Protective effect of LASIK flap in penetrating keratoplasty following blunt trauma

Penetrating keratoplasty (PKP) often results in large and unpredictable refractive errors following suture removal in the postoperative period. Laser in situ keratomileusis (LASIK) is an effective means of correcting these errors. However, LASIK following PKP is believed to further weaken an already weak graft-host junction and may predispose such eyes to traumatic dehiscence of the graft-host junction. We describe a case in which the LASIK surgery following PKP seemed to benefit the patient by preventing complete dehiscence of the graft-host junction.     

Small, overlapping tectonic keratoplasty involving graft-host junction of penetrating keratoplasty

PURPOSE: To report the indications for and postoperative course of small tectonic keratoplasties overlapping (and involving) the graft-host junction of preexisting penetrating keratoplasties. METHODS: A retrospective study of 15 consecutive eyes (15 patients) with small tectonic keratoplasties overlapping the graft-host junction of preexisting penetrating keratoplasties. RESULTS: After tectonic keratoplasty, follow-up times ranged from 5 months to 20 years (mean, 69 months). Clinical indications included sterile corneal ulceration (seven cases), bacterial keratitis (six cases), and fungal keratitis (two cases). In the six cases with bacterial keratitis, five were suture abscesses, with four resulting in wound dehiscence. Ten tectonic grafts were lamellar keratoplasties, and five were penetrating keratoplasties. Postoperative best-corrected visual acuities were unchanged from preoperative levels in every patient. After tectonic grafting, the mean +/- SD change in keratometric astigmatism in the parent penetrating keratoplasty was 1.75 +/- 1.50 diopters. The astigmatism increased in 10 cases, decreased in three, and remained unchanged in two. There was no case of recurrent ulceration or wound dehiscence in or around the tectonic grafts. The surgery did not result in new glaucoma or worsening of preexisting glaucoma. CONCLUSIONS: In the treatment of infectious or ulcerative foci at or near the graft-host junction of penetrating keratoplasties, a small extirpative, tectonic graft over the diseased junction appears to be a safe and effective alternative to either repeating the original penetrating keratoplasty or performing an oversize transplant.     

Candida albicans interface infection after deep anterior lamellar keratoplasty

PURPOSE: To report a case of interface infection by Candida albicans after deep anterior lamellar keratoplasty (DALK). METHODS: A 30-year-old man with keratoconus underwent DALK. Four weeks after surgery, the patient developed multiple infiltrates in the graft-host interface with absence of intraocular infection. Donor rim cultures grew C. albicans. Penetrating keratoplasty (PK) was performed because of worsening of the infection despite topical, local, and systemic antifungal therapy. RESULTS: Cultures carried out on the excised donor cornea confirmed donor-to-host transmission of C. albicans. An aqueous tap taken before PK was negative. Six months after PK, the corneal graft was clear with no recurrence of infection. CONCLUSIONS: After DALK, in cases of donor graft microbial contamination, infection may develop at the graft-host interface. This may delay or prevent direct intraocular penetration of microorganisms, reducing the risk of development of endophthalmitis. PK may be needed to eradicate the infection in cases where conservative treatment fails.     

Wound dehiscence after penetrating keratoplasty: clinical characteristics of 51 cases treated at Bascom Palmer Eye Institute

PURPOSE: To describe the causes, clinical characteristics, and treatment of wound dehiscence in patients after penetrating keratoplasty (PK). METHODS: A retrospective chart review was completed, evaluating patients seen at Bascom Palmer Eye Institute between 1989 and 2001. RESULTS: All dehiscence occurred at the graft-host junction with an average of 5 hours of dehiscence, but no site preference was identified. Dehiscence occurred because of trauma (53%), suture-related complications (27%), infectious keratitis (8%), and spontaneous wound separation (12%). Twelve patients had either intraocular lens dislocation or expulsion; 42 patients underwent primary repair; 7 patients underwent primary PK; and 1 patient underwent primary evisceration. Surgical details were unavailable for 1 patient. Final visual acuity ranged from 20/20 to no light perception. Acuity was unavailable for 2 patients. Visual acuity was 20/200 or better in 23 patients (47%) and less than 20/200 in 26 patients (53%). Two patients (4%) had no light perception. The visual acuity of 13 patients (27%) was 20/40 or better at their last clinic visit. Comparison of predehiscence and postdehiscence visual acuity showed that 23 eyes (54%) had comparable vision after dehiscence, 11 eyes (25%) had improved vision, and 9 eyes (21%) had worsening of vision. CONCLUSIONS: These observations show that graft dehiscence can occur for a variety of reasons after PK, including trauma, infectious keratitis, suture failure, or spontaneous wound separation. The graft-host interface remains vulnerable after corneal transplant and is a potential area for wound dehiscence even many years after keratoplasty. Nevertheless, comparable or even improved vision is possible after wound dehiscence.     

Spontaneous wound dehiscence after removal of single continuous penetrating keratoplasty suture: conservative management

PURPOSE: To describe a case of spontaneous wound dehiscence (WD) following removal of single continuous penetrating keratoplasty (PKP) suture, who was treated conservatively with a bandage contact lens. METHODS: A 36 year-old man who had penetrating keratoplasty for keratoconus 15 months earlier and removal of the single continues suture the previous week underwent ocular examination. He was treated with topical dexamethasone 0.3%, chloramphenicol 0.5% and cyclopentolate 1% 3 times a day and had a bandage contact lens (BCL) inserted. RESULTS: On presentation, he was complaining of reduced vision, tearing and pain following an attack of rhinitis-induced sneezing. His visual acuity (VA) in the affected eye was counting fingers, the anterior chamber was formed, the intraocular pressure (IOP) was low and there was a 2-clock-hour WD with a positive Seidel test but no iris incarceration. Two months later, his corrected VA was 6/5, his IOP was normal and the graft-host junction was good with no uplift. CONCLUSIONS: A 2-clock-hour WD after single continuous PKP suture removal may be conservatively treated with a BCL.     

Traumatic wound dehiscence after penetrating keratoplasty: clinical features and outcome in 21 cases.

PURPOSE: To describe the characteristics, causes, treatment, and outcome, particularly the fate of the intraocular implant and visual acuity, of traumatic wound dehiscence occurring in patients who had penetrating keratoplasty (PK). METHODS: Between 1989 and 1997, 21 corneal transplant patients sustained traumatic wound dehiscence and were treated at our hospital. Graft dehiscence was managed with primary wound closure in all patients, except in some who required some combination of anterior vitrectomy, intraocular lens removal and reimplantation, and corneal regrafting. RESULTS: The incidence of traumatic wound dehiscence among patients on whom we performed PK over a period of 9 years was 2.53%. This complication occurred, on average, 3.4 years (2 months to 13 years) after PK. Most patients (76%) were men, and the average age at dehiscence was 59 years (range, 15-82 years). All corneal ruptures occurred at the graft-host junction, which had neither particular site preference nor quadrant specificity. Of the 16 eyes that were pseudophakic, nine (56.3%) had either loss of implants or dislocation of intraocular lens so severe that lens removal was imperative. In the end, only five (23.8%) of the 21 grafts retained clarity. Of the remaining 16 eyes, seven were regrafted, of which five (71.4%) grafts remained clear. Of the nine grafts that became opaque, six eyes (28.6%) atrophied. At the last follow-up, only six eyes (28.6%) had visual acuity of 20/200 or better, and six eyes had no perception of light. Final visual acuity was found to correlate inversely with the severity and extent of wound separation. CONCLUSION: Traumatic wound dehiscence is not rare after PK. The elderly corneal transplant patient may be more prone to such an injury. Corneal rupture at the graft-host junction in all of our cases means the persistence of wound weakness after PK. Although graft survival and visual outcome are generally poor after the injury, the restoration of a satisfactory visual result is possible after regrafting, insofar as the involved eye is free of intractable glaucoma or posterior segment damage.     

Traumatic wound dehiscence following penetrating keratoplasty

BACKGROUND AND PURPOSE: Blunt ocular trauma to a corneal transplanted eye represents a higher risk for wound rupture at the donor-recipient interface. We have evaluated the causes, clinical characteristics, treatment and outcome, particularly the graft's clarity, in patients with traumatic wound dehiscence after penetrating keratoplasty. METHODS: Between March 1996 and April 2006, over a period of 10 years, 4 patients who had previously undergone successful penetrating keratoplasty and subsequently sustained traumatic wound dehiscence were treated at our department. All eyes underwent primary wound closure with interrupted 10-0 nylon sutures. RESULTS: Over the 10-year period, the incidence of traumatic wound dehiscence in which penetrating keratoplasty was performed was 2.35 % (4 of 170 patients). The ages of our patients at the time of injury were 6, 76, 78 and 39 years. The interval between penetrating keratoplasty and trauma varied from 12 through 16 and 17 to 30 months. All corneal dehiscences occurred at the graft-host junction. All dehiscences were at the temporal-superior quadrant (4 of 4 eyes) and at superior-nasal and temporal quadrants in 3 of 4 eyes. Two eyes that were pseudophakic had lost their implants and required anterior vitrectomy. In one of these patients (a 76-year-old women) delayed-onset expulsive choroidal haemorrhage occurred at the end of surgical repair. Visual outcome was correlated with the force of trauma, previous eye conditions and complications during surgery. All of the resutured grafts retained clarity. CONCLUSION: Traumatic wound dehiscence is a serious and not uncommon complication following penetrating keratoplasty. Despite severe trauma, graft transparency was achieved in all cases and there was no need for regrafting.     

Candida interface keratitis following deep anterior lamellar keratoplasty

The purpose is to report a case of Candida interface infection after deep anterior lamellar keratoplasty (DALK). A 23-year-old female patient underwent DALK surgery in the left eye for keratoconus. Four weeks after the surgery, she presented with asymptomatic white-cream colored deposits at the graft-host interface. Epithelial ingrowth was our first possible diagnosis because there were no symptoms or signs of inflammation. However, progression of the lesion under steroid treatment and the appearance of inflammation signs after tapering the steroid treatment raised suspicion of fungal keratitis. Anterior segment optical coherence tomography (OCT), ultrasound biomicroscopy, confocal microscopy and microbiologic examinations of the cornea were performed to evaluate the lesion. Anterior segment OCT and ultrasound biomicroscopy confirmed the lesion to be at the interface. The confocal scan disclosed hyper-reflective deposits and surrounding inflammatory cells but there were no hyphae-like structures. While taking a specimen from the lesion, the Descemet's membrane ruptured so a penetrating keratoplasty was performed. The microbiologic examination revealed Candida infection. Candida interface keratitis is a rare infection seen after DALK. The asymptomatic clinical picture and the similarity to epithelial ingrowth may postpone the diagnosis and consequently the treatment. Therefore, in cases of interface deposits seen after lamellar surgery, one should consider Candida interface keratitis.     

Clinical outcomes after deep anterior lamellar keratoplasty using the big-bubble technique in patients with keratoconus

PURPOSE: To report clinical outcomes of deep anterior lamellar keratoplasty (DALK) using the big-bubble technique in patients with keratoconus. DESIGN: Prospective noncomparative interventional study. METHODS: Setting: Single hospital. Patients: Eighty-one unselected consecutive patients with moderate to advanced keratoconus intolerant to contact lenses and with poor spectacle-corrected visual acuity. Intervention: DALK big-bubble technique. Main Outcome Measures: Intraoperative and postoperative complications, postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refraction, corneal topography, and endothelial cell density. RESULTS: Seventy-eight procedures (96%) were completed as DALK. Big-bubble was achieved in 50 cases (64%); 28 (36%) required manual intrastromal dissection. Intraoperative microperforations occurred in 11 cases (13%). Baseline mean uncorrected visual acuity was 20/500 and 20/60 two years after surgery. Average preoperative BSCVA, was 20/100 and 20/30 at the end of follow-up. Final BSCVA was better in patients in whom big-bubble with exposure of the Descemet membrane was achieved (P < .05). Average keratometry and SD (standard deviation) refraction changed from 62.1 +/- 6.7 diopters and -10.76 +/- 5 diopters to 47.51 +/- 4.73 diopters and -1.81 +/- 3.2 diopters, respectively after surgery. Mean preoperative endothelial cell density was 2202.29 +/- 392.35 cells/mm(2) and 2034 +/- 438.39 cells/mm(2) two years after surgery. Two patients developed stromal rejection. CONCLUSIONS: The DALK big-bubble technique is a valuable treatment in patients with keratoconus. Visual outcome is comparable to standard penetrating keratoplasty (PK) when formation of big-bubble with exposure of the Descemet membrane (DM) was achieved. Clinically important graft-host interface developed in some cases after manual intrastromal dissection. Stromal rejection is a rare complication.     

实验性角膜移植术后内皮创伤愈合的形态学定量分析

采用扫描电镜与计算机图象分析技术联合应用的方法，对２０只家兔进行了穿透性角膜移植术后内皮创伤愈合的形态学定量分析，结果展示了术后不同时间伤口部位角膜内皮细胞面积、周长、密度、形状系数、最大长径、变异系数的数值，并对内皮愈合机制进行了进一步探讨。     

暴露后弹力层的前部深板层角膜移植手术进展

前部深板层角膜移植术（deep anterior lamellar keratoplasty,DALK）是一种新的角膜移植技术,该技术将去除后弹力层和内皮层的供体角膜移植到去除全部基质的植床上,以期望获得与穿透角膜移植术相同的光学效果,同时减少术中和术后并发症.DALK对手术技术要求高,关键步骤是暴露后弹力层.暴露后弹力层的方法经历了直接分离法、基质无菌空气辅助分离法、水分离法、黏弹剂法、大泡技术等,这些技术在不断改进且日趋成熟.DALK的优点是保留了眼球结构和免疫的相对完整性,可减少术后内皮型免疫排斥反应、角膜植片慢性功能失代偿以及角膜植片因外伤哆开的风险.本文就DALK的适应证、手术技术和并发症等进行综述,为其技术改进和广泛临床应用提供思路.     

Bilateral deep anterior lamellar keratoplasty for the management of bilateral post-LASIK mycobacterial keratitis

A 25-year-old Vietnamese man who had bilateral simultaneous laser in situ keratomileusis (LASIK) for moderate myopia developed bilateral Mycobacterium abscessus keratitis that was treated with intensive medical therapy, flap removal, superficial keratectomy, and, following disease progression, therapeutic deep anterior lamellar keratoplasty (DALK). To our knowledge, this is the first reported case of bilateral post-LASIK mycobacterial keratitis successfully treated with DALK.     

Deep anterior lamellar keratoplasty for the management of iatrogenic keratectasia occurring after hexagonal keratotomy

Iatrogenic keratectasia has been reported subsequent to refractive surgery or trauma. Hexagonal keratotomy (HK) is a surgical incisional technique to correct hyperopia. A number of complications have been reported following this procedure, including irregular astigmatism, wound healing abnormalities and corneal ectasia. When visual acuity is poor because of ectasia or irregular astigmatism and contact lens fitting is not possible, penetrating or lamellar keratoplasty can be performed. Since incisions in refractive keratotomy are set at 90-95% depth of cornea, intraoperative microperforations are known to occur and lamellar keratoplasty may become difficult. We describe deep anterior lamellar keratoplasty (DALK) used to successfully manage keratectasia after HK. Pre DALK vision was 20/400 and post DALK vision was 20/30 two months after surgery. This report aims to show improved visual outcome in corneal ectasia secondary to HK. DALK can be a procedure of choice with proper case selection.     

Comparison of Clinical Outcomes of Same-size Grafting between Deep Anterior Lamellar Keratoplasty and Penetrating Keratoplasty for Keratoconus

Purpose

To compare the clinical outcomes between deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PKP) with same-size grafts in patients with keratoconus.

Methods

Medical records of 16 eyes from 15 patients treated from June 2005 through April 2011 were retrospectively reviewed. Patients with contact lens intolerance or who were poor candidates for contact lens fitting due to advanced cone underwent keratoplasty. The transplantations consisted of 11 DALK and 5 PKP with same-size grafting for keratoconus. Best-corrected visual acuity (BCVA), refractive error, corneal topographic profiling, and clinical course were compared between DALK and PKP groups.

Results

The follow-up period was 30 ± 17 months in the DALK group and 45 ± 20 months in the PKP group (p = 0.145). At final follow-up, the DALK and PKP groups achieved a BCVA (logarithm of the minimum angle of resolution) of 0.34 and 0.52, respectively (p = 0.980). Postoperative refractive error and mean simulated keratometric index showed myopic astigmatism in both groups without any statistical difference. Corneal irregularity index measured at 5 mm in the DALK group was less than that of the PKP group at 1-year follow-up (p = 0.021); however, at final follow-up, there was no longer a statistically significant difference. Endothelial cell counts were lower in the PKP group than in the DALK group at final follow-up (p = 0.021).

Conclusions

The optical outcomes of DALK with same-size grafts for keratoconus are comparable to those of PKP. Endothelial cell counts are more stable in DALK compared to PKP.     

Hydrophilic contact lenses for wound stabilization in keratoplasty

Hydrophilic contact lenses may be used in selected cases in which penetrating keratoplasty is complicated by partial wound dehiscence and anterior slippage of the donor tissue. We report five cases and describe a technique in which, rather than resuturing, a soft contact lens is used as a corneal stent to realign the graft-host interface. This technique allows for non-surgical correction of a potentially serious complication, with preservation of good vision during the treatment period. In the present series, no serious complications were encountered, and all wounds were adequately reapposed. Successful application of this technique requires appropriate patient selection and careful monitoring during the course of treatment.     

Combined special capsular tension ring and toric IOL implantation for management of post-DALK high regular astigmatism with subluxated traumatic cataract

We report a case of 18-year-old male who has undergone phacoemulsification with implantation of toric IOL (AcrySof IQ SN6AT9) after fixation of lens capsule with Cionni''s capsular tension ring (CTR) for subluxated traumatic cataract with high astigmatism after deep anterior lamellar keratoplasty (DALK). He underwent right eye DALK for advanced keratoconus four years earlier. He had history of trauma one year later with displaced clear crystalline lens into anterior chamber and graft dehiscence, which was repaired successfully. The graft survived, but patient developed cataract with subluxated lens, for which phacoemulsification with implantation of toric IOL was done. Serial topography showed regular corneal astigmatism of -5.50 diopter (K₁ 42.75 D @130°, K₂ 48.25 D @40°). At 10-month follow-up, the patient has BCVA 20/30 with + 0.75 DS/- 1.75 DC @ 110°. The capsular bag is quite stable with well-centered IOL. Combination of Cionni''s ring with toric IOL could be a good option to manage such complex cases.     

Traumatic globe rupture following penetrating keratoplasty

Purpose To evaluate the mechanism, clinical characteristics, management and visual outcome of ocular trauma following penetrating keratoplasty (PK).Methods Twenty-six patients (13 men, 13 women) who suffered surgical wound dehiscence after PK because of ocular blunt trauma between 1994 and 2001 were included in this retrospective study. Graft dehiscence was managed with primary wound closure in all patients. Visual acuity, intraocular pressure, and funduscopy were evaluated in the follow-up.Results The mean age at trauma was 50±24 years (range 9–88 years). Mean interval between transplantation and trauma was 45.5±64 months (range 1 month to 20 years). Globe rupture occurred at the graft–host junction in all patients. Nine of 13 phakic eyes (69.2%) presented lens expulsion. Eight of nine pseudophakic eyes (88.9%) had lost their implants. Retinal detachment occurred in seven eyes (27%) within 3 months following the trauma. Five patients (19.2%) underwent vitreous surgery for posterior segment damage. Two eyes (7.7%) were regrafted. At the last examination, only seven eyes (27%) had visual acuity of 20/200 or better.Conclusions Traumatic wound dehiscence may occur, and the prognosis is poor after the injury. Globe rupture at the graft–host junction showed persistence of wound weakness even a long time after PK. Prevention of ocular trauma should be performed following PK.None of the authors has any financial interest in this study     

Effect of a standard paired arcuate incision and augmentation sutures on postkeratoplasty astigmatism

To analyze the efficacy of a standardized paired arcuate incision and augmentation suture technique in the treatment of various levels of post-penetrating keratoplasty (PKP) astigmatism.Lions Eye Institute, Royal Perth Hospital, Perth, Australia, and University of Dundee Department of Ophthalmology, Dundee, United Kingdom.A standardized paired arcuate incision and paired augmentation suture technique was used to treat 34 eyes with post-PKP astigmatism ranging from -3.50 to -20.00 diopters (D) at the spectacle plane. The technique consisted of paired arcuate incisions of 3 clock hours, 480 microm deep in the graft-host junction, and 2 pairs of augmentation 10-0 nylon sutures.The mean preoperative cylinder was -9.14 D +/- 4.38 (SD) and the mean postoperative cylinder, -3.59 +/- 1.92 D at the corneal plane after a mean follow-up of 50 +/- 43 weeks. This represents an empirical reduction in mean cylinder of 5. 55 D (60.7%). The Alpins correction index (surgically induced astigmatism [SIA] divided by target induced astigmatism) was calculated for each case, and the mean was 1.01 +/- 0.34, with a median of 0.91. Approximately 53.1% of cases achieved a correction index between 0.80 and 1.20, and the correction index correlated poorly with the initial magnitude of cylinder. A direct numerical relationship between SIA and the initial magnitude of cylinder was observed, although a standard surgical procedure was used in all cases.A simple standardized technique using paired arcuate incisions in the graft-host junction with paired augmentation sutures reduces the amount of cylinder in proportion to the magnitude of the preoperative cylinder and effectively reduces post-PKP astigmatism.     

Standardized semiquantitative analysis of corneal neovascularization using projected corneal photographs--pilot study after perforating corneal keratoplasty before immune reaction

BACKGROUND: A semiquantitative scheme for analysis of corneal neovascularization using projected corneal photographs is demonstrated and tested in a pilot study to analyze occurrence of corneal neovascularization in patients after perforating keratoplasty which subsequently developed transplant rejection. METHODS: Corneal photographs on the slit lamp with diffuse frontal illumination were obtained in a standardized technique. Slides were projected with 100 x magnification and analyzed twice with a 2 months interval. Corneal vessels were graded by two independent observers in each of 12 corneal sectors in a standardized fashion (grade 0: no vessels beyond limbus, 1: vessels between limbus and outer end of a double-running diagonal suture; 2: vessels between outer suture end and graft-host junction; 3: vessels reaching graft-host junction; 4: vessels within donor cornea). All patients with endothelial graft rejection of the prospective Erlangen non-high-risk keratoplasty study were included in a pilot study (1/1997-6/2000: 13 of 325; 4%). One patient without photographs available was excluded. Corneal photographs taken prior to surgery (n = 10), at the last 3 monthly-routine control before (10), at rejection episode (12) and one year later (10) were evaluated for corneal neovascularization. RESULTS: Interobserver correlation at the two assessments was 0.79 and 0.86 (Kendall's Tau B). Correlation between the assessments at the two analyses 2 months apart was 0.8. New vessels with diameter up to 6 microns can be detected. 8 of 12 analyzed patients (67%) with immune reaction after keratoplasty developed corneal neovascularization within 1 year after operation prior to transplant rejection in at least one corneal sector (2.1 +/- 1.9 sectors; 1-6). At time of rejection, new vessels reached the graft-host junction in 2 patients, in 1 patient vessels grew into the donor cornea, whereas in 8 the vessels were seen beyond the outer suture end without reaching host-graft junction (grade I: 1 patient). New vessels usually pointed to the outer suture ends of the double-running suture. CONCLUSIONS: Development of corneal neovascularization e.g. after keratoplasty can be assessed reliably using projected slides of corneal photographs at 100 x magnification. This method has the advantage of being more objective, precise and available compared to simple evaluation at the slit lamp. Postkeratoplasty corneal neovascularization seems to be common in non-high-risk eyes later developing transplant rejection. However, new vessels usually do not reach the host-graft junction. Whether neovascularization after keratoplasty demonstrates a risk factor for subsequent transplant rejection remains to be analyzed in a greater study.     

Evaluation of therapeutic deep anterior lamellar keratoplasty in acute ocular chemical burns

PURPOSE: To evaluate the role of deep anterior lamellar keratoplasty (DALK) in acute ocular chemical burns. METHODS: The study was conducted in 50 eyes of 50 patients (24 male, 26 female) with average age of 38.3+/-14.3 years. DALK in 5 eyes (10%), DALK with quadrant conjunctivo-limbal graft in 25 eyes (50%), and DALK with amniotic membrane in 20 eyes (40%) were performed along with conventional medical therapy. Controls who were matched in all respects (50 eyes) were given medical therapy only as they refused surgical intervention. RESULTS: Follow-up of cases ranged from 6 to 48 months (mean 21.5+/-14.18 months). Forty-three eyes (86%) could be restored with clear cornea as compared to 6% in control group. The visual acuity improvement was seen in 100% with good score (0.49+/-1.46) in DALK group as compared to 18% with low score (0.03+/-0.01) in control group (p<0.0001). Visual acuity improvement in DALK was 6/12 in 19 eyes (38%), 6/24 in 28 eyes (56%), and 6/36 in 3 eyes (6%) but was 3/60-6/60 in 6 eyes (12%) and finger counting only in 3 eyes (6%) in control group. Eyes with advanced grade II and grade III showed better improvement than those with burns of grade IV (p<0.05). The discomfort was relieved and epithelial healing was achieved immediately in DALK as compared to a prolonged course in control group (p<0.0001). Vascularization presented in 38% in DALK with least score (0.13+0.15) as compared to 100% in control group with high score (2.8+/-0.30). Perforation of cornea was seen only in 2 cases (4%) in DALK with low score (0.03+/-0.10) as compared to 88% in control group (1.33+/-0.20). Symblepharon was seen in 2% in DALK group as compared to 62% in control group. CONCLUSIONS: DALK with and without conjunctival or amniotic membrane transplantation is an effective technique in restoring the integrity of the eye with an excellent graft transparency in 86% and improvement in visual acuity in 100% of the acute chemical burns.