Optimising keratoplasty for Peters' anomaly in infants using spectral-domain optical coherence tomography.

PURPOSE: To present in vivo anterior segment optical coherence tomography (OCT) features of infants with Peters' anomaly obtained during presurgical examination under general anaesthesia, and to evaluate the impact of OCT features on surgical decision making. METHODS: This is a single-centre, consecutive, observational case series including 44 eyes of 27 infants with Peters' anomaly (5-18 months) undergoing keratoplasty. Medical records of patients were reviewed retrospectively. Clinical features and OCT findings, along with their impact on surgical decision-making were analysed. RESULTS: Of 27 patients, 10 had unilateral and 17 had bilateral disease. Two patients with mild disease (three eyes) had a posterior corneal defect with leukoma (2/27, 7.4%). Twenty patients (32 eyes) with iridocorneal adhesions were classified as having moderate Peters' anomaly (20/27, 74.1%) and five patients (nine eyes) with lenticulocorneal adhesions were classified as having severe Peters' anomaly (5/27, 18.5%). The range of angle closure, anterior chamber depth and maximum iridocorneal adhesion length (all p<0.001) were significantly different among groups, indicating that they might serve as novel OCT parameters for assessing the severity of Peters' anomaly. The surgical approach in seven patients (21.2%) was altered in response to intraoperative OCT findings, which provided information regarding the anatomical structure of the anterior chamber not provided by the surgical microscope. The use of OCT prevented unnecessary cataract surgeries in five patients. CONCLUSIONS: Our study showed that information gained from OCT under anaesthesia allows surgeons to classify type and severity of Peters' anomaly and supports surgical decision making.

Cornea donors who have had prior refractive surgery: data from the Eye Bank Association of America.

PURPOSE OF REVIEW: Millions of Americans have undergone refractive surgeries, including radial keratotomy, photorefractive keratectomy, and laser-assisted in situ keratomileusis. Eye Bank Association of America medical standards do not permit corneas from patients who have undergone refractive procedures to be used in penetrating keratoplasty, anterior lamellar keratoplasty, or tectonic grafting procedures. Such corneas, can, however, be used for endothelial corneal transplantation. The objective of this article is to provide an update on current trends for the screening and usage of corneas that have undergone refractive surgery. RECENT FINDINGS: Several case reports have highlighted the difficulty in using postrefractive surgery corneas in penetrating keratoplasty. However, tissue with anterior stromal flaws, including a history of refractive surgery, has been used in endothelial keratoplasty with equivalent outcomes in topography, endothelial cell count, and visual acuity. Many modalities for proper identification of postmortem donor corneas that have undergone refractive surgery have been studied. SUMMARY: Corneas with a history of refractive surgery have found use in endothelial keratoplasty. Multiple objective methods of tissue identification have been investigated to avoid the use of these corneas in penetrating or anterior keratoplasty surgeries.

[Functional results of contact lens correction and penetrating keratoplasty in keratoconus. Report 1. Analysis of resolution ability of the eye].

Comparative analysis of functional results of contact lens correction and penetrating keratoplasty (PKP) in keratoconus are presented. To assess resolution ability we considered visual acuity and contrast sensitivity. 117 patients (219 eyes) with stage I-IV keratoconus, wearing rigid gas-permeable contact lenses (RPCL), and 60 patients (64 eyes) after PKP were examined. In 69% patients after PKP non-corrected visual acuity (NCVA) was 0.1 or more and mean best corrected visual acuity (BCVA) was 0.63, that is similar to efficacy of contact lens correction in stage III-IV keratoconus. In 31% patients NCVA after PKP was less than 0.1 due to significant refractive arrow, visual rehabilitation of these patients required use of RPCL or refractive surgery. Contrast sensitivity in medium frequencies after PKP was almost similar to that of contact lens correction in stage III keratoconus, and in high frequencies it was close to that of stage IV.

[Functional results of contact lens correction and penetrating keratoplasty in keratoconus. Report 2. Wavefront analysis].

Comparative analysis of optic aberrations in contact lens correction and after penetrating keratoplasty (PKP) in keratoconus are presented. 117 patients (219 eyes) with stage I-IV keratoconus, wearing rigid gas-permeable contact lenses (RPCL), and 60 patients (64 eyes) after PKP were examined using OPD Scan (NIDEK, Japan) to assess aberration characteristics. Total optic aberrations and higher-order aberrations of ocular and corneal wavefront were significantly increased after PKP compared to those in patients with I-III stage keratoconus wearing RGCL. Astigmatic aberrations after surgery are increased compared to that in patients wearing RGCL regardless of keratoconus stage. Generally, according to objective aberrometry efficacy of PKP is similar to that of contact lens correction in IV stage keratoconus.

Robotic microsurgery: corneal transplantation.

BACKGROUND: Robotic ocular microsurgery including corneal suturing has been proven to be feasible in porcine eyes. AIM: To determine whether or not bimanual teleoperated robotic penetrating keratoplasty (PK) can be performed in porcine and human eyes. METHODS: Three arms of the da Vinci surgical robot were loaded with a dual-channel video and two, 360 degrees -rotating, 8 mm, wrested-end effector instruments and placed over porcine eyes or over a human cadaver head. The surgeon remotely performed mechanical trephination, cardinal sutures, continuous 10.0 nylon sutures and suture adjustments on both eyes. The procedures were documented with still and video photography. RESULTS: Using the da Vinci robot, penetrating keratoplasty procedures were successfully performed on both porcine eyes and human eyes in natural anatomical conditions. The precise placement of continuous sutures was facilitated by the wrested-end forceps. Orbital rims and nose did not limit surgical motions. CONCLUSION: Teleoperated robotic penetrating keratoplasty is technically feasible in humans. Further studies are pending to implement the procedure with femtosecond laser and other automated steps.

Retrospective contralateral study comparing descemet stripping automated endothelial keratoplasty with penetrating keratoplasty.

PURPOSE: To compare the visual outcomes and complications rate after penetrating keratoplasty (PKP) and Descemet stripping automated endothelial keratoplasty (DSAEK), in the fellow eye of the same subjects, and to evaluate the patient's perspective on these operations. METHODS: A retrospective cohort study was undertaken in the Cornea Clinic at the Toronto Western Hospital. We reviewed the records of 12 patients (24 eyes) who underwent PKP in one eye and DSAEK surgery in their fellow eye. Patient's satisfaction for both procedures was evaluated using a subjective questionnaire. These techniques were compared for intraoperative and postoperative complications and visual and refractive outcomes including contrast acuity, contrast threshold, and high-order ocular aberrations (HOA). RESULTS: All the patients in this study preferred the DSAEK operation. They reported faster recovery time [1.5 week in the DSAEK vs 5.3 weeks in the PKP operation (P = 0.01)], significantly less pain, and better visual outcomes with the DSAEK operation. Uncorrected visual acuity and best-corrected visual acuity were significantly better in the DSAEK operated eyes. The DSAEK surgery was associated with significantly less astigmatism (P = 0.0003) and ametropia. Contrast acuity was significantly better in the eye that underwent DSAEK procedure (P < 0.05), whereas contrast threshold was better in the PKP eye. The PKP operated eyes demonstrated increased level of HOA. CONCLUSIONS: Patients preferred the DSAEK operation compared with PKP. Better uncorrected visual acuity, best-corrected visual acuity, and contrast acuity together with avoidance of surgery-induced astigmatism and HOA are the main benefits of the DSAEK technique.

The value-based medicine comparative effectiveness and cost-effectiveness of penetrating keratoplasty for keratoconus.

OBJECTIVE: To perform a base case, comparative effectiveness, and cost-effectiveness (cost-utility) analysis of penetrating keratoplasty for patients with severe keratoconus. METHODS: Visual acuity data were obtained from a large, retrospective multicenter study in which patients with keratoconus with less than 20/40 best corrected visual acuity and/or the inability to wear contact lenses underwent penetrating keratoplasty, with an average follow-up of 2.1 years. The results were combined with other retrospective studies investigating complication rates of penetrating keratoplasty. The data were then incorporated into a cost-utility model using patient preference-based, time trade-off utilities, computer-based decision analysis, and a net present value model to account for the time value of outcomes and money. The comparative effectiveness of the intervention is expressed in quality-of-life gain and QALYs (quality-adjusted life-years), and the cost-effectiveness results are expressed in the outcome of $/QALY (dollars spent per QALY). RESULTS: Penetrating keratoplasty in 1 eye for patients with severe keratoconus results in a comparative effectiveness (value gain) of 16.5% improvement in quality of life every day over the 44-year life expectancy of the average patient with severe keratoconus. Discounting the total value gain of 5.36 QALYs at a 3% annual discount rate yields 3.05 QALYs gained. The incremental cost for penetrating keratoplasty, including all complications, is $5934 ($5913 discounted at 3% per year). Thus, the incremental cost-utility (discounted at 3% annually) for this intervention is $5913/3.05 QALYs = $1942/QALY. If both eyes undergo corneal transplant, the total discounted value gain is 30% and the overall cost-utility is $2003. Surgery on the second eye confers a total discounted value gain of 2.5 QALYs, yielding a quality-of-life gain of 11.6% and a discounted cost-utility of $2238/QALY. CONCLUSIONS: Penetrating keratoplasty for patients with severe keratoconus seems to be a comparatively effective and cost-effective procedure when compared with other interventions across different medical specialties.

Endothelial keratoplasty using donor tissue not suitable for full-thickness penetrating keratoplasty.

PURPOSE: To evaluate the use of corneal donor tissue deemed unsuitable for full-thickness penetrating keratoplasty (PK) for use in deep lamellar endothelial keratoplasty (DLEK) and to compare postoperative results to those of DLEK surgery using donor tissue that is suitable for PK. METHODS: Small-incision DLEK surgery was performed using 39 donor corneas unsuitable for PK. Thirty-five donors had anterior scars or opacities, 3 donors had pterygia within the 8-mm zone, and 1 had prior LASIK. All donor preparation was completed by manual stromal dissection. The DLEK surgical and postoperative courses were reviewed. Preoperative and 6-month postoperative results of this study group were compared with a control group consisting of the first 55 consecutive small-incision DLEK patients receiving donor corneas that had no criteria excluding them from use in PK. Four eyes in the study group and 1 eye in the control group had the confounding variables of the presence of an anterior-chamber lens or surgical vitrectomy with macular disease in the recipient eye. RESULTS: There was no significant difference in preoperative measurements of best spectacle-corrected visual acuity (BSCVA; P = 0.372), donor endothelial cell density (ECD; P = 0.749), or corneal topography [surface regularity index (SRI), P = 0.485; or surface asymmetry index (SAI), P = 0.154] between the 2 groups. For the patients receiving corneas deemed unacceptable for PK, at 6 months after surgery, the vision (P = 0.002) and corneal topography measurements improved significantly from before surgery (SRI, P < 0.001; SAI, P < 0.001), and there was no significant change in refractive astigmatism (P = 0.240). There was a significant difference in the vision at 6 months postoperatively between the overall study group and the control group, with the mean vision of the study group at 20/56 and the control group at 20/43 (P = 0.015). If eyes with known cystoid macular edema (CME) and vitrectomy are removed from each group, there is no significant difference in vision at 6 months between the study group and the control group (P = 0.110), with the average BSCVA of those receiving donor corneas unsuitable for PK equal to 20/48 (range, 20/25-20/200) and the average vision for those receiving PK-acceptable donor tissue equal to 20/43 (range, 20/20-20/80). The 6-month average refractive astigmatism of the study group was 1.12 +/- 0.99 D (range, 0.00-4.00 D), and the average endothelial cell count was 2064 +/- 396 cells/mm(2) (range, 1208-2957 cells/mm(2)). There was no significant difference in 6-month postoperative endothelial cell count (P = 0.443), refractive astigmatism (P = 0.567), or corneal topography (SRI, P = 0.332; SAI, P = 0.110) in study patients who received corneas unsuitable for PK compared with control patients who received corneas suitable for PK. CONCLUSIONS: Endothelial keratoplasty such as DLEK surgery with manual donor preparation broadens the donor pool by enabling corneas that cannot be used for PK to be used for selective endothelial transplantation without deleterious postoperative results.

Avaliação de córneas doadoras em lâmpada de fenda e microscopia especular durante o período de armazenamento / Evaluation of corneal tissue by slit lamp and specular microscopy during the preservation period

OBJETIVO: Analisar as mudanças de notas de avaliação por meio da biomicroscopia e microscopia eletrônica de córneas doadas, e desta forma assegurar córnea doadora de padrão satisfatório ao paciente. MÉTODOS: Foram avaliadas prospectivamente 203 córneas entre setembro de 2002 e fevereiro de 2003, doadas ao Banco de Olhos de Sorocaba. A avaliação constava de graduação de 0 a 3 que variava mediante os seguintes fatores: exposição e defeito epitelial, opacidade e infiltrado estromal, dobras ou estrias de Descemet, pleomorfismo, polimegatismo e guttata, "endothelial snail track", edema, refletividade. Os dados encontrados foram correlacionados com o intervalo entre óbito e preservação, contagem de células endoteliais e idade dos doadores. RESULTADOS: Duzentos e três córneas foram avaliadas. A idade média dos doadores foi de 55 anos (dp=14,8 anos). O tempo médio do óbito à preservação foi de 9,1 h (mínimo de 2 horas e máximo de 25 horas). Oitenta e seis córneas sofreram pioras de avaliação, sendo que 66,3 por cento delas tinham até 2.500 células endoteliais e 59,3 por cento delas tinham tempo superior a 6 horas entre o óbito e a preservação. O dia da mudança teve por mediana 5. CONCLUSÕES: Córneas de doadores mais jovens possuem significativamente avaliações melhores que doadores mais velhos. O tempo médio de mudança de avaliação foi com 5 dias em 50 por cento das córneas, entretanto, expressiva parcela de córneas apresentou alteração nos dias 6°, 7° e 8°. Córneas preservadas após 6 horas do óbito têm maior tendência à perda de células e redução dos índices de avaliação.

PURPOSE: To analyze changes evaluation of corneal grafts by slit lamp and electron microscopy examination in order to ensure a donor cornea of good quality level for the patient. METHODS: 203 córneas donated to the Sorocaba Eye Bank between September 2002 and February 2003 were prospectively evaluated. The evaluation was graded from 0 to 3 according to the following factors: exposure and epithelial damage, stromal opacity, Descemet folds, pleomorphism, polymegatism and guttata, endothelial snail track, edema, reflectivity. The data were correlated with time between death and preservation, endothelial cell count and donor's age. RESULTS: 203 corneas were evaluated. The mean age of donors was 55 years (dp= 14.8 years). The mean time between death and preservation was 9.1 h (minimum of 2 h and maximum of 25 h). Eighty-six corneas suffered worsening of evaluation, whereby 66.3 percent had less than 2,500 endothelial cell count and 59.3 percent presented time between death and preservation over 6 hours. The mean day of the grading change was the 5th. CONCLUSIONS: Corneal grafts from younger donors had significantly better evaluation than those of older donors. The mean time of the evaluation change was on the 5th day in 50 percent of the corneas, however, an expressive number of corneas suffered changes on the 6th, 7th and 8th day. Corneal graft preserved after 6 hours of death had a greater tendency to lower cell count and to decrease in evaluation grades.

Contrast sensitivity in deep anterior lamellar keratoplasty versus penetrating keratoplasty.

PURPOSE: To compare the measurements of contrast sensitivity at a distance in patients submitted to penetrating keratoplasty versus patients submitted to deep anterior lamellar keratoplasty for keratoconus treatment. METHODS: Contrast sensitivity of 15 subjects submitted to penetrating keratoplasty and 15 subjects submitted to deep anterior lamellar keratoplasty have been analyzed through the Functional Acuity Contrast Test (F.A.C.T) 301. RESULTS: There was no statistically significant difference between the measurements for penetrating keratoplasty and deep anterior lamellar keratoplasty. CONCLUSION: Contrast sensitivity was similar among the subjects submitted to penetrating keratoplasty and to deep anterior lamellar keratoplasty for keratoconus treatment.

Contrast sensitivity in deep anterior lamellar keratoplasty versus penetrating keratoplasty

PURPOSE: To compare the measurements of contrast sensitivity at a distance in patients submitted to penetrating keratoplasty versus patients submitted to deep anterior lamellar keratoplasty for keratoconus treatment. METHODS: Contrast sensitivity of 15 subjects submitted to penetrating keratoplasty and 15 subjects submitted to deep anterior lamellar keratoplasty have been analyzed through the Functional Acuity Contrast Test (F.A.C.T®) 301. RESULTS: There was no statistically significant difference between the measurements for penetrating keratoplasty and deep anterior lamellar keratoplasty. CONCLUSION: Contrast sensitivity was similar among the subjects submitted to penetrating keratoplasty and to deep anterior lamellar keratoplasty for keratoconus treatment.

OBJETIVO: Comparar as medidas de sensibilidade ao contraste à distância entre pacientes submetidos à ceratoplastia penetrante e pacientes submetidos à ceratoplastia lamelar anterior profunda para tratamento do ceratocone. MÉTODOS: Sensibilidades ao contraste de 15 pacientes submetidos à ceratoplastia penetrante e de 15 pacientes submetidos à ceratoplastia lamelar anterior profunda foram analisadas através do Functional Acuity Contrast Test (F.A.C.T®) 301. RESULTADOS: Não existiu diferença estatisticamente significante entre as medidas em ceratoplastia penetrante e ceratoplastia lamelar anterior profunda. CONCLUSÃO: Sensibilidade ao contraste foi similar entre os pacientes submetidos à ceratoplastia penetrante e à ceratoplastia lamelar anterior profunda para tratamento do ceratocone.

Avaliação da exeqüibilidade, eficácia e segurança do transplante lamelar semi-automatizado de córnea / Evaluation of performance, efficacy and safety of semi-automated lamellar keratoplasty

OBJETIVO: Avaliar a exeqüibilidade, eficácia e segurança do uso de microcerátomo e câmara anterior artificial para o transplante lamelar (sistema ALTK®). MÉTODOS: 21 olhos com opacidades corneanas superficiais foram submetidos ao transplante lamelar semi-automatizado de córnea. Nos olhos receptores a ceratectomia foi realizada de modo semelhante a uma cirurgia refrativa. As lamelas doadoras foram obtidas a partir de botões esclero-corneanos utilizando o mesmo microcerátomo e uma câmara anterior artificial. As medidas das espessuras corneanas foram feitas através da biomicroscopia ultra-sônica. RESULTADOS: As cirurgias obtiveram êxito em 19 olhos. Em 80 por cento das lamelas obtidas em córneas doadoras e em 84,2 por cento das lamelas em olhos receptores houve uma variação de até 0,5 mm do diâmetro desejado. Verificou-se alta semelhança entre as espessuras das lamelas obtidas nos olhos receptores e lamelas doadoras. Obteve-se acuidade visual corrigida pós-operatória igual ou superior a 20/40 em 52,6 por cento dos olhos. Foram observadas complicações como diâmetro inadequado da lamela, perfuração intra-operatória no olho receptor e ectasia corneana pós-operatória (um caso). CONCLUSÕES: O transplante lamelar semi-automatizado de córnea mostrou-se exequível pela reprodutibilidade das espessuras e diâmetros das lamelas; eficaz pela melhora da acuidade visual pós-operatória e seguro, devido ao baixo índice de complicações cirúrgicas.

PURPOSE: To evaluate the feasibility, efficacy and safety of a manual microkeratome and an artificial anterior chamber for lamellar keratoplasty (ALTK® system). METHODS: Twenty-one eyes with superficial corneal opacities were submitted to semi-automated lamellar keratectomy. In recipient eyes keratectomy was performed as in refractive surgery. The donor flap was removed from the preserved corneal shell using the same microkeratome and an artificial anterior chamber. Lamella thickness was measured through ultrasound biomicroscopy (UBM) after surgery. RESULTS: The surgeries were accomplished successfully in 19 eyes. 80 percent of the flaps obtained in donated corneas and 84.2 percent of the flaps in recipient eyes had an up to 0.5 mm variation variation of the desired diameter. A high similarity in flap thickness between the donor flap and the recipient cornea was obtained. Postoperative visual acuity of 20/40 or better was observed in 52.6 percent of the eyes. Complications such as undesired diameter of the flap, a case of perforation in the recipient eye and a case of cornea ectasia were observed. CONCLUSION: The semi-automated lamellar keratoplasty ALTK® system showed to be feasible due to the predictability and reproducibility regarding lamella thickness and diameter, efficient in the improvement of postoperative visual acuity and safe due to the low level surgical complication.

Penetrating keratoplasty: outcomes from a corneal unit compared to national data.

AIMS: To determine long term graft survival rates and visual results for different indications for penetrating keratoplasty from a single institution over 10 years and compare these to national outcome data. METHODS: Retrospective chart analysis. 784 records were available for review of 1096 consecutive penetrating keratoplasty procedures performed between 1990 and 1999 (72%). Outcomes of graft survival, visual acuity, and astigmatism were analysed and compared to national outcome data supplied by the UK Transplant Service. RESULTS: At 5 year follow up, overall graft survival was 66%. This was subdivided into 98% for keratoconus, 86% for viral keratitis, 85% for Fuchs' dystrophy, 84% for pseudophakic bullous keratopathy, 55% for regrafts, and 57% for other diagnoses. There was a significantly higher graft survival rate for all diagnostic subgroups except Fuchs' dystrophy at 3 years of follow up compared to the national average. Best corrected visual acuity at 5 years was 6/18 or better in 53% of cases. The mean keratometric astigmatism was 3.4 dioptres. CONCLUSION: Penetrating keratoplasty is a safe and effective treatment for selected corneal disorders. Penetrating keratoplasty for viral keratitis may achieve good results with long term antiviral treatment. Patients may achieve better outcomes if their surgery is performed at specialist centres.

[Evaluation of performance, efficacy and safety of semi-automated lamellar keratoplasty]. / Avaliação da exeqüibilidade, eficácia e segurança do transplante lamelar semi-automatizado de córnea.

PURPOSE: To evaluate the feasibility, efficacy and safety of a manual microkeratome and an artificial anterior chamber for lamellar keratoplasty (ALTK system). METHODS: Twenty-one eyes with superficial corneal opacities were submitted to semi-automated lamellar keratectomy. In recipient eyes keratectomy was performed as in refractive surgery. The donor flap was removed from the preserved corneal shell using the same microkeratome and an artificial anterior chamber. Lamella thickness was measured through ultrasound biomicroscopy (UBM) after surgery. RESULTS: The surgeries were accomplished successfully in 19 eyes. 80% of the flaps obtained in donated corneas and 84.2% of the flaps in recipient eyes had an up to 0.5 mm variation variation of the desired diameter. A high similarity in flap thickness between the donor flap and the recipient cornea was obtained. Postoperative visual acuity of 20/40 or better was observed in 52.6% of the eyes. Complications such as undesired diameter of the flap, a case of perforation in the recipient eye and a case of cornea ectasia were observed. CONCLUSION: The semi-automated lamellar keratoplasty ALTK system showed to be feasible due to the predictability and reproducibility regarding lamella thickness and diameter, efficient in the improvement of postoperative visual acuity and safe due to the low level surgical complication.

The importance of various factors relating to the morphological quality of corneas used for PKP by the Warsaw Eye Bank from 1996 to 2002.

To examine the effect of various factors such as: donor's age, cause of death, time between death and preservation and duration of preservation on the morphological quality of corneas used for Penetrating Keratoplasty (PKP). Our purpose was to assess the role of the above factors influencing the corneal overall rating and endothelial cell density. The present data regarding the donor's age and time between death and preservation of corneas obtained from eye banks belonging to the European Eye Bank Association and Polish eye banks were compared. Corneoscleral buttons and data concerning donors were obtained by eye bank technicians and collected in Warsaw Eye Bank in the years 1996-2002. The quality of the corneas recovered was evaluated by means of slit lamp Nikon NS-IV and specular microscope KONAN. Cardiorespiratory failure and cardiac arrest were the most frequent cause of the donors' death. In many cases donors with confirmed brain death who were given the corneas, were also donors of internal organs like heart, kidneys, pancreas and liver. The number of donors with disseminated neoplasm disease--complete disadvantage for removing corneas increased during the eye bank activity. The epithelial and endothelial layers sometimes underwent mechanical trauma in the group of donors because of sudden death. From 1996 to 2002 more than 50% of the donors were over 60 years of age. There were many problems with receiving corneas from younger donors. The overall rating tissues which were obtained in a very short time after death (to 5 hours) was higher (Excellent and Very Good) compared with corneas removed 8-12 hours after the donor's death. The increasing percentage of endothelial cell loss was observed in all the corneas after about 7 days of preservation in the medium. The mean endothelial cell density slightly decreased with donor's age, but its suggested range of the factors possibility of finding the corneas with high number of endothelial cell density both in younger and older donors. The average time from death to preservation was similar in eye banks preserving corneas at +4 degrees C (8-10 hours) compared with eye banks using mainly the organ culture method. The rating of the morphological state of corneas suitable for PKP depends on the time between death and preservation, donor's age, cause of death and time of preservation of corneas. Corneas obtained shortly after the donor's death showed a higher endothelial cell density and better overall rating than those removed after relatively longer period after the donor's death. An increasing percentage of endothelial cell loss was observed after 7 days of preservation independent of other factors.

Outcomes of corneal transplantation: a corneal surgeon vs the general ophthalmologist.

AIMS: The aim of this study was to examine the outcomes of corneal transplantation in cases performed by a group of general ophthalmologists and those performed by an ophthalmologist with a subspecialist interest in corneal surgery. METHODS: A retrospective analysis of the outcomes in corneal transplantation was carried out for a 4-year period in three separate units in South Wales. In addition to patient demographic details, the primary diagnosis, type of keratoplasty performed, and outcome of surgery were noted. The data were analysed statistically by the Mann-Whitney U-test (one-tailed). RESULTS: Group A (n=35) was defined as those patients whose surgery was performed by a general ophthalmologist. There were seven surgeons in this group with a mean of five procedures each over the study period. Group B (n=54) were all operated on by the same surgeon. The mean age in both groups was similar with group A comprising of 66% males with 50% males in group B. The commonest indication for surgery in both groups was endothelial cell failure In group A, graft clarity at 1 year was 83% for all aetiologies and 73% at 2 years. In group B, the results were 97 and 92%, respectively. In group A, overall 56% achieved 6/18 or better compared with 68% in group B. In group A 73% had an improvement of one or more lines compared with 84% in group B (P=0.085). Reasons for graft failure in both groups were similar. CONCLUSION: The success rate of corneal transplantation carried out by general ophthalmologists in this study is reduced when compared with cases performed by a corneal surgeon. The explanation for this is not clear, but is undoubtedly multifactorial.

Symmetrical marking of both donor and recipient corneas in penetrating keratoplasty.

The symmetrical marking of both the donor and the recipient corneas aids in the proper alignment of the donor cornea within the recipient opening. The second stitch in a penetrating keratoplasty is the most important stitch for the proper alignment of the donor cornea within the recipient opening. If the second stitch is placed too far to the right or left, there will be a gap on one side and an override on the other side. This misalignment is likely to result in a distortion of the corneal surface contour. The proper alignment can be made even more difficult if the recipient opening is distorted. The proper alignment can be facilitated by symmetrically marking both donor and recipient corneas. A simple surgical technique is described to clarify and emphasize this very important principle of penetrating keratoplasty--the alignment of the donor cornea within the recipient opening.

The handling of corneal donor tissue before penetrating keratoplasty.

1. Corneal tissue must meet quality standards established by Federal Regulations and state laws. 2. Documented information regarding eye bank tissue is privileged and confidential. 3. Media used to store corneal tissue must meet Food and Drug Administration (FDA) Good Manufacturing Practices standards.