Repeatability of Automatic Measurements by an Anterior Segment Swept-Source OCT Biometer in Patients With Keratoconus.

PURPOSE: To evaluate the repeatability of automatic measurements of a new anterior segment optical coherence tomographer (ANTERION; Heidelberg Engineering) and their agreement with an anterior segment optical coherence tomography device combined with Placido disc corneal topography (MS-39; CSO) in patients affected by keratoconus. METHODS: Fifty-four consecutive patients were included. Three measurements were performed with the ANTERION and one with the MS-39. Repeatability was assessed by means of within-subject standard deviation, coefficient of variation (CoV), and intraclass correlation coefficient (ICC). Agreement was investigated with the 95% limits of agreement. The paired t-test and Wilcoxon matched-pairs test were performed to compare the measurements of the different devices. RESULTS: Repeatability of ANTERION measurements was high, with an ICC greater than 0.98 for all parameters. Many parameters revealed a CoV of less than 1% and a CoV within 5% was obtained for astigmatism measurements. The ANTERION measured a significantly higher corneal power and the MS-39 more negative posterior keratometric values. These differences were mirrored by a moderate agreement for mean simulated keratometry and poor agreement for total corneal power and posterior keratometry. CONCLUSIONS: The ANTERION revealed high repeatability of automatic measurements and good agreement with the MS-39 for many parameters in patients affected by keratoconus, but for most parameters the two instruments cannot be considered interchangeable. [J Refract Surg. 2024;40(7):e445-e452.].

Post-COVID simultaneous onset of Graves' disease and ocular myasthenia gravis in a patient with a complex ocular motility impairment.

A 74-years-old man experienced severe diplopia one month after recovery from an uncomplicated SARS-CoV-2 infection. Neurological examination was normal whereas ophthalmological examination showed bilateral exophthalmos with a complex ocular motility disorder characterized by a pseudo-internuclear ophthalmoplegia after fatigue associated to impairment of elevation and infraduction. Antibodies against TSH and acetylcholine receptors were positive; subsequent hormonal tests, ultrasonography of thyroid gland, single fiber electromyography and orbit MRI confirmed the diagnosis of concomitant Graves Disease (GD) and Myasthenia Gravis (MG). The coexistence between MG and GD is not rare but simultaneous onset after viral infection is very unsual. The complex ocular disorder simulated a deficit of the oculomotor nerve nuclei, and on clinical examination it posed some problems in the diagnosis. We suggest that recent SARS-COV-2 infection may have triggered a complex autoimmune response.

MOG-IgG positive optic neuritis after SARS-CoV-2 infection.

BACKGROUND: Many neurologic complications have been described after severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) including atypical cases of optic neuritis (ON), positive to myelin oligodendrocyte glycoprotein (MOG) IgG. OBJECTIVE: To report a case of MOG-IgG-associated ON and discuss why SARS-CoV-2 infection could be a potential trigger. METHODS: Retrospective single case report. RESULTS: We report a case of ON with positive MOG-IgG developed 15 days after presentation of SARS-CoV-2 infection. CONCLUSION: This report suggests that SARS-CoV-2 infection may have triggered autoantibodies production against MOG leading to ON.

A Novel Algorithm for the Evaluation of Corneal Nerve Beadings by in vivo Confocal Microscopy in Patients With Type 1 Diabetes Mellitus.

Purpose: Peripheral neuropathy could complicate diabetes mellitus (DM). In vivo confocal microscopy (IVCM) is an ocular examination for the diagnosis of small fiber neuropathies and the detection of the earliest corneal sub-basal nerve plexus (SBP) alterations. Corneal SBP characteristics include focal enlargement along with the nerve fiber, called corneal beadings. These dilatations represent a mitochondrial accumulation induced by the reactive oxygen stress, as a consequence of hyperglycemia. For this reason, corneal beadings are considered indicative of metabolic activity. This study aimed to describe the corneal characteristics of a population of type 1 diabetes mellitus (T1DM) well metabolically controlled, using a new algorithm for the analysis of corneal beading size (BS). Methods: Patients aged ≥18 years affected by T1DM were compared with healthy subjects who underwent IVCM (Confoscan 4; Nidek Technologies Padova, Italy). Starting from the coordinates of the beadings detected by the IVCM, we implemented a new algorithm for automatically measuring BS in corneal SBP images. Results: We compared 20 eyes of T1DM patients with 26 healthy controls. The corneal nerves' fiber length (p = 0.008), corneal nerves' fiber length density (p = 0.008), and the number of fibers (p = 0.017) were significantly lower in the diabetic group compared with controls. There was no difference between diabetic and healthy eyes in the mean number of corneal beadings both in the frame of analysis (p = 0.606) and for 0.1 mm of SBP nerve (p = 0.145). Regarding the BS, patients with T1DM had corneal beadings larger than controls (p = 0.036). Conclusions: We found that the corneal beadings parameters are similar in healthy and T1DM individuals. Nevertheless, measuring the BS with our algorithm, we showed that corneal beadings are enlarged in patients affected by T1DM when compared with healthy controls. Identifying beading expansion in corneal nerve fiber using IVCM should become a useful tool to predict peripheral neuropathy at an early stage.

Uveitis-Glaucoma-Hyphema Syndrome: Clinical Features and Differential Diagnosis.

PURPOSE: to study the clinical features of uveitis-glaucoma-hyphema (UGH) syndrome, particularly those useful for a differential diagnosis from unilateral hypertensive acute anterior uveitis. METHODS: A retrospective chart review was conducted on the clinical features of 9 patients with UGH syndrome. These features were then compared with those detected in 50 patients with unilateral hypertensive acute anterior uveitis. RESULTS: Fine and pigmented keratic precipitates (p = .0002 and p = .00004, respectively), iris atrophy (p = .0122), hyphema and vitreous opacities > 2+ (p = .0003), and cystoid macular edema (p = .009) were statistically associated with UGH syndrome. These clinical signs show a high specificity, ranging from 58 to 100%; the presence of pigmented keratic precipitates in the setting of a unilateral acute hypertensive anterior uveitis has a sensitivity and specificity of 89% and 84%, respectively. CONCLUSION: In patients operated on for cataract, UGH syndrome can be differentiated from unilateral hypertensive acute anterior uveitis considering specific clinical signs.

Corneal Subbasal Plexus in Eyes with Fuchs' Endothelial Corneal Dystrophy after Two Different Endothelial Surgeries.

PURPOSE: To evaluate the morphological features and density of corneal subbasal plexus (SBP) using in vivo corneal confocal microscopy (IVCCM) in patients affected by Fuchs' endothelial corneal dystrophy (FECD) six months after Descemet membrane endothelial keratoplasty (DMEK) and Descemet-stripping automated endothelial keratoplasty (DSAEK). METHODS: We included patients affected by FECD, requiring corneal endothelial surgery due to corneal oedema occurred from 3 to 6 months. 7 eyes underwent DMEK and 7 eyes DSAEK. All patients performed IVCCM preoperative and in six months postoperative. We analyzed SBP parameters, using CS4 Nerves Tracking Tool, and we studied the differences between the two endothelial keratoplasties. RESULTS: Comparing the eyes treated with DMEK with those treated with DSAEK, preoperative corneal thickness, corrected distance visual acuity (CDVA), and age were similar in both groups. SBP was not detectable at preoperative IVCCM in any eye. Postoperatively, the nerve fibers length, the nerve fibers density, the tortuosity, and the number of fibers and of branching did not differ in the eyes that underwent DMEK compared to DSAEK. The corneal beadings density was higher after DMEK than DSAEK, and this difference was statistically significant (P = 0.004). The type of endothelial keratoplasty was not associated with the presence or absence of postoperative corneal SBP (Pearson' chi-square, 0.755). CONCLUSIONS: Postoperative corneal reinnervation should be easily and noninvasively studied using IVCCM. Morphological postoperative features of SBP did not differ between two different types of endothelial keratoplasty, DMEK and DSAEK, despite the different sizes of the corneal incision. The lower beading density in the DSAEK group should be the consequence of a different distribution of mitochondria along the nerve fibers, as expression of a supposed higher metabolic distress in the DSAEK group.

Multimodal imaging characterization of peripheral drusen.

PURPOSE: To provide an integrate multimodal imaging characterization of peripheral drusen in the eyes with and without macular signs of age-related macular degeneration (AMD) and to analyze their association with macular findings. METHODS: In this retrospective, cross-sectional study, subjects with peripheral drusen were imaged with the Optos (Optos PLC, Dunfermline, Scotland, UK) and Spectralis devices to obtain referenced spectral domain optical coherence tomography (SD-OCT) images. Two experienced graders independently graded the ultra-widefield (UWF) pseudocolor and fundus autofluorescence (FAF) images for the presence of peripheral drusen and analyzed peripheral druse features using OCT. Main outcome measures included quantitative and qualitative assessment of peripheral drusen. RESULTS: Fifty-seven eyes (30 subjects) were included in the analysis. Mean ± SD age was 77.6 ± 9.2 years (range 54-97 years). On pseudocolor images, graders identified the presence of drusen in all the enrolled eyes (Cohen's kappa was 1.0). On FAF images, Cohen's kappa was 0.71. In the topographical assessment, peripheral drusen were detected in 23 cases in the temporal region, in 40 cases in the nasal region, in 40 cases in the inferior region, and in 42 cases in the superior region. On SD-OCT images, peripheral drusen had a high reflective core in 97.1% of cases, while remaining drusen were characterized by a low reflective core. The macula was affected by early/intermediate AMD in 23 eyes (43.5%) and late AMD in 6 eyes (10.5%). CONCLUSIONS: We provided an integrate multimodal imaging assessment of peripheral drusen in the eyes with and without AMD. Peripheral drusen were characterized by distinguished features that may suggest that these lesions constitute a distinct disease, rather than representing an expansion of AMD.

ALTERATIONS OF MACULAR BLOOD FLOW IN SUPERFICIAL AND DEEP CAPILLARY PLEXUSES IN THE FELLOW AND AFFECTED EYES OF PATIENTS WITH UNILATERAL IDIOPATHIC EPIRETINAL MEMBRANE.

PURPOSE: Previous research suggests that proliferation of the idiopathic epiretinal membrane (IERM) is related to microbreaks in the inner limiting membrane, which are caused by posterior vitreous detachment. In this study, we used optical coherence tomography angiography to determine whether a vascular defect in the inner retina is present before the mechanical damage caused by posterior vitreous detachment. METHODS: For patients with unilateral IERM (N = 23), optical coherence tomography angiography with blood flow measurement was performed in both eyes at the superficial capillary plexuses (SCP) and deep capillary plexuses (DCP) with 6 mm × 6-mm scans and ETDRS grids centered on the fixation point. These values were then compared with 45 healthy control eyes (CEs). RESULTS: The optical coherence tomography angiography data showed that blood flow was lower in the fellow eyes of IERM patients than in CEs when the whole enface macula (SCP: P = 0.031, DCP: P = 0.004) and extramacular area (SCP: P = 0.048, DCP: P = 0.026) were compared between groups. The blood flow was also lower in the affected eyes compared with CEs in both whole en face macula (SCP: P < 0.001, DCP: P < 0.001) and extramacular areas (SCP: P = 0.011, DCP: P < 0.001). CONCLUSION: Data from this study revealed that blood flow is significantly reduced in the fellow eyes of patients with unilateral IERM when compared with CEs. Overall, the data suggest that a vascular retinal defect could produce changes in the inner retina, preceding and influencing the formation of microbreaks occurring at the time of posterior vitreous detachment in the inner limiting membrane. Understanding the upstream mechanism of inner limiting membrane microbreaks may provide a therapeutic target aimed to ultimately prevent Mu[Combining Diaeresis]ller cells, astrocyte, and fibroblast migration, which cause IERM proliferation.

Optical Coherence Tomography Angiography Findings in Active and Inactive Ocular Behçet Disease.

PURPOSE: To study macular microvascular changes in ocular Behçet disease (OBD) using optical coherence tomography angiography (OCTA). METHODS: Quantitative and qualitative analyses of OCTA were performed on 23 OBD patients with active or inactive uveitis and compared with healthy controls. RESULTS: Deep capillary plexus (DCP) is the most frequently involved in OBD (p < 0.001). Its vessel density (VD) is reduced compared with controls in both active (p < 0.007) and inactive uveitis (p = 0.03). In inactive uveitis, VD is inversely related to the number of uveitis relapses (superficial capillary plexus: r = -0.694, p = 0.004; DCP: r = -0.541, p = 0.037) and it is significantly reduced in patients with a uveitis-free period ≥5 years compared with healthy controls (p < 0.038). CONCLUSIONS: Macular VD is reduced in Behçet patients with active and inactive uveitis, especially in DCP. In inactive uveitis, VD is inversely related to the number of ocular relapses and cannot be restored during time.

Epidemiology of Macular Edema in Uveitis.

PURPOSE: To describe the epidemiology of macular edema (ME) in patients with uveitis. METHODS: Review of articles listed on PubMed pertaining to uveitic ME. RESULTS: Reported rates of uveitic ME ranging from 20% to 70%, depending on the ancillary tests used (fundus examination, fluorescein angiography, optical coherence tomography). Macular edema might develop due to uveitis itself, or occur as an adverse effect of drugs taken for different diseases. It is more frequently observed in adults than in children, in chronic uveitis, and in intermediate uveitis. Males with ankylosing spondylitis are more prone to develop ME than females. Three patterns of uveitic ME are observed, either isolated or in combination: cystoid ME, the most frequently encountered pattern seen in up to 80% of cases, diffuse ME and serous retinal detachment. CONCLUSION: Older age, chronicity of uveitis and intermediate uveitis are risk factors for the development of ME in patients with uveitis.

Microvascular Retinal and Choroidal Changes in Retinal Vein Occlusion Analyzed by Two Different Optical Coherence Tomography Angiography Devices.

PURPOSE: To investigate retinal and choroidal microvascular changes and structural choroidal involvement in retinal vein occlusion (RVO). METHODS: Retrospective analysis of treatment-naïve macular edema secondary to RVO, studied by optical coherence tomography (OCT) and OCT angiography (OCTA), before and after the loading phase of intravitreal injections of ranibizumab (IVR-LP). OCTA was performed using two different devices: AngioVue RTVue XR Avanti (spectral-domain OCTA) and Zeiss PLEX® Elite 9000 (swept-source OCTA). RESULTS: 30 eyes of 30 consecutive patients (17 branch and 13 central RVO) were included. Central macular thickness and subfoveal choroidal thickness (SCT) were significantly reduced after IVR-LP (p < 0.001 and p = 0.046, respectively). 23 eyes were eligible for OCTA analysis. Baseline vessel density (VD) in deep capillary plexus (DCP) was significantly reduced in RVO eyes compared with fellow eyes (p = 0.03 and p = 0.002 for PLEX® Elite and AngioVue, respectively). After IVR-LP, no significant VD changes in any vascular layer was found. PLEX® Elite VD analysis showed significant differences in DCP between ischemic versus non-is-chemic eyes (p = 0.011). CONCLUSION: OCTA suggests a retinal vascular impairment of DCP but no involvement of choroid in RVO eyes. A greater baseline SCT could be due to a choroidal exudation. OCTA imaged with PLEX® Elite allowed to differentiate ischemic and non-ischemic patients at baseline.

Glutathione transferase P silencing promotes neuronal differentiation of retinal R28 cells.

Glutathione transferases (GSTs) play an important role in retinal pathophysiology. Within this family, the GSTP isoform is known as an endogenous regulator of cell survival and proliferation pathways and of cellular responses to oxidative stress. In the present study we silenced GSTP in R28 cells, a retinal precursor cell line with markers of both glial and neuronal origin, and obtained stable clones which were viable and, unexpectedly, characterized by a more neuronal phenotype. The degree of neuronal differentiation was inversely correlated with GSTP residual expression levels. The clone with the lowest expression of GSTP showed metabolic reprogramming, a more favorable redox status and, despite its neuronal phenotype, a sensitivity to glutamate and 4-hydroxynonenal toxicity comparable to that of control cells. Altogether, our evidence shows that near full depletion of GSTP in retinal precursor cells, triggers neuronal differentiation and prosurvival metabolic changes.

Patchy Chorioretinal Atrophy Changes at the Posterior Pole After Ranibizumab for Myopic Choroidal Neovascularization.

Purpose: To investigate the potential role of ranibizumab treatment on the development or enlargement of chorioretinal atrophy (CRA) at the posterior pole in eyes with myopic choroidal neovascularization (mCNV). Methods: This observational case series included patients having high myopia spherical equivalent refractive error ≥ -6.00 diopters, axial length (AxL) ≥ 26.0 mm in both eyes, and mCNV treated with ranibizumab 0.5 mg in one eye, who were retrospectively enrolled. Areas of CRA in treated and fellow eyes were measured on fundus autofluorescence images at baseline, 12, and 24 months. The CRA hypoautofluorescent lesions were divided in two groups: perilesional atrophy, corresponding to area around the mCNV, and patchy extralesional atrophy, corresponding to CRA between the temporal vascular arcades. Results: Thirty-six eyes of 18 patients were included. The mean perilesional CRA size significantly increased from baseline to 12 months (3.5 ± 10.6 mm2, P = 0.02) and 24 months (4.4 ± 11.7 mm2, P = 0.038) in the treated eye. In treated and not treated eyes, patchy extralesional CRA at the posterior pole increased significantly from baseline to 12 and 24 months follow-up. None of the fellow eyes developed mCNV. No significant relationship was found between the number of injections, AxL, age, and perilesional and patchy extralesional CRA in the treated and not treated eyes (P > 0.05). Conclusions: In eyes with pathologic myopia and mCNV, intravitreal injections of ranibizumab should not be considered as a contributing risk factor worsening the natural course of CRA, even though the risk of the perilesional CRA enlargement should be taken into account.

Levofloxacin and Tobramycin for Severe Bacterial Keratouveitis.

PURPOSE: To report on clinical features and outcome of severe bacterial keratouveitis. METHODS: Twenty patients with severe bacterial keratouveitis treated with topical tobramycin and levofloxacin and oral levofloxacin were included. Main outcome measures were ulcers location, bacterial isolates, risk factors, visual prognosis. RESULTS: Centrally located ulcer/abscess was present in 65% of patients. Contact lens (CL) wear was the most common risk factor (70%). Bacterial isolates were observed in 58% of patients, none resistant to tobramycin and levofloxacin. Pseudomonas aeruginosa was found in 47% of positive cases and in 64% of CL wearers. After therapy, the mean visual acuity improved significantly (p < 0.0001), particularly in contact lens wearers (p = 0.04) and in patients younger than 60 years old (p < 0.001). CONCLUSIONS: Pseudomonas aeruginosa is the most frequent cause of bacterial keratouveitis and CL wear the most common risk factor. Topical tobramycin and levofloxacin and oral levofloxacin are effective in the treatment of bacterial keratouveitis.

Vogt-Koyanagi-Harada disease after stapedotomy.

PURPOSE: To report on Vogt-Koyanagi-Harada disease that occurred after stapedotomy. METHODS: Case report. RESULTS: A 46-year-old woman developed bilateral choroiditis, papillitis, and serous retinal detachment 10 days after an uneventful surgical stapedotomy. The diagnosis was confirmed on the basis of the clinical features, fundus fluorescein angiography and optical coherence tomography findings, and a clinical course with subsequent involvement of the anterior segment, uveitis relapses with serous retinal detachment, and negative laboratory work-up for uveitis. CONCLUSIONS: Vogt-Koyanagi-Harada disease may appear after an uneventful surgical intervention of stapedotomy, suggesting that surgical trauma in the inner ear, a melanocyte-containing organ, may induce an inflammatory response within the eye.

Corneal and scleral dellen after an uneventful pterygium surgery and a febrile episode.

INTRODUCTION: We describe a patient with corneal and scleral dellen, which occurred after an uneventful pterygium excision without adjunctive therapy and a subsequent febrile episode. CASE REPORT: A 43-year-old woman presented with a history of recurrent irritation in her right eye and a diagnosis of pterygium. The pterygium was excised under local anesthesia with the bare scleral technique and without the use of antimetabolites. No complications occurred until 14 days after surgery when corneal and sclera dellen appeared; this was 2 days after a concomitant febrile episode (39°C). Tobramycin and dexamethasone eye drops given after surgery were withdrawn and topical lubricants and antibiotic ointment, in combination with oral L-amino acids, were administered along with eye patching. One week later, the corneal dellen had completely healed and, 4 weeks later, the thinned sclera appeared regularly thick and white in color. Three months after surgery, a small recurrent pterygium was diagnosed, which remained stable without signs of inflammation for additional 18 months. CONCLUSIONS: Corneal and scleral dellen might be a late complication of uneventful pterygium surgery without antimetabolites and a subsequent febrile episode.

Clinical features and prognosis of HLA B27-associated acute anterior uveitis in an Italian patient population.

PURPOSE: To report clinical features and prognosis of HLA B27 acute anterior uveitis. METHODS: 165 patients with recurrent acute anterior uveitis were divided into two groups: HLA B27-positive (group 1, 60 patients) and HLA B27-negative (group 2, 105 patients). A comparison between the two groups was performed. RESULTS: Unilateral involvement was higher in group 1 (p = .046), and more simultaneous bilateral cases occurred in group 2 (p = .004). Group 1 was more correlated to systemic diseases than group 2 (50 versus 17.1%, p < .001), particularly to ankylosing spondylitis (35 versus 3.8%, p < .001). Uveitis was diagnosed before spondylitis in 57% of patients. In groups 1 and 2 an immunosuppressive therapy was administered to 20 and 9.5% of patients but was exclusively given to control uveitis in 1.6 and in 2.8% of cases, respectively. CONCLUSIONS: A strong association between HLA B27 uveitis and ankylosing spondylitis was confirmed and usually uveitis preceded rheumatological involvement.