G. Van Rij

Femtosecond laser-assisted inverted mushroom keratoplasty.

PURPOSE To evaluate best-corrected visual acuity (BCVA), refractive outcome, corneal topography, optical coherence tomography, and endothelial cell density 12 months after femtosecond laser-assisted inverted mushroom keratoplasty. METHODS We performed a prospective study of a surgical case series of 5 patients undergoing femtosecond laser-assisted inverted mushroom keratoplasty for pseudophakic bullous keratopathy or pre-Descemet X-linked ichthyosis. The femtosecond laser was used to create a top-hat configuration in the donor cornea and recipient cornea. Laser parameters were as follows: energy, 4.0 (anterior inner vertical side cut and horizontal lamellar cut) and 7.0 microJ (posterior outer vertical side cut); spiral pattern with a firing rate of 15 kHz. The size of the anterior inner diameter was 7.4 mm in the donor cornea and 7.0 mm in the recipient cornea. The posterior outer diameter was 9.0 mm in all eyes. RESULTS At 6 and 12 months after surgery, all corneal grafts were clear and showed an excellent adaptation of the lamellar donor and recipient wound surfaces. At 12 months postoperatively, BCVA averaged 20/32 (range, 20/60-20/20), refractive cylinder averaged -3.20 +/- 2.0 D, topographical cylinder averaged 3.26 +/- 2.1 D, and the mean endothelial cell density was 1793 +/- 491 cells/mm2 (range, 954-2237 cells/mm2). The mean central corneal thickness and thickness of the posterior shelf was 517 +/- 3 and 175 +/- 8 microm, respectively. CONCLUSIONS The femtosecond laser-assisted inverted mushroom keratoplasty shows good promise in surgical treatment of corneal diseases. The multiplanar fit between the donor and recipient cornea allows early suture removal and visual rehabilitation.

Effect of indomethacin in preventing surgically induced miosis.

A double-blind study was performed on 64 patients to assess the effect of preoperative indomethacin in comparison with a placebo in preventing surgically induced miosis during extracapsular cataract extraction. One drop of indomethacin or placebo was instilled at 7.00 p.m. and at 9.00 p.m. the night before surgery and 2 hours, 1 hour, and 15 minutes preoperatively. The pupil diameter was recorded at different stages of the operation. It was found that indomethacin as compared with the placebo significantly reduced the amount of pupil constriction during the operation, making the removal of lens material and the implantation of an intraocular lens easier. The indomethacin is thought to act by inhibiting prostaglandin synthesis caused by iris trauma during surgery.

Silicone oil keratopathy: indications for keratoplasty.

A penetrating corneal graft was performed in 12 patients for corneal opacification induced by silicone oil. The patients were all aphakic. They had had vitrectomy and silicone oil injection for complicated retinal detachment, often with periretinal proliferation. The average follow-up time was 13.7 months, during which four out of 11 grafts failed (one case was lost to follow-up). One patient developed severe calcific band keratopathy, and three grafts failed from endothelial decompensation. Changes induced by silicone oil include band keratopathy, thinning, and endothelial damage. The indications for keratoplasty for these corneal changes are discussed.

Anticoagulant therapy and cataract surgery

A questionnaire was sent round to the 200 members of the Netherlands Intraocular Implant Club (NIOIC), in which they were asked about the policy followed in 1988 with regard to anticoagulant therapy (ACT) and the use of aspirin before and after cataract surgery. Ninety-nine formulas were returned, of which ninety-two were suitable for analysis. It appeared that 62% of the eye surgeons stopped ACT, whereas only 33% stopped the use of aspirin. After stopping ACT nine, in some cases serious, systemic complications arose. The continuation of ACT led to 3 ocular complications. It would appear that continuation of ACT and the use of aspirin is to be recommended.

CAUSES OF HIGH ASTIGMATISM AFTER PENETRATING KERATOPLASTY

We retrospectively evaluated the factors which might have caused excessive corneal astigmatism after penetrating keratoplasty (PKP) in 29 eyes, in which surgical correction of astigmatism was indicated. In 18 eyes high astigmatism (5 diopters or more) existed before suture removal probably due to graft elevation (3×), wound dehiscence (3×), wound configuration abnormalities such as ovality/overcut (8×), and a thin recipient cornea (2×). The cause was unknown in 2 eyes. In 19 eyes the astigmatism considerably increased after all sutures were removed; astigmatism increased an average of 8.8 diopters (range, 5 to 16.5 D). Ten of these 19 patients showed graft elevation, despite the fact that the sutures were only removed after an average 22.9 months. In 3 other patients the astigmatism gradually increased over the years, long after suture removal; two of these showed graft elevation. The study demonstrates the possible instability of keratoplasty wounds, the change in astigmatism after suture removal, and the late apparently spontaneous changes in astigmatism after PKP in some eyes.

Incidence of endophthalmitis after cataract surgery in the Netherlands

In order to investigate the incidence of endophthalmitis following various types of cataract surgery, we sent a questionnaire to the members of the Dutch Intraocular Implant Club (NIOIC). Retrospectively, information was obtained about the number of performed cataract extractions, the techniques used, and the number of patients with postoperative endophthalmitis. To estimate bias by underreporting, we calculated the nationwide incidence of endophthalmitis after cataract surgery in the same period of time. The response rate to the questionnaire was 51.2%. In the reporting group the incidence of endophthalmitis was 0.11%. This incidence was comparable with the calculated nationwide incidence (0.15%). Comparison between the incidences after phacoemulsification (0.10%) and after other techniques (0.16%) showed no significant difference in the questionnaire group. A complicated cataract extraction preceded 12 out of the 38 reported cases with endophthalmitis. In conclusion, the incidence of endophthalmitis after cataract surgery in the Netherlands is comparable with the incidence reported in literature. The occurrence of complications during surgery rather than the technique used affects on the development of endophthalmitis.

Automated video image morphometry of the corneal endothelium

The central corneal endothelium of 13 eyes in 13 subjects was visualized with a non-contact specular microscope. This report describes the computer-assisted morphometric analysis of enhanced digitized images, using a direct input by means of a frame grabber. The output consisted of mean cell area, cell density, frequency distribution of the individual cell area, and cell polygonality. Results showed that the mean coefficient of variation of images analyzed three times consecutively was 0.95 percent. The cell analysis of three different images of the same subject was accurate, with a mean coefficient of variation of 4.2 percent.

Efficacy of ophthalmic solutions to detach adhering Pseudomonas aeruginosa from contact lenses

Purpose To compare the efficacies of two all-in-one contact lens (CL) cleaning solutions and a detergent mixture on the detachment of a pathogenic bacterium adhering to two types of contact lenses in the absence and presence of a tear film. Methods Bacterial-detachment studies were carried out in a parallel-plate flow chamber. Rigid gas permeable (RGP) CLs with and without a tear film were fixed on the bottom plate of the flow chamber. After adhesion of Pseudomonas aeruginosa no. 3, bacterial detachment was stimulated by perfusing the system either with an all-in-one CL-cleaning solution, for soft contact lenses (SCL solution) and for rigid lenses (RCL solution), or with a detergent mixture of 0.25% (wt/vol) sodium lauryl sulfate (SLS) and 0.2% sodium methyl cocoyl taurate (Tauranol). In addition, the all-in-one RCL-cleaning solution supplemented with 0.025% (wt/vol) SLS and 0.02% (wt/vol) Tauranol was evaluated. A surface physical-chemical analysis of the lenses before and after application of the solutions was done to determine whether remnants of the ophthalmic solutions or detergents could be found adsorbed to the CL surfaces. Results Both all-in-one CL-cleaning solutions stimulated minor bacterial detachment from CL surfaces with or without a tear film. The SLS/Tauranol detergent mixture, however, removed ⩽ 95% of the adhering P. aeruginosa cells, whereas the RCL-cleaning solution supplemented with detergents also stimulated significant detachment. Surface physical-chemical analysis clearly demonstrated the presence of a tear film on the CL surfaces, but remnants neither of the ophthalmic solutions nor of the detergents could be found. Conclusion Ophthalmic solutions are not effective in stimulating detachment of adhering bacteria from CL surfaces. Supplementing of an all-in-one CL-cleaning solution with only small amounts of detergents yielded a solution much more effective in stimulating bacterial detachment while leaving no detectable remnants of the ophthalmic solution or of the detergents on the CL surfaces.

Immune electron microscopy and a cultural test in the diagnosis of adenovirus ocular infection.

Immune electron microscopy (IEM) and virus isolation in cell culture were compared in the diagnosis of adenovirus ocular infection during an outbreak of the disease in 1979. Eleven of 14 patients with a keratoconjunctivitis clinically indicative of adenovirus infection had IEM evidence of adenovirus infection or had the virus isolated from ocular swabs. The IEM was positive in 8 patients. Virus as isolated from 10 patients. IEM was positive in one culture negative patient. Since IEM provides a rapid and sensitive method for the detection of adenovirus in human tears, it may be a valuable diagnostic tool for the clinician.

Corneal Graft Survival in HLA-A- and HLA-B-Matched Transplantations in High-Risk Cases with Retrospective Review of HLA-DR Compatibility

&NA; In 107 HLA‐A‐ and HLA‐B‐matched corneal transplantations performed in high‐risk patients, the 3‐year graft survival was 60.5%. The criteria used for the definition of high risk were vascularization of the recipient cornea and/or one or more previous failed grafts; they were also the indications for HLA typing and matching. Donor/recipient compatibility was defined by the presence of only 0 or 1 HLA‐A or HLA‐B mismatches. When nonimmunological factors leading to graft failure were excluded, the 3‐year survival was 76.3%. During that follow‐up period, a total of 33 grafts failed; in 13 cases, the cause was allograft rejection. When only first transplants were considered, a 3‐year graft survival of 81.0% was observed. Retrospective DR typing was possible in 33 cases. Because only three graft rejections occurred in that group, we were unable to assess the importance of DR compatibility on the survival of corneal allografts.