Visual acuity after penetrating keratoplasty for pseudophakic and aphakic bullous keratopathy

Visual acuity after penetrating keratoplasty for pseudophakic and aphakic bullous keratopathy Patrick Schraepen, MD, Carina Koppen, MD, Marie-Jose´ Tassignon, MD, PhD Purpose: To identify prognostic factors that determine the visual acuity after penetrating keratoplasty (PKP) for bullous keratopathy secondary to cataract surgery. Setting: Department of Ophthalmology, University Hospital Antwerp, Antwerp, Belgium. Methods: Twenty-six patients who had PKP for bullous keratopathy were examined before and after surgery. The patients were divided into 3 groups: pseudophakic bullous keratopathy (PBK) after cataract extraction with implantation of a posterior chamber intraocular lens (PC IOL) (Group 1) or an anterior chamber IOL (AC IOL) (Group 2); aphakic bullous keratopathy (ABK) (Group 3). The following parameters were recorded: preoperative and postoperative visual acuity, age at the time of surgery, interval between cataract surgery and development of bullous keratopathy, presence of an AC IOL or a PC IOL, aphakia, and presence of concomitant ocular pathology. Results: Visual acuity improved in Group 1 (0.02 to 0.26); no visual improvement was observed in the other groups. Posterior segment damage occurred in one third of the patients in Group 1 and in all patients in the other groups. Patients with an intact posterior segment had a significantly better visual outcome. In eyes without posterior segment pathology, visual acuity improved from a mean of 0.03 (range 0 to 0.20) to a mean of 0.37 (range 0.03 to 0.90). In eyes with posterior segment pathology, no visual acuity improvement could be obtained. Conclusion: The most important negative prognostic factors affecting visual acuity were the presence of concomitant ocular pathology, an AC IOL, and a long interval between surgery and the development of bullous keratopathy. J Cataract Refract Surg 2003; 29:482– 486 © 2003 ASCRS and ESCRS

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ullous keratopathy is a major complication of cataract surgery. In most cases, penetrating keratoplasty (PKP) is the only effective therapy for the symptomatic stage of the condition.1,2 Survival of a donor cornea in bullous keratopathy has been extensively studied.3–5 Although the short-term graft survival rate is good (74% at 5 years3), visual improvement is often poor.4,6 In this study, we looked at prognostic factors that determine the visual outcome after PKP for bullous keratopathy after cataract surgery. Accepted for publication June 25, 2002. Reprint requests to Patrick Schraepen, MD, University Hospital Antwerp, Department of Ophthalmology, Wilrijkstraat 10, 2650 Edegem, Belgium. © 2003 ASCRS and ESCRS Published by Elsevier Science Inc.

Patients and Methods The study comprised 26 eyes of 26 patients who were referred for treatment of symptomatic bullous keratopathy and had PKP from 1997 to 1999. Only patients who experienced pain that could not be relieved by medical treatment or surgical techniques, including phototherapeutic keratectomy (PTK), were included. Twenty-four patients presented with pseudophakic bullous keratopathy (PBK); 16 eyes had a posterior chamber intraocular lens (PC IOL) (Group 1) and 8 eyes had an anterior chamber IOL (AC IOL) (Group 2). Two eyes presented with aphakic bullous keratopathy (ABK) (Group 3) (Figure 1). All grafts were performed by the same surgeon using a single-torque, running stitch with 16 bites and a corneal button 7.5 mm in diameter. The corneal button was obtained with the punch technique using a Barron威 trephine (Katena Products Inc.). 0886-3350/03/$–see front matter doi:10.1016/S0886-3350(02)01742-X

VISUAL ACUITY AFTER PKP FOR BULLOUS KERATOPATHY

Figure 1. (Schraepen) Twenty-six patients with PBK or ABK divided into the 3 study groups.

In the pseudophakic eyes with a PC IOL, the IOL was left in place and in those with an AC IOL, the IOL was removed during the surgical procedure and replaced by a Worst iris claw lens fixated on the anterior face of the iris. The IOLs were removed because they were too small relative to the width of the anterior chamber. Removing the IOL eliminated the cause of the PBK. Since it is difficult to measure the anterior chamber width in eyes with severe corneal edema, the iris claw lens was used to replace the AC IOL. The Worst iris claw lens was also implanted in the 2 aphakic eyes during the surgical procedure. The following data were recorded: graft survival; age of the patient at the time of surgery; visual acuity before and after surgery, including best corrected visual acuity (BCVA); presence of concomitant ocular pathology viewed by slitlamp examination and fluorescein angiography before and after keratoplasty (in many cases, the latter was not possible before surgery because of the keratopathy); and interval between the initial cataract surgery and the keratopathy.

Figure 2. (Schraepen) Visual acuity before and after PKP in the presence or absence of an IOL and the IOL location in the eye.

who were left aphakic, 90 years. Both were significantly higher than the mean age of patients in Group 1 (74 years) (P ⬍ .05, Student t test) (Table 1). Visual acuity improved in Group 1 (P ⬍ .01, Student t test) (Figure 2). Preoperatively, the visual acuity was better in Group 2 than in Group 1, but the postoperative improvement was less (Table 1). In Group 1, the visual acuity improved in 69% of patients after PKP; it remained unchanged in 31% of patients and did not decrease in any patient (Figure 3). In Group 2, the visual acuity improved in 37.5% of patients, remained unchanged in 37.5%, and decreased in 25.0% (Figure 4). In each group, the visual outcome in the presence of concomitant macular pathology or glaucoma was studied. In Group 1, 69% of patients did not have macular edema or degeneration; 31% presented with concomi-

Results Graft failure occurred in 1 patient (4%) during the 3-year study. The mean age of patients at the time of surgery was 78 years (range 61 to 90 years). The mean age of patients in Group 2 was 84 years and of those

Table 1. Visual outcome of PKP for bullous keratopathy. BCVA Improvement

Mean Age (Y)

0.26

0.23

74

0.14

0.14

0.00

84

⬍0.05

⬍0.05

0.00

90

Group

N

Preop

1 (PC IOL)

16

0.02

2 (AC IOL)

8

3 (Aphakia)

2

Postop

N ⫽ number of patients; BCVA ⫽ best corrected visual acuity

Figure 3. (Schraepen) Visual acuity before and after PKP in Group 1 patients (PC IOL).

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Figure 4. (Schraepen) Visual acuity before and after PKP in Group 2 patients (AC IOL).

tant ocular pathology: macular edema (1 patient), macular degeneration (2 patients), glaucoma (2 patients). In Group 2, all patients presented with concomitant ocular pathology: cystoid macular edema (7 patients) and macular degeneration (1 patient). Aggravation of the preexisting pathology resulted in a worsening of the visual acuity in 25% of Group 2 patients. In eyes without posterior segment pathology, the visual acuity improved from a mean of 0.03 (range 0 to 0.20) to a mean of 0.37 (range 0.03 to 0.90). In eyes with posterior segment pathology, no improvement in visual acuity could be obtained (Table 2). The mean age was similar in both groups (P ⬍ .01, Student t test), suggesting that age is of no prognostic value for visual outcome. The number of patients in Group 3 was small. In both patients, the visual outcome showed no improve-

ment; it was less than 0.05 before and after PKP. Both patients also presented with age-related macular degeneration and glaucoma. Symptomatic bullous keratopathy occurred after a mean interval of 4.3 years (range 0.5 to 12.0 years) after cataract surgery in Group 1 and 11.1 years (range 9 to 17 years) in Group 2. In Group 3, the interval between cataract extraction and symptomatic ABK was 22 years. The best visual recovery occurred in patients in whom bullous keratopathy developed fewer than 3 years after cataract surgery: In 9 of 10 patients, visual acuity improved by 0.15 or more. Although a good recovery could be achieved after 17 years, only 3 of the 16 patients in whom bullous keratopathy developed more than 3 years after cataract surgery had a visual improvement of 0.2 or more (Figure 5).

Discussion Cataract surgery is the major surgical intervention in ophthalmology. It is estimated that more than 1 500 000 cataract extractions are performed annually in the United States.7 In Belgium, the number was approximately 60 000 in each year of the study (National Institute of Social Security, Brussels, Belgium). Since the 1980s, IOLs have been implanted routinely after cataract extraction. Before 1985, AC IOLs were implanted primarily and after 1985, PC IOLs.8,9 At the end of the 1990s, PBK was the most important indication for PKP10 –13 because of the high rate of AC IOL implantation in the 1980s. The indications for PKP are listed in Table 3. Although PBK remains the

Figure 5. (Schraepen) Improvement in visual acuity relative to the interval between cataract surgery and the appearance of bullous keratopathy.

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Table 2. Role of concomitant ocular pathology in visual acuity after PKP in patients with PBK. BCVA

Concomitant Ocular Pathology

N

Preop

Postop

Improvement

Mean Age (Y)

No other pathology present

11

0.03

0.37

0.34

75

Other pathology present

13

0.09

0.09

0.00

79

All patients with PBK

24

0.06

0.21

0.15

77

N ⫽ number of patients; BCVA ⫽ best corrected visual acuity

predominant indication for PKP, most authors report that in the past 5 years its occurrence rate has begun to level off.11 In our study, patients were referred when the painful end stage of PBK had been reached; ie, no medical treatment or surgical technique including PTK was of any help.14 –16 The graft survival rate in our study was 96% (25/26) at 3 years. Waldock and Cook3 report the overall survival rate of corneal grafts as 90% at 1 year, 74% at 5 years, and 62% at 10 years. The survival rate in bullous keratopathy specifically is 51.1% at 10 years.5 Penetrating keratoplasty in patients with secondary endothelial failure or superficial vascularization has the highest risk of graft failure.4 The incidence of bullous keratopathy after cataract surgery is low and does not appear to be higher than 0.3% in a review study conducted by Powe et al.17 Bigar and coauthors18 report the incidence of PBK in patients with a PC IOL to be 0.1% to 0.3% (1980 to 1986). In their study of PKP performed for PBK, Liu and Slomovic19 found an AC IOL in 71.6% of patients and a PC IOL in 16.0%. In our study, 61% of patients had a PC IOL, 31% had an AC IOL, and 8% were aphakic. Powe et al.17 studied visual results after cataract surgery in 17 390 eyes and surgical complications in 68 316 eyes Table 3. Indications for PKP. Indication PBK Keratoconus

Percentage of Patients* 23.0 to 28.5 7.1 to 17.0

Fuchs’ dystrophy

7.6 to 13.9

ABK

6.1 to 10.0

Herpes simplex keratitis

4.2 to 11.7

Posttraumatic

4.0 to 8.5

PBK ⫽ pseudophakic bullous keratopathy; ABK ⫽ aphakic bullous keratopathy *References 10 –13

with AC and PC IOL implantation performed between 1979 and 1991. The visual outcome after cataract surgery was 0.5 or better in 89.7% of all cases. In our series, patients who developed PBK after PC IOL implantation had a visual prognosis of 0.37 if no concomitant ocular pathology was found. This means that although PBK can be treated, visual expectancy decreases significantly with this condition. Patients who developed PBK after AC IOL implantation have an even lower visual recovery expectancy; 0.16 in our series. Besides PBK, Powe et al.17 found the following complications after cataract surgery: CME in 1.5% of patients, endophthalmitis in 0.13%, IOL malpositioning and dislocation in 1.1%, and retinal detachment in 0.7%. Pseudophakic bullous keratopathy is thus the second least common complication after cataract surgery. In cases of PBK, there is a question about what to do with the IOL: remove, replace, or retain? According to Balazs and coauthors,20 the IOL can be retained if its position is adequate and the pupil is mobile. In patients with recurrent hemorrhages, uncontrolled glaucoma, or chronic iritis resistant to medical treatment, the IOL should be removed. Intraocular lens exchange is recommended in cases with closed-loop IOLs, semiflexible AC IOLs, and iris-supported or unstable IOLs as these lenses have been increasingly associated with poor macular function postoperatively. In our study, all AC IOLs were too small relative to the anterior chamber width. We presume these IOLs were not planned preoperatively but became necessary because of a surgical failure, making implantation of a PC IOL impossible. Brunette et al.21 found that implanting a PC IOL at the time of PKP provides better results than an AC IOL; survival of the graft is longer, intraocular pressure is lower, and postoperative visual outcome is better even when the posterior capsule is damaged. In our study, all AC IOLs were replaced by a Worst IOL fixated on the

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anterior face of the iris because sulcus fixation was impossible to perform. In our series, the interval between cataract surgery and PBK was long (4.3 years for PC IOLs and 11.3 years for AC IOLs) compared to the 2-year average in the literature.22,23 We do not know why the patients were referred so late. Although we cannot find a direct causative connection between the type of IOL and the visual prognosis after PKP, we assume that the poorer visual recovery in the AC IOL group was primarily due to posterior segment damage, which occurred in all the patients. There was a significant correlation between the IOL type and posterior segment damage.

Conclusion In this series, the most important positive prognostic factors affecting visual acuity after PKP for bullous keratopathy were the integrity of the posterior segment, a short interval between surgery and the development of bullous keratopathy, and extracapsular cataract extraction with PC IOL implantation. The most important negative prognostic factors were concomitant ocular pathology, an AC IOL, and a long interval between surgery and the development of bullous keratopathy.

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8. Durand L, Burillon C. Les complications de la chirurgie du segment ante´rieur; Socie´te´ franc¸aise d’ophtalmologie. Paris, Masson, 1990; 226 –228 9. Downing JE. Ten-year follow up comparing anterior and posterior chamber intraocular lens implants. Ophthalmic Surg 1992; 23:308 –315 10. Patel NP, Kim T, Rapuano CJ, et al. Indications for and outcomes of repeat penetrating keratoplasty, 1989 – 1995. Ophthalmology 2000; 107:719 –724 11. Flowers CW, Chang KY, McLeod SD, et al. Changing indications for penetrating keratoplasty, 1989 –1993. Cornea 1995; 14:583–5888 12. Haamann P, Jensen OM, Schmidt P. Changing indications for penetrating keratoplasty. Acta Ophthalmol (Copenh) 1994; 72:443–446 13. Mamalis N, Anderson CW, Kreisler KR, et al. Changing trends in the indications for penetrating keratoplasty. Arch Ophthalmol 1992; 110:1409 –1411 14. Thomann U, Niesen U, Schipper I. Successful phototherapeutic keratectomy for recurrent erosions in bullous keratopathy. J Refract Surg 1996; 12:S290 –S292 15. Thomann U, Meier-Gibbons F, Schipper I. Phototherapeutic keratectomy for bullous keratopathy. Br J Ophthalmol 1995; 79:335–338 16. Nagy ZZ, Suveges I, Nemeth J, Fust A. [Phototherapeutic use of excimer laser]. [Hungarian] Orv Hetil 1996; 137(2):75–78 17. Powe NR, Schein OD, Gieser SC, et al. Synthesis of the literature on visual acuity and complications following cataract extraction with intraocular lens implantation. Arch Ophthalmol 1994; 112:239 –252; erratum, 889 18. Bigar F, Stu¨ rmer J, Ganzfried R. Pseudophake bullo¨ se Keratopathie. Klin Monatsbl Augenheilkd 1988; 192: 453–457 19. Liu E, Slomovic AR. Indications for penetrating keratoplasty in Canada, 1986 –1995. Cornea 1997; 16:414 – 419 20. Balazs E, Balazs K, Modis L Jr, Berta A. Penetrating keratoplasty for pseudophakic bullous keratopathy. Acta Chir Hung 1997; 36:11–13 21. Brunette I, Stulting RD, Rinnie JR, et al. Penetrating keratoplasty with anterior or posterior chamber intraocular lens implantation. Arch Ophthalmol 1994; 112: 1311–1319 22. Talor DM, Atlas BF, Romanchuk KG, Stern AL. Pseudophakic bullous keratopathy. Ophthalmology 1983; 90:19 –24; discussion by WS Muenzler, 24 23. Koenig SB, Schultz RO. Penetrating keratoplasty for pseudophakic bullous keratopathy after extracapsular cataract extraction. Am J Ophthalmol 1988; 105:348–353 From the Department of Ophthalmology, University Hospital Antwerp, Antwerp, Belgium. None of the authors has a financial interest in any product mentioned.

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