Comparison of central corneal thickness measurements with three new optical devices and a standard ultrasonic pachymeter

AIM:To compare the RTVue spectral optical coherence tomography(SD-OCT),Sirius Scheimpflug-Placido topographer,Lenstar optical low coherence reflectometry(OLCR)and ultrasound pachymetry(USP)devices in terms of their agreement and repeatability of measuring central corneal thickness(CCT).METHODS:In this prospective study,50 eyes of 50patients were included.Three repeated measures were obtained using SD-OCT,Scheimpflug-Placido topographer and USP and five measurements were determined with the OLCR.Bland-Altman plots were used to assess agreement among the instruments,and 95%limits of agreement(LoA)for each comparison were calculated.Intra-examiner repeatability was assessed using intraclass correlation coefficients(ICCs).RESULTS:The mean CCT by SD-OCT,ScheimpflugPlacido topographer,OLCR,and USP were 525.90±34.08μm,525.92±34.10μm,530.30±35.62μm,and543.50±37.11μm respectively.All 4 modalities of CCT measurements correlated closely with each other,with Pearson correlation coefficients ranging from 0.977 to0.995.The mean differences(and upper/lower LoA)for CCT measurements were-0.05±6.77μm(13.3/-13.3)between SD-OCT and Scheimpflug-Placido topographer,4.38±3.79μm(11.8/-3.1)between OLCR and SD-OCT,4.38±6.03μm(16.2/-7.5)between OLCR and ScheimpflugPlacido topographer,13.20±6.46μm(25.9/0.5)between USP and OLCR,17.59±6.76μm(30.8/4.3)between USP and SD-OCT,and 17.58±8.13μm(33.5/1.6)between USP and Scheimpflug-Placido topographer.Intra-examiner repeatability was excellent for all devices with ICCs】0.98.CONCLUSION:For most practical purposes,CCT measurements with the RTVue,Sirius and Lenstar can be used interchangeably.Although highly correlated,CCTmeasurement differences between USP and these 3optical instruments can be significant depending on the clinical situation.

Changes in intraocular pressure and central corneal thickness during pregnancy:a systematic review and Meta-analysis

AIM：To conduct a Meta-analysis for investigating the variations in intraocular pressure（IOP）and central corneal thickness（CCT）during normal pregnancy.METHODS：We searched for clinical trials published up to November 2015 without language or region restrictions in Pub Med,EMBASE,Web of Science,the Cochrane Central Register of Controlled Trials,Ovid,EBSCO,Elsevier,the Chinese Biomedicine Database,Wan Fang,CNKI,CQVIP and Google Scholar.Studies of the ocular changes observed in pregnant women were selected.The main outcomes were assessed by changes in IOP and CCT.RESULTS：Fifteen studies were included.In subgroup analyses,IOP was significantly decreased during the second MD=-1.53,95%CI（-2.19,-0.87）;P〈0.00001,and third MD=-2.91,95%CI（-3.74,-2.08）;P〈0.00001 trimesters of pregnancy.CCT was increased during the second MD=10.12,95%CI（2.01,18.22）;P=0.01,trimester of pregnancy;moreover,during the third trimester of pregnancy,the CCT displayed an increasing trend,but the difference was not significant MD=5.98,95%CI（-1.11,13.07）;P=0.1.CONCLUSION：A decrease in IOP is accompanied by an increase in CCT in the second and third trimesters of a normal pregnancy in women.

Corneal endothelial cell density and morphology and central corneal thickness in Guangxi Maonan and Han adolescent students of China

AIM: To investigate the corneal endothelial cell density and morphology and central corneal thickness in the Guangxi Maonan and Han adolescent students of China.METHODS: Noncontact specular microscope(Topcon SP3000 P, Tokyo, Japan) was performed in 133 adolescent students of Maonan nationality(M:F 54:79)and 105 adolescent students of Han nationality(M:F 50:55),5 to 20 y of age, who were randomly selected from 3schools in Huanjiang Maonan Autonomous County of Guangxi Zhuang Autonomous Region of China.Parameters studied included endothelial cell density,mean cell area, coefficient of variation in cell size,percentage hexagonality and central corneal thickness. RESULTS: Endothelial cell density, mean cell area,coefficient of variation in cell size, percentage hexagonality and central corneal thickness in the study population were(2969.50 ±253.93) cells/mm2,(339.23 ±29.44) μm2,(29.96 ±4.07) %,(64.58 ±9.41) % and(523.71 ±32.82) μm in Maonan and(2998.26 ±262.65) cells/mm2,(336.11±30.07) μm2,(29.89±5.03) %,(64.91±11.64) % and(524.39 ±33.15) μm in Han, respectively. No significant differences were observed in endothelial cell density,mean cell area, coefficient of variation in cell size,percentage hexagonality and central corneal thickness between Maonan and Han(P =0.615, 0.659, 0.528, 0.551,0.999). In Maonan and Han, we found age was negatively correlated with endothelial cell density and percentagehexagonality and positively correlated with mean cell area and coefficient of variation in cell size. Negative correlation was also found between central corneal thickness and age in Han, whereas no correlation was found in Maonan. CONCLUSION: There were no differences between Maonan and Han in corneal endothelial cell density and morphology and central corneal thickness. In these two nationalities, there were statistically significant decrease in endothelial cell density and percentage hexagonality with increasing age and statistically significant increase in cell area and coefficient of variation in cell size with increasing age. Central corneal thinned with increasing age in Han, whereas difference did not attain statistical significance in Maonan.

Monitoring of central corneal thickness after phacoemulsification—comparison of statical and rotating Scheimpflug pachymetry,and spectral-domain OCT

AIM:To explore the possibility of deploying three contactless devices(static and rotating Scheimpflug technology,spectral domain optical coherence tomography)for measuring central corneal thickness(CCT)in preoperative and postoperative examinations of cataract patients.METHODS:Totally 72 patients who had undergone surgery without complications were selected.The CCT was measured prior to the operation,as well as on the first,5th-7th and 28th day following the operation using the Nidek NT 530-P,Sirius?,and Topcon OCT-2000 devices.RESULTS:A significant postoperative increase and subsequent decrease in CCT was identified with all three devices.The correlations were highly significant and thus reflect a very good degree of comparability at all times with the exception of the rotating Scheimpflug camera.The postoperative results from the latter differed significantly from the other devices.The correlations were Sirius/Topcon(P=0.010)and Sirius/Nidek(P<0.0005).No statistically significant difference could be identified in the comparison between Topcon and Nidek(P=0.056).CONCLUSION:All three devices are suitable for postoperative monitoring of CCT.The measurement results are only comparable to a limited extent and not interchangeable in the course of treating a single patient.This is due to the different imaging technology used in the devices and the resulting modalities for conducting the measurements.

Measurement of central corneal thickness and precorneal tear film thickness of rabbits using the Scheimpflug system

AIMTo measure central corneal thickness (CCT) and pre-corneal tear film thickness using the Galilei dual-Scheimpflug analyzer (GSA) in New Zealand white rabbits.

Effect of silicone oil removal on central corneal thickness

AIM:To evaluate the effect of silicone oil removal(SOR) on central corneal thickness(CCT) in aphakic and pseudophakic eyes prospectively.· METHODS:Patients who underwent SOR surgery between June 2005-August 2007 were included in this study.Silicon oil was actively removed behind the posterior capsule through the pars plana sclerotomy site(posterior approach) in pseudophakic eyes and through the pupil and the corneal tunnel incision(anterior approach) in aphakic eyes with the 18-gauge cannula.CCT was assessed with Orbscan II corneal topography system preoperatively and at one month and three months postoperatively.A total of 34 eyes of 34 patients(26 males,8 females) comprised the study group.Mean age was(55.6±12.3) years(Range:25-80 years).Twenty-six eyes(76.5%) were pseudophakic and 8(23.5%) aphakic.Mean time between silicone oil injection and removal was(15.1±13.6) months(Range:5-54 months).At baseline,CCT was 576.4±46.0μm in pseudophakic eyes and 611.6±36.2μm in aphakic eyes.· RESULTS:At the first postoperative month CCT was(573.3±40.1)μm and(630.9±72.9)μm in pseudophakic and aphakic eyes respectively.At the third postoperative month,CCT was(582.7±49.5)μm and(614.5±82.4)μm in pseudophakic and aphakic eyes respectively.There was no statistically significant difference in CCT measurements one month and 3 months after SOR when compared to preoperative values in both aphakic and pseudophakic eyes(P> 0.05).· CONCLUSION:Active SOR either by anterior or posterior approach did not affect the CCT.·

Effect of 2% fluorescein on Scheimpflug central corneal thickness measurements

AIM： To assess central corneal thickness （CCT） changes measured with Scheimpflug device following instillation of 2% fluorescein in normal subjects. ~ METHODS： This was a prospective randomized study of 60 hospital volunteers. After baseline CCT measurements of both eyes of 40 subjects were obtained using Scheimpflug system, a drop of preservative-free 2% fluorescein, was instilled in one eye and in other eye, one drop of normal saline （control）. Measurements were repeated after 1, 2, 5, 10, 20, 30, 40, 50 and 60min （continuous assessment group）. Twenty subjects had baseline CCT taken, then fluorescein was instilled in one eye and measurements were taken at lmin. Ten eyes had saline rinse after lmin and 10 other eyes did not, measurements were repeated at 2min （eye rinse group）. RESULTS： The mean baseline CCT for continuous assessment group was 546.2±32.1um （range, 489.0-606.0）, control eyes was 546.6~±30.7 um （range, 489.0-602.0）. At lmin after fluorescein instillation, CCT significantly increased by 37.0±34.0um （P〈0.001）, then decreased gradually, reaching baseline at 60min. CCT variations were not significant in control group （P〉0.05）. For eye rinse group, CCT mean differences between baseline and 2min were 18.2um （95 % Ch -54.7 to 18.3） with rinse and 26.5um （95% CI： -62.9 to 9.9） without rinse; paired sample tests were not significant （P〉0.05）. CONCLUSION： The presence of fluorescein increased CCT value to a clinically relevant level of 6.8%. Eye rinse did not significantly reduce the effect at 2min post fluorescein timepoint.

Determination of Central Corneal Thickness in Patients with Refractive Anomalies and Emmetropy

Aim: The purpose of this study was to compare measurements of CCT in emmetropia and patient with refractive anomalies. Methods: We represent a retrospective research which was conducted at the University Clinical Center of Kosovo (UCCK). In this study were included 80 patients, divided into two groups: test and a control group. Mean age was (M = 25.90, DS = 7.16), men (N = 41% or 51.3%) and women (N = 39% or 48%). Results: Results show that there were no differences in the CCT, Hyperopic (M = 545.21 DS = 52.24), Myopic (M = 547.90 DS = 47.93) and Emmetropic (M = 550.75 DS = 41.29). After measuring of the longitudinal axis and analyzing the data by means of Anova test, it appeared to be a significant difference between the analyzed groups, Hyperopic (M = 21.99, DS = 1.27), Myopics (M = 23.21, DS = 1.24), Emmetropic (M = 22.36, DS = 0.81). Results also revealed that there is correlation between the CCT and IOP, where increase CCT decreases IOP and vice versa (r = -0.26, p = 0.01). Conclusion: The results have shown that CCT is thinner in myopic but does not show correlation with hypermetropic and emmetropic. While during the measurement of central corneal thickness and eye tension it is found that there is a negative correlation between them. Keratometry has a negative correlation with CCT. While there was no correlation between CCT and age. Given the role of CCT in interpreting IOP values, it is recommended to perform a systematic CCT measurement in routine clinical practice, which would assist in the diagnosis of ocular hypertension.

Distribution of central corneal thickness and intraocular pressure in emmetropic eyes of healthy children of Palestine: a representative cross-sectional study

AIM: To determine the distributions of central corneal thickness(CCT) and intraocular pressure(IOP) in emmetropic eyes of healthy children of Palestine.METHODS: This representative cross sectional study included a total of 1156 eyes from 578 healthy school children aged 7-15 y. Inclusion criteria included emmetropia, no previous history of ocular or systemic diseases, no previous history of contact lens use, and the availability of both eyes. CCT and IOP were measured using ultrasound pachymeter and Goldmann applanation tonometer, respectively. The relationship of the results with age and gender was investigated.RESULTS: The mean age of school children was 11.13±2.8 y. Mean CCT was 542.2±37.4 and 544.3±39.2 μm for right and left eyes, respectively. Mean IOP was 12.5±2.2 and 12.3±2.2 mm Hg for right and left eyes, respectively. A positive correlation was observed between CCT and IOP of the right eye(P<0.001, R=0.358) and CCT and IOP of the left eye(P<0.001, R=0.324). No significant differences were observed in CCT and IOP due to age or gender(P>0.05). There were significant differences in mean CCT and IOP between right and left eyes(P=0.004, P=0.001, respectively).CONCLUSION: A population profile of CCT and IOP is established in Palestinian children for the first time. Mean CCT is comparable to some studies but differ from others. Mean IOP is considerably lower than that of majority children of other ethnic groups. Intereye difference of more than 36 μm in CCT, and 5 mm Hg in IOP should prompt evaluation for potential ocular disorders.

The Influence of Central Corneal Thickness and Corneal Curvature and Axial Length on the Measurement of Intraocular Pressure

Purpose: To examine the influence of central corneal thickness (CCT), corneal curvature (CC), and axial length (AL) on intraocular pressure (IOP).Methods: Eighty-one clinically normal eyes were included in our study. The IOP, CCT, CC, AL were measured using a Goldmann applanation tonometer, optical pachymeter, keratometer and A-scan ultrasound biometer respectively in all subjects.Results: A highly significant positive correlation was identified between IOP and CCT. Linear regression analysis suggests that an increase in CCT of 0. 010 mm is associated with a 4. 946 mmHg increment in IOP. No significant positive correlation was identified between IOP and CC. P values are 0. 724 and 0.414 respectively for vertical and horizontal readings. A paradoxically reversed correlation was present between IOP and axial length.Conclusion: Corneal thickness is a very important confounding factor in the measurement of intraocular pressure, which warrants further attention in our clinical practice.

Comparison of Central Corneal Thickness using Ultrasound Pachymetry during Corneal Collagen Cross-linking

Purpose:To study variation in central corneal thickness (CCT) during corneal collagen cross-linking(CXL) using ultrasound pachymetry. Methods:Twenty patients (26 eyes) with progressing keratoconus undergoing riboflavin-UVA-induced CXL were involved in this study. Intraoperative CCT measurement using ultrasonic pachymetry was performed during the procedure.Measurements were obtained before operation, after epithelial removal, after riboflavin drop instillation, and after UVA irradiation. Results:Mean CCT was 495±56 and 450±52 μm before and after epithelial removal, respectively. Mean CCT was 443±42 and 411±39 μm after riboflavin drop instillation and after UVA irradiation, respectively. Statistically significant decreases in CCT occurred between the preoperative period and after epithelial removal, after riboflavin drop instillation and after UVA irradiation. Twenty-six eyes from 20 patients undergoing CXL were divided into 2 groups (I with CCT≥400 μm after UVA irradiation and II with CCT<400 μm after UVA irradiation). No statistically significant difference was noted between I and II in preoperative endothelial cell count, but a statistically greater postoperative endothelial cell count was noted in I compared to II. A statistically significant difference was evident between preoperative and postoperative endothelial cell counts in Group II (P<0.05). Conclusion:Performing CXL with the use of riboflavin and UVA irradiation resulted in a statistically significant decrease in CCT, to a level where the corneal endothelium may be damaged.(Eye Science 2013; 28:15-19)

Variation in Central Corneal Thickness during Open- or Closed-Eye Riboflavin Instillation for Corneal Collagen Cross-linking

Purpose:To assess the effect of having an open or closed eye on the variation in central corneal thickness during riboflavin instillation for corneal collagen cross-linking (CXL).Methods:.Thirty eyes of 15 New Zealand White rabbits underwent an in vivo anterior segment optical coherence tomography (OCT) examination at 0,10,20,and 30 min after riboflavin instillation on the de-epithelialized corneal surface.Each eye of every rabbit was randomly placed into one of two different treatment groups(open-eye or closed-eye)during the instillation;.the examinations were performed one after the other.After instillation for 30 min,the changes in the corneal stroma and anterior chamber were observed by slit lamp.Results:.A significant decrease in the central corneal thickness(CCT).was demonstrated during riboflavin instillation;.the variations were smaller in the measurements performed with the eye closed than with the eye open.(81.36±15.13μm and129.20±12.05μm respectively)..Both methods turned the corneal stroma and anterior chamber yellow.Conclusion:Keeping the eye closed during riboflavin instillation reduced the decrease in the CCT..The same yellow change in the corneal stroma and anterior chamber occurred,but the exposure time of the ocular surface was shorter.Therefore,.keeping the eye closed was a more effective and safer method than keeping the eye open.

Central Corneal Thickness of Diabetic Patients in Yaoundé: Case Control Study

Background: To compare central corneal thickness (CCT) values measured in diabetic eyes and compare the CCT values in normal patients without diabetes. Methods: A total of 83 diabetic patients and 83 non-diabetic patients were prospectively enrolled in this comparative case series. CCT was measured using a Topcon CT-1P non-contact automated pachymeter, and values were compared. Results: Mean age was 57 ± 11 years, with a range of 23 and 80 years. The mean CCT was 508.87 ± 35.83 μm for diabetic patients and 513.41 ± 37.22 μm for non-diabetic patients. There was no statistically significant difference between the CCT of diabetic patients compared to non-diabetic patients (p = 0.260). We did not find a significant correlation between the CCT of diabetic patients and clinical characteristics of diabetes. However, there was a positive and statistically significant linear correlation between the CCT of diabetic patients and intra ocular pressure (IOP). Conclusion: The mean CCT in diabetic patients was lower than in non-diabetic control patients, although there was no statistically significant difference.

Changes of corneal central thickness of aphakia following congenital cataract surgery under the first six months of life

AIM: To observe the central corneal thickness (CCT) changes in infants and young children who had been undergone bilateral congenital cataract surgery, and to compare the changes with normal control group which was selected from healthy population. METHODS: A cross section case-control study contained 28 cases (56 eyes) of bilateral aphakia (aphakic group) due to congenital cataract surgery combining with posterior continuous curvilinear capsulorhexis and with anterior vitrectomy during 2-6 months after birth. Fourteen children (28 eyes) of age-sex matched with the aphalic group were selected as normal control group. CCT and intraocular pressure (TOP) were measured postoperatively and the results were compared between groups. RESULTS: The mean CCT was 653.5 +/- 82.4 mu m in the aphakic group and 579.6 +/- 39.2 mu m in the control group, with a significant difference (P=0.000). The mean value of TOP in aphakic group (22.0 +/- 1.6mmHg) was greater than that of control group (16.9 +/- 2.1mmHg), P=0.023. There was a negative correlation between age and CCT in normal control group (r=-0.531, P=0.026), and there was no correlation in bilateral aphakia group (r=-0.324, P=0.165). CONCLUSION: Aphakic children due to congenital cataract surgery have a greater CCT than normal children. It is necessary to consider CCT in evaluating IOP for children after congenital cataract surgery.

Central corneal thickness measurements in premature infants

AIM:To evaluate the central corneal thickness(CCT)measurements of premature infantsMETHODS:The premature infants who were born between 25-34wk of gestational age(GA)were retrieved for the study.All CCT measurements were performed within the first 2d of their life under topical anesthesia by using an ultrasonic pachymeter.RESULTS:The mean CCT of 200 eyes was 647.79±63.94μm.The mean CCT of the right and left eyes were similar(647.30±64.72μm and 648.29±63.47μm consecutively).The mean CCT of the girls was 642.08±54.89μm and the boys was 653.07±71.14μm,with no statistically significant difference(P】0.05).But there was a negative correlation of the CCT with GA and birth weight(BW)(P【0.01).CONCLUSION:The CCT values of premature babies were negatively correlated with GA and BW.

Central Corneal Thickness in Adult Chinese

The central corneal thickness （CCT） in age 48 years or less of Chinese was characterized and its relationship with gender, age, refraction and intraocular pressure （IOP） was investigated. Right eyes of 1669 participants were included in this study （880 men, 52.7 % and 789 women, 47.3 %）. Mean age of the samples was 23.8±5.9 years. After the examination of corneal topography and refraction, Goldman applanation tonometry was carried out by one physician. Tonometric values were the mean of three consecutive readings. Subsequently, another physician carried out ultrasonic pachymetry with the DGH 2000 AP ultrasonic pachymeter. Six measurements were made at the center of the cornea of each eye. The mean value was used for analysis. The results showed that mean CCT of male participants was 551.33±34.62 μm, 5.79μm more than that of female participants. Linear regression analyses revealed that CCT was negatively related with age only in female and no association was found between refractive status and CCT. IOP was positively related to CCT, and there was a difference in IOP of 1.5 mmHg （1 mmHg=0. 133 kPa） per 100 μm difference in CCT. Ocular hypertension group was prone to have thicker cornea than average. The results indicated that in adult Chinese CCT tended to decrease with aging in female only. IOP measured by Goldmann tonometry was positively related with CCT so that CCT should be measured a- long with IOP.

Sirius Scheimpflug-Placido versus. ultrasound pachymetry for central corneal thickness: meta-analysis

Background:To compare the difference in central corneal thickness(CCT)measurements in normal eyes between a rotating Scheimpflug camera combined with a Placido-disk corneal topographer(Sirius,CSO,Italy)and ultrasound pachymetry(USP).Methods:A systematic literature search was conducted for relevant studies published on PubMed,Medline,EMBASE,and the Cochrane Library and ClinicalTrials.gov from inception to August 1st,2019.Primary outcome measures were CCT measurements between Sirius and USP.A random effects model was used to pool CCT measurements.Results:A total of twelve studies involving 862 eyes were included in this meta-analysis.The meta-analysis found CCT measurements between Sirius and USP to be statistically significantly different(P<0.0001).The mean difference between Sirius and USP was-11.26μm with a 95%confidence interval(CI)(-16.92μm,-5.60μm).The heterogeneity Was IP=60%(P=0.004).Conclusion:CCT measurements with the Sirius Scheimpflug-Placido topographer were statistically significantly lower than USP.However,it may be argued that the mean difference of 11.26μm is not a clinically significant difference.

Detection of macular ganglion cell complex loss and correlation with choroidal thickness in chronic and recurrent central serous chorioretinopathy

AIM:To investigate the association of ganglion cell complex thickness(GCCt),global loss volume percentage(GLV%),and focal loss volume percentage(FLV%)with structural and functional findings among patients with chronic central serous chorioretinopathy(CCSC)and recurrent central serous chorioretinopathy(RCSC)by optical coherence tomography(OCT).METHODS:Among 29 patients with monocular affected central serous chorioretinopathy(CSC),15 had CCSC,and 14 had RCSC.The GCCt,FLV%,GLV%,and subfoveal choroidal thickness(SFCT)and sublesional choroidal thickness(SLCT)values were determined using OCT,and the association of these characteristics with neural structure parameters,choroidal morphology,features and functional alterations were estimated for the CCSC and RCSC patients.RESULTS:In CCSC,the affected eyes had significantly lower GCCt values than the fellow eyes in the macular regions(all P<0.05),with the highest GCCt observed in the inferior area.A significant association was found between the GCCt in different regions and the change in best corrected visual acuity(BCVA;r=-0.696;-0.695;-0.694,P<0.05)in CCSC patients.A statistically significant moderate negative correlation indicated that long-term CCSC was associated with greater differences in the GCCt in different regions between affected and fellow eyes(r=-0.562;r=-0.556;r=0.525,P<0.05).Additionally,observation of thickened SFCT was associated with a worse FLV%(r=0.599;r=0.546,P<0.05)in both groups.Similarly,thickened SLCT was associated with FLV%in RCSC patients(r=0.544,P<0.05).CONCLUSION:The distribution and GCCt are associated with the duration and visual outcomes of CCSC,whereas there is no correlation among RCSC patients.FLV%may be instrumental in differentiating the various outer choroidal vessels(pachyvessels)in long-term CSC.These results suggest that neural structure parameters may aid in estimating and predicting the recovery of altered morphology and function in CCSC and RCSC patients.

The Mean Central Cornea Thickness and Associated Factors among Adult Patients Attending Mulago Hospital Eye Clinic Kampala, Uganda

Background: The mean central corneal thickness (CCT) values are known to have an influence on intraocular pressure measurement and vary widely with age, sex and ethnicity. Little is known about the pattern of CCT in central Uganda. Aim: To determine the mean central corneal thickness and its associated factors among adult patients attending Mulago Hospital eye clinic, Kampala Uganda. Design and Method: A cross sectional study was done from August to October 2016 on 270 adult patients selected by systemic random sampling. The study included all adult patients who attended the eye clinic during the study period and consented to the study excluding those who had conditions causing abnormal thinning, thickening or irregularity of the cornea. The participants were evaluated by history taking and ocular examination including visual acuity assessment, slit lamp examination, central cornea thickness measurement, intraocular pressure measurement and funduscopy. Data were collected using a pretested questionnaire, entered using Epidata and analyzed by STATA11.0. Results: Of the 270 patients examined, 61% were female, 39% male, the mean age being 42 years ranging from 18 to 96 years. The mean central corneal thickness for both eyes was 539.3 (SD ± 41.65 μm) ranging from 332 μm to 701 μm and mean intraocular pressure was 15 (SD ± 5.34) mmHg. Gender, ethnicity, IOP, glaucoma, hypertension, diabetes, refractive error, were not statistically significantly associated with central cornea thickness. However central cornea thickness was statistically significantly associated with systolic blood pressure (r = -0.24, p = 0.025) and age (p = 0.002). A one-year increase in age reduced the mean central cornea thickness by 0.54 μm. Conclusion: The average CCT of Ugandan adult population was 539.3 ± 41.65 μm which falls in the category of normal central cornea thickness. Central corneal thickness reduced with increasing age and increasing systolic blood pressure.

Manifestations of type 2 diabetes in corneal endothelial cell density,corneal thickness and intraocular pressure

We sought to evaluate central corneal thickness（CCT）,corneal endothelial cell density（ECD）and intraocular pressure（IOP）in patients with type 2 diabetes mellitus（DM）and to associate potential differences with diabetes duration and treatment modality in a prospective,randomized study.We measured ECD,CCT and IOP of125 patients with type 2 DM（mean age 57.1±11.5 years）and compared them with 90 age-matched controls.Measured parameters were analyzed for association with diabetes duration and glucose control modalities（insulin injection or oral medication）while controlling for age.In the diabetic group,the mean ECD（2511±252 cells/mm^2）,mean CCT（539.7±33.6μm）and mean IOP（18.3±2.5 mmHg）varied significantly from those the control group[ECD：2713±132 cells/mm^2（P〈0.0001）,CCT：525.0±45.3μm（P=0.003）and IOP：16.7±1.8 mmHg（P〈0.0001）].ECD was significantly reduced by about 32 cell/mm^2 for diabetics with duration of〉10 years when compared with those with duration of〈10 years（P〈0.05）.CCT was thicker and IOP was higher for diabetics with duration of〉10 years than those with duration of〈10 years（P〉0.05）.None of the measured parameters was significantly associated with diabetes duration and treatment modality（P〉0.05）.In conclusion,subjects with type 2DM exhibit significant changes in ECD,IOP and CCT,which,however,are not correlated with disease duration or if the patients receive on insulin injection or oral medications.