Felicia Ferreri

Sodium hyaluronate eye drops of different osmolarity for the treatment of dry eye in Sjögren's syndrome patients

Aim: To study the effect of the treatment of dry eye in Sjögrens syndrome patients with hypotonic or isotonic hyaluronate eye drops. Methods: 40 Sjögrens syndrome patients were divided in two groups and treated as follows: group 1 with hypotonic (150 mOsm/l) 0.4% hyaluronate eye drops; group 2 with isotonic 0.4% hyaluronate eye drops. The eye drops were instilled six times a day for 90 days. Grading of subjective symptoms, break up time (BUT), corneal fluorescein staining, conjunctival rose bengal staining, Schirmers I test, and conjunctival impression cytology were carried out at 0 and 15, 30, 90 days from the beginning of the study. Patients were examined in a blind fashion. For the statistical analysis the Students t test, Mann-Whitney U test, and χ2 test were performed. Results: Symptoms were statistically significantly improved at day 15 in both groups but group 1 patients had a global score statistically significantly better group 2 (p=0.02). At day 15 group 1 patients had an improvement from baseline values of BUT (p=0.003), fluorescein, and rose bengal score (p=0.000001 and p=0.0004 respectively). Group 2 patients had, at day 15, an improvement of BUT and fluorescein score compared to baseline values (p=0.05 and p=0.0001 respectively). A comparison between the two groups showed better results for group 1 patients at day 15 for rose bengal stain (p=0.01) and for BUT (p=0.05) and fluorescein score (p=0.0003) at day 90. The conjunctival impression cytology showed that group 1 had a statistically significant better total score than group 2 starting from day 15 and lasting throughout the study (p<0.02). Also group 2 patients showed an improvement from baseline values starting from day 30 (p=0.000005). Conclusion: Hyaluronate eye drops are useful for treating severe dry eye in Sjögrens syndrome patients. The use of a formulation with pronounced hypotonicity showed better effects on corneoconjunctival epithelium than the isotonic solution.

Age-related modifications of corneal sensitivity.

Purpose: To evaluate central and peripheral corneal sensitivity (CS) in relation to age. Methods: Five hundred eyes of 320 healthy subjects (185 males and 135 females) were examined. The age of participants ranged from 20 to 90 years. All subjects were divided into 3 groups according to age. CS was assessed with the Cochet-Bonnet esthesiometer in the central cornea and in 8 peripheral points. The averages were used as the values of central and peripheral CS. Results: In the young population, CS was equal in both examined zones (p > 0.05); although, with respect to the periphery after the fifth decade, it was significantly higher in the centre (p < 0.05). Both central and peripheral sensitivity decreased with age (p < 0.05), and such variations are represented by parabolic curves. No differences were observed between males and females. Conclusions: The age-related decrement of CS involves at first the corneal periphery and successively spreads toward the central zone. Topographical distribution and age-related modifications should be considered in clinical investigations of CS, especially in patients who underwent any corneal surgical procedure.

Ocular Surface Changes in Type 1 Diabetic Patients

Patients suffering from insulin-dependent type 1 diabetes mellitus often complain of eye discomfort and have a higher glucose content in tears than control subjects of the same age and sex.1,2 In addition, the glucose content is not correlated with glycemia and HbA1C but is inversely correlated with the break-up time for corneal tear film (BUT). Presumably, the increase in glucose could in some way alter the balance between the various components of tear film, thus reducing its stability.

Postural Modifications of the Oscillatory Potentials of the Electroretinogram in Primary Open-Angle Glaucoma

The postural variations in the retinal microcirculation in glaucomatous patients were studied by evaluation of the oscillatory potentials (OPs) of the ERG. The OPs in scotopic adaptation were examined in subjects with primary open-angle glaucoma and in an age- and sex-matched normal control group in different body positions (seated, supine, anti-Trendelenburg, Trendelenburg). In the seated position, the difference of mean OP amplitude between the control group and the glaucomatous patients was highly significant (p < 0.001). In the normal subjects the OP amplitude in the Trendelenburg position was statistically lower with respect to the values obtained in all other positions (p < 0.05). In the glaucomatous patient group, the OP amplitude in the anti-Trendelenburg position was increased as compared to the other positions (p < 0.05). The study showed a reduction in amplitude of OPs in glaucomatous patients and their different behaviour in both groups with changes in body position.

Effects of Tear Substitutes on Conjunctival Epithelium of Mice

Aim: The effects of the administration of three tear substitutes on normal conjunctival epithelium of the mouse, with particular regard to goblet cells, were studied. Methods: Three-month-old Swiss CD 1 mice were divided into four groups of 7 animals each. Group 1 was untreated (control). The other animals were treated with the instillation of 5 drops/day for 10 days as follows: group 2, 0.2% sodium hyaluronate (SH); group 3, 0.5% hydroxypropylmethylcellulose (HPMC); group 4, 0.9% NaCl. The entire conjunctiva was processed for light and electron microscopy. A morphometric study was performed to evaluate: the number and size of goblet cells and the number, size and optical density of mucin granules. Furthermore, Alcian blue/periodic acid-Schiff (AB/PAS) staining for goblet cells was carried out. Results: The SH-treated group showed that the area and number of goblet cells were similar to the untreated group; the mucin granules were reduced in number and optical density but increased in size. The HPMC-treated group showed a reduced area of goblet cells with reduced optical density of mucin granules. The saline-treated group showed that goblet cells were reduced in area and number; mucin granules showed a reduction in number and optical density and an increased size. The AB/PAS stain showed that each treatment was able to induce a treatment-specific modification of the staining characteristics of goblet cells. Conclusion: Our results strongly suggest that tear substitutes can induce treatment-specific modifications of the conjunctival epithelium with particular regard to goblet cell structure and ultrastructure.

Book Review · Livre nouveau · Buchbesprechung

This book deals with animal studies on corneal graft rejection. The introduction presents the current state of knowledge of allograft reaction after experimental keratoplasty and focuses on immunomodulated therapy with encapsulated monoclonal antibodies (mAb) in local application. In the second chapter, the goals and reasons for a study on the prevention of allograft rejection by local treatment with mAb are given in the form of four questions: (1) can locally applied CD4 mAb affect graft reaction after penetrating keratoplasty? (2) are liposome-incorporated CD4 mAb more effective? (3) do locally applied CD4 mAb have a systemic effect? (4) does the recipient react systemically against graft antigens and are in vitro tests meaningful for clinical grafts? Materials, methods and results are clearly described in the third and fourth chapters. In an experimental model of penetrating keratoplasty in rat eyes, anti-CD4 mAb were injected subconjunctivally or applied as drops in two different forms of administration selected for free mAb in a first test series and liposome-encapsulated mAb in a second. The results of liposome-encapsulated mAb application showed a declining incidence of immunologic graft reactions after subconjunctival injection and also after drop application. The controls showed no effects. A systemic effect on CD4+ lymphocytes could be excluded by flow cytometry. The cytotoxic T lymphocyte activity tested by antigen-specific cytotoxic T lymphocyte in vitro tests was significantly elevated after allograft reactions as an indication of specific sensitization. In contrast to this, no delayed-type hypersensitivity response was observed in the present study. These results are discussed in detail in the fifth chapter. In summary, the results described in this book open up new perspectives for preventing allograft reactions after keratoplasty by local application of liposome-encapsulated specific mAb. These exciting animal results should proceed to clinical trials in the near future.

Effect of intraocular acetylcholine and carbachol on the corneal endothelium. In vivo comparative study.

The purpose of this study is to evaluate differences in corneal endothelial cell loss after intraocular use of two different miotics in subjects who have undergone extracapsular cataract extraction with posterior chamber intraocular lens implantation. The patients were divided into two groups: the first received 1 ml of 1% acetylcholine chloride and the scond 0.5 ml of 0.01% carbachol as intraocular miotics. The endothelial count was done preoperatively and then 1 month after cataract extraction. There were no statistically significant differences in the mean cell loss between both groups. The authors believe that both miotics could be used in cataract surgery.