Corneal Transplantation Techniques Research Articles

Comparison of Three Different Techniques of Corneal Transplantation for Keratoconus

Comparison of Three Different Techniques of Corneal Transplantation for Keratoconus

Comparison of Three Different Techniques of Corneal Transplantation for Keratoconus

To compare the visual outcomes following deep anterior lamellar keratoplasty (DALK), penetrating keratoplasty (PK), and manual top-hat PK (TH-PK) in subjects undergoing corneal transplantation for keratoconus (KC). A retrospective comparative case series. settings: Cornea clinic at the Toronto Western Hospital. study population: Fifty patients who underwent corneal transplantation for KC: 17 eyes underwent DALK, 20 eyes underwent traditional PK, and 13 had TH-PK. main outcome measures: Preoperative and postoperative uncorrected and best spectacle-corrected visual acuity (UCVA, BSCVA), high-order aberrations (HOA), complication rate, and endothelial cell counts. The median BSCVA at 12 months follow-up was 20/40 in the DALK eyes and 20/30 in the traditional PK and TH-PK eyes. The mean final spherical equivalent power in the three groups was less than -1 diopter (D). The median astigmatism was less than 3.5 D in the three groups. Complication rates were similar for three groups, although the DALK group tended toward more complications. Although DALK and TH-PK procedure results in significantly shorter time to suture removal (P < .01), they caused increased levels of HOAs (P = .02). Endothelial cell counts at 12 months were significantly higher in DALK and TH-PK eyes when compared to the traditional PK eyes (P < .001). DALK, PK, and TH-PK provide comparable visual outcomes in keratoconus patients. Although DALK and TH-PK induce more HOA, they speed up the time to suture removal and provide higher endothelial cell density at one year of follow-up.

Donor dislocation after DSAEK for a failed corneal graft

Descemet stripping automated endothelial keratoplasty (DSAEK) is gradually becoming a preferred technique of corneal transplantation in cases with endothelial dysfunction due to its advantages of early visual rehabilitation, absence of...

One Donor Cornea for 3 Recipients

To describe the use of a single donor corneal tissue in 3 patients with corneal pathologic conditions. A donor corneal tissue was divided into 3 parts using a microkeratome and a trephine. The anterior lamellar disc was transplanted into a patient with macular corneal dystrophy using the automated lamellar therapeutic keratoplasty technique. The posterior lamellar disc was transplanted into a patient with pseudophakic bullous keratopathy using the Descemet stripping automated endothelial keratoplasty technique. The peripheral corneoscleral rim was used for limbal stem cell transplantation in a child with limbal stem cell deficiency. All surgical procedures were performed successfully. At 3 months, the best-corrected visual acuities achieved following automated lamellar therapeutic keratoplasty, Descemet stripping automated endothelial keratoplasty, and limbal stem cell transplantation were 20/60, 20/40, and 20/200, respectively. The advent of customized component corneal transplantation techniques may allow the use of 1 donor cornea to treat multiple patients.

Therapeutic Keratoplasty for Advanced Suppurative Keratitis

To determine indications, therapeutic success, and corneal transplantation techniques for advanced medically uncontrolled infectious keratitis. Retrospective, interventional case series. A review of 92 consecutive patients (1991 to 2002) who underwent therapeutic keratoplasty for acute infectious keratitis performed at Singapore National Eye Centre. Causative organism(s) were identified and outcomes were evaluated in terms of infectious cure (therapeutic success), graft clarity, and visual acuity. Pseudomonas aeruginosa (58.7%) and Fusarium species (32.3%) were the predominant organisms for bacterial and fungal keratitis, respectively. Keratoplasty types included penetrating keratoplasty (PK; n = 80) and lamellar keratoplasty (n = 12). Mean graft diameter was 9.5 mm (range, 5.5 to 14 mm). Seventy-four patients (80.4%) achieved therapeutic success after one keratoplasty procedure, three patients were cured after a second keratoplasty. Life-table survival analysis computed the one-year therapeutic survival for bacterial and fungal keratitis as 76.6% and 72.4%, respectively (P = .76). The Kaplan-Meier one-year survival rate for PK optical clarity was 72%. Twenty-two patients underwent repeat keratoplasty for various reasons (optical, n = 8; recurrent primary infection, n = 7; perforation or subsequent new infections, n = 7). Of the 15 patients for whom therapy failed, 11 had fungal keratitis. Infection recurrence time was four days to one year. Most recurrences (n = 11) appeared within six weeks after surgery. Therapeutic keratoplasty may treat severe, refractory infectious keratitis effectively. High cure rates are achievable, although infection recurrence despite prolonged treatment remains a significant problem in fungal keratitis.

Establishment of a Cultivated Human Conjunctival Epithelium as an Alternative Tissue Source for Autologous Corneal Epithelial Transplantation

The corneal epithelium is essential for maintaining corneal transparency, and efforts have been made to develop improved techniques for corneal epithelial transplantation in patients with total limbal failure. We evaluated the suitability of transplanted cultivated human conjunctival epithelium (HCjE) as a corneal epithelium replacement in rabbits with total corneal and limbal deficiency. HCjE cells, cultivated on human amniotic membrane (AM) to confluence and exposed to an air-liquid interface (air-lifted), were transplanted onto denuded rabbit corneas and monitored for 2 weeks. The cultivated HCjE sheet and the engrafted epithelium were analyzed by immunohistochemistry and transmission electron microscopy (TEM). The transplanted HCjE remained transparent, smooth, and without epithelial defects during the follow-up period. Both the cultivated HCjE cells and the engrafted epithelium manifested five to six layers of stratified squamous epithelium similar in morphology to normal corneal epithelium. The basal cells expressed the putative stem cell markers (ABCG2 and P63) and hemidesmosome and desmosome component proteins. The cytokeratins (CK4, CK13, CK3, and CK12) and MUC4 were found in the engrafted epithelium. However, MUC5AC was not expressed. The results indicate that HCjE cultivated on AM has the potential to be used as an alternative corneal epithelium. The transplantation of cultivated HCjE sheets is a promising technique for the treatment of eyes with limbal failure.

Problems and strategies of corneal surgery in China

Corneal surgery covers corneal refractive surgery and corneal transplantation. Though China has ranked the first in the number of LASIK performed in the world, lack of accredited subspecialty division, surgical admission system and professional administration in the field of refractive surgery prevents the further development of LASIK techniques. However, corneal transplantation techniques of China have been greatly improved in the international level. But the major constrains are legal, storage and screening standards of donor corneas.

Descemet's Stripping With Endothelial Keratoplasty in 50 Eyes: A Refractive Neutral Corneal Transplant

ABSTRACT PURPOSE: To evaluate early visual and refractive outcomes following treatment of corneal endothelial dysfunction with a corneal transplantation technique, Descemet's stripping with endothelial keratoplasty (DSEK). METHODS: Visual and refractive outcomes of the first 50 consecutive cases of DSEK performed by a single surgeon between December 2003 and July 2004 were analyzed retrospectively. The DSEK technique consisted of stripping Descemet's membrane and endothelium from a recipient cornea and transplanting the posterior stroma and endothelium of a donor cornea through a 5-mm incision. RESULTS: Results are reported for 50 eyes in 47 patients (30 women and 17 men). Mean patient age at surgery was 70±12 years (range: 34 to 89 years). Five eyes were treated for corneal edema or bullous keratopathy and 45 for Fuchs' endothelial dystrophy. Seven eyes were phakic and 43 were Pseudophakic. Six months after surgery, mean manifest cylinder was 1.5±0.94 diopters (D), unchanged from preoperative cylinder of 1.5±1.0 D. Mean manifest spherical equivalent refraction was 0.15 ±1.5 D at 6-month follow-up compared with -0.36±1.4 D preoperatively (P=.10) At 3- and 6-month follow-up, significant improvement was noted in mean best spectacle-corrected visual acuity compared with the preoperative mean of 20/100 (P=.007). At 6-month follow-up, 31 (62%) eyes refracted to ≥20/40 and 38 (76%) eyes saw ≥20/50. CONCLUSIONS: Compared to standard penetrating keratoplasty, DSEK causes minimal refractive change and provides rapid visual recovery for patients with endothelial dysfunction. This technique maintains the structural integrity of the cornea by preserving the recipient's epithelium, Bowman's layer, and entire stromal thickness. [J Refract Surg. 2005;21:339-345.]

Descemet's Stripping With Endothelial Keratoplasty in 50 Eyes: A Refractive Neutral Corneal Transplant/Reply

To evaluate early visual and refractive outcomes following treatment of corneal endothelial dysfunction with a corneal transplantation technique, Descemet's stripping with endothelial keratoplasty (DSEK). Visual and refractive outcomes of the first 50 consecutive cases of DSEK performed by a single surgeon between December 2003 and July 2004 were analyzed retrospectively. The DSEK technique consisted of stripping Descemet's membrane and endothelium from a recipient cornea and transplanting the posterior stroma and endothelium of a donor cornea through a 5-mm incision. Results are reported for 50 eyes in 47 patients (30 women and 17 men). Mean patient age at surgery was 70 +/- 12 years (range: 34 to 89 years). Five eyes were treated for corneal edema or bullous keratopathy and 45 for Fuchs' endothelial dystrophy. Seven eyes were phakic and 43 were pseudophakic. Six months after surgery, mean manifest cylinder was 1.5 +/- 0.94 diopters (D), unchanged from preoperative cylinder of 1.5 +/- 1.0 D. Mean manifest spherical equivalent refraction was 0.15 +/- 1.5 D at 6-month follow-up compared with -0.36 +/- 1.4 D preoperatively (P = .10) At 3- and 6-month follow-up, significant improvement was noted in mean best spectacle-corrected visual acuity compared with the preoperative mean of 20/100 (P = .007). At 6-month follow-up, 31 (62%) eyes refracted to > or = 20/40 and 38 (76%) eyes saw > or = 20/50. Compared to standard penetrating keratoplasty, DSEK causes minimal refractive change and provides rapid visual recovery for patients with endothelial dysfunction. This technique maintains the structural integrity of the cornea by preserving the recipient's epithelium, Bowman's layer, and entire stromal thickness.

Posterior lamellar keratoplasty for a case of pseudophakic bullous keratopathy

PURPOSE: To describe a new surgical technique for posterior corneal transplantation. METHODS: An elderly patient had painful, pseudophakic bullous keratopathy with low visual potential. Through a 9.0-mm scleral tunnel incision, a midstromal pocket was dissected across the cornea, and a posterior lamellar disk 7.0-mm in diameter, which consisted of posterior stroma, Descemet membrane, and endothelium, was excised. A similarly shaped donor posterior disk was implanted in the recipient opening without suture fixation, and the scleral incision was sutured. RESULTS: Throughout the postoperative period, the posterior corneal transplant remained clear and in position. Three months after surgery, the “suture-in” astigmatic error was 3.5 diopters. Pachymetry measured 0.44 mm. CONCLUSION: Posterior lamellar keratoplasty may be a new surgical approach with which to manage corneal endothelial disorders.

A New Elliptical Excision for Corneal Transplantation Using an Excimer Laser

To the Editor. —Current standard corneal transplantation techniques use circular, round, mechanical trephines either operated by hand or motor driven, under visual control through the operating microscope. The anatomic and functional results of this sight-improving procedure are acceptable. 1 The two major problems of the procedure are disturbing astigmatism and immunologic graft rejections. Excessive corneal astigmatism and optical irregularities are caused by incongruent cut surfaces of donor and patient corneas and disparities in corneal thickness. 1 Immunologic graft rejection occurs in 10% of avascular corneas and increases in frequency in vascularized corneas and as the diameter of the corneal graft increases. While for optical purposes it is desirable to have the corneal graft as large as possible, immunologic requirements aim for the opposite result. The ultraviolet excimer laser technique enables us to overcome the mechanical limitations of the trephination procedure and to produce noncircular trephinations. 2,3 We now introduce a

A Simplified Technique for Corneal Transplantation : Employing a Contact‐Lens Splint: An Experimental Study

A Simplified Technique for Corneal Transplantation : Employing a Contact‐Lens Splint: An Experimental Study

Technique of Corneal Transplantation

Technique of Corneal Transplantation

Remarks on the Technique of Corneal Transplantation

Remarks on the Technique of Corneal Transplantation

Remarks on the Technique of Corneal Transplantation

Remarks on the Technique of Corneal Transplantation

Surgical Technique of Corneal Transplantation in Rabbits : A Discussion of the Problems Encountered and Suggestions for their Solution

Surgical Technique of Corneal Transplantation in Rabbits : A Discussion of the Problems Encountered and Suggestions for their Solution

Keratoplasty : Comments on the technique of corneal transplantation. Source and preservation of donor's material. Report of new instruments. Part II

Keratoplasty : Comments on the technique of corneal transplantation. Source and preservation of donor's material. Report of new instruments. Part II

Keratoplasty : Comments on the technique of corneal transplantation. Source and preservation of donor's material. Report of new instruments

Keratoplasty : Comments on the technique of corneal transplantation. Source and preservation of donor's material. Report of new instruments