Tectonic epikeratoplasty: a surgical procedure for corneal melting

BACKGROUND AND OBJECTIVE: Tectonic epikeratoplasty (TEK) is a method in which a corneal button, preserved in glycerin is used as a seal over corneal perforation. The graft is sutured to the recipient sclera, upon the sick melted cornea, with silk sutures, after 360 degree peritomy of the conjunctiva. The graft is left in place for a few weeks, and by that time the cornea is completely healed. We describe our experience in TEK as a method of treatment for selected cases of melted cornea or descemetocele. METHODS AND PATIENTS: We review 12 TEK operations done in our department over the period of 1992 to 1997, and describe the outcome in each case. RESULTS: The 12 TEK operations included 9 eyes of 9 patients. The patients, 7 males and 2 females, suffered from ocular surface disturbances including indifference to pain syndrome, Steven-Johnson syndrome, dry eye, relapsing herpetic keratitis, post-traumatic corneal thinning, and local anesthetic abuse. Six of the 9 eyes had leaking perforated corneal ulcer, and the remaining 3 had an imminent perforation caused by descemetocele or melting. All the grafts but one fell off the eyes between 10 and 21 days following surgery. In most of the cases the leakage ceased, and a scar sealing the perforation site was observed. One eye had gone through this procedure 3 times, and another eye had gone through it twice. In only 3 cases did the procedure fail to eliminate leakage, and another TEK or urgent penetrating keratoplasty (PKP) was done. CONCLUSIONS: TEK is an available method for saving the integrity of the globe when PKP is not possible. Although it increases corneal vascularity, PKP can be done later under optimal conditions.     

斑状角膜营养不良的临床特征及手术治疗

目的探讨斑状角膜营养不良患者的临床特征、诊断及手术治疗。设计回顾性病例系列。研究对象18例(36眼)斑状角膜营养不良患者。方法分析患者临床资料,包括病史、视力、裂隙灯显微镜检查以及手术治疗方法和术后随访结果。主要指标角膜病变及角膜移植片的裂隙灯显微镜图像。结果斑状角膜营养不良患者的临床表现有双眼视力进行性下降;裂隙灯显微镜检查发现双眼角膜基质雾状混浊,间以局灶性斑块或结节状灰白色混浊,斑块状混浊在中央部位于基质浅层而在周边则位于深层。在所有患者中行穿透性角膜移植术者14例(18眼),随访6至112个月,角膜植片均保持清亮。结论斑状角膜营养不良有其特征性临床表现,据此可明确诊断。对于中重度患者,穿透性角膜移植术是一种有效的治疗手段。(眼科,2006,15:169-172)     

Descemet stripping endothelial keratoplasty: effect of the surgical procedure on corneal optics

PURPOSE: To determine the changes in corneal optical performance after posterior lamellar corneal transplantation. DESIGN: Retrospective case series. METHODS: The anterior segment in four eyes of four patients who underwent Descemet stripping endothelial keratoplasty (DSEK) with cataract extraction and intraocular lens (IOL) implantation were imaged with the Visante anterior segment optical coherence tomography [OCT] (Carl Zeiss Meditec, Dublin, California, USA). The curvature of the posterior surface of the donor graft was compared with that of the host cornea, and corneal thickness was measured. RESULTS: All eyes had a hyperopic refractive error after surgery. The posterior corneal curvature after surgery was more than that before surgery. Average preoperative keratometry was 43.4 diopters (D), and after surgery, it was 42.8 D using keratometry. However, when the postsurgical corneal power was calculated using the Gaussian optics method, the average value was 40.8 D. CONCLUSIONS: The addition of a donor corneal graft to the posterior surface of decompensated corneas may lessen the effective optical power of the cornea and may have implications for IOL power calculations in these eyes.     

Use of split-thickness dermal graft in the surgical treatment of corneal and scleral defects

We used split-thickness dermal grafts for the surgical treatment of corneal and scleral perforations in two patients and obtained excellent results. Patient 1 had severe lye burns and bilateral corneal perforations and Patient 2 had scleromalacia perforans. The dermal graft self-epithelializes and, thus, does not need to be covered by conjunctiva; is supple, without the bulkiness of other materials, particularly cartilage and periosteum; is hearty and flourishes on avascular surfaces such as cornea and sclera; has good tensile strength; and is autogenous.     

Replacing the endothelium without corneal surface incisions or sutures: the first United States clinical series using the deep lamellar endothelial keratoplasty procedure

PURPOSE: To report the 6- and 12-month results of the first United States clinical series of deep lamellar endothelial keratoplasty (DLEK) in the treatment of endothelial dysfunction. DESIGN: Prospective, noncomparative, interventional case series. PARTICIPANTS: Eight eyes of eight patients with corneal edema from Fuchs' dystrophy and pseudophakia. METHODS: A 9.0-mm limbal, scleral, partial-depth incision provided access for a deep lamellar corneal pocket dissection. A 7.5- to 8.0-mm posterior lamellar disc of recipient tissue was then excised and replaced through the pocket with a same size donor disc containing healthy endothelium. A temporary air bubble in the anterior chamber was used for donor tissue adherence, and no surface corneal incisions or sutures were necessary. MAIN OUTCOME MEASURES: Preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), manifest refraction astigmatism, TMS-1 topography, ultrasonic pachymetry, Orbscan topography, and endothelial cell density were evaluated. Intraoperative and postoperative complications are reported. RESULTS: At 6 and 12 months after surgery, all eight corneas were clear and the grafts were healed in good position. At 6 months, the BSCVA varied between 20/30 and 20/70, the average change in astigmatism from before surgery was +1.13 diopters (D; +/-1.50 D), the average change in corneal power was -0.4 D (+/-1.7 D), the average pachymetry was 648 micro m (+/-134 micro m), and the average endothelial cell count was 2290 cells/mm(2) (+/-372 cells/mm(2)). At 12 months, three of the four eyes reaching this time gate were 20/40 or better, with a change in astigmatism from before surgery of only +0.81 D (+/- 0.55 D), a corneal power change of -1.3 D (+/- 0.4 D), and an endothelial density of 2409 cells/mm(2) (+/- 154 cells/mm(2)). One of the original nine eyes entered into this study required conversion to standard penetrating keratoplasty as a result of a microperforation during recipient pocket dissection and has experienced no ill effects. CONCLUSIONS: The DLEK procedure, with its absence of corneal surface incisions and sutures, is a safe procedure that preserves the normal corneal topography, minimizes astigmatism and corneal power changes, and provides a healthy donor endothelial cell count and function. If interface optical clarity can be maintained, then this technique offers considerable advantages over penetrating keratoplasty in the treatment of endothelial dysfunction.     

Endothelial replacement without surface corneal incisions or sutures: topography of the deep lamellar endothelial keratoplasty procedure

PURPOSE: To evaluate the immediate postoperative corneal topography after the deep lamellar endothelial keratoplasty procedure. METHODS: Eight eye bank eyes underwent deep lamellar endothelial keratoplasty through a 9.0-mm limbal incision replacing the central 7.0 mm of posterior stroma and endothelium through the lamellar pocket wound. Orbscan topography was performed before and after surgery, and simulated keratometry readings and central corneal diopter power were recorded. The change in astigmatism and corneal power from preoperative to postoperative readings was then determined. RESULTS: The net change in corneal astigmatism averaged 0.4+/-0.5 diopters (range, -0.1 to 1.1 diopters). The net change in corneal power averaged -0.2+/-0.4 diopters of flattening (range, -0.9 to +0.2 diopters). Neither the astigmatism nor the corneal power levels after this surgery were significantly different from the preoperative topography (p = 0.22 and 0.27, respectively). CONCLUSIONS: The deep lamellar endothelial keratoplasty procedure, with its absence of corneal surface incisions or sutures, has no significant effect on immediate postoperative corneal topography. The potential advantages of this procedure over penetrating keratoplasty in the treatment of endothelial dysfunction are considerable.     

Interaction between surgical procedure for repairing retinal detachment and clinical risk factors for proliferative vitreoretinopathy

PURPOSE: To asses risk factors of proliferative vitreoretinopathy (PVR) and a model for predicting it. METHODS: Observational, case-control. 335 patients with non-complicated retinal detachment (RD) were included: 134 developed PVR (Cases); 201 patients did not (Controls). Risk factors for PVR were identified by multivariate analysis. Influence of variables was assayed according to the surgical approach. By logistic regression analysis a model to predict the risk of developing PVR and odds ratio (OR) values for each clinical factor were estimated. RESULTS: Risk was higher in patients > 70 years and with intraocular pressure lower than 14 (OR: 3.84; CI 95%: 2.04-7.30) and in retinal breaks larger than "1 clock hour" (OR: 2.54; CI: 1.28-5.05), extended retinal detachments (OR: 4.01; CI: 1.98-8.10) and reinterventions (OR: 1.55; CI: 1.14-9.22). Scleral surgery also was a risk factor (OR: 3.89; CI: 2.12-7.14) and aphakia/pseudophakia when scleral surgery is performed (OR: 3.33; CI: 1.54-7.22). A model to predict PVR was proposed with these results. CONCLUSIONS: Surgical approach modifies risk factors of PVR, and should be taken into account to improve the models for predicting it.     

A case of corneal keloid: clinical, surgical, pathological, and ultrastructural characteristics.

A 69-year-old patient developed a localised, whitish, elevated, corneal lesion with a smooth and glistening surface following trauma, without evidence of corneal perforation. Twelve months later, the lesion showed evidence of slow growth. An excisional biopsy was then performed. Histopathologically, the lesion was covered by non-keratinised squamous epithelium and was comprised of randomly oriented collagen fibres containing active fibroblasts. Blood vessels were noted deep in the lesion. Ultrastructurally, the cell population was formed by fibroblasts and myofibroblasts, similar to keloids of the skin. The clinical, pathological, and ultrastructural features of the corneal lesion are compatible with a corneal keloid.     

Evaluation of efficacy and safety of botulinum toxin type A injection in patients requiring temporary tarsorrhaphy to improve corneal epithelial defects

AIM: To evaluate the efficacy and safety of botulinum toxin type A (Dysport, (Ipsen Biopharm Ltd, Wrexham, UK)) injection in patients requiring temporary tarsorrhaphy to improve corneal epithelial defects. METHODS: Thirty patients were enrolled into the prospective study between March 2007 and September 2009. Doses of 15 and 30U of Dysport were injected into the levator palpebrae superioris muscle through the eyelid. The patients were followed daily until completion of ptosis and then 1-2 weekly until complete resolution of levator function and improvement of corneal condition. RESULTS: Ptosis took 2.64±1.85 days to be completed (range 1-9 days) and lasted for 12±2.19 weeks. For patients with seventh nerve palsy, 30U Dysport was appropriate to produce sufficient ptosis whereas in other patients 15U of toxin was sufficient. In 83.3% of patients ptosis was sufficient for complete recovery of corneal epithelium and 16.7% required a second procedure (Amniotic membrane transplantation, conjunctival flap). There was a direct correlation between age and duration of ptosis. In patients with seventh nerve palsy, the amount of resultant ptosis was significantly lower than that of other patients. The only adverse effects of injection were superior rectus underaction (33.3%) and diplopia (16.7%) which resolved in all patients without any intervention. CONCLUSION: Dysport injection is a safe and effective substitute for surgical tasorrhaphy with fewer complications.     

The era of lamellar keratoplasty, evolving surgical techniques in corneal transplantation: the University of Toronto experience

ObjectiveTo analyze the changing trends in corneal transplantation techniques and the way selective lamellar transplantation has influenced our practice.DesignRetrospective survey of all corneal transplants performed by a single practice at Toronto Western Hospital.ParticipantsAll corneal transplants performed by our office since 2002, the year we performed our first lamellar transplant.MethodsWe retrospectively reviewed all keratoplasty procedures performed in our office between January 2002 and December 2010. Procedures were classified as penetrating keratoplasty (PKP); deep lamellar endothelial keratoplasty (DLEK); Descemet's stripping automated endothelial keratoplasty (DSAEK); or deep anterior lamellar keratoplasty (DALK).ResultsA total of 1104 procedures were performed in this period (average, 122.6 per year). Of these, 654 were PKPs (59.3%); 107 DLEKs (9.7%); 219 DSAEKs (19.8%); and 124 DALKs (11.2%). The number of PKPs performed decreased by 61.8% over this 9-year survey. For the last 4 years of the study, the proportions of PKP, DSAEK, and DALK procedures performed were 41%, 40%, and 19%, respectively.ConclusionsThis 9-year audit showed that in less than a decade since its introduction at our institution, selective lamellar transplantation has become the procedure of choice for corneal keratoplasty, accounting for 59% of all transplants performed over the past 4 years.     

Therapeutic keratoplasty for corneal perforation: clinical results and complications

PURPOSE: To report the clinical results, postoperative progress, and complications after therapeutic keratoplasty for corneal perforation. METHODS: Twenty consecutive eyes (20 patients) that underwent therapeutic keratoplasty between December 2003 and May 2006 were included. The eyes were evaluated retrospectively for the cause of the corneal perforation, the type of surgical technique and intraoperative complications, anatomic cure rates, graft clarity, visual prognosis, and postoperative complications. RESULTS: The causes of corneal perforation were herpetic keratitis (n = 5), bacterial ulcer (n = 1), fungal ulcer (n = 1), neurotrophic ulcer (n = 3), rheumatoid arthritis (n = 2), Mooren ulcer (n = 2), Terrien marginal corneal degeneration (n = 1), keratoconus (n = 1), and Wegener granulomatosis (n = 1). In 3 cases, the etiology was unknown. Six cases had a previous history of corneal transplantation. Anatomic cures were obtained in 16 (80%) of 20 eyes after the first transplantation procedure. Visual acuity (VA) equal to or better than the preoperative level was achieved in 17 (85%) of 20 eyes. The graft transparency rate was 67% in 15 eyes that underwent central penetrating keratoplasty with fresh donor tissue. Major postoperative complications included cataract (n = 6), glaucoma (n = 4), and recurrent disease (n = 3). CONCLUSIONS: Keratoplasty is valuable for maintaining the ocular integrity and VA. In cases with severe preoperative inflammation of the anterior segment, it is difficult to achieve transparency after the first graft.     

甘油冷冻保存角膜深板层移植治疗真菌性角膜溃疡的临床研究

目的探讨甘油冷冻保存的供体角膜行深板层角膜移植术治疗浅、中层真菌性角膜溃疡的手术适应证及临床效果。方法57例（57眼）经综合抗真菌措施治疗无效的浅、中层真菌性角膜溃疡施行深板层角膜移植术,随访8～24月,观察术后复发率、视力恢复、植片透明及并发症发生情况。结果57例中,52例治愈,成功率91.23%;5例复发,复发率8.77%。矫正视力0.1～0.2者20眼,0.3～0.5者24眼,〉0.5者13眼。17例出现新生血管;13例发生排斥反应,均得到有效控制。植片全部透明。结论使用甘油冷冻保存的角膜供体行深板层角膜移植术既能及时去除病变组织,达到治疗目的,又有一定的增视效果,对药物治疗无效的浅、中层真菌性角膜溃疡是有效的手术方式。     

Efficacy and safety of chlorambucil in intractable noninfectious uveitis: the Massachusetts Eye and Ear Infirmary experience.

PURPOSE: To report our experience with the use of chlorambucil for otherwise treatment-resistant uveitis and to assess its safety and efficacy. DESIGN: Noncomparative interventional case series. PARTICIPANTS: Twenty-eight patients with intractable noninfectious uveitis. METHODS: We reviewed the records of 28 patients (56 eyes) with chronic noninfectious uveitis who were treated with chlorambucil from 1987 to 2000. Diagnoses included Adamantiades-Beh?et's disease (ABD) (7 patients), juvenile rheumatoid arthritis (JRA)-associated uveitis (10 patients), pars planitis (2 patients), sympathetic ophthalmia (1 patient), idiopathic uveitis (6 patients), Crohn's disease (1 patient), and HLA-B27-associated uveitis (1 patient). All patients were refractory to other immunomodulatory therapy and systemic steroids. The median duration of treatment with chlorambucil was 12 months (range, 4-50 months), whereas the median daily dosage was 8 mg (range, 4-22 mg). Patients were followed for a median follow-up period of 46 months (range, 4-166 months) after chlorambucil treatment was begun and continued to be followed for relapse after cessation of therapy. MAIN OUTCOME MEASURES: Visual outcome, response to treatment, treatment-related side effects, drug dosage, previous and final treatment, discontinuation of systemic corticosteroids. RESULTS: Chlorambucil was discontinued in seven patients because of side effects: two females had temporary amenorrhea develop, two patients had unacceptable gastrointestinal intolerance, one patient had infection, and 2 patients had progressive leukopenia. Nineteen patients (68%) showed positive clinical response to the treatment, four (14%) initially responded then relapsed after discontinuation of the drug, three patients with ABD had improvement of ocular disease but worsening of systemic symptoms, and two had persistent inflammation. Visual acuity was improved in 24 eyes (43%), stable in 22 (39%), and worsened in 10 eyes (18%). Systemic prednisone was successfully discontinued in 19 of the 28 patients (68%), and 14 patients were free of inflammation at the end of follow-up without any systemic medication. CONCLUSIONS: Chlorambucil can be a safe and effective alternative for preserving vision in patients with otherwise treatment resistant uveitis.     

Silicone oil in the surgical treatment of retinal detachment--indications and clinical experience]

Silicone oil is being used with increased frequency for retinal tamponade during vitreous surgery for complicated retinal detachments. Though it is now possible to reattach most detached retinas, the visual outcome of the silicone oil procedure is often disappointing. This is due to the well known complications of silicone oil (i.e. cataract, glaucoma, corneal opacification), and the necessity to remove the silicone oil in a second surgical procedure with a certain risk of redetachment. Possible toxicity to retina and optic nerve has not yet get been completely evaluated. An alternative method is the use of expanding gases for internal retinal tamponade. Expanding gases are not as effective as silicone oil in advanced stages of proliferative vitreoretinopathy (PVR), but are afflicted with much less complications. We reviewed the charts of our patients, operated on for retinal detachment, to analyse the anatomical and functional results with silicone oil versus gas tamponade. Regarding the last 421 consecutive surgical procedures for retinal detachment (368 eyes), silicone oil has been used in 5%, expanding gases in 14%. The silicone oil procedure was restricted to the most advanced cases of PVR. The anatomic success rate with silicone was 72%, with gas tamponade 87%. Visual acuity of 0.05 and better achieved 19% of the eyes treated with silicone oil versus 61% of the eyes with gas tamponade. These results confirm the findings of other investigators: despite of the high anatomic success rate with silicone oil, the functional results are poor. Because many complicated cases of retinal detachment can also be treated successfully with gas tamponade, silicone oil should remain the last step in retinal detachment surgery.     

Local anaesthesia for vitreoretinal surgery: an audit of patient and surgical experience

PURPOSE: Local anaesthesia for vitreoretinal surgery is little used as these procedures are deemed to be too long and uncomfortable for patients to tolerate. In this unit anterior intraconal local anaesthesia is used for most routine surgery. We undertook an audit to ensure that surgical standards and patient acceptability were not compromised. METHODS: A prospective observational audit was performed. Audit data included: Grade of anaesthetist and surgeon; details of anaesthetic and operation; compliance of patient; operating conditions and pain scores. Anaesthesia was provided with a combined peribulbar and intraconal anaesthetic, using bicarbonate buffered lignocaine and bupivacaine 50:50 mixture. RESULTS: 135 (76%) had local anaesthesia alone, 13 (7%) had local anaesthesia with sedation and 29 (16%) had general anaesthesia. 96.4% of patients were compliant and 98.8% of operating conditions were good or excellent. The mean perioperative pain score was 0.1 (range of 0-1), 97% said they would choose local anaesthesia again. CONCLUSIONS: LA for vitreoretinal surgery is a useful and flexible method of anaesthesia, which has been shown to have excellent patient tolerance.     

Viscocanalostomy and deep sclerectomy for the surgical treatment of glaucoma: a longterm follow-up

PURPOSE: To study the outcome of viscocanalostomy (VC) and deep sclerectomy (DS) for the surgical management of medically uncontrolled glaucoma. PATIENTS AND METHODS: A non-randomized, prospective study of all consecutive non-penetrating glaucoma filtering procedures was carried out in two centres. In the first centre, one surgeon (MSW) performed VC in 105 eyes (27 VC and 78 phaco VC). In the second centre, one surgeon (PKW) performed DS in 87 eyes (52 DS and 35 phaco DS). RESULTS: The mean follow-up was 36 months (range 9-60 months). At final follow-up the complete success rate (intraocular pressure < or = 21 Hg without medication) was 92.6% for VC eyes, 96% for phaco VC eyes, 77% for DS eyes and 94% for phaco DS eyes. Kaplan-Meier survival analysis for complete success showed no significant difference between DS and VC nor between phaco VC and phaco DS (p > 0.05). By 36 months postoperatively, mean IOP was 16.8 mmHg (SD 3) in VC eyes, 16.6 mmHg (SD 3.1) in phaco VC eyes, 16.7 mmHg (SD 5.7) in DS eyes and 15 mmHg (SD 3.2) in phaco DS eyes. Postoperative Nd:YAG laser goniopuncture was necessary in 10 eyes in the DS group. Large or cystic drainage blebs occurred only in the DS eyes. CONCLUSIONS: Viscocanalostomy and DS are effective and safe methods of achieving sustained IOP reduction in glaucomatous eyes and both techniques can be successfully combined with cataract extraction.