[SMILE: Re-Treatment Options - Techniques and Results]. / SMILE: Techniken und Ergebnisse von Nachoperationen.

With a rate of less than 2 %, retreatment after SMILE is rare. If a touch-up is required, there are different options to choose from: surface ablation (PRK/LASEK) with Mitomycin C, the standard femto-flap procedure with the same parameters, the CIRCLE procedure, which extends the previous SMILE interface into a flap, or the innovative but off-label capless SMILE procedure, which preserves all the advantages of SMILE.

[Historical Overview of the Clinical Development of the Small Incision Lenticule Extraction Surgery (SMILE)]. / Die historische Entwicklung der Small-Incision-Lentikel-Extraktions-OP (SMILE).

The clinical use of femtosecond lasers has led to significant progress in the quality of refractive surgery. SMILE femtosecond laser surgery (SMILE: Small Incision Lenticule Extraction) permits the first one step intrastromal laser procedure without a flap. This article describes the gradual development of this surgery during the last ten years.

[Manifestation of bilateral choroidal osteoma in childhood. Progressive myopia due to staphyloma posticum]. / Manifestation eines bilateralen chorioidalen Osteoms im Kindesalter. Progressive Myopie durch Staphyloma posticum.

BACKGROUND: Case report of a 6-year-old boy with bilateral choroidal osteoma. CASE REPORT: The patient was followed up for the next 6 years and during this period bilateral tumor progression was observed. In one eye a staphyloma posticum developed in the area of the osteoma which led to secondary anisometric myopia. CONCLUSION: If undetected, this rare complication can lead to anisometric amblyopia; therefore, repeated cycloplegic refractometry is advisable in children with choroidal osteoma.

[One-year results of small incision lenticule extraction (SMILE) in myopia]. / Ein-Jahres-Ergebnisse bei Small-Incision-Lentikel-Extraktion (SMILE) zur Myopiekorrektur.

BACKGROUND: This clinical trial is focused on the 12-month results of a new method for refractive correction in myopia, called "small incision lenticule extraction" (SMILE). PATIENTS AND METHODS: In a prospective study 91 eyes were treated with the new refractive procedure and the results were published after 6 months. A lenticule of intrastromal corneal tissue is cut utilising the Carl Zeiss Meditec AG (Jena, Germany) VisuMax femtosecond laser system. Thereafter, this lenticule is manually removed without lifting a flap. 55 eyes of 33 patients volunteered for a 12-month follow-up. UCVA and BSCVA after 12 months, objective and manifest refraction as well as slit-lamp examination and late side effects were documented. RESULTS: 55 eyes of 33 patients were re-examined in this study 12 months after surgery. The spherical equivalent before surgery was - 4.66 (± 1.75) D; after 12 months - 0.11 (± 0.42) D was manifest. No significant change was observed compared to the 6-month control. Starting with UCVA of 0.1 (± 0.06) before surgery. UCVA was 1.02 (± 0.3) after 12 months. One eye lost more than two lines. All other patients did not have any late side effects. CONCLUSION: The one-year results of this new procedure are encouraging. Especially stability of the correction of myopia and myopic astigmatism with the SMILE procedure is very good.

[Morphological analysis of corneal refractive lenticules--is there a correlation with refractive results?]. / Ultrastrukturelle Analyse von Hornhautlentikeln nach fs-Lentikelextraktion gibt es einen Zusammenhang mit den refraktiven Ergebnissen?

BACKGROUND: ReLEx®flex is a corneal refractive procedure performed by removing corneal lenticules with a femtosecond (fs) laser system. Using electron microscopy, tissue parameters of extracted lenticules were analysed for potential correlations to the refractive results. Furthermore, the effect of previous contact lens (CL) wear on refractive stability (regression) was tested. PATIENTS AND METHODS: 19 lenticules from 11 patients (age 24-56 years, 8 f, 3 m) were prepared for EM. The central areas of the samples were photographed and the distance between the collagen fibres and their diameters were digitally measured. ANOVA analysis was used to correlate postoperative refractional stability with time of preoperative CL use, fibre diameter and the coefficient of variation (CV) of fibre distance. RESULTS: 14 of 19 lenticules were from patients who had worn CL preoperatively. The cumulative duration of CL wear averaged around 31.2 ± 35.5 thousand hours. Preoperative CL use significantly influenced the postoperative regression: the longer time patients had worn CL, the greater was the regression towards myopia (p = 0.01). Additionally, the morphological parameters collagen fibre diameter (p = 0.09) and CV of fibre distance (p = 0.07) had an impact on regression. CONCLUSIONS: Prolonged CL use and alterations in ultrastructural patterns affected the refractive stability after ReLExflex. Although the pathophysiological relationships between CL use, corneal morphological parameters, and refractive stability are still poorly understood, these findings could potentially be used as prognostic markers for postoperative refraction after ReLExflex.

[Femtosecond lenticule extraction (FLEx) - Results after 12 months in myopic astigmatism]. / Femtosekunden-Lentikel-Extraktion (FLEx) - Ergebnisse nach 12 Monaten bei myopen Astigmatismus.

BACKGROUND: This clinical trial is focussed on the 12-month results of a new method for refractive correction, femtosecond lenticule extraction (FLEx). PATIENTS AND METHODS: In a prospective 6-month study 108 eyes were treated in Erfurt and Marburg. Both a flap and a lenticule of intrastromal corneal tissue were simultaneously cut utilising the Carl Zeiss Meditec AG (Jena, Germany) VisuMax femtosecond laser system. Thereafter, the lenticule was manually removed and the flap repositioned. 31 patients all treated in Erfurt volunteered for a 12-month follow-up. UCVA and BSCVA after 12 months, objective and manifest refraction as well as slit-lamp examination and late side effects were documented. RESULTS: 62 eyes of 31 patients were examined in this study. The spherical equivalent before surgery was -4.81 (± 1.16) D; after 12 months -0.15 (± 0.46) D were manifest. No significant change was observed after the 6 months control. Starting with UCVA of 0.12 (± 0.09) before surgery UCVA was 1.10 (± 0.26) after 12 months. In one patient corneal ectasia was diagnosed. All other patients did not have any late side effects. CONCLUSION: The stability of the correction of myopic astigmatism with the FLEx procedure is very good. The fact that one patient presented with a corneal ectasia demonstrates that one general problem of refractive corneal surgery persists with this new fs technology.

Alteration in goblet cell numbers and mucin gene expression in a mouse model of allergic conjunctivitis.

PURPOSE: To determine whether the number of filled conjunctival goblet cells and mucin gene expression are altered in a mouse model of allergic conjunctivitis. METHODS: A/J mice were sensitized intraperitoneally with cat dander or the peptide P3-1 from the protein Fel d1. Two weeks later, the mice were challenged for 7 consecutive days with eye drops containing the allergens. Conjunctival tissue was harvested at 0, 6, 24, or 48 hours after final antigen challenge. Control samples were naïve animals and mice sensitized with cat dander and challenged with OVA-peptide or PBS. The mean number of filled goblet cells per square millimeter in three forniceal fields for each group was determined in wholemounts of conjunctiva prepared using rhodamine-phalloidin labeling followed by confocal microscopy. RNA was isolated from conjunctiva of the contralateral eye and taken for relative quantitation of mRNA of the goblet cell mucin Muc5AC and the epithelial membrane-spanning mucin Muc4, by real-time RT-PCR. RESULTS: The number of filled goblet cells was significantly decreased with both cat dander and P3-1, after final ocular challenge (P < 0.001). The most significant decrease over naïve mice was seen at 6 hours after final challenge with both allergens. The number of filled goblet cells was still decreased but was returning toward naïve levels at 24 hours (P < 0.05), and at 48 hours no significant difference was seen compared with naïve, PBS-treated, and OVA-peptide-treated control samples. For both cat dander and P3-1, Muc5AC and Muc4 mRNA was found to be decreased at the time of final ocular challenge. The level of Muc5AC mRNA from goblet cells rebounded from the decrease to show an increase over control by 24 hours after final challenge, and by 48 hours, the mRNA level had returned to naïve control range. In contrast, significant increases in Muc5AC mRNA were evident after final control challenge with PBS or OVA-peptide, indicating a potential irritant effect of drop application. The Muc4 mRNA level was significantly reduced at all time points except 24 hours after the last challenge. By comparison with allergen-challenged eyes, no change in Muc4 message levels was noted at any time point in OVA-peptide- or PBS-treated control eyes. CONCLUSIONS: These findings demonstrate that, in the conjunctiva of mice, repetitive application of allergens induces a reduction in the number of filled goblet cells and a decrease in Muc5AC and Muc4 mRNAs. After a period of 24 to 48 hours, the goblet cell number return to naïve levels, and goblet cell mucin mRNA levels return to above or within normal range, indicating a rapid recovery in the mucus secretion system.

Trefoil peptides promote restitution of wounded corneal epithelial cells.

The ocular surface shares many characteristics with mucosal surfaces. In both, healing is regulated by peptide growth factors, cytokines, and extracellular matrix proteins. However, these factors are not sufficient to ensure most rapid healing. Trefoil peptides are abundantly expressed epithelial cell products which exert protective effects and are key regulators of gastrointestinal epithelial restitution, the critical early phase of cell migration after mucosal injury. To assess the role of trefoil peptides in corneal epithelial wound healing, the effects of intestinal trefoil factor (ITF/TFF3) and spasmolytic polypeptide (SP/TFF2) on migration and proliferation of corneal epithelial cells were analyzed. Both ITF and SP enhanced restitution of primary rabbit corneal epithelial cells in vitro. While the restitution-enhancing effects of TGF-alpha and TGF-beta were both inhibited by neutralizing anti-TGF-beta-antibodies, trefoil peptide stimulation of restitution was not. Neither trefoil peptide significantly affected proliferation of primary corneal epithelial cells. ITF but not SP or pS2 mRNA was present in rabbit corneal and conjunctival tissues. In summary, the data indicate an unanticipated role of trefoil peptides in healing of ocular surface and demand rating their functional actions beyond the gastrointestinal tract.

Analysis of topical cyclosporine treatment of patients with dry eye syndrome: effect on conjunctival lymphocytes.

OBJECTIVE: To study the effect of topical cyclosporine on lymphocyte activation within the conjunctiva of patients with moderate to severe dry eye syndrome (Sjögren and non-Sjögren). METHODS: Biopsy specimens were obtained at baseline and after 6 months of cyclosporine treatment from eyes of 32 patients with moderate to severe dry eye syndrome; 19 were cyclosporine treated (0.05% cyclosporine, n = 13; 0.1% cyclosporine, n = 6) and 13 were vehicle treated. Within this group there were 12 with Sjögren syndrome and 20 with non-Sjögren syndrome. Biopsy tissue was analyzed using immunohistochemical localization of binding of monoclonal antibodies to lymphocytic markers CD3, CD4, and CD8 as well as lymphocyte activation markers CD11a and HLA-DR. RESULTS: In cyclosporine-treated eyes, biopsy results of conjunctivae showed decreases in the number of cells positive for CD3, CD4, and CD8, while in vehicle-treated eyes, results showed increases in these markers, although these differences were not statistically significant. Following treatment with 0.05% cyclosporine, there was a significant decrease in the number of cells expressing the lymphocyte activation markers CD11a (P<.05) and HLA-DR (P<.05), indicating less activation of lymphocytes as compared with vehicle treatment. Within the Sjögren patient subgroup, those treated with 0.05% cyclosporine also showed a significant decrease in the number of cells positive for CD11a (P<.001) as well as CD3 (P<.03), indicating a reduction in number of activated lymphocytes. CONCLUSION: Treatment of dry eye syndrome with topical cyclosporine significantly reduced the numbers of activated lymphocytes within the conjunctiva. Arch Ophthalmol. 2000;118:1489-1496

Interleukin-6 levels in tears of contact lens wearers.

The purpose of this study was to evaluate the presence of interleukin-6 (IL-6) in basal tears of contact lens wearers (n = 18) and nonlens wearers (n = 25). Samples (5 microl) were collected with a microcapillary pipette and evaluated using PAGE electrophoresis and immunoblot analysis. Contact lens-wearing patients had a mean IL-6 level of 43.8 +/- 5.3 pg/5 microl compared with nondetectable IL-6 levels throughout the noncontact lens-wearing population. IL-6 in several patients removed from contact lens wear for 6 days became nondetectable. When these patients were returned to wearing lenses, IL-6 levels increased to their original levels within 24 h. The data presented indicate that an ocular medical device may stimulate IL-6 production.

Microglia increase as photoreceptors decrease in the aging avian retina.

PURPOSE: There is evidence that microglial activation occurs with normal aging in some regions of the brain of rodents. We investigated the pattern of microglia in the retinas of young and aged quail and pigeons to determine if age-related retinal changes evoked migration of microglia into the outer retina. In quail we also investigated the correlation between activated microglia and age-related photoreceptor loss. METHODS: Microglia were identified with the monoclonal antibody QH1 in cryosectioned eyes from pigeons, ages 2 to 20 years (n = 14), and in paraffin sections from six-month (n = 15) and one-year-old quail (n = 30). Rounded microglia in the photoreceptor layer were counted in consecutive 400x fields from temporal to nasal. Photoreceptor counts were made from 10 quail retina flat mounts. The photoreceptor number was compared to the number of microglia in corresponding regions of the same retina. RESULTS: Rounded microglia were detected among the photoreceptors of pigeons and quail. Significantly more of these microglia were found in peripheral than in central regions close to the pecten (pigeon p < 0.002 and quail p < 0.01). Furthermore, more microglial cells were present among peripheral photoreceptors of older quail (p < 0.03) and pigeons (p < 0.05) than in the younger birds. In the peripheral retina of the older quail, microglia were significantly and inversely related to the number of photoreceptors (r2 = 0.9; p < 0.001). CONCLUSIONS: Increased microglial were observed in the peripheral retina of both old quail and old pigeons. In the quail, the rounded (activated) microglia were distributed preferentially in regions of greatest photoreceptor loss. Microglial activation does not appear to be a general phenomenon of the aging retina, but in quail activation appears directly related to photoreceptor loss. It is unclear at this time how the change in microglia shape and distribution is related to their neuroprotective / neurotoxic potential.