Klaus Schmitz

Laser iridocystotomy for bilateral acute angle-closure glaucoma secondary to iris cysts

PURPOSE To report laser iridocystotomy for bilateral acute angle-closure glaucoma secondary to peripheral iris cysts. METHOD Case report. RESULTS In a 55-year-old man with increased bilateral intraocular pressure, gonioscopy revealed varied angle narrowing. Bilateral angle-closure glaucoma secondary to peripheral iris cysts was diagnosed by ultrasound biomicroscopy. The peripheral iris cysts could not be seen in mydriasis by gonioscopy. Therefore, we decided to perform laser iridocystotomy with argon and Nd:YAG laser. Collapse of the cysts after laser treatment was demonstrated by ultrasound biomicroscopy. At follow-up, 9 months after laser treatment, intraocular pressure had dropped below 20 mm Hg in both eyes without further therapy. The iris cysts did not recur, which was demonstrated by ultrasound biomicroscopy. CONCLUSIONS Peripheral iris cysts may produce angle closure and may cause secondary angle-closure glaucoma. If transpupillary laser cystotomy is not possible, laser iridocystotomy may produce collapse of the iris cysts and correction of secondary angle closure.

Use of internet technologies for data acquisition in large clinical trials.

Data acquisition for automated processing is a central aspect of clinical trials with large numbers of cases because of their extensive demand for manpower. Scientific data can be collected using data forms, which are created in Hypertext Markup Language and published on the Internet. The completed data form can be returned via E-mail or Common Gateway Interface-Script and forwarded into a study database. For the Internet-based data acquisition of a prospective multicenter trial (e.g., on endophthalmitis incidence after cataract extraction), we developed two special HTML forms that can be opened in the ophthalmology departments homepage. A large number of acquired anonymous data has been collected via Internet and automatically transferred into the trial database. The Internet provides a fast and easy avenue for the acquisition of scientific data. This method of data acquisition and data processing will become more common place in multicenter clinical trials.

Inadvertent Scleral Perforation in Eye Muscle versus Retinal Detachment Buckle Surgery

Purpose. Inadvertent scleral perforation is a recognized complication of eye muscle and retinal detachment buckle surgery. If these operations are performed by the same surgeon, it is unknown which of these procedures has a higher risk of scleral perforation. Methods. In the period from 1999 until 2004, 427 eyes of 317 patients were operated using eye muscle surgery and 81 eyes of 80 patients with retinal detachment buckle surgery. All operations were performed by the same surgeon (JK). In a retrospective, single-center, comparative, observational study, the records of these patients were assessed to determine the number of scleral perforations with retinal damage or drainage of subretinal fluid. Results. In the group receiving retinal detachment buckle surgery there were two cases of scleral perforation. In one case, scleral perforation occurred during buckle installation and in the other case during placement of a cerclage. The rate of scleral perforation was 2.5 % per patient and per eye in this group. In the group receiving eye muscle surgery no scleral perforations occurred. Conclusion. The number of scleral perforations was higher in retinal detachment buckle surgery than in eye muscle surgery, with all procedures haveing been performed by the same surgeon.

Bilateral spontaneous corneal perforation associated with complete external ophthalmoplegia in mitochondrial myopathy (Kearns-Sayre syndrome)

PURPOSE Mutations of mitochondrial DNA can lead to a variety of pheno- and genotypically heterogeneous diseases. Kearns-Sayre syndrome is caused by the deletion of several mitochondrial genes. The syndrome is characterized by chronic progressive external ophthalmoplegia, tapetoretinal degeneration, and severe generalized myopathy. CASE REPORT We report on a 36-year-old female patient with Kearns-Sayre syndrome, confirmed by biochemistry, histology, and genetics. Over a period of 10 years, progressive ophthalmoplegia led to recurrent conjunctivitis, keratitis, and corneal ulceration. Almost total external ophthalmoplegia including involvement of the orbicularis oculi muscles was observed. Despite advanced ptosis, there was lagophthalmos of 2 mm with near complete extinction of globe motility in both eyes. The left eye showed a peripheral corneal perforation parallel to the lower limbus. After successful penetrating keratoplasty in the left eye, despite preventive measures, a peripheral corneal perforation also occurred in the right eye. Penetrating keratoplasty was therefore also performed on the right eye. To achieve a satisfactory functional result, large-diameter transplants were necessary in both eyes. To prevent immune reactions, cyclosporine therapy was initiated prophylactically. Sixteen and 9 months after penetrating keratoplasty, the corrected visual acuity was 20/60 in the right eye and 20/100 in the left eye, with clear transplants on both sides. DISCUSSION Patients with progressive ophthalmoplegia require thorough neurologic investigation and evaluation. Lagophthalmos in the presence of almost absent globe motility requires extensive preventive measures to avoid exposure keratitis. In spite of this, in the presented case, corneal perforation of the second eye could not be prevented.

Excimer laser "corneal shaping": a new technique for customized trephination in penetrating keratoplasty

PurposeThe aim of the presented experimental work was to develop a technique for congruent trephination of donor and recipient corneas in free form using a 193-nm excimer laser and to study the clinical follow-up after the application of the technique in a rabbit model.MethodsIn 12 New Zealand White rabbits homologous penetrating keratoplasty was performed. Trephination of donor buttons and recipient beds was achieved in six animals by conventional mechanical trephination and in six by excimer laser trephination with a guided laser beam in a non-circular geometry. The surgical procedure and its applicability to human subjects were evaluated and the postoperative clinical course was followed for 6 months.ResultsThe surgical procedure of full-thickness excimer laser trephination could be performed reproducibly in the animal model both for dissection of the donor buttons and for preparation of the recipient beds. Keratoplasty was performed with kidney-shaped transplants after trephination in free form with the guided laser beam. Postoperative clinical follow-up did not show any differences between the two trephination groups that could be related to the applied trephination technique. After 6 months we observed well-adapted and clear corneal grafts, kidney-shaped in the excimer trephination group and circular in the mechanical trephination group. No side effects on the crystalline lens and the central retina could be clinically observed following excimer laser trephination.ConclusionWe present the first experimental study of keratoplasty with freely selected transplant geometry and perfect congruence of donor button and recipient bed. The application of this technique in certain corneal disorders in humans will offer improved treatment options in the future.