bluuebunny/crossref_metadata_2025_split huggingface dataset:
Choroidal blood flow response to hyperoxia and hypercapnia in patients with obstructive sleep apnea syndrome
Authors: KHAYI H , TONINI M , PEPIN JL , RENARD E , BAGUET JP , ROMANET JP , GEISER MH , CHIQUET C 
Published: September 2009

Abstract Purpose Obstructive sleep apnea syndrome (OSA) is associated with ischemic and glaucomatous optic neuropathy. The physiopathology of these diseases includes an abnormal regulation in the optic nerve head vasculature. The aim of our study was to characterize the choroidal vascular reactivity to hyperoxia and 8% CO2 breathing in OSA patients, as compared with matched healthy control subjects. Methods Eighteen newly diagnosed OSA patients were included in this prospective study. Control subjects were matched with OSA patients for body mass index (BMI), gender and age. At the screening visit, each subject underwent a general exam, cardiovascular, neurologic and ophthalmological examinations, and underwent complete overnight polysomnography. The LDF instrument used in this study to measure subfoveal choroidal blood flow (ChBF) measured the following parameters: ChBVel (kHz); volume, ChBVol (in arbitrary units, AU) and the relative flow, ChBF = ChBVel ? ChBVol (in AU). Vascular choroidal reactivity was tested during hyperoxia and hypercapnia (8% CO2) inhalation. Results OSA patients exhibited a similar choroidal reactivity during hyperoxia (stability of choroidal blood flow) and hypercapnia (1.5% increase in choroidal blood flow per 1 mmHg PtCO2) than controls. Conclusion This prospective comparative study explored for the first time the choroidal blood flow of OSA patients and results showed that subfoveal ChBF reactivity to gas in OSA patients is similar to healthy control subjects. These preliminary results suggest that choroidal vasculature is protected against the inbalance between the vasodilation (NO) and vasoconstriction (endothelin) system.
Retrobulbar flow velocities in open angle glaucoma and their association with mean arterial blood pressure
Authors: KAYA S , FUCHSJAEGER‐MAYRL G , RESCH H , GARHOFER G , PEMP B , VASS C , SCHMETTERER L 
Published: September 2009

Abstract Purpose Previous experiments indicate that vascular dysregulation may play an important role in the pathogenesis of primary open angle glaucoma (POAG). Furthermore, evidence has been provided that reduced flow velocities as assessed with color Doppler imaging (CDI) are a risk factor for the progression of the disease. In the present study the association between retrobulbar flow velocities as measured with color Doppler imaging and ocular perfusion pressure were compared in patients with POAG and healthy control subjects. Methods 253 patients with POAG and 198 healthy subjects have been included in this study. Peak systolic (PSV), end diastolic (EDV) and mean blood flow velocity (MFV) in the ophthalmic artery, the central retinal artery and posterior ciliary arteries was assessed using Doppler ultrasound. Resistance Index was then calculated as (PSV‐EDV)/PSV. Ocular perfusion pressure (OPP) was assessed based on measurements of systemic blood pressure and intraocular pressure. Results Intraocular pressure was higher in glaucoma patients than in healthy controls (p < 0.01). All flow velocities were significantly reduced in POAG patients as compared to healthy control subjects (p < 0.01 each), whereas resistance index was increased in POAG. An association between blood velocities was found between OPP and blood velocities in both groups. This association was, however, higher in POAG patients than in the healthy control group. Conclusion The present study indicates that there is a more pronounced association between retrobulbar flow velocities and OPP in POAG patients than in healthy control subjects. This supports the hypothesis that vascular dysregulation is present in patients with POAG.
Cis‐urocanic acid suppresses UV‐B‐induced interleukin‐6 secretion and cytotoxicity in human corneal and conjunctival epithelial cells in vitro
Authors: VIIRI J , JAUHONEN HM , RYHäNEN T , PAIMELA T , SORRI I , LAIHIA JK , LEINO L , SALMINEN A , KAARNIRANTA K 
Published: September 2009

Abstract Purpose Urocanic acid (UCA) is a major UV‐absorbing endogenous chromophore in the epidermis and is also an efficacious immunosuppressant. The anti‐inflammatory and cytoprotective effects of cis‐UCA were studied in ocular surface cell cultures exposed to UV‐B irradiation. Methods Human corneal epithelial cells (HCE‐2) and human conjunctival epithelial cells (HCEC) were incubated with 10, 100, 1000, and 5000 µg/ml cis‐UCA with and without a single UV‐B irradiation dose. Cell viability was measured by the colorimetric MTT (3‐(4,5‐dimethyldiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) assay. Results The UV‐B irradiation elevated IL‐6 secretion by 7 to 9‐fold in HCE‐2 cells and by 2‐fold in HCEC cells as analyzed with ELISA., declined by 30 to 50 % in HCE‐2 cells and by 20 to 40 % in HCEC cells after UVB irradiation. Treatment with 100 µg/ml cis‐UCA completely prevented both the elevated IL‐6 secretion and the decrease in cell viability to the same level as nonirradiated control cells in both cell types, i.e. simultaneous anti‐inflammatory and cytoprotective effects against UV‐B radiation.No significant effects on IL‐6 secretion or viability of the nonirradiated cells were observed with 10 and 100 µg/ml cis‐UCA, while 1000 µg/ml cis‐UCA evoked secretion of IL‐6 in both cell types. The 5000 µg/ml concentration was toxic. Conclusion Cis‐UCA may represent a promising anti‐inflammatory and cytoprotective treatment option to suppress UV‐B‐induced inflammation and cellular damage in human corneal and conjunctival epithelial cells.
Investigation of particular surgical steps in epiretinal prostheses implantation procedure in pigs
Authors: IVASTINOVIC D , GEORGI T , HORNIG R , WEDRICH A , VELIKAY‐PAREL M 
Published: September 2009

Abstract Purpose Proliferative vitreoretinopathy (PVR) is known a known complication of implantation of epiretinal prostheses in porcine eyes using our combined surgical procedure of vitrectomy, lensectomy, large scleral incision and retinal tack insertion. The aim of the present experimental study is to investigate the intraocular reaction to particular parts of the epiretinal prostheses implantation procedure in pigs. Methods 15 pigs were divided into 3 groups. Group 1 (n=6) underwent vitrectomy, lensectomy, insertion of inactive epiretinal prosthesis through a scleral incision and fixation to the posterior pole with a retinal tack. In group 2 (n=5) vitrectomy, scleral incision and retinal tack insertion were performed. Group 3 (n=4) received vitrectomy, scleral incision and insertion of a shortened prosthesis into the vitreous cavity. The follow up was 4 weeks. Results PVR was observed in all eyes of group 1 and in one eye of the group 3 with unintentional perforation of the lens capsule by the shortened implant. In all other eyes funduscopy revealed no clinical pathology. Conclusion Our results indicate that lensectomy is the key stimulus for PVR in porcine eyes while other steps of the implantation procedure are well tolerated. Though pigs do not seem to be a reactive animal model, lens manipulation should be avoided in the surgical procedure for the implantation of retinal prostheses.
Sutureless encircling band – biomechanical calculations and clinical experience
Authors: MAIER M , FEUCHT N , WINKLER VON MOHRENFELS C , KOTLIAR KE , LOHMANN CP 
Published: September 2009

Abstract Purpose In cases with multiple retinal breaks and in combination with vitrectomy in eyes with Proliferative vitreoretinopathy (PVR) for retinal detachment surgery often an encircling band is used. Usually the encircling band is fixed with non absorbable sutures. Methods A fixation method for an encircling band in retinal detachment surgery with one scleral tunnel in every of the 4 quadrants is reported. We describe our experience and biomechanical calculations of this fixation technique. Results In comparison to conventional fixation technique we found the following advantages: No suture is necessary, this means no additional foreign body can produce irritations. The scleral tunnel is safe and the preparation under the microscope can be performed fast and well controlled. Sclera tunnel fixation is very comfortable in combination with a vitrectomy. Conclusion With a short learning curve the operating time is as short as with conventional suture fixation of the encircling band. There is less perforating risc, less irritation and less patient discomfort postoperatively. A sutureless encircling band with sclera tunnel fixation is a very usefull operation technique in clinical routine.
The study of chromatic and achromatic VEP in the first year of life
Authors: TEKAVCIC POMPE M , STIRN KRANJC B , BRECELJ J 
Published: September 2009

Abstract Purpose To study chromatic and achromatic VEP responses in the first year of life. Methods In 30 babies aged 2 to 12 months VEP to chromatic and achromatic stimuli were binocularly recorded. Chromatic VEP were recorded to isoluminant red‐green and blue‐yellow stimulus. The stimulus was a circle composed of horizontal sinusoidal gratings with 90 % chromatic contrast. Two stimulus sizes (7 deg and 21 deg) were used. The stimulus was presented in an onset‐offset mode (on – 300ms, off – 700 ms). Achromatic VEP were recorded to black and white checkerboard (50′ square size), which was presented in pattern reversal (reversal VEP) and onset‐offset (onset VEP) mode. VEP were recorded from Oz (mid occipital) position and the reference was at Fz. Results Chromatic VEP responses were present in all babies, except youngest two (2 months old). The positive wave (P) amplitude to red‐green and blue‐yellow stimulus increased with age when using both stimulus sizes. Achromatic VEP responses were present in all babies. P100 wave (pattern reversal stimulation) showed longer latency in youngest babies (p=0.045), whereas its amplitude did not change throughout the first year of life. C1 wave (onset‐offset stimulation) showed longer latency in youngest babies (p=0.0039), whereas its amplitude decreased with increasing age (p=0.0087). Conclusion Chromatic VEP responses can be recorded in babies after the age of 3 months and show marked maturational changes throughout the first year of life.
Chromatic sensitivity in subjects with diabetes
Authors: O'NEILL‐BIBA M , RODRIGUEZ‐CARMONA M , RAUSCHER F , BARBUR J , SIVAPRASAD S 
Published: September 2009

Abstract Purpose Diabetic retinopathy is a major cause of blindness in the Western World and remains one of the most serious complications of diabetes mellitus. The gold standard to measure functional change in diabetic (DB) patients is LogMAR or Snellen VA. The aim of this study was to measure and characterise the severity of visual function loss in subjects with DB using sensitive psychophysical tests and to quantify accurately how changes in management of the disease correlate with changes in visual function. Methods Three groups of patients (n=50) were included in this study:DB patients with and without retinopathy and patients with no DB. Each patient had a full ophthalmic examination prior to psychophysical assessment. Colour vision assessment was carried out using the CAD test (Colour Assessment & Diagnosis) that provides a measure of both yellow‐blue and red‐green loss of chromatic sensitivity (CS). Rapid flicker (RF) was also measured by assessing sensitivity to a 20Hz flicker stimulus at five locations in the central visual field (fovea and 1.5 degrees from fixation in each quadrant). All tests were carried out at photopic and high mesopic light. Results The results show significant loss of CS (p <.001) and some loss in RF sensitivity (p <.01). The most sensitive measure of visual loss was CS.There was also a positive correlation between CAD thresholds as a measure of CS and improved DB control. Conclusion The results suggest that loss of visual function precedes structural changes in the retina and could be used as a means of detecting early structural changes in the retina that precede clinical diagnosis of retinopathy. Preliminary results also suggest that changes in CAD thresholds provide an objective way of monitoring the progress of DB and/or treatment outcome.
Differences in lens opacification in type 2 diabetic patients on oral anti‐diabetic medication or insulin therapy
Authors: WEGENER A , KREMER J , MÜLLER‐BREITENKAMP R , LASER H 
Published: September 2009

Abstract Purpose Evaluation of the effects of different anti‐diabetic therapies on light scattering in the lenses of type II diabetic patients compared to data from age‐matched normal patients. Methods The anterior eye segment of 53 patients (20 males and 33 females, mean age 68,23 years) from a private practice, 25 of which were on insulin therapy and 28 on oral anti‐diabetic therapies, were photographed with a Topcon SL‐45 Scheimpflug camera on Kodak Tmax 400. After standard development the images were digitized and evaluated in respect to density in defined lens layers. Statistical comparison was performed with regression analysis between diabetics and normal patients for 9 defined lens layers. Results Density data in lens layers 1 – 3 and 5 – 8 did not differ between the 2 treatment groups, whereas in layer 4 (anterior lens cortex) light scattering was significantly lower than in the group of patients on oral anti‐diabetic therapy. Gender had no influence on the data evaluated in this study. Conclusion In contrast to other, larger studies comparing different anti‐diabetic therapies, this study shows a trend indicating that insulin might provide a better protection of lens crystallins against non‐enzymatic glycosylation than oral anti‐diabetic medication. Further studies are needed to differentiate between various oral anti‐diabetic drugs.
Preoperative topical non‐steroidal anti‐inflammatory drug or steroid and clinical outcomes after trabeculectomy
Authors: STALMANS I , SPIELBERG L , VANGINDERDEUREN R , ZEYEN T , BREUSEGEM C 
Published: September 2009

Abstract Purpose To investigate the benefit of preoperative topical non‐steroidal anti‐inflammatory drug (NSAID) or steroid after trabeculectomy. Methods In this prospective randomized placebo‐controlled trial, 61 patients scheduled for trabeculectomy were randomized to one of 3 study medication groups: NSAID (ketorolac), steroid (fluorometholone) or placebo (artificial tears). Patients instilled one drop 4x daily for 1 month preoperatively and were examined on day 1, 2, at weeks 1, 2, and 4, and at months 3, 6, 12, 18 and 24 following trabeculectomy. Main outcome measures were incidence of postoperative interventions and IOP‐lowering medications; complete and qualified success rate; final IOP and relative IOP reduction. Results Fifty‐four eyes were entered for analysis. The percentage of patients requiring needling within the first year was 41% in the placebo, 6% in the NSAID and 5% in the steroid group (P = 0.006). The percentage of patients requiring IOP‐lowering medication at one year was 24% in the placebo, 18% in the NSAID and 0% in the steroid group (P = 0.054 overall; P = 0.038 for steroids versus others). Log‐rank test showed a significant (P = 0.019) difference in medication‐free survival curves between the different groups; patients in the steroid group needed significantly less medication (P = 0.007). The inter‐group differences in one‐year IOP, relative IOP reduction and success rates were not significant. Conclusion Topical ketorolac or fluorometholone for one month preoperatively was associated with improved trabeculectomy outcomes in terms of likelihood of postoperative needling. Within the steroid group, there was a significant reduced need for postoperative IOP‐lowering medication.
A new technique for diode laser cyclophotocoagulation: short term results
Authors: SURIANO M , STIRBU O , VILA ARTEAGA J 
Published: September 2009

Abstract Purpose To evaluate the efficacy of a new technique for diode laser cyclophotocoagulation in refractory glaucoma. Methods A consecutive case series of 8 eyes of 7 Caucasian patients who underwent gonioprism assisted diode laser cyclophotocoagulation (GADC). GADC with a peripheral corneal approach is a new surgical technique that employs a manual gonioprism, iris hooks, ophthalmic operating microscope and an 810 nm laser diode probe usually utilized for retinal photocoagulation Results The mean follow‐up time was 5.9 months (range 3 to 11 months). Mean intraocular pressure (IOP) (±SD) was reduced from 24.5±4.3 mmHg to 11.25±1.7 mmHg. The mean number of IOP lowering eye drops (±SD) was reduced from 2.0±0.8 preoperatively to 0.8±0.5 postoperatively. The visual acuity remained unchanged in 7 of 8 eyes (87.5%) and deteriorated in 1 of 8 eyes (12.5%). Early complications included IOP spike in one patient. No major complications were encountered. No eyes required repeat cyclophotocoagulation. Conclusion Gonioprism assisted diode laser cyclophotocoagulation with peripheral corneal approach appears to be an effective and safe surgical treatment of refractory glaucoma and has the advantage of no requiring of new endoscopic devices.
Refractive and biomechanical results of intrastromal ring segments for keratoconus
Authors: MICHAEL R , SANCHEZ C , MIKIELEWICZ M , DE LA PAZ MF , ALVAREZ DE TOLEDO J , BARRAQUER RI 
Published: September 2009

Abstract Purpose To analyse the refractive and biomechanical changes in the cornea after implantation of intrastromal ring segments. Methods The study included 43 eyes of 36 patients (mean age 38 years); 7 eyes had received Intacs® and 36 KeraRings®. Visual acuity, spherical equivalent, K readings, corneal hysteresis (CH) and corneal resistance factor (CRF) were measured pre‐op, at 6 and at 12 months post‐op. CH and CRF were derived from the Ocular Response Analyser (ORA). Results UCVA improved from 1.10 logMAR to 0.65 at 6 months and 0.62 at 12 months post‐op. BCVA improved from 0.32 logMAR to 0.25 at 6 months and 0.22 at 12 months post‐op. Spherical equivalent improved from ‐5.28 to ‐1.30 at 6 months and ‐1.85 at 12 months post‐op. Sim K improved from 5.81 to 3.64 at 6 months and 4.10 at 12 months post‐op. Mean K improved from 48.9 to 46.3 at 6 months and 46.7 at 12 months post‐op. All changes between pre‐op and 6 months post‐op were significant, but between 6 months and 12 months they were not. Pre‐op CRF (mean 6.37) and CH (mean 7.34) did not change significantly up to 12 months post‐op. Conclusion Intrastromal ring segments for keratoconus reduced the spherical equivalent refraction and improved the UCVA and BCVA at 6 months post‐op and remained stable up to 12 months. ORA's biomechanical factors CH and CRF did not changed up to 12 months post intrastromal ring segment implantation.
Opsoclonus
Authors: EGGENBERGER E 
Published: September 2009

AbstractOpsoclonus is a rare but important eye sign. It is the most extreme saccadic intrusion, and exists on a scale including ocular flutter. While flutter is horizontal back‐to‐back saccades without an inter‐saccadic interval, opsoclonus is multidirectional back‐to‐back saccades without an inter‐saccadic interval. Opsoclonus is often accompanied by myoclonus (“dancing eyes, dancing feet syndrome”), and may result from paraneoplastic (anti‐RI), brainstem encephalitis, parainfectious, toxicity, or other systemic conditions.
Corneal wavefront aberration measured by a rotary scanning system
Authors: FRANCO S , OLIVEIRA C , ALMEIDA JB 
Published: September 2009

Abstract Purpose Corneal wavefront aberration measurements are important in many areas such as refractive surgery, diagnosis and management of corneal disease as well as to understand the eye’s optical system. In this work the authors present the corneal anterior and posterior surface wavefront aberrations measured by an optical corneal tomographer that uses two Scheimpflug cameras attached to an innovative illumination system that allows a rotary scanning of the entire cornea. Methods The corneal wavefront aberration was computed from the corneal topographic height data of both corneal surfaces obtained by an innovative rotary scanning system. The topographic height data was computed from corneal optical sections obtained by illumination with a collimated beam expanded in a fan by a small cylindrical lens; this lens is provided with motor driven rotation in order to perform automated rotary scan of the whole cornea. This system has two stationary Scheimpflug cameras whose images are combined as if there was one virtual rotary camera synchronized with the cylindrical lens. Results After appropriate processing of the cameras images it is possible to produce true elevation maps and consequently, to compute wavefront aberrations of both corneal surfaces. In this work we present corneal aberrations measured with this system and explained how this is achieved. Conclusion This new optical system allows the measurement of corneal wavefront aberration as well as corneal thickness and 3‐D mapping of both corneal surfaces.
Optical qualities of the Boston keratoprosthesis
Authors: SAYEGH RR , AVENA DIAZ L , VARGAS‐MARTíN F , WEBB RH , DOHLMAN CH , PELI E 
Published: September 2009

Abstract Purpose To evaluate the optical characteristics of the Boston Keratoprosthesis (KPro) in relation to visual function. To determine glare sources and evaluate possible glare control. To explore the feasibility of fundus imaging. To examine the binocular consequences of implanting the device when the fellow eye has normal vision. Methods The computed and optical bench measured point spread function and corresponding modulation transfer function (MTF), as well as glare sources, were compared. A model eye construct was used to determine the relative impact of different sources of glare and its control. The effect of glare in eyes implanted with a KPro was measured with a Brightness Acuity Test (BAT) with and without a dark iris contact lens (dCL) for 8 eyes with Type I and 2 eyes with Type II KPro. Computed and measured visual fields were compared. The power of a lens that provides a wide field view of the fundus was calculated. Images with a fundus camera and lenses were obtained. Stereopsis was measured in 5 Type I KPro patients with an intact fellow eye. Results The computed and measured MTF for the KPro were found to be very close to the diffraction limit. Both the model eye and patients testing identified the hazy corneal graft as the main source of glare, which was controlled with a dCL. In 3 patients with an intact fellow eye, modest stereo acuity was gained with KPro implantation. Binocular visual field is not expanded when implanting a patient with normal fellow eye. Good image quality of the fundus is achieved in eyes with clear media. Conclusion Disability glare can be reduced with the use of a dCL. Implanting the KPro in a patient with an intact fellow eye only marginally improves visual function. Adequate fundus imaging can be obtained.