Evaluation of anterior segment parameters between pregnancy trimesters and postpartum with pentacam scheimflug imaging: a prospective study.

PURPOSE: To evaluate the effect of pregnancy on the anterior chamber, corneal parameter, and intraocular pressure measurements; and compare the results between trimesters, postpartum and non-pregnant healthy age-matched women. METHODS: This prospective study included 41 pregnant women and 53 non-pregnant women. Four measurements were taken from the pregnant women, in each trimester and postpartum third month, and once from the control group. Of the individuals included in the study, anterior chamber depth (ACD), anterior chamber volume (ACV), K1 (flat keratometry), K2 (steep keratometry), Kmean (mean value of K1 and K2), anterior chamber angle (ACA), central corneal thickness (CCT), thinnest corneal thickness (TCT), astigmatism value (AST), corneal volume (CV), biometry, axial length (AL), spherical equivalent (SFEQ), intraocular lens power (ILP), VA (visual acuity) datas were recorded. RESULTS: We observed a statistically significant decrease in K2, CCT, ACD, AL and CV in the postpartum period (p = 0.025, p < 0.001, p = 0.029, p = 0.005, p = 0.004 respectively) and a statistically significant increase in ACV, CCT, and TCT as the gestational week progressed in the pregnant group (p = 0.007, p < 0.001, p = 0.025, respectively). A statistically significant decrease in IOP towards to the third trimester, and an increase in the postpartum period was observed (p < 0.001). We did not observe statistically significant changes in K1, Kmean, AST, ACA, VA, ILP, and SFEQ values. CONCLUSION: It is important to investigate the physiological changes that may occur during pregnancy, distinguish them from pathological changes, and avoid unnecessary treatment. We consider that it's also important to guide the timing of anterior segment surgeries such as cataract and refractive surgery and to prescribe glasses/contact lenses.

Repeatability assessment of anterior segment measurements in myopic patients using an anterior segment OCT with placido corneal topography and agreement with a swept-source OCT.

BACKGROUND: The precision of anterior segment biometric measurements in eyes has become increasingly important in refractive surgery. The purpose of this study is to assess the repeatability of the automatic measurements provided by a new spectral-domain optical coherence tomograph (SD-OCT)/Placido topographer (MS-39, CSO) and its agreement with a swept-source OCT (SS-OCT) biometer (CASIA SS-1000, Tomey) in patients with myopia. METHODS: The right eye of 235 subjects was scanned 3 times with both devices. The evaluated parameters included central corneal radius of the steep meridian, central corneal radius of the flat meridian, mean central corneal radius, thinnest corneal thickness, central corneal thickness, anterior chamber depth, corneal volume and diameter. The intraobserver repeatability of the MS-39 measurements was calculated using intraclass correlation coefficient (ICC), within subject standard deviation, coefficient of repeatability, coefficient of variation and repeated-measures analysis of variance of the 3 repeated measurements. The agreement between the two devices was evaluated by 95% limits of agreement (LoA). RESULTS: The majority of the parameters acquired from MS-39 showed high repeatability. The repeatability of corneal diameter was slightly lower than the other measurements, although the ICC remained high. Agreement with the CASIA SS-1000 was good, indicated by the Bland-Altman plots with narrow 95% LoA values for all parameters assessed. CONCLUSIONS: The high repeatability of automatic measurements by the new device supports its clinical application in eyes with myopia, and the good agreement between the two devices indicates they could be used interchangeably for the parameters evaluated.

Longitudinal Changes of Cornea Volume Measured by Means of Anterior Segment-Optical Coherence Tomography in Patients with Stable and Progressive Keratoconus.

Keratoconus is a corneal disease which results in progressive thinning and protrusion of the cornea leading to irregular astigmatism. The purpose of this study was to evaluate longitudinal changes in corneal volume (CV) occurring over time in keratoconus eyes. Consecutive patients affected by keratoconus were evaluated by means of anterior segment-optical coherence tomography (AS-OCT) at two different time points: baseline (T0) and after 1 year (T1). Anterior and posterior refractive value; corneal thickness at the thinnest point (TP) and corneal volume (CV) calculated within discs of 3, 5 and 8 mm of diameter; anterior chamber depth (ACD); and anterior chamber volume (ACV) were obtained. Enrolled patients were divided into 3 groups (groups 1, 2, 3) according to the increasing disease severity and into 2 groups (groups A, B) according to the progression or stability of the disease. Overall, 116 eyes of 116 patients (76 males and 40 females, mean age 34.76 ± 13.99 years) were included. For the entire group of keratoconus patients, in comparison with T0, mean TP decreased at T1 from 458.7 ± 52.2 µm to 454.6 ± 51.6 µm (p = 0.0004); in parallel, mean value of CV calculated at 5 mm and 8 mm decreased significantly (from 10.78 ± 0.8 at T0 to 10.75 ± 0.79 at T1 (p = 0.02), and from 32.03 ± 2.01 mm3 at T0 to 31.95 ± 1.98 at T1 (p = 0.02), respectively). Conversely, there were no statistically significant differences in CV at 3 mm from T0 to T1 (p = 0.08), as well as for ACD and ACV. Regarding the course of the disease, patients belonging to group A showed statistically significant differences from T0 to T1 for TP, and for CV at 3 mm, 5 mm and 8 mm (p < 0.0001, p < 0.0001, p < 0.001 and p = 0.0058 respectively). There were no statistically significant differences for ACD (p = 0.6916) and ACV calculated at 3, 5 and 8 mm (p = 0.7709, p = 0.3765, p = 0.2475, respectively) in group A. At the same time, no statistically significant differences for ACD (p = 0.2897) and ACV calculated at 3, 5 and 8 mm (p = 0.9849, p = 0.6420, p = 0.8338, respectively) were found in group B. There were statistically significant positive correlations between changes of TP and CV at 3 mm (r = 0.6324, p < 0.0001), 5 mm (r = 0.7622, p < 0.0001) and 8 mm (r = 0.5987 p < 0.0001). In conclusion, given the strong correlation with TP, CV might be considered an additional AS-OCT parameter to be used in association with conventional parameters when detecting longitudinal changes in keratoconic eyes.

Distribution and determinants of corneal volume among healthy young Chinese adults: a cross-sectional study.

BACKGROUND: Several studies have previously reported the normal values of corneal volume (CV) in various populations, whereas little is known about the CV distribution in healthy young Chinese adults. Our study aimed to investigate the distribution of CV and its relationships with other ocular biometric parameters among healthy young Chinese adults. METHODS: A total of 1645 eyes from 1645 students at Dali University in Yunnan Province, China, were analyzed. Pentacam was used to measure CV. Central corneal thickness (CCT) and biomechanically corrected intraocular pressure (bIOP) were evaluated by Corvis-ST. Other biometrical parameters, including axial length (AL), keratometry, and white-to-white (WTW) distance, were measured using IOL Master. RESULTS: The mean age of the study population was 19.01 ± 0.92 years, and 68.81% of them were women. The CV was normally distributed in the whole sample, with a mean value of 61.23 ± 3.22 mm3. CV and CCT were significantly smaller in the Yi ethnic group than in the Han ethnic group (p < 0.01). CCT (coefficient: 0.085; p < 0.001) and keratometry (coefficient: 0.422; p < 0.001) were positively correlated with CV, while AL (coefficient: -0.204; p < 0.001), WTW distance (coefficient: -0.236; p < 0.001) and bIOP (coefficient: -0.06; p < 0.001) were inversely associated with CV. CONCLUSIONS: Our study provides an age-specific distribution of CV among healthy young Chinese adults. CCT, keratometry, AL, WTW distance and bIOP were important factors associated with CV.

Correlation of corneal biomechanical changes with corneal volume changes and high-order aberration changes in the early stage after small incision lent-icule extraction / 眼科新进展

Objective To observe the corneal biomechanical changes of patients in the early stage after small inci-sion lenticule extraction(SMILE),and to analyze the correlation between the corneal biomechanical changes and changes in corneal volumes and higher-order aberrations.Methods A total of 72 patients(72 eyes)with myopia or myopic astig-matism who were scheduled for SMILE in the Optometric Center of Second People's Hospital of Foshan from January to August 2021 were included.The right eye was selected for observation.Before and 3 months after the SMILE,novel corne-al biomechanical parameters,such as biomechanical intraocular pressure(bIOP),DA ratiomax(2 mm)(DA2 ratio),inte-grated radius(IR),Ambrósio's relational thickness(for evaluation of the morphology and quality of the cornea,ARTh),stiffness parameter applanation 1(SP-A1),Corvis biomechanical index(CBI)and stress-strain index(SSI),were meas-ured by the new generation of Corvis? ST.The Pentacam anterior segment analysis system was used to measure corneal bi-omechanical parameters,including corneal volume(CV3 mm,CV5 mm,CV7 mm and CV10 mm);total root mean square of whole cornea,anterior and posterior corneal surface[RMS(Cornea,CF,CB)];root mean square of high-order aberrations of total cornea,anterior and posterior corneal surface[RMS HOA(Cornea,CF,CB)].Paired t-test or Wilcoxon singed-rank test was used to compare the changes in parameters before and after SMILE.Spearman correlation analysis and partial least squares regression were used to study the correlation between changes in novel corneal biomechanical parameters with cor-neal volume changes and high-order corneal aberration changes after the SMILE.Results Three months after SMILE,the bIOP,ARTh,SP-A1 and SSI decreased significantly,while the DA2 ratio,IR and CBI increased significantly(all P＜0.05).Three months after SMILE,CV3 mm,CV5 mm,CV7 mm and CV10 mm decreased significantly(all P＜0.05).The corneal volume changes from small to large were CV3 mm,CV5 mm,CV7 mm and CV10 mm,with a maximum decrease in the outmost periphery.The RMS(Cornea,CF,CB)and RMS HOA(Cornea,CF,CB)increased significantly(all P＜0.05);compared with the changes in high-order aberration on the anterior corneal surface,the changes in higher-order aberration on the posterior corneal surface were relatively stable.Correlation analysis shows that △ARTh was positively correlated with △CV3mm and△CV5mm,and negatively correlated with △CV10mm(all P＜0.05);△bIOP was negatively correlated with △CV3mm,△CV5mm,△RMS HOA(CF)and △RMS HOA(Cornea)and positively correlated with △CV10mm(all P＜0.05);△IR was negatively correlated with △CV10 mm(P＜0.05);△SP-A1 was positively correlated with △CV10 mm(P＜0.05);△ CBI was negatively correlated with △CV3 mm and △CV5 mm,and positively correlated with △CV10mmand △RMS(CF)(all P＜0.05).Conclusion The changes in corneal biomechanical parameters occur in the early stage after SMILE,with a certain corre-lation with the corneal volume changes in different regions and high-order corneal aberration changes.

Changes in corneal thickness, corneal volume, and densitometry after long-term orthokeratology wear.

PURPOSE: To investigate changes in the corneal volume, corneal densitometry and pachymetry of young myopes wearing over-night orthokeratology (OK) contact lenses. METHODS: The medical records of 28 right eyes of young myopes wearing OK between 2013 and 2018 were reviewed retrospectively. The baseline refractive error, best corrected visual acuities at baseline and uncorrected visual acuity at the most recent visit were recorded. Corneal volume of the central 10 mm cornea; densitometry at central, nasal and temporal cornea; and pachymetry along the horizontal and vertical meridians were collected from the Pentacam® HR at baseline, after one night of lens wear, and at the latest visit. RESULTS: The mean age of subjects was 12.03 ± 3.80 years at the time of OK lens fitting and wore OK overnight for a mean duration of 666 days (range 206-1736 days). The baseline spherical equivalent refractive error was -3.03 ± 1.56 D (range -1.00 to -6.00 D). The corneal volume increased significantly after OK wear (p = 0.001). Corneal densitometry increased after OK wear, but the change did not reach statistical significance (p = 0.113). Pachymetry in the central cornea did not change significantly across all visits (p > 0.05) but increased significantly in the mid-peripheral regions of the cornea. Baseline refractive error was not found to be correlated with the changes in corneal volume, corneal densitometry, or pachymetry. CONCLUSION: The increase in corneal volume and densitometry and no significant change in the central corneal thickness may indicate the presence of corneal oedema from long-term OK wear. The baseline refraction was not correlated with the changes in corneal volume, densitometry or pachymetry.

The short-term effects of intravitreal bevacizumab injection on intraocular pressure, cornea, iridocorneal angle, and anterior chamber.

Background: Transient increase in intraocular pressure (IOP), changes in anterior chamber parameters, and changes in aqueous humor dynamics may occur after intravitreal injections because of intravitreal volume changes. Objective: In this observational study, we investigated the early effects of intravitreal bevacizumab (IVB) injection on IOP, central corneal thickness (CCT), corneal volume (CV), anterior chamber depth (ACD), and iridocorneal angle (ICA). Method: The patients who had one single-dose IVB (2.5 mg/0.1 mL) injection were included in the study. The patients underwent IOP, CCT, CV, ACD, and ICA measurements before and 1 h and 1 day after the injection. Pre-injection and post-injection values were compared. Results: Forty-two eyes of 42 patients were included in the study, and the mean age of patients was 60.1 ± 7.4 years. The mean IOP measurements before and after injection at 1 h and day 1 were 15 ± 2.4, 17.4 ± 2.4, and 14.7 ± 2.3, respectively. The mean IOP, CCT, and CV values 1 h after injection were significantly higher than pre-injection values (p < 0.05, p < 0.05, and p = 0.02, respectively). Conversely, mean ACD and ICA values 1 h after injection were significantly lower than pre-injection values (p = 0.01 for both). There were no statistically significant differences on the first day after injection for all parameters. Conclusion: IVB (2.5 mg/0.1 mL) injection causes transient increases in IOP and transient decreases in ACD and ICA at the first hour after injection. Related to elevation in IOP, CCT and CV may increase transiently. These changes return to baseline values on the first day after injection.

Correlations of Immediate Corneal Tomography Changes with Preoperative and the Elapsed Phaco Parameters.

Purpose: The ability to predict corneal edema and understand its relationship with imaging parameters enables optimization of decision-making in terms of cataract surgery. Therefore, we aimed to elucidate the immediate tomographic alterations after phacoemulsification. Patients and Methods: In this prospective study, we evaluated clinical and corneal tomographic data of 30 patients with cataracts, obtained using a rotating Scheimpflug tomographic system before and after cataract surgery with a phacoemulsification system. Corneal thickness and volume were measured, and Pentacam Nucleus Staging, keratometry, and specular microscopy were performed preoperatively and immediately postoperatively. The Wilcoxon signed-rank test was used to compare pre-and postoperative values. We calculated the correlations between the changes in these values and multiple parameters related to phacodynamics, including "ultrasound (US) elapsed" (phaco time), "US average" (average power used), and "US absolute" (energy effectively dissipated, a product of the other two parameters). Results: There were increases in corneal volume (p<0.0001) and pachymetry (p<0.0001), and a decrease in endothelial cell count (p<0.0001) after surgery. The mean differences in pre- and postoperative specular microscopy, corneal volume, and pachymetry were -335.13±236.21 cells/mm3, 1.33±0.56 mm3, and 61.33±23.73 microns, respectively. The difference in pre-and postoperative corneal volume in patients with US elapsed ≥40 s was 0.75 mm3 greater than that in patients with US elapsed <40 s (95% confidence interval [CI]: 0.24-1.25; p=0.005); that of pachymetry in patients with US elapsed ≥40 s was 31.76 microns greater than that in patients with US elapsed <40 s (95% CI: 9.55-53.97; p=0.007). Spearman correlation revealed that, for every 1% increase in cataract density, the US average value increased by 0.31% (coef.: 0.3110; 95% CI: 0.0741-0.5490; p=0.012). Conclusion: Knowledge of Pentacam Nucleus Staging and the effect of US elapsed on differences in corneal volume and pachymetry before and after cataract surgery should be of particular value for surgeons who routinely encounter patients with hard cataracts.

Corneal and lens densitometry in patients with vernal keratoconjunctivitis.

AIM: To evaluate corneal and crystalline lens densitometry in patients with vernal keratoconjunctivitis (VKC). METHODS: This is a case-control study. Patients with VKC and age-gender-matched healthy controls underwent a complete ophthalmologic examination with corneal and crystalline lens densitometry measurements. Additionally, the anterior chamber parameters comprise anterior and posterior Kmean and astigmatism, anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), pachymeter, and corneal volume (CV). Patients who had clinically grade 0 or grade 1 VKC and with only tarsal conjunctiva involvement during the conductance of the study were included. The variables were compared statistically. RESULTS: One hundred and nine eyes were included in the study, in which fifty-one were in the VKC group. There were 25 males in the VKC group (26 female) and 22 males in the control group (36 female). A statistically significant difference was found between the groups in terms of posterior corneal astigmatism (p = 0.02). The mean corneal pachymeter, CV, ACD, ACA, and ACV were similar in both groups (p = 0.63, p = 0.26, p = 0.60, p = 0.41, and p = 0.32, respectively). The total mean corneal densitometry in the zones extending from 6 to 10 mm and 10 to 12 mm was increased in the VKC group compared to the control group (p = 0.04 and p = 0.012, respectively). The mean crystalline lens was found to be denser in the VKC group compared to the control group (8.96 ± 1.6 vs. 8.5 ± 0.57, respectively, p = 0.04). CONCLUSION: Posterior corneal astigmatism is increased in VKC cases in comparison with age- and gender-matched controls. The peripheral anterior 6-12 mm annular corneal zone showed increased corneal densitometry in VKC cases compared to the healthy subjects. Additionally, the lens clarity is found to be decreased subclinically in VKC cases compared to control cases.

Evidence of a Down Syndrome Keratopathy: A Three-Dimensional (3-D) Morphogeometric and Volumetric Analysis.

The aim of this study was to investigate whether a different and abnormal corneal profile is present in Down syndrome (DS) by personalized three-dimensional (3D) modelling. This single-centre cross-sectional study included 43 patients with DS (43 eyes) and 58 age-sex-matched control subjects (58 eyes) with normal karyotype and topography. Refraction, central corneal thickness (CCT), aberrations (high-order, coma and spherical), asphericity and morphogeometric/volumetric parameters based on a 3D corneal model that was generated from raw topographical data were evaluated. Deviation of anterior/posterior apex (Dapexant/Dapexpost) and thinnest point (Dmctant/Dmctpost) from corneal vertex, anterior/posterior surface area (Aant/Apost), sagittal area passing through the anterior/posterior apex (Aapexant/Aapexpost) and thinnest point (Amctpost), total corneal volume (Vtotal) and volumetric progression for each 0.05 mm step of the radius value centred to the thinnest point (VOLMCT) and anterior/posterior apex (VOLAAP/VOLPAP) comprised the morphogeometric/volumetric parameters. In the DS group, 58.1% of the eyes presented abnormal topography. High-order and coma aberrations, asphericity, Dapexant, Aant, Apost and Aapexant were significantly higher, whereas CCT, Aapexpost, Amctpost, Vtotal, VOLAAP, VOLPAP and VOLMCT were lower in the DS group than in the control group (p < 0.05). Dapexpost did not differ between the groups (p > 0.05). This study demonstrates that corneas of the subjects with DS are different and more aberrated than those of normal age- and sex-matched non-DS controls. Anterior corneal apex appears to be displaced in DS even with normal topography, while posterior apex seems stable although topography is abnormal. These findings may help to modify our approach in the diagnosis of keratopathy in subjects with DS.

Relationship between Corneal Morphogeometrical Properties and Biomechanical Parameters Derived from Dynamic Bidirectional Air Applanation Measurement Procedure in Keratoconus.

The morphogeometric analysis of the corneal structure has become a clinically relevant diagnostic procedure in keratoconus (KC) as well as the in vivo evaluation of the corneal biomechanical properties. However, the relationship between these two types of metrics is still not well understood. The current study investigated the relationship of corneal morphogeometry and volume with two biomechanical parameters: corneal hysteresis (CH) and corneal resistance factor (CRF), both provided by an Ocular Response Analyzer (Reichert). It included 109 eyes from 109 patients (aged between 18 and 69 years) with a diagnosis of keratoconus (KC) who underwent a complete eye examination including a comprehensive corneal topographic analysis with the Sirius system (CSO). With the topographic information obtained, a morphogeometric and volumetric analysis was performed, defining different variables of clinical use. CH and CRF were found to be correlated with these variables, but this correlation was highly influenced by corneal thickness. This suggests that the mechanical properties of KC cornea contribute only in a partial and limited manner to these biomechanical parameters, being mostly influenced by morphogeometry under normal intraocular pressure levels. This would explain the limitation of CH and CRF as diagnostic tools for the detection of incipient cases of KC.

Subclinical keratoconus detection with three-dimensional (3-D) morphogeometric and volumetric analysis.

PURPOSE: To assess the efficacy of morphogeometric and volumetric characterization of the cornea based on three-dimensional (3-D) modelling in diagnosis of subclinical keratoconus (KC). METHODS: Cross-sectional study. Ninety-three eyes with subclinical KC with a best spectacle-corrected distance visual acuity ≥20/20 (grade zero KC according to the RETICS classification) and 109 control eyes were included. Computer-based 3-D corneal morphogeometric model was generated using raw topographic data. Distance-, area- and volume-based parameters were used for statistical analysis. Distance parameters included deviation of anterior (Dapexant )/posterior (Dapexpost ) apices and minimum thickness points (Dmctant , Dmctpost ) from corneal vertex, and Dapexant -Dapexpost difference. Areal variables were derived from anterior (Aant ) and posterior (Apost ) corneal surfaces, sagittal plane passing through corneal apices (Aapexant , Aapexpost ) and thinnest point (Amctant , Amctpost ). Total corneal volume (Vtotal ) and volumetric distribution (with 0.1mm steps) centred to thinnest corneal point (VOLmct ) and anterior (VOLaap )/posterior (VOLpap ) apices comprised the volume-based parameters. RESULTS: In the subclinical KC group, all D values, Dapexant -Dapexpost difference, Aant , Apost and Aapexant values were higher (p < 0.001), while Aapexpost , Amctpost , Vtotal , VOLmct , VOLaap and VOLpap values were lower when compared to the control group (p < 0.001). Regression analysis-based formula correctly classified 96.8% of the eyes with subclinical KC and 94.5% of the normal ones (p < 0.0001). CONCLUSIONS: Eyes with subclinical KC seem to represent asymmetrically displaced anterior and posterior corneal apex, corneal thinning and volume loss. 3-D morphogeometric and volumetric parameters and differentiation formula can be incorporated into topography software to detect subclinical KC with high sensitivity and specificity in clinical practice.

Corneal Involvement of Patients with Polymyositis and Dermatomyositis.

Purpose: To evaluate corneal parameters in patients with polymyositis (PM) and dermatomyositis (DM) and compare them with those of healthy controls.Methods: A total of 43 PM and 32 DM patients and 93 controls were enrolled in this cross-sectional, observational, case-control study. Corneal parameters were evaluated by Pentacam. Objective clinical tests of dry eye disease (DED) were also performed.Results: All pachymetric measurements and corneal volumes (CVs) proved to be significantly lower both in PM and DM patients. The values of DM patients were closer to control values than those of the PM patients. For tear break-up time and Schirmer-I test values significant differences were observed between patients and controls, with values decreased both in PM and DM patients.Conclusions: PM patients rather than DM patients tend to develop thinner and low-volume corneas as compared to controls. Additionally, a high prevalence of DED among both PM and DM patients was also detected.

Comparison of the corneal volume and the anterior chamber volume using Pentacam in individuals with healthy, subclinical and early keratoconus eyes / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To compare the anterior chamber volume and corneal volume using Pentacam in people with early keratoconus, subclinical keratoconus, and healthy subjects.<p>METHODS: This epidemiologic study was performed on 63 patients who were candidates for refractive surgery. We classified our patients into three groups as normal, subclinical keratoconus, and early keratoconus according to the Amsler-Krumeich criteria. We collected demographic information, including age and sex, and obtained a full medical history of the patients. Complete visual examination was performed for all patients. Then, using Pentacam, corneal volume and anterior chamber volume were measured among three groups. <p>RESULTS: Corneal volume in the control group was significantly higher than the subclinical keratoconus and early keratoconus groups(<i>P</i><0.05), but the anterior chamber volume was not significantly different between the groups(<i>P</i>>0.05).<p>CONCLUSION: Measuring the corneal volume can help to distinguish the eyes with subclinical keratoconus and early keratoconus from normal eyes. The chamber volume might not differ remarkably among people with subclinical keratoconus, early keratoconus, and those with normal eyes.

Corneal Manifestations of Inflammatory Bowel Disease.

Purpose: To evaluate detailed corneal parameters of inflammatory bowel disease (IBD) patients, including Crohn's disease (CD) and ulcerative colitis (UC) patients, and to assess associations between anterior segment values and other clinical variables.Methods: This prospective cross-sectional case-control study at a tertiary referral center included 30 CD patients, 36 UC patients and 80 age- and gender-matched controls with no ocular symptoms or ocular surface disorders. All study participants underwent a comprehensive ophthalmological evaluation with special interest in dry eye disease (DED). Corneal parameters were evaluated by Pentacam.Results: The mean age of CD patients, UC patients, and controls was 45.80 ± 11.55 years, 52.00 ± 16.05, and 50.68 ± 14.62, respectively. The average disease duration was 12.72 ± 5.83 years for CD patients and 15.94 ± 10.09 years for UC patients. All pachymetric (center, apex and thinnest) and corneal volume (CV) measurements were significantly decreased, while anterior chamber angle width (ACA) values were significantly increased on both sides in all IBD patients compared to those in controls (p < .05). In addition, several anterior segment parameters were altered unilaterally in CD or UC patients. Negative correlations were found between corneal parameters and Schirmer I test values.Conclusions: Our investigations suggest that IBD patients have thinner corneas compared to that of controls. The coexistence of reduced tear quantity seems to have an additional impact on the thinning of the cornea in IBD patients. Early recognition of corneal impairments, a possible extraintestinal manifestation of IBD, should be included in the disease checkup to reduce vision-threatening developments.

Central corneal thickness and corneal volume changes in eyes with and without pseudoexfoliation after uneventful phacoemulsification.

AIM: To investigate the effects of uneventful phacoemulsification on central corneal thickness (CCT) and corneal volume (CV) in pseudoexfoliative eyes during a 3 months postoperative period and compare these changes to eyes without pseudoexfoliation (PEX) syndrome. Another purpose of this study was to compare the CCT measurements done by ultrasound pachymetry (UP) with those done by the Oculus Pentacam. MATERIAL AND METHOD: A total of 42 eyes of 42 consecutive patients with cataracts and PEX syndrome that underwent uneventful phacoemulsification were enrolled in this prospective study. A control group of 42 eyes of 42 patients with cataracts/without PEX was employed for comparison. CV and CCT measurements were obtained preoperatively and at 1 and 3 months postoperatively with the Pentacam. CCT values were also measured with UP. T test and Wilcoxon sign test were used to compare the variables. RESULTS: The mean age of the patients was 72.1 ± 8.3 and 66.6 ± 9.6 years in PEX and non-PEX group, respectively. In both groups, there were no significant differences between preoperative and postoperative CV (Fig. 1), CCT by the Pentacam (Fig. 2) and CCT by UP (Fig. 3) values (p > 0.05). CCT measurements obtained by two devices were also similar, and there were no statistically significant differences (p > 0.05). Changes in CV and CCT remained stabile at 3 months postoperatively. CONCLUSION: Eyes with and without PEX syndrome exhibit similar corneal features before and after phacoemulsification. A surgery in early stages of cataracts in PEX syndrome, not only provides a non-complicated surgery, but also leads to a less damaged cornea similar to eyes without PEX.

Corneal Manifestations of Systemic Sclerosis.

Purpose: Corneal involvement in systemic sclerosis (SSc) is rare, but due to rich collagen composition cornea is especially vulnerable to connective tissue diseases. Therefore, our aim was to evaluate corneal parameters of SSc patients. Methods: The study included 32 SSc patients and 39 control subjects with no ocular symptoms or ocular surface disorders. All study participants underwent Pentacam evaluation and objective signs of dry eye disease (DED), and clinical parameters were evaluated. Results: All pachymetric values, most of the corneal front surface, corneal volume, as well as anterior chamber depth measurements were significantly lower in the SSc group than in the control group (p < 0.05). Significant negative correlation was found between corneal parameters and age on the one hand, and disease duration on the other. Conclusions: Early recognition of corneal impairment, a possible extraintestinal manifestation of SSc, should be included in the check-up of the disease in order to reduce sight-threatening complications.

Five-Year Changes of Anterior Corneal Indices in Diabetics versus Non-Diabetics: The Shahroud Eye Cohort Study.

PURPOSE: To compare 5-year changes of central and peripheral corneal thickness, corneal volume, and keratometry between diabetic and non-diabetic individuals (>40 years) in a population-based study. MATERIALS AND METHODS: Right eye corneal indices of the 333 diabetic persons were compared with 2865 non-diabetics. Studied indices included the apical corneal thickness (ACT), minimal corneal thickness (MCT), thickness values on corneal rings of 4 mm, 6 mm, and 8 mm in diameter, the volume of the 10 mm of the corneal diameter, and the central 3 mm keratometry in two steep (Kmax) and flat (Kmin) axes as measured with Pentacam (Oculus, Inc, Lynnwood, WA). RESULTS: In the diabetic and non-diabetic groups, respectively, the 5-year change was +0.1 ± 11.9 and -1.2 ± 11.9 µm (p = 0.035) for ACT, -1.1 ± 12.1 and -2.4 ± 11.9 µm (p = 0.056) for MCT, -3.9 ± 12.6 and -5.1 ± 12.3 µm (p = 0.007) for the 4 mm ring, -5.0 ± 15.3 and -7.5 ± 14.5 µm (p = 0.006) for the 6 mm ring, and -7.0 ± 20.1 and -10.8 ± 19.2 µm (p = 0.011) for the 8 mm ring. The diabetic group showed less reduction in corneal volume (-0.5 ± 1.8 mm3) compared to non-diabetics (-0.8 ± 1.6 mm3) (p = 0.030). Kmax (+0.3 ± 0.5D vs. +0.4 ± 0.5, p = 0.028) and Kmin (+0.4 ± 0.5D vs. +0.5 ± 0.5, p = 0.005) showed less change in diabetics compared to non-diabetics. CONCLUSIONS: The overall patterns of change in corneal thickness and shape in over 40-year old diabetics are similar to non-diabetics, such that with aging, reduced thickness and increased keratometry take the cornea towards a prolate shape. However, the age-related changes in central and peripheral corneal thickness, volume and corneal shape are less pronounced in diabetic subjects.

Comparative Analysis of One-Handed and Two-Handed Coaxial Phacoemulsification with 2.4-mm Clear Corneal Incision.

PURPOSE: To compare the efficiency and safety of one-handed and two-handed coaxial phacoemulsification Material and Methods: Patients with cataracts underwent one-handed (one-handed group) or two-handed coaxial phacoemulsification (two-handed group) with a 2.4-mm clear corneal incision. Intraoperative phaco parameters, total surgical time, postoperative visual acuity, surgically induced astigmatism (SIA), corneal volume (CV), central corneal thickness (CCT) and corneal endothelial cell counts/size were compared between the two groups. RESULTS: Each group comprised 105 eyes. There were no significant differences in the intraoperative phaco parameters and total surgical time between the two groups (all p > 0.05). Visual outcomes were significantly better in the one-handed group than in the two-handed group 1 week postoperatively (all p< 0.05) but not 1 month postoperatively. There was no significant difference in SIA between the two groups 1 week (p = 0.695) or 1 month postoperatively (p = 0.772). CV, CCT and endothelial cell loss were significantly lower in the one-handed group than in the two-handed group 1 week postoperatively (CV: p = 0.004; CCT: p = 0.046; endothelial cell loss: p = 0.021), but the above differences were absent 1 month postoperatively except for endothelial cell loss (endothelial cell loss: p = 0.038). CONCLUSIONS: Both one-handed and two-handed coaxial phacoemulsification were effective and safe surgical techniques. However, the one-handed technique had the advantages of less trauma to the cornea and better early clinical outcomes than the two-handed technique for cataract patients within nuclear opalescence (NO) 3 grade ≤ 3.

Comparison of variations in cornea after one-handed and two-handed coaxial phacoemulsification.

PURPOSE: To compare corneal variations in patients undergoing one-handed and two-handed coaxial phacoemulsification. SETTING: Eye Institute, Affiliated Hospital of Nantong University, Nantong, China. DESIGN: Prospective consecutive nonrandomized comparative cohort study. METHODS: Patients with cataracts were subject to one-handed (one-handed group) or two-handed coaxial phacoemulsification (two-handed group). Intraoperative phaco parameters and postoperative outcomes, such as visual acuity, surgically induced astigmatism (SIA), corneal volume, central corneal thickness, and corneal endothelial cell counts/size were compared. RESULTS: No significant differences in the intraoperative phaco parameters were noted between the 2 groups. At postoperative week 1, visual outcomes were significantly improved in the one-handed compared with the two-handed group (all P<0.05). Corneal volume, central corneal thickness, and average cell size were significantly decreased in the one-handed group compared with two-handed group (all P<0.05), but the aforementioned differences were ameliorated at 1 month and 3 months postoperatively. Endothelial cell loss was significantly decreased in the one-handed group compared with the two-handed group at any follow-up point (all P<0.05). No significant differences in SIA on the anterior surface were noted between the 2 groups. SIA on the posterior surface was significantly decreased in the one-handed group compared with the two-handed group at 1 week postoperatively (P=0.043) but not at 1 month and 3 months postoperatively. CONCLUSION: One-handed phacoemulsification has the advantages of less trauma to the cornea and better early visual outcomes compared with the two-handed technique.