COMPARISON OF RETROBULBAR, SUB-TENON ANESTHESIA AND MEDIAL CANTHUS EPISCLERAL ANESTHESIA FOR 25-GAUGE POSTERIOR VITRECTOMY.

PURPOSE: The aim of the study is to compare the efficacy, safety, and globe akinesia between retrobulbar anesthesia, sub-Tenon anesthesia, and medial canthus episcleral anesthesia for 25-gauge posterior vitrectomy. METHODS: A total of 340 25-gauge vitrectomy data sheets were retrospectively collected between November 2017 and June 2019. Ninety patients were included in the study. These patients were matched by sex and age to receive retrobulbar anesthesia (group 1, n = 30), sub-Tenon anesthesia (group 2, n = 30), and medial canthus episcleral anesthesia (group 3, n = 30). Globe akinesia was recorded after the injection of anesthetic at 2, 5, and 10 minute time intervals. Patients were asked to rate the pain during administration of anesthesia, during surgery, and postoperatively using the visual analog pain scale. RESULTS: For a perfect block, at 10 minutes, retrobulbar outperformed both sub-Tenon and medial canthus episcleral anesthesia which seemed quite similar. During administration, the three techniques did not show statistically different effects on pain. Regarding perioperative pain, retrobulbar outperformed medial canthus episcleral anesthesia. CONCLUSION: All three techniques allowed for safe surgery. Retrobulbar obtained the best results, although sub-Tenon proved to be a valid alternative. Medial canthus episcleral anesthesia obtained mostly good and fair blocks and acceptable pain levels during surgery. Further studies should investigate whether optimal anesthetic efficacy can be obtained with sub-Tenon and medial canthus episcleral techniques when higher volumes are used.

EARLY MICROVASCULAR AND NEURAL CHANGES IN PATIENTS WITH TYPE 1 AND TYPE 2 DIABETES MELLITUS WITHOUT CLINICAL SIGNS OF DIABETIC RETINOPATHY.

PURPOSE: To assess and compare early modifications in inner retinal layer thickness and optical coherence tomography angiography parameters in patients with diabetes mellitus (DM) Types 1 and 2 without clinical signs of diabetic retinopathy. METHODS: Ninety eyes of 90 subjects (24 Type 1 DM, 36 Type 2 DM, and 30 healthy controls) were prospectively evaluated with spectral domain OCT, swept-source OCT angiography, and color fundus photography (on the same day). Retinal nerve fiber layer, ganglion cell layer (GCL+), and nerve fiber layer + GCL+ (GCL++) thickness were automatically determined by the instrument in the 1, 3, and 6 central mm. On OCT angiography, the following parameters were evaluated: area of foveal avascular zone, number of focally dilated endings of the capillaries (detected only on OCT angiography), presence of regular/irregular foveal avascular zone, capillary loss, and capillary network irregularities in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). RESULTS: Ganglion cell layer+ (P = 0.0099) and GCL++ (P = 0.0367) were significantly thicker in DM Type 1 versus DM Type 2 in 1 central mm, after adjustment for age and DM duration. The area of foveal avascular zone was significantly larger in DM Type 1 versus controls in both SCP and DCP and in DM Type 1 versus Type 2 only in DCP (P < 0.05 for all); the number of focally dilated endings of the capillaries was higher in DM Type 1 versus controls in both SCP and DCP (P < 0.01 for all); and in DM Type 2 versus controls only in DCP (P = 0.007). Perifoveal capillary loss in SCP and inner retinal layer thickness had the highest correlation in both DM types. CONCLUSION: There are specific neural and microvascular modifications even before clinical signs of diabetic retinopathy in DM Types 1 and 2. Perifoveal capillary loss in the SCP is highly correlated with inner retinal layer. These data may help in characterization of patients at the preclinical stage of diabetic retinopathy.

MORPHOFUNCTIONAL EVALUATION IN DOME-SHAPED MACULA: A MICROPERIMETRY AND OPTICAL COHERENCE TOMOGRAPHY STUDY.

PURPOSE: To investigate retinal sensitivity (Se) in dome-shaped macula (DSM) using microperimetry and to correlate functional findings to specific spectral domain optical coherence tomography features. METHODS: Patients affected by DSM in at least 1 eye were consecutively enrolled in a prospective, cross-sectional study. All studied eyes performed best-corrected visual acuity measurement, microperimetry to assess Se and optical coherence tomography to investigate DSM pattern and to measure bulge height and retinal and choroidal thicknesses. RESULTS: Fifty-three eyes of 29 patients were studied. Dome-shaped macula was vertically oriented (V-DSM) in 23 (43.4%), symmetric (S-DSM) in 17 (32.1%), and horizontally oriented (H-DSM) in 13 eyes (24.5%). Foveal subretinal fluid was present in 29/53 (54.7%) cases; it correlated to the bulge height (P < 0.0001) and determined a reduction of Se (P < 0.0001) not of best-corrected visual acuity (P = 0.7105). Mean Se was 13.9 ± 3.2 dB. Microperimetry parameters did not differ among the different DSM patterns. However, Se was significantly impaired if foveal subretinal fluid was present in V-DSM and in S-DSM, but not in H-DSM (V-DSM: P < 0.0001; S-DSM: P = 0.0252; H-DSM: P = 0.5723). In H-DSM, inferior choroidal thickness was thicker in cases with foveal subretinal fluid compared with those without it (P = 0.0363). CONCLUSION: In DSM, Se evaluation better reflects the central functional impairment than best-corrected visual acuity, particularly when some optical coherence tomography features, such as foveal subretinal fluid and higher bulge height, are present.

HYPERREFLECTIVE RETINAL SPOTS IN NORMAL AND DIABETIC EYES: B-Scan and En Face Spectral Domain Optical Coherence Tomography Evaluation.

PURPOSE: To evaluate hyperreflective retinal spots (HRS), in normal subjects and diabetic patients without and with macular edema (diabetic macular edema, DME), on linear B-scans and corresponding en face image of spectral-domain optical coherence tomography. METHODS: Retrospective evaluation of images of 54 eyes/subjects (16 normal subjects, 19 diabetic patients without DME, and 19 with DME). On horizontal B-scan spectral-domain optical coherence tomography, passing through the center of the fovea, the following characteristics of HRS were evaluated: location (inner retina or outer retina), size (≤30 or >30 µm), reflectivity (similar to nerve fiber layer or to retinal pigment epithelium-Bruch complex), and presence or absence of back shadowing. On en face spectral-domain optical coherence tomography, the following patterns were evaluated: 1) isolated HRS (not corresponding to any visible lesion); 2) HRS corresponding to a segment of retinal capillary or microaneurysm wall; and 3) HRS corresponding to hard exudate. All gradings were performed twice by two graders in a masked fashion. RESULTS: Size ≤30 µm, reflectivity similar to nerve fiber layer, and absence of back shadowing were associated with absence of vessels or any other lesion on en face image (P = 0.0001 for all). Size >30 µm, reflectivity similar to retinal pigment epithelium-Bruch complex, presence of back shadowing, and location in the outer retina were all associated with presence of hard exudate on en face imaging (P < 0.0001 for all). Multiple logistic regression analysis showed that HRS present in the inner retina (P < 0.0001), size >30 µm (P = 0.0029), and presence of back shadowing (P < 0.0001) are directly associated with presence of microaneurysms on en face image. Intragrader and intergrader repeatability were excellent for all evaluations. CONCLUSION: Hyperreflective retinal spots ≤30 µm, reflectivity similar to nerve fiber layer, and absence of back shadowing may represent activated microglial cells; HRS >30 µm, reflectivity similar to retinal pigment epithelium-Bruch complex, presence of back shadowing, and location in the outer retina may represent hard exudate; HRS >30 µm, presence of back shadowing, and location in the inner retina may represent microaneurysms. These hypotheses may be tested in further studies.

HYPERREFLECTIVE RETINAL SPOTS AND VISUAL FUNCTION AFTER ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR TREATMENT IN CENTER-INVOLVING DIABETIC MACULAR EDEMA.

BACKGROUND: To assess and correlate early modifications in hyperreflective retinal spots (HRS), retinal sensitivity (RS), fixation stability, and best-corrected visual acuity (BCVA) after anti-vascular endothelial growth factor treatment in naive center-involving diabetic macular edema. METHODS: Cross-sectional comparative case-control series. Twenty diabetic patients underwent 3 consecutive intravitreal anti-vascular endothelial growth factor injections in the study eye (20 fellow eyes served as control), full ophthalmologic examination including spectral domain optical coherence tomography (Retinascan RS-3000; Nidek, Gamagori, Japan), and microperimetry (MP1; Nidek) at baseline (Visit-V1), 1 month after each injection (V2, V3, V4), and at 6 months (V5). Central retinal thickness, inner and outer retinal thickness, number of HRS, BCVA, RS, and bivariate contour ellipse area were evaluated by analysis of variance test with Bonferroni post hoc test. Correlation analyses were performed by Spearman correlation. RESULTS: In treated eyes, central retinal thickness and inner retinal thickness significantly decreased at V2, V3, V4 versus V1 (P < 0.03 at least for all); the mean number of HRS significantly decreased in both inner and outer retina at all follow-up visits versus V1 (P < 0.008 at least for all); mean RS and bivariate contour ellipse area remained statistically unchanged during the follow-up; BCVA significantly improved at V3, V4, and V5 versus V1 (P = 0.009 at least for all). In fellow eyes, central retinal thickness, HRS, RS, and BCVA did not change at any follow-up. The number of HRS correlated inversely with RS, directly with bivariate contour ellipse area, and not significantly with BCVA. CONCLUSION: A significant decrease in HRS in the retina after anti-vascular endothelial growth factor treatment is documented. A decrease in HRS correlates with functional parameters, specifically RS. New parameters may be used for treatment evaluation in center-involving diabetic macular edema.

Risk Factors and Age-Related Macular Degeneration in a Mediterranean-Basin Population: The PAMDI (Prevalence of Age-Related Macular Degeneration in Italy) Study--Report 2.

AIM: To investigate the association of diet and other modifiable risk factors with the prevalence of age-related macular degeneration (ARMD) in rural and urban communities of a Mediterranean population in the northeast of Italy. METHODS: A cross-sectional population-based study was conducted among subjects aged over 60 years. A food frequency questionnaire (FFQ) was used to assess the consumption of different food categories, i.e., protective (P), risky (R), lutein-rich (L) and neutral (N). Smoking habit and alcohol intake were also examined. Macular pigment was measured by Raman spectroscopy. RESULTS: P food intake reduced the risk of large drusen (ARM2; OR 0.93; 95% CI 0.89-0.96) within the rural community. In this sub-group, R foods resulted in a slight association with large drusen, though the R/P food ratio was highly correlated with ARM2 (OR 1.21; 95% CI 1.12-1.31). Raman measures showed an age-dependent decrease but did not correlate with lutein intake. Smoking habit showed a positive association with ARM2 among women (OR 2.40; 95% CI 1.54-3.75), whereas alcohol consumption resulted in protective odds (OR 0.72; 95% CI 0.60-0.86). CONCLUSION: FFQ analysis confirmed the role of P and R foods and the benefit of a Mediterranean diet in ARMD. Moderate alcohol consumption showed a beneficial effect, whereas the deleterious role of a smoking habit was more evident in females.

SUBTHRESHOLD MICROPULSE YELLOW LASER VERSUS SUBTHRESHOLD MICROPULSE INFRARED LASER IN CENTER-INVOLVING DIABETIC MACULAR EDEMA: Morphologic and Functional Safety.

BACKGROUND: To evaluate and compare in vivo retinal and choroidal morphologic changes and macular function in patients treated with yellow (Y-MPL) or infrared (IR-MPL) subthreshold micropulse laser in center-involving diabetic macular edema. METHODS: Prospective, randomized, single institution, comparative 6-month pilot study of 53 eyes (53 patients with diabetes). Inclusion criteria were previously untreated center-involving diabetic macular edema with central retinal thickness ≤400 µm (mild diabetic macular edema). Y-MPL or IR-MPL treatment was performed in a standardized pattern, using in both cases the lowest duty cycle (5%). Morphologic outcomes were the visibility of laser spots (on color fundus photographs [COL], fundus autofluorescence, fluorescein angiography, and spectral domain optical coherence tomography), retinal thickness and volume changes, foveal choroidal thickness changes, and integrity and reflectivity of the outer retinal layers. Visual function outcomes were variation in mean 4° and 12° retinal sensitivity and best-corrected visual acuity. RESULTS: Twenty-six eyes were treated with Y-MPL and 27 eyes with IR-MPL. No visible laser spots on the retina were found on COL, fundus autofluorescence, and fluorescein angiography in both treatment groups at 3 months and 6 months of follow-up. Central retinal thickness, macular volume, foveal choroidal thickness, and best-corrected visual acuity were not significantly different at any follow-up visit between the two treatment groups. There were no changes in the integrity of the external limiting membrane or inner segment/outer segment junction in both treatment groups. Mean central 4° retinal sensitivity increased in both treatment groups at 6 months (P = 0.01 and P = 0.04, respectively). Mean central 12° retinal sensitivity increased in the Y-MPL group only (P = 0.047). But, there was no significant difference in mean 4° and 12° retinal sensitivity between the 2 treatment groups at any follow-up visit. CONCLUSION: No clinically visible or invisible scars in the macula were found after Y-MPL or IR-MPL treatment. Both Y-MPL and IR-MPL with the lowest duty cycle (5%) and fixed power parameters seem to be safe from the morphologic and visual function points of view in mild center-involving diabetic macular edema.

Extent of diabetic macular edema by scanning laser ophthalmoscope in the retromode and its functional correlations.

BACKGROUND: To determine whether scanning laser ophthalmoscope in the retromode (RM-SLO) is useful to evaluate the extent of diabetic macular edema (DME) and its functional characteristics. METHODS: Comparative case series of 37 eyes (27 patients with diabetes). Inclusion criteria were: center involving DME determined by optical coherence tomography; RM-SLO, optical coherence tomography, fluorescein angiography (FA), and microperimetry performed on the same day; no significant media opacities. Two masked retinal specialists independently graded all images. The full extent of DME areas and two grades (small and large) DME areas were separately evaluated. The relationship between the DME extent obtained by RM-SLO and FA was assessed by Pearson correlation coefficient, intraclass correlation coefficient, and Bland-Altman plot. T-test was used to compare DME extent to central retinal thickness and macular sensitivity. RESULTS: The values of RM-SLO from the right and left prospective were highly correlated in the evaluation of the extent of DME (rho = 0.99, P < 0.0001). Mean DME area on RM-SLO was 5.7 + 5.6 mm (range, 0.3-18.2 mm); mean DME area on FA was 6.4 + 5.9 mm (range, 0.3-19.7 mm). The correlation between RM-SLO and FA in the evaluation of DME extent was highly significant (rho = 0.97, P < 0.0001), even when DME extent was divided in 2 major areas (intraclass correlation coefficient >0.8, P < 0.0001). The correlation between retinal sensitivity and DME area (RM-SLO) was significant (rho = -0.61, P = 0.0003). CONCLUSION: The extent has become an important parameter for monitoring DME, with or without treatment. The extent of DME well correlates with functional data, mainly retinal sensitivity. Retromode SLO can be reliably and easily used in the evaluation of DME extent, avoiding the use of invasive FA.

Coexistence of neuropathic corneal pain, corneal nerve abnormalities, depression, and low quality of life.

PURPOSE: To evaluate the quality of life (QoL), mental health conditions and corneal morphology in neuropathic corneal pain (NCP) subjects without a significant ocular surface disease. METHODS: A composite questionnaire was administered to 228 consecutive subjects, assessing the pain intensity, duration, and quality using a modified version of the Self-Administered Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS) and Pain Detect (PD) questionnaires. Subjects diagnosed with possible central NCP and two sub-groups of patients diagnosed with peripheral ocular pain completed an additional battery of mental health questionnaires and were examined by In Vivo Confocal Microscopy (IVCM). RESULTS: Of the 76 subjects that reported chronic ocular pain (duration >1 month), 53 were classified with probable NCP. Nine subjects without signs that justify the pain and non-responding to topical anaesthesia, were considered affected by central NCP. In these patients, a significant negative correlation was found between the presence pain and the mental component of the QoL (R2 = 0.733), and a positive correlation between the severity of pain the presence post-traumatic stress disorder (R2 = 0.83) and depression (R2 = 0.93). Although neuromas and sprouting had higher frequency in the central NCP group compared the control groups, these differences was not statistically different. CONCLUSIONS: The assessment of ocular pain characteristics using multiple questionnaires and IVCM may help to recognize differences between nociceptive and neuropathic pain. An association between pain intensity and mental health condition may guide the therapeutical choices.

Endoplasmic Reticulum Stress and Unfolded Protein Response in Vernal Keratoconjunctivitis.

Purpose: Vernal keratoconjunctivitis (VKC) is an ocular allergic disease characterized by a type 2 inflammation, tissue remodeling, and low quality of life for the affected patients. We investigated the involvement of endoplasmic reticulum (ER) stress and unfolded protein response in VKC. Methods: Conjunctival imprints from VKC patients and normal subjects (CTs) were collected, and RNA was isolated, reverse transcribed, and analyzed with the Affymetrix microarray. Differentially expressed genes between VKC patients and CTs were evaluated. Genes related to ER stress, apoptosis, and autophagy were further considered. VKC and CT conjunctival biopsies were analyzed by immunohistochemistry (IHC) with specific antibodies against unfolded protein response (UPR), apoptosis, and inflammation. Conjunctival fibroblast and epithelial cell cultures were exposed to the conditioned medium of activated U937 monocytes and analyzed by quantitative PCR for the expression of UPR, apoptosis, autophagy, and inflammatory markers. Results: ER chaperones HSPA5 (GRP78/BiP) and HYOU1 (GRP170) were upregulated in VKC patients compared to CTs. Genes encoding for ER transmembrane proteins, PKR-like ER kinase (PERK), activating transcription factor 6 (ATF6), ER-associated degradation (ERAD), and autophagy were upregulated, but not those related to apoptosis. Increased positive reactivity of BiP and ATF6 and unchanged expression of apoptosis markers were confirmed by IHC. Cell cultures in stress conditions showed an overexpression of UPR, proinflammatory, apoptosis, and autophagy markers. Conclusions: A significant overexpression of genes encoding for ER stress, UPR, and pro-inflammatory pathway components was reported for VKC. Even though these pathways may lead to ER homeostasis, apoptosis, or inflammation, ER stress in VKC may predominantly contribute to promote inflammation.

Efficacy and Satisfaction of Cyclosporine 0.1% in Patients with Vernal Keratoconjunctivitis.

Vernal keratoconjunctivitis (VKC) is a severe form of ocular allergy that compromises the quality of life of affected patients. Topical cyclosporine 0.1% cationic emulsion (CsA-CE) has been recently authorized for the treatment of severe VKC. We treated 29 VKC patients with on-label CsA-CE and recorded signs and symptoms, subjective patient's treatment satisfaction and the additional use of topical corticosteroids in case of exacerbations. CsA-CE was effective in reducing signs and symptoms in daily clinical practice. The overall subjective improvement of symptoms, efficacy of the treatment, tolerability to the drug and compliance reached a high level of subjective satisfaction score.55% of treated patients required the additional use of a 3-day course of topical dexamethasone with 1.13 ± 0.81 mean courses/month. In conclusions, VKC patients reported an overall high satisfaction with used the on-label topical CsA-CE with a limited use of additional topical corticosteroid treatment.

MicroCT detection of gunshot residue in fresh and decomposed firearm wounds.

Gunshot residue (GSR) evidence may be altered or obscured by after-death events such as putrefaction, autolysis, and/or damage by animals. The present study aimed at evaluating and comparing the amount and differential distribution of GSR utilizing microcomputed tomography (microCT) analysis of fresh and decomposed gunshot wounds. A total of 60 experimental shootings at three different firing distances (5, 15, and 30 cm) were performed on human calves surgically amputated for medical reasons. Thirty specimens (10 for each tested distance) were immediately formalin-fixed, while the other 30 specimens were enclosed in a cowshed for 15 days, before formalin fixation (air temperature ranging from 11°C to 38°C). MicroCT analysis with three-dimensional image reconstruction detected GSR particles in all the investigated entrance wounds. In fresh specimens, GSR was concentrated on the skin surface around the entrance hole and in the epidermis and dermis layers around the cavity, while in decomposed specimens, the high density particles were detected only in the dermis layer. No GSR was detected in exit wounds of both fresh and decomposed specimens regardless of the tested firing distance. Statistical analysis demonstrated that also in decomposed wounds the amount of GSR roughly correlated with the distance from which the gun was fired, exhibiting, however, a higher variability than in fresh samples. The obtained results suggest that microCT analysis can be a valid screening tool for differentiating decomposed entrance and exit gunshot wounds.

Macular and peripapillary choroidal thickness in diabetic patients.

PURPOSE: To investigate macular and peripapillary choroidal thickness (CT) in diabetic patients with and without diabetic retinopathy (DR). METHODS: One hundred and fifty subjects were enrolled: 102 diabetic patients (102 eyes) and 48 normals, as controls. Exclusion criteria were previously treated DR, refractive error higher than ± 3 diopters, and treated or untreated glaucoma. All patients underwent full ophthalmic examination, stereoscopic color fundus photography, and spectral domain optical coherence tomography (RS-3000; Nidek). Spectral domain optical coherence tomography examination consisted of linear scans, 6 mm in length, centered onto the fovea, and circle scan positioned around the optic disk (3.46 mm in diameter). Choroidal thickness was measured manually at the fovea and at 1, 2, and 3 mm distance along all scans in the macula. Peripapillary CT was measured at eight points along the circle scan. All measurements were performed independently by 2 masked graders. RESULTS: Mean age was not significantly different between patients with diabetes and controls. In the macular area, CT was significantly lower in the nasal quadrant versus all other quadrants (P < 0.0001), in both groups. In the peripapillary area, CT was significantly lower in the inferior quadrant versus all other quadrants (P < 0.05), in both groups. Mean macular and peripapillary CT progressively and significantly decreased with increasing level of DR (nonproliferative and proliferative DR vs. controls, P < 0.05). No significant CT difference was found between controls and diabetic eyes without detectable DR. Diabetic macular edema did not influence CT. Interobserver coefficient of repeatability was 28.8 (95% confidence interval, 24.8-32.8) for foveal measurements and 13.0 (95% confidence interval, 11.2-14.8) for peripapillary measurements. Pearson correlation coefficient was 0.99, and P <0.0001 for all measurements. CONCLUSION: Choroidal thickness is reduced in diabetic eyes and parallels appearance and evolution of DR. Spectral domain optical coherence tomography clearly confirms in vivo previously reported histopathologic observations. The role of choroid in the pathophysiology of DR needs to be adequately investigated.

Estimation of the firing distance through micro-CT analysis of gunshot wounds.

Estimation of the firing range is often critical for reconstructing gunshot fatalities, where the main measurable evidence is the gunshot residue (GSR). In the present study intermediate-range gunshot wounds have been analysed by means of a micro-computed tomography (micro-CT) coupled to an image analysis software in order to quantify the powder particles and to determine the firing distance. A total of 50 shootings were performed on skin sections obtained from human legs surgically amputated for medical reasons. For each tested distance (5, 15, 23, 30 and 40 cm), firing was carried out perpendicularly at the samples using a 7.65-mm pistol loaded with jacketed bullets. Uninjured skin sections were used as controls. By increasing the firing distance, micro-CT analysis demonstrated a clear decreasing trend in the mean GSR percentage, particularly for shots fired from more than 15 cm. For distances under 23 cm, the powder particles were concentrated on the epidermis and dermis around the hole, and inside the cavity; while, at greater distances, they were deposited only on the skin surface. Statistical analysis showed a nonlinear relationship between the amount of GSR deposits and the firing range, well explained by a Gaussian-like function. The proposed method allowed a good discrimination for all the tested distances, proving to be an objective, rapid and inexpensive tool for estimating the firing range in intermediate-range gunshot wounds.

The effects of the COVID-19 pandemic on the treatment of allergic eye diseases.

PURPOSE OF REVIEW: To analyze if recommendations given before and during the COVID-19 pandemic are still a valid option for patients suffering of ocular allergy (OA). RECENT FINDINGS: During the last year many doctors and patients requested suggestions for the treatment of OA patients in COVID-19 time. Most of them were given by phone calls and emails following the recommendations given by Scientific Societies. SUMMARY: Considering the current multiple problems related to the COVID-19 pandemic, OA has not been considered a priority, even though patients need treatments. Topical antiallergic drugs are still the first option to treat all kind of OA, with the addition of topical corticosteroids in the severe forms of vernal and atopic keratoconjunctivitis (VKC and AKC) even in patients at risk of COVID-19. Topical immunomodulation is still recommended in severe forms of VKC and AKC unless the patient is infected. The number of patients treated with these drugs in our Center was similar than previous years. The risk to have a VKC patient affected by COVID-19 is similar to the general pediatric population but with a lower OR. In 2021, still in COVID-time, the management of OA should follow the previous recommendations with an update due to the risk of infection.

Conjunctival transcriptome analysis reveals the overexpression of multiple pattern recognition receptors in vernal keratoconjunctivitis.

BACKGROUND: Vernal keratoconjunctivitis (VKC) is a chronic, potentially blinding ocular allergic disease affecting children with uncertain pathogenic mechanisms. OBJECTIVE: To identify differences in gene expression between VKC and normal subjects (CT) and to evaluate the expression of pattern recognition receptors (PRRs). METHODS: Conjunctival cells were collected by impression cytology device from 25 VKC patients and 10 CT. Isolated RNA was assayed with the NanoString human immunology codeset to evaluate the expression levels of immunology-related genes. RESULTS: Of the 579 genes, 398 were detected and 58 were significantly differently expressed in VKC compared to CT. The number of significantly differentially expressed genes (DEG) in the 3 different phenotypes vs CT were 149 in tarsal, 17 in limbal and 68 in the mixed form of VKC. The list of the most overexpressed genes included several chemokines (CCL24, CCL18, CCL22, CXCL1), proinflammatory cytokines (IL-1ß, IL-6, IL-8, TGFß-1) and genes related to Th2- and Th17-signaling families. Toll like receptors (TLR)4 and TLR8, Dectin-1/CLEC7A, mincle/CLEC4E, MCR1, NOD2 and NLRP3 and several of their pathway-related genes were significantly overexpressed in VKC. The number of DEG increased with the disease severity either in IgE+ or IgE- patients. Immunohistochemistry analysis of VKC conjunctival tissues confirmed an increased expression of these molecules at protein level. CONCLUSIONS: The increased expression of several chemotactic factors and co-stimulatory signals required for T-cell activation, confirms that VKC is mostly cell-mediated with local eosinophilia. The multiple expression of PRRs suggests a role of host-pathogens interaction in VKC development.