Effect of prostaglandin analogues on the biomechanical corneal properties in patients with open-angle glaucoma and ocular hypertension measured with dynamic scheimpflug analyzer.

PURPOSE: The aim of the study is to evaluate the effect of topical prostaglandin (PG) treatment on the corneal biomechanical properties in treatment-naïve patients with either primary open-angle glaucoma (POAG) or ocular hypertension (OHT) using the Corvis ST device. METHODS: This is an observational study. We analyzed the Corvis ST dynamic corneal response parameters of our database using the newest software available. Thirty-four eyes of 34 patients were included. They were all newly diagnosed and treatment-naïve. Patients were evaluated at baseline and after 6 months of treatment with prostaglandin analogues. Ultrasound pachymetry, Optical Coherence Tomography (OCT) and a 24-2 visual field test were performed in baseline visit. Goldman Applanation Tonometry (GAT-IOP) and Corvis ST dynamic corneal response parameters were registered at baseline and at the 6-month visit. RESULTS: After 6 months of treatment, the IOP decrease (Δ) values obtained with the different tonometers were ΔGAT -6.5 ± 3.7, ΔIOPnct -4.4 ± 5.7 and ΔbIOP -3.8 ± 5.4. The differences between ΔGAT vs ΔIOPnct, ΔGAT vs ΔbIOP, and ΔIOPnct vs ΔbIOP, were statistically significant (p < 0.05 for all comparisons). Statistically significant lower values of the stress-strain index (SSI) (1.77 ± 0.3 at baseline vs 1.54 ± 0.27 at the 6-month visit) were found (p = 0.0002). CONCLUSION: The SSI provided by the Corvis ST seems to decrease significantly after topical prostaglandin therapy. We believe that our results support the hypothesis that topical PG therapy does decrease the corneal stiffness and thus, that the ocular hypotensive effect of these drugs is overestimated if GAT is used for IOP measurement.

Charles Bonnet syndrome as first manifestation of occipital infarction.

PURPOSE: To describe a case of Charles Bonnet syndrome as the first manifestation of occipital infarction in a patient with preserved visual acuity. OBSERVATIONS: We report a 78-year-old man followed in our department with a two-month-long history of visual hallucinations based on the vision of flowers and fruits intermittently, being perceived as unreal images. Best-corrected visual acuity was stable in the follow-up time being 20/20 in the right eye and 20/25 in the left eye. Extraocular muscle function testing, pupillary reflexes, biomicroscopy, fundus and optical coherence tomography examinations did not reveal any interesting findings. In order to rule out occipital pathology, orbital-cerebral magnetic resonance imaging was performed, showing an image compatible with the chronic ischemic right occipital lesion. The patient was diagnosed with Charles Bonnet syndrome secondary to occipital infarction and neurology decided that no treatment was required. 24-2 and 10-2 visual field tests showed no remarkable alterations and Full-field 120 point screening test showed nonspecific peripheral defects. Hallucinations improved over the months, being described as not annoying and increasingly infrequent. CONCLUSIONS AND IMPORTANCE: Charles Bonnet syndrome is a condition characterized by the presence of recurrent and complex visual hallucinations in patients with visual pathway pathologic defects. Visual acuity or visual field loss is not a requirement for diagnosis. Charles Bonnet syndrome should be suspected in all patients with non-disturbing visual hallucinations, even though they present good visual acuteness. It will be essential to perform complementary explorations to identify the underlying pathology that allows the starting of a correct treatment option.

Ocular thelaziosis: A case report of an emerging zoonosis.

PURPOSE: To describe an unusual case of ocular thelaziosis due to Thelazia callipaeda, an underdiagnosed and emerging zoonosis. OBSERVATIONS: We report an 81-year-old woman presented to our emergency department with a week long history of bilateral redness and tearing that had not improved despite antibiotics and corticosteroid topical treatment. Slit-lamp biomicroscopy showed signs of bilateral conjunctivitis and mucopurulent discharge in fornices. Under the upper tarsal conjunctiva of the left eye, two filiform worms were identified, which were removed and sent on wet mount slides for microscopic examination and genetic identification. The rest of the ophthalmoscopic examination was rigorously normal. Polymerase chain reaction (PCR) assay turned positive for Thelazia callipaeda. During further questioning, the patient reported that she had been on summer vacation in contact with dogs which were infected with eye worms. CONCLUSIONS AND IMPORTANCE: Ocular thelaziosis is an emerging zoonosis in Spain, but also in the rest of the world. Ophthalmologists should include ocular thelaziosis in humans as a possible cause of conjunctivitis, tearing, and corneal ulcer, thus avoiding underdiagnosis and inappropriate treatments. The epidemiology of the disease makes anamnesis essential. A confocal biomicroscopy is a useful device for identifying this eyeworm but the definitive diagnosis will be made taking into account the morphological identification under microscope, together with the molecular identification by PCR techniques.