bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship between standard automated perimetry and high‐resolution optical coherence tomography in glaucoma patients
Authors: CALVO PEREZ P , FERRERAS A , ABADIA B , PABLO LE , PAJARIN AB , LARROSA JM
Published: September 2009

Purpose To determine the relationship between the main indices of standard automated perimetry (SAP) and the peripapillary retinal nerve fiber layer (RNFL) thickness measured with spectral‐domain optical coherence tomography (OCT) in patients with glaucomatous visual field defects.

Methods 47 consecutive patients with open‐angle glaucoma were included in the study. Only one eye per subject was randomly selected. SAPs were performed with a Humphrey perimeter and the 24‐2 SITA standard algorithm. All of them underwent imaging with the Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany). Left eye data were converted to a right eye format. The Kolmogorov Smirnov test was applied to check that the data were normally distributed. Pearson correlations were calculated between SAP indices (mean deviation, pattern standard deviation, and visual field index) and OCT parameters

Results The average visual field mean deviation was ‐6.50 dB. Mild to moderate correlations were observed between SAP indices and most OCT parameters. The strongest correlations were found between the inferior quadrant thickness and pattern standard deviation (‐0.544).

Conclusion The RNFL thicknesses measured with high‐resolution OCT showed moderate correlations with SAP indices in glaucoma patients. These results may help to understand the relationship between structural and functional changes in open‐angle glaucoma.
The retinal nerve fiber layer and the optic nerve head morphology after glaucoma surgery
Authors: GRACNER T , PAHOR D
Published: September 2009

Purpose To detect and quantify changes in the retinal nerve fiber layer (RNFL) and the optic nerve head (ONH) morphology after glaucoma surgery.

Methods 13 eyes of 13 patients with open‐angle glaucoma in which goniotrephining with scleral flap without intraoperative antimetabolites for progressive glaucoma damage was done were included in this prospective study. Before and 6 months after the surgery: the intraocular pressure (IOP) was measured, the thicknes of the RNFL was measured with a scanning laser polarimeter (GDx VCC), the confocal scanning laser ophthalmoscopy measurements of ONH with Heidelberg retina tomograph (HRT 3) were performed and the visual field was tested with Humphrey Field Analyser.

Results The mean IOP before surgery was 24.5 ? 2.3 mmHg decreasing 6 months after to a mean of 13.9 ? 3.0 mmHg (p<0.05). The RNFL measurements with GDx VCC revealed no differences between the mean TSNIT Avarage (p=0.383), mean Superior Avarage (p=0.756) and mean Inferior Avarage (p=0.269) before and after surgery. The ONH measurements with HRT 3 revealed postoperatively a significant increase in the mean Rim Area, Rim Volume and Cup Shape Measure, whereas Cup Area, Cup Volume and Linear Cup/Disc Ratio decreased (p<0.05). There were no differences between the mean Height Variation Contour (p=0.678) and Mean RNFL Thickness (p=0.064) before and after surgery. Preoperatively the mean value of the Mean Deviation on automated perimetry was –18.82 ? 8.5 dB improving 6 months postoperatively to a mean of –16.63 ? 7.9 dB (p<0.05).

Conclusion Our study demonstrated the beneficial effect of IOP reduction obtained with glaucoma surgery on visual field indices and ONH parameters evaluated by HRT 3.
Preterm and at term children: morphological and functional analysis of optic nerve and visual pathway with OCT, HRT and pVEP
Authors: ANGELI R , RUBERTO G , GUAGLIANO R , BERTONE C , BARILLA D , TRAVERSA E , SUZANI M , RUSTIONI G , PICCININI P , TINELLI C , VANDELLI G , MILANO G , BIANCHI PE
Published: September 2009

Purpose To compare optic nerve morphology and visual function in 14 preterm children(mean gestational age:33,38) with normal cerebral ultrasound at birth and 15 at term children (mean gestational age:39,67).

Methods Mean preterm age was 7,6 years, mean at term was 9,1 years. Children underwent to complete functional and morphological evaluation of Optic Nerve Head (ONH) with Heidelberg Retinal Tomography and Optical Coherence Tomography. The same children were evaluated at birth and at the time of morphological examinations by mean of transient and steady state pVEP.

Results Mean visual acuity was 9,85 in the preterm, 10 in the at term children. HRT in preterm and at term children at term(n=28) preterm(n=25) P value mean sd mean sd Disc Area 2,5 0,7 2,34 0,68 0,38 Cup Area 0,50 0,44 0,58 0,47 0,51 Rim Area 2 0,45 1,76 0,37 0,047 C/D Area Ratio 0,18 0,12 0,22 0,14 0,23 C/D Linear Ratio 0,4 0,15 0,45 0,16 0,30 Mean RNFL Thick 0,2 0,07 0,24 0,2 0,26 Tab.1 A statistically significant reduction was found in preterm children as regard rim area (p=0,047,tab 1) at HRT and superior RNFL thickness (p=0,01), temporal and inferior inner macular thickness (p=0,03) at OCT. Differences in the pVep latencies were found at 3 and 8 months after birth, but not at the time of morphological examination. Steady State pVEP amplitudes differences were not statistically significant.

Conclusion Morphologic optic disk and macula differences between term and preterm children seems not functionally affect the visual pathway.
Visual outcomes and safety of Intacs versus KeraRing intracorneal ring segment implantation in keratoconus
Authors: CANADAS SUAREZ P , HERNÁNDEZ‐VERDEJO J , MARINA C , TEUS‐GUEZALA M
Published: September 2009

Purpose To compare the safety and eficacy when two different types of intrastromal ring segments (ICRS): Intacs vs. KeraRing were used to treat keratoconus.

Methods Interventional, retrospective, comparative case serie study. A total of 53 keratoconic eyes were separated in two groups matched by age and degree of keratoconus: 31 (Group A) treated with Intacs ICRS and 22 (Group B) treated with KeraRing ICRS. Main outcomes were uncorrected, best corrected visual acuity (UVA and BCVA), sphere, astigmatism, spherical equivalent (EE) and mean keratometric values (km) pre and 3 month after implantation. Safety of the procedure was also evaluated. In both groups the femtosecond laser (IntraLase Corp, Irvine CA) were used to create the tunnel.

Results 3 month postop UVA were 0,26?0,2 vs 0,30?0,2 in Group A and B (p=0,6). BCVA was 0,61?0,2 and 0,67?0,2 in Group A and B (p=0,4). Postop sphere, cylinder and EE were ‐1,3?3,6D, 2,9?1,9D and ‐2,6?3,4D in Group A vs ‐1,3?1,8D, ‐3,1?2,0D and ‐2,2?2,4D in Group B respectively (p>0,05 in all comparison). Group A mean km was 43,1?12,6D vs 44,7?5.0D in Group B (p=0,6). Rate of explantation was 16,6% in Group A due to extrusion, neovascularization or non‐controled inflamation vs none in Group B.

Conclusion In this serie Intacs or KeraRing implantation to correct keratoconus seems to induce the same visual outcomes. However the tolerance of keraRing was better than intacs.
Comparision of deep anterior lamellar keratoplasty results in different TGFβI corneal dystrophies
Authors: NOWINSKA A , WYLEGALA E
Published: September 2009

Purpose To compare the results of deep anterior lamellar keratoplasty in eyes with TGFβI corneal dystrophies.

Methods 10 eyes of 8 patients with TGFβI corneal dystrophies after DALK were recruited for the study. There were 5 eyes with LCD1 (R124C), 2 eyes with atypical LCD (H626R), 2 eyes with TBCD (R555Q), and 1 eye with GCD1 (R555W). Main outcome measures were: complication noticed during Descemet membrane air dissection, 6 month graft and stromal bed clarity, presence of stromal bed folds during OCT exam, best corrected visual acuity (BCVA), corneal astigmatism and endothelial cell density (ECD).

Results Local Descemet membrane perforation during DALK occurred in 1 eye with R555W mutation and 2 eyes with H626R mutation. Descemet membrane detachment was diagnosed postoperatively in one eye with R124C mutation. DMD resolved spontaneously within one month. At 6 month all grafts reminded clear, but there were thick stromal bed folds visible during OCT exam in 1 eye with R555W mutation and 2 eyes with H626R mutation. BCVA was 0,8 in eyes with R555Q, 0,4 in eyes with R124C, 0,2 in eyes with H626R and 0,3 in eye with R555W mutation. There were no differences noticed in corneal astigmatism or ECD at 6 month. Mean corneal astigmatism was 3,3 D (± 0,43) and ECD was 2156 cells/mm2 (± 758).

Conclusion The TGFβI dystrophy type influences on the results after DALK. TBCD and LCD1 with no deep stromal or Descemet involvement are good candidates for DALK.
SITA‐SWAP and SITA‐SAP in glaucoma suspects
Authors: MILANO G , BOSSOLESI L , COLOMBO M , BORDIN M , LANTERI S , RAIMONDI M , ROSSI G
Published: September 2009

Purpose To compare the ability of Standard and Short‐Wavelength Automated Perimetry to point out early functional defects in glaucoma suspects picked up using imaging tests such as GDx‐VCC and HRT‐III

Methods Randomly selected 90 eyes of 90 patients screened on the basis of clinical suspicion of having early glaucoma, were submitted to a complete ophthalmic examination including GDx and HRT. Moorfields regression analysis(MRA), cup shape measure (CSM), rim area (RA) for HRT‐III and nerve fiber indicator (NFI), superior and inferior TSNIT average for GDx‐VCC were taken into account. If at least one of the parameters was found out of the normal limits, a 24‐2 SITA‐SAP and SITA‐SWAP tests. Mean defect (MD), pattern standard deviation (PSD), number of points significantly depressed <5% and <1% in the pattern deviation plot and test duration for SAP and SWAP were compared using the Wilcoxon signed rank test and Bland and Altman plot. Media opacities >1 according to LOCS‐III were excluded

Results According to the results of the Wilcoxon test SWAP gave a significantly larger MD and PSD defect than SAP (p<0.01) and a larger number of depressed points with p<1%(p<0.01). SWAP test duration was shorter than SAP(p<0.01). These results were not confirmed by Bland and Altman plot that could not point out significant differences between the parameters provided by SWAP and SAP

Conclusion In patients with suspicion of early glaucomatous damage given by imaging techniques (GDx‐VCC and HRT‐III), SITA‐SWAP is not able to identify a functional loss in all cases. The SITA applied to SWAP can improve the ability of the perimetric test to pick up early defects involving short‐wavelength sensitive ganglion cells at least in some patients and in a shorter test time than SITA‐SAP
Nitric oxide and cGMP protect the retina from ischemia and mediate somatostatin's neuroprotective effects
Authors: THERMOS K , KIAGIADAKI F , MASTRODIMOU N
Published: September 2009

Purpose The neuropeptide somatostatin has been shown to modulate retinal circuitry by activating its receptors (sst1‐sst5) found in retinal neurons and to influence the levels of other neuroactive substances such as nitric oxide (NO) and cGMP. In addition, it displays neuroprotective properties against retinal chemical ischemia and excitotoxicity. In another paradigm, somatostatin was shown to protect cortical cultures against NMDA induced neuronal death via a cGMP mechanism. These findings led us to investigate whether NO and/or cGMP could protect the retina from ischemia, and possibly underlie somatostatin’s neuroprotective actions.

Methods A model of chemical ischemia was employed in rat retina in order to examine the neuroprotective effects of arginine, the substrate of nitric oxide synthase (NOS), and a number of NO donors. Subsequently, blockade of NOS and guanylyl cyclase in the presence of somatostatin receptor (sst2) agonists was attempted to investigate the role of NO/cGMP in somatostatin’s protection of the retina in the chemical ischemia model and in a model of AMPA induced excitotoxicity.

Results The NO donors SIN‐1 and NONOate and 8‐Br‐cGMP protected the retina in a concentration‐dependent manner, as shown by ChAT immunoreactivity and TUNEL staining. L‐cysteine (the peroxynitrite scavenger) partially reduced the SIN‐1 protective effect. NOS and guanyl cyclase inhibitors reversed the protective effect of sst2 agonists in the chemical ischemia and excitotoxicity model.

Conclusion NO/peroxynitrite and cGMP appear to be important mediators in the protection of the retina from chemical ischemia. The NO/sGC/cGMP pathway is involved in the neuroprotective effects of the sst2 ligands in the same model and against AMPA excitotoxic insults.
Genetic influences on biomarkers in AMD
Authors: CHONG V
Published: September 2009

Purpose To describe the genetic influences on biomarkers in age‐related macular degeneration (AMD).

Methods We have previously demonstrated that AMD is associated with systemic activation of complement factors, alternation of cytokine levels, and changes in the matrix protein level. In this study, we examine the association of these changes with the genotype of the common "AMD" genes.

Results Activation of complement factors were closely associated with "at risk" complement factor polymorphisms. Plasma cytokine levels were not associated with complement factor H polymorphisms, but were associated with the "at risk" HTRA1 polymorphisms. Plasma matrix protein showed a trend association with the "at risk" HTRA1 polymorphisms.

Conclusion Traditional genotype‐phenotype correlation is based on clinical phenotype. Biomarker research is leading to a new area of genotype‐phenotype correlation research. It is unclear at this stage, how important these correlations are. Further studies are required.
Functional genomics of systemic complement activation in AMD
Authors: EDWARDS AO
Published: September 2009

Purpose To describe the current status of genetic variants associated with age‐related macular degeneration (AMD) and present functional genomic association studies demonstrating that systemic complement activation is inlfuenced by haplotypes in AMD risk loci and increases the risk of having age‐related macular degeneration.

Methods A genome wide association study using the Illumina 370 Beadchip on over 3000 subjects was performed. Focused genetic association and haplotype studies investigating the genetic mechanisms increasing AMD risk in complement and non‐complement AMD risk loci were performed using standard methods. Functional genomic association studies relating genetic risks for AMD to plasma complement levels measured using ELISA assays were performed.

Results The collaborative genome‐wide association study revealed novel pathways increasing the risk of AMD and will be discussed. The established genetic variants in the CFH, CFHR, FI, ARMS2 (10q26), and ApoE loci will be reviewed with a focus on insights from genetic studies on functional consequences. The proteogenomic association study showed that haplotypes in complement genes associated with AMD altered plasma levels of complement substrates, regulators, and activation by‐products. The majority of the difference between case and control levels of complement proteins in plasma was explained by the genetic variants associated with AMD.

Conclusion Multiple independent pathways leading to AMD have been identified using the genetic approach. Detailed genetic studies and functional genomic studies are beginning to suggest mechanisms through which AMD risk is increased.

Commercial interest
Recent developments of dry eye in children
Authors: BREMOND‐GIGNAC D
Published: September 2009

Purpose Dry eye syndrome in children is a rare disease sometimes difficult to diagnose. The research of the etiology can contribute to adjust the treatment.

Methods Two features of dry eye syndrome in children can be distinguished. Dry eye integrated in general disease with evidence of diagnosis and etiology and asymptomatic dry eye which needs a careful check up to recognize the primary etiology. Keratitis sicca usually does not lead to children complaint and simple signs as rubbing or blinking are often observed. Clinical and practical cases are described.

Results Review of literature confirms common conditions with adult dry eye but also the specificity of the pediatric dry eye. Dry eye in children is also commonly an inflammatory condition of the ocular surface. New treatment with their indications are listed including tear‐like topical therapies and anti‐inflammatory or immunosuppressive drugs for ocular surface with specificities in children.

Conclusion Dry eye syndrome in children must be recognized and diagnosed. In addition to classical tear‐like treatment, specific therapy should be adapted to the etiology.
Management of macular edema due to branch retinal vein occlusion with intravitreal injections of pegaptanib sodium
Authors: GALLEGO‐PINAZO R , DIAZ‐LLOPIS M , FRANCES‐MUNOZ E , UDAONDO‐MIRETE P , SALOM D , SANZ‐MARCO E , LOPEZ‐PRATS M , GARCIA‐DELPECH S
Published: September 2009

Purpose To evaluate the efficacy of Pegaptanib Sodium as single therapy for macular edema due to non‐ischemic branch retinal vein occlusion.

Methods In this uncontrolled prospective pilot study 17 patients have been included with non‐ischemic branch retinal vein occlusion. All of them showed macular edema in the OCT with central foveal thickness higher than 350 microns (mean, 541 +/‐ 140) and decrease in visual acuity lower than 0,5 Snellen ETDRS charts notation (mean, 0,16+/‐0,14). After an initial injection of Pegaptanib Sodium evaluations were programmed every 5 weeks and further retreatments were developed in cases with macular thickness higher than 300 microns. No other therapies were allowed at any point of the study.

Results During the follow‐up a mean number of 4,3 injections were needed to achieve a mean visual acuity of 0,35 +/‐ 0,28 and a mean macular thickness of 264 +/‐ 73 microns. All patients showed an improvement in both visual acuity and macular thickness. No systemic or ocular adverse event was registered.

Conclusion Intravitreal injections of Pegaptanib Sodium constitute a safe and effective new approach in the treatment of macular edema due to non‐ischemic branch retinal vein occlusion. Further controlled prospective trials are required to confirm our preliminary results.
VEGF is reduced in breast milk after intravitreal injection of bevacizumab
Authors: EHLKEN C , STAHL A , AGOSTINI HT
Published: September 2009

Purpose To measure the level of VEGF protein in serum and breast milk after intravitreal injection of bevacizumab and ranibizumab.

Methods Serum and breast milk samples before and after repeated intravitreal injections of bevacizumab and ranibizumab were collected from a 35‐year old female who was treated for CNV secondary to a chorioretinal scar and who was nursing her 4‐month old son. Samples were analysed for the level of VEGF protein via ELISA.

Results VEGF protein in the serum was reduced significantly to non‐detectable levels after intravitreal injection of bevacizumab and started to recover only after 6 weeks. After intravitreal injection of ranibizumab, however, only a temporary dip 3 days after injection could be detected. VEGF in breast milk was reduced by approximately one third directly after injection of bevacizumab. After injection of ranibizumab, the level of VEGF protein remained unaltered.

Conclusion Use of intravitreal VEGF inhibitors should be avoided during pregnancy or while nursing a baby. However, if necessary, ranibizumab seems to have a lower effect on VEGF in the serum or breast milk an should therefore be used.
Inflammatory factors in experimental retinal vein occlusion
Authors: REHAK M , HOLLBORN M , IANDIEV I , PANNICKE T , WIEDEMANN P , BRINGMANN A
Published: September 2009

Purpose Vascular endothelial growth factor (VEGF) is a key player in the development of macular edema (ME) in patients with retinal vein occlusion (RVO). In addition to VEGF, various other factors are altered in the hypoxic retina and influence the development of ME. In a rat model of RVO, we determined the changes in the gene expression of factors implicated in the development/resolution of ME (VEGF‐A, PEDF, IL‐6, Il‐1β, potassium und water channels) in the retina and pigment epithelium (RPE).

Methods In one eye of Long‐Evans rats (n=30), retinal veins near the optic nerve head were photocoagulated using a blue‐green argon laser. Untreated eyes served as controls. The eyes were enucleated 1, 3 and 7 days after laser treatment, and the mRNA levels were determined with real‐time PCR.

Results In the neural retina, VEFG expression showed fast upregulation at 1 day after RVO, and returned to the control level after 3 days. The expression of VEGF was not altered in the RPE. Potassium and water channels were downregulated in both tissues through the entire time period investigated. IL‐6 and IL‐1β were rapidly and strongly upregulated in the retina and RPE (to levels 80‐times higher as control) within 1 day after RVO, and decreased only slowly after 7 days.

Conclusion In RVO, there is fast and transient upregulation of the expression of VEGF, which is dominant for the acute stage of the disease. The strong and long‐lasting upregulation of IL‐6 and IL‐1β suggests that inflammatory factors play an important role in chronic hypoxia.
Microstructural alterations of the retinal arterial blood column along the vessel axis in healthy volunteers with age
Authors: LANZL IM , KHAROUBI A , SCHMIDT‐TRUCKSÄSS A , HALLE M , KOTLIAR KE
Published: September 2009

Purpose We demonstrated previously that roughness of the retinal arterial blood column measured along the vessel axis increases in anamnestically healthy volunteers with increasing age. We termed it longitudinal retinal arterial profile (LAP). Whether LAP is altered with age in medically supervised healthy persons is investigated.

Methods 82 medically healthy volunteers were examined by Dynamic Vessel Analyzer (IMEDOS, Jena, Germany) using stimulation with flickering light. 3 age groups were formed: young (N=27, 30,5±4,3 years), middle age (N=28, 42,3±3,3 years) and seniors (N=27, 64,0±5,0 years). Included in the analysis were volunteers without medical vascular risk factors defined as: blood pressure < 140/90 mmHg, HDL > 35 mg/dl, LDL < 190 mg/dl and glucose levels < 110 mg/dl. Retinal arterial diameters were measured along 1 mm vessel segments to obtain LAP. Differences were analyzed using Fourier transformation.

Results In all age groups LAP do not change during all stages of the arterial response. Arterial diameters in the senior group were reduced in comparison to the young group at all stages of the vessel reaction (p<0,05). There are differences in LAP between the age groups. Compared to young persons, seniors showed significantly diminished waves with a period of 417 µm at all stages of the arterial reaction, whereas young volunteers showed less pronounced waves with a period of 208 µm (p<0,05).

Conclusion Our results represent the healthy aging process in retinal vasculature. Age related microstructural changes in longitudinal profiles of retinal arteries in medically healthy persons might be an indication for alterations in the vascular endothelium and smooth musculature.
Adaptive optics applied to the vision simulator
Authors: CHATEAU N
Published: September 2009

Abstract not provided
The effect of upregulated LOX and LOXL2 on inflammation and fibrosis in a laser induced CNV model
Authors: VAN DE VEIRE S , VAN BERGEN T , VANDEWALLE E , MOONS L , SMITH V , OGG S , STALMANS I
Published: September 2009

Purpose Lysyl oxidase (LOX) and lysyl oxidase‐like protein 2 (LOXL2) are involved in the cross‐linking of collagen and elastin in the extracellular space. Therefore, these proteins play a major role in the process of fibrosis. This study was designed to elucidate the role of LOX and LOXL2 in inflammation and fibrosis after choroidal neovascularization (CNV).

Methods CNV was induced in 8 to 10 weeks old C75Bl/6 mice (n=5 per timepoint), by placing 3 laser spots at 9, 12 and 3 o’clock position (50µm, 0.1s and 400mW). Mice were sacrificed 2, 4, 7, 14, 28 and 35 days after lasering. LOX and LOXL2 expression in choroid and retina was analyzed using real time RT‐PCR. Inflammation and fibrosis was studied by different (immuno)stainings.

Results Both LOX and LOXL2 were significantly increased over time in the choroid and retina of lasered mice. LOX was 2.1, 3.2, 1.75, 1.3, 2 and 1.3 times upregulated on days 2, 4, 7, 14, 28 and 35 after laser, respectively, compared to non‐lasered eyes. LOXL2 was 1.1, 1.6, 1.3, 1.1, 1.5 and 1.2 times upregulated on day 2, 4, 7, 14, 28 and 35 after laser, respectively, versus non‐lasered eyes. On day 2 and 4 after the laser, the number of inflammatory cells was increased with 16% compared to control. A significant increase of collagen deposition was shown in the choroid on days 14, 28 and 35.

Conclusion A biphasic upregulation of LOX and LOXL2 was observed after CNV induction, which was associated with the inflammatory and fibrotic phase. Our data suggest that LOX and LOXL2 play a role in the process of inflammation and fibrosis after the induction of CNV. This finding can open new perspectives in the treatment of age‐related macular degeneration by inhibiting LOX and LOXL.
Intraocular pressure and associated factors in a Central Indian population. The Central India Eye and Medical Study
Authors: JONAS JB , NANGIA V , MATIN A , SINHA A , KULKARNI M , BHOJWANI K
Published: September 2009

Purpose To evaluate the intraocular pressure (IOP) and its associated factors in the adult population of rural India. .

Methods The Central India Eye and Medical Study is a population‐based study performed in a rural region close to Nagpur in Central India. It included 4711 subjects (aged 30+ years) out of 5885 eligible subjects (response rate: 80.1%). The participants underwent a detailed ophthalmic and medical examination. This study was focused on the IOP.

Results Out of the 4711 subjects (9422 eyes), IOP measurements were available for 9338 (99.1%) eyes of 4686 (99.5%) subjects. The mean IOP was 13.6±3.4 mm Hg (median: 14 mm Hg; range: 2–56 mm Hg). Assuming a Gaussian distribution curve, the normal range of IOP, defined as mean ± two standard deviations, was from 6.8 mm Hg to 20.4 mm Hg. In multivariate analysis, IOP was significantly associated with the systemic parameters of higher diastolic blood pressure (P<0.001), higher pulse rate (P=0.004), and higher body mass index (P=0.007); the socioeconomic parameters of higher level of education (P=0.004), higher cast (P=0.002), and no livestock ownership (P=0.01); and the ocular parameters of higher corneal refractive power (P<0.001), lower central corneal thickness (P=0.002) and higher myopic refractive error (P=0.002).

Conclusion The normal range of IOP was from 7 mm Hg to 20 mm Hg. Determinants of IOP were higher diastolic blood pressure, higher pulse rate, higher body mass index, higher level of education, higher cast, higher corneal refractive power, lower central corneal thickness and higher myopic refractive error.
Major eye diseases and risk factors associated with systemic hypertension in an adult chinese population: the Beijing Eye Study
Authors: LIBONDI T , JONAS JB , WANG S , XU L , WONG TY , CUI T , LI Y , YANG H , CONG S
Published: September 2009

Purpose To assess the relationship of hypertension with major eye diseases and other ocular parameters.

Methods The Beijing Eye Study is a population‐based study. Examination at baseline in 2001; follow‐up examination in 2006; 3222 subjects had blood pressure measurements.All participants underwent a thourough ophthalmic examination and blood pressure measurement. Hypertension was defined as a systolic blood pressure ≥140 mm Hg and/or a diastolic blood pressure ≥90 mm Hg, and/or self‐reported current treatment for hypertension with antihypertensive medication.

Results Mean age of participants in the present study was 60.4±10.0 years. Hypertension was present in 1500 (46.6%) of the 3222 subjects who had their blood pressure measured. In multiple regression analysis, hypertension was associated with higher intraocular pressure (P = 0.005), arterio‐venous nicking (P = 0.009),retinal vein occlusions (P = 0.02), and diabetic retinopathy (P = 0.02). Hypertension was not significantly associated with the prevalence of open‐angle glaucoma (P = 0.19) or angle‐closure glaucoma (P = 0.15), age‐related macular degeneration (P = 0.73), nuclear cataract (P = 0.88), posterior subcapsular cataract (P = 0.30), cortical cataract (P = 0.10), or area of alpha zone (P=0.05) or beta zone of parapapillary atrophy (P = 0.95).

Conclusion In Chinese persons, while controlling for other systemic parameters, hypertension was associated with increased intraocular pressure, retinal microvascular abnormalities, and prevalence of retinal vein occlusion and diabetic retinopathy. Hypertension was not associated significantly with age‐related macular degeneration, age‐related cataract, or glaucoma
Aging and glaucoma
Authors: PILLUNAT L
Published: September 2009

Purpose The rigidity of the eye increases with age. Sclera becomes stiffer and the compliance of lamina cribrosa (LC) is reduced. This is caused by modification (crosslinking) of collagens by advanced glycation endproducts (AGEs) or oxygen radicals due to oxidative stress and reduced antioxidants. Albon (2000) proved an increase of AGEs in LC with age.

Methods We showed the stiffening effect of AGEs on LC and peripapillary sclera in stress‐strain measurements. Additionally, these crosslinks cause an increase of collagen resistance against degradative enzymes which leads to an accumulation of collagen in the optic nerve head. Similar changes are observed also in glaucoma, but to a higher extent in comparison to age‐matched persons. The stiffness of sclera in glaucoma is higher (lower pressure buffer capacity).

Results Tezel (2006) found an incresased AGE‐content of 36% in the optic nerve head of glaucoma patients compared with 8% in age‐matched controls. Investigations show, that these biomechanical changes are clearly demonstrated after menopause. Therefore we concluded a hormonal prevention of these age‐related changes. These hormonal prevention is in glaucoma patients lower or not age‐related. Studies show an elevated concentration of follicle‐stimulating hormone (FSH), lutheotropic hormon (LH) and a by 50% reduced estradiol amount in glaucoma patients. Estrogen does not only possess an antioxidative effect like vitamin C or E. It influences the synthesis of collagen, proteoglycanes and MMPs. An adequate synthesis of glycosaminoglycanes makes the tissue more flexible. Estrogen stimulates also MMPs and reduces the stiffness of tissue.

Conclusion In glaucoma the oxidative and hormone status is not age‐related, which might be the cause of earlier vascular and biomechanical changes.
Sensitivity of applanation tonometry readings to the geometrical parameters of the sclera and the shape of the cornea
Authors: VORONKOVA E , BAUER S , TIPYASEV A
Published: September 2009

Purpose To study the effect of the geometrical parameters of a cornea (the thickness and difference of corneal shape from spherical segment) on applanation tonometry readings.

Methods The mathematical model for Goldmann and Maklakov tonometers is developed. The corneoscleral shell is modeled as two conjugated transversal isotropic elliptic (with non‐zero eccentricity) shells (cornea and sclera) with different mechanical properties. The baseline (prior to loading) two‐segment shell is assumed to be filled with incompressible liquid under pressure. Simulated IOP measurements are obtained for Goldman and 5‐g and 10‐g Maklakov tonometers. To analyze the effect of the eyeball geometry on IOP readings the elastic constants of cornea and sclera are varied and geometrical parameters (such as central corneal thickness, cornea and sclera radii of curvature, scleral thickness, ratio of anterior‐posterior eye axis lengths vs. the equator diameter) are varied. Simulated calculations are compared with experimental data.

Results The results are obtained over a wide range of parameters of the sclera and cornea.

Conclusion If the shape of a cornea differs from spherical it could cause the measurement error of tonometry IOP readings ranged between 3% and 25%. Significant sensitivity of the Goldmann tonometer to corneal thickness compared to Maklakov's method may be explained with smaller contact zone and, hence, the larger influence of the flexural (bending) deformation, which depends on the thickness of a shell. Contrariwise the change of the radius of curvature of cornea affects greatly on the results obtained with Maklakov tonometer.
Genetic and phenotypic analyses of retinitis pigmentosa in northern Tunisia
Authors: CHEBIL A , LARGUECHE L , CHOUCHENE I , BAKLOUTI K , MERDASSI A , ABDELHAK S , EL MATRI L
Published: September 2009

Purpose To describe the different types of retinitis pigmentosa (RP) in Northern Tunisia and to determine the genetic form.

Methods A prospective non‐comparative study was conducted. Different forms of RP disease were diagnosed in 99 patients from 56 families living in northern Tunisia. One hundred eighty individuals had ophthalmic examination including best corrected visual acuity, slit lamp biomicroscopy, fundus photography, and in some cases fluorescein angiography, OCT and electroretinogram (ERG). Clinical features, mode of presentation and mode of inheritance were noted. Blood samples were collected for genetic analyses. Gene RPE65 was screened in all affected cases.

Results Half of families presented first degree consanguinity. Sixty eight percent of cases were inherited by autosomal recessive transmission. Sporadic cases were estimated to 32%. Patients mean age at initial examination was 36 years (range: 2 to 70 years). Disease onset mean age was 15 years. Severe progression of disease with constriction of visual field, low vision and extended retinal atrophy was seen in 52% of patients. Among the 99 cases of RP, there were 80 commun forms, 9 Usher’s syndrome, 4 congenital amaurosis of Leber, 3 progressive cone‐rod degeneration, 1 paravenous form and 1 unilateral form. Mutation R19W of RPE65 gene was detected in two families.

Conclusion RP is a group of clinical and genetic heterogeneous diseases that can lead to blindness. RP in northern Tunisian population presents some particularities. The recessive severe form is largely predominant probably due to the elevated rate of consanguinity in Tunisia.
Urocortin2 relaxes the iris sphincter muscle
Authors: ROCHA DE SOUSA A , TAVARES‐SILVA M , FONSECA S , CARDOSO S , LEITE‐MOREIRA AF
Published: September 2009

Purpose Urocortin 2 (Ucn2) is an endogenous peptide of the corticotropin releasing factor family which presents many physiological effects at different levels in the organism. At the ocular level, Ucn2 is expressed in the retinal pigmented epithelium and has a protective effect in retinal degeneration pos‐ischemia. Also in the eye, Ucn2 has a vasodilator effect in the retinal circulation, specifically, in retinal resistance arterioles. This effect is diminished in diabetic mice. However, it has not been described yet the role of Ucn 2 in the neurohumoral regulation of the anterior segment of the eye. Our purpose is to characterize the effect of Ucn2 and its sub‐cellular pathways on iris sphincter muscle contraction.

Methods We tested the effect of increasing concentrations of Ucn2 (10‐10‐10‐6 M) on carbacol‐precontracted (10‐6 M) rabbit iris sphincter muscles (n = 9). The effect of Ucn2 was also tested in the presence of: (i) Nω‐nitro‐L‐Arginine (L‐NA; 10‐5 M; n = 13) and (ii) indomethacin (10‐5 M; n = 7).

Results Ucn2 promoted a concentration‐dependent decrease on active tension of the precontracted iris sphincter muscles, with maximal effect at 10‐6M (12,9 ± 4,1%). This effect was blunted with indomethacin (2,1 ± 4,4%) and with L‐NA(2,17 ± 5,79%) .

Conclusion Ucn2 promotes the relaxation of iris sphincter muscle. This effect is mediated by prostaglandins and it is also dependent on nitric oxide production. As observed Ucn2 is a new neurohumoral factor that modulates the relaxation of iris sphincter muscle.
Combined effects of aging and a pro‐diabetic diet on retinal function in a murine model of aging of the human eye
Authors: SIMON E , ACAR N , BRON AM , CREUZOT C , BRETILLON L
Published: September 2009

Purpose Improvement of life expectancy and changes in the dietary behaviour of developed populations are accompanied with the prevalence of diabetes and age‐related ocular pathologies. Aging of the retina is characterized by accumulation of lipids at its basement. Meanwhile increased oxidative stress is one of the features of aging and diabetes. The goal of our study was to evaluate the effects of a pro‐diabetic fructose‐rich diet on the functioning of the retina in a murine model of aging of the human eye, the ApoB100,LDLR‐/‐ mice.

Methods 4 month‐old ApoB100,LDLR‐/‐ and SF2J control mice were bred under either a standard chow or a fructose‐rich diet (60%) during 6 months (n=6 in each group). The functionality of the retina was further evaluated by single flash electroretinography (ERG) under scotopic conditions to assess the global response of the retina. Flicker ERG was monitored by increasing flash intensity upon 10Hz‐fixed frequency of the stimulus to specifically assess the sensitivity of rods and cones.

Results The fructose‐rich diet significantly decreased a‐ and b‐wave amplitudes of the retina to single flash ERG. This diminution was intensified in ApoB100, LDLR‐/‐ mice compared to control mice: ‐55.5% vs ‐33.4% for the a‐wave, ‐41% vs ‐38% for b‐wave, respectively. The fructose‐enriched diet impaired the sensitivity of rods by 0.3 log unit in both strains of mice.

Conclusion Oxidative stress triggered by a pro‐diabetic diet promotes the deleterious effects of aging on the retina by reducing its functionality and impairing its sensitivity to light stimulus.
Efficacy and safety of topical cyclosporine versus vehicle in vernal keratoconjunctivitis in children
Authors: BREMOND‐GIGNAC D , BERESNIAK A , CHIAMBARETTA F , AMRANE M , BAUDOUIN C
Published: September 2009

Purpose To evaluate safety and efficacy of topical cyclosporine with a cationic emulsion versus vehicle in vernal keratoconjunctivitis (VKC) in children.

Methods Vernal keratoconjunctivitis of 118 children (range 4 yo to 21 yo) diagnosed with giant papillae were randomized in 3 groups. During one month the first group was treated topically QID with cyclosporine 0,05%, or cyclosporine 0,1%, or with vehicle. For the next two months the treatment was similar except for the third group randomized to cyclosporine 0,05% or cyclosporine 0,1%. Patient subjective improvement (5‐points ordinal scale) was the primary criterion. Resampling simulations have been carried out to generate success rate distributions. Objective evaluation was a secondary criterion with corneal fluorescein staining appreciation.

Results The sex ratio of VKC was 1:4,4. Seasonal forms represented 23,7% of patients. The topical application of cyclosporine was rated comfortable by more than 76% of the patients at D28 and at 3 months. At D28, all groups showed subjective improvement; however when expressed in term of success/no success, subjective improvement was obtained for 89,8%, 84,6% and 70,0% of patients respectively with cyclosporine 0,05%, 0,1% and vehicle. Using resampling simulations, both success rates of 0.05% and 0.1% dosages were statistically significantly different (p<0.01) versus vehicle. Improvement (p<0.01) in overall rating of objective signs and corneal fluorescein staining was shown with cyclosporine 0,05%, 0,1% versus vehicle.

Conclusion Treatment by cyclosporine with cationic emulsion formulation appears well tolerated and efficient in children with VKC. New larger studies are necessary to confirm these first results.
Electronic subretinal implants allow blind retinitis pigmentosa patients to read letters and recognize the direction of fine stripe patterns
Authors: ZRENNER E , WILKE R , BARTZ‐SCHMIDT K , BENAV H , BESCH D , GEKELER F , KOCH J , PORUBSKA K , SACHS H , GREPPMAIER U , HARSCHER A , WILHELM B
Published: September 2009

Purpose Restoration of letter reading and stripe pattern recognition in blind RP patients by placing subretinal implants transchoroidally near the macula, consisting of two arrays: 4x4 electrodes controlled retroauricularly via a subdermal line for direct stimulation (“DS array”) and a "chip" (3x3x0,1 mm),1500 electrodes.

Methods Letters and stripe pattern were presented to 3 patients via the light sensitive chip – by patterns steadily presented at a screen. On the DS array the sensation evoked by each individual pulse consists of whitish round dot, clearly separated from its neighbor. Patterns consisting of such 4 x 4 dots correspond to letters of approximately 5 cm diameter presented at 60 cm distance.

Results Pat.1 correctly (20/24) recognized the direction of the letter “U”, presented with the opening in four different directions (DS array). Pat.2 correctly (12/12) differentiated letters via DS array (e.g. COIL). With the light sensitive chip, he correctly (22/24) differentiated letters (e.g. LITZ; 8,5 cm high, 1.7 cm line width) steadily presented on a screen at 62 cm distance Pat.3 recognized (15/20 correct, 4AFC) the direction of lines or stripe patterns with the chip, as did Pat.1 (11/14, 2AFC) and Pat.2 (11/12 4AFC) up to 0.35 cycles/deg.

Conclusion Active subretinal multielectrode implants with currents close to produce retinotopically correct patterns that allow for the first time recognition of individual letters and stripe patterns up to 0.35 cycles/deg clearly supporting the feasibility of light sensitive subretinal multi‐electrode devices for restoration of useful vision.
Acquired loss of chromatic sensitivity
Authors: BARBUR J
Published: September 2009

Purpose A range of ophthalmic and neurological conditions cause diminished visual performance, even when the subject is often unaware of any problems and the loss of vision remains undetected in conventional perimetry and visual acuity tests. The extent to which detection of acquired colour vision loss can revealed in subclinical cases and distinguished from congenital loss has been investigated.

Methods Over 400 subjects with congenital and acquired colour vision loss have been examined using conventional colour screening methods. In addition, the loss of yellow / blue and red / green chromatic sensitivity has been quantified using the CAD test (http://www.caa.co.uk/docs/33/200904.pdf). Those investigated included subjects with diseases of the retina and / or the optic nerve as well as patients with selective damage to central visual pathways. Patients with various stages of glaucoma, photoreceptor dystrophies, diabetes, optic neuritis, age‐related macular degeneration as well as tobacco and alcohol toxicity have been examined.

Results Algorithms developed for analysis of colour vision loss and automatic classification of congenital and / or acquired colour deficiency will be described. In acquired deficiency, the loss of chromatic sensitivity tends to affect both the rg and the yb channels. Significant differential effects have, however, been observed in relation to stimulus size, retinal location and state of light adaptation.

Conclusion The findings from these studies show that in the majority of these conditions, the loss of chromatic sensitivity is the most sensitive measure of early changes in diseases of the eye.
Pterygium surgery long term follow‐up
Authors: WOOD T , WILLIAMS E , WILLIAMS B
Published: September 2009

Purpose To determine if a pterygium surgical procedure consisting of minimal conjunctival removal, excision of the hypertrophic subconjunctival fibrovascular tissue, application of mitomycin 0.25 mg/ml for 1 minute combined with temporary nasal tarsorrhaphy, and postoperative dexamethasone/antibiotic drops achieved the following: safely simplified pterygium removal, controlled the early side effects of mitomycin, reduced the rate of recurrence, and eliminated the need for conjunctival transplantation.

Methods Twenty eyes of 19 patients underwent the procedure with mitomycin; fifteen were primary and 5, recurrent. These were compared to a previous group of 28 eyes in 26 patients that underwent pterygium/tarsorrhaphy surgery without mitomycin; twenty had primary and 8 had recurrent pterygia. Postoperatively, all eyes in both groups were treated with dexamethasone/antibiotic drops.

Results In the mitomycin group (average follow‐up 25 months), 19 of 20 eyes healed uneventfully. At 12 months, there had been no recurrences in the mitomycin group. In the non‐mitomycin group (average follow‐up 43 months), 9 (32%) recurred within 12 months; four (44%) of these required a second procedure at an average of 9 months. At 23 and 33 months, 2 (10%) eyes treated with mitomycin presented with asymptomatic, one mm recurrences that required no additional treatment. Conjunctival healing, as reflected in the time from surgery until tarsorrhaphy opening, was significantly longer in the mitomycin group, 37 vs. 17 days (P = .001).

Conclusion The described technique provided a safe and successful approach to pterygium management.
Alcohol vs. mechanical delamination in the treatment of corneal erosion: an electron microscopic study
Authors: PALADINI I , BRAHIMI B , MENCHINI U , DUA HS , ROMAGNOLI P , MENCUCCI R
Published: September 2009

Purpose To performed an electron microscopy study to investigate the cleavage plane and the efficacy of alcohol delamination in recurrent corneal erosion (RCE).

Methods By electron microscopy we analysed the epithelium of: seven controls treated with mechanical debridment, seven controls treated with alcohol delamination, ten cases of traumatic RCE and seven RCE due to MDFP treated with alcohol delamination, with special regard to the epithelial cells and the cleavage plane. Moreover we analysed four corneas from penetrating keratoplastys that were treated by alcohol delamination on the bench and both the epithelium and stroma were studied.

Results In traumatic RCE the basement membrane remained in situ, a precondition for quick epithelial healing . In MDFP the whole basement membrane was detached from the stroma and remained adherent to the epithelium, therefore after alcohol delamination the healing process should be different between MDFP and traumatic RCE.

Conclusion The present findings give strenght to alcohol delamination as a promising treatment for RCE
Lymphocyte and markers of inflammation detection in the conjunctival epithelium of patients with dry eye by enhanced flow cytometry
Authors: BARABINO S , MONTALDO E , SOLIGNANI F , MINGARI C , ROLANDO M
Published: September 2009

Purpose The aim of our study was to test the hypothesis that the use of cell culture medium can increase the number of cells obtained by impression cytology (IC) sampling of the conjunctiva in dry eye patients, and make the analysis of epithelial and lymphocyte cell populations with flow cytometry possible.

Methods IC specimens were collected in 15 normal subject and 15 dry eye patients. Samples collected from the right eye were placed in cell culture medium containing 10% foetal calf serum (FCS), and samples from the left eye in Phosphate Bufferred Saline containing 0.05% paraformaldehyde (PFA). The number of cells was analyzed by flow cytometry in both groups. Samples collected from a group of 30 dry eye patients were placed in FCS and stained for the expression of CK19, CD45, CD3, HLA‐DR, and analyzed by flow cytometry. A control group of 10 subjects was used as control.

Results The number of cells counted in the FCS samples was statistically increased in the normal (12791 ± 11350 events per minute) and dry eye group (23468 ± 15596) when compared to PFA samples (2031 ± 2336, and 2608 ± 1814 respectively). In dry eyes the low number of cells in PFA samples made possible only the analysis of HLA‐DR expression, while in FCS samples epithelial (CK19+), leukocyte (CD45+), and lymphocyte (CD3+) cell populations were characterized, other than analyzed for HLA‐DR expression.

Conclusion This study indicates that using this new method of preservation can enhance flow cytometry analysis of epithelial and immune cells of the conjunctiva in dry eye patients, opening new scenarios in the comprehension of its pathogenesis and in testing new therapies.