Specular microscopic follow-up of corneal grafts for pseudophakic bullous keratopathy

Pseudophakic bullous keratopathy (PBK) has become the leading indication for penetrating keratoplasty. In our initial fifty patients having keratoplasty for PBK there was gradual loss of clear grafts in patients with retained intraocular lenses (IOLs). Specular microscopy was performed on donor tissue, and periodically postoperatively, for 130 grafts for PBK. The highest cell loss at one year was in eyes with retained iris support (39.2%) or anterior chamber (37.2%) IOLs. Cell loss in grafts with removed iris support IOLs (21.3%) was significantly less. When iris support IOLs were exchanged for anterior chamber (AC) IOLs, the cell loss at one year (27.1%) was intermediate. We recommend that iris support IOLs be removed at keratoplasty. Exchange for an AC IOL should be considered depending on the visual needs of each patient. Removal of AC IOLs should be based on consideration of prior tolerance and position of the implant.     

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

Management of the intraocular lens (IOL) at the time of penetrating keratoplasty (PK) for pseudophakic bullous keratopathy has been based on lens-related factors and coexisting anterior segment abnormalities. The authors reviewed the results of PK for 102 cases of pseudophakic bullous keratopathy (43 anterior chamber, 50 iris-supported, and 9 posterior chamber) with respect to: (1) the type of IOL, (2) coexisting abnormalities, and (3) management of the IOL at surgery. Graft failure after 2 years of follow-up was: (1) retained iris-supported IOLs, 9%; (2) retained anterior chamber IOLs, 60%; (3) retained posterior chamber intraocular lenses (PC IOL), 0%; (4) removed IOLs, 9%; and (5) exchanged IOLs, 20%. After 5 years of follow-up, 13 of 13 PKs with retained closed-loop anterior chamber IOLs had failed. Visual results were best in eyes with retained iris-supported, rigid anterior chamber or PC IOLs and when the IOL was removed without replacement. The authors recommend that closed-loop anterior chamber lenses and unstable lenses of any type be removed or exchanged and that well-fixated PC IOLs and iris-clip IOLs be retained at the time of PK for pseudophakic bullous keratopathy.     

人工晶体取出的原因分析

回顾性分析２５例人工晶体取出的原因。其中前房型４例，后房型２１例。前房型和后房型人工晶体从植入至取出的平均间隔时间分别为２３．５和７．１个月。前房型取出的原因为ＵＧＨ综合征３例和人工晶体大泡性角膜病变１例；后房型取出的原因有人工晶体脱位或半脱位１２例，人工晶体大泡性角膜病变４例，人工晶体视网膜脱离３例和眼内炎２例。手术方法：直接取出或合并三切口闭台式玻璃体切除，穿透性角膜移植，玻璃体视网膜手术，前段玻璃体切除和瞳孔膜切除。术后绝大多数眼的视力提高或保持不变。     

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.     

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.     

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.     

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.     

Penetrating keratoplasty 1981-1988: clinical indications and pathologic findings

We analyzed 740 penetrating keratoplasty specimens received at the Intermountain Ocular Research Center from 1981 through 1988. These corneal specimens were categorized by clinical indications for removal and pathologic confirmation of the clinical findings. Keratoconus was the most common indication for a penetrating keratoplasty (22.8%). This was closely followed by pseudophakie bullous keratopathy (21.8%), regraft (13.2%), scarring (8.9%), aphakic bullous keratopathy (6.4%), and Fuchs' endothelial dystrophy (5.8%). Since 1984, pseudophakic bullous keratopathy has surpassed keratoconus as the most common indication for penetrating keratoplasty (27.3% vs. 20.2%). Pseudophakic bullous keratopathy was found more commonly than keratoconus in each of the last four years of this study. The most common type of intraocular lens associated with pseudophakic bullous keratopathy was an anterior chamber lens (52.8%), with iris-fixated (26.7%) and posterior chamber (17.4%) lenses seen less frequently.     

Visual acuity after penetrating keratoplasty for pseudophakic and aphakic bullous keratopathy

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. CONCLUSIONS: 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.     

人工晶体的取出

报告３２例人工晶体取出的经验。取出的原因是人工晶体脱位、持续性非感染性葡萄膜炎，大泡性角膜病变，人工晶体表面膜形成，葡萄膜炎－－青光眼－－前房出血综合征，细菌性眼内炎、人工晶体度数不当和青光眼。     

Changing indications for penetrating keratoplasty in Taiwan from 1987 to 1999

PURPOSE: To determine the leading indications for penetrating keratoplasty and to identify changing trends in these indications during the past 12 years. METHODS: We retrospectively performed a chart review of the hospital records of all patients undergoing penetrating keratoplasty at the National Taiwan University Hospital during a 12-year period (1987-1999). When possible, the clinical indication was corroborated by the pathologic report. RESULTS: A total of 770 corneal transplants were performed. The leading indications for penetrating keratoplasty. in order of decreasing frequency, were corneal scars (27.9%), regraft (21.0%), acute necrotizing and ulcerative keratitis (17.9%), pseudophakic or aphakic bullous keratopathy (17.6%), Fuchs' dystrophy (4.5%), and keratoconus (2.5%). A trend of increasing frequency of regraft and acute necrotizing and ulcerative keratitis, a decreasing frequency of corneal scar, and an initially decreasing then increasing frequency of pseudophakic and aphakic bullous keratopathy were found during the 12-year study period. Acute necrotizing and ulcerative keratitis was found to be the most frequent indication for regraft. CONCLUSION: In this series, corneal scars, regraft, and acute necrotizing and ulcerative keratitis were the leading indications for penetrating keratoplasty. A changing incidence of pseudophakic and aphakic bullous keratopathy noted during the study period was related to the type of intraocular lens implanted and the method of cataract surgery performed. This study found a comparatively high frequency of acute necrotizing and ulcerative keratitis and an extremely low frequency of keratoconus compared with previous reports.     

Anterior chamber and sutured posterior chamber intraocular lenses in eyes with poor capsular support

PURPOSE: To compare the clinical outcomes and complications of patients who had surgical placement of anterior chamber (AC IOLs) and sutured posterior chamber intraocular lenses (PC IOLs) after cataract surgery resulting in poor capsular support. SETTING: Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida. METHODS: A retrospective interventional comparative case series of 181 eyes of 181 patients that had implantation of an intraocular lens with inadequate capsular support was conducted. A chart review of all patients that had implantation of AC IOLs or sutured PC IOLs at a tertiary care eye hospital between 1995 and 2001 was conducted. RESULTS: Outcome measures included final best-corrected visual acuity, spherical equivalent, and postoperative complications (pseudophakic bullous keratopathy, elevated intraocular pressure [IOP] inflammation, retinal detachment, suture erosion, cystoid macular edema). Of 702 charts reviewed, 181 were found to fit inclusion and exclusion criteria. The postoperative complication risk ratio was 0.80 (95% confidence interval [CI]: 0.52-1.23) for AC IOLs compared with PC IOLs. The most common complication experienced by patients having implantation of either lens type was elevated IOP (AC IOL: 38%; PC IOL: 42%). The incidence of other complications was similar between the groups. Best-corrected visual acuity was similar; however, final spherical equivalent trended toward more myopic values in the PC IOL group (-0.82 +/- 1.67 for AC IOL versus -1.32 +/- 2.12 for PC IOL). CONCLUSIONS: The findings suggest that no significant differences in outcome exist when comparing AC IOLs to sutured PC IOLs in complicated cataract extraction with poor capsular support. Recent advances in AC IOL design have yielded lenses that provide a safe, effective alternative to sutured PC IOLs.     

角膜移植适应症的变迁

1975年至1989年间共施角膜移植1963眼次,以单疱性角膜炎、角膜白斑、角膜变性、角膜热化学烧伤及化脓性角膜炎为主要,共1549眼次,占全部角膜移植的78.9%。15年来逐渐减少的是角膜白斑和化脓性角膜炎,明显增多的是再移植和角膜变性。随着角膜移植适应症的扩大,白内障手术的普及和人工晶体植入术的开展,今后再移植和大泡性角膜病变将会进一步增多。     

Intraocular lens removal during penetrating keratoplasty for pseudophakic bullous keratopathy

Pseudophakic bullous keratopathy is now the most common reason for penetrating keratoplasty. In previous reports, the type of intraocular lens (IOL) most frequently encountered in these eyes was the iris plane IOL. The authors reviewed 27 cases of IOL removal during penetrating keratoplasty. Lenses were removed if they were dislocated or associated with iritis, recurrent hyphema, glaucoma, or persistent cystoid macular edema. The IOL encountered most often was the anterior chamber lens (in 22 eyes); closed thin loop, semiflexible or flexible anterior chamber lenses accounted for 19 of these. Iris plane lenses were removed from five eyes. No posterior chamber lenses were removed. Clear grafts were obtained in 24 of 27 cases (89%); visual acuity improved or remained the same in 24 cases, to 20/60 in 11 cases. The most common causes of poor postoperative vision were retinal disease (6/27 cases) and glaucoma (6/27 cases). The association between anterior chamber lenses and pseudophakic bullous keratopathy is probably the result of both the increase in use of these lenses and the documented propensity of the closed loop semiflexible anterior chamber lenses to cause complications.     

Pseudophakic bullous keratopathy

Pseudophakic bullous keratopathy (PBK) is a relatively new disease that is rapidly becoming the prime indication for penetrating keratoplasty. From 1977 thru 1981 we performed 81 corneal transplants on 66 eyes for this condition. In our experience, the incidence of PBK, with iris-supported lenses, is five times greater than aphakic bullous keratopathy (ABK). A series of 800 intracapsular cataract extractions (ICCE) with implantation of iris-supported lenses (1975-1979) were reviewed. Thirty-four patients (4.3%) developed PBK (average two years after surgery). In a series of 3,000 simple ICCEs (1955-1980), 24 patients (0.8%) developed ABK. Etiologic factors, methods of prevention, and the results of penetrating keratoplasty are considered. PBK following ICCE is a serious disease entity, usually of multifactorial origin. Though 88% of the patients have clear grafts, a high incidence of associated posterior segment disease tends to nullify the visual result. Planned extracapsular cataract extraction and posterior chamber lens insertion (1979-1982) has reduced our incidence of PBK to 0.3% (1/300). These results are promising but premature.     

Indications for penetrating keratoplasty in a tertiary referral centre in Canada, 1996-2004

BACKGROUND: The leading indications for penetrating keratoplasty (PKP) have changed over recent years. This study examined the leading indications for PKP and their trends, comparing these with recently published data from other studies, including a report from our centre examining indications from 1986 through 1995. METHODS: A retrospective chart review was conducted of all patients who underwent PKP in a single practice at the University Health Network, Toronto Western Hospital, between July 1, 1996, and June 30, 2004. RESULTS: A total of 617 patients underwent 794 PKP operations during the 8-year study period. Sufficient documentation was available to include 777 surgeries from 600 patients in this study. Specific indications for PKP were reported and grouped into 16 categories. The leading indication categories for PKP were regraft (209 cases, 26.9%), pseudophakic bullous keratopathy (PBK) (193 cases, 24.8%), primary corneal endotheliopathies including Fuchs' endothelial dystrophy (101 cases, 13.0%), anterior keratoconus (93 cases, 12.0%), and viral or postviral causes (41 cases, 5.3%). Regraft, keratoconus, and Fuchs' endothelial dystrophy each displayed a nonsignificant decreasing trend from 1996 to 2004, and PBK, herpes simplex virus, and mechanical trauma each displayed a nonsignificant increasing trend (p > 0.05 for all). INTERPRETATION: Regraft was the leading indication for PKP at our centre, followed by PBK; these findings were in agreement with data reported in recent literature. The frequency of regraft had increased since a previous study from our centre (1986-1995), and the frequency of PBK had decreased.     

Propionibacterium acnes isolated from explanted intraocular lens in pseudophakic bullous keratopathy

Propionibacterium acnes is an anaerobic bacterium that has been reported to produce ocular infection or inflammation following surgery or penetrating trauma. It has been well documented as an etiologic agent associated with infections of prosthetic implants, including intraocular lenses (IOLs). P. acnes is part of the natural flora of the external eye and has biological properties that may promote, heighten, or prolong an inflammatory response. It not only resists in vitro degradation by reticuloendothelial cells, but also demonstrates adjuvant properties in vivo. In this study, we cultured the IOLs removed from patients undergoing routine penetrating keratoplasty for pseudophakic bullous keratopathy (PBK). Four of the 12 IOLs were culture positive for P. acnes as late as 36 months postimplantation. Although this does not describe a role for P. acnes in PBK, it does suggest that the organism can remain in the pseudophakic eye for an extended time.     

Indications for penetrating keratoplasty: 1980-1988

A retrospective analysis was undertaken of the clinical diagnoses of 1594 eyes that underwent penetrating keratoplasty performed in a private-referral corneal practice over a 9-year period, 1980-1988. The seven most common indications for surgery were keratoconus (24.0%), pseudophakic or aphakic bullous keratopathy (21.2%), corneal scarring (13.9%), Fuchs' endothelial dystrophy (12.5%), regraft (8.1%), and herpetic keratitis (5.3%). Keratoconus was the leading indication from 1980 to 1985. From 1985 to 1988, pseudophakic bullous keratopathy became the leading indication and correlates well with known complications associated with closed-loop anterior chamber lenses, which were widely used during the early 1980s. Less frequent indications for penetrating keratoplasty included the following: infectious (nonviral) keratitis (3.5%); acute or chronic ulcerative keratitis (2.7%); interstitial keratitis (1.8%); mechanical trauma (1.5%); other (non-Fuchs') corneal dystrophies (1.4%); congenital opacities (0.8%); and chemical burns (0.5%).     

Posterior chamber IOL implantation during keratoplasty for aphakic or pseudophakic corneal edema

Because of their many advantages, posterior chamber (PC) intraocular lenses (IOLs) were sutured to the posterior iris (in the absence of a lens capsule) in combination with penetrating keratoplasty for aphakic and pseudophakic corneal edema in 53 cases. Secondary PC IOL implantations were performed in aphakic corneal edema (nine cases), and IOLs were exchanged for PC IOLs in pseudophakic corneal edema (44 cases). Ninety-six percent of the grafts remained clear. Forty-three percent of the eyes had 20/40 or better visual acuity, 38% between 20/50 and 20/200, and 19% worse than 20/200, with an average follow-up time of 6.4 (range 3-13) months. The most common cause of poor vision was cystoid macular edema present preoperatively in 20 eyes and postoperatively in 22 eyes. Other causes of persistent visual impairment included macular degeneration (five cases), retinal detachment (two cases), preoperative glaucoma damage (one case), severe postoperative glaucoma damage (one case), endophthalmitis (one case), and graft rejection (one case). Our short-term results indicate that this procedure may be a viable alternative to the use of secondary anterior chamber IOL implantation during penetrating keratoplasty.     

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.