Extensive Contact Lens Wear Modulates Expression of miRNA-320 and miRNA-423-5p in the Human Corneal Epithelium: Possible Biomarkers of Corneal Health and Environmental Impact.

The identification of new biomarkers of ocular diseases is nowadays of outmost importance both for early diagnosis and treatment. Epigenetics is a rapidly growing emerging area of research and its involvement in the pathophysiology of ocular disease and regulatory mechanisms is of undisputable importance for diagnostic purposes. Environmental changes may impact the ocular surface, and the knowledge of induced epigenetic changes might help to elucidate the mechanisms of ocular surface disorders. In this pilot study, we investigated the impact of extensive contact lens (CL) wearing on human corneal epithelium epigenetics. We performed ex vivo analysis of the expression of the miR-320 and miR-423-5p involved in the processes of cellular apoptosis and chronic inflammation. The human corneal epithelium was harvested from healthy patients before the photorefractive keratectomy (PRK). The patients were divided into two age- and sex-matched groups accordingly to CL wearing history with no CL wearers used as a control. The epithelium was stored frozen in dry ice at -80 °C and forwarded for miRNA extraction; afterwards, miRNA levels were detected using real-time PCR. Both miRNAs were highly expressed in CL wearers (p < 0.001), suggesting epigenetic modifications occurring in chronic ocular surface stress. These preliminary results show the relationships between selected miRNA expression and the chronic ocular surface stress associated with extensive CL use. MicroRNAs might be considered as biomarkers for the diagnosis of ocular surface conditions and the impact of environmental factors on ocular surface epigenetic. Furthermore, they might be considered as new therapeutic targets in ocular surface diseases.

Phacoemulsification Wound Burn and Its Management.

Introduction: The production of ultrasonic energy during phacoemulsification is associated with heat generation that could damage ocular tissues, particularly at the corneoscleral wound site. Case Presentation: This study presents an 89-year-old patient with senile hypermature cataract and Fuchs endothelial dystrophy developing severe thermal corneoscleral injury during phacoemulsification. At presentation, visual acuity was finger count at 40 cm and there was a 1 × 2-mm area of corneal melting at the corneal tunnel with diffuse corneal oedema. After 1 month, a temporal circular corneal patch graft was applied to the corneal burn. A penetrating keratoplasty was performed 16 months after the first surgery. Conclusion: Corneal surgery, including lamellar patch grafts and full-thickness penetrating grafts, could be used, when necessary, to restore the cornea's integrity. These procedures could eliminate corneal scarring, decrease astigmatism, and improve vision in patients with phacoemulsification burns.

Corneal epithelial changes in a patient treated with belantamab mafodotin.

The aim of the study is to report a case of corneal epithelial changes in a patient with refractory multiple myeloma (MM) who was treated with belantamab mafodotin (BM). A 55-year-old man diagnosed with refractory MM was referred to our hospital for treatment with BM, an antibody-drug conjugate targeting B-cell maturation antigen. After 33 days of treatment, the patient experienced a bilateral reduction in visual acuity (VA), along with dry eye symptoms such as itchy eyes and a sensation of having a foreign body. Slit-lamp examination revealed the presence of diffuse microcystic epithelial changes throughout the cornea. BM treatment was discontinued by the oncologist. Sixty days after stopping belantamab, VA gradually improved and the microcystic epithelial alterations progressively diminished. Ninety days after discontinuation of therapy, only a few microcystic epithelial alterations remained, and the patient had 20/20 VA in both eyes. While BM is an effective therapy for refractory MM, corneal epithelial changes are among the most common side effects of this treatment. Close collaboration between ophthalmologists and oncologists is crucial for assessing ocular adverse effects and tailoring treatment accordingly.

One-Year Results of Photorefractive Keratectomy for Myopia and Compound Myopic Astigmatism with 210 nm Wavelength All Solid-State Laser for Refractive Surgery.

BACKGROUND: To examine the 12-month clinical and refractive outcomes of PRK performed with a UV all-solid-state laser. METHODS: The study included healthy patients with myopia and/or compound myopic astigmatism enrolled for refractive surgery and treated with PRK using a 210 nm wavelength, 2 kHz repetition rate, UV all-solid-state laser (LaserSoft, Katana Technologies GmbH, Kleinmachnow, Germany). All subjects were examined at baseline and after 1, 3, 6, and 12 months after the treatment with a slit lamp, refraction, visual acuity assessment (logMAR chart), tonometry, ophthalmoscopy, and corneal tomography with a Scheimpflug camera. The outcome measures considered were uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, central corneal thickness, and transparency. The efficacy, safety, predictability, and stability were determined. RESULTS: The study included 34 eyes of 19 patients. The mean UDVA changed from 1.20 ± 0.43 to -0.05 ± 0.10 logMAR at 12 months, and the mean CDVA changed from -0.03 ± 0.06 to -0.06 ± 0.09 logMAR, respectively. The mean spherical equivalent (SE) changed from -4.90 ± 2.12 D to -0.01 ± 0.40 D and was within ±0.50 D of the intended correction in 91% of eyes and within ±1.00 D in 97% of eyes at 12 months. No eyes lost lines of visual acuity, and 64% of eyes gained one or more lines. CONCLUSIONS: PRK with the 210 nm wavelength, 2 kHz repetition rate, all-solid-state laser LaserSoft system proved to have good visual, refractive, and clinical outcomes after the follow-up at 12 months. The emerging gas-free, solid-state technology might be considered a valid alternative for the gas operating lasers for corneal refractive surgery.

Bilateral Implantation of Multifocal Intraocular Lenses: 10-Year Follow-Up.

PURPOSE: To evaluate and compare the long-term results after bilateral implantation of different multifocal intraocular lenses (MIOLs). METHODS: This retrospective comparative study included 42 patients who underwent cataract surgery with bilateral MIOL implantation. Patients were divided into 5 groups: Group 1 received a refractive ReZoom NGX1 IOL (AMO), Group 2 a diffractive Acrysof ReSTOR SA60D3 IOL (Alcon), and Group 3 a diffractive Tecnis ZM900 IOL (AMO). Group 4 and Group 5 were implanted using the mix and match approach with refractive ReZoom-diffractive ReSTOR IOL and refractive ReZoom-diffractive Tecnis ZM900 IOL, respectively. Primary outcome measures were distance, near, and intermediate distance visual acuity measured 6 months (T0) and 10 years (T1) after surgery. Secondary outcomes were defocus curves, contrast sensitivity, patients' satisfaction, and spectacle independence. RESULTS: All patients achieved best-corrected distance visual acuity (BCDVA) greater than 0.11 logMAR and uncorrected distance visual acuity (UCDVA) greater than 0.14 logMAR at both time points. A decrease in contrast sensitivity was evident, particularly at high spatial frequencies; at T1, Group 4 reported statistically higher values than Group 2 at 12 cycles/degree and 18 cycles/degree and statistically higher values than Group 3 at 18 cycles/degree. Great overall satisfaction was reported even in the presence of dysphotopsia. Tecnis ZM900 IOL showed the lowest incidence of posterior capsular opacification. CONCLUSION: MIOLs could provide adequate functional vision and patient satisfaction, despite the incidence of side effects, in carefully selected patients desiring spectacle independence.

Changes in Anterior Segment Morphology and Intraocular Pressure after Cataract Surgery in Non-glaucomatous Eyes.

BACKGROUND: It is known that cataract extraction is associated with a significant reduction in intraocular pressure, especially in narrow angled eyes; however, the modifications of anterior segment parameters associated with this phenomenon have still not been completely defined. The purpose of this study was to evaluate changes in anterior segment anatomy and intraocular pressure after cataract surgery in non-glaucomatous eyes. METHODS AND MATERIAL: This retrospective case series study included 64 eyes of 64 consecutive patients who underwent phacoemulsification with intraocular lens implantation. Anterior segment parameters and intraocular pressure were assessed and compared before and 6 months after surgery. Anterior segment imaging was performed using Casia SS-1000 anterior segment optical coherence tomography (Tomey, Nagoya, Japan). Anterior segment measurements included anterior chamber depth, anterior chamber width, anterior chamber volume, angle opening distance at 500 µm anterior to the scleral spur, angle recess area 750 µm from the scleral spur, lens vault, trabecular iris space area at 500 µm from the scleral spur, and trabecular iris angle at 500 µm from the scleral spur. Intraocular pressure was measured using the Goldmann applanation tonometer (Model AT 900 C/M, Haag-Streit, Bern, Switzerland). Anterior segment parameters and the relationship of changes in intraocular pressure were also evaluated. RESULTS: All anterior segment parameters increased significantly after surgery (p < 0.05). Both angle opening distance at 500 µm anterior to the scleral spur and anterior chamber depth changes were positively correlated with the preoperative lens vault. The mean intraocular pressure significantly decreased from 14.91 mmHg (± 2.8 SD) to 12.91 mmHg (± 3.13 SD) (p < 0.001). Changes in intraocular pressure correlated negatively with values for the width of the preoperative anterior chamber (r = - 0.533; p = 0.001). CONCLUSION: Cataract surgery led to significant widening of the anterior chamber angle and lowering of intraocular pressure. Further investigations are needed to better understand whether anterior chamber width may be a new independent predictive factor for reduction in postoperative intraocular pressure.

Corneal Sub-Basal Nerve Plexus in Non-Diabetic Small Fiber Polyneuropathies and the Diagnostic Role of In Vivo Corneal Confocal Microscopy.

In vivo corneal confocal microscopy (IVCM) allows the immediate analysis of the corneal nerve quantity and morphology. This method became, an indispensable tool for the tropism examination, as it evaluates the small fiber plexus in the cornea. The IVCM provides us with direct information on the health of the sub-basal nerve plexus and indirectly on the peripheral nerve status. It is an important tool used to investigate peripheral polyneuropathies. Small-fiber neuropathy (SFN) is a group of neurological disorders characterized by neuropathic pain symptoms and autonomic complaints due to the selective involvement of thinly myelinated Aδ-fibers and unmyelinated C-fibers. Accurate diagnosis of SFN is important as it provides a basis for etiological work-up and treatment decisions. The diagnosis of SFN is sometimes challenging as the clinical picture can be difficult to interpret and standard electromyography is normal. In cases of suspected SFN, measurement of intraepidermal nerve fiber density through a skin biopsy and/or analysis of quantitative sensory testing can enable diagnosis. The purpose of the present review is to summarize the current knowledge about corneal nerves in different SFN. Specifically, we explore the correlation between nerve density and morphology and type of SFN, disease duration, and follow-up. We will discuss the relationship between cataracts and refractive surgery and iatrogenic dry eye disease. Furthermore, these new paradigms in SFN present an opportunity for neurologists and clinical specialists in the diagnosis and monitoring the peripheral small fiber polyneuropathies.

Clinical Efficacy, Tolerability and Safety of a New Multiple-Action Eyedrop in Subjects with Moderate to Severe Dry Eye.

Background: To assess the clinical efficacy, tolerability and safety of a new-generation ophthalmic solution containing cross-linked hyaluronic acid 0.15% trehalose 3%, liposomes 1% and sterylamine 0.25% (Trimix® Off Health Italia, Firenze, Italy) (CXHAL) versus trehalose 3% (Thealoz®, Thea Pharmaceuticals, Clermont-Ferrand, France) (TRS) in subjects with moderate to severe dry eye disease (DED). Patients and methods: In this prospective, observational cohort study, 41 subjects with moderate to severe dry eye were enrolled and divided into two age- and sex-matched groups. Group 1 was treated with CXHA eye drops, and group 2 was treated with TRS eye drops four times daily for 2 months. All subjects were evaluated at baseline (V0) and at day 60 ± 3 (V1). The examination comprised Best Corrected Visual Acuity (BCVA) and Symptom Assessment in Dry Eye (SANDE). Tear osmolarity was evaluated using the TearLab Osmolarity System®; Keratograph 5M (Oculus, Wetzlar, Germany) was performed to assess tear meniscus height (TMH), fluorescein tear break-up time (TBUT) and corneal and conjunctival fluorescein staining and meibography; furthermore, slit lamp evaluation was performed for eyelid erythema and edema, conjunctival chemosis and hyperemia and Meibomian gland secretion quality. Results: All patients completed the treatment. BCVA remained stable in both groups, and no adverse events were reported. After 2 months, both groups showed statistically significant improvements for SANDE (p = 0.001 and p = 0.012, respectively), TBUT values (p < 0.001 and p < 0.001, respectively) and staining (p = 0.004 and p = 0.001, respectively) as compared to baseline values. Group 1 showed a statistically significant improvement in SANDE frequency and tear osmolarity (p = 0.02 and p = 0.001, respectively), whereas chemosis was significantly reduced in group 2. The amount of TBUT improvement was statistically higher in group 1 compared to that in group 2 (p = 0.041). Conclusion: A new-generation multiple-action ophthalmic solution was safe and clinically effective in the treatment of moderate and severe dry eye, with significant improvements in the main ocular surface parameters.

Neurotrophic Keratopathy in Systemic Diseases: A Case Series on Patients Treated With rh-NGF.

Purpose: To evaluate the prevalence, clinical ocular presentation and corneal healing in moderate and severe neurotrophic keratopathy (NK) caused by systemic diseases and treated with rh-NGF. Setting: Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Ophthalmology Clinic, University of Messina, Italy. Design: Retrospective observational study of case series. Materials and Methods: In this retrospective observational study 11 patients (five female and six males) aged from 24 to 88 years (55.4 ± 21.3 years) with moderate and severe NK caused by systemic diseases were enrolled. The VAS questionnaire was dispensed. The ocular examination comprised slit lamp evaluation, ocular surface assessment with Keratograph 5M (Oculus, Germany), corneal sensitivity with Cochet-Bonnet esthesiometer (Lunneaux, France) and corneal thickness measurement with AC-OCT (DRI, Triton, Topcon, Japan). The underlying systemic causes of NK were determined. Results: The main cause of NK was post-neuroma surgery (36%), followed by diabetes (18%). The remaining causes were rheumatoid arthritis (9%), post-traumatic (9%), post-surgery (9%), atopia (9%), Graves' disease (9%). Seven eyes presented severe grade of NK with corneal ulcer and in four a moderate grade was registered. The rh-NGF (Cenegermin) was administered with a standard protocol one drop six times daily for 8 weeks. The complete healing of all corneal defects was registered at the end of the treatment. Conclusions: The post-neuroma surgery was the most common cause of NK and severe grade was clinically more represented. The rh-NGF proved effective to promote corneal recovery with all defects healed after the treatment.

Clinical and instrumental assessment of the corneal healing in moderate and severe neurotrophic keratopathy treated with rh-NGF (Cenegermin).

PURPOSE: To evaluate corneal healing in patients with moderate and severe neurotrophic keratitis (NK) treated with topical rh-NFG (Cenegermin). METHODS: Twenty-one patients (12F and 9M) aged from 21 to 93 years (62.5 ± 19.4) with moderate and severe NK were enrolled in the study. The patients were divided into 2 groups accordingly to the severity of the disease. The underlying causes of NK were determined. The VAS questionnaire was dispensed. The ocular examination comprised slit lamp evaluation, ocular surface assessment with Keratograph 5M (Oculus, Germany), corneal sensitivity with Cochet-Bonnet esthesiometer (Lunneaux, France) and corneal thickness measurement with AC-OCT (DRI, Triton, Topcon, Japan). The drops of Cenegermin 0.002% were administrated 6 times daily for 8 weeks. All participants were evaluated at baseline, after 4 and 8 weeks of the treatment. The area of corneal defect with maximum diameter less than 0.5 mm was considered as healed. The main outcome measures were corneal healing, corneal sensitivity recovery and corneal thickness in the ulcer group. RESULTS: The herpetic keratitis was the most common cause of NK. Thirteen eyes were affected by severe grade of NK with corneal ulcer and 8 eyes presented a moderate grade. After 8 weeks a complete healing of the corneal defects was registered both in moderate and severe NK. Significant increase of the corneal sensitivity and thickness were registered. CONCLUSIONS: The rh-NGF (Cenegermin) resulted effective in the treatment of the severe and moderate NK with significant recovery of the corneal sensitivity and healing of the corneal defects in both groups.

The Role of Hi-Tech Devices in Assessment of Corneal Healing in Patients with Neurotrophic Keratopathy.

To prove the role of high-tech investigation in monitoring corneal morphological changes in patients with neurotrophic keratopathy (NK) using Keratograph 5M (K5M) and anterior segment OCT (AS-OCT), corneal healing was monitored with Keratograph 5M (Oculus, Wetzlar, Germany) and AS-OCT (DRI, Triton, Topcon, Tokyo, Japan) in 13 patients (8F and 5M), aged from 24 to 93 years (67.8 ± 19) with severe NK, who were treated with Cenegermin 0.002% (20 µg/mL) (Oxervate®, Dompè, Farmaceutici Spa, Milan, Italy). The surface defects were evaluated on Keratograph 5M with ImageJ software and the corneal thickness variations were measured using DRI-Triton OCT software. Instrumental procedures were performed at baseline, and after 4 and 8 weeks of the treatment, respectively. The main outcome measures were reduction of the ulcers' area and corneal thickness recovery. The mean area of the corneal ulcers was reduced between baseline and 4 weeks examination in all patients, and at 8 weeks all ulcers were completely healed. An increase of the corneal thickness was evidenced between the baseline visit and after the 4- and 8-week follow-up, respectively. Additionally, only in collaborating subjects the In Vivo Confocal Microscopy (IVCM) was performed with HRT Rostock Cornea Module (Heidelberg Eng GmbH) to study the corneal nerves fibres. High-tech diagnostics with K5M, AS-OCT and IVCM proved useful in the assessment of corneal morphology and the healing process in patients with NK and could be extended to assess other corneal pathologies.

The Propeller Myocutaneous Flap of the Upper Eyelid: Anatomical Study and its Clinical Implication.

BACKGROUND: The reconstruction of the upper eyelid and the periorbital region is a challenge for the surgeon. The aims of this reconstruction are to guarantee protection to the eyeball, maintain the visual field, and restore the function of the eyelid without damaging other anatomical structures. In this study, the authors describe the use of a propeller myocutaneous flap based on the small vertical branches of marginal, peripheral ed superficial arcade, for the reconstruction of the upper eyelid or periorbital region. MATERIALS AND METHODS: The authors enrolled 3 patients (Caucasian), between 2018 and 2019, and subjected to reconstructive surgery with the propeller myocutaneous flap of the periorbital region at the Plastic Surgery Unit of the University of Messina. The vascularization of the flap was demonstrated through an anatomical study conducted on cadavers at the dissection laboratories of the University of Bordeaux 2. RESULTS: The authors have shown that the myocutaneous flap represents a valid alternative for loss of substance coverage and reconstruction of the upper eyelid or periorbital region, allowing the achievement of a good aesthetic and functional result. FOLLOW UP: Patients were followed up at 3-6-12 months. No complications were reported (flap retraction, periocular region deformity, donor site morbidity). Furthermore, at the last visit, the scars were almost invisible. CONCLUSIONS: The use of the propeller myocutaneous flap of the upper eyelid is a valid reconstructive alternative to the standard techniques described so far for the reconstruction of the periorbital region.

Combined Phialemonium curvatum and Acanthamoeba Keratitis: The Importance of Early Diagnosis and Specific Therapy.

PURPOSE: To report the clinical and confocal findings of a unique case of combined Phialemonium curvatum and Acanthamoeba keratitis and to highlight the role of the prompt diagnosis and specific medical treatment in preserving visual function. METHODS: A case report and literature review. RESULTS: A 54-year-old woman presented with a 3-day history of visual impairment, photophobia, and ocular pain in her right eye. Her best corrected visual acuity was 0.4 Logarithm of the Minimum Angle of Resolution scale, and the slit-lamp examination showed whitish corneal stromal infiltrate with satellite lesions. In vivo confocal microscopy evidenced Acanthamoeba cysts and fungal hyphae that resulted P. curvatum in the culture examination. The intensive medical treatment was started with topical 0.02% polyhexamethylene biguanide, voriconazole 1%, and moxifloxacin hydrochloride 0.5%. Progressive improvement of clinical and confocal pictures was registered with a complete recovery of visual function after 1 month. CONCLUSIONS: This is the first case report of combined P. curvatum and Acanthamoeba keratitis. The fast diagnosis with in vivo confocal microscopy allowed early and intensive specific treatment with recovery of corneal infection.

Oral Aminoacids Supplementation Improves Corneal Reinnervation After Photorefractive Keratectomy: A Confocal-Based Investigation.

Aim of this retrospective study was to estimate the effect of oral supplementation with amino acids (AA) on corneal nerves regrowth after excimer laser refractive surgery with photorefractive keratectomy (PRK). Based on the pre and post-surgical treatment received, 40 patients with 12 months of follow-up were distributed in two groups: 20 patients had received oral AA supplementation 7 days before and 30 days after PRK, and 20 patients without AA supplementation, as untreated reference control. All patients followed the same standard post-operative topical therapy consisting of an association of antibiotic and steroid plus sodium hyaluronate during the first week, then steroid alone progressively decreasing during 30 days and sodium hyaluronate for the following 3 months. In vivo corneal confocal microscopy was used to evaluate the presence of sub-basal corneal nerve fibers during 12 months after PRK. Results have shown that sub-basal nerves regenerated significantly faster (p <0.05), and nerve fibers density was significantly higher (p <0.05) with a more regular pattern in the eyes of AA treated patients with respect to the untreated control group. Therefore, our data indicate that oral supplementation with AA improved significantly corneal nerve restoration after PRK and could thus be considered as an additional treatment during corneal surgical procedures.

Use of Lacrimal Symptoms Questionnaire After Punctoplasty Surgery: Retrospective Data of Technical Strategy.

ABSTRACT: The goal of this study is to evaluate postpunctoplasty symptoms with lacrimal symptoms questionnaire (Lac-Q). A retrospective study was conducted on 31 patients (14 men and 17 woman) with a diagnosis of canalicular stenosis: 26 patients with unilateral occlusion and 5 patients with bilateral occlusion. The Lac-Q was administered preoperative and at 1, at 3, and at 6 months following the surgery. Moreover, the Lac-Q questionnaire was administered by an independent observer (SI). The mono-lateral and bilateral postoperative Lac-Q score showed a significant improvement of symptoms at 1, 3, and 6 months than the preoperative results. The Lac-Q questionnaire is a way to evaluate the quality of outcomes after punctoplasty surgery. In this study, all patients showed a significant improvement of symptoms after surgery.

Ophthalmologic Manifestations of Primary Sjögren's Syndrome.

Sjögren's syndrome (SS) is a chronic, progressive, inflammatory, autoimmune disease, characterized by the lymphocyte infiltration of exocrine glands, especially the lacrimal and salivary, with their consequent destruction. The onset of primary SS (pSS) may remain misunderstood for several years. It usually presents with different types of severity, e.g., dry eye and dry mouth symptoms, due to early involvement of the lacrimal and salivary glands, which may be associated with parotid enlargement and dry eye; keratoconjunctivitis sicca (KCS) is its most common ocular manifestation. It is still doubtful if the extent ocular surface manifestations are secondary to lacrimal or meibomian gland involvement or to the targeting of corneal and conjunctival autoantigens. SS is the most representative cause of aqueous deficient dry eye, and the primary role of the inflammatory process was evidenced. Recent scientific progress in understanding the numerous factors involved in the pathogenesis of pSS was registered, but the exact mechanisms involved still need to be clarified. The unquestionable role of both the innate and adaptive immune system, participating actively in the induction and evolution of the disease, was recognized. The ocular surface inflammation is a central mechanism in pSS leading to the decrease of lacrimal secretion and keratoconjunctival alterations. However, there are controversies about whether the ocular surface involvement is a direct autoimmune target or secondary to the inflammatory process in the lacrimal gland. In this review, we aimed to present actual knowledge relative to the pathogenesis of the pSS, considering the role of innate immunity, adaptive immunity, and genetics.

Multimodal Imaging in Susac Syndrome: A Case Report and Literature Review.

Susac syndrome (SS) is a rare microangiopathy that involves arterioles of the brain, retina, and cochlea. Diagnosis is extremely difficult because of the rarity of the disease and because the signs and symptoms often occur at different times. Multidisciplinary approaches and multimodal images are mandatory for diagnosis and prompt therapy. In this report, we describe a case of SS and the application of multimodal retinal imaging to evaluate the ophthalmologic changes and to confirm diagnosis. Early diagnosis and therapy based on the associations of steroids and immunosuppressants are necessary to limit the sequelae of the disease.

The ocular microbiome and microbiota and their effects on ocular surface pathophysiology and disorders.

The ocular surface flora perform an important role in the defense mechanisms of the ocular surface system. Its regulation of the immunological activity and the barrier effect against pathogen invasion are remarkable. Composition of the flora differs according to the methods of investigation, because the microbiome, composed of the genetic material of bacteria, fungi, viruses, protozoa, and eukaryotes on the ocular surface, differs from the microbiota, which are the community of microorganisms that colonize the ocular surface. The observed composition of the ocular surface flora depends on harvesting and examining methods, whether with traditional culture or with more refined genetic analysis based on rRNA and DNA sequencing. Environment, diet, sex, and age influence the microbial flora composition, thus complicating the analysis of the baseline status. Moreover, potentially pathogenic organisms can affect its composition, as do various disorders, including chronic inflammation, and therapies applied to the ocular surface. A better understanding of the composition and function of microbial communities at the ocular surface could bring new insights and clarify the epidemiology and pathology of ocular surface dynamics in health and disease. The purpose of this review is to provide an up-to-date overview of knowledge about this topic.

Optical Coherence Tomography Predictors of Favorable Functional Response in Naïve Diabetic Macular Edema Eyes Treated with Dexamethasone Implants as a First-Line Agent.

PURPOSE: To evaluate efficacy and safety of intravitreal dexamethasone 0.7 mg implant in treatment-naïve DME patients and to assess the utility of OCT structural biomarkers as predictors of functional response after treatment. METHODS: Thirty-nine eyes of 39 diabetic patients with center involving DME were enrolled. Best-corrected visual acuity (BCVA) and SS-OCT (DRI SS-OCT Triton, Topcon, Japan) to evaluate central retinal thickness (CRT), serous retinal detachment (SRD), intraretinal cysts (IRC), number of hyper-reflective spots (HRS), integrity of the ellipsoid zone (EZ), disorganization of the inner retinal layers (DRIL), vitreomacular adhesion (VMA), vitreomacular traction (VMT), and posterior vitreous detachment (PVD) were evaluated at baseline and at 3, 6, and 12 months after treatment. Multiple logistic analysis was performed to evaluate the possible OCT biomarker as predictive factors for final visual acuity improvement at the end of treatment. RESULTS: At 12 months after treatment, the mean BCVA improved from 51.6 ± 17.5 to 56.9 ± 17.3 ETDRS letters (p=0.03). Furthermore, there were statistically significant changes in CRT, IRC, HRS, and SRD. Nineteen patients presented a >10-letters improvement in BCVA; the presence of SRD at baseline was a predictor of good functional treatment response at 12 months (OR 2.1; 95% C.I. 1.2-4.9; p=0.001) as well as the presence of EZ integrity preoperatively (OR 1.3; 95% C.I. 0.5-2.4; p=0.001) and the absence of vitreoretinal interface alteration (OR 1.1; 95% C.I. 0.3-2.3; p=0.02). No significant changes in the IOP and lens status were observed throughout the follow-up period. CONCLUSION: This study empathized the importance of structural biomarkers as predictors of favorable response and confirmed the efficacy and safety of intravitreal dexamethasone implant in treatment-naïve DME patients showing a better functional response in the presence of SRD integrity of EZ and absence of vitreoretinal alterations.

Impact of corneal parameters, refractive error and age on density and morphology of the subbasal nerve plexus fibers in healthy adults.

The purpose of this study was to analyze corneal sub-basal nerve plexus (SBNP) density and morphology and their relationships with corneal parameters and refractive status. In this single center study, in vivo confocal microscopy (IVCM) was performed in 76 eyes of 38 healthy subjects aged 19-87 (mean age 34.987 ± 1.148). Nerve fiber analysis was performed using Confoscan 4 microscope with semi-automated software (Nidek Technologies, Italy) The nerve fiber length (NFL) µm/mm2, nerve fiber density (NFD) no./mm2, tortuosity coefficient (TC), and nerve beadings density (NBD) no./mm were considered. Relationship between SBNP parameters and corneal curvature, thickness, diameter, and refraction were analyzed. Additionally, the association with gender, laterality and age were determined. NFL was inversely correlated with age (r = - 0.528, p < 0.001), myopic refractive error (spherical value) (r = - 0.423, p < 0.001), and cylindrical power (r = - 0.340, p = 0.003). NFD was inversely correlated with age (r = - 0.420, p < 0.001) and myopic refractive error (r = - 0.341, p = 0.003). NBD showed a low inverse correlation with cylindrical power (r = - 0.287, p = 0.012) and a slight positive correlation with K (r = 0.230, p = 0.047). TC showed a significant negative correlation between age (r = - 0.500, p < 0.001) and myopic refractive error (r = - 0.351, p = 0.002). Additionally, there were strong positive correlations between NFL and NFD (r = 0.523, p < 0.001), NFL and TI (r = 0.603, p < 0.001), and NFD and TC (r = 0.758, p < 0.001). Multiple regression analysis revealed age to be the most significant factor affecting SBNP density (B = - 0.467, p = 0.013) and length (B = - 61.446, p < 0.001); myopic refractive error reduced both SBNP density (B = - 2.119, p = 0.011) and length (B = - 158.433, p = 0.016), while gender and laterality had no significant effects (p > 0.005). SBNP fiber length decreases with age, myopic refractive error and cylindrical power. SBNP fiber density reduces with age and myopic refractive error. Corneal nerve parameters are not influenced by gender or laterality.