Thickness of anterior sclera and corneal layers in systemic sclerosis

PURPOSE

To evaluate the thickness of anterior sclera and corneal layers in patients with systemic sclerosis.

METHODS

The present cross-sectional study included 41 patients with systemic sclerosis and 41 age- and gender-matched healthy controls. The study and control groups were compared in terms of the thickness of anterior sclera, corneal epithelium, Bowman's layer, corneal stroma, and Descemet's membrane-endothelium complex. The thickness measurements were obtained using the anterior segment module of spectral-domain optical coherence tomography.

RESULTS

The thickness of anterior sclera, corneal epithelium, Bowman's layer, and Descemet's membrane-endothelium complex were similar in the patients with systemic sclerosis and healthy controls (P > 0.05). Total corneal thickness at the apex was 511.1 ± 33.5 µm in the systemic sclerosis group and 528.4 ± 29.5 µm in the control group (P = 0.015). The corneal stroma was thinner in the systemic sclerosis patients compared to the healthy controls (P = 0.02).

CONCLUSIONS

The corneal stroma was thinner in the patients with systemic sclerosis compared to that of healthy controls, while the thickness of the anterior sclera was similar in both groups.

Iris thickness measurements in patients with diabetic retinopathy

Purpose:

The aim of the study was to investigate iris alterations in diabetic retinopathy (DR).

Methods:

Sixty-nine eyes of 69 patients were recruited and three groups of patients were examined: proliferative DR ( n = 25), non-proliferative DR ( n = 21) and healthy controls ( n = 23). Macular optical coherence tomography (OCT), anterior segment iris OCT, and slit lamp digital camera photographs were taken. The thicknesses of the iris at a distance of 1 mm, 2 mm, and 3 mm from pupil margin were measured via iris OCT. Iris crypt count, furrow extent, color tone and collarette/diameter ratio were measured by means of anterior segment photography. Visual acuity, refractive error, intraocular pressure, and numbers of intravitreal injections were also recorded.

Results:

The iris thickness measurements at 1 mm from pupil margin were significantly correlated with the macular thickness measurements ( r = 0.32, p = 0.016). In the proliferative DR group, total number of injections were significantly correlated with the iris thickness measurements at 1 mm ( r = 0.25, p = 0.04). The iris thickness measurements at distances 1 mm, 2 mm, and 3 mm from the pupil margin were similar in all of the groups ( p > 0.05). Iris thickness did not correlate with age, intra-ocular pressure and collarette iris ratio in all the participants ( p > 0.05).

Conclusion:

Iris thickness is similar in diabetic patients and healthy controls. Meanwhile, iris thickness near the pupillary margin is positively correlated with macular thickness.

Inner retinal thickness and optic disc measurements in obese children and adolescents

PURPOSE

This study aimed to evaluate optic nerve head parameters and inner retinal layer thicknesses in obese children and adolescents.

METHODS

Forty-one eyes of 41 pediatric obese participants and 41 eyes of 41 age- and sex-matched healthy controls were included in this study. Body mass index was calculated, based on sex and age, using body weight and height measurements. Blood lipid values (i.e., cholesterol, low-density lipoprotein, high-density lipoprotein, and triglyceride) were measured in obese participants. Optical coherence tomography was used to examine optic nerve head parameters, including rim area, disc area, cup-to-disc ratio, and cup volume, as well as the thicknesses of retinal nerve fiber layers and macular ganglion cell-inner plexiform layers.

RESULTS

Optic disc parameters were similar in obese and healthy children (p>0.05). The percentage of binocular retinal nerve fiber layer thickness symmetry was significantly different between obese and control groups (p=0.003). Compared to the control group, participants in the obese group exhibited thinner retinal nerve fiber layers in the superior quadrants (p=0.04) and thinner ganglion cell-inner plexiform layers in the superior-temporal sectors (p=0.04). There were no statistically significant correlations between the ocular parameters and lipid blood test values assessed in this study (p>0.05). Body mass index was significantly negatively correlated with the mean retinal nerve fiber layer thickness (r=-0.33, p=0.03) in the obese group. There was no significant correlation between intraocular pressure and body mass index (r=0.05, p=0.74).

CONCLUSION

Compared to healthy children, obese children had greater binocular retinal nerve fiber layer thickness asymmetry and thinner retinal nerve fiber and ganglion cell-inner plexiform layers in several sectors. Blood lipid levels were not associated with retinal thickness or optic disc parameters in obese children.

Evaluation of corneal layers and anterior sclera in patients with primary Sjögren's syndrome

PURPOSE

We aimed to compare the thickness of anterior sclera, corneal layers, and pre-ocular tear film between patients with primary Sjögren's syndrome and healthy individuals.

METHODS

Fifty-one patients with primary Sjögren's syndrome and 41 healthy control participants were recruited in this cross-sectional and comparative study. The thickness of the pre-ocular tear film, corneal epithelium, Bowman's layer, stroma, Descemet's membrane, and endothelium were measured on the corneal apex. Anterior scleral thickness was measured at distances of 1 mm and 3 mm from the limbus. The anterior segment module of spectral-domain optical coherence tomography was used to measure thicknesses of pre-ocular tear film, corneal layers, and anterior sclera.

RESULTS

Tear film thickness, Schirmer's test, and tear break up time values were significantly lower in the Sjögren's disease group than in the healthy controls (p<0.05). The thickness measurements of corneal layers and sclera were similar between the groups. Tear film thickness was moderately correlated with the Schirmer's test results (r=0.34, p=0.001), but there was no correlation between the Schirmer's test results and tear break up time (r=0.18, p=0.09).

CONCLUSIONS

Pre-ocular tear film, as measured by anterior segment optical coherence tomography, was thinner in patients with primary Sjögren's syndrome than in the healthy controls. The thicknesses of corneal layers and anterior sclera were similar between the groups.

Evaluation of optic disc, retinal nerve fiber and macular ganglion cell layers in pediatric diabetes

PURPOSE

Our aim was to compare optic disc parameters, retinal nerve fiber (RNFL) and macular ganglion cell layers between children and adolescents with diabetes mellitus (type 1) and healthy controls.

METHODS

Sixty-three eyes of 63 pediatric diabetic patients without diabetic retinopathy and 44 eyes of 44 healthy controls were included in this cross-sectional and comparative study. Diabetic and control groups were similar in the aspect of age, gender and refractive error. Measurements of optic disc parameters (i.e., rim area, disc area, cup-to-disc ratio, cup volume), thickness of RNFL and macular ganglion cell-inner plexiform layers (GCL + IPL) were taken with the spectral domain optical coherence tomography.

RESULTS

There were not statistically significant differences between the diabetic patients and healthy controls in terms of intraocular pressure (p = 0.14), retinal nerve fiber layer thickness (p = 0.61), rim area (p = 0.92), disc area (p = 0.10), vertical cup-to-disc ratio (p = 0.16), cup volume (p = 0.13), and average macular GCL + IPL thickness (p = 0.43). On the other hand, binocular RNFL thickness symmetry percentage was statistically significantly different in the diabetic and control groups (p = 0.01).

CONCLUSION

Diabetic children and adolescents without diabetic retinopathy have more binocular RNFL thickness asymmetry compared to healthy controls.

Assessment of optic disc and ganglion cell layer in diabetes mellitus type 2

The purpose of this study was to compare the optic disc parameters, retinal nerve fiber (RNFL), and macular ganglion cell layers between patients with diabetes mellitus (DM) type 2 and healthy controls.In this cross-sectional study, 69 eyes of 69 diabetic patients without diabetic retinopathy and 47 eyes of 47 healthy controls were included. Optic disc parameters (i.e., rim area, disc area, cup to disc ratio, cup volume), RNFL, and macular ganglion cell-inner plexiform layers (GCL + IPL) thickness were measured by means of spectral domain optical coherence tomography.There were not statistically significant differences between the diabetic patients and healthy controls in terms of RNFL thickness (P = .32), rim area (P = .20), disc area (P = .16), cup volume (P = .12), and average macular GCL + IPL thickness (P = .11). Nevertheless, binocular RNFL thickness symmetry percentage (P =.03), average cup to disc ratio (P = .02), and superior-nasal macular GCL + IPL thickness (P = .04) were statistically significantly different in the diabetic and control groups.Diabetic patients without retinopathy have more binocular RNFL thickness asymmetry, higher cup to disc ratio, and thinner sectoral macular GCL + IPL when compared to healthy controls. Our results may support the statement that DM causes inner retinal neurodegenerative changes.

Publication trends in corneal transplantation: a bibliometric analysis

Background

Our aim was to demonstrate the publication trends of corneal transplantation in the last decade.

Methods

All of the keratoplasty research articles, letters, case reports, reviews and meeting abstracts published between January 2006 and December 2015 indexed on the Thomson Reuters Web of Knowledge were evaluated. A bibliometric filter was used to capture keratoplasty related publications by using the key words ‘keratoplasty’, ‘corneal transplantation’ or ‘keratoprosthesis’ in the ‘title’ selection mode.

Results

A total of 2726 publications were evaluated in the present study. Documents related to penetrating keratoplasty only have been decreased, whereas the documents related to endothelial keratoplasty were increased in the last decade. The total keratoplasty publication counts had been increased from the year 2006 to 2015. The average citation count per keratoplasty documents was 9.34.

Conclusions

There is a growing interest to the lamellar keratoplasty techniques especially the endothelial keratoplasty in the last decade.

Measurements of anterior segment parameters using three different non-contact optical devices in keratoconus patients

AIM

To evaluate the measurements of anterior segment parameters using three different non-contact optical devices in keratoconus patients.

METHODS

A hundred and one eyes of 55 keratoconus patients were enrolled in this study. The mean age was 26.2±8.9 years. The inclusion criteria were keratoconus stage I to III according to the Amsler-Krumeich keratoconus classification. All the measurements were done by the same operator, under the mesopic light condition and repeated with three different optical methods; Visante, Orbscan and Pentacam. The evaluated anterior segment parameters were anterior chamber depth (ACD), central and thinnest corneal thickness (CCT and TCT) and pupil diameter (PD).

RESULTS

THE MEAN CCT MEASURED BY VISANTE, ORBSCAN AND PENTACAM WERE AS FOLLOWS: 462.0±48.1µm, 463.9±60.9µm, 476.5±45.3µm, respectively (P=0.873). The mean ACD values were 3.34±0.33mm, 3.26±0.33mm, 3.49±0.40mm, respectively (P=0.118). The mean PD measurements were 5.11±1.14mm, 4.80±0.85mm, 3.80±1.38mm, respectively (P<0.001). The mean TCT measurements of Visante, Orbscan and Pentacam were 437.9±48.2µm, 447.6±60.6µm and 459.9±44.0µm, respectively (P=0.214). The Visante and Orbscan measured CCT similarly, while Pentacam measured CCT thicker than the other two. The Visante measured TCT thinner than the other two devices. In ACD measurements, Orbscan was the one giving the lowest values. PD was measured differently by the devices.

CONCLUSION

Although TCT, CCT and ACD measurements acquired by Visante, Orbscan and Pentacam in keratoconus patients are similar, PD measurements show large differences among the devices.

The effects of posterior continuous curvilinear capsulorhexis on contrast sensitivity

PURPOSE

We aimed at evaluating the effects of posterior continuous curvilinear capsulorhexis (PCCC) on contrast sensitivity.

MATERIALS AND METHODS

In this prospective, randomized, bilateral clinical study, 40 eyes of 20 patients who underwent bilateral cataract surgery were included. The phacoemulsification machine, viscoelastic substances, surgical tools, and intraocular lenses (IOLs) were the same for both eyes. The only difference was that we conducted the PCCC procedure before IOL implantation to one of the eyes of the patients. The selection of the eye that underwent the PCCC procedure was decided randomly.

RESULTS

The mean photopic contrast sensitivity values at spatial frequencies of 1.5, 3, 6, 12, and 18 cpd (cycles per degree) were 41.55, 59.90, 61.25, 32.35, and 9.75, respectively, and for the control group these values were 39.05, 56.60, 57.95, 29.80, and 8.75, respectively. The mean mesopic contrast sensitivity values at special frequencies of 1.5, 3, 6, 12, and 18 cpd were 41.20, 54.75, 55.55, 31.70, and 9.00, respectively, and for the control group these values were 38.35, 51.70, 52.15, 30.05, and 8.00, respectively. The mean contrast sensitivity values of the eyes that underwent the PCCC procedure were slightly better than the fellow eyes at all spatial frequencies, but the difference was statistically insignificant (P>0.05).

CONCLUSIONS

In early post-operative period, the PCCC procedure exerts some positive effects on contrast sensitivity although these effects are statistically insignificant.

Chorionic gonadotrophin beta subunit mRNA but not luteinising hormone beta subunit mRNA is expressed in the pituitary of the common marmoset (Callithrix jacchus)

The pituitary gonadotrophins LH and FSH are responsible for regulation of gametogenesis in the testis and ovary. Chorionic gonadotrophin (CG), a third closely related glycoprotein hormone derived by gene duplication of the LHbeta gene and secreted by the placenta in primates, is essential for the rescue of the corpus luteum and maintenance of pregnancy. We have recently shown that marmoset (m) CGbeta mRNA is highly expressed in the pituitary of the common marmoset (Callithrix jacchus) and that LH is less active than human CG in activating the human LH receptor lacking exon 10. To investigate further which gonadotrophin is the actual ligand of the LH receptor (LHR) of the marmoset monkey that naturally lacks exon 10, we identified and characterised the genomic organisation of the mLHbeta gene and its expression. Intergenic PCR amplification of the region encompassing the mLHbeta and the mCGbeta genes revealed that, surprisingly, mCGbeta is located 20 kbp upstream of the LHbeta gene, whereas in other species the intergenic distance is approximately 2-3 kbp. Sequence analysis of the mLHbeta coding region showed 70% identity to mCGbeta and 90% identity to human LHbeta at the amino acid level. Both gonadotrophin beta subunits are present at the genomic level, but RT-PCR of pituitary and placental total RNA using specific oligonucleotides for mCGbeta and mLHbeta showed high expression of mCGbeta mRNA in both tissues, whereas LHbeta was expressed neither in the pituitary nor in the placenta. Thus mLHbeta mRNA is lacking in the marmoset pituitary. Immunohistochemistry of marmoset pituitaries showed that mCG was confined to the gonadotrophes, and partly co-localised in cells stained positively for FSH. Western blot analysis confirmed the presence of mCG in the pituitary. Northern blot analysis using mCGbeta as a probe displayed one transcript of 0.7 kb in the pituitary and detected two transcripts of 1.1 kb and 2 kb in the marmoset placenta. Our results suggest that, in the common marmoset, CG is the only gonadotrophin with luteinising function that is present in the pituitary. We postulate that, owing to an unknown mutational event in evolution, expression of mLH was completely abolished, and CG - which, unlike LH, acts normally even when exon 10 is missing from the LHR - took over its function.

The structure and organization of the human follicle-stimulating hormone receptor (FSHR) gene

The structure and organization of the human follicle-stimulating hormone receptor (FSHR) gene were determined by either screening a phage library of human genomic DNA or applying the long PCR technique to amplify different exon pairs with their corresponding introns. The FSHR gene spans a region of 54 kb and consists of 10 exons and 9 introns. Most of the extracellular domain is encoded by 9 exons, ranging in length between 69 and 251 bp; the C-terminal part of the extracellular domain, the transmembrane domain, and the intracellular domain are encoded by the large exon 10 (1234 bp). Overall the gene encodes 695 amino acids. The structure of the human FSHR displays striking similarity to that of the previously characterized rat FSHR gene, with a high degree of conservation in exon sizes and exon/intron junctions.

Altered transferrin gene expression in preneoplastic and neoplastic liver lesions induced in rats with N-nitrosomorpholine

The expression of the gene for the iron transport protein transferrin was found to be altered in preneoplastic and neoplastic lesions induced in the rat liver by N-nitrosomorpholine. The total RNA of ten hepatocellular carcinomas (HCC) was investigated by Northern blot analysis using a cDNA-probe comprising 150 bp of the 3' region and compared with the total hepatic RNA in untreated rats. Seven hepatocellular carcinomas showed slight or pronounced reduction in transferrin expression. In situ hybridization of two additional hepatocellular carcinomas revealed marked reduction in the mRNA level for the transferrin gene compared with the surrounding tissue. In contrast, the majority of early preneoplastic lesions storing excess glycogen and tigroid cell foci expressed increased levels of transferrin mRNA. The loss of glycogen in mixed cell foci, which represent a later stage of hepatocarcinogenesis, was usually accompanied by a decrease in transferrin mRNA suggesting a close relationship between this change in gene expression and cellular dedifferentiation emerging during hepatocarcinogenesis.

The nucleotide sequence of rat liver glycogen phosphorylase cDNA

The nucleotide sequence of a cDNA coding for rat liver glycogen phosphorylase has been determined. The 2715 base pairs of the cDNA are sufficient to encode the total protein as determined by comparison with the liver type of glycogen phosphorylase of man. Human and rat liver glycogen phosphorylase showed 86% homology at the DNA level whereas the deduced amino acid sequence has 93.5% identity.