Corneal Densitometry Values Research Articles

Scheimpflug Corneal Densitometry Values and Severity of Guttae in Relation to Visual Acuity in Fuchs Endothelial Corneal Dystrophy.

The purpose of this study was to investigate the association between corneal densitometry (CD) values from Scheimpflug tomography imaging, severity of guttae, and visual acuity in eyes with Fuchs endothelial corneal dystrophy (FECD). This was a retrospective, cross-sectional study. Patients with FECD were examined at the Bascom Palmer Eye Institute from January 2015 to September 2019. We extracted CD values at central annuli of 0-2, 2-6, 6-10 and 10-12 mm from Scheimpflug tomography images. We investigated the association of corrected distance visual acuity (CDVA) with CD values, severity of guttae, central corneal thickness (CCT), cataract grade, refractive error, corneal edema grade, age, and gender using multivariate generalized estimating equation regression models. One hundred ninety-two eyes from 110 patients were included in this study. Increase in central CD values at the 0 to 2 mm zone (P < 0.001), severity of guttae (P = 0.046), age (P < 0.001), cataract grade (P < 0.001), corneal edema grade (P < 0.001), and type of refractive error (P = 0.008) were significantly associated with decreased CDVA. Central corneal thickness, sex, and the peripheral CD values (2-6, 6-10, and 10-12 mm) were not significantly associated with CDVA (P > 0.05) in the final multivariate regression model. Our study demonstrates that central CD values at 0 to 2 mm and severity of guttae are each associated with decreased CDVA in FECD. These findings carry implications for patients with FECD considering surgical intervention for phacoemulsification alone, Descemet stripping only, or endothelial cell transplantation and provide a multifactorial perspective on vision loss in FECD.

Evaluation of Corneal Densitometry and Endothelial Layer in Soft Contact Lens Users.

Soft contact lens wear may lead to physiological changes in the cornea. Corneal densitometry is a new software tool that may detect these physiological changes by monitoring their effects on corneal transparency. This study aimed to assess corneal densitometry values and corneal endothelium in patients using soft contact lenses. The study included 36 eyes of 36 subjects with soft contact lens use (group 1) and 36 eyes of 36 healthy control subjects (group 2). Anterior segment parameters and corneal densitometry of all subjects were evaluated using Scheimpflug corneal topography (Pentacam; Oculus Inc., Wetzlar, Germany). A total corneal area of 12 mm was divided into four annular zones (0 to 2, 2 to 6, 6 to 10, and 10 to 12 mm) and into three regions as anterior, central, and posterior for densitometry examination. Cell density, cell distribution, and cell morphology (quadrangular, pentagonal, hexagonal, and other cell percentages) of the endothelial layer were examined in both groups using specular microscopy (Nidek CEM 530; Nidek Co., Gamagori, Aichi, Japan). In group 1, the mean duration of contact lens wear was 4.45 ± 2.15 years. The anterior segment parameters were not significantly different between the two groups (P > .05). The anterior 0- to 2- and 2- to 6-mm corneal densitometry values were significantly higher in group 1 compared with group 2 (23.2 ± 4.7 for group 1 and 17.3 ± 5.6 for group 2 [P = .03]; 22.4 ± 6.4 for group 1 and 17.8 ± 1.4 for group 2 [P = .03], respectively). There were no significant differences between the groups for corneal densitometry values between 6 and 12 mm, or for cell density, cell distribution, and cell morphology (P > .05). Although the cornea remains transparent in soft contact lens wearers, corneal densitometry may increase in the 0- to 6-mm annular zone of the anterior region.

Anterior Chamber Characteristics, Endothelial Parameters, and Corneal Densitometry After Descemet Stripping Automated Endothelial Keratoplasty in Patients With Fuchs Dystrophy.

PurposeTo compare anterior segment parameters in patients with Fuchs endothelial dystrophy (FED) who underwent Descemet stripping automated endothelial keratoplasty (DSAEK) in one eye and no corneal surgery in the fellow eye.MethodsThis prospective study was conducted on 28 eyes of 14 patients with FED who underwent DSAEK in one eye at least one year prior (DSAEK group) and no corneal surgery in the fellow eye (control group). Each eye was analyzed with the anterior segment optical coherence tomography, specular microscopy, and Scheimpflug imaging systems. Data were compared between the two groups.ResultsThe mean age of the patients was 76.9 7.0 years. There were no statistically significant differences in the mean central corneal thickness (CCT), central anterior chamber depth, anterior chamber angle parameters, cylinder and keratometry values between two groups (all P-values 0.05). The paracentral corneal thickness, corneal volume, endothelial cell density, and hexagonal cell ratio measurements were statistically significantly higher in the DSAEK group than the control (all P-values < 0.05), and anterior chamber volume in the DSAEK group was significantly less than the control (P = 0.046). While posterior and total corneal densitometry values in the DSAEK group were statistically significantly lower than the control (P < 0.001 and P = 0.011, respectively), there were no statistically significant differences in the anterior or middle corneal densities (P = 0.108 and P = 0.134, respectively).ConclusionWe found that total corneal densitometry value decreased in DSAEK group. Although DSAEK surgery did not affect the anterior chamber angle parameters, it reduced the anterior chamber volume and increased the corneal volume and paracentral corneal thickness due to the addition of the DSAEK graft.

Evaluation of corneal densitometry changes in patients with lichen planus.

To investigate the corneal topography and densitometry changes in patients with lichen planus (LP). Anterior segment parameters and corneal densitometry of patients with LP and age- and gender-matched individuals with healthy eyes were evaluated using Scheimpflug corneal topography. A 12mm corneal area was divided into 4 annular zones and 3 regions-in-depth anterior, central and posterior-for densitometry evaluation. The study included 45 patients with LP and 50 individuals with healthy eyes. The two groups were similar in age and gender, and they showed no significant differences in anterior segment corneal topography parameters. Schirmer's I test results were significantly lower in the patients with LP than in the control group (P˂.001). The total corneal densitometry was higher in patients with LP than in the control group (P=.030). The anterior, central and posterior corneal densitometry in the 0-2mm and 2-6mm annular zones was higher in the LP group than in the control group. Correlation analysis between disease duration and corneal densitometry values showed a strong positive correlation in the anterior segment and a moderate positive correlation in the central and posterior segments (r=0.632, P˂.001; r=0.572, P˂.001; and r=0.562, P˂.001, respectively). Corneal densitometry values were higher in patients with LP than in individuals with healthy eyes, even if the patients had a clinically transparent cornea. More studies are needed to evaluate the changes that may occur in corneal transparency in patients with LP and other autoimmune dermatologic diseases that may affect the eye.

A four-year observation of corneal densitometry after implantable collamer lens V4c implantation.

To observe the changes in corneal densitometry (CD) with a Pentacam after implantable collamer lens (ICL) V4c implantation in myopia patients, and to investigate potential influencing factors. We reviewed 65 eyes of 33 patients (mean age, 29.08±5.54 years) with myopia or myopic astigmatism who underwent ICL V4c implantation. Clinic parameters and Pentacam images of corneal topography and CD were obtained pre- and postoperatively. After an average of 52±2.2 months follow-up, the efficacy and safety indexes assessed at the last follow-up were 1.03±0.18 and 1.21±0.21, respectively. Except in the central annular zone of 0-2 mm, the CD values increased significantly at postoperative day 1 and decreased significantly until postoperative 1 year (P<0.05). The increase in CD values at different annular zones at postoperative day 1 was ranked as: 0-2 mm <2-6 mm < 6-10 mm. No significant difference was observed in corneal density at 1 week, 1 month, and 1-year follow-up when compared with the preoperative value (P>0.05). The CD value at 4 years follow-up increased significantly and correlated positively with age and preoperative uncorrected distance visual acuity, and negatively with preoperative spherical equivalent and intraocular pressure (IOP) (P<0.05). ICL V4c implantation demonstrated safety and efficacy for myopia correction. The CD value increased at 4 years postoperatively and correlated with age, preoperative spherical equivalent, uncorrected distance visual acuity, and IOP.

Corneal Densitometry Assessed With Scheimpflug Camera in Healthy Corneas and Correlation With Specular Microscopy Values and Age.

To investigate correlations between specular microscopy endothelial parameters and age with corneal densitometry values, as they are presented from a Scheimpflug device, in different levels of the cornea. Two hundred eighty-four eyes of 142 healthy subjects were included in this observational, prospective study. Corneal densitometry was evaluated with Scheimpflug imaging system in the central 0- to 2-mm annular zone of the cornea, whereas the endothelial cell properties were assessed with the use of a noncontact specular microscope. Corneal densitometry values of all corneal layers were statistically significant and positively correlated with age. In univariate linear regression analysis among corneal densitometry values and the endothelial parameters, only endothelial cell density (CD) was statistically significant and inversely correlated with densitometry values in all corneal layers. In stepwise multivariate linear regression analysis, after adjustment for age, hexagonality was statistically significant and inversely correlated with posterior densitometry values, whereas coefficient of variation was positively and significantly correlated with the anterior densitometry values. When repeating stepwise multivariate linear regression analysis without adjusting for age, CD was negatively and significantly correlated with corneal densitometry values of all layers, whereas coefficient of variation was positively and significantly correlated with anterior and total corneal densitometry values. Corneal densitometry increases with age. It is also inversely correlated with CD, and this might be used as an indirect way to assess the status of the corneal endothelium.

Evaluation of topographic, tomographic, topometric, densitometric, and aberrometric features of cornea with pentacam HR system in subclinical keratoconus.

To investigate topographic, tomographic, topometric, densitometric, and aberrometric parameters in subclinical keratoconus with the Pentacam HR imaging system. Data of 3128 patients were evaluated, finding in 108 patients clinical keratoconus in one eye and subclinical keratoconus in the other. Corneal topographic, tomographic, topometric, densitometric, and aberrometric values obtained using the Pentacam HR imaging system were compared between clinical keratoconus, subclinical keratoconus, and normal eyes. Comparing eyes with subclinical keratoconus and the control group, while flat K, horizontal coma, horizontal trefoil, and vertical trefoil values were similar (p > 0.05 for each), all other parameters were significantly different (p < 0.05 for each). Densitometry values of eyes with subclinical keratoconus were significantly higher in all layers of the 0-2mm annular area and in the anterior and central layers of the 2-6mm annular area compared to the control group (p < 0.05 for each). According to the receiver operating characteristic curve analysis, the densitometry region with the largest area under the curve was the anterior layer of the 0-2mm annular area. The sensitivity in this region was 79.4% and the specificity 73.2% in distinguishing eyes with subclinical keratoconus from normal eyes when 19.3 GSU was considered the threshold. Corneal densitometry values in the 0-2 and 2-6mm annular areas, especially in the anterior layers, are parameters that can be used to predict and distinguish subclinical keratoconus from normal eyes.

Corneal densitometry patterns in Descemet membrane endothelial keratoplasty and Descemet stripping automated keratoplasty.

To compare corneal densitometry in a consecutive series of 52 endothelial keratoplasties (DMEK/DSAEK) using a Scheimpflug-based device after six months of follow-up. Corneal densitometry (CD) values of 102 eyes were divided into three main groups: 33 DMEKs, 19 DSAEKs, and 50 healthy eyes without previous ocular surgery. The CD values were then analyzed and compared between the groups. We measured three main layers in depth and four different concentric zones at 1, 3, and 6months postoperatively. In the DMEK group, total CD significantly decreased from 38.02 ± 10.21 grayscale units (GSU) to 31.13 ± 9.25 GSU (P < 0.01) between the first and the sixth month postoperative. In the DSAEK group, we found significant changes only between the first and three months after surgery (from 42.62 ± 9.31 GSU to 38.71 ± 10.53 GSU (P < 0.01). Regarding the concentric zones, CD in the DMEK group significantly decreased in the central zone from 33.55 ± 12.07 GSU to 30.63 ± 10.15 GSU (P < 0.01) and significantly increased in the periphery from 30.63 ± 10.15 GSU to 36.72 ± 9.37 GSU, (P < 0.01). The DSAEK group showed no changes in the central zone (from 36.91 ± 13.80 GSU to 36.14 ± 11.47 GSU, P = 0.52) and CD significantly increased in the periphery (41.91 ± 9.28 GSU, P < 0.01). When comparing CD values in DMEK versus DSAEK, we found no differences by layers or at central-paracentral concentric zones, although CD differences in the peripheral zones were statistically significant. This finding may be attributed to the thicker graft at periphery with a delayed clearance and less anatomical interphase in DSAEK.

Investigation of corneal topographic and densitometric properties of Wilson's disease patients with or without a Kayser-Fleischer ring

BackgroundTo investigate the topographic measurements and densitometry of corneas in Wilson’s disease (WD) patients with or without a Kayser-Fleischer ring (KF-r) compared to healthy individuals.MethodsThis cross-sectional study included 20 WD patients without a KF-r (group I), 18 WD patients with a KF-r (group II), and 20 age-matched controls (group III). The Pentacam high resolution imaging system is used to determine corneal topographic measurements and densitometry.ResultsMean age for groups I, II and III was 25.40 ± 6.43 years (14–36 years), 25.38 ± 6.96 years (16–39 years), 23.60 ± 6.56 years (17–35 years), respectively (P = 0.623). There was no significant difference between the groups in terms of the anterior corneal densitometry values (P > 0.05), while the 6–10 mm and 10–12 mm mid stroma and the 2–6 mm, 6–10 mm, and 10–12 mm posterior corneal densitometry values in group II were significantly higher than those in groups I and III (for all values, P < 0.05). However, the 10–12 mm posterior corneal densitometry values in group I were also significantly higher than those in group III (P = 0.038). The central corneal thickness (CCT), thinnest corneal thickness (tCT), and corneal volume (CV) values in groups I and II were significantly lower than those in group III (for CCT values, P = 0.011 and P = 0.009; for tCT values, P = 0.010 and P = 0.005; for CV values, P = 0.043 and P = 0.029).ConclusionIn WD patients with a KF-r, corneal transparency decreased in the peripheral posterior and mid stromal corneal layers; for these patients, corneal transparency may be impaired not only in the peripheral cornea but also in the paracentral cornea.

Evaluation of Corneal Optic Quality in Amblyopia

Objective: To compare corneal aberrations and densitometry values in children with amblyopia due to anisometropic hyperopia with those of healthy children.&#x0D; Methods: This study included 173 children with amblyopia due to hyperopic anisometropia in one eye and 173 children with both healthy eyes. The amblyopic eye (Group 1) and the fellow normal eye (Group 2) of the amblyopic patients and the right eye of the healthy control group (Group 3) were evaluated. Of the corneal aberration and corneal densitometry (CD)measured using Scheimpflug corneal topography values were noted.&#x0D; Results: While there was a significant difference in total root mean square (RMS), higher-order aberration (HOA) RMS, coma horizontal, trefoil horizontal and spherical aberration values between the groups (p

Corneal and lens densitometry with Pentacam HR in children with vernal keratoconjunctivitis

ABSTRACT Clinical relevance Corneal and lens densitometry measurements provide clinically important information for the evaluation and monitoring of corneal and lens health in patients with vernal keratoconjunctivitis. Background To compare the corneal and lens densitometry values between paediatric patients with vernal keratoconjunctivitis (VKC) and healthy individuals. Methods This study included 72 eyes of 72 patients with VKC (25 with mild VKC [Group 1], 22 with moderate VKC [Group 2], and 25 with severe VKC [Group 3]), and 25 eyes of 25 healthy subjects (Group 4). Corneal and lens densitometry values were measured using Pentacam HR as follows: for corneal densitometry in two different corneal zones (0–2 and 2–6-mm) and four different corneal depths (at the total thickness, anterior, central, and posterior layers), and lens densitometry in three different lens zones (Zone 1: 2.0-mm, Zone 2: 4.0-mm, and Zone 3: 6.0-mm). Results In the 0–2-mm corneal zone for the total thickness and all three layers, corneal densitometry values in Group 3 were significantly higher than those in Groups 1, 2, and 4 (for all values p < 0.012). There was no significant difference in the mean corneal densitometry values between Groups 1 and 2 (for all values p > 0.05). In these groups, the mean corneal densitometry values were significantly higher than those in Group 4 for the anterior layer in the 0–2 and 2–6-mm corneal zones (for all values p < 0.012). The mean values for Zone 3 and average lens densitometry values in Groups 2 and 3 were significantly higher than those in Group 4 (p = 0.001 and p = 0.001, respectively). Conclusion The current study showed corneal clarity changes in patients with mild, moderate, and especially severe VKC. An increase in the lens densitometry values was also observed in patients with moderate and severe VKC than in healthy individuals.

Corneal and lens clarity in patients with chronic obstructive pulmonary disease

ABSTRACT Clinical relevance Understanding the reduction in clarity of the ocular media in patients with chronic obstructive pulmonary disease (COPD) will aid interpretation of ocular examinations and refractive assessments in patients with this condition. Background To investigate corneal and lens densitometry measurements of patients with COPD and to compare the results obtained with those in healthy adults. Methods This prospective cross‐sectional study included 25 newly diagnosed COPD patients (COPD group) and 35 healthy subjects (control group). The COPD patients were excluded if they ever had any recorded systemic or inhaler steroid therapy. After recording demographic and clinical characteristics, eligible study subjects underwent a through ophthalmic evaluation which included measurement of refractive errors using the same automatic refractor‐keratometer device, best‐corrected visual acuity determination using a Snellen chart, measurement of intraocular pressure using a pneumotonometer, slitlamp biomicroscopy and fundus examination. After general ophthalmic examination, the Pentacam HR imaging system was used to evaluate corneal and lens densitometry measurements of the groups. Results There were no statistically significant differences in the ages and genders of the participants between the two groups (p > 0.05). Additionally, the mean values of intraocular pressure, refractive error and body mass index as well as smoking status were similar between the groups (p > 0.05, for all). The mean corneal densitometry values were also similar in all the concentric zones and layers in the eyes of the patients with COPD and controls (p > 0.05, for all). However, the mean values of zones 1, 2 and 3, and average lens densitometry measurements of the COPD group, were statistically significantly higher compared to control subjects (p < 0.05, for all). Conclusion Lens clarity of patients with COPD was significantly decreased while corneal densitometry measurements were not significantly affected.

The Effect of Chalazion Excision on Corneal Aberrometric and Densitometric Values.

Objectives:The aim of this study was to investigate the effect of chalazion excision on corneal aberrations and corneal densitometry.Methods:Thirty-six patients with a chalazion in 1 eyelid and 40 healthy subjects were included in the study. Corneal aberration parameters of total root mean square (RMS), RMS high-order aberration (HOA), horizontal trefoil, oblique trefoil, horizontal coma, vertical coma, and spherical aberration values were measured using Scheimpflug corneal topography (Pentacam HR; Oculus Optikgeräte GmbH, Wetzler, Germany). Corneal densitometry values measured from 4 regions of the cornea (0–2, 2–6, 6–10, and 10–12 mm) and 4 corneal depths (anterior, central, posterior, and total) were recorded. Preoperative measurements of the patients (Group 1), postoperative first-month measurements (Group 2), and control group (Group 3) measurements were compared.Results:The total RMS measurement was 1.64±0.48 μm in Group 1, 1.35±0.32 μm in Group 2, and 1.17±0.38 μm in Group 3 (Group 1–2: p=0.007, Group 1–3: p<0.001, Group 2-3: p=0.173). The mean spherical aberration value was 0.183±0.057 μm in Group 1, 0.157±0.048 μm in Group 2, and 0.144±0.050 μm in Group 3 (Group 1–2: p=0.104, Group 1-3: p=0.004, Group 2–3: p=0.781). The total corneal densitometric measurement was 15.95±1.80 gray scale units (GSU) in Group 1, 14.76±1.76 GSU in Group 2, and 14.33±1.49 GSU in Group 3 (Group 1–2: p=0.01, Group 1–3: p<0.001, Group 2–3: p=0.804).Conclusion:It was observed that some corneal aberration and corneal densitometry values were higher in patients with a chalazion compared with those of healthy individuals, and there was a decrease in corneal aberration and densitometry values after surgical excision.

Evaluation of Corneal and Lenticular Parameters in Iron Deficiency Anemia.

Objectives:The aim of this study was to investigate the effects of iron deficiency anemia on corneal and lenticular densitometry.Methods:Thirty-two patients with iron deficiency anemia and 38 healthy participants were enrolled. The Pentacam HR imaging system (Oculus Optikgeräte GmbH, Wetzlar, Germany) was used to record keratometry, corneal densitometry (12-mm corneal diameter), lens densitometry measurements. Endothelial parameters were evaluated using specular microscopy.Results:The corneal densitometry values in the anterior 0–2 mm and 2–6 mm zone were significantly higher in the iron deficiency anemia group than in the control group (p=0.044 and p=0.021, respectively). There was a statistically significant difference in the mean values of the standard deviation and maximum lens densitometry measurements of the iron deficiency anemia group when compared with the control group (p=0.012 and p=0.011, respectively). There were statistically significant correlations between the anterior 2-6 mm zone corneal densitometry and ferritin, iron, and total iron binding capacity (r=-0.275, r=-0.243, r=0.240, respectively). However, ferritin, iron, and total iron binding capacity showed no significant correlation with the lens densitometry values (p>0.05 for all).Conclusion:Iron deficiency anemia had several effects on corneal and lenticular densitometry measurements. Evaluation of the corneal and lenticular changes at an ophthalmology clinic might be recommended for patients with iron deficiency anemia.

Evaluation of corneal safety in systemic lupus erythematosus patients undergoing long-term hydroxychloroquine treatment

Purpose The aim of this study was to examine the effects of long-term use of hydroxychloroquine (HQ) on the pachymetric, aberrometric, and densitometric values of the cornea and corneal endothelium in lupus patients. Method Twenty-two eyes (study group) of 22 patients using HQ for treatment of lupus and 25 eyes (control group) of 25 healthy individuals were included in this prospective study. A specular microscopy was used to measure corneal endothelial cell density (ECD), percentage of hexagonal cells (HEX%), coefficient of variation of the cell size (CV). Then, a Pentacam® HR corneal tomography system was used to measure central corneal thickness (CCT), corneal aberrometry values in 6-mm pupil diameters and corneal densitometry values in 6-mm corneal zones (0–2 mm and 2–6 mm). Results While ECD was significantly lower in the study group than in the control group (p = 0.034), CCT was significantly higher in the study group (p = 0.032). The higher-order aberrations values and the anterior corneal densitometry values in the 0–2 mm and 2–6 mm corneal zones in the study group were found to be significantly higher than the control group (p = 0.021, p = 0.007 and p = 0.013). Conclusion Prolonged use of HQ may cause some changes in the cornea. In the follow-up of these cases, detailed examination of the cornea as well as the macula may be important for the protection of corneal health.

Corneal densitometry: a potential indicator for early diagnosis of Fabry disease

PurposeTo assess corneal densitometry in patients with Fabry disease (FD) and to compare corneal densitometry differences in FD patients to different corneal manifestations.MethodsTen participants (20 eyes) with FD and 10 age-matched healthy volunteers (20 eyes) were recruited. All participants were assessed by standardized ophthalmic examinations and the corneal densitometry analysis by Pentacam HR. Densitometry measurements were analyzed in standardized grayscale units.ResultsSeven patients developed conjunctival vessel tortuosity, cornea verticillata appeared in 6 patients, and two patients had Fabry cataract. Retinal vessel tortuosity occurred in 4 patients, and dilation of retinal vessels appeared in 3 patients, all symptoms occurred in both eyes. The first diagnosis of FD up to examination was 4.7 ± 3.23 years, and first ERT up to examination was 2.6 ± 2.27 years. The initial time to diagnosis was negatively related to the corneal densitometry value of the 0–2-mm (r = − 0.556, p = 0.011) and 2–6-mm (r = − 0.482, p = 0.032) zones in the posterior layer. FD group have significantly higher corneal densitometry in anterior 0–2-mm zone and 2–10-mm zone anterior and posterior layer than the control group (p ≤ 0.035, respectively). When divided into two groups by the existence of cornea verticillata, there was a statistically significant difference in the anterior layer, 6–10-mm zone (p = 0.031); in the central layer, 0–2 mm (p = 0.012), 2–6 mm (p = 0.001), 6–10 mm (p = 0.002), and total (p = 0.002); and in the posterior layer, 6–10 mm (p = 0.004) and total (p = 0.002).ConclusionsFD patients show higher corneal densitometry, and corneal densitometry may have potential for early diagnosis and reminding progress of FD.

Comparison of Corneal Densitometry Between Penetrating Keratoplasty and Deep Anterior Lamellar Keratoplasty in Keratoconus Patients.

Our aim was to compare corneal densitometry values in keratoconic eyes undergoing deep anterior lamellar keratoplasty with the "big bubble" and manual lamellar dissection techniques, as well as penetrating keratoplasty. This retrospective study evaluated the postoperative outcomes of 31 eyes treated with big bubble-deep anterior lamellar keratoplasty, 23 eyes with manual lamellar dissectiondeep anterior lamellar keratoplasty, and 37 eyes with penetrating keratoplasty. Corneal densitometry, best corrected visual acuity, and other corneal tomographic parameters were recorded at 1, 6, 12, and 24 months postoperatively. The groups were compared with respect to the outcomes. There were no significant differences between the groups with respect to the anterior, central, and total corneal densitometry values at 0 to 2 mm and 2 to 6 mm. At 1 month postoperatively, the densitometric value in the posterior corneal layer of the 0- to 2-mm and 2- and 6-mm corneal zones was higher in the manual lamellar dissection-deep anterior lamellar keratoplasty group than in the big bubble-deep anterior lamellar keratoplasty and penetrating keratoplasty groups (P = .001). At 6, 12, and 24 months, the manual lamellar dissectiondeep anterior lamellar keratoplasty and penetrating keratoplasty groups had similar values in both zones in the posterior layer. The difference between manual lamellar dissection-deep anterior lamellar keratoplasty and big bubble-deep anterior lamellar keratoplasty in both zones in the posterior layer was statistically significant at 6, 12, and 24 months postoperatively (P < .05). The best corrected visual acuity of big bubble-deep anterior lamellar kerat oplasty and penetrating keratoplasty groups was better than that of the manual lamellar dissection-deep anterior lamellar keratoplasty group (P = .047). Corneal densitometry values may vary depending on the type of keratoplasty used in keratoconus patients. Higher densitometry values may affect visual quality in keratoplasty patients by decreasing or filtering the light that reaches the retina.

Pentacam corneal densitometry-guided treatment of adenoviral corneal subepithelial infiltrates: a comparative study between transepithelial phototherapeutic keratectomy and topical tacrolimus

To compare the changes in the measurement of corneal densitometry and total corneal higher-order aberrations (HOAs) between topical tacrolimus and transepithelial phototherapeutic keratectomy (Te-PTK) in the treatment of adenoviral corneal subepithelial infiltrates (SEIs). This is an interventional prospective randomized study, including 63 eyes of 35 patients with symptomatic adenoviral corneal SEIs for at least 6months. All patients underwent previous topical steroid therapy associated with unsatisfactory response and/or complications. Patients were assigned into three groups: (1) Te-PTK group: Te-PTK with MMC 0.02% was performed by a Technolas; Teneo excimer laser; (2) tacrolimus group: tacrolimus 0.03% ointment was applied once daily for 2-6months; the endpoint of treatment was based on the improvement in the corneal densitometry, BCVA, and OSDI; and (3) control group: no intervention was done. BCVA, corneal densitometry, and total corneal higher-order aberrations (HOAs) evaluation using Pentacam HR were done at the baseline, 1week, and then 1, 3, 6, and 12months of the study. The study population was similar between all groups. The mean follow-up was 12.75 ± 0.9months. Bilateral corneal SEI was recorded at 80%. At 12-month follow-ups, the mean BCVA improved in both the Te-PTK and tacrolimus groups without significant changes in the control group. The mean corneal densitometry of the anterior, central, and total cornea decreased significantly in the Te-PTK and tacrolimus groups. HO-RMS and total RMS decreased significantly in the Te-PTK and tacrolimus groups. BCVA, corneal densitometry (anterior, central, and total cornea), and corneal aberrations (total coma, total trefoil, HO-RMS, and total RMS) values were significantly better for the Te-PTK and tacrolimus groups than the control group. There were no statistically significant differences between Te-PTK and tacrolimus groups in terms of BCVA, corneal densitometry, corneal HOA, and the persistence of corneal SEIs. The persistence of corneal SEIs was significantly lower in Te-PTK and tacrolimus groups than the control group. Te-PTK and topical tacrolimus are effective methods for the treatment of adenoviral corneal SEIs improving visual acuity, corneal densitometry, and corneal HOA. The densitometry program of the Pentacam may give an objective guide for the treatment of adenoviral corneal SEIs. ClinicalTrials.gov ID is NCT04267991.

Objective evaluation of corneal and lens densitometry in children with Down syndrome

The goal of this study was to compare anterior segment topographic measurements and densitometry measurements of the cornea and lens of patients with Down syndrome (DS) with those of healthy individuals. Forty patients with DS (study group) and 43 healthy subjects (control group) were enrolled in this prospective study. Topographic measurements, including central corneal thickness (CCT), corneal volume (CV), anterior chamber depth, corneal densitometry (CD) and lens densitometry (LD) values, of the right eye of each participant were obtained. The CCT and CV values were significantly lower in the study group compared to those in the control group. The mean LD-horizontal, LD-vertical, LD-areal, three dimensional (3D), peak and CD values were higher in the patients with DS (5.90±0.7, 6.01±0.7, 5.61±0.54, 9.70±2.1, 20.94±7.53 and 15.61±1.34, respectively) than in the healthy control subjects (5.72±0.65, 5.83±0.60, 5.56±0.75, 8.63±1.83, 17.29±5.40 and 14.3±1.03, respectively) (LD-horizontal P=0.144, LD-vertical P=0.184, LD-areal P=0.743, 3D P=0.033, peak P=0.029 and CD P=0.001). The DS patients had higher CD and LD values. Additionally, the mean CCT and CV values in the DS group were less than those in the control group.

Analysis of Corneal Densitometry and Endothelial Cell Function in Fuchs Uveitis Syndrome.

To evaluate corneal densitometry and endothelial cell properties in patients with unilateral Fuchs uveitis syndrome (FUS), and to compare results with unaffected contralateral eyes and healthy control subjects. A total of 90 participants were included in this prospective cross-sectional study. Forty-five affected eyes of patients with FUS were regarded as group 1 (FUSa), 45 fellow eyes were regarded as group 2 (FUSf), and 45 healthy-control eyes were regarded as group 3. Corneal densitometry was measured with densitometry software of Scheimpflug Corneal Topography (Pentacam HR, Oculus GmbH, Wetzlar, Germany), whereas endothelial cell measurement was evaluated with specular microscopy (Tomey, EM4000, GmbH, Germany). The mean corneal densitometry values were higher in the midstromal (zones; 2-6, 6-10 mm), posterior (all zones), and total thickness (zones; 2-6, 6-10 mm) layers in the FUSa compared with FUSf and control eyes (P<0.05 for all comparisons). The mean values of average cell area and cell size characteristics (minimum, maximum, SD, and coefficient of variation) were higher; endothelial cell density and percentage of hexagonal cells were lower in the FUSa than in the other two groups (P<0.05 for all comparisons). There was a significantly strong correlation between specular microscopy parameters and posterior corneal densitometry values in the FUSa group. Impairment of endothelial cell function in affected eyes of patients with FUS resulted in increased values of corneal densitometry, especially posterior layer.