Comparing acromegalic patients to healthy controls with respect to intraocular pressure,central corneal thickness,and optic disc topography findings

Aims:

The aim was to compare the intraocular pressure (IOP), central corneal thickness (CCT), and optic disc topography findings of biochemically controlled acromegalic patients and the control group and to evaluate the effect of the duration of acromegaly and serum growth hormone and insulin-like growth factor-1 (IGF-1) levels on these ocular parameters.

Materials and Methods:

IOP measurement with Goldmann applanation tonometry, CCT measurement with ultrasonic pachymetry, and topographic analysis with Heidelberg retinal tomograph III were performed on 35 biochemically controlled acromegalic patients and 36 age- and gender-matched controls.

Results:

Mean IOP and CCT were 14.7 ± 2.9 mmHg and 559.5 ± 44.9 μm in the acromegaly patients and 13.0 ± 1.6 mmHg and 547.1 ± 26.7 μm in controls (P = 0.006 and P = 0.15, respectively). A significant moderate correlation was found between the duration of acromegaly and CCT (r = 0.391) and IOP (r = 0.367). Mean retinal nerve fiber layer (RNFL) thickness was significantly lower in the acromegalic patients (0.25 ± 0.05 mm) as compared to controls (0.31 ± 0.09 mm) (P = 0.01). A significant moderate correlation was detected between IGF-1 level and disc area (r = 0.362), cup area (r = 0.389) and cup volume (r = 0.491).

Conclusion:

Biochemically controlled acromegalic patients showed significantly higher CCT and IOP levels and lower RNFL thickness compared to healthy controls and the duration of disease was correlated with CCT and IOP levels.     

The relationship between corneal subbasal nerve density and corneal sensitivity in patients with Fuchs endothelial corneal dystrophy

Purpose:The aim of this study was to investigate the association between alterations in corneal subbasal nerve plexus and tactile corneal sensitivity in patients with Fuchs’ endothelial corneal dystrophy (FECD).Methods:This retrospective, cross-sectional study included 24 (10 M/14 F) patients with FECD and 25 age- and sex-matched (10 M/15 F) healthy subjects as controls. Subjects with FECD were classified as having early (grades 1 and 2) and late (grades 3 and 4) disease. All subjects underwent central corneal tactile sensitivity measurements with the Cochet–Bonnet esthesiometer (Luneau Ophthalmologie, Chartres, France) and subbasal nerve density evaluation using in vivo confocal microscopy (IVCM). Association between corneal nerve plexus density and corneal sensitivity alterations were evaluated using the Mann–Whitney U test and the Spearman correlation test.Results:Compared to healthy subjects (mean age = 60.4 ± 7.5 years), patients with FECD (mean age = 60.6 ± 8.0 years) had worse central corneal sensitivity scores (5.9 ± 0.1 cm vs. 4.2 ± 0.8 cm; P < 0.001), reduced corneal nerve fibers (3.4 ± 1.3 nerves/frame vs. 5.0 ± 0.9 nerves/frame; P < 0.001) and lower corneal subbasal nerve plexus densities (2229.4 ± 364.3 μm/mm² vs. 1901.6 ± 486.8 μm/mm²; P = 0.050). Patients with late stage FECD demonstrated lower subbasal nerve densities as compared to those with early disease (2204.3 ± 313.1 μm/mm² (range = 1523–2552 μm/mm²); 1397.1 ± 227.4 μm/mm² (range = 1120-1834 μm/mm²); P < 0.001). In the FECD group, subbasal nerve density was found to be directly correlated with corneal sensitivity scores (r = 0.457, P = 0.025).Conclusion:Progressive loss of the corneal subbasal nerve plexus appears to be a consistent feature of FECD. Reduction of the corneal nerve plexus parallels the decrease in corneal sensitivity in this patient population.     

Effect of fluidics on corneal endothelial cell density,central corneal thickness,and central macular thickness after phacoemulsification with torsional ultrasound

Aim:To study the relative effects of high and low fluidic parameters on endothelial cell density (ECD), central corneal thickness (CCT), and central macular thickness (CMT) after phacoemulsification with torsional ultrasound.Results:Cumulative dissipated energy was significantly higher in the low flow group (16.44 ± 9.07 vs. 11.74 ± 6.68; P = 0.002). No statistically significant difference was noted between the two groups in the ECD, CCT, CMT, or corrected distance visual acuity at the end of 6 weeks.Conclusions:No significant difference was noted in the postoperative outcome between high and low flow groups. Parameters can be modified to suit the surgeon''s preference, as both high and low flow parameters were found to have comparable postoperative outcomes.     

Evaluation of changes in corneal endothelium in chronic kidney disease

Purpose:Chronic kidney disease (CKD) is an emerging health problem worldwide. In CKD corneal endothelial changes also occur probably due to accumulation of inflammatory cytokines and increased multiple toxic products. The aim of this study was to analyze the effect of CKD on corneal endothelium and correlate the findings with severity of disease with help of noninvasive technique.Methods:The study comprised 75 eyes of 75 cases divided into three groups with group A comprising of CKD cases on dialysis, group B of nondialysis CKD cases, and group C of controls. Each group had 25 cases each of either sex and between 15–80 age groups. All patients were investigated for blood urea, serum creatinine, and blood sugar and underwent complete ophthalmic examination of both eyes along with wide-field specular microscopy examination.Results:The majority of patients (33.3%) belonged to age range of 61–70 years with male predominance and the most common cause of CKD was found to be diabetes with 17 (34%) cases. We found normal corneal endothelial cell density (ECD) with the mean ECD of 2364.52 ± 397.72 mm² in the dialysis group, 2467.8 ± 352.88 mm² in nondialysis group, and 2521.68 ± 250.26 mm² in the control group of patients. However, we found significant increase in coefficient of variation (CV) with 36 ± 5.8% in dialysis group, 37 ± 4.5% in nondialysis group and 32 ± 0.8% in controls (P = 0.001) and decreased hexagonality (Hx) with 47 ± 7.3% in dialysis group, 46 ± 4.7% in nondialysis group and 51 ± 6.7% in the controls (P = 0.031). This showed increased tendency of pleomorphism and polymegathism in corneal endothelial cells in CKD cases. No correlation was found between blood urea or serum creatinine levels with endothelial parameters in any group.Conclusion:CKD causes morphological changes like polymegathism and pleomorphism in corneal endothelium and hence these cases are more vulnerable and special care should be taken before any intraocular surgical procedure.     

Corneal endothelial morphology and central corneal thickness in type 2 diabetes mellitus patients

Purpose:This study aimed to examine the corneal endothelial morphology and thickness in patients with Type 2 diabetes mellitus (T2DM) and compare them with age and sex-matched nondiabetic controls.Methods:This hospital-based cross-sectional observational study was conducted in the ophthalmology department of a tertiary hospital consisting of 262 patients (131 with T2DM as cases and 131 without diabetes who served as controls). All patients underwent a comprehensive ocular examination including visual acuity, slit-lamp biomicroscopy, intraocular pressure measurement. Central corneal thickness (CCT), endothelial cell density (ECD), coefficient of variance (CV), and percentage of hexagonal cells (HEX) were compared between the cases and controls. Predictors of corneal endothelial dysfunctions were analyzed. Data analysis was done by Statistical Package for the Social Sciences (SPSS) version 17.0. Chi-square test, Fisher’s exact test, and Spearman’s rho correlation analysis were used as appropriate.Results:Patients with T2DM showed poorer visual acuity and higher intraocular pressure. As compared to controls, patients with T2DM had thicker CCT, lesser ECD, decreased HEX, and higher CV but the differences were statistically nonsignificant. HbA1c levels showed a significant positive correlation with CCT and CV and a negative correlation with ECD. Macroalbuminuria and higher albumin creatinine ratio was associated with an increase in CV in patients with T2DM.Conclusion:Our study showed that poorly controlled patients with T2DM and those with macroalbuminuria have corneal endothelial abnormalities.     

Comparison of ocular response analyzer parameters in primary open angle glaucoma and exfoliative glaucoma patients

Aim:

We sought to identify differences in the following measures of the ocular response analyser (ORA) between primary open angle glaucoma (POAG) and exfoliative glaucoma (EXG) patients: Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc) and Goldmann-correlated intraocular pressure (IOPg). We also sought to relate these ORA measures with central corneal thickness (CCT).

Materials and Methods:

This cross-sectional study was conducted on a total of 162 individuals (46 EXG patients, 66 POAG patients and 50 healthy subjects without any ocular and systemic disease). ORA measurements were performed, and a minimum of three readings were obtained from each test subject. Groups were compared according to their ORA parameters.

Results:

The mean CH levels of the EXG, POAG and healthy subjects were 7.6 ± 2.1, 9.1 ± 1.9 and 9.6 ± 1.7 mmHg, respectively. CH was significantly lower in the EXG patients compared to the other groups (P < 0.001). The mean CRF levels of the EXG, POAG and healthy subjects were 9.0 ± 2.0, 10.1 ± 1.7 and 9.8 ± 1.8mmHg, respectively. CRF levels in the eyes of the EXG patients were significantly lower compared to those of either the POAG patients (P = 0.005) or the healthy subjects (P = 0.03), but there was no significant difference in CRF levels between the POAG patients and the healthy subjects (P = 0.59). There was a significant positive correlation between CH and CCT in the EXG patients and healthy subjects (P < 0.001), but this correlation was not present in the POAG patients (P = 0.70).

Conclusions:

In this study, CH and CRF were found to be significantly reduced in the eyes of EXG patients compared to both the POAG patients and healthy subjects. Reduced CH in EXG patients might result in decreased support of peripapillary scleral structure and increased damage to the optic nerve during IOP increase.     

Function of the Retinal Pigment Epithelium in Patients With Neurofibromatosis Type 1

PurposeRetinal and choroidal abnormalities in neurofibromatosis type 1 (NF1) remain poorly studied. It has been reported, however, that the function of the retinal pigment epithelium (RPE) in NF1 was abnormal, with a supra-normal Arden ratio of the electro-oculogram (EOG). This study aims to evaluate the function of the RPE, using EOG, first in patients with NF1 compared to controls and second in patients with NF1 with choroidal abnormalities compared to patients with NF1 without choroidal abnormalities.MethodsThis prospective case-control study included 20 patients with NF1 (10 patients with choroidal abnormalities and 10 patients without) and 10 healthy patients, matched for age. A complete ophthalmologic assessment with multimodal imaging, an EOG, and a full-field electroretinogram were performed for each included patient. The main outcome measured was the EOG light peak (LP)/dark trough (DT) ratio.ResultsThe LP/DT ratio was 3.02 ± 0.52 in patients with NF1 and 2.63 ± 0.31 in controls (P = 0.02). DT values were significantly lower in patients with NF1 than in controls (240 vs. 325 µV, P = 0.02), while light peak values were not significantly different (P = 0.26). No difference was found for peak latencies. No significant correlation between the surface and number of choroidal abnormalities and EOG parameters was demonstrated.ConclusionsThis study confirms the dysfunction of the RPE in patients with NF1, involving a lower DT and a corresponding higher LP/DT ratio. We hypothesize that this pattern may be due to a dysregulation of the melanocytogenesis, inducing a disruption in Ca2⁺ ion flux and an abnormal polarization of the RPE.     

To compare central corneal thickness measurements obtained by Pentacam with those obtained by IOLMaster 700, Cirrus anterior segment optical coherence tomography and Tomey specular microscopy in normal healthy eyes

Purpose:To compare central corneal thickness measurements obtained by Pentacam with those obtained by IOL Master 700, Cirrus Anterior segment optical coherence tomography and Tomey Specular microscopy in normal healthy eyes.Methods:Two hundred and six eyes of healthy subjects were included in the study. Each subject was assessed by four different methods of measuring central corneal thickness using Pentacam, IOL Master 700, Cirrus AS-OCT and Tomey Specular microscopy by a single examiner.Results:The mean CCT [± standard deviation (SD)] for Pentacam, IOL Master 700, Cirrus AS-OCT and Tomey Specular microscopy were Pentacam (Oculus), AS-OCT (Cirrus), IOL Master 700 and Specular microscopy (Tomey) were 523.75 (±27.75), 525.29 (±28.81),517.13 (±28.43) and 512.82 (±27.60) μm, respectively. All the means were significantly different from one another (P < 0.000). The differences between pairs of mean central corneal thickness (CCT) for Pentacam and IOL Master, Pentacam and anterior segment- optical coherence tomography (AS-OCT), and Pentacam and Specular microscopy are statistically significant. Bland–Altman plots showed that pentacam and IOL Master 700 have the closest agreement, followed by AS-OCT. Specular microscopy was found to have the poorest agreement with Pentacam.Conclusion:We found that CCT measurements of Pentacam did not correlate with measurements of IOL Master, or AS-OCT or Specular microscopy. In clinical practice, the devices analyzed should not be used interchangeably due to low agreement regarding CCT values.     

Topical cyclosporine to control ocular surface disease in patients with chronic glaucoma after long-term usage of topical ocular hypotensive medications

Purpose

To evaluate changes in ocular surface and central corneal sub-basal nerve fiber layer (SBNFL) after topical cyclosporin therapy in chronic glaucoma patients on long-term topical antiglaucoma therapy.

Methods

A prospective comparative study of ocular surface evaluation of chronic glaucoma patients on long-term topical therapy treated concurrently with a topical cyclosporine 0.05% twice daily for 6 months and controls was done. The study parameters evaluated at recruitment and at the 6-month follow-up included details of topical antiglaucoma medications, visual acuity, intraocular pressure, ocular surface evaluation parameters (TBUT, Schirmers I, ocular surface staining scores and ocular surface disease (OSD) index score (OSDI)), central corneal sensation (Cochet Bonnett aesthesiometer), and central confocal microscopy to study the SBNFL density (SBNFLD).

Results

Thirty-two eyes of 16 patients with chronic glaucoma and 30 eyes of 15 normal subjects as controls were studied. Mean TBUT, pre/post CsA treatment was 8.67±3.01/12.24±1.83 s (P=0.007). Mean conjunctival/corneal staining scores pre/post CsA treatment were 3.38±1.93/1.50±0.718 (P=0.00) /5.19±1.82/1.81±0.78 (P=0.098), respectively. Mean OSDI pre/post CsA treatment scores were 30.63±14.61/14.76±6.06 (P=0.007). Mean corneal sensations scores pre/post CsA treatment were 4.64±0.46/4.94±0.39 (P=0.002). Central corneal SBNFLD pre and post CsA treatment was 8811.35±2985.29/10335.13±4092.064 μm/mm² (P=0.0001).

Conclusions

Schirmer''s test, ocular surface staining scores, OSDI, corneal sensations, and corneal SBNFLD showed a statistically significant improvement following a 6-month concurrent topical CsA therapy.     

Effect of Head Position and Tube Entry on Corneal Endothelial Cells in Patients with Glaucoma Drainage Implants: A Cross-sectional Study

PurposeTo investigate the effect of head tilt on the tube position of the Ahmed glaucoma valve (AGV) implanted in patients with glaucoma and to assess how the head tilt-induced alterations of tube parameters and the level of tube entry influence corneal endothelial cell density (ECD).MethodsA total of 29 eyes of 26 patients with AGV implantation were included. Tube-cornea distance, tube-cornea angle, and intracameral tube length were measured using anterior segment optical coherence tomography in three different head positions (neutral, 30° temporalward tilt, and 30° nasalward tilt). The tube entry was assessed using static gonioscopy. ECD was measured using specular microscopy before and after surgery.ResultsThe mean tube-cornea distance, tube-cornea angle, and intracameral tube length (neutral: 0.87 ± 0.39 mm, 30.56 ± 5.89˚, and 3.10 ± 0.82 mm, respectively) decreased with head tilts (temporalward: 0.82 ± 0.39 mm, 29.27 ± 5.82˚, and 3.04 ± 0.82 mm, respectively; nasalward: 0.83 ± 0.40 mm, 29.61 ± 6.04˚, and 3.05 ± 0.81 mm, respectively; all p < 0.01). The multivariate analyses found age and the tube insertion level to be associated with postoperative changes in the central ECD (p = 0.039 and 0.013, respectively), and the postoperative follow-up period and tube insertion level to be associated with the difference between the inferonasal and superotemporal ECDs (p = 0.034 and 0.007, respectively).ConclusionsMild alterations of head positions induced changes in the intracameral tube positions of AGV implants; nevertheless, it did not significantly affect ECD loss. However, the eyes with tubes inserted anteriorly to Schwalbe’s line may be more susceptible to corneal ECD loss.     

Effects of water drinking on corneal biomechanics: The association with intraocular pressure changes

Purpose:We aimed to assess the impact of drinking water (500 and 1000 mL) on corneal biomechanics and determine the level of association between changes in intraocular pressure and variations in the different biomechanical properties of the cornea.Methods:A total of 39 healthy young adults ingested either 1000 mL (n = 21) or 500 mL (n = 18) of tap water in 5 min. The CorVis ST system was used to assess corneal biomechanics at baseline and at 15, 30, and 45 min after water ingestion.Results:Water drinking induced statistically significant changes in the deformation amplitude (P < 0.001, η² = 0.166), highest concavity time (P = 0.012, η² = 0.093), peak distance (P < 0.001, η² = 0.171), time and velocity of the first applanation (P < 0.001, η² = 0.288 and P = 0.016, η² = 0.087, respectively), and time and velocity of the second applanation (P = 0.030, η² = 0.074 and P = 0.001, η² = 0.132, respectively), being independent of the amount of water ingested (P > 0.05 in all cases). There were significant associations between changes in intraocular pressure and some parameters of corneal biomechanicsConclusion:Small variations in whole-body hydration status alter different biomechanical properties of the cornea, with these changes being associated with intraocular pressure levels. These findings indicate that whole-body hydration status can be considered for the diagnosis and management of different ocular conditions.     

Comparability and repeatability of pachymetry in keratoconus using four noncontact techniques

Purpose:To compare and determine the repeatability of central corneal thickness (CCT) measurements using four noncontact pachymetry instruments in eyes with keratoconus.Results:Fifty eyes of 25 participants were analyzed in this study. All measurement methods correlated well with each other (r > 0.9, P < 0.001). Mean ± standard deviation CCT measured by HHSD-OCT, Orbscan IIz, SS-OCT, and Pentacam was 462 ± 41 μm, 458 ± 41 μm, 454 ± 40 μm, and 447 ± 42 μm, respectively. While the HHSD-OCT over-estimated the CCT (P < 0.001), there was a good correlation between the measurements obtained from the other three devices. However, the numerical difference was high and this trend was seen in all the paired comparisons.Conclusions:Though the measurements by different devices correlated well, the numerical agreement may be inadequate for their interchangeable use in clinical practice.     

Assessing the role of systemic inflammation in the etiopathogenesis of advanced stage keratoconus

Purpose:It was aimed to compare the levels of inflammation-related parameters, such as neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR), in patients with advanced keratoconus (KC) and healthy controls. Also, we evaluated the relationships between these parameters and several corneal topography values used in the KC diagnostic index.Methods:Forty patients with advanced and 40 healthy volunteers were included in this study. In the KC group, 20 patients were nonprogressive KC and 20 patients were progressive KC. In all participating individuals, we evaluated detailed ophthalmologic examination findings and complete blood count data, while corneal topographic measurements were also recorded in patients with KC.Results:The mean NLR value was 2.3 ± 1.19 in the progressive KC group; nonprogressive KC values were 1.99 ± 1.69 and 1.81 ± 0.72 in the control group. Mean PLR value was 113.24 ± 48.44 in the progressive KC group, nonprogressive KC values were 96.47 ± 31.04 and 104.09 ± 35.14 in the control group. No statistically significant difference was found between patients with progressive KC, nonprogressive KC, and healthy volunteers in terms of mean NLR and PLR values (P > 0.05). NLR values were found to demonstrate significant positive correlations with the corneal topography parameters, Symmetry Index front (r = 0.278, P = 0.025), KC Vertex front (r = 0.247, P = 0.048), and Baiocchi Calossi Versaci front (r = 0.273, P = 0.028); there was no significant relationship between corneal topography parameters and PLR values.Conclusion:Although there was no significant difference between the progressive KC, nonprogressive KC, and control groups in inflammation parameters such as NLR and PLR, a positive correlation was observed between the NLR value and some corneal topography findings used in the diagnosis of KC. The role of inflammation in the etiology of KC can be better understood by clinical studies and laboratory tests conducted with prospective studies involving a higher number of patients.     

Comparison of central corneal thickness using non-contact tono-pachymeter (Tonopachy) with ultrasound pachymetry in normal children and in children with refractive error

Purpose:To compare the central corneal thickness (CCT) measured by non-contact tono-pachymeter [Tonopachy (TP)] with the gold standard ultrasound pachymetry (UP) in normal children and in children with refractive error.Methods:This cross-sectional study involved 95 normal children (190 eyes) and 123 children with refractive error (246 eyes), a total of 218 children (436 eyes) aged 7-15 years. After refraction and complete ophthalmic evaluation, axial length was measured with IOLMaster 700, CCT was measured with TP followed by UP. The correlation between the CCT measurements obtained with the two methods was analysed by Intraclass correlation coefficient (ICC) and the limits of agreement were assessed with Bland-Altman analysis plot.Results:Mean CCT measured with TP was 537.46 ± 36.41 μm and by UP was 537.17 ± 39.80 μm in normal children (P = 0.79) and in refractive error group, the mean CCT was 533.50 ± 34.91 μm by TP and 531.60 ± 36.30 μm by UP (P = 0.04). The 95% limits of agreement between TP and UP ranged from -19.2 to + 21.6 μm (mean = 1.20) for total children, -20.8 to + 21.4 μm (mean = 0.29) for normal group and -18.0 to + 21.8 μm (mean = 1.90) for refractive error group. ICC for CCT measurement between TP and UP was 0.980 for total children and refractive error group and 0.981 for normal group.Conclusion:The CCT measurement obtained by TP showed an excellent agreement with UP. Hence non-contact TP can be used to assess CCT in children above seven years of age.     

Early Identification of Retinal Neuropathy in Subclinical Diabetic Eyes by Reduced Birefringence of the Peripapillary Retinal Nerve Fiber Layer

PurposeTo study birefringence of the peripapillary retinal nerve fiber layer (RNFL) of diabetic eyes with no clinical signs of diabetic retinopathy (DR) or mild to moderate DR stages using spectral-domain polarization-sensitive (PS) optical coherence tomography (OCT).MethodsIn this observational pilot study, circular PS-OCT scans centered on the optic nerve head were recorded in prospectively recruited diabetic and age-matched healthy eyes. From averaged circumpapillary intensity and retardation tomograms plots of RNFL birefringence were obtained by a linear fit of retardation versus depth within the RNFL tissue for each A-scan position and mean birefringence values for RNFL calculated. Spectral-domain OCT imaging (Heidelberg Engineering) was performed to assess peripapillary RNFL thickness and macular ganglion cell complex (GCC).ResultsOut of 70 eyes of 43 diabetic patients (mean ± SD age: 50.86 ± 15.71) 36 showed no signs of DR, 17 mild and 17 moderate nonproliferative DR with no diabetic macular edema. Thirty-four eyes of 34 healthy subjects (53.21 ± 13.88 years) served as controls. Compared with healthy controls (0.143° ± 0.014°/µm) mean total birefringence of peripapillary RNFL was significantly reduced in subclinical diabetic eyes (0.131° ± 0.014°/µm; P = 0.0033), as well as in mild to moderate DR stages (0.125° ± 0.018°/µm, P < 0.0001) with borderline statistically significant differences between diabetic patients (P = 0.0049). Mean birefringence values were significantly lower in inferior compared with superior RNFL sectors (P < 0.0001) of diabetic eyes with no such difference detected in the healthy control group.ConclusionsWe identified evidence of early neuroretinal alteration in diabetic eyes through reduced peripapillary RNFL birefringence assessed by PS-OCT occurring before appearance of clinical microvascular lesions or GCC alterations.     

Reach Kinematics During Binocular Viewing in 7- to 12-Year-Old Children With Strabismus

PurposeEye–hand coordination is essential for normal development and learning. Discordant binocular experience from childhood strabismus results in sensory and ocular motor impairments that can affect eye–hand coordination. We assessed reach kinematics during visually guided reaching in children treated for strabismus compared with controls.MethodsThirty-six children aged 7 to 12 years diagnosed with esotropia, a form of strabismus, and a group of 35 age-similar control children were enrolled. Reach movements during visually guided reaching were recorded using the LEAP Motion Controller. While viewing binocularly, children reached out and touched a small dot that appeared randomly in one of four locations (±5° or ±10°). Kinematic measures were reach reaction time, total reach duration, peak velocity, acceleration duration, and deceleration duration. Touch accuracy and factors associated with impaired reach kinematics were evaluated.ResultsStrabismic children had longer total reach duration (545 ± 60 ms vs. 504 ± 43 ms; P = 0.002), had longer deceleration duration (343 ± 54 ms vs. 312 ± 45 ms; P = 0.010), and were less accurate (93% ± 6% vs. 96% ± 5%, P = 0.007) than controls. No differences were found for reach reaction time, peak velocity, or acceleration duration (all Ps ≥ 0.197). Binocular dysfunction was more related to slow reaching than amblyopic eye visual acuity.ConclusionsStrabismus affects visually guided reaching in children, with slower reaching in the final approach and reduced endpoint accuracy. Binocular dysfunction was predictive of slow reaching. Unlike strabismic adults who show longer acceleration duration, longer deceleration in the final approach in strabismic children indicates a difference in control that could be due to reduced ability to use visual feedback.     

Corneal and corneal epithelial thickness distribution characteristics in healthy North Indian eyes using spectral domain optical coherence tomography

Purpose:To determine the pattern of corneal thickness and epithelial thickness distribution in healthy North Indian eyes by using spectral domain optical coherence tomography (SD-OCT).Methods:The observational study measured total corneal and epithelial thickness in the central 2 mm zone and eight sectors each in paracentral 2–5 mm (ring 1) and midperipheral 5–7 mm (ring 2) zones on SD-OCT.Results:The study included 67 eyes of 67 subjects with a male:female ratio of 32:35 and mean age of 25.04 ± 4.54 years. The mean central corneal and epithelial thicknesses were 505.97 ± 30.12 mm and 60.48 ± 8.37 mm, respectively. The epithelium of inferior and infero-nasal sectors in ring 1 and inferior sector in ring 2 was significantly thicker than the radially opposite sectors of the respective rings (P = 0.001; P = 0.01 and P = 0.02, respectively). Sector-wise analysis did not reveal any significant correlation between the total corneal thickness and epithelial thickness (all P > 0.05) except in the outer superior sector where there was a weak positive correlation (r = 0.28, P = 0.02). Central epithelial thickness in males (60.59 ± 9.28 mm) and females (60.37 ± 7.58 mm) was comparable (P = 0.91). Pachymetry was thinnest in the inferior, inferonasal, and inferotemporal sectors in 44.79% of eyes (n = 30), while thinnest epithelium was seen in the superior, superonasal, and superotemporal quadrants in 50.75% of eyes (n = 34)Conclusion:The epithelial thickness distribution in this sample of topographically normal healthy North Indian eyes was nonuniform and independent of the underlying corneal thickness. Epithelium was thinner in the superior cornea, whereas total corneal thickness was minimum in the inferior part.     

Activation of Conjunctiva-Associated Lymphoid Tissue in Patients With Infectious Keratitis Using In Vivo Confocal Microscopy

PurposeWe aimed to evaluate activation of conjunctiva-associated lymphoid tissue (CALT) in patients with keratitis using in vivo confocal microscopy (IVCM) and conjunctival impression cytology (CIC).MethodsIn addition to anterior segment photography and corneal fluorescein staining, IVCM revealed the palpebral conjunctiva in all subjects, and CIC and immunofluorescence staining were performed.ResultsDiffuse lymphoid tissue cell density in the eyes of patients with keratitis was significantly greater compared with healthy volunteers (P < 0.001). Similar trends were found in perifollicular lymphocyte density (P < 0.001), follicular density (P = 0.029), follicular center reflection intensity (P = 0.011), and follicular area (P < 0.001). Immunofluorescence staining showed that the proportions of CD4⁺ (61.7% ± 8.0% vs. 17.3% ± 10.2%, respectively, P < 0.001) and CD8⁺ (46.9% ± 10.0% vs. 19.6% ± 11.5%, respectively, P < 0.001) cells in patients with keratitis was greater compared with healthy volunteers. Interestingly, we also observed changes in the contralateral eye in subjects with keratitis.ConclusionsOur research suggests that CALT, as an ocular immune structure, is activated and plays an important role in the pathogenesis of keratitis. This has been overlooked previously. CALT is also active in the contralateral eye of subjects with keratitis.     

Semilunar sign of cornea: A multimodal analysis of the posterior corneal opacity in non-infectious anterior scleritis

Purpose:To analyze the morphological outcomes of the posterior corneal opacity or “semilunar sign” in noninfectious anterior scleritis using multimodal imaging.Methods:This was a prospective observational case series. Patients with anterior scleritis from January 2018 to January 2019 were included. Clinical and demographic data were collected. Posterior cornea was visualized using the digital slit lamp photography (Elite, mega digital vision), spectral domain optical coherence tomography (MS39), and specular count analyzer (EM-3000). “Semilunar sign” was defined by the (1) presence of posterior corneal opacity, (2) concave semilunar pattern, (3) absence of blood vessels, and (4) normal anterior cornea. Incidence, clinical characteristics and significance, correlation with Mantoux sensitivity, and role of multimodal valuation were assessed.Results:Overall 76 eyes of 72 patients were recruited with anterior scleritis. Fifteen eyes of 11 patients (15.3%) presented with semilunar sign. The scleritis was both nonnecrotizing (n = 8) and necrotizing (n = 7). The semilunar configuration appeared as isolated (n = 9) and continuous lesion (n = 6). The extent was directly related to the scleral disease extent (P = 0.002). The mean thickness measured 212.5 ± 129.3 mm. The mean central endothelial cell density (ECD) was 2540.8 ± 351.7 cells/mm², which was significantly higher than the involved peripheral cornea (P = 0.05). The mean surface area of the semilunar sign was 7.7 ± 5.2 mm². There was no significant correlation between the opacity thickness and the best-corrected visual acuity (P = 0.895, r = −0.39), ECD (P = 0.52, r = −0.188), and Mantoux (P = 0.696, r =− 0.142)Conclusion:Corneal semilunar sign of scleritis affected the peripheral cornea and caused no functional abnormality in early presentation. Multimodal analysis can aid in clinical assessment and severity.     

The Macular Choriocapillaris Flow in Glaucoma and Within-Day Fluctuations: An Optical Coherence Tomography Angiography Study

PurposeTo assess quantitatively the choriocapillaris (CC) perfusion area in the macular area of healthy eyes, eyes with primary open-angle glaucoma, and eyes with ocular hypertension using optical coherence tomography angiography (OCTA).MethodsA consecutive series of healthy individuals and patients with glaucoma and ocular hypertension were recruited prospectively in this single-center, cross-sectional study based in Milan, Italy. OCTA was performed in the morning and evening, along with a complete ophthalmologic examination. Macular superficial capillary plexus vessel density (SCP-VD) and the thicknesses of the retina and ganglion cell complex (GCC), as well as their fluctuations, were investigated.ResultsThirty-nine eyes from 24 individuals with glaucoma (mean age = 58.79 ± 6 years), 43 eyes from 27 individuals with ocular hypertension (59.19 ± 6 years), and 54 eyes from 35 controls (58.27 ± 6 years) were enrolled. The mean CC perfusion area values were not significantly different among the three groups in the morning or evening (P ≥ 0.47). In contrast, SCP-VD, retinal thickness, and GCC thickness were statistically different among the groups (P ≤ 0.016), except for the foveal SCP-VD (P ≥ 0.19) and the evening foveal thickness (P = 0.57). Diurnal changes in the CC perfusion area, SCP-VD, retinal thickness, and GCC thickness were not statistically significant (P ≥ 0.16). Systemic hypertension, sex, age, axial length, and diurnal changes in intraocular pressure were not significantly associated with morning or evening measurements, or with diurnal fluctuations (P ≥ 0.07).ConclusionsThe macular CC flow perfusion area appears unaffected in eyes with primary open-angle glaucoma. No significant diurnal changes were observed in any of the parameters investigated.