[Multimodal evaluation of the ocular surface using a the new Lacrydiag device]. / Place du NIBUT automatisé dans l'évaluation multimodale de la surface oculaire dans le syndrome sec avec le Lacrydiag.

INTRODUCTION: Dry eye disease is a very frequent condition with a significant impact on patients' quality of life. The most common clinical sign is fluorescein break up time (BUT). Recently, non-invasive measurement of BUT (NIBUT) by Placido disc analysis has been proposed to replace FBUT. We performed an automated NIBUT analysis using Lacrydiag and compared the values obtained with other typical dry eye criteria. METHODS AND MATERIALS: A retrospective study was carried out in the Bicêtre ophthalmology department from July 1 through October 30. Dry eye patients over 18 years of age with Oxford scores>1 and OSDI scores>22 were included. They underwent slit lamp examination to determine fluorescein BUT, Oxford and Arita MGD scores. On the same day, they were tested with the Lacrydiag to assess NIBUT, tear lake height and meibography. OSDI and Schirmer's testing were performed on the date of examination. In this study, only patients' right eyes were included. The correlation between NIBUT and OSDI, Schirmer's testing and tear lake height was analyzed by Pearson's test. The correlation between NIBUT and fluorescein BUT was analysed by both Pearson and Bland-Altman statistical tests. RESULTS: Thirty right eyes (21 women, 9 men) were included. The mean age was 62.3 years (SD 16.0), mean OSDI 49.4 (SD=20.1), mean Oxford score 3.33 (SD 2.1), mean NIBUT 6.91sec (SD 3.4), and mean FBUT 3.6sec (SD 1.8). The NIBUT and FBUT were significantly correlated (R=0.139; P=0.042), with an even more significant concordance (r=0.55; P=0.001) on Bland-Altman graphic analysis, but the mean NIBUT was 2.7 seconds higher than the FBUT (P=0.001 on Bland-Altman analysis). In addition, NIBUT was correlated with the Oxford score (R=0.156; P=0.031), but not with Schirmer I score (R=0.120; P=0.061), OSDI score (R=0.018; P=0.48), tear lake height (R=0.04; P=0.148), or Arita meibomian gland dysfunction score (R=0; P=0.933). CONCLUSION: NIBUT is a possible alternative to FBUT for the measurement of tear film stability, with the advantage of lack of dependence on the amount of fluorescein instilled. In addition, modern imaging methods allow for automated, and thus reproducible, measurement. However, its role in the diagnostic tool kit remains to be precisely defined, especially given its weak correlation with other markers of dry eye and its significant difference from FBUT. The definitive diagnosis of dry eye thus remains based on the combined analysis of signs and symptoms.

[Ocular manifestations of viral diseases]. / Atteintes ophtalmologiques des infections virales.

Viral infections may involve all ocular tissues and may have short and long-term sight-threatening consequences. Among them, ocular infections caused by herpesviruses are the most frequent. HSV-1 keratitis and kerato-uveitis affect approximately are the leading cause of infectious blindness in the Western world, mainly because of corneal opacification caused by recurrences. For this reason, they may warrant long-term antiviral prophylaxis. Herpes zoster ophthalmicus, accounts for 10 to 20% of all shingles locations and can be associated with severe ocular involvement (keratitis, kerato-uveitis) of which a quarter becomes chronic/recurrent. Post herpetic neuralgias in the trigeminal territory can be particularly debilitating. Necrotizing retinitis caused by herpesviruses (HSV, VZV, CMV) are seldom, but must be considered as absolute visual emergencies, requiring urgent intravenous and intravitreal antiviral treatment. Clinical pictures depend on the immune status of the host. Adenovirus are the most frequent cause of infectious conjunctivitis. These most often benign infections are highly contagious and may be complicated by visually disabling corneal lesions that may last over months or years. Some arboviruses may be associated with inflammatory ocular manifestations. Among them, congenital Zika infections may cause macular or optic atrophy. Conjunctivitis is frequent during the acute phase of Ebola virus disease. Up to 15% of survivors present with severe chronic inflammatory ocular conditions caused by viral persistence in uveal tissues. Finally, COVID-19-associated conjunctivitis can precede systemic disease, or even be the unique manifestation of the disease. Utmost caution must be taken because of viral shedding in tears.

[Demodex and ocular surface disease]. / Demodex et pathologies de la surface oculaire.

Demodex is a saprophytic mite of the ocular adnexa, which can in certain circumstances proliferate on the skin of the face and on the eyelid margins. It is involved in facial rosacea (especially in the papulopustular form) and in the development or aggravation of anterior and/or posterior blepharitis or even keratoconjunctivitis, often in association with cutaneous lesions ; the pathophysiology is often multifactorial. Symptoms are non-specific, but the presence of cylindrical sleeves on the eyelashes is very suggestive of infestation, and certain techniques of biomicroscopic examination or imaging, such as confocal microscopy in vivo, allow direct visualization of the parasite. Parasitological examination of the eyelashes can confirm the diagnosis and can be improved by good sampling technique. Eyelid hygiene and oil-based ointments are the cornerstone of treatment. New specific treatments, in particular topical treatments based on tea tree oil, ivermectin, as well as pulsed light therapy and micro-exfoliation of the eyelid margin, can help to reduce the parasitic load and improve symptoms.