Ocular surface and glaucoma, a mutual relationship. Practical suggestions for classification and management.

The chronic use of glaucoma medications could improve the development of an ocular comorbidity, the glaucoma therapy-related ocular surface disease. This could be related to the exposure of the conjunctiva to preservatives, but also active compounds such as prostaglandin analogues may improve the risk of ocular surface inflammation. Inflammation has a negative impact on tolerability and adherence to eyedrops and to the outcome of filtration surgery as well. A stratification of glaucoma patients based not only on visual field progression but also on glaucoma therapy-related ocular surface disease would be desirable for a strategic management. Early diagnosis, individualized treatment, and safe surgical management should be the hallmarks of glaucoma treatment. One of the main issues for the proper and successful management of patients is the right timing, effectiveness and safety for both medical and surgical treatment options leading to a precision medicine in glaucoma disease as the best modern treatment.

Ocular surface in posterior segment surgery.

Nowadays, the technological breakthroughs of mini-invasive vitreo-retinal surgery improved the perioperative management and the outcomes of millions of patients. The most common procedures include pars plana vitrectomy, episcleral surgery, intravitreal injections, and laser photocoagulation. Potential sight and non-sight-threatening side effects have been reported during the follow-up period. Ocular surface disbalance can be induced by the aforementioned procedures, resulting in mild to severe ocular discomfort symptoms. This condition may recognize different causes such as pre-existing or concomitant diseases of the external eye, the surgical procedure damage of the anatomical or physiological structures of the ocular surface, the prolonged side effects induced by the chronic topical treatment that may be toxic to the external eye.In addition to the most frequent dry eye-related signs and symptoms, subconjunctival haemorrhages, corneal epithelium damage, partial loss of corneal sensitivity or changes in corneal nerve density could postoperatively affect our patients.In conclusion, any surgical trauma directed to the posterior segment of the eye may cause the loss of the ocular surface homeostasis. Ophthalmologists should not only recognise and treat, but possibly prevent, all patients' symptoms that could manifest in the postoperative time.

Can artificial tears prevent Acanthamoeba keratitis? An in vitro approach.

BACKGROUND: The use of contact lenses has increased in recent years as has the incidence of Dry Eye Syndrome, partly due to their use. Artificial tears are the most common treatment option. Since these changes can facilitate Acanthamoeba infection, the present study has been designed to evaluate the effect of three artificial tears treatments in the viability of Acanthamoeba genotype T4 trophozoites. Optava Fusion™, Oculotect®, and Artelac® Splash were selected due to their formulation. METHODS: Viability was assessed using two staining methods, Trypan Blue stain and CTC stain at different time intervals (2, 4, 6, 8 and 24 h). Trypan Blue viability was obtained by manual count with light microscopy while the CTC stain was determined using flow cytometry. RESULTS: Trypan Blue staining results demonstrated a decrease in viability for Optava Fusion™ and Artelac® Splash during the first 4 h of incubation. After, this effect seems to lose strength. In the case of Oculotect®, complete cell death was observed after 2 h. Using flow cytometry analysis, Optava Fusion™ and Oculotect® exhibited the same effect observed with Trypan Blue staining. However, Artelac® Splash revealed decreasing cell respiratory activity after four hours, with no damage to the cell membrane. CONCLUSIONS: The present study uses, for the first time, CTC stain analyzed by flow cytometry to establish Acanthamoeba viability demonstrating its usefulness and complementarity with the traditional stain, Trypan Blue. Artelac® Splash, with no preservatives, and Optava Fusion TM, with Purite®, have not shown any useful amoebicidal activity. On the contrary, promising results presented by Ocultect®, with BAK, open up a new possibility for Acanthamoeba keratitis prophylaxis and treatment although in vivo studies should be carried out.

Treatment of Acanthamoeba neurotrophic corneal ulcer with topical matrix therapy.

BACKGROUND: This study was done to evaluate the visual and anatomical outcomes of topical regenerating agents as a novel therapy for neutrophic corneal ulcer (NCU) secondary to acanthamoeba infection. FINDINGS: A 20-year-old woman with a history of contact lens wear was referred to our hospital for keratitis after responding poorly to conventional treatment. In vivo confocal microscopy images suggested acanthamoeba keratitis with double-walled cysts in the anterior corneal stroma. Acanthamoeba infection was confirmed by laboratory findings. She was started on 0.1 % propamidine and 0.02 % chlorhexidine drops every hour. The antibiotic and antifungal drops were stopped when bacterial and fungal cultures proved negative. A central neurotrophic corneal ulcers (NCU) appeared, and despite treatment with artificial tears, bandage contact lens, and autologous serum, the ulcer worsened and she was treated with topical CACICOL20 (1 drop every 2 days) for 8 weeks. The corneal defect was completely repaired in 3 weeks. The treatment was well tolerated, and no local or systemic side effects were noted. Visual acuity remained 20/400. Two months later, the defect was still closed and the patient continued with 0.1 % propamidine and 0.02 % chlorhexidine drops, bandage contact lens, artificial tears, and autologous serum. CONCLUSIONS: Topical regenerating agents interact with components of the extracellular matrix, binding matrix proteins and protecting them from proteolysis, restoring the matrix environment, and improving tissue healing. In this case, CALCICOL20 was effective for vision stabilization, wound healing, and was well tolerated for NCU secondary to acanthamoeba infection.

Ultrasound biomicroscopy examination of posterior chamber phakic intraocular lens position.

OBJECTIVE: To better elucidate the in vivo position of the Collamer posterior chamber phakic intraocular lens (PCPIOL) and its relationship to the iris and the crystalline lens and to analyze possible variations over time. DESIGN: Prospective observational case series. PARTICIPANTS: Eighteen eyes of nine patients were included. INTERVENTION: A Staar Collamer implantable PCPIOL was implanted for the correction of high myopia. MAIN OUTCOME MEASURES: The eyes were studied with a 50-MHz ultrasound biomicroscopy UBM 840. The exact PCPIOL position and the distances between it and the crystalline lens were measured at 3, 6, and 12 months after surgery. RESULTS: There were no intraoperative complications. In 13 eyes (72.22%), contact between the PCPIOL and the crystalline lens was found at some time during follow-up. In 3 eyes (16.6%), central contact could be demonstrated. We also observed that the contact zone and its extension can vary over time. In 2 eyes, rotation of the lens was observed. CONCLUSIONS: We found contact between the PCPIOL and the crystalline lens in a high percentage of cases. There was also mobility of the lens in the posterior chamber, especially in the anteroposterior plane, and, as a consequence, both the contact zone and its extension would vary over time.

Treatment of recurrent corneal erosions using autologous serum.

PURPOSE: To study the effect of autologous serum in the treatment of recurrent corneal erosions. METHODS: Eleven eyes of 11 consecutive patients with acute macroform corneal erosions who had suffered several relapses despite receiving different types of treatment were analyzed from November 2000 to February 2002. All patients were treated with autologous serum for 3 months. RESULTS: Mean follow-up time was 9.4 +/- 3.7 months (range, 4-16). No side effects were noted in any of the treated patients. Treatments prior to the use of autologous serum had failed to avoid recurrences in all the patients, with the mean recurrence rate being 2.2 recurrences per month of follow-up. After the onset of serum treatment, only a single recurrence was recorded in three of the patients (0.028 recurrences per month of follow-up). CONCLUSION: The use of autologous serum for the treatment of patients with recurrent corneal erosion is effective and safe in reducing the number of recurrences experienced by patients.