Laser therapy of ocular toxoplasmosis]

The authors present the results of treatment by laser coagulation of inflammatory retino-choroidal foci in 32 persons with ocular toxoplasmosis. The diagnosis of Toxoplasma etiology was set on a basis of positive immunological reaction for Toxoplasma gondii antigen and after exclusion of other etiological factors. Among 42 eyes stabilization of the process after 1 intervention was observed in 34, i.e. in 89 p.c. (period of observation--up to 4 years). In the following 8 eyes arised the necessity to perform additional coagulations because of formation of fresh foci which appeared in 5 eyes after 6 months, in 2 eyes after 1 year and in 1 eye after 2 years since onset. The authors consider the application of laser coagulation in ocular toxoplasmosis as a favourable method together--or independently--with pharmacological treatment.     

Selective occlusion of ocular neovascularization by photodynamic therapy]

Photodynamic therapy (PDT) has successfully been used to induce vascular occlusion via endothelial damage and subsequent thrombosis. To increase the selective of this method for neovascularizations, characteristics in the ultrastructure of the proliferative vessel wall allow physiological vessels to be spared and predominantly neovascularizations to be occluded: (a) Due to the disturbance of the blood-retina barrier, free dye molecules accumulate within the vascular wall. Using a dye with prolonged retention, such as phthalocyanine (CASPc), it is possible to thrombose neovascularizations 24 h post injection while leaving the physiological vasculature of the anterior segment of the rabbit eye unaffected. (b) Proliferating endothelial cells express high numbers of low-density lipoprotein (LDL) receptors. Chlorin e6 (Ce6), a potent photosensitizer, is covalently bound to LDL. Intravascularly, ce6-LDL complexes selectively label neovascular walls. Since ce6-LDL is incorporated intracellular into enzymatically active lysosomes, photothrombosis is effectively achieved at low drug and light doses in vivo. In addition, the induced damage is spatially confined to the inner vascular lining. We conclude that carrier-mediated PDT may offer a new and sensitive approach for selective treatment of intraocular neovascularizations.     

Manifestations of ocular rosacea in females with dark skin types

BackgroundCurrent knowledge about ocular rosacea in dark skin individuals is lacking. The prevalence of ocular rosacea varies considerably among studies and is probably higher than previously presumed.ObjectiveTo estimate the prevalence and pattern of ocular rosacea among dark skinned female patients, compare it with fair skinned, and to correlate the severity of cutaneous disease with ocular findings.MethodFemale patients diagnosed with rosacea between 2011 and 2013 were studied prospectively. They were referred to ophthalmology for clinical observations and slit lamp examination. In all patients Schirmer and Tear break up time tests to diagnose dry eye were performed.ResultFifty six consecutive female patients, joined the study with different skin types ranging from skin type 4 to 6. A total of 43 patients (76.8%) were positive for ophthalmologic findings. The most frequent symptoms were itching, burning sensation and redness, while the most frequent signs were meibomian gland dysfunction, dry eyes, eyelid telangiectasia and irregular margin. Significant correlation was noted between meibomian gland dysfunction and irregular lid margin (P = 0.003). Dry eye and Schirmer test significantly correlated with eye lid telangiectasia (p = 0.004; 0.015) respectively. No significant correlation was found between the severity of cutaneous disease and ocular findings.ConclusionOcular rosacea in dark skinned females is a common presentation and is comparable to that reported for fair skin, with eyelid telangiectasia and meibomian gland dysfunction being early phenomena. Earlier onset and more benign course were seen compared to other studies. Ocular and cutaneous rosacea are independent of each other.     

Trifluorothymidine and idoxuridine therapy of ocular herpes.

In a coded study, we treated 40 patients who had active herpes simplex corneal ulcers with either 1% trifluorothymidine (F3T) or 0.1% idoxuridine (IDU) drops; we treated 15 similarly afflicted patients, who had failed on IDU or vidarabine, with open 1% F3T drops. All dosages were at therapeutically recommended frequency. In the coded study there was no statistically significant difference between the drugs in rate of healing; mean initial ulcer size in both groups was approximately 7 mm2 and mean healing time was approximately 5.5 days. There was a significant difference, however, in the chances of successful healing; 96% of all F3T treated eyes and only 75% of IDU treated eyes healed completely within 14 days. In the open study, 87% of patients healed completely on F3T eyedrops. Although an insufficient number of patients were on concomitant coricosteroid therapy to provide statistical analysis, F3T-corticosteroid treated eyes (eight masked and open) all healed. The one IDU-corticosteroid treated eye in the masked study failed to heal.     

Comparative study of ocular herpes simplex virus in patients with and without self-reported atopy

PURPOSE: To compare the characteristics of ocular herpes simplex virus (HSV) in patients with and without atopy. DESIGN: Retrospective cohort comparative study. METHODS: Patients who presented at the Cornea Service, Wills Eye Hospital, between March 2003 and March 2004 who had been previously diagnosed in the same institution as having ocular HSV diagnosis or were just diagnosed as having the disease were asked to complete a study questionnaire that enabled categorization into atopic and nonatopic. In April 2005, 223 patients who agreed to be in the study had their charts reviewed, and 125 patients were excluded according to exclusion criteria: immunosuppression, follow-up less than one year, previous history of penetrating keratoplasty (PK) out of the Cornea Service, and no active HSV episode during follow-up. MAIN OUTCOME MEASURES: Incidence of all types of HSV recurrences. SECONDARY OUTCOME MEASURES: Bilaterality, visual loss, need for PK , and secondary bacterial infection in both groups. HSV episodes were classified into infectious, inflammatory, and mixed for analysis. RESULTS: Ninety eight patients (110 eyes) were included in the study. Atopic/nonatopic (P value): the mean follow-up was 11.6 (+/- 10.6)/8.8 years (+/- 8.4) (P = .14); the mean incidence of HSV episodes per year of follow-up was: total episodes 0.32 (+/- 0.36)/0.28 (+/- 0.33) (P = .14), infectious 0.16 (+/- 0.22)/0.10 (+/- 0.14) (P < .01), inflammatory 0.11 (+/- 0.19)/0.11 (+/- 0.19) (P < .01), and mixed 0.09 (+/- 0.20)/0.07 (+/- 0.16) (P = .06); bilateral HSV was present in 9/3 patients (P = .22); the mean loss of vision was four lines of Snellen in both groups; PK was performed in 14 of 16 eyes (P = .45); secondary bacterial infection was present in two of four eyes (P = .26). CONCLUSIONS: Atopic patients had considerably more infectious and fewer inflammatory episodes when compared with nonatopics.     

Pharmacologic modulation of vascular permeability in ocular allergy in the rat

Evans blue (EB) dye extravasation has been used as a reliable and objective parameter of the increased vascular permeability of an allergic conjunctivitis experimental rat model that closely mimics human ocular allergy. Five male Wistar rats, previously immunized (Group 1), had DL-dithiothreitol (DTT) applied topically to one eye 15 min prior to topical challenge with egg albumin (EA). The fellow eye (control) received phosphate buffered saline (PBS) 15 min prior to receiving EA. Immediately prior to challenge, the rats were injected intravenously with EB. After 30 min, the animals were killed and the dye extracted from the eyes. The intensity of EB extravasation was determined by spectrophotometry at 620 nm. EB extravasation was significantly higher in the eyes that received DTT than in those that received PBS. Groups 2, 3 and 4 of nonimmunized rats served as additional controls: Group 2 for DTT toxicity, Group 3 as a proof of the reaginic antibody mediation and Group 4 as a control of EB extravasation under normal conditions. Five additional groups of five rats each were immunized and both eyes of each rat received DTT 15 min before EA challenge. One eye of each rat received 0.1% dexamethasone sodium phosphate topically (Group 5), 0.1% pyrilamine maleate (Groups 6 and 7), and 2% disodium cromoglycate (DSCG) (Groups 8 and 9). The fellow eye received the solvent of each drug topically (control). In the eyes treated with antiallergic drugs, EB extravasation decreased 40% for dexamethasone, 44.1% and 10.4% for pyrilamine, and 51.4% and 51.2% for DSCG.