Penetrating keratoplasty for pseudophakic bullous keratopathy. Management of the intraocular lens

Intraocular lens exchange 1 week after descemet stripping automated endothelial keratoplasty

PURPOSE

To report a case of intraocular lens (IOL) exchange performed 1 week after Descemet stripping automated endothelial keratoplasty (DSAEK).

METHODS

Describe the clinical findings and outcome of IOL exchange in an 80-year-old man with pseudophakic bullous keratopathy and retained Artisan (Ophtec BV, Groningen, the Netherlands) iris-fixated IOL after uneventful DSAEK.

RESULTS

The patient presented on the third postoperative day after DSAEK with disenclavation of the nasal iris claw and inferior dislocation of the IOL. The dislocated IOL was removed and exchanged with an angle-supported open-loop anterior chamber lens 7 days after the initial DSAEK procedure.

CONCLUSIONS

Despite the relatively traumatic intraocular manipulation, the donor tissue was unaffected in its position and clarity. This case demonstrates that successful DSAEK surgery is compatible with additional surgical procedures, even if they are performed in the early postoperative period.

Pseudophakic corneal edema: A review of mechanisms and treatments

PURPOSE

To review the pathological mechanisms and treatments for pseudophakic corneal edema (PCE), one of the most common indications for penetrating keratoplasty.

METHODS

The literature was examined for the molecular biology associated with PCE and for the surgical and medical treatments for this disorder.

RESULTS

The incidence of PCE has recently been decreasing because of improved surgical instrumentation, including improvements in intraocular lens designs that cause less trauma to the corneal endothelium. Extracellular matrix and growth factor abnormalities occur in PCE corneas and recently, the role of aquaporins, which are involved in the regulation of fluid movement across cells, has been investigated.

CONCLUSIONS

Although newer treatment options have been suggested, penetrating keratoplasty still remains the most definitive treatment and has the highest success rate.

Iris-sutured posterior chamber intraocular lens implantation during penetrating keratoplasty

PURPOSE

To evaluate the clinical indications and postoperative results of iris-sutured posterior chamber intraocular lens implants performed during penetrating keratoplasty.

METHODS

Medical records were retrospectively reviewed for preoperative indications and postoperative results of 342 consecutive patients (366 eyes) who underwent iris suturing of a posterior chamber intraocular lens implant during penetrating keratoplasty over a 9-year period.

RESULTS

Mean follow-up was 36 months. The principal indications for corneal transplantation were pseudophakic and aphakic bullous keratopathy. Mean postoperative best spectacle-corrected visual acuity was better than preoperatively at all measured time points (P < 0.0001) and improved from 20/474 preoperatively to 20/85 at 1 year. Nine eyes (7.7%) with known preoperative glaucoma required escalation of therapy by medication or surgery to control the intraocular pressure. Seventy-two eyes (29%) without known preoperative glaucoma required treatment of elevated intraocular pressure. Seventy-nine eyes (28%) without known preoperative cystoid macular edema were additionally diagnosed. Mean endothelial cell counts declined throughout the study time frame. Corneal donor rejection episodes occurred in 36 (9.8%) eyes, with the majority having a single episode. Overall, 27 (7.4%) eyes had known graft failure at last follow-up. Two eyes (0.5%) were enucleated following wound disruption.

CONCLUSIONS

These long-term results of iris-sutured posterior chamber intraocular lens implants performed during penetrating keratoplasty suggest acceptable visual acuity, graft survival, and complication rates. They are similar to published retrospective and prospective results of flexible open-loop anterior chamber and transsclerally-sutured posterior chamber intraocular lens implants placed during penetrating keratoplasty.

Laser in situ keratomileusis for correction of myopia and astigmatism after penetrating keratoplasty

PURPOSE

To determine the safety and effectiveness of laser in situ keratomileusis (LASIK) for visual rehabilitation of residual myopia and astigmatism after penetrating keratoplasty.

DESIGN

Prospective, noncomparative case series.

PARTICIPANTS

LASIK was performed on 23 eyes of 22 patients unable to wear glasses or contact lenses after penetrating keratoplasty due to anisometropia, high astigmatism, and/or contact lens-intolerance.

METHODS

All patients underwent LASIK for visual rehabilitation after penetrating keratoplasty. Uncorrected visual acuity and best spectacle-corrected visual acuity, degree of anisometropia, and corneal transplant integrity were recorded before surgery, as well as at 1 month, 3 months, 6 months, and 12 months after LASIK surgery.

RESULTS

The mean spherical equivalent before surgery was -7.58+/-4.42 diopters (D), which was reduced to -1.09+/-2.01 D, -0.79+/-1.84 D, -0.77+/-1.25 D, and -1.57+/-1.20 D, respectively, at 1, 3, 6, and 12 months after LASIK. The mean cylinder before surgery was 3.64+/-1.72 D, which was reduced to 1.98+/-1.15 D, 1.64+/-1.14 D, 1.48+/-0.92 D, and 1.29+/-1.04 D, respectively, at 1, 3, 6, and 12 months after LASIK. Spherical equivalent anisometropia was reduced from a mean of 6.88+/-4.4 D to 1.42+/-1.05 D at the final examination. Best-corrected visual acuity remained the same or improved in 21 of 23 eyes and decreased by 1 and 3 lines in 2 patients. There were no surgical flap or corneal transplant complications.

CONCLUSIONS

LASIK is a viable treatment alternative for myopia and astigmatism after penetrating keratoplasty in patients who are contact lens-intolerant. LASIK is more effective in treating myopia than astigmatism after penetrating keratoplasty.

Intraocular lens complications requiring removal or exchange

Intraocular lens (IOL)-related complications are caused primarily by mechanical trauma, inflammatory or infectious complications, or optical problems. Complications may occur at the time of surgery or be the result of an ongoing postoperative process. Mechanical and inflammatory injury may produce corneal decompensation, cystoid macular edema, hyphema, uveitis, and glaucoma, causing reduced vision and in some cases chronic pain. Optical problems may be due to a wrong power of the IOL or to postoperative decentration or dislocation of the lens. Ophthalmologists should be aware of the indications for IOL removal or exchange in those patients who have ongoing IOL-induced injury or impairment. Removal or exchange of an IOL frequently involves a complex decision-making process and is often associated with immense technical challenge. Various medical and surgical treatments may be tried to correct IOL problems before the decision is made to remove or exchange the lens.

Ulcerative keratitis in bullous keratopathy

PURPOSE

The authors review a large series of patients with bullous keratopathy (BK) to analyze the frequency of ulcerative keratitis, and determine the contributory roles of bullae, bandage soft contact lenses, steroids, and prophylactic antibiotics.

METHODS

A retrospective review of all cases of pseudophakic or aphakic bullous keratopathy presenting to the cornea service between January 1, 1986 and September 1, 1995 was performed. The influence of time, bullae, bandage contact lenses, steroids, and prophylactic antibiotics was evaluated by actuarial methods and multivariate analysis.

RESULTS

Nine hundred eighteen patients were included in this study, 44 (4.7%) of whom had infectious or inflammatory complications; 813 cases were available for statistical analysis. Steroids (P < 0.0001), bandage soft contact lens use (P = 0.004), and bullae (P = 0.01) had statistically significant independent effect on the risk of developing ulcerative keratitis, and the combination of steroids and bandage lenses yielded the highest risk (P < 0.001). Propylactic antibiotic use paradoxically had a statistically significant association with ulcerative keratitis in these patients (P = 0.01). Increasing BK time was also associated with ulcer development, and the risk remained relatively constant over the 60 months of the study. Streptococcus was the most frequent organism cultured.

CONCLUSIONS

Ulcerative keratitis developed in 4.7% of patients with bullous keratopathy. Prolonged BK time alone was a risk factor for infection. The strongest single additional risk factor for ulcer development was steroid use, followed by bandage soft contact lens use, and their simultaneous use had the greatest effect. The presence of bullae was also a risk factor for infection, and prophylactic antibiotic use did not prevent ulcer development.

Preoperative ultrasound biomicroscopy to assess ease of haptic removal before penetrating keratoplasty combined with lens exchange

PURPOSE

To evaluate a method of assessing anterior chamber intraocular lens (IOL) haptics before combined penetrating keratoplasty and IOL exchange in eyes with poor corneal clarity resulting from pseudophakic bullous keratopathy (PBK).

SETTING

Department of Ophthalmology, Toronto Hospital, Ontario, Canada.

METHODS

Twelve eyes (25 haptics) with PBK were studied using ultrasound biomicroscopy (UBM). The degree of haptic encasement was graded. The result was compared with the degree of difficulty and the complications encountered in removing the IOL at the time of surgery. The surgeons were masked as to the UBM results.

RESULTS

All haptics were easily visualized with UBM, with 23 in the angle and 2 passing through a peripheral iridectomy. On UBM, 9 haptics were noted to lie free in the angle, and 16 were encased by fibrotic tissue. Eight were covered by less than 100 microns and 8 by more than 100 microns of tissue. Calculations using Kappa statistics found a strong predictive value for the UBM in identifying the presence or absence of fibrotic encasement and degree of difficulty in removing the anterior chamber IOL haptics. Ultrasound biomicroscopy also allowed assessment of the adjacent angle for synechias.

CONCLUSION

Ultrasound biomicroscopy provides an alternative method for evaluating anterior chamber IOL haptics when gonioscopy is not possible because of corneal opacity. This method allows the surgeon to predict preoperatively the degree of difficulty that will be encountered in explanting the IOL.

Penetrating keratoplasty and transscleral fixation of posterior chamber lens

We reviewed the charts of 21 patients who underwent penetrating keratoplasty and transscleral fixation of a posterior chamber lens. One lens was sutured in an aphakic eye and 20 lenses were sutured after removal of an anterior chamber lens. Postoperative follow-up averaged 13 months (2-39 months). Visual acuity improved in 20 patients (95%) and remained the same in 1 patient (5%). Postoperative visual acuity was less than 0.1 in 5 patients (23.8%), 0.1 to 0.33 in 14 patients (66.7%) and better than 0.33 in 2 patients (9.5%). Twelve patients (57.1%) expressed a substantial reduction in ocular pain, 7 patients (33.3%) had no pain either before or after the operation, 2 patients (9.5%) expressed no reduction in pain. No cases of endophthalmitis, choroidal hemorrhage or retinal detachment were found. In one case, the sutured lens was dislocated without disturbing vision. Intraocular pressure increased in 3 of 9 patients with preoperative glaucoma. New-onset glaucoma developed in 1 patient. We find transscleral fixation of a posterior chamber lens to be an acceptable procedure in penetrating keratoplasty with IOL implantation where capsular support is inadequate for conventional implantation of a posterior chamber lens.

Combined pars plana vitrectomy-lensectomy and open-loop anterior chamber lens implantation

PURPOSE

To investigate the effectiveness of open-loop, one-piece, flexible, Kelman-style, all-polymethylmethacrylate (PMMA) anterior chamber intraocular lenses (AC IOLs) in patients undergoing pars plana vitrectomy surgery for a variety of vitreoretinal disorders.

METHODS

Fifteen patients (6 women and 9 men) underwent combined pars plana vitrectomy with insertion of an open-loop AC IOL. Postoperative results were evaluated.

RESULTS

The average preoperative visual acuity of 20/360 (logMAR scale, 1.25 +/- 0.80) improved to 20/52 (logMAR scale, 0.42 +/- 0.35) after an average follow-up of 10.2 months (range, 1-41 months). Of 15 eyes, 7 (47%) achieved a visual acuity of better than 20/40. There was no evidence of glaucoma exacerbation or corneal decompensation. Visual acuity was limited primarily by chronic cystoid macular edema in 4 (27%) of 15 eyes.

CONCLUSION

In this preliminary series of patients, open-loop, flexible, all-PMMA, Kelman-style AC IOLs appear to be well tolerated and represent a viable, simple alternative to transscleral fixation of a posterior chamber IOL or surgical aphakia in patients undergoing vitrectomy surgery.

Back to front AC IOL implantation combined with penetrating keratoplasty

In this retrospective study a simple modification of implanting an intraocular lens into the anterior chamber during penetrating keratoplasty is presented. In 14 patients who underwent penetrating keratoplasty after cataract extraction, the intraocular lens was placed back to front in the anterior chamber so that the haptic was angled anteriorly. Postoperative follow-up was 18 months on the average. There was significant improvement in vision. All 9 patients with painful bullous keratopathy were relieved of their pain. One case of mild, transient uveitis and glaucoma and two dilated pupils were seen postoperatively. No major complications have been observed so far. This study suggests that this simple method, in some cases, might be favourable when implanting an intraocular lens during penetrating keratoplasty, in the absence of capsular support.

A randomized trial of intraocular lens fixation techniques with penetrating keratoplasty

PURPOSE

Pseudophakic corneal edema is the principal indication for penetrating keratoplasty in the United States. Currently, three techniques of intraocular lens (IOL) fixation during penetrating keratoplasty for this condition are commonly used--flexible anterior chamber IOL (AC IOL) implantation, iris suture fixation of a posterior chamber IOL (PC IOL), and transscleral suture fixation of a PC IOL. This study represents the first prospective, randomized comparison of these three techniques.

METHODS

One hundred seventy-six consecutive patients with pseudophakic corneal edema who underwent penetrating keratoplasty with IOL exchange were randomized to one of the three implantation techniques. Standardized evaluations were performed at baseline and at 6, 12, and 18 months postoperatively. Life-table analysis provided cumulative risk estimates for specific complications.

RESULTS

Randomization produced comparable groups at baseline. The cumulative risk of macular edema was significantly less for the iris fixation cohort than for either the AC IOL or scleral fixation group. A complications index was constructed based on the major adverse outcomes of glaucoma escalation, cystoid macular edema, IOL dislocation, and graft failure. A significantly lower risk of complication was found for iris compared with scleral fixation of PC IOLs.

CONCLUSION

The authors conclude that transscleral fixation of the PC IOL at the time of penetrating keratoplasty for pseudophakic corneal edema is associated with a greater risk of adverse outcome than iris fixation of a PC IOL.

Intraocular lens exchange for anterior chamber intraocular lens-induced corneal endothelial damage

BACKGROUND

Anterior chamber and iris-plane intraocular lenses (IOLs) have been implicated in causing corneal endothelial damage and progression to pseudophakic bullous keratopathy.

METHODS

The authors performed IOL exchanges on 102 eyes with signs of early corneal decompensation or progressive endothelial cell loss associated with these anterior chamber or iris-plane IOLs. Replacement IOLs were posterior chamber lenses sutured to the iris (87 eyes), sutured to the sclera (3 eyes), or placed in the ciliary sulcus (12 eyes).

RESULTS

Seventy-two eyes (71%) had the same or improved vision after a mean follow-up period of 18.6 months (range, 6 to 60 months). Only 24 eyes (23.5%) progressed to corneal decompensation. Of the eyes that decompensated, 75% had preoperative endothelial cell counts of 500 cells/mm2 or less (P < 0.0001), and 83% had preoperative signs of early corneal decompensation (P < 0.001). Biomicroscopic signs of early corneal decompensation seen preoperatively in 50 eyes resolved in 17 eyes (34%) and remained unchanged in 12 eyes (24%) at the last postoperative follow-up visit.

CONCLUSION

Removal of anterior chamber and iris-plane intraocular lenses in eyes showing signs of endothelial damage may prevent progression to pseudophakic bullous keratopathy if performed before a critical degree of endothelial cell loss or dysfunction has developed.

Penetrating keratoplasty and transscleral fixation of posterior chamber lens

We reviewed the outcome in 115 patients who underwent penetrating keratoplasty and transscleral fixation of a posterior chamber lens. One patient died soon after surgical procedures, and nine patients were lost to follow-up, leaving a cohort of 105 patients. Mean follow-up time was 26.8 months (range, six to 43 months). Visual acuity of 20/40 or better was found in 29 patients (27.6%) and 20/50 to 20/200 in 37 patients (35.2%). Reasons for poor visual outcome included cystoid macular edema in ten patients (9.5%), age-related macular degeneration in six patients (5.7%), and retinal detachment in four patients (3.8%). None of the patients developed lens decentration. There were no instances of hyphema and only one patient had a perioperative limited suprachoroidal hemorrhage. New-onset increase in intraocular pressure developed in 20 of 66 patients (30.3%). Analysis of the 39 patients with preoperative increase in intraocular pressure that required medical treatment demonstrated an improvement in 13 patients (33.3%), worsening in 12 patients (30.8%), and unchanged status in 14 patients (35.9%). The exposed haptic suture was covered by using one of the following three alternative methods: a conjunctival flap, a scleral flap, or a corneal tissue button. Exposure of the haptic suture through the conjunctiva was a complication in 21 patients (20%). Of these 16 (76.1%) occurred in the group with a conjunctival covering, five (23.8%) occurred in the group with a scleral flap, and none occurred in the corneal tissue button group. This study demonstrated that transscleral fixation of a posterior chamber lens is a viable option in the treatment of patients undergoing penetrating keratoplasty and intraocular lens implantation with absent capsular support.

Soemmering's ring support for posterior chamber intraocular lens implantation during penetrating keratoplasty. Changing trends in bullous keratopathy

BACKGROUND

Changing trends in cataract extractions have resulted in a new category of bullous keratopathy: corneal decompensation after complicated extracapsular cataract extraction. These cases of bullous keratopathy are associated with rupture of the posterior capsule, vitreous loss, and significant intraocular inflammation at the time of the original complicated extracapsular cataract extraction.

METHODS

The authors reviewed 14 consecutive cases of penetrating keratoplasty for bullous keratopathy in which posterior chamber intraocular lens implantation was supported by remnants of the posterior capsule and/or Soemmering's ring without suture fixation. All 14 patients had a history of complicated extracapsular cataract extraction with capsule rupture and vitreous loss.

RESULTS

All 14 patients had clear, compact grafts without migration of the intraocular lens with a mean follow-up of 12.1 months. Vision improved in 93% of cases, and there was no significant worsening of glaucoma.

CONCLUSIONS

Pseudophakic bullous keratopathy after traumatic extracapsular cataract extraction with an anterior chamber intraocular lens and aphakic bullous keratopathy after traumatic extracapsular cataract extraction are two relatively new clinical entities that present new intraocular lens management options. Bullous keratopathy after complicated extracapsular cataract extraction should be recognized as a distinct clinical entity. Intraocular lens implantation into the ciliary sulcus with Soemmering's ring and peripheral capsular support provide the advantages of a posterior chamber intraocular lens without the risk of iris or scleral sutures. The authors predict that bullous keratopathy associated with traumatic extracapsular cataract extraction will become one of the more common indications for penetrating keratoplasty.

Indications for and results of intraocular lens explantation

We reviewed the medical records of 97 patients who had 101 consecutive intraocular lens (IOL) explantation procedures, with or without exchange, at the University of Florida Eye Center from January 1, 1983, to December 31, 1987. The majority of the removed IOLs were anterior chamber styles (53.9%), followed by iris-fixated lenses (33.7%). The most common indications for surgery included pseudophakic bullous keratopathy (PBK)--69%, uveitis-glaucoma-hyphema (UGH) syndrome--9%, and IOL instability--7%. The best visual outcome was seen in patients with IOL instability; 50% achieved 20/40 or better visual acuity. Forty one percent of patients with PBK, who had IOL explantation/exchange combined with penetrating keratoplasty, achieved 20/40 or better visual acuity. The poorest visual outcome was seen in patients with the UGH syndrome; 83% had a final acuity of 20/200 or worse. However, these patients achieved resolution of their pain and inflammation and better control of their intraocular pressure as a result of the surgery. Complications leading to IOL explantation tended to occur months to years after the original surgery in patients with closed-loop, semi-flexible anterior chamber lenses and iris-fixated lenses. Posterior chamber lenses were most often removed because of complications unrelated to the implant.

Implantation of Kelman-style, open-loop anterior chamber lenses during keratoplasty for aphakic and pseudophakic bullous keratopathy. A comparison with iris-sutured posterior chamber lenses

The clinical and specular microscopic results of 40 cases (39 patients) of penetrating keratoplasty during which a Kelman-style anterior chamber intraocular lens was implanted were reviewed retrospectively. Thirty-one pseudophakic eyes received an intraocular lens exchange and nine aphakic eyes received a secondary intraocular lens. Postoperative follow-up averaged 24.5 months (range, 3 to 51 months). At 1, 2, and 3 years after keratoplasty, 39.3%, 63.2%, and 63.6% of eyes, respectively, had visual acuities of 20/40 or better. Ninety-five percent of the grafts remained clear. Causes of poor postoperative visual acuity included cystoid macular edema (32.5%), new glaucoma (22.5%), and age-related macular degeneration (10.0%). Other causes were endothelial rejection leading to graft failure, corneal ulceration, and retinal detachment. Corneal endothelial cell loss by specular microscopy was 11.5% at 1 years, 21.3% at 2 years, and 25.0% at 3 years. These results were compared with cell loss associated with iris-sutured posterior chamber lenses in penetrating keratoplasty. Visual outcomes and complication rates were similar between these two methods; however, the endothelial attrition at 1 and 2 years for the sutured posterior chamber lens was greater than that of the Kelman anterior chamber lens.

Graft survival in four common groups of patients undergoing penetrating keratoplasty

Graft survival rates and causes of graft failure were evaluated for 1046 consecutive keratoplasties in four groups: keratoconus, Fuchs' dystrophy, pseudophakic bullous keratopathy with retained intraocular lenses (IOLs), and pseudophakic/aphakic bullous keratopathy with secondary lens implants. Patient follow-up averaged 23 months (range, 1-84 months). There was a significant difference in graft survival among the four groups, P less than 0.0001. The keratoconus and Fuchs' groups had the highest survival rates and pseudophakic bullous keratopathy with retained IOLs the lowest rate. Problems with the external surface of the graft caused the largest number of graft failures. Grafts for pseudophakic bullous keratopathy with retained posterior chamber lenses had a significantly higher failure rate from rejection and endothelial decompensation, 5.1%, compared with less than 1.0% in keratoconus, Fuchs' dystrophy, or bullous keratopathy with secondary implants (P less than 0.0005).

Indications for and outcomes of repeat penetrating keratoplasty

We reviewed data on 150 repeat corneal transplants performed between 1983 and 1988 at Wills Eye Hospital. Minimal postoperative follow-up was six months. The most common diagnoses before regraft were pseudophakic bullous keratopathy (29 of 150), aphakic bullous keratopathy (28 of 150), Fuchs' dystrophy (21 of 150), failed graft (17 of 150), and keratoconus (14 of 150). Herpes simplex keratitis, interstitial keratitis, chemical burns, traumatic scars, and corneal dystrophies accounted for most of the remaining regrafts. Of the 150 regrafts, 39 (26%) failed during the study period. Almost half of the regraft failures occurred within six months, and over four fifths occurred within 18 months. Of the 111 eyes with clear grafts, final visual acuity data were available for 68 eyes (minimal follow-up, two years; mean, 3.3 years). A best-corrected visual acuity of 20/20 to 20/40 (22 of 68) or 20/50 to 20/100 (27 of 68) was achieved in most patients.

A prospective study on the implantation of anterior chamber intraocular lenses during keratoplasty for pseudophakic and aphakic bullous keratopathy

Between April 1986 and April 1989, the authors conducted a prospective study of the use of open-loop anterior chamber intraocular lenses (AC IOLs) in patients undergoing penetrating keratoplasty for pseudophakic bullous keratopathy or monocular aphakic bullous keratopathy. All patients underwent the same operation--a penetrating keratoplasty combined with insertion of an open-loop AC IOL. Pseudophakic patients had an IOL exchange at the time of surgery. Thirty-six patients have been followed an average of 15 months. Thirty-two (89%) of the grafts are clear. Preoperatively, 100% of eyes had visual acuity less than 20/200. Postoperatively, 11 eyes (31%) have visual acuity better than 20/40 and 23 eyes (64%) have visual acuity better than 20/100. The most common causes for visual acuity less than 20/200 were cystoid macular edema, glaucoma, and immunologic graft failure. Using open-loop AC IOLs in patients with pseudophakic or aphakic bullous keratopathy can give good postoperative results and functional vision.

Penetrating keratoplasty for pseudophakic bullous keratopathy associated with closed-loop anterior chamber intraocular lenses

Closed-loop anterior chamber intraocular lenses (AC IOLs) are associated with a high incidence of pseudophakic bullous keratopathy (PBK). The prognosis for recovery of vision with penetrating keratoplasty and the exchange of one type of AC IOL for another remains controversial. A total of 40 consecutive patients with closed-loop AC IOLs and varying degrees of PBK underwent penetrating keratoplasty, explanation of the closed-loop AC IOL, and implantation of a flexible tripod AC IOL--all done with a uniform technique. The average follow-up study was 24 months. Average preoperative visual acuity was 20/170 (range, 20/25-hand motions) and average postoperative visual acuity was 20/44 (range, 20/20-no light perception). A total of 23 eyes (57.5%) achieved a visual acuity of 20/40 or better. Eleven eyes (27.5%) had a visual acuity of 20/200 or worse. Persistent cystoid macular edema was the most frequent cause of poor vision postoperatively (4 eyes), followed by age-related macular degeneration (3 eyes) and graft rejection (2 eyes). This is the first series documenting a good visual outcome for at least 2 years after penetrating keratoplasty and exchange of a closed-loop AC IOL for a single type of flexible tripod AC IOL.

Graft failure after penetrating keratoplasty

Despite the improving results that have been noted with penetrating keratoplasty, graft failure remains a significant problem. The causes of graft failure are quite varied. Primary donor failure, surgical complications, intraocular lens complications, persistent epithelial defects, allograft rejection, infection, glaucoma, trauma, and recurrences of primary corneal dystrophies are common etiologies. In this article, a critical review of the available literature concerned with the factors influencing the many causes of graft failure and their management is provided.

Natural history of cystoid macular edema in pseudophakic bullous keratopathy

A retrospective review of 25 consecutive patients having penetrating keratoplasty (PKP) with the preoperative diagnoses of pseudophakic bullous keratopathy (PBK) and cystoid macular edema (CME) was undertaken to analyze the natural history of preoperative CME following keratoplasty. Follow-up ranged from 13 to 54 months with a mean of 27 months. All patients had intraocular lens exchanges with 24 receiving posterior chamber lenses; 23 had lenses sutured to the posterior iris. Sixteen patients (64%) recovered a visual acuity of 20/40 or better. The average time for visual recovery to 20/40 was nine months with a range of two to 45 months. Eighteen (72%) had resolution of angiographic CME. Three patients previously diagnosed as having chronic CME recovered visual acuity of 20/40 or better. Cases of PBK with CME may have an excellent visual prognosis if the IOL is managed properly at the time of PKP.

Clinical indications for and procedures associated with penetrating keratoplasty, 1983-1988

We reviewed the preoperative clinical indications and associated surgical procedures for 2,299 penetrating keratoplasties performed at our institution from 1983 through 1988. Pseudophakic bullous keratopathy was the most common indication overall, accounting for 526 cases (23%). A marked increase was noted in the incidence of pseudophakic bullous keratopathy as an indication for penetrating keratoplasty beginning in 1985. The association of anterior chamber intraocular lenses in eyes with pseudophakic bullous keratopathy undergoing penetrating keratoplasty increased from 19 of 43 cases (44%) in 1983 to 79 of 108 cases (73%) in 1988. The incidence of intraocular lens exchange at the time of penetrating keratoplasty in cases of pseudophakic bullous keratopathy increased from six of 43 (14%) in 1983 to 63 of 108 (58%) in 1988. Other major indications for penetrating keratoplasty included Fuchs' dystrophy (375 cases, 16%), keratoconus (348 cases, 15%), aphakic bullous keratopathy (331 cases, 14%), and regraft (233 cases, 10%). Cataract extraction, with or without intraocular lens implantation, was combined with penetrating keratoplasty in 397 of 1,532 phakic eyes (26%). The incidence of triple procedure (penetrating keratoplasty, cataract extraction, and intraocular lens implantation) increased from 27 of 248 phakic eyes (11%) in 1983 to 68 of 258 phakic eyes (26%) in 1988.

Visual results of suture-fixated posterior chamber lenses during penetrating keratoplasty

Between August 12, 1982, and June 30, 1987, 233 consecutive eyes had posterior chamber intraocular lenses (PC IOLs) suture-fixated to the posterior aspect of the iris during penetrating keratoplasty (PKP). In all cases, insufficient capsular material was present to provide adequate fixation for the implant. Lenses were placed in 72 aphakic eyes as a secondary implant, and 159 lenses were placed after removal of another implant. Follow-up ranged from 1 year to 68 months with 59.5% of patients achieving visual acuity of 20/40 or better, and 74% of 20/80 or better. Suture-fixating a PC IOL to the iris offers multiple advantages over placement of an anterior chamber lens during PKP. The complication rate appears low, and long-term problems with glaucoma and recurrent corneal decompensation should be reduced.

Comparison of corneal storage in K-Sol and chondroitin sulfate corneal storage medium in human corneal transplantation

Fifty-one pairs of corneas, stored in either K-Sol or CSM (chondroitin sulfate corneal storage medium) from 8 to 97 hours (mean +/- standard deviation, 58 +/- 21 and 57 +/- 21 hours, respectively), were transplanted in a prospective, randomized manner into 99 patients (n = 102 eyes), paired by diagnostic group and procedure. Ninety-six percent of K-Sol grafts (n = 51) and 94% of the CSM grafts (n = 51) were clear at 6 months; 92% of both the K-Sol (n = 38) and CSM (n = 35) grafts were clear at 12 months. One primary donor failure occurred, a K-Sol cornea stored for 76 hours. The CSM group experienced a greater number of persistent epithelial defects beyond 2 weeks (7 versus 4 defects) and graft reaction episodes (7 versus 3 episodes) than the K-Sol group; however, an equal number of late graft failures (3) occurred in both groups. No significant differences by paired t test analyses were found in endothelial cell density, area, coefficient of variation, or figure coefficient at 3 (n = 37 pairs), 6 (n = 36 pairs), and 12 (n = 26 pairs) months between the two groups. Mean endothelial cell density significantly decreased by 11% +/- 22 by 3 months in the K-Sol group, whereas the 7% +/- 24 decrease in the CSM group was insignificant. By 12 months, both groups experienced a significant decrease: K-Sol, 27% +/- 22; CSM, 17% +/- 26. A significant decrease in the mean coefficient of variation (polymegathism) was noted after 3 months in the K-Sol group which returned to the preoperative mean by 1 year, whereas this parameter remained unchanged in the CSM group. Both chondroitin sulfate-based media result in successful corneal transplantation with storage up to 4 days; however, endothelial survival with both media are comparable with previous studies with McCarey-Kaufman (M-K) medium.