb with collapsed anterior chamber 11 years after comeoscleral tre phination.
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CASE 2
W. S., a 49-year-old man when first seen by me in October, 1958, has been the subject of a report on the clinical effect of corticosteroids on conjunctival filtering blebs." His left eye developed a spontaneous leak in 1961 after a limboscleral tre" phination. After use of a pressure bandage, the bleb healed and remained so until June, 1966, when a leak with a positive Seidel test but with out chamber collapse was present. A conjunctival tongue flap was used to reinforce the bleb. Heal ing was uneventful. The second recurrence of a leaking bleb in this patient without a cystic type of bleb lends strength to the thesis" that high doses of corticosteroids over a long period of time are damaging to the integrity of filtering antiglaucoma blebs. C. FAILURE OF THE FILTERING BLEB
When a filtering bleb fails to form posti operatively or tends to close later, it is due to failure, or relative failure, of the aqueous humor to reach the looser Tenon's capsule tissue because of an inadequate scierai fistula, which was either too small or incor rectly placed, plugged by lens, iris, ciliary body or vitreous, or closed by inflammatory scarring condensation of Tenon's capsule tissue. The treatment of the closing bleb may be considered in order: First, preventive treatment in doing a good technical procedure: using good flap thickness, careful cautery to prevent hemor rhage into the flap and a fistula of adequate
831
size properly placed. Miotics should be stopped one to several days before operation to minimize postoperative iritis. In addition, any methods to maintain flow of aqueous into the subconjunctival space should be used. These include use of a preliminary corneal incision for filling the chamber and the bleb with saline immediately after the operation, and avoidance of drugs, such as Diamox, which inhibit secretion in the post operative period. Corticosteroids should be used topically to limit inflammation. During the first few weeks one may use gentle bimanual massage. I do not permit the patient to do this himself. During the second week one may, if necessary, evert the wound edges by pressing with one finger posteriorly, with another finger held ante rior to the fistula. Between two and six weeks postoperatively, Fitzgerald and Mc Carthy 3 advise subconjunctival needling hori zontally along the lower, then the upper, margin of the bleb. McCulloch11 described a similar method, using a cataract knife passed subconjunctivally through the bleb, in one side and out the other, with the cut enlarged upward subconjunctivally. One may prefer to use the suction cup technique (Galin and associates12·13). The suction cup is applied over the bleb for 15 minutes in the same manner as for determination of pressure decay. If this fails, exploration of the site may be successful. In my experi ence, reoperation at another site is usually the most successful method if the attempts at early postoperative treatment fail. D. MIGRATION OF BLEB ONTO THE CORNEA
Fig. 11 (Sugar). Same eye as Figure 10, show ing fornix-based conjunctival pedicle flap sutured to the cornea.
When a filtering bleb extends onto the cornea, it may easily be dissected up from the cornea and the excess excised at the corneal margin. The conjunctival bleb itself must not be entered. Fitzgerald and Mc Carthy 3 use a Bard-Parker knife (No. 15 blade) to make a partially penetrating keratotomy through Bowman's membrane and the superficial corneal stroma just anterior to the corneolimbal junction in an attempt to pro-
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right eye in 1951. His best visual acuity was 20/30, R.E., and 20/70 L.E. He was referred because of a decreasing right visual field. The in traocular pressure was found to be normal. Ex tensions of the filtering blebs were present on the upper corneas, especially on the right eye (fig. 15). These extensions were removed surgically as already described (fig. 16). The visual field, a week later, was increased temporally to a re markable degree; it was practically the same as in June, 1965, before the field loss had occurred. The corrected right visual acuity rose to 20/20. REOPERATION
Fig. 12 (Sugar). Bleb one year after successful iridencleisis.
When a fistulizing operation is to be re peated, the choice of site for the reoperation is most important. It should be located in an
Fig. 13 (Sugar). Same bleb as in Figure 12 two years later, showing extension of bleb onto cor nea. duce a barrier to re-invasion of the corneal surface. I have found such a barrier of little avail. Repeated resection may be necessary. The following two cases of migration of the bleb are of particular interest since re pair served to relieve monocular diplopia in one and what appeared to be a decreasing visual field in the other.
Fig. 14 (Sugar). Same bleb as in Figure 12 and 13 after removal of the extension by undermining and excision of the extending portion.
CASE 1
W. C, a 67-year-old man, was first seen by me in 1960. An iridencleisis was done on the right eye for subacute angle-closure glaucoma (fig. 12). The tension and vision have remained normal since. In March, 1963, the patient complained of monocular diplopia with the right eye. The only possible finding to explain this was an extension of the filtering bleb onto the cornea (fig. 13). It was removed in May, 1963, by the method already described (fig. 14), with immediate relief of the diplopia. Repetition was required in January 1964. Only slight extension has appeared since then. CASE 2
I. J., a 54-year-old man, had had an iridenclei sis performed on the left eye in 1948 and on the
Fig. 15 (Sugar). Extension of filtering bleb onto cornea 15 years after iridencleisis operation.
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gration of the bleb onto the cornea. Princi ples and methods for their repair or reop eration are described. 18140 San Juan REFERENCES
Fig. 16 (Sugar). Same eye as Figure IS after ex cision of the extending portion of the bleb. area where conjunctival scarring from the original operative procedure is minimal. T h i s m a y be determined during the injec tion of local anesthetic solution into the subconjunctiva. T h e least scarring is evident where the conjunctiva close the limbus bal loons out most. If the previous bleb was in the 12-o'clock position, one must try to get as close to it as possible, provided the bal looning is good in this area. I n other words, the best compromise between closeness to the 12-o'clock position and the minimal con junctival scarring as manifest by good bal looning with anesthetic solution should be chosen as the site for reoperation. H e m o r rhage should be minimized by the use of cautery and the usual precautions to pro duce a leak-proof flap of Tenon's capsule and conjunctiva adhered to. SUMMARY
Surgically reparable postoperative compli cations following filtering operations for glaucoma include early excessive filtration, leaking blebs, inadequate filtration and mi
1. Iliff, C. E. : Flap perforation in glaucoma surgery sealed by a tissue patch. Arch. Ophth. 71:21S, 1964. 2. Gehring, R. R. : A new method for re forming anterior chambers after glaucoma opera tion. Arch. Ophth. 68:473, 1962. 3. Fitzgerald, J. R. and McCarthy, J. L. : Sur gery of the filtering bleb. Arch. Ophth. 68:453, 1962. 4. Stallard, H. B.: Eye Surgery. Bristol J. Wright & Sons Ltd., 1958, p. 644. 5. MacLean, A. L. : Corneoscleral trephining. Am. J. Ophth. 41:399, 1956. 6. Wagner, F. Behandlung von Bindehautfisteln nach Elliot-Trepanation. Klin. Mbl. Augenh. 142 : 1006,1963. 7. Dunnington, J. H. and Regan, E. F. : Late fistulization of operative wounds. Arch. Ophth. 43 :407, 1950. 8. Gradle, H. S. : The closure of traumatic subconjunctival corneoscleral fistula. Arch. Ophth. 50:154, 1921. 9. Callahan, A. : Surgery of the Eye : Diseases. Springfield, 111., Thomas, 1956, p. 273. 10. Sugar, H. S. : The Glaucomas. New York, Hoeber, 1957, ed. 2. 11. McCulloch, C. : The incision of inadequate filtration blebs. Tr. Canad. Ophth. Soc. 10:45, 1958. 12. Galin, M. A., Baras, I. and Caverò, R. : Stimulation of a filtering bleb. Arch. Ophth. 74:777, 1965. 13. Galin, M. A., Baras, I and McLean, J. M. : The mechanism of external filtration. Am. J. Ophth. 61:63, 1966. 14. Chandler, P. A. : Hypotony after a filtering operation. Am. J. Ophth. 30:484, 1947. 15. Sugar, H. S. : Clinical effect of corticoste roide on conjunctival filtering blebs. Am. J. Ophth. 59:854, 1965. 16. Paufique, L. and Bonnet, M. : Réfection des cicatrices filtrantes antiglaucomateuses indica tions et technique. Ann. Ocul. 197:866, 1964. 17. Chandler, P. A. and Grant, W. M. : Lectures in Glaucoma. Philadelphia, Lea & Febiger, 1965, p. 398.
CONGENITAL CATARACT SURGERY
concepts. Highlights Ophth. 4:225, 1961. 7. Ryan, S. J., Blanton, F. M. and von Noorden, G. K: Surgery of congenital cataracts. Am. J. Ophth. 60 :S83, 1965.
8. Maumenee, A. E. and Goldberg, M. F. :
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Push-pull cataract aspiration and Franceschetti coreopraxy. Arch. Ophth. 74:72, 1965. 9. Cordes, F. C. : Failure in congenital cataract surgery : A study of 56 enucleated eyes. Am. J. Ophth. 43:1, 1957.
COMPLICATIONS, R E P A I R AND R E O P E R A T I O N O F ANTIGLAUCOMA F I L T E R I N G BLEBS H.
SAUL SUGAR,
M.D
Detroit, Michigan
The frequent complications resulting from filtering blebs have plagued ophthalmologists since the beginning of antiglaucoma filtration surgery shortly after the turn of the century. The management of these complications has always been difficult; probably it is some what less so today. The purpose of this paper is to describe experience with these various methods of management. The postoperative complications which we will consider are: (A) hypotony due to ex cessive filtration early in the postoperative course, (B) thin and grossly leaking blebs late in the postoperative course, (C) inade quately filtering blebs and (D) migration of the bleb onto the cornea. Late infection will not be considered in this paper. A. EXCESSIVE FILTRATION OF NORMAL BLEBS
Excessive filtration of filtering blebs of good thickness immediately after operation is quite common and usually decreases fol lowing the inflammatory reaction as the flap incision heals. It is due to the relatively ex cessive size of the fistulous tract. In cases of hypotony and shallow chambers, one may advise the patient to drink the equivalent of a liter of fluid during a period of five min utes once daily for a few days to increase the rate of aqueous formation and observe whether or not it improves the acuity of vi sion. If the hypotony and decreased vision perFrom the Sinai Hospital of Detroit and Wayne State University School of Medicine.
sist for several weeks, or if they occur late in the postoperative period, an attempt should be made to limit the area of filtration by use of a cautery or thermophore at the lateral borders of the bleb ; later, at its upper border, if necessary. If they persist, one should then test for the presence of an inadvertent small cyclodialysis by injecting dilute fluorescein into the anterior chamber and then making a small incision through the sclera over the ciliary body in the lower temporal quadrant. 17 If fluorescein-stained fluid is drained from the supraciliary space, such a cyclodialysis opening is presumed to be present and should be treated by apply ing cautery intrasclerally in two rows back of the limbus in the area of the original sur gical procedure and then by injecting air into the vitreous to help push the cleft closed. B. T H I N AND LEAKING BLEBS 1. T H I N BLEBS
Thin cystic blebs, in themselves, are dan gerous in that they are in constant danger of infection and/or rupture. Usually, instil lations of antibiotic drops are advisable. The bleb may be reinforced, if the thin area is large and the intraocular pressure is low, by bringing down a thin conjunctival flap over the thin bleb and suturing it in place after applying tincture of iodine to the bleb surface and abrading the corneal margin. Iliff1 described this method for closure of button-holed conjunctiva at the time of doing posterior lip sclerectomy. The fornix-based flap of conjunctiva is
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previous episodes of leaking bleb, it was decided to reinforce the bleb with a conjunctival flap, as already described. This was successful (fig. 1). 2. L E A K I N G BLEBS
Fig. 1 (Sugar). Reinforcing conjunctival fornixbased pedicle flap sutured to cornea and adherent to iodine-treated bleb surface. separated from Tenon's capsule by making an incision at the site of the previous con junctival incision and making it wide enough and long enough to cover the bleb and permit suturing it onto the peripheral two mm of the corneal margin. A little curve at its upper portion will add to its length. After the flap is free, it is pulled down into place and a single mattress suture is placed in the superficial sclera at the level of the original incision and tied over the middle third of half of the flap width so that the lower portion of the flap covers the bleb and corneal margin without any ten sion. T h e area of bleb to be covered by the flap and the abraded corneal margin are painted with 3 . 5 % tincture of iodine. T h e flap is then sutured to the cornea at each corner, in the center, and at each side. T h e sutures are removed after one to two weeks. If the tinc ture of iodine is inadequate, or if the flap is under any tension, it will pull off before that time. If this happens, it is not necessar ily serious since the hole has usually been epithelized during the time it was covered. Case of thin bleb treated with val flap reinforcement
conjuncti-
F. F., a 65-year-old woman, had had a corneoscleral trephination following which a leaking bleb was repaired with a Tenon's capsule pedicle graft. The bleb remained thin and the tension soft. Because of two previous infections and two
Collapse of the filtering bleb as the result of a tiny hole is usually an emergency which is associated, most of the time but not al ways, with collapse of the anterior chamber. Such leaking blebs are usually recognized by placing a drop of sterile fluorescein solution (not the Fluoristrips) on the surface of the bleb and watching for a tell-tale green rivu let of escaping aqueous. Because the fluid may not spontaneously escape from the leak in a hypotonie eye, the eye should be gently pressed upon while the leak area is observed biomicroscopically. T h e procedures used in management of a leaking bleb will be considered in progres sive order. First among these is the applica tion of a pressure bandage to the eye for one or two days. Cases treated with pressure
bandage
CASE 1
C. M., a 63-year-old woman, was first seen by me in 1956. In September of that year a corneoscleral trephination had been done on the left eye. In December, 1957, the patient struck her left eye against a cupboard door, rupturing the bleb. The anterior chamber was shallow. A Seidel test was positive.'A pressure bandage was applied for two days, after which the chamber was formed. Pres sure was continued. A week later the bleb was considered to be healed. CASE 2
W. S. (previously published in complete form15), a 49-year-old man, was first seen by me in Oc tober, 1958. In March, 1961, a limboscleral trephi nation was done on the left eye. In May, 1961, while I was on vacation, the patient complained of blurred vision and was seen by a colleague who found the anterior chamber to be flat and the bleb collapsed. A pressure bandage was ap plied. When seen by me two days later the eye was red, the chamber deep, the bleb intact but its sur face thin. After complete healing the bleb showed no cystic appearance. In June, 1966, another leak occurred in this eye. This was treated successful ly with conjunctival reinforcement (see later). Gehring 2 has described a method of applying pressure locally to the bleb through
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the closed lids with a sponge rubber block held by elastoplast. If inadequate, one may follow the classical conjunctival flap method, which has been used for at least 45 y e a r s to repair leaking blebs. 6 " 8 - 14 ' 16 It may solve the problem, although in my experience only one of seven such flaps drawn down directly from above the leaking bleb was successful. T h e conjunctiva and Tenon's capsule are incised immediately above the fistulous opening and a flap is dissected up. I t is made large enough to cover the upper corneal margin for about two mm. Sutures are placed in the cornea after denuding the corneal margin. T h e bleb is excised and the flap sutured in place. Because the flap used in this method of repair is part of the same flap previously dissected down in the original operation, there is some tendency to failure of filtra tion because of scarring. T o avoid this, flaps are dissected out of conjunctiva and Tenon's capsule lateral to the bleb (Callahan, 9 Sugar10). Cases in which a thick conjunctiva! flap was drawn down over the bared sclerectomy hole CASE 1
W. R., a 69-year-old woman, was seen by me in 1958. Her visual acuity was reduced to finger counting, R.E., and 20/80 corrected, L.E. Marked cupping was present in each eye. The intraocular pressure measured 25 mm Hg right and 42 mm Hg left. The tension in the left eye could not be con trolled medically and a corneoscleral trephination
Fig. 2 (Sugar). Lateral pedicle graft of conjunc tiva and Tenon's capsule.
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Fig. 3 (Sugar). Partially filtering bleb in same case as Figure 2. was done in May, 1958. Tenon's capsule was ex tremely thin and a spontaneous hole formed in the flap after a week. Two weeks later, after failure of a pressure bandage, a new flap was made from the lateral Tenon's tissue and conjunctiva as a pedicle and sutured to the cornea and sclera over the tre phine hole (fig. 2). The tension was controlled with Diamox but it has been as high as 29 mm Hg at times (fig. 3). CASE 2
N. S., a 64-year-old man, was first seen by me in January, 1955. Corrected vision in the left eye was 20/20 but the intraocular pressure remained between 27 and 31 mm Hg in spite of medical therapy. Corneoscleral trephination was done in March, 1955. The tension, vision and visual field were normal until October, 1957, when, as the re sult of mild late infection and a leak in the bleb, the anterior chamber collapsed. A conjunctivalTenon's capsule flap was drawn down and sutured to the corneal margin. The tension rose on the next day to 60 mm Hg and continued to be uncon trollable. A second corneoscleral trephination was done in November, 1957, with normal tension thereafter. A n important method of closing a leaking bleb was described by Fitzgerald and McCarthy. 3 A Tenon's capsule pedicle plug is inserted into the bleb behind the leak. T h e conjunctiva is ballooned out just above the upper limit of the bleb with local anesthetic solution. A n incision is made only through conjunctiva at the level of the superior rectus muscle insertion and the conjunctiva is undermined for about four mm (fig. 4 - A ) . A t the level of the upper limit of the bleb, Tenon's capsule is incised so the anterior wall of the bleb is dissected from the sclera
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Fig. 4 (Sugar). Diagrammatic description of operation (modified from description by Fitzgerald and McCarthy5). (A) Incision in con junctiva, exposing Tenon's capsule. (B) Formation of tongue of Tenon's capsule with free end above. (C) Tongue of Tenon's capsule turned down into bleb be hind conjunctival hole after making deep pocket behind conjunctival hole. In some cases, a fine doublearmed silk suture was inserted in the tip of the tongue graft and brought out through the corneal edge and tied. (D) Conjunctiva sutured with continuous catgut su ture.
down to the sclerolimbal junction. A tongue like flap of Tenon's capsule is prepared from above, just below the superior rectus tendon, and reflected down so as to form a pedicle flap (fig. 4-B and C). This is su tured to the corneal margin through the base of the flap with 6-0 silk. The bleb is reflected back and sutured in place (fig. 4-D). No attempt is made to suture the leak. Use of a Tenon's flap had been described by Stallard4 and MacLean.5 The latter, in performing a limboscleral type of trephination, separated the conjunctival and Tenon's capsule layers of the flap and a fold of Tenon's capsule was made by inserting two 6-0 double-armed black-silk sutures with atraumatic needles through the capsule from within outward, one on each side of the midline eight to nine mm apart and about six mm from the limbus. Cases of leaking blebs repaired Tenon's capsule plugs
had been treated for glaucoma for a year. The intraocular pressure was 36 mm Hg, R.E., 26 mm Hg, L.E. Vision was 20/20 each eye. The discs were excavated, more on the right. On maximal medication, the intraocular pressure in the right eye remained at 32 mm Hg; that in the left was always below 20 mm Hg. A corneoscleral trephination was done on the right eye in February, 1952 (fig. 5). The eye was in good condition until December, 1961, when the right eye became hypotonie and the vision was reduced to 20/50. The bleb area was very thin. In July, 1963, the right eye be came very soft and the retina appeared wrinkled.
with
CASE 1
J. R., a 33-year-old man with pigmentary glaucoma was seen by me in December, 1952. He Fig. 5 (Sugar). Filtering bleb in patient J.R., 1952.
r
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A positive Seidel test was found (fig. 6). A Fitzgerald type repair with a Tenon's capsule ped icle was done in July, 1963, with the insert su tured to the cornea (fig. 7). Healing was unevent ful, but the bleb became small and the pressure rose to 29 mm Hg three weeks postoperatively. On \% pilocarpine and Glaucon it has remained under 20 mm Hg since. The vision returned to 20/25, R.E. (-2.0D sph C +0.5D cyl ax 95°). The visual fields are normal to 1/330 and 2/1000 white targets. CASE 2
R. R., a 42-year-old man with chronic openangle glaucoma, was first seen by me in June, 1953, because of blurring of the left eye associ ated with headache. The intraocular pressure measured 25 mm Hg, R.E., and 36 mm Hg, L.E. The vision was 20/20 in each eye and the fields were normal. On medical therapy the right ten sion rose to 36 mm Hg. A corneoscleral trephination was done in December, 1953, with normaliza tion of. tension. In November, 1964, the right eye became very soft and injected and a leak was recognized. Pressure and antibiotics were used but the leak became larger. Two days later a Tenon's pedicle flap was inserted behind the hole. It was not sutured. The tension has been con trolled with 1% pilocarpine. CASE 3
W. S., a 49-year-old man, was first seen by me in October, 1958. A complete history of the right eye in this case has been published.15 Because of inability to control the elevated intraocular pres sure medically, a right limboscleral trephination was done in March, 1961. The vision and pressure remained normal until October, 1963, when the right eye became red and very soft. A definite leak was found in the epithelium but the bleb and anterior chamber did not collapse. A Tenon's cap sule pedicle was inserted under the hole a week later. No suture was used. The bleb healed well and has remained normal since.
Fig. 6 (Sugar)..Same eye as Figure 5 after in sertion of Tenon's capsule pedicle graft behind hole in bleb. A silk suture was used here to hold tip of graft in place (1963).
Fig. 7 (Sugar). Same eye as Figures 5 and 6 after healing. CASE 4
F. F., a 55-year-old woman, was first dis covered to have glaucoma in May, 1956, when the intraocular pressure was found to be 27 mm Hg each eye. The tension was not controlled medi cally in the left eye and rose to 35 mm Hg. In May, 1958, a left corneoscleral trephination was performed. In 1959, a leak with infection oc curred but cleared with medical treatment. In No vember, 1961, the eye became red and cleared on antibiotics. Lens opacities reduced the corrected vision to 20/60. In July, 1964, the bleb showed a definite leak. The anterior chamber was shallow. A Tenon's capsule pedicle was inserted into the bleb behind the hole. The bleb healed but re mained thin in its center. The tension continued to be soft. Corrected vision was reduced to 20/100 due to increasing lens opacification. CASE 5
F. L., a 70-year-old French woman, was first seen by me in April, 1965. A Lagrange sclerecto my had been done in December, 1964. Her left vision was reduced to finger counting. The left tension was found to be 4.0 mm Hg (applanation) due to a hole in the thin conjunctiva over the sclerectomy (fig. 8). The anterior chamber was shallow and a choroidal detachment was present. A Tenon's pedicle was brought down from above and folded forward into the area of the hole and sutured to the cornea. The anterior chamber formed and the tension rose to 15 mm Hg within two weeks. However, five days later the hypotony recurred as the Tenon's capsule in sert shrank. A week later, during a repeated at tempt to close the conjunctival hole, it was real ized that the conjunctiva of the bleb was too thin and that the hole had become larger. The con junctiva was, therefore, removed and a flap of sclera, one third to one half of the sclera in thickness, was folded down into the sclerectomy hole. It was trimmed to fit and then sutured. It
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bleb shrank considerably in size and both required pilocarpine to control the intraocu lar pressure. In one other (Case 5, immedi ately preceding), a second attempt at using a Tenon's capsule plug was contemplated but the conjunctiva of the bleb was so thin that it was decided to close the limboscleral opening with a scierai tongue pedicle flap and then to perform a new filtering opera tion at a new site immediately. One may prefer to use the conjunctival pedicle flap reinforcement, previously de scribed for thin blebs, to close a leaking bleb. This may be the most satisfactory and certainly is technically easy. Cases treated with thin conjunctival flap reinforcement CASE 1
A. L., an 80-year-old woman, had been treated for glaucoma since 1955. A successful comeo scleral trephination had been performed on the left eye in 1955. She had no difficulty until March, 1966, when she began to have tearing and irritation of the left eye. A leaking bleb and col lapsed anterior chamber were found five days later (fig. 10). A conjunctival pedicle flap was drawn down from above as already described. The anterior chamber became deep on the after noon of the operation day and the flap was in good condition (fig. 11) until a week postoperatively when it was found to have retracted; the chamber was formed and the tension was 8.0 mm Hg. It has remained normal since.
Fig. 9 (Sugar). Same eye as Figure 8 after closing sclerectomy opening with a scierai pedicle flap and performance of a limboscleral trephination temporally. was found to be watertight by injecting saline into the anterior chamber through a previously prepared small corneal incision. A limboscleral trephination was then performed temporal to the previous sclerectomy (fig. 9). It was successful.
One of the problems encountered in mak ing a Tenon's capsule pedicle graft is the shrinkage of the graft tissue. This tends to occur in all cases and if the hole in the con junctiva is large enough, the shrunken plug permits continued leakage. In two cases the pedicle tissue contracted so that the filtering
Fig. 10 (Sugar). Leaking bleb with collapsed anterior chamber 11 years after comeoscleral tre phination.
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CASE 2
W. S., a 49-year-old man when first seen by me in October, 1958, has been the subject of a report on the clinical effect of corticosteroids on conjunctival filtering blebs." His left eye developed a spontaneous leak in 1961 after a limboscleral tre" phination. After use of a pressure bandage, the bleb healed and remained so until June, 1966, when a leak with a positive Seidel test but with out chamber collapse was present. A conjunctival tongue flap was used to reinforce the bleb. Heal ing was uneventful. The second recurrence of a leaking bleb in this patient without a cystic type of bleb lends strength to the thesis" that high doses of corticosteroids over a long period of time are damaging to the integrity of filtering antiglaucoma blebs. C. FAILURE OF THE FILTERING BLEB
When a filtering bleb fails to form posti operatively or tends to close later, it is due to failure, or relative failure, of the aqueous humor to reach the looser Tenon's capsule tissue because of an inadequate scierai fistula, which was either too small or incor rectly placed, plugged by lens, iris, ciliary body or vitreous, or closed by inflammatory scarring condensation of Tenon's capsule tissue. The treatment of the closing bleb may be considered in order: First, preventive treatment in doing a good technical procedure: using good flap thickness, careful cautery to prevent hemor rhage into the flap and a fistula of adequate
831
size properly placed. Miotics should be stopped one to several days before operation to minimize postoperative iritis. In addition, any methods to maintain flow of aqueous into the subconjunctival space should be used. These include use of a preliminary corneal incision for filling the chamber and the bleb with saline immediately after the operation, and avoidance of drugs, such as Diamox, which inhibit secretion in the post operative period. Corticosteroids should be used topically to limit inflammation. During the first few weeks one may use gentle bimanual massage. I do not permit the patient to do this himself. During the second week one may, if necessary, evert the wound edges by pressing with one finger posteriorly, with another finger held ante rior to the fistula. Between two and six weeks postoperatively, Fitzgerald and Mc Carthy 3 advise subconjunctival needling hori zontally along the lower, then the upper, margin of the bleb. McCulloch11 described a similar method, using a cataract knife passed subconjunctivally through the bleb, in one side and out the other, with the cut enlarged upward subconjunctivally. One may prefer to use the suction cup technique (Galin and associates12·13). The suction cup is applied over the bleb for 15 minutes in the same manner as for determination of pressure decay. If this fails, exploration of the site may be successful. In my experi ence, reoperation at another site is usually the most successful method if the attempts at early postoperative treatment fail. D. MIGRATION OF BLEB ONTO THE CORNEA
Fig. 11 (Sugar). Same eye as Figure 10, show ing fornix-based conjunctival pedicle flap sutured to the cornea.
When a filtering bleb extends onto the cornea, it may easily be dissected up from the cornea and the excess excised at the corneal margin. The conjunctival bleb itself must not be entered. Fitzgerald and Mc Carthy 3 use a Bard-Parker knife (No. 15 blade) to make a partially penetrating keratotomy through Bowman's membrane and the superficial corneal stroma just anterior to the corneolimbal junction in an attempt to pro-
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right eye in 1951. His best visual acuity was 20/30, R.E., and 20/70 L.E. He was referred because of a decreasing right visual field. The in traocular pressure was found to be normal. Ex tensions of the filtering blebs were present on the upper corneas, especially on the right eye (fig. 15). These extensions were removed surgically as already described (fig. 16). The visual field, a week later, was increased temporally to a re markable degree; it was practically the same as in June, 1965, before the field loss had occurred. The corrected right visual acuity rose to 20/20. REOPERATION
Fig. 12 (Sugar). Bleb one year after successful iridencleisis.
When a fistulizing operation is to be re peated, the choice of site for the reoperation is most important. It should be located in an
Fig. 13 (Sugar). Same bleb as in Figure 12 two years later, showing extension of bleb onto cor nea. duce a barrier to re-invasion of the corneal surface. I have found such a barrier of little avail. Repeated resection may be necessary. The following two cases of migration of the bleb are of particular interest since re pair served to relieve monocular diplopia in one and what appeared to be a decreasing visual field in the other.
Fig. 14 (Sugar). Same bleb as in Figure 12 and 13 after removal of the extension by undermining and excision of the extending portion.
CASE 1
W. C, a 67-year-old man, was first seen by me in 1960. An iridencleisis was done on the right eye for subacute angle-closure glaucoma (fig. 12). The tension and vision have remained normal since. In March, 1963, the patient complained of monocular diplopia with the right eye. The only possible finding to explain this was an extension of the filtering bleb onto the cornea (fig. 13). It was removed in May, 1963, by the method already described (fig. 14), with immediate relief of the diplopia. Repetition was required in January 1964. Only slight extension has appeared since then. CASE 2
I. J., a 54-year-old man, had had an iridenclei sis performed on the left eye in 1948 and on the
Fig. 15 (Sugar). Extension of filtering bleb onto cornea 15 years after iridencleisis operation.
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gration of the bleb onto the cornea. Princi ples and methods for their repair or reop eration are described. 18140 San Juan REFERENCES
Fig. 16 (Sugar). Same eye as Figure IS after ex cision of the extending portion of the bleb. area where conjunctival scarring from the original operative procedure is minimal. T h i s m a y be determined during the injec tion of local anesthetic solution into the subconjunctiva. T h e least scarring is evident where the conjunctiva close the limbus bal loons out most. If the previous bleb was in the 12-o'clock position, one must try to get as close to it as possible, provided the bal looning is good in this area. I n other words, the best compromise between closeness to the 12-o'clock position and the minimal con junctival scarring as manifest by good bal looning with anesthetic solution should be chosen as the site for reoperation. H e m o r rhage should be minimized by the use of cautery and the usual precautions to pro duce a leak-proof flap of Tenon's capsule and conjunctiva adhered to. SUMMARY
Surgically reparable postoperative compli cations following filtering operations for glaucoma include early excessive filtration, leaking blebs, inadequate filtration and mi
1. Iliff, C. E. : Flap perforation in glaucoma surgery sealed by a tissue patch. Arch. Ophth. 71:21S, 1964. 2. Gehring, R. R. : A new method for re forming anterior chambers after glaucoma opera tion. Arch. Ophth. 68:473, 1962. 3. Fitzgerald, J. R. and McCarthy, J. L. : Sur gery of the filtering bleb. Arch. Ophth. 68:453, 1962. 4. Stallard, H. B.: Eye Surgery. Bristol J. Wright & Sons Ltd., 1958, p. 644. 5. MacLean, A. L. : Corneoscleral trephining. Am. J. Ophth. 41:399, 1956. 6. Wagner, F. Behandlung von Bindehautfisteln nach Elliot-Trepanation. Klin. Mbl. Augenh. 142 : 1006,1963. 7. Dunnington, J. H. and Regan, E. F. : Late fistulization of operative wounds. Arch. Ophth. 43 :407, 1950. 8. Gradle, H. S. : The closure of traumatic subconjunctival corneoscleral fistula. Arch. Ophth. 50:154, 1921. 9. Callahan, A. : Surgery of the Eye : Diseases. Springfield, 111., Thomas, 1956, p. 273. 10. Sugar, H. S. : The Glaucomas. New York, Hoeber, 1957, ed. 2. 11. McCulloch, C. : The incision of inadequate filtration blebs. Tr. Canad. Ophth. Soc. 10:45, 1958. 12. Galin, M. A., Baras, I. and Caverò, R. : Stimulation of a filtering bleb. Arch. Ophth. 74:777, 1965. 13. Galin, M. A., Baras, I and McLean, J. M. : The mechanism of external filtration. Am. J. Ophth. 61:63, 1966. 14. Chandler, P. A. : Hypotony after a filtering operation. Am. J. Ophth. 30:484, 1947. 15. Sugar, H. S. : Clinical effect of corticoste roide on conjunctival filtering blebs. Am. J. Ophth. 59:854, 1965. 16. Paufique, L. and Bonnet, M. : Réfection des cicatrices filtrantes antiglaucomateuses indica tions et technique. Ann. Ocul. 197:866, 1964. 17. Chandler, P. A. and Grant, W. M. : Lectures in Glaucoma. Philadelphia, Lea & Febiger, 1965, p. 398.