Tacrolimus immunosuppression in high-risk corneal grafts

BACKGROUND: Unlike the immune privilege enjoyed by low-risk corneal grafts, high-risk corneal grafts experience rejection rates comparable to liver and kidney transplants. Systemic immunosuppression reduces the risk of rejection in high-risk corneal grafts. METHODS: Systemic tacrolimus, a specific T cell inhibitor, was used at a mean daily dose of 2.5 mg to immunosuppress 43 patients undergoing high-risk corneal transplantation. Immunosuppression was continued for a period of 18-24 months after the high-risk corneal graft. RESULTS: During a mean follow-up period of 33.7 months, clarity of the graft was maintained in 65% of patients. Eight patients experienced rejection episodes while on tacrolimus, and this led to graft failure in five patients. CONCLUSION: Tacrolimus is relatively safe and effective in reducing rejection and prolonging graft survival in patients with high-risk keratoplasty compared with other series where similar immunosuppression was not used.     

Long-term use of topical tacrolimus (FK506) in high-risk penetrating keratoplasty

PURPOSE: To evaluate the long-term efficacy and side effects of off-label topical tacrolimus 0.03% ointment (Protopic; Fujisawa Health, Deerfield, IL) as a sole second-line immunosuppressive agent in the management of high-risk corneal grafts. METHODS: Four consecutive patients underwent high-risk penetrating keratoplasty (4 grafts) with a prior diagnosis of corneal scar secondary to herpetic keratitis, keratoconus, acanthamoeba keratitis, and Fuchs endothelial dystrophy, respectively. All 4 patients developed steroid-induced glaucoma and failed traditional immunosuppressant therapy. Patients were started on topical tacrolimus ointment 0.03%, twice daily, which was tapered to the lowest possible therapeutic dose that maintained its antirejection efficacy. Patients were monitored for adverse treatment effects. The mean follow-up was 33 months (range, 26-48 months), and the mean treatment duration was 22.6 months (range, 13-32 months). RESULTS: All 4 high-risk corneal transplant patients experienced episodes of acute rejection that was successfully reversed with topical tacrolimus treatment. During tacrolimus treatment, there were no further episodes of graft rejection and no incidents of herpes simplex virus infection or reactivation, with the longest follow-up being 4 years. Two patients have been successfully tapered off tacrolimus, and 2 patients are currently on once-daily dosing. No adverse effects were observed. CONCLUSIONS: Topical tacrolimus 0.03% ointment seems to be a promising second-line immunosuppressant in management of high-risk grafts.     

Bedeutung der Cyclosporin-A-Absorption für eine effektive immunmodulatorische Therapie nach Hochrisikokeratoplastik

AIM: Cyclosporin A (CsA) is applied as an immune modulator in transplantation medicine, including high-risk keratoplasty. We examined the C(0) and C(2)-CsA serum levels after high-risk keratoplasty. The rate of so-called low absorbers was determined, and the importance of low absorption for the survival and rejection freedom of corneal grafts was examined. METHODS: Follow-up of 89 high-risk cornea grafts in the patient group (n=32) ranged from 1 to 72 months postoperatively. The evaluation included data about serum levels of CsA C(0) (24 h after oral CsA application) and C(2) (2 h after oral CsA application) and clinical follow-ups. Using statistical methods, CsA C(0) and C(2) levels and clinical data were examined. Low absorbers did not reach the target C(2) levels by CsA dose adjustment. OUTCOMES: High intraindividual and interindividual variance of CsA C(0) and C(2) values was observed in the examined group of patients. A rate of up to 34.4% (n=11) represented the low absorbers. There was no significance of the low-absorption factor for clear graft survival, rejection freedom, or the rate of side effects observed. An acute endothelial rejection was observed in 23% of grafts and caused 37% of graft failures. In the patients without rheumatic corneal ulcers (n=27), 89% of the corneal grafts remained clear after 12 months, and 52% remained clear after 36 months. CONCLUSIONS: In our study, with a low number of patients and multiple cofactors, the influence of low-absorption CsA on the clear corneal graft survival and rejection rates could not be proved statistically. Due to the specific immune status of the cornea, the influence of low absorption may be lower than in organs such as the kidney and liver. In our study, the C(2) serum level of CsA after high-risk keratoplasty did not provide any helpful information about the prognosis of the corneal grafts or CsA treatment monitoring.     

The use of systemic cyclosporin a in human corneal transplantation: a preliminary report

Four patients (six eyes) underwent successful corneal transplantations while receiving systemic cyclosporin. The six eyes had marked corneal vascularization preoperatively and in four, previous grafts had rejected. These eyes were therefore at high risk with respect to the likelihood of rejection and subsequent graft failure. All six grafts have remained clear (mean follow up twelve months) and only one minor rejection episode has occurred: this was easily reversed. The patients were monitored by repeated serum creatinine and trough serum cyclosporin levels. No significant side effects were encountered.     

Immunologic rejection of the central graft after limbal allograft transplantation combined with penetrating keratoplasty

PURPOSE: To study the incidence and prognosis of immunologic rejection of the central graft after limbal allograft transplantation (keratolimbal allograft transplantation [KLAT]) combined with penetrating keratoplasty (PKP). METHODS: Endothelial rejection in central penetrating graft after simultaneous KLAT and PKP using the same donor cornea was retrospectively studied. Incidence, reversibility, prognosis, and changes in limbal grafts were examined. RESULTS: Forty-five eyes underwent simultaneous PKP and KLAT. Endothelial rejection of the central graft was found in 16 eyes (35.6%). At last examination, 10 grafts (62.5%) restored clarity after immunosuppressive therapy. During rejection episodes, four eyes showed engorgement of vessels in limbal grafts, which existed before the episodes. Only one eye developed neovascularization with mild edema of the limbal grafts; however, no other limbal grafts showed abnormalities on biomicroscopy. No epithelial changes were noted, and 14 grafts (87.5%) were covered by corneal epithelium after the rejection. CONCLUSION: Approximately one third of eyes had endothelial rejection in the central graft after simultaneous KLAT and PKP. Abnormalities suggestive of rejection in the limbal grafts were seldom observed in these eyes, suggesting that immunologic response was different in central and limbal grafts.     

Changes observed in keratolimbal allograft

OBJECTIVE: To study the incidence and clinical characteristics of presumed immunologic reactions in limbal grafts after keratolimbal allograft(KLAL). METHODS: A total of 121 KLALs performed in consecutive 85 eyes of 78 patients with total limbal stem-cell deficiency were analyzed retrospectively. Mean follow-up period was 46.6 months. Three types of limbal graft changes classified as epithelial defects, acute edema, and vascular engorgement were analyzed as probable signs of immunologic rejection. RESULTS: One or more changes in limbal grafts were observed after 16 KLALs (13.1%). All but 1 eye used systemic and local immunosuppression using corticosteroid and cyclosporine A, and most of the changes developed within 3 months postoperatively. All but 2 eyes developed epithelial breakdown in the central cornea, and 12 corneas underwent conjunctivalization. The rate of corneal epithelialization in eyes with limbal graft changes was significantly worse than those without the changes (P < 0.0001). Histologic examination in eyes with the limbal graft changes revealed high incidence of lymphocyte infiltration. CONCLUSIONS: Presumed limbal graft rejection occurred in approximately 13% of cases after KLAL. Suppression of the immune reaction remains a key to success in KLAL.     

Opinions on risk factors and management of corneal graft rejection in the United kingdom

PURPOSE: To determine the opinions regarding risk factors and practice preferences for corneal graft rejection by members of the Bowman Club (UK) and to compare them with those of members of the Castroviejo Society (USA). METHODS: A questionnaire was sent in 1999 to members of the Bowman Club (UK), who were responsible for two thirds of all corneal grafts undertaken annually. The survey included 8 questions identical to those given to members of the Castroviejo Society (USA) in a survey carried out in 1989. RESULTS: Thirty-six out of 40 surgeons replied. Factors considered by respondents to be high risk for corneal graft rejection were previous corneal graft rejection in the operated eye (97%), significant corneal vessels (97%), and previous herpetic eye disease (94%). The preferred routine preoperative treatment in "high-risk" patients included no treatment (47%), topical corticosteroids (33%), and oral prednisolone (22%). In postoperative "high-risk" patients, 100% of surgeons used topical and 42% used oral corticosteroids. Immune suppression agents were used by 44% of respondents, the majority (92%) using cyclosporine A. In previous herpes simplex patients, 47% of surgeons used oral and 14% used topical antivirals preoperatively, whereas 75% used oral and 47% used topical postoperatively. CONCLUSION: This study documents the perceived risk factors and management of corneal graft rejection by corneal surgeons in the UK. It showed wide variation in practice preferences, allowing individual surgeons a comparison with peer practice. It highlights the need for greater use of postoperative antiviral prophylaxis in the presence of previous herpetic corneal pathology.     

Prevention and treatment of corneal graft rejection: current practice patterns (2004)

PURPOSE: This study was designed to analyze current practice patterns in the prevention and treatment of corneal graft rejection and to compare these patterns with previously reported practices. METHODS: In January 2004, a survey addressing the routine postoperative management of corneal transplants and the treatment of various manifestations of corneal graft rejection was sent to members of The Cornea Society. RESULTS: Of the 396 surveys, 111 (28%) were returned and analyzed. All respondents used topical corticosteroids for routine postoperative management and treatment of endothelial graft rejection. Prednisolone, in brand or generic form, was used by 37 to 90% for routine management in various clinical scenarios and 81 to 91% for various manifestations of graft rejection at all time points; however, after 6 months, 12 to 26% used loteprednol etabonate for routine management. For routine management of high-risk grafts, 48% used topical cyclosporine in addition to prednisolone. Compared with previous surveys, the use of oral steroids significantly decreased for the routine management of high-risk corneal transplants, and the use of subconjunctival steroids decreased for the management of graft rejection. CONCLUSIONS: Topical prednisolone remains the mainstay for the prevention and treatment of corneal graft rejection; however, the role of newer agents, loteprednol etabonate and topical cyclosporine, is expanding.     

Long-term results of corneal graft survival in infants and children with peters anomaly

OBJECTIVE: To determine the long-term results of corneal graft survival after penetrating keratoplasty for Peters anomaly and to identify risk factors for graft failure. DESIGN: Noncontrolled interventional case series: a single-center retrospective review of a consecutive surgical series. PARTICIPANTS: The records of all children 12 years of age or younger who underwent penetrating keratoplasty for Peters anomaly between January 1971 and December 1992 were reviewed. All study eyes had completed a minimum of 3 years of follow-up from the date of first keratoplasty and had undergone most of their corneal surgery at Emory University. INTERVENTION: Characteristics of the recipient, the eye, the donor, and the surgical procedure were analyzed for their influence on survival of the first graft. Survival probabilities were estimated using the Kaplan-Meier method. Multivariate regression analysis was performed to estimate relative risks and adjusted survival probabilities. MAIN OUTCOME MEASURE: Graft clarity. RESULTS: One hundred forty-four penetrating keratoplasties were performed in 72 eyes of 47 patients. The median age at first keratoplasty was 4.4 months. The median follow-up was 11.1 years. Fifty-four percent of eyes received one graft, 18% received two grafts, and 28% received three or more grafts. The overall probability of maintaining a clear first graft was 56% at 6 months, 49% at 12 months, 44% at 3 years, and 35% at 10 years. The probability of second or subsequent grafts surviving for 3 years was less than 10%. Thirty-nine percent of eyes had a clear graft at the time of review; 36% of eyes had a clear first graft. Multivariate analysis identified disease severity, donor cornea size, coexisting central nervous system abnormalities, and quadrants of anterior synechiae as the strongest risk factors for graft failure. Supplemental multivariate analysis, restricted to observable preoperative variables, identified stromal vessels, total limbal opacification, and preoperative glaucoma as independent preoperative predictors of graft failure. Allograft rejection was the most frequently identified cause of graft failure. Major complications after keratoplasty were phthisis, retinal detachment, cataract, and glaucoma. CONCLUSIONS: The overall long-term probability of maintaining a clear graft after initial penetrating keratoplasty for Peters anomaly is 35% +/- 0.06%, with subsequent grafts rarely surviving. Eyes with severe disease, larger donor corneas, coexisting central nervous system abnormalities, and anterior synechiae have significantly poorer outcomes than eyes without these factors. These data should be carefully considered before recommending corneal transplantation for Peters anomaly, particularly after previous graft failure.     

Corneal allograft rejection: risk factors, diagnosis, prevention, and treatment

Recent advances in corneal graft technology, including donor tissue retrieval, storage and surgical techniques, have greatly improved the clinical outcome of corneal grafts. Despite these advances, immune mediated corneal graft rejection remains the single most important cause of corneal graft failure. Several host factors have been identified as conferring a "high risk" status to the host. These include: more than two quadrant vascularisation, with associated lymphatics, which augment the afferent and efferent arc of the immune response; herpes simplex keratitis; uveitis; silicone oil keratopathy; previous failed (rejected) grafts; "hot eyes"; young recipient age; and multiple surgical procedures at the time of grafting. Large grafts, by virtue of being closer to the host limbus, with its complement of vessels and antigen-presenting Langerhans cells, also are more susceptible to rejection. The diagnosis of graft rejection is entirely clinical and in its early stages the clinical signs could be subtle. Graft rejection is largely mediated by the major histocompatibility antigens, minor antigens and perhaps blood group ABO antigens and some cornea-specific antigens. Just as rejection is mediated by active immune mediated events, the lack of rejection (tolerance) is also sustained by active immune regulatory mechanisms. The anterior chamber associated immune deviation (ACAID) and probably, conjunctiva associated lymphoid tissue (CALT) induced mucosal tolerance, besides others, play an important role. Although graft rejection can lead to graft failure, most rejections can be readily controlled if appropriate management is commenced at the proper time. Topical steroids are the mainstay of graft rejection management. In the high-risk situations however, systemic steroids, and other immunosuppressive drugs such as cyclosporin and tacrolimus (FK506) are of proven benefit, both for treatment and prevention of rejection.     

Cyclosporin A eyedrops in the prevention of high-risk corneal graft rejection. II. Postoperative clinical results

Twenty-four patients (25 eyes) presenting a high corneal rejection risk have been treated by an association of topical cyclosporine A (2% in castor oil) and Dexamethasone eyedrops 1% 48 h preoperatively, the posology was slowly degressive postoperatively. The mean follow-up is of 12 months. Results are 19 clear grafts among which 4 had a reversible reject reaction, 3 unreversible rejections with a totally cloudy graft (12%), 3 corneal graft oedema of nonimmunologic nature allowing a counting fingers vision. A control group of 25 patients with the same high risks of rejection treated only by topical corticosteroids followed up for the same mean time showed an obvious higher rate of failure (65%).     

CTLA4-Ig抑制兔角膜移植排斥反应的作用

目的:建立兔角膜移植高危及非高危模型,通过阻断CD28,探讨CTLA4-Ig对高危角膜移植排斥反应的影响。方法:实验分为新生血管化模型组及非新生血管化组,每组随机分成:空白对照组(空白保存液)、实验组(浸入含有CTLA4-Ig10mg/L保存液4℃孵育18h),每组10只兔。观察术后受体植片角膜混浊情况和植片病理改变,原位杂交方法检测角膜植片TNF mRNA的表达情况,比较植片生存时间。结果:非新生血管化角膜移植组:对照组和实验各组的植片排斥时间或平均植片存活时间上无统计学意义,超过半数植片(16/30,53%)存活时间超过100d。新生血管化角膜移植组:实验组生存时间较长69±34d,对照组26±4d,原位杂交检测移植术后4wk或排斥反应发生时对照组角膜植片上皮下基质层浸润细胞有明显的TNF mRNA的表达,实验组未见TNF mRNA表达。结论:在兔角膜移植排斥反应中应用CTLA4-Ig阻断CD28,可以明显抑制兔高危角膜移植排斥反应,提高移植的存活率。     

角膜缘干细胞移植治疗翼状胬肉的临床观察

目的:观察角膜缘干细胞移植治疗翼状胬肉的临床疗效。方法:对40例45眼翼状胬肉患者行角膜缘干细胞移植术。观察术后角膜上皮修复,角膜缘新生血管及翼状胬肉复发情况。结果:术后随访5～48mo,42眼植片透明光滑,无异常胬肉样组织增生,3眼复发。复发率7%,治愈率93%。结论:角膜缘干细胞治疗翼状胬肉可有效防止翼状胬肉复发,具有复发率低的优点,是目前治疗翼状胬肉的一种安全有效的方法。     

Systemic cyclosporin A in high failure risk,repeated corneal transplantation

AIM: To evaluate the efficacy of oral cyclosporin A in the prevention and treatment of immune graft rejection in heavily vascularised, repeated keratoplasties with high risk for failure. METHODS: 21 consecutive patients with 28 repeated corneal transplants and four quadrant vascularised recipient bed were treated with oral cyclosporin A for an average period of 12 months (range 1-41 months) and followed for an average period of 26.6 months (range 6-106 months). The average cyclosporin A blood level was 325 ng/ml (range 180-421 ng/ml). Within this group of 21 patients, another 12 regrafts were not treated with cyclosporin A and served as a control group. RESULTS: Nine of the 28 regrafts (32%) treated with cyclosporin A remained clear. The Kaplan-Meier curve showed a constant decline in survival of the treated grafts, although the survival proportion during the first year of treatment was statistically higher for the treated group compared with the untreated group. Once immune regraft rejection occurred, the regraft failed despite treatment with cyclosporin A and extensive topical and systemic corticosteroids. Nine regrafts (32%) had immune graft rejection and all ultimately failed compared with five in the untreated regrafts (42%, p = NS). Ten other regrafts (36%) in the treatment group failed due to causes other than immune regraft rejection. CONCLUSIONS: Systemic cyclosporin A has a limited beneficial effect in preventing immune graft rejection in repeated corneal transplants in a highly vascularised corneal bed. When immune graft rejection occurs in such regrafts, the prognosis is poor despite aggressive medical treatment. Causes other than immune regraft rejection may also result in poor visual outcome in patients with clear regrafts.     

Mitomycin-C in combined or two-stage procedure trabeculectomy followed by penetrating keratoplasty.

PURPOSE: To evaluate the efficacy and safety of application of mitomycin-C (MMC) in combined and separate trabeculectomy and penetrating keratoplasty for the treatment of coexisting corneal disease and glaucoma. METHODS: A retrospective evaluation of 11 eyes of 10 patients was conducted. A combined trabeculectomy with MMC and penetrating keratoplasty procedure was performed in eight eyes (group 1), and keratoplasty was performed after a previous trabeculectomy with MMC in three eyes (group 2). RESULTS: In group 1, seven of the eight eyes had controlled intraocular pressure (IOP) and clear corneal graft at the end of the follow-up period (range, 5-60 months; mean duration, 16.7 months). In group 2, all three eyes had controlled IOP at the end of the follow-up period (range, 4-30 months; mean duration, 14 months); two of these patients had clear corneal grafts, and graft failure occurred in the remaining patient. Complications included transient flat anterior chamber and corneal epithelial defects, each of which occurred in a single eye in group 1, and progressive cataract, which occurred in a single eye in group 2. CONCLUSION: Mitomycin-C was found to be safe and efficient in the present series, controlling IOP in 10 of 11 eyes (91%) with coexisting corneal disease and glaucoma. The transplanted corneas remained clear in 9 of 11 eyes (82%). Complications related to MMC included a reversible epithelial defect that occurred in one eye.     

Limbal allografting from related live donors for corneal surface reconstruction

OBJECTIVE: To report the results of limbal allograft transplantation, from human leukocyte antigen (HLA)-matched and -unmatched related live donors, in patients with ocular surface disease due to chemical burns and Stevens-Johnson syndrome. DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: Eight patients (nine eyes) with severe chemical burns (n = 7 eyes) and Stevens-Johnson syndrome (n = 2 eyes). INTERVENTION: Recipient eyes were treated with excision of cicatricial tissues. Transplantation of superior and inferior limbal grafts was performed from related live HLA-matched (n = 7) and -unmatched donors (n = 2). Systemic cyclosporine was not used in any of the recipients. MAIN OUTCOME MEASURES: Reconstruction of corneal surface epithelium, restoration of avascularity, increase in ocular comfort, and improvement in visual acuity. RESULTS: With a mean observation period of 17.2 months, phenotypically corneal epithelium, decreased vascularization of the corneal surface, and improved ocular comfort were seen in seven (77.8%) eyes. In all seven eyes, gradual recurrence of peripheral corneal vascularization occurred during the follow-up period. Features of graft rejection developed in three (42.9%) of these seven eyes. In two eyes, limbal transplantation from HLA-unmatched donors failed to reconstitute the corneal surface. Limbal allograft transplantation resulted in visual acuity of 20/400 or greater in only two (22.2%) eyes at last follow-up. Corneal grafts performed 7 and 16 months after successful limbal transplantation in two eyes developed recurrent epithelial breakdown and superficial corneal scarring. None of the donor eyes in this study had any complication. CONCLUSION: Transplantation of limbal tissue from related live donors successfully reconstructs the corneal surface in HLA-matched recipients. Recurrence of vascularization on long-term follow-up probably results from inadequate stem cell transfer, immune-mediated stem cell damage, or both. Limbal allografting is best performed by transplanting the entire limbus from a cadaveric donor eye with systemic immunosuppression of the recipient, even if the donor is HLA-compatible.     

Cataract extraction following penetrating keratoplasty

OBJECTIVE: To assess the safety of cataract extraction following penetrating keratoplasty for corneal graft survival and to evaluate visual and refractive outcomes in corneal graft patients undergoing cataract extraction. METHODS: Retrospective chart review of 29 eyes of 24 patients with corneal grafts who underwent cataract extraction from January 1, 1993 to December 31, 2002, followed on the Cornea Service at Wills Eye Hospital. RESULTS: The mean time from penetrating keratoplasty to cataract extraction was 8.4 years (range 2 months to 36 years). Following cataract extraction, the corneal grafts remained clear in all but 1 eye (3%), during an average follow-up time of 44.5 months (range 3-118 months). All of the remaining patients benefited from improved visual acuity, with 15 of 28 patients having a postoperative best-corrected visual acuity of 20/30 or better. Patients also benefited from decreased absolute spherical refractive error, with a preoperative mean value of 6.6 +/- 3.4 D compared with 2.4 +/- 1.6 D postoperatively, while cylindrical refractive error remained relatively stable at 3.2 +/- 2.9 D preoperatively and 2.8 +/- 2.4 postoperatively. The patient who developed graft failure had 3 episodes of preoperative endothelial rejection and a clear corneal graft at the time of cataract surgery. CONCLUSIONS: Cataract surgery following penetrating keratoplasty is a safe and effective procedure, with a low but definite risk of corneal graft failure. In patients with clear grafts and visually significant cataracts, cataract extraction alone is preferred over repeat penetrating keratoplasty and cataract extraction.     

Outcome of Corneal transplantation rejection

PURPOSE: To identify predictive factors for reversibility of corneal graft rejection. METHODS: The study design was a prospective cohort study. Among 440 consecutive penetrating keratoplasties performed at our institution, 79 grafts from 79 patients who developed signs of transplant rejection were included. Donor, recipient, surgical, and rejection variables were studied, at both univariate and multivariate levels. RESULTS: The rate of reversibility was 51% (40/79). The average postoperative time of rejection was 10.5 +/- 9.3 months, and the average time of visual acuity recovery in patients with reversible rejection was 2.4 +/- 2.3 months. In logistic regression, only two variables significantly influenced the rate of reversibility. The preoperative diagnosis (p = 0.04) influenced the rate of rejection reversibility; patients with bullous keratopathy or regraft were more likely to experience irreversible rejection than patients with keratoconus or Fuchs' dystrophy. The average graft thickness at the time of rejection diagnosis was 774 +/- 129 microm in patients with irreversible rejection and 681 +/- 118 microm in patients with reversible rejection (p = 0.001). CONCLUSION: Rejection was reversible in half of the cases. Rejection was more likely to be irreversible in patients with marked increase in graft thickness and in patients transplanted for bullous keratopathy or graft failure. Donor variables did not influence rejection reversibility.     

Long-term outcomes of penetrating keratoplasty in chronic and delayed mustard gas keratitis

PURPOSE: To report the long-term outcomes of penetrating keratoplasty (PKP) in war victims with chronic and delayed mustard gas keratitis. METHODS: This noncomparative interventional case series includes patients with advanced chronic or delayed mustard gas keratitis who had undergone PKP from 1989 to 2006. Best-corrected visual acuity (BCVA), graft clarity, episodes of graft rejection, duration of steroid use, and complications were evaluated. Histopathologic features of excised corneal buttons were also evaluated. RESULTS: Overall, 22 eyes of 19 patients underwent PKP. Mean age at the time of surgery was 41 +/- 4.6 years (range, 36-54 years), and mean follow-up duration was 40.9 +/- 48 months (range, 4-204 months). The graft remained clear in 17 (77.3%) eyes and failed in 5 (22.7%) eyes. Overall, 13 (59.1%) eyes experienced episodes of endothelial rejection, and 5 (22.7%) eyes had subepithelial immune rejection, 4 of which had simultaneous endothelial rejection. Fifteen (68.2%) eyes received topical steroids for >6 months. Fourteen (63.6%) eyes developed cataracts, leading to cataract extraction in 7 eyes. One eye developed steroid-induced glaucoma after multiple episodes of endothelial graft rejections. Mean preoperative BCVA was 1.92 +/- 0.63 logMAR, which improved to 1.04 +/- 0.65 logMAR (20/200) overall and 0.8 +/- 0.3 logMAR (20/120) in eyes with clear grafts (P < 0.001). Main histopathologic features of excised corneal buttons included corneal thinning and ulceration, loss of keratocytes, acute and chronic inflammation, stromal vascularization, and degenerative sequelae of long-standing inflammation. CONCLUSIONS: PKP in chronic or delayed-onset mustard gas keratitis should be considered as a high-risk graft; however, with appropriate management, graft clarity and visual outcomes may be favorable.     

Fine needle diathermy occlusion of corneal vessels

PURPOSE: To develop a novel technique, fine needle diathermy (FND), for the occlusion of corneal vessels and to evaluate its safety and efficacy in a series of patients. METHODS: Fourteen patients were treated with FND to occlude corneal vessels. Patients were categorized into four groups: group 1 (n = 4), high risk patients with stromal vascularization before keratoplasty; group 2 (n = 2), patients with progressive lipid keratopathy; group 3 (n = 4), post keratoplasty patients with active rejection episodes associated with vessels; and group 4 (n = 4), patients with disciform vascularized scars with recurrent inflammation. The success of the treatment in terms of vessel occlusion and the clinical outcome were monitored. RESULTS: All patients in group 1 had successful corneal transplantation, and the grafts remained clear without graft rejection. Patients in group 2 with lipid keratopathy had 100% obliteration of vessels with stabilization of corneal scar. All four patients in group 3 had complete regression of vessels with reversal of graft rejection. Patients with vascularized disciform scar had resolution of the inflammation without recurrence. Average follow-up was 10.3 months (minimum, 6 months; maximum, 24 months). No serious complications were observed with FND. CONCLUSIONS: FND is a useful and inexpensive technique that can serve as an adjunct or alternative to laser occlusion for the treatment of established corneal vessels. It is fairly safe and effective, although complications such as intrastromal bleeding and crystalline deposits can occur and at times it may have to be repeated once or twice to achieve the desired result.