Outpatient penetrating keratoplasty

Elective penetrating keratoplasty has been performed on an outpatient basis on 37 patients since July 1987. The commonest indications have been herpetic keratitis, keratoconus, and pseudophakic or aphakic corneal oedema. Local anaesthesia, with little or no sedation, was used in most cases, and only three patients had a general anaesthetic. Accompanying procedures have included anterior vitrectomy, extracapsular cataract extraction with posterior chamber lens implantation and IOL exchange. The results demonstrate that outpatient keratoplasty is a safe, effective alternative to hospitalisation, and has a very high level of patient acceptance.     

Current concepts and techniques in corneal transplantation

The corneal endothelium is the most important single layer in corneal transplantation. In his Castroviejo Lecture, William Bourne, MD, summarizes his work on the corneal endothelium and its importance to corneal transplantation. Almost half the corneal transplants performed in the United States are done so because of malfunctioning, diseased, or absent endothelial cells. If just this layer could be transplanted, the long wait for better vision after keratoplasty (up to two years in some countries) can be eliminated, as well as the problems of epithelial and subepithelial graft rejection. The significant astigmatism after keratoplasty could also be reduced. Transplantation of the endothelium in deep lamellar keratoplasty is being done in limited fashion throughout the world and the first patients have now been done in the United States. In many countries where corneal tissue is difficult to obtain, keratoplasty is only performed on one eye, even though both eyes may need it. One article this year discusses binocular vision recovery in bilateral keratoplasty and the objective and subjective improvements after bilateral keratoplasty. Patients who are bilaterally blind from diseases such as Stevens-Johnson syndrome, and ocular pemphigoid have little hope of visual recovery from conventional corneal transplants. The use of a keratoprosthesis to bypass the totally abnormal conjunctival surface has helped many people in the past. The preoperative prognostic categories of patients who may benefit from keratoprosthesis has been carefully reviewed in a large number of keratoprosthesis patients and this information will help ophthalmologists decide who will benefit the most benefit from keratoprosthesis. This year, articles on corneal transplantation after conjunctival flaps, suture-related complications in keratoplasty, the implantation of an intraocular lens after penetrating keratoplasty, and long-term results of penetrating keratoplasty with glaucoma drainage tube implants are subjects that warrant in depth discussion and evaluation. Finally, eye bank considerations will be discussed concerning the long-term question of transmission of cancer through corneal transplantation.     

Long-term use of saturn II and softperm contact lenses for keratoplasty and keratoconus: a case report

A 48-year-old female has been successfully wearing, for over 8 years, the Saturn II/SoftPerm contact lenses on her right eye, which has had a penetrating keratoplasty, and on her left eye, which has keratoconus. Because of the tight fitting characteristics of the SoftPerm lens when used on keratoplasty and keratoconus patients, adverse effects might be expected with long-term use of the lens. None have occurred with this patient, except occasional diffuse edema with long hours of wear and neovascularization along the peripheral suture cicatrix lines on the right cornea that had the keratoplasty.     

Penetrating keratoplasty vs. epikeratoplasty for the surgical treatment of keratoconus

PURPOSE: Penetrating keratoplasty and epikeratoplasty have been utilized in the surgical treatment of keratoconus. Comparison of the relative efficacy of each procedure in achieving visual outcomes has not been achieved due to limited numbers of cases and follow-up in previous series. METHODS: All patients who underwent either penetrating keratoplasty or epikeratoplasty for keratoconus between January 1987 and December 1997, and for whom at least 24 months of postoperative follow-up data for visual acuity was documented in the medical record, were included in this retrospective, nonrandomized, sequential comparative trial. The sole criteria for outcome in each group, as well as for comparison of the two groups, was Snellen visual acuity measured at the time of each follow-up with the presenting optical aid. RESULTS: Inclusion criteria were met for 443 eyes treated with penetrating keratoplasty and 161 eyes treated with epikeratoplasty. Mean follow-up was 4.3 years for penetrating keratoplasty and 4.5 years for epikeratoplasty. In each group, approximately 50% of the patients chose rehabilitation with optical correction with either spectacles or contact lenses and 50% chose no optical correction. Final median logMAR visual acuity for all patients, irrespective of means of visual rehabilitation, was 0.30 (20/40) for penetrating keratoplasty and 0.40 (20/50) for epikeratoplasty (P < .00005). In 209 penetrating keratoplasty and 77 epikeratoplasty eyes with optical correction, the final median logMAR visual acuity was 0.18 (20/30) for penetrating keratoplasty and 0.40 (20/50) for epikeratoplasty (P < .00005). The final median logMAR visual acuity in 234 penetrating keratoplasty and 84 epikeratoplasty eyes without optical correction was 0.48 (20/60) in both groups (P-value was not statistically significant). CONCLUSIONS: Although penetrating keratoplasty was statistically superior to epikeratoplasty with respect to visual outcome, results with epikeratoplasty were adequate to recommend its use as a surgical alternative in cases when it is not desirable to perform penetrating keratoplasty.     

Experience in penetrating keratoplasty in children: graft survival, functional results and risk factors

Penetrating keratoplasty in children is related with a labor-consuming process of follow-up and care as well as with a high risk of graft rejection and a moderate vision improvement. Nonetheless, keratoplasty has been and still remains a surgery of choice due to a lack of an alternative procedure; its technique and results have been gradually promoted in practice. The authors analyzed 112 keratoplasties in childhood-age corneal opacifications of different types. The graft survival amounted to 71%, 61% and to around 55% after 1, 2 and 5 postoperative years, respectively. Neovascularization, glaucoma, repeated keratoplasty, an original vitreous pathology, an expanded surgical scope (reconstructions) etc. were attributed to risk factors. The visual acuity improved by more than 0.02 in 54% of cases; it remained unchanged or worsened in 22% of cases and it could not be assessed in 24% of cases. The best results were achieved in a group of patients with acquired corneal opacifications of the nontraumatic nature; the worst results were observed in congenital anomalies of the anterior eye segment. Finally, the success of penetrating keratoplasty in children was ensured through a careful selection of patients, an accurate surgical technique and through a fast treatment of postoperative complications.     

角膜移植术式的重大变化趋势

角膜移植手术是治疗多种角膜疾病的有效方法，有时是唯一方法。能否正确选择手术时机和手术方式，对于治疗效果至关重要。因手术技术的改进、对感染性角膜病较早采用板层角膜移植且疗效肯定、对穿透性角膜移植术后植片慢性失功等问题的发现、研究和认识，以及免疫排斥反应仍是角膜移植早期失败的主要原因，所以传统观念上穿透性角膜移植和板层角膜移植的适应证发生巨大变化，对传统的适应证提出了新的挑战。     

Descemet-stripping automated endothelial keratoplasty: a successful alternative to repeat penetrating keratoplasty

Background: Although Descemet‐stripping automated endothelial keratoplasty has replaced penetrating keratoplasty for primary treatment of endothelial disorders, many patients have already undergone penetrating keratoplasty. It is unclear when repeat penetrating keratoplasty is necessary or when endothelial keratoplasty may restore clarity to a failed graft. Design: Retrospective case series of patients undergoing Descemet‐stripping automated endothelial keratoplasty after penetrating keratoplasty by three surgeons at an academic tertiary care centre. Participants: Eight patients with Descemet‐stripping automated endothelial keratoplasty after penetrating keratoplasty from 2006 to 2009. Methods: Microkeratome‐prepared Descemet‐stripping automated endothelial keratoplasty donor tissue was used. In seven cases, the penetrating keratoplasty bed was neither stripped nor scraped, and in one, scraping only was performed. Main Outcome Measures: Preoperative and 6‐month postoperative best‐corrected visual acuities in logMAR (logarithm of the minimum angle of resolution). Results: The average pre‐Descemet‐stripping automated endothelial keratoplasty best‐corrected visual acuity was 1.375, and the average best‐corrected visual acuity 6 months postoperatively was logMAR 1.0, a 2.5‐fold improvement in the minimum angle of resolution (P = 0.22). Seven of the eight patients showed an improvement in best‐corrected visual acuity, and one patient had failure of Descemet‐stripping automated endothelial keratoplasty and required penetrating keratoplasty. Five had a postoperative event: one had a gap that resolved spontaneously, three required rebubblings (injections of air only without otherwise repositioning the graft), and one experienced graft failure. Conclusions: Descemet‐stripping automated endothelial keratoplasty can successfully rescue a prior penetrating keratoplasty, even with a fairly high detachment rate. Given these favourable visual outcomes, further study of this promising strategy is justified.     

快速生长型分枝杆菌性角膜炎的暴发与控制

目的 探讨角膜异物伤后快速生长型分枝杆菌性角膜炎（RGMK）暴发的原因与控制措施.方法 回顾性系列病例研究.调查2007年7月1日至8月5日南通一基层医院在角膜异物剔除术后暴发的11例（11眼）RGMK,了解患者的发病和初诊情况,以及当地医院、接诊医生和患者的工作场所,并采集标本做细菌培养.控制措施包括重视无菌操作,剔除角膜异物时摒弃戊二醛浸泡的角膜异物针,首选一次性针头,选用高压蒸汽法消毒替代戊二醛消毒液消毒等;治疗方法有局部和全身应用抗生素,5%碘酊烧灼清创病灶甚至角膜移植.结果 RGMK暴发感染的原因为异物本身带菌或使用的戊二醛难以杀灭快速生长型分枝杆菌,导致异物针带菌污染角膜造成感染.9例患者经局部和全身应用多种抗生素及5%碘酊烧灼清创病灶后治愈,2例以药物治疗无明显疗效,经角膜移植后治愈.结论 RGMK可在角膜异物剔除术后暴发流行,其对药物治疗反应慢,顽固性病例可经角膜移植而治愈.加强劳动防护,重视无菌操作,提高消毒灭菌质量,异物剔除术毕使用多种抗生素,术后密切随访观察等有利于预防和减少RGMK的发生.     

角膜移植的研究进展

角膜移植是用透明、健康的供体角膜组织替换混浊病变的角膜组织,使患者复明或控制角膜病变,达到增进视力或治疗某些角膜疾病的眼科治疗方法.传统角膜移植分为穿透性角膜移植和板层角膜移植.近10a,深板层角膜移植和内皮细胞移植手术逐渐崛起.而目前,人工角膜移植手术的发展为不适合传统穿透性角膜移植手术的患者提供一种新的选择.本文综述了目前角膜移植领域手术技术的适应证、术后并发症等.     

Conductive keratoplasty

PURPOSE OF REVIEW: Conductive keratoplasty is a noninvasive, in-office procedure for the correction of hyperopia, hyperopic astigmatism, and management of presbyopia. It serves as an alternative to laser-based refractive surgery with essentially no intraoperative or postoperative complications. RECENT FINDINGS: In the past decade, photorefractive keratectomy and laser in-situ keratomileusis have been the most popular refractive surgical procedures to correct myopia, hyperopia and astigmatism. Although relatively safe, flap-related complications often result in undesirable visual acuity. Since US Food and Drugs Administration approval in 2002, conductive keratoplasty has become a promising technique to correct low to moderate hyperopia and astigmatism. The procedure was first used by Mendez and colleagues in 1993. It is a nonlaser, no cutting procedure that delivers radio-frequency energy to corneal stroma in a circular fashion to steepen the cornea. Multiple studies have shown that conductive keratoplasty offers equal or superior efficacy, predictability, stability and safety than currently used refractive procedures to correct hyperopia or hyperopic astigmatism. In addition, monovision conductive keratoplasty has been shown to be successful for the management of presbyopia. SUMMARY: Conductive keratoplasty, an alternative to the laser-based procedure, is effective, predictable, and safe to correct low to moderate hyperopia, astigmatism, and manage presbyopia.     

Endothelial keratoplasty – a review

From its inception over a century ago, penetrating keratoplasty grew to become the most common and most successful form of solid tissue transplantation. Yet clinicians have long recognized the limitations of full‐thickness corneal transplants, including prolonged visual rehabilitation, unpredictable refractive changes, susceptibility to ocular surface complications and vulnerability to traumatic wound rupture. Selective replacement of diseased or damaged posterior corneal layers was conceptualized and implemented a half century ago. However, it has only been within the past decade that improved techniques and instrumentation have allowed endothelial keratoplasty (EK) to become the preferred treatment for patients with endothelial dysfunction. EK provides more rapid visual recovery, minimizes induced astigmatism and, most importantly, better maintains globe integrity than penetrating keratoplasty. Descemet stripping automated EK is currently the most widely used method. This article covers how EK techniques have evolved over time, considers who is or is not an appropriate candidate for EK, describes Descemet stripping automated EK methods and instrumentation, discusses EK postoperative complications and management and compares visual recovery, refractive outcomes and endothelial cell loss with that of standard penetrating keratoplasty.     

Tectonic sclerokeratoplasty and tectonic penetrating keratoplasty as treatment for perforated or predescemetal corneal ulcers.

PURPOSE: To report the clinical outcome of patients with perforated or predescemetal corneal ulcers treated by tectonic, centric or eccentric penetrating keratoplasty or by tectonic sclerokeratoplasty. DESIGN: Nonrandomized clinical trial. METHODS: The study included 60 patients (60 eyes) with perforated or predescemetal corneal ulcers who were consecutively operated on by the same surgeon. Fifty-two patients underwent tectonic penetrating centric or eccentric keratoplasty. Eight patients with paralimbal corneal ulcers underwent tectonic sclerokeratoplasty. A control group consisted of 76 patients (76 eyes) electively undergoing central penetrating keratoplasty for treatment of inactive central corneal scars. RESULTS: In the study group with perforated or predescemetal corneal ulcers, best-corrected postoperative visual acuity ranged from perception of light to 0.80 (median, 0.10), with 54 of 60 eyes (90%) attaining an improvement of best visual acuity. In 10 of 60 patients (16.7%), tectonic penetrating keratoplasty had to be re-performed because of a recurring corneal ulcer. Patients with sclerokeratoplasty and patients with eccentric keratoplasty did not differ in clinical outcome, despite larger trephine and corneal lesion size in the sclerokeratoplasty group. Among study patients compared with control patients, postoperative visual acuity was significantly lower (P =.01), postoperative refractive and keratometric astigmatism were significantly higher (P <.05), and immunologic graft reactions (P =.02) and suture loosening (P <.001) occurred significantly more often. CONCLUSIONS: Eyes with perforated corneal ulcers or predescemetal corneal ulcers can usually be saved by tectonic keratoplasty or sclerokeratoplasty, with a moderate to considerable amount of remaining useful vision. In case of doubt, one may prefer conservative treatment of corneal ulcers and to electively perform central keratoplasty when the ulcers have healed. For selected clinical situations, sclerokeratoplasty is an alternative to keratoplasty for surgical treatment of paralimbal corneal defects.     

飞秒激光辅助角膜移植手术在圆锥角膜治疗中的应用

飞秒激光是一种以脉冲形式运转的红外线激光,在圆锥角膜的手术治疗中得到了很好的应用,与传统手术方式相比,飞秒激光辅助的穿透性角膜移植术和飞秒激光辅助的深板层角膜移植术在圆锥角膜患者术后均取得了良好的临床效果和更高的安全性。本文就近几年飞秒激光在圆锥角膜手术治疗中的应用进展进行综述,并结合我们临床应用中的经验和体会进行阐述。     

Highly active antiviral and immunosuppressive combination therapy with acyclovir and mycophenolate mofetil following keratoplasty in patients with herpetic eye disease

BACKGROUND: Herpes simplex virus (HSV) infection is the most common cause of corneal blindness in developed countries. Penetrating keratoplasty is the only therapeutic option for visual rehabilitation in patients with severely scarred corneas. Recurrence of the underlying disease and allograft rejection (AR) are the common causes of graft failure. Systemic immuno-suppression with cyclosporin A is contraindicated due to the risk of HSV recurrence. The potent immunosuppressive properties of mycophenolate mofetil (MMF) have already been shown clinically. By reducing the intracellular guanosid-pool MMF inhibits the proliferation of lymphocytes. As these quanosin-nucleosides also act as competing substrates to acyclovir at the viral DNA-polymerase, a synergistic effect of MMF and acyclovir might be expected. The aim of this study was to evalute the efficacy and safety of a double-drug regimen with MMF and acyclovir in the prevention of acute allograft rejection and HSV recurrence following corneal transplantation. METHODS: Patients following penetrating keratoplasty due to herpetic eye disease have been treated with MMF 1 g twice dialy and acyclovir 5 x 200 mg/day for one year. Primary efficacy variables have been the number of acute AR and recurrence of herpetic disease per patient and time. The number of adverse events has been documented for safety analysis. RESULTS: Fifteen patients have been enrolled. The average follow up period was 9.1 (+/- 5.2) months. No graft opacifications have been seen. With two AR and no recurrence of herpetic disease the efficacy ofthis therapeutic regimen was supperior compared with historical control groups. CONCLUSION: In this first study on the efficacy and safety of a double drum regimen with acyclovir and MMF for the control of acute corneal AR and HSV-recurrenct following keratoplasty in patients with herpetic eye disease, the combination therapy has been shown to be a safe and highly efficient protocol for graft protection.     

Keratoplasty after mustard gas injury: clinical outcome and histology

PURPOSE: Ocular injury by mustard gas can lead to severe eye damage with a delayed course. We report the corneal histology and follow-up after keratoplasty in a patient with mustard gas injury. METHODS: The patient presented with recurrent painful corneal inflammation in both eyes not improving under local therapy. Visual acuity impaired to handmovements. A penetrating keratoplasty was performed on the left eye and afterwards an autorotation keratoplasty on the right eye with a later corneal graft. RESULTS: After the operation of the left eye the patient was immediately painfree and the visual acuity improved to 0,4. So far there have been no signs for transplant rejection or inflammation. Histology of the cornea revealed massive stromal necrosis, and signs of chronic inflammation. Despite denervation of the cornea after autorotation keratoplasty the right eye was still painful and became only painfree after corneal transplantation. CONCLUSION: There has been not much experience with corneal transplantation after mustard gas injury and there is a high risk for transplant rejection due to inflammation and vascularisation of the cornea. Successful and painfree healing with keratoplasty seems only possible after complete removal of the necrotic material.     

角膜移植治疗角膜重度热烧伤的临床研究

为探讨及评价早期角膜移植抢救角膜重度热烧伤的临床价值，用角膜移植术抢救有穿孔危险或已经穿孔的角膜重度热烧伤２０例。其中板层移植术１６例、穿透性角膜移植４例、对术后眼球保存、视力、角膜植片情况、并发症作了观察。结果，术后全部眼球得以挽救，７５％视力增进。结论，角膜重度热烧伤一旦角膜溶解变薄或穿孔，应尽快行板层或穿透性角膜移植     

Retrospective analysis of deep lamellar keratoplasties

BACKGROUND: Purpose of this retrospective study was to analyse the outcome of deep lamellar keratoplasty. PATIENTS AND METHODS: The records of 9 patients with deep lamellar keratoplasty were reviewed. Age, sex, systemic diseases, indication for surgery, pre- and postoperative visual acuity and findings, visual acuity and findings at last follow-up and complications were noted. RESULTS: Nine eyes of 9 patients have been operated with the "big bubble" technique described by Anwar. Indications for operation were keratoconus (4), keratoglobus (1), central corneal scar after keratitis (3) and after alkali burn (1). In 3 cases the intraoperative technique had to be changed to penetrating keratoplasty. The preoperative visual acuity was 0.2 to 0.3. All 9 patients showed a postoperative improvement of visual acuity: best corrected from 0.3 to 0.8. In one eye particles in the interface were found. At last follow-up all grafts were clear. There were no postoperative complications. CONCLUSIONS: The results demonstrate that deep lamellar keratoplasty is a technically difficult procedure, in 3 out of 9 patients the operation method failed. The postoperative course after deep lamellar keratoplasty did not show any severe complications. The patients who had to be changed to penetrating keratoplasty were not disadvantaged in respect of the final result (visual acuity and findings). The postoperative visual acuities after deep lamellar keratoplasty and after penetrating keratoplasty were comparable. Despite the small number of patients and the relatively short observation period, we noticed that after deep lamellar keratoplasty the sutures could tendentially be removed earlier and thus the duration of topic steroids therapy was shorter compared to penetrating keratoplasty.     

Successful visual rehabilitation after neonatal penetrating keratoplasty

BACKGROUND—Penetrating keratoplasty in infancy and childhood has traditionally met with limited visual success due to a combination of unique physiology and technical problems in this patient population. With the advances in microsurgical instrumentation, corneal preservation, and visual developmental physiology ophthalmologists are finding increasing indications for penetrating keratoplasty in the childhood population. The long term results of neonatal penetrating keratoplasty in two patients with unilateral congenital corneal opacification are reported.
METHODS—Penetrating keratoplasty was performed on one eye in each of two infants within the first 3 weeks of life. Amblyopia treatment and optical therapy have been continued since surgery.
RESULTS—After 6 years both grafts have remained clear. One patient developed the infantile esotropia syndrome. Visual development using Snellen optotypes is age normal for both transplanted eyes.
CONCLUSIONS—Penetrating keratoplasty when combined with optical correction and amblyopia therapy may restore and preserve vision in selected patients with congenital corneal opacification if performed in the neonatal period.

     

Penetrating keratoplasty and keratolimbal allograft transplantation for corneal perforations associated with the ectodermal dysplasia syndrome

PURPOSE: To report two patients with ectodermal dysplasia-associated keratopathy treated with keratolimbal allograft transplantation and penetrating keratoplasty.METHODS: Two patients with ectodermal dysplasia suffered multiple corneal perforations. In both patients, keratolimbal allograft transplantation was performed along with penetrating keratoplasty. Histopathology of the corneal buttons was obtained. RESULTS: Histopathologic examination showed chronic inflammation with thin, irregular epithelium, loss of stromal tissue, and thin or absent Bowman's membrane. Both patients had multiple contributing factors predisposing them to corneal perforations including an inherent ectodermal defect, trichiasis, poor tear film, and limbal stem cell deficiency. CONCLUSIONS: Patients with keratopathy and corneal perforations associated with the ectodermal dysplasia syndrome has a poor prognosis. Keratolimbal allograft transplantation may have a role in the treatment of this disease. Longer follow-up and additional case reports will determine whether this technique confers a better prognosis than keratoplasty alone.     

Outcome analysis of cataract surgery following therapeutic keratoplasty

PURPOSE: To assess the results of cataract surgery, in terms of visual outcome and effect on graft survival, in eyes that have previously undergone therapeutic penetrating keratoplasty for infective keratitis. METHODS: Case records of patients who had undergone cataract surgery alone (group A) or in combination with regrafting (group B) following initial therapeutic penetrating keratoplasty between January 2000 and December 2001 were reviewed retrospectively. Main outcome measures studied were visual acuity, astigmatism, and effect of the cataract surgery on graft survival. Results were compared with eyes undergoing cataract surgery after optical keratoplasty and between eyes in groups A and B. RESULTS: Frequency of cataract surgery after therapeutic keratoplasty was significantly greater than that following optical keratoplasty [68 (52%) versus 47 (21%); P<0.001]. Fifty-eight eyes of 58 patients undergoing cataract surgery after therapeutic penetrating keratoplasty were analyzed in detail. Mean follow-up period was 8.9 months (+/-7.6 months). Thirty eyes underwent cataract surgery alone (group A), and 28 eyes underwent cataract surgery with regrafting (group B). Eyes that had undergone therapeutic keratoplasty were significantly more likely to have opaque grafts requiring regrafting at the time of cataract surgery than eyes that had undergone optical keratoplasty [28 (48.3%) versus 5 (10.6%); P<0.001]. Incidence of graft failure after cataract surgery did not differ significantly in eyes that had undergone therapeutic or optical keratoplasty. Final visual acuity at last follow-up was 6/12 or better in 25 eyes (43%). There were no significant differences between eyes in groups A and B in terms of final visual acuity, astigmatism, or graft failure rates. CONCLUSIONS: Visual results of cataract surgery following therapeutic keratoplasty are comparable to those following optical keratoplasty. Combining a repeat keratoplasty for a failed graft with the cataract surgery does not significantly affect the final outcome.