Incidence of Cataract Extraction After Corneal Transplantation in Young and Middle-Aged Patients

Revathi Naadimuthu, MDGerald W. Zaidman, MDBrandon Mirochnik, BA

Tehara Bailey, BA

Authors have no financial interest to disclose.

New York Medical CollegeWestchester Medical CenterValhalla, NY

Introduction

• In patients requiring corneal transplantation and cataract extraction there is debate as to how it should be performed:– “Triple procedure” - simultaneous cataract

extraction (CE), lens implantation and penetrating keratoplasty (PKP/DSEK)

– Keratoplasty followed by CE with lens implantation

– Cataract extraction followed by keratoplasty

Purpose

• Cataract formation has been found to develop in 24–60% of all patients after a single penetrating keratoplasty.

• This study will: – Determine the incidence of cataract formation in

younger and middle-aged patients, aged 25 – 65 years old, who required penetrating keratoplasty.

– Determine the various risk factors associated with cataract formation.

Methods• A retrospective chart review was performed on 195 penetrating keratoplasty cases

performed by a single surgeon between December 1997 and January 2007 in a tertiary care setting, with an average follow up time of 4 years following corneal transplantation.

• The cases were reviewed for the presence of cataracts following transplant, and the etiologies leading to corneal transplantation.

• The patients were divided into three groups by age– 25-35 years old– 36-50 years old– 51-65 years old

• Each group was then analyzed for incidence of cataract formation– Cataract formation did not occur– Cataract formation occurred

• The factors analyzed were– Preoperative diagnosis– Age– Complications following PKP-rejection, glaucoma, regrafts– Pre-existing lens opacity– Length of time to cataract formation

Results• The most common diagnoses included:

– Keratoconus (65%)– Fuchs' dystrophy (10%)– HSV keratitis leading to corneal scarring (8%)– Other corneal dystrophies (7%)– Trauma (4%)– Post-refractive surgery ectasia (3%)

Results

Age 25-35 (n=58)

KCN 48 (83%)

Trauma 4 (6%)

HSV 2 (3%)

Corneal dystrophy 2 (3%)

Refractive ectasia 1 (2%)

Scar, Ulcer 1 (2%)

Age 36-50 (n=82)KCN 54 (66%)

Dystrophy 8 (10%)

Refractive Ectasia 5 (6%)

HSV 4 (5%)

Trauma 4 (5%)

Ulcer 2 (2%)

Corneal Edema 2 (2%)

Fuchs 2 (2%)

Exposure, scar 1 (1%)

Age 51-65 (n=55)KCN 21 (38%)

Fuchs 17 (31%)

HSV 8 (15%)

Dystrophy 4 (7%)

Corneal Edema 1 (2%)

Ulcer 1 (2%)

Diagnosis Leading to PKP by Age

Results• Incidence of complications

CATARACT FORMATION

NO CATARACT FORMATION

Rejection 37.5% 32%AGE 25-35 IOP 0 2%

Regrafts 0 2% Rejection 42% 29%

AGE 36-50 IOP 6% 2% Regrafts 12% 2% Rejection 24% 17%

AGE 51-65 IOP 8% 0 Regrafts 10% 0

Results

AGE GROUP

PREEXISTING LENS CHANGES

CATARACT EXTRACTION

25-35(n=58) 2 (3%) 1 (1.7%)

36-50(n=82) 6 (7%) 2 (2.4%)

51-65(n=55) 38 (69%) 18 (33%)

Preexisting lens changes leading to cataract extraction

Of all patients, 46% had preexisting cataract, while only 13% went on to require cataract extraction

ResultsDiagnosis No. of Patients Required CE

KCN 132 6 (5%)Fuchs' 19 9 (47%)HSVK 15 8 (53%)

Lattice 12 2 (17%)

CATARACT EXTRACTIONS• Age Group 25-35

– 2 cataract extractions– Both in KCN patients– Average of 4 years to CE (n=2)

• Age Group 36-51– 3 cataract extractions– KCN, HSV, Trauma– Average of 1.4 years to CE (n=3)

• Age Group 51-65– 21 cataract extractions– 9 (53%) of all patients with Fuchs' required

CE– Patients with Fuchs and prior cataracts had

a 64% incidence of CE– 5 (63%) of patients with HSVK required CE– 1 (5%) of patients with KCN required CE– Average 1.98 years to CE (n=21)

Results• The major factors affecting cataract formation were the diagnosis leading to corneal

transplant and age• 47% of patients who formed cataracts had a post-operative complication while complications

were only seen in 36% of patients who did not form cataracts, but this difference was not statistically significant

• Average age was lower in the groups that did not form cataracts vs. those that required CE (37 y.o. vs. 58 y.o.)

• Total Cataract Extractions = 26– 81% were over age 51 – 81% had preexisting lens opacities

• Diagnosis– The most common diagnosis in patients who did not require cataract extraction was KCN– In patients who required cataract extraction, the most common diagnosis was Fuchs'

dystrophy followed by HSV keratitis

Conclusion• The age of the patient was related to incidence of cataract formation

and extraction.

• KCN was associated with the least incidence of cataract formation , while Fuchs Dystrophy followed by HSV keratitis were associated with the highest incidence of cataract formation and extraction.

• Any one complication alone (e.g. history of rejection, high IOP, graft failure requiring a 2nd graft) did not significantly contribute to CE

• Even when controlled for age, patients with Fuchs had a 53% incidence of CE, compared to 5% incidence of CE in patients with KCN

Conclusion• Implications and counseling patients

– Risk of requiring cataract extraction is greatest in patients over age 51 • 33% required cataract extraction• In this population the risk is even greater in patients with a diagnosis of Fuchs' dystrophy

– Risk is also great in patients with a diagnosis of HSV keratitis – 53% incidence of CE

– Complications such as rejection episodes and elevated IOP did not significantly affect the necessity for cataract extraction

Surgeons should be aware that many patients aged 51-65 that require keratoplasty have a chance of needing cataract surgery

1. Martin TP, Reed JW, Legault C, Oberfeld SM, Jacoby BG, Yu DD et al. Cataract formation and cataract extraction after penetrating keratoplasty. Ophthalmology 1994; 101: 113–119.

2. Rathi VM, Krishnamachary M, Gupta S. Cataract formation after penetrating keratoplasty. J Cataract Refract Surg 1997; 23: 562–564.