Anterior Segment Optical Coherence Tomography Angiography and Optical Coherence Tomography in the Evaluation of Episcleritis and Scleritis.

Purpose: To evaluate the feasibility of using anterior segment optical coherence tomography (AS-OCT) and AS-OCT angiography (AS-OCTA) in assessing patients with episcleritis and scleritis.Methods: Degree of vascularity [vessel density index (VDI)], measured with AS-OCTA, and sclera thickness [conjunctiva epithelium (CE), conjunctiva/episclera complex (CEC), and episclera/sclera complex (ESC)], measured with AS-OCT were compared.Results: A total of 37 eyes (13 episcleritis, 11 scleritis, 13 controls) were analyzed. VDI was lowest for controls for the various tissue depths (p < .001). Episcleritis versus scleritis revealed a significant difference in VDI at ESC (38.1 ± 11.4% vs 46.4 ± 6.4%; p = .03). Mean sclera thickness was lower in controls for CE (p < .001), CEC (p < .001) but not for ESC (p = .54).Conclusions: The degree of vascularity and tissue thickness were different between episcleritis, scleritis and controls. AS-OCTA and AS-OCT may potentially be useful in evaluating patients with scleral inflammation.

In Vivo Confocal Microscopy Morphologic Features and Cyst Density in Acanthamoeba Keratitis.

PURPOSE: To correlate in vivo confocal microscopy morphologic features (IVCM-MF) and Acanthamoeba cyst density (ACD) with final best-corrected visual acuity (BCVA) in Acanthamoeba keratitis (AK). DESIGN: Retrospective cohort study. METHODS: Patient demographics, treatment outcome, and corresponding IVCM-MF performed at the acute stage of infection were analyzed. Inclusion criteria were microbiological positive AK cases seen at Moorfields Eye Hospital between February 2013 and October 2017. Statistical significance was assessed by multinomial regression and multiple linear regression analysis. Main outcome measure was final BCVA. RESULTS: A total of 157 eyes (157 patients) had AK. Absence of single-file round/ovoid objects was associated with a BCVA of 6/36 to 6/9 (odds ratio [OR] 8.13; 95% confidence interval [CI], 1.55-42.56, P = .013) and ≥6/6 (OR 10.50; 95% CI, 2.12-51.92, P = .004) when compared to no perception of light to 6/60. Absence of rod/spindle objects was associated with a BCVA of ≥6/6 (OR 4.55; 95% CI, 1.01-20.45, P = .048). Deep stromal/ring infiltrate was associated with single-file round/ovoid objects (OR 7.78; 95% CI, 2.69-22.35, P < .001), rod/spindle objects (OR 7.05; 95% CI, 2.11-23.59, P = .002), and binary round/ovoid objects (OR 3.45; 95% CI, 1.17-10.14, P = .024). There was a positive association between ACD and treatment duration (ß = 0.14, P = .049), number of IVCM-MF (ß = 0.34, P = .021), and clusters of round/ovoid objects (ß = 0.29, P = .002). CONCLUSIONS: Specific IVCM-MF correlate with ACD and clinical staging of disease, and are prognostic indicators for a poorer visual outcome.

Changes in corneal aesthesiometry and the sub-basal nerve plexus in benign essential blepharospasm.

BACKGROUND: The aetiology of blepharospasm remains unclear. There is evidence that the afferent pathway is important, but this area remains under-researched. AIM: To explore the hypothesis that the afferent arm of the blink reflex is abnormal in blepharospasm by assessing a range of measures of corneal sensory function. METHODS: In this prospective case-control study, 21 patients with blepharospasm and 21 age-matched and gender-matched controls completed the Ocular Surface Disease Index questionnaire and underwent the following assessments: tear osmolarity, Shirmer test, tear-film break up time, corneal and conjunctival vital staining, meibomian gland dysfunction, corneal aesthesiometry and confocal microscopy. RESULTS: Corneal sensitivity was significantly lower in patients with blepharospasm than in controls (right eyes p=0.009; left eyes p=0.009, paired t test). The median number of main nerve trunks was lower for patients with blepharospasm than for controls, and this was statistically significant at the 5% level (p=0.04, paired t test). Mean nerve density, median number of nerve branches and median total number of nerves were lower for blepharospasm cases than controls, but this did not reach statistical significance. Tortuosity was greater for blepharospasm cases than controls, but this was not statistically significant. CONCLUSIONS: Blepharospasm is associated with reduced corneal aesthesiometry and a tendency towards a reduced number of nerves in the sub-basal plexus, implying an impairment in corticosensory processing, possibly a defect of the sensorimotor gating mechanism resulting in a loss of inhibition of the blink reflex.

Evaluation of iris and iridociliary body lesions with anterior segment optical coherence tomography versus ultrasound B-scan.

AIMS: To compare anterior segment optical coherence tomography (AS-OCT) with ultrasound B-scan (USB) in evaluating iris and iridociliary body lesions. METHODS: Image features and resolution comparison between AS-OCT and USB in 126 patients (126 eyes) presenting with iris or iridociliary body lesion. Bland-Altman plots were generated to assess the level of agreement between the two techniques. RESULTS: The three most common diagnoses were iris naevi (62 (49.2%)), iris pigment epithelial cysts (23 (18.3%)) and iris melanoma (11 (8.7%)). Image feature comparison for USB was better than AS-OCT in visualising all tumour margins (81 (64.3%) vs 59 (46.8%)), posterior tumour margin (54 (42.9%) vs 16 (12.7%)) and producing less posterior shadowing (121 (96%) vs 43 (34.1%)). Image resolution comparison revealed USB to be slightly better for resolving the overall tumour (45 (35.7%) vs 43 (34.1%)) and posterior tumour surface (70 (55.6%) vs 32 (25.4%)) but AS-OCT was better for resolving the anterior (62 (49.2%) vs 4 (3.2%)) and lateral tumour surface (62 (49.2%) vs 31 (24.6%)). Comparing the three most common diagnoses, USB was better for visualising iris pigment epithelial cysts (12 (52.2%) vs 2 (8.7%)) and iris melanoma (7 (63.6%) vs 1 (9.1%)) but AS-OCT was better (28 (45.2%) vs 15 (24.2%)) for visualising iris naevi. Bland-Altman plots showed good agreement between the two techniques for lesions smaller than 3 mm in base and 2 mm in elevation. CONCLUSIONS: AS-OCT is superior to USB for imaging small lesions pertaining to the anterior iris but USB is better for imaging larger iris lesions with posterior or ciliary body extension.

In vivo confocal microscopy findings in central toxic keratopathy.

Central toxic keratopathy is an uncommon complication after laser in situ keratomileusis. We report the confocal microscopy findings in a case of central toxic keratopathy that confirm loss of keratocytes from the corneal stromal bed in the acute phase, with gradual repopulation over the following year.

In vivo confocal microscopy of bleb-like disorder in epithelial basement membrane dystrophy.

PURPOSE: To report the confocal microscopic appearance of bleb-like disorder in epithelial basement membrane dystrophy (EBMD). METHODS: Two subjects with bleb-like disorder in EBMD were examined with slit-lamp biomicroscopy and in vivo confocal microscopy using the Heidelberg Retina Tomograph II/Rostock Cornea Module. A sample obtained from epithelial debridement from 1 subject provided histologic correlation. RESULTS: Confocal microscopy showed areas of circular and irregular hyporeflectivity ranging from 30 to 150 µm in diameter at the level of the basal epithelium and Bowman layer, with apparent fragmentation of the subbasal nerve plexus. The stroma, Descemet membrane, and corneal endothelium appeared normal. The epithelial biopsy results revealed subepithelial deposits of material anterior to the Bowman layer that stained positively with periodic acid-Schiff (PAS). CONCLUSIONS: This clinicopathologic correlation of bleb-like disorder in EBMD using confocal microscopy demonstrates the distinctive morphology of this disorder. It provides additional information to help with the interpretation of confocal images.

Quality of life in high myopia before and after implantable Collamer lens implantation.

PURPOSE: To examine changes in vision-related quality of life after implantable Collamer lens (ICL) implantation for the correction of myopia. DESIGN: Prospective, interventional, consecutive case series. PARTICIPANTS: We included 34 consecutive patients (68% female; mean age, 37 years [range, 23-49]) with preoperative myopia (mean ± standard deviation [SD] refraction spherical equivalent, -11.0 ± 3.12). INTERVENTION: Bilateral ICL implantation. MAIN OUTCOME MEASURES: Quality of life Impact of Refractive Correction (QIRC) score. RESULTS: The median postoperative interval before questionnaire administration was 4 months (range, 3-7). The QIRC scores were significantly higher postoperatively (preoperative QIRC score [mean ± SD], 40.45 ± 4.83; postoperative QIRC score 53.79 ± 5.60; P < 0.001), with significant improvements (P<0.01) for 14 of 19 items. Nineteen (58%) patients reported a worsening in night vision symptoms (mostly nonspecific glare and halo or arc effects) after surgery, but overall levels of satisfaction were high; 88% were either satisfied or very satisfied with the results of surgery. No patients reported overall dissatisfaction. In free text responses, 11 patients (32%) described ICL implantation as life changing or wished that they had opted for the surgery sooner. CONCLUSIONS: Implantation of an ICL for myopia is associated with significant improvements in quality of life. Any dissatisfaction with the procedure largely relates to night vision symptoms, which are common in the early postoperative period.

Diagnostic accuracy of microbial keratitis with in vivo scanning laser confocal microscopy.

AIMS: To determine the accuracy of diagnosing microbial keratitis by masked medical and non-medical observers using the Heidelberg Retina Tomograph II/Rostock Cornea Module in vivo confocal microscope. METHODS: Confocal images were selected for 62 eyes with culture- or biopsy-proven infections. The cases comprised 26 Acanthamoeba, 12 fungus, three Microsporidia, two Nocardia and 19 bacterial infections (controls). The reference standard for comparison was a positive tissue diagnosis. These images were assessed on two separate occasions by four observers who were masked to the tissue diagnosis. Diagnostic accuracy indices, kappa statistic and percentage agreement values were calculated. The Spearman correlation coefficient (r(s)) was calculated for the number of correct diagnoses versus duration of disease. RESULTS: The highest sensitivity and specificity values were 55.8% and 84.2%, respectively, and the lowest sensitivity and specificity values were 27.9% and 42.1%, respectively. The highest positive and lowest negative likelihood ratios were 2.94 and 0.59, respectively. Agreement values were: fair to moderate (kappa 0.22-0.44) for reference standard versus observer diagnosis, moderate to good in intraobserver variability (repeatability, kappa 0.56-0.88) and poor to moderate in interobserver variability (reproducibility, kappa 0.15-0.47). The correct diagnosis was associated with duration of disease for Acanthamoeba keratitis (r(s)=0.60, p=0.001). CONCLUSIONS: The diagnostic accuracy of microbial keratitis by confocal microscopy is dependent on observer experience. Intraobserver repeatability was better than interobserver reproducibility. Difficulty in distinguishing host cells from pathogenic organisms limits the value of confocal microscopy as a stand-alone tool in diagnosing microbial keratitis.

Presumed corneal argyrosis from occlusive soft contact lenses: a case report.

PURPOSE: To report a case of presumed corneal argyrosis associated with sliver nitrate-coated cosmetic soft contact lens wear. METHODS: A 67-year-old woman wore silver nitrate-coated occlusive soft lenses for 17 years for the management of intractable diplopia. Slit-lamp examination revealed a diffuse blue-gray deposit that was characteristic of corneal argyrosis just anterior to Descemet membrane. Confocal microscopy, anterior segment optical coherence tomography, and noncontact specular microscopy were performed. RESULTS: Confocal microscopy showed hyperreflective granules in Bowman layer, deep stroma, and Descemet membrane. The granules were below the resolution of anterior segment optical coherence tomography. Confocal and specular microscopy showed an abnormal reflection from the region of Descemet membrane. Central corneal endothelial cell density was 2560 cells per square millimeter. CONCLUSION: Presumed corneal argyrosis can occur after long-term use of silver nitrate-coated contact lenses.

Contact lens fitting following unsuccessful refractive surgery.

A retrospective review of case notes of consecutive patients referred to a contact lens clinic after unsuccessful refractive surgery was carried out to determine the success of contact lens fitting. The main outcome variables in determining success were visual improvement, contact lens tolerance, fitting characteristics and wearing time. Thirteen eyes were fitted with conventional rigid gas permeable (CRGP), 10 with soft and 19 with reverse geometry rigid gas permeable contact lenses (RVG). The mean spectacle visual acuity (VA) was 6/9 (20/30) [range: 6/24 (20/80) to 6/5 (20/15)] and the mean VA after contact lens fitting was 6/6 (20/20) [range: 6/18 (20/60) to 6/5 (20/15)]. Of the 42 eyes, the contact lens VA was better than spectacle acuity in 25 (59.5%) eyes, equal in 14 (33.3%) and worse in three (7.1%). A total of 33 (78.6%) eyes were still wearing their lenses at the last visit. Contact lenses can be a valuable method of managing poor VA after refractive surgery.