A prediction model for classifying maternal pregnancy smoking using California state birth certificate information.

BACKGROUND: Systematically recorded smoking data are not always available in vital statistics records, and even when available it can underestimate true smoking rates. OBJECTIVE: To develop a prediction model for maternal tobacco smoking in late pregnancy based on birth certificate information using a combination of self- or provider-reported smoking and biomarkers (smoking metabolites) in neonatal blood spots as the alloyed gold standard. METHODS: We designed a case-control study where childhood cancer cases were identified from the California Cancer Registry and controls were from the California birth rolls between 1983 and 2011 who were cancer-free by the age of six. In this analysis, we included 894 control participants and performed high-resolution metabolomics analyses in their neonatal dried blood spots, where we extracted cotinine [mass-to-charge ratio (m/z) = 177.1023] and hydroxycotinine (m/z = 193.0973). Potential predictors of smoking were selected from California birth certificates. Logistic regression with stepwise backward selection was used to build a prediction model. Model performance was evaluated in a training sample, a bootstrapped sample, and an external validation sample. RESULTS: Out of seven predictor variables entered into the logistic model, five were selected by the stepwise procedure: maternal race/ethnicity, maternal education, child's birth year, parity, and child's birth weight. We calculated an overall discrimination accuracy of 0.72 and an area under the receiver operating characteristic curve (AUC) of 0.81 (95% confidence interval [CI] 0.77, 0.84) in the training set. Similar accuracies were achieved in the internal (AUC 0.81, 95% CI 0.77, 0.84) and external (AUC 0.69, 95% CI 0.64, 0.74) validation sets. CONCLUSIONS: This easy-to-apply model may benefit future birth registry-based studies when there is missing maternal smoking information; however, some smoking status misclassification remains a concern when only variables from the birth certificate are used to predict maternal smoking.

Cytoplasmic synthesis of endogenous Alu complementary DNA via reverse transcription and implications in age-related macular degeneration.

Alu retroelements propagate via retrotransposition by hijacking long interspersed nuclear element-1 (L1) reverse transcriptase (RT) and endonuclease activities. Reverse transcription of Alu RNA into complementary DNA (cDNA) is presumed to occur exclusively in the nucleus at the genomic integration site. Whether Alu cDNA is synthesized independently of genomic integration is unknown. Alu RNA promotes retinal pigmented epithelium (RPE) death in geographic atrophy, an untreatable type of age-related macular degeneration. We report that Alu RNA-induced RPE degeneration is mediated via cytoplasmic L1-reverse-transcribed Alu cDNA independently of retrotransposition. Alu RNA did not induce cDNA production or RPE degeneration in L1-inhibited animals or human cells. Alu reverse transcription can be initiated in the cytoplasm via self-priming of Alu RNA. In four health insurance databases, use of nucleoside RT inhibitors was associated with reduced risk of developing atrophic macular degeneration (pooled adjusted hazard ratio, 0.616; 95% confidence interval, 0.493-0.770), thus identifying inhibitors of this Alu replication cycle shunt as potential therapies for a major cause of blindness.

Exposure to nitrosatable drugs during pregnancy and childhood cancer: A matched case-control study in Denmark, 1996-2016.

BACKGROUND: Nitrosatable drugs can be synthesized to N-nitroso compounds in human stomach. In a pregnant woman, N-nitroso compounds can be translocated to the fetus through the placenta. Maternal exposure of nitrosatable compounds during pregnancy has been associated with childhood brain tumors and leukemia. However, few studies have investigated an association between nitrosatable drug exposure during pregnancy and childhood cancer. We examined if maternal prescriptions of nitrosatable drugs received during pregnancy are associated with childhood cancer. METHODS: A matched case-control study was conducted using Danish nationwide registry data from 1995 to 2016. Each childhood cancer case was matched with twenty-five controls. Maternal exposure of nitrosatable drugs during pregnancy was identified from the Danish National Prescription Register. A multivariable conditional logistic regression model was used to estimate adjusted odds ratios (adj.OR) with 95% confidence intervals (CI) for each childhood cancer type. RESULTS: Maternal prescriptions of nitrosatable drugs positively associate with central nervous system tumors (adj.OR = 1.25; 95% CI = 1.04-1.51) and neuroblastoma (adj.OR = 1.96; 95% CI = 1.34-2.85) in offspring. We also observed a positive association between perinatal exposure of nitrosatable drugs and acute lymphoblastic leukemia (adj.OR = 1.31; 95% CI = 1.07-1.59), however, it appeared to be due to confounding by indication, i.e., maternal infections. CONCLUSION: Nitrosatable drug use during pregnancy potentially increased risk of central nervous system tumors and neuroblastoma. While a positive association between maternal prescriptions of nitrosatable drugs and acute lymphoblastic leukemia should be interpreted cautiously because of confounding by indication.

BIOMARKERS OF MATERNAL SMOKING AND THE RISK OF RETINOBLASTOMA IN OFFSPRING.

PURPOSE: Previous studies examining the risk of retinoblastoma with maternal smoking were inconclusive, likely due in part to the reliance on self-reported maternal smoking. This study uses biomarkers of tobacco smoking in neonatal dried blood spots to investigate associations between maternal smoking and retinoblastoma in offspring. METHODS: The authors randomly selected 498 retinoblastoma cases and 895 control subjects born between 1983 and 2011 from a population-based case-control study in California. Maternal pregnancy-related smoking was measured using the following three metrics: provider or self-reported smoking during pregnancy, cotinine, and hydroxycotinine in neonatal blood. The authors used multivariable logistic regression to estimate the effects of maternal tobacco smoking on retinoblastoma. RESULTS: Using all metrics (biomarkers or self-report), maternal smoking late in pregnancy or early postpartum was related to retinoblastoma (all types; odds ratio = 1.44, 95% confidence interval: 1.00-2.09). Relying on cotinine or hydroxycotinine to ascertain smoking, maternal smoking was related to unilateral retinoblastoma (odds ratio = 1.66, 95% confidence interval: 1.08-2.57). CONCLUSION: The results indicate that maternal smoking during pregnancy may be a risk factor for retinoblastoma, particularly among unilateral cases.

Maternal diabetes and childhood cancer risks in offspring: two population-based studies.

BACKGROUND: The effect of maternal diabetes on childhood cancer has not been widely studied. METHODS: We examined this in two population-based studies in Denmark (N = 6420 cancer cases, 160,484 controls) and Taiwan (N = 2160 cancer cases, 2,076,877 non-cases) using logistic regression and Cox proportional hazard regression adjusted for birth year, child's sex, maternal age and birth order. RESULTS: Gestational diabetes in Denmark [odds ratio (OR) = 0.98, 95% confidence interval (CI): 0.71-1.35] or type II and gestational diabetes in Taiwan (type II: hazard ratio (HR) = 0.81, 95% CI: 0.63-1.05; gestational diabetes: HR = 1.06, 95% CI: 0.92-1.22) were not associated with cancer (all types combined). In Denmark, maternal type I diabetes was associated with the risk of glioma (OR = 2.33, 95% CI: 1.04-5.22), while in Taiwan, the risks of glioma (HR = 1.59, 95% CI: 1.01-2.50) were elevated among children whose mothers had gestational diabetes. There was a twofold increased risk for hepatoblastoma with maternal type II diabetes (HR = 2.02, 95% CI: 1.02-4.00). CONCLUSIONS: Our results suggest that maternal diabetes is an important risk factor for certain types of childhood cancers, emphasising the need for effective interventions targeting maternal diabetes to prevent serious health effects in offspring.

OCT Risk Factors for Development of Late Age-Related Macular Degeneration in the Fellow Eyes of Patients Enrolled in the HARBOR Study.

PURPOSE: To evaluate the relationship between OCT features and progression to late age related-macular degeneration (AMD) in the fellow eyes of patients enrolled in the Study of Ranibizumab Administered Monthly or on an As-needed Basis in Patients With Subfoveal Neovascular AMD (HARBOR) (ClinicalTrials.gov identifier, NCT00891735). DESIGN: Post hoc analysis of a phase 3 multicenter, prospective, randomized, double-masked, active treatment-controlled clinical trial. PARTICIPANTS: Evaluable patients (n = 501) with macular neovascularization (MNV) secondary to neovascular AMD and early or intermediate AMD in the fellow eye. METHODS: Volume OCT scans from 501 fellow eyes of 501 patients with MNV were reviewed. Baseline OCT features that were assessed included intraretinal hypereflective foci (IHRF), hyporeflective foci (hRF) within drusenoid lesions (DLs), subretinal drusenoid deposits (SDDs), and drusen volume (DV) of 0.03 mm3 or more. OCT images obtained at months 6, 12, 18, and 24 were graded by masked graders for late AMD (defined as MNV, complete retinal pigment epithelium and photoreceptor atrophy [cRORA], or both). Participant demographic characteristics (age, gender, and smoke exposure) and baseline OCT features were correlated with progression to late AMD. MAIN OUTCOME MEASURES: Incidence of late AMD, hazard ratio (HR) for demographics, and OCT risk factors. RESULTS: At month 24, 33.13% of eyes (166/501) demonstrated late AMD: 20.96% (105/501) demonstrated cRORA, whereas 12.18% (61/501) demonstrated MNV. Baseline demographic factors were not associated significantly with development of late AMD, whereas significant associations were identified for all OCT features. Intraretinal hypereflective foci had an HR of 5.21 (95% confidence interval [CI], 3.29-8.26), hRF within DLs had an HR of 2.42 (95% CI, 1.74-3.38), SDD had an HR of 1.95 (95% CI, 1.34-2.82), and DV of 0.03 mm3 or more had an HR of 1.46 (95% CI, 1.03-2.07). The correlation remained significant when considering only the progression to cRORA and MNV alone, except for DV, which was not associated significantly with progression to MNV. CONCLUSIONS: We confirmed that 4 previously reported OCT risk factors were associated with progression to late AMD in the fellow eyes of patients newly diagnosed with MNV. Although outcomes of more than 2 years were not evaluated, these findings may help to identify high-risk AMD patients.

Increasing Prescription Opioid and Heroin Overdose Mortality in the United States, 1999-2014: An Age-Period-Cohort Analysis.

OBJECTIVES: To assess cohort effects in prescription opioid and heroin overdose mortality in the United States. METHODS: Using the National Center for Health Statistics' multiple-cause-of-death file for 1999 to 2014, we performed an age-period-cohort analysis of drug overdose mortality in the United States. RESULTS: Compared with those born in 1977 and 1978, individuals born between 1947 and 1964 experienced excess risks of prescription opioid overdose death (e.g., for the 1955-1956 birth cohort, rate ratio [RR] = 1.27; 95% confidence interval [CI] = 1.09, 1.48) and of heroin overdose death (e.g., for the 1953-1954 birth cohort, RR = 1.32; 95% CI = 1.11, 1.57). Those born between 1979 and 1992 also experienced an increased risk of heroin overdose death (e.g., for the 1989-1990 birth cohort, RR = 1.23; 95% CI = 1.01, 1.50). The cohort effects were consistent between sexes. CONCLUSIONS: Individuals born between 1947 and 1964 and between 1979 and 1992 are particularly afflicted by the opioid epidemic. Intervention programs are needed to reduce the excess overdose mortality in these specific demographic groups.

Resveratrol Ameliorates Pressure Overload-induced Cardiac Dysfunction and Attenuates Autophagy in Rats.

Pressure overload has an important role in heart failure, inducing excessive autophagy in cardiac myocytes that is considered to be pathogenic. Resveratrol has been reported to improve cardiac dysfunction induced by pressure overload, but it has been unclear whether resveratrol ameliorates cardiac dysfunction by regulating autophagy. In this study, heart failure was induced in rats by constriction of the abdominal aorta. Four weeks after surgery, the rats with heart failure were randomized to treatment with resveratrol (8 mg · kg(-1) · d(-1) by intraperitoneal injection) for 28 days or to intraperitoneal injection of the vehicle (propylene glycol) alone. Echocardiography was performed to assess cardiac function. Expression of brain natriuretic peptide messenger RNA in the left ventricle was detected by real-time polymerase chain reaction, whereas expression of proteins associated with autophagy (beclin-1 and lamp-1) was detected by western blotting and immunohistochemistry. Furthermore, autophagic vacuoles were detected in the heart by transmission electron microscopy, and the myocardial ATP content was measured by the bioluminescence method. Treatment with resveratrol significantly improved cardiac dysfunction and reduced brain natriuretic peptide expression in rats with heart failure. Resveratrol down-regulated beclin-1 and lamp-1 expression and also inhibited the formation of autophagic vacuoles in failing hearts. Furthermore, resveratrol restored the myocardial ATP level and reduced phosphorylation of AMP-activated protein kinase at Thr172. These results suggest that resveratrol may inhibit autophagy through inactivation of AMP-activated protein kinase and restoration of ATP in heart failure induced by pressure overload. Accordingly, resveratrol may be beneficial for patients with hypertensive heart disease.

Regulation of pepc gene expression in Anabaena sp. PCC 7120 and its effects on cyclic electron flow around photosystem I and tolerances to environmental stresses.

Since pepc gene encoding phosphoenolpyruvate carboxylase (PEPCase) has been cloned from Anabaena sp. PCC 7120 and other cyanobacteria, the effects of pepc gene expression on photosynthesis have not been reported yet. In this study, we constructed mutants containing either upregulated (forward) or downregulated (reverse) pepc gene in Anabaena sp. PCC 7120. Results from real-time quantitative polymerase chain reaction (RT-qPCR), Western blot and enzymatic analysis showed that PEPCase activity was significantly reduced in the reverse mutant compared with the wild type, and that of the forward mutant was obviously increased. Interestingly, the net photosynthesis in both the reverse mutant and the forward mutant were higher than that of the wild type, but dark respiration was decreased only in the reverse mutant. The absorbance changes of P700 upon saturation pulse showed the photosystem I (PSI) activity was inhibited, as reflected by Y(I), and Y(NA) was elevated, and dark reduction of P700(+) was stimulated, indicating enhanced cyclic electron flow (CEF) around PSI in the reverse mutant. Additionally, the reverse mutant photosynthesis was higher than that of the wild type in low temperature, low and high pH, and high salinity, and this implies increased tolerance in the reverse mutant through downregulated pepc gene.

Recombinant expression and functional analysis of a Chlamydomonas reinhardtii bacterial-type phosphoenolpyruvate carboxylase gene fragment.

To investigate the function of a bacterial-type phosphoenolpyruvate carboxylase (PEPC2) derived from photosynthetically-grown Chlamydomonas reinhardtii, a fragment of the pepc2 gene was cloned and expressed in Escherichia coli. After optimal induction for 6 h, PEPC activity in the reverse mutant was lower than wild type (0.9 vs. 1.7 U/mg protein), and soluble protein was also lower than wild type (119 vs. 186 mg/g dry wt). In contrast, the total lipid content was increased from 56 (in wild type) to 71 mg/g dry wt, despite the growth rate being slightly diminished. The changes in PEPC activity, soluble protein and total lipid in the forward mutant were the opposite (2.4 U/mg, 230 mg/g, and 44 mg/g dry wt, respectively). Together, these data indicate that PEPC may function as a metabolic pivot in the regulation of protein and lipid accumulation in this alga.

Maternal anemia and childhood cancer: a population-based case-control study in Denmark.

BACKGROUND: Childhood cancer risk is associated with maternal health during pregnancy. Anemia in pregnancy is a common condition, especially in low-income countries, but a possible association between maternal anemia and childhood cancer has not been widely studied. METHODS: We examined the relation in a population-based study in Denmark (N = 6420 cancer cases, 160,485 controls). Cases were taken from the Danish Cancer Registry, and controls were selected from national records. We obtained maternal anemia diagnoses from the National Patient and Medical Births registries. In a separate analysis within the years available (births 1995-2014), we examined cancer risks among mothers taking prescribed vitamin supplements, using data from the National Prescription Register. We estimated the risks of childhood cancer using conditional logistic regression. RESULTS: The risks of neuroblastoma [odds ratio (OR= 1.83, 95% confidence interval (CI): 1.04, 3.22] and acute lymphoblastic leukemia (OR= 1.46, 95% CI 1.09, 1.97) were increased in children born to mothers with anemia in pregnancy. There was a two-fold increased risk for bone tumors (OR= 2.59, 95% CI: 1.42, 4.72), particularly osteosarcoma (OR= 3.54, 95% CI 1.60, 7.82). With regards to prescribed supplement use, mothers prescribed supplements for B12 and folate deficiency anemia (OR= 4.03, 95% CI 1.91, 8.50) had an increased risk for cancer in offspring. CONCLUSION: Our results suggest that screening for anemia in pregnancy and vitamin supplementation may be an actionable strategy to prevent some cases of childhood cancer.

Danish Population Based Study of Familial Epilepsy and Childhood Cancer.

Objective: Results from studies investigating the association between maternal or child epilepsy, use of anticonvulsants in pregnancy, and childhood cancer are inconsistent and at times contradictory. Methods: Linking Danish national databases, we obtained epilepsy and childhood cancer diagnoses, and anticonvulsant use data. We estimated adjusted odds ratios of all or specific childhood cancers in relation to maternal or child epilepsy and anticonvulsant therapies using conditional logistic regression. Results: Maternal epilepsy was positively associated with all childhood cancers in offspring, specifically, with acute lymphoblastic leukemia (Odds Ratio (OR) = 1.68, 95% Confidence Interval (CI) = 1.16, 2.43) and Wilms tumor (OR = 2.13, 95%CI = 0.97, 4.68). When considering maternal ever (lifetime) ingestion of anticonvulsants, a positive association was found with all cancers (OR = 1.15, 95%CI = 1.01, 1.31), and central nervous system tumors (OR = 1.32, 95%CI = 1.03, 1.69) as well as neuroblastoma (OR = 2.05, 95%CI = 1.29, 3.28) among offspring. Maternal anticonvulsant use before or during the index pregnancy was related to CNS tumors in offspring (OR = 1.78, 95%CI = 0.99, 3.21), however the confidence interval included the null. Significance: Maternal use of certain anticonvulsant medications may be a risk factor for cancer in offspring. Medical providers may need to consider what type of treatments to prescribe to pregnant mothers with epilepsy.

Metabotropic glutamate receptor 5 upregulation of γ-aminobutyric acid transporter 3 expression ameliorates cognitive impairment after traumatic brain injury in mice.

Traumatic brain injury (TBI) causes neurotransmitter disturbances contributing to neuronal cell death and neurological deficits. In humans, brain injuries impair γ-aminobutyric acid (GABA) uptake and ultimately result in cognitive impairment. GABA transporter 3 (GAT3) is a vital approach of GABA reuptake and catabolism. The contribution of GAT3 in TBI-induced cognitive impairment and its underlying mechanisms remain unknown, which were explored in the present study. Here, we found that expression of GAT3 was downregulated to increase GABA concentration in the mouse brain after TBI. And GAT3 was detected in neurons and astrocytes after TBI unexpectedly, instead of merely expressed on astrocytes in physiological states. Subsequently, activated metabotropic glutamate receptor 5 (mGluR5) reduced GABA content by elevating the expression levels of GAT3. Then, increased mGluR5 activity obviously improved cognitive impairment. Mechanistically, mGluR5 was activated to evidently induce the expression of p-ERK, CREB, and p-CREB after TBI. The inhibition of CREB decreased the expression of CREB, p-CREB, and GAT3 elevated by active mGluR5. However, the CREB inhibitor increased GABA content. Furthermore, Rab11a regulating GAT3 trafficking by endocytosis was elevated after TBI. And Rab11a downregulated by active mGluR5 was reversed by CREB inhibitor. In summary our findings elucidated that activated mGluR5 ameliorated cognitive function by upregulating GAT3 in TBI. And mGluR5 possibly regulated GAT3 by ERK/CREB/Rab11a pathway. GAT3 could serve as a potential target for TBI cognitive treatment.

Cohort study of familial viral hepatitis and risks of paediatric cancers.

BACKGROUND: Although viral hepatitis causes paediatric hepatocellular carcinoma and hepatic and extrahepatic cancers in adults, there are few epidemiologic studies on paediatric-cancer risks from parental viral hepatitis. In a nationwide study in a viral hepatitis endemic region and with confirmation in another population-based sample, we examined associations between parental hepatitis B (HBV) and C (HCV) infections and risks of cancers in offspring. METHODS: We included all children born in Taiwan in 2004-2014 (N = 2 079 037) with 2160 cancer cases ascertained from the Cancer Registry. We estimated risks for paediatric cancers using Cox proportional-hazard regressions. We checked these associations in a nationwide case-control study in Denmark (6422 cases, 160 522 controls). RESULTS: In Taiwan, paternal HBV was related to child's hepatoblastoma [hazard ratio (HR) = 1.77, 95% confidence interval (CI) = 1.05, 2.97] when identified at any time in the medical record, and when analyses were limited to hepatitis diagnoses occurring before the child's birth, risks increased (HR = 2.08, 95% CI = 1.13-3.80). Paternal HCV was related to child's non-Hodgkin lymphoma (HR = 2.06, 95% CI = 1.13-3.74). Maternal HCV was weakly related to increased risks of all childhood cancers [all types combined; HR = 1.45, 95% CI = 0.95-2.22]. The population-attributable fraction of hepatoblastoma for maternal, paternal and child HBV was 2.6%, 6.8% and 2.8%, respectively. CONCLUSIONS: Parental HBV and HCV may be risk factors for hepatic and non-hepatic cancers in children. If associations are causal, then parental screening and treatment with antivirals may prevent some paediatric cancers.

Diagnostic values of MMP-7, MMP-9, MMP-11, TIMP-1, TIMP-2, CEA, and CA19-9 in patients with colorectal cancer.

OBJECTIVE: Colorectal cancer (CRC) is one of the most common and lethal malignancies. The identification of precise and noninvasive biomarkers is urgently needed to aid the early diagnosis and clinical management of CRC. METHODS: A total of 112 patients with CRC and 115 healthy control subjects were included in this study. Serum levels of matrix metalloproteinase (MMP)-7, MMP-9, MMP-11, tissue inhibitor of metalloproteinase (TIMP)-1, and TIMP-2 were analyzed by enzyme-linked immunosorbent assay, and carcinoembryonic antigen (CEA) and carbohydrate antigen (CA)19-9 levels were measured using an automatic immunoassay analyzer. RESULTS: MMP-7, MMP-9, MMP-11, TIMP-1, TIMP-2, CEA, and CA19-9 levels were all significantly higher in CRC patients compared with healthy controls. MMP-7, TIMP-1, and CEA levels were also closely related to clinicopathologic features in patients with CRC. The combination of serum CEA, MMP-7, and TIMP-1 significantly improved the diagnostic value compared with any single marker (area under the curve 0.858-0.890). Furthermore, a combined detection model including MMP-7, TIMP-1, and CEA improved both the specificity and sensitivity for detecting CRC. CONCLUSIONS: The results showed that combined detection of CEA, MMP-7, and TIMP-1 in serum could provide a specific and sensitive biomarker for the diagnosis of CRC.

Alu complementary DNA is enriched in atrophic macular degeneration and triggers retinal pigmented epithelium toxicity via cytosolic innate immunity.

Long interspersed nuclear element-1 (L1)­mediated reverse transcription (RT) of Alu RNA into cytoplasmic Alu complementary DNA (cDNA) has been implicated in retinal pigmented epithelium (RPE) degeneration. The mechanism of Alu cDNA­induced cytotoxicity and its relevance to human disease are unknown. Here we report that Alu cDNA is highly enriched in the RPE of human eyes with geographic atrophy, an untreatable form of age-related macular degeneration. We demonstrate that the DNA sensor cGAS engages Alu cDNA to induce cytosolic mitochondrial DNA escape, which amplifies cGAS activation, triggering RPE degeneration via the inflammasome. The L1-extinct rice rat was resistant to Alu RNA­induced Alu cDNA synthesis and RPE degeneration, which were enabled upon L1-RT overexpression. Nucleoside RT inhibitors (NRTIs), which inhibit both L1-RT and inflammasome activity, and NRTI derivatives (Kamuvudines) that inhibit inflammasome, but not RT, both block Alu cDNA toxicity, identifying inflammasome activation as the terminal effector of RPE degeneration.

Representation of Central Endothelial Cell Density by Analysis of Single Best Specular Microscopy Image Regardless of Cell Size Variance.

PURPOSE: The purpose of this study is to evaluate whether a single best image can represent central endothelial cell density (ECD) in corneas of differing cell size coefficient of variance (CV). METHODS: Four hundred one healthy eyes but with variant CV values were enrolled. For each eye, three nonoverlapping central cornea endothelium images were obtained with Konan NSP-9900 specular microscope. ECD and CV were evaluated by two independent graders using the well-established Center method. Only corneas with high image quality rating (IQR) and ECD >800 cell/mm2 by both graders were included in the study. The study sample was stratified into five CV levels (CV ≤ 35; ≥36; ≥38; ≥40; and ≥45). In each CV level, the ECD agreement, ECD variance, and the correlation between the ECD variation and CV values were analyzed. In addition, the ECD intragrader reproducibility and interframe differences were also analyzed for all levels except CV ≤ 35. RESULTS: The study sample includes a total of 278 eyes. High ECD agreement for the two independent graders (intraclass correlation coefficient [ICC] > 0.99), high ECD intragrader reproducibility (ICC > 0.95), low ECD variance (2.0% ± 1.6%, overall), no correlation between the ECD variation and the CV value (P > 0.05), and no significant ECD difference among frames (P > 0.05) was found in any studied CV levels. CONCLUSIONS: CV does not appear to be associated with ECD variance in the central cornea. TRANSLATIONAL RELEVANCE: This finding highlights that in healthy corneas but with high CV values, ECD can be reliably analyzed using one single image of best quality.

Reproducibility of Central Corneal Thickness Measurements in Normal Eyes Using the Zeiss Cirrus 5000 HD-OCT and Pentacam HR.

OBJECTIVES: To determine the repeatability and reproducibility of Central Corneal Thickness (CCT) measurements using two different anterior segment imaging modalities, including those obtained with the new anterior segment lens attachments for the Cirrus 5000 HD-OCT. METHODS: A total of 32 eyes from 16 normal volunteers (8 male, 8 female) were enrolled in this prospective study. CCT was measured by the same examiner using the Cirrus 5000 HD-OCT and Pentacam HR. The results of CCT obtained by each method were averaged and compared using t-test analysis. The agreement between the measurement methods was evaluated. Coefficient of Repeatability (CoR) and Intra-Class Correlation Coefficient (ICC) were computed. RESULTS: The mean measurements taken with the Cirrus OCT anterior chamber lens (CCTAC), HD cornea lens (CCTHDC) and pachymetry scans (CCTPach) were 545.35 ± 31.02, 537.87 ± 26.82, and 532.04 ± 29.82 µm, respectively. The mean CCT obtained with the Pentacam (CCTPent) was 545.51 ± 30.71 µm. CCTPent were significantly higher than CCTHDC and CCTPach (p< 0.0001). In contrast, the CCTPent and CCTAC were similar (p=0.87). CCT, as evaluated by the two different instruments, showed excellent correlation (r > 0.98, p< 0.0001) with an ICC > 0.99 (95% CI, 0.97 - 0.99). CoR was the highest for CCTPach (3.7 ± 1.4, 95% CI (3.0- 4.6)). CONCLUSION: CCT measurements from the Cirrus OCT using the new anterior segment lens attachments and the Pentacam HR are highly correlated. This should allow the use of a standardized correction factor if necessary to inter-relate the measurements between the two devices.