bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predicted corneal visual acuity in keratoconus as determined by ray tracing
Authors: Uçakhan Ömür Ö. 
Published: May 2003

Abstract.Purpose:  To evaluate the optical quality of the central anterior corneal surface in normal eyes and in eyes with keratoconus, and to investigate the accuracy of the predicted corneal visual acuity (PCVA) index as determined by ray tracing analysis.Methods:  Twenty keratoconus eyes with contact lens‐corrected visual acuity (VA) of 20/20 or better (11 patients, group A) and 20 eyes of 15 normal subjects (group B) were evaluated. After a detailed eye examination including measurement of pupil diameter, keratometry, topography and pachymetry, each subject eye was evaluated using ray tracing analysis with the Technomed C‐scan colour ellipsoid topometer, using basic software (Technomed GmbH, Baesweiler, Germany). The PCVA was determined for each patient, and the results were analysed comparatively using two‐sample t‐test, regression analysis and Pearson correlation analysis.Results:  The average best spectacle‐corrected VA was measured as 0.2 ± 0.2 logMAR (20/32) in group A and −0.1 ± 0.1 logMAR (20/16) in group B. The average PCVA measurements derived from ray tracing analysis for 3.0 mm, 3.5 mm and 4.0 mm pupil diameters were 0.06 ± 0.12 logMAR, 0.14 ± 0.13 logMAR and 0.21 ± 0.17 logMAR, respectively, in group A, and −0.14 ± 0.08 logMAR,−0.11 ± 0.09 logMAR and −0.09 ± 0.11 logMAR, respectively, in group B. There was good correlation between best corrected VA and PCVA in both groups for all pupil diameters measured (p < 0.007).Conclusion:  Predicted corneal visual acuity as determined by ray tracing analysis is useful for estimating best spectacle‐corrected VA in normal corneas and the effect of irregular corneal astigmatism on VA in eyes with mild to moderate keratoconus. Further studies are required to evaluate the efficacy of ray tracing in evaluation of aberrations of the optical system of the eye.
Oculometric features of hyperopia in children with accommodative refractive esotropia
Authors: Uretmen Onder , Pamukçu Kemal , Kose Süheyla , Egrilmez Sait 
Published: May 2003

Abstract.Purpose:  To determine the nature of hyperopia in children with accommodative refractive esotropia (ARE) by evaluating the relationships between corneal radius (CR), axial length (AL), age and equivalent spherical refraction (SEQ).Methods:  A total of 112 children with ARE were included in the study. The children underwent an overall ophthalmic examination including cycloplegic refraction, keratometry and ultrasonic AL measurement.Results:  Statistical analysis revealed a strong relationship between AL and SEQ (p < 0.001). A significant correlation was also found between AL and CR (p < 0.001). The relationship between AL and age was weak but statistically significant (p = 0.02). Multiple regression analysis, using SEQ as the dependent variable and CR, AL and age as independent variables, revealed that AL accounts for 43.5% of the variance, and the combination of CR and AL accounts for 60.9% of the variance.Conclusion:  Hyperopia is predominantly axial in nature in children with ARE. However, other refractive components are also involved in producing hyperopic refractive errors.
Characterization of vasomotion in porcine retinal arterioles
Authors: Hessellund Anders , Jeppesen Peter , Aalkjaer Christian , Bek Toke 
Published: May 2003

Abstract.Purpose:  To characterize vasomotion in porcine retinal arterioles in vitro using isobaric (pressure myograph) and isometric (wire myograph) methods.Methods:  Pressure myograph: 208 small porcine retinal arterioles (outer diameter 68 ± 4 μm) were studied under isobaric conditions in a double‐barrelled pipette system. Diameter changes of the arterioles were registered by video recordings. Wire myograph: 60 large porcine retinal arterioles (inner diameter 147 ± 1.6 μm) were studied under isometric conditions in a small vessel myograph for force measurements.Results:  The rates of success in initiating vasomotion were 7.2% using the pressure myograph and 43% using the wire myograph (p < 0.001). The small vessels studied under isobaric conditions oscillated with a frequency of 0.014 Hz and the episodes lasted 6.0 ± 1.0 min, whereas the large vessels under isometric conditions oscillated with a significantly faster frequency of 0.043 Hz and lasted 32.1 ± 4.9 min (p = 0.026).Conclusion:  Retinal vasomotion can be studied in vitro using both pressure myograph and wire myograph techniques. The wire myograph is superior to the pressure myograph in initiating and maintaining vasomotion in vitro.
A conservative blepharoplasty may be a means of alleviating dry eye symptoms
Authors: Floegel Ingrid , Horwath‐Winter Jutta , Muellner Klaus , Haller‐Schober Eva‐Maria 
Published: May 2003

Abstract.Purpose:  Patients with dermatochalasis often complain of dry eye symptoms. In a prospective study, the influence of upper eyelid blepharoplasty on dry eye symptoms, tear film parameters and ocular surface morphology was evaluated.Methods:  Patients with upper eyelid dermatochalasis were studied before and 3 months after upper eyelid blepharoplasty. Changes in ocular symptoms and physical examinations such as tear film break‐up time, Schirmer test without local anaesthesia, impression cytology of the bulbar conjunctiva and inflammatory reaction were recorded.Results:  Subjective dry eye symptoms were found in 11 patients (46%) preoperatively and in five patients (21%) postoperatively. Objective dry eye signs were present in eight patients (33%) before blepharoplasty and in nine patients (38%) 3 months postoperatively. Morphological findings did not change within the observation period. The inflammatory reaction shown by impression cytology decreased postoperatively.Conclusion:  Blepharochalasis may be associated with dry eye. Blepharoplasty might be a means of alleviating dry eye symptoms. The reason for this subjective alleviation might be due to reduced inflammatory reaction, changes in blink mechanism or the fact that patients are more confident about their appearance.
Efficacy and safety of timolol maleate/latanoprost fixed combination versus timolol maleate and brimonidine given twice daily
Authors: Stewart William C. , Stewart Jeanette A. , Day Douglas , Sharpe Elizabeth D. 
Published: May 2003

Abstract.Purpose:  To evaluate the efficacy and safety of the timolol maleate/latanoprost fixed combination (TLFC) given once each evening versus brimonidine and timolol solution given twice daily as concomitant therapy in primary open‐angle glaucoma or ocular hypertension patients.Methods:  Qualified subjects were begun on timolol alone twice daily for 1 month and then randomized to either TLFC or brimonidine and timolol concomitant therapy for 6 weeks. Patients were then switched to the other treatment regimen. Intraocular pressures (IOPs) were measured every 2 hours between 08 : 00 and 20 : 00 hours at baseline and at the end of periods 1 and 2.Results:  This study found that in 32 subjects the IOP diurnal curve on timolol alone (20.9 ± 2.8 mmHg) decreased to 17.9 ± 3.2 mmHg when patients were treated with TLFC and to 19.0 ± 2.4 mmHg when patients were treated with brimonidine and timolol (p = 0.02). Intraocular pressures at individual time‐points were statistically similar between the groups at the 08 : 00 trough and 2 and 4 hours after dosing. However, beyond 4 hours after dosing, TLFC‐treated subjects demonstrated a trend towards lower IOPs at each 2‐hour time‐point that was not statistically significant after a Bonferroni correction (p ≤ 0.05). The incidence of both solicited and unsolicited side‐effects was similar between groups.Conclusion:  This study suggests that TLFC given in the evening reduces the mean daytime diurnal IOP more than brimonidine and timolol given concomitantly twice daily.
Ocular complications and visual outcome in juvenile chronic arthritis: a 25‐year follow‐up study
Authors: Zak Marek , Fledelius Hans , Pedersen Freddy Karup 
Published: May 2003

Abstract.Objective:  Assessment of longterm ophthalmic outcome in juvenile chronic arthritis (JCA) with emphasis on visual acuity and identification of disease‐related parameters associated with rheumatic eye affection.Material:  Sixty‐five adults (52 females, 13 males) with a history of or still active JCA were assessed an average of 26.7 years after disease onset.Methods:  Cross‐sectional, longterm, follow‐up study including complete ophthalmological and rheumatological examinations.Results:  Evidence of ocular complications was found in 13 subjects (20%): 10 had had recurrent iritis, two band keratopathy, and one diplopia due to rheumatoid eye muscle involvement. The three single eyes with poor sight (<0.1) were all in the complication subgroup. Binocularly, all but one patient scored at least 6/9 as best corrected visual acuity; one, however, had severe glaucoma‐impaired visual fields. The refractive range was −8.12 to +6.0 D. There were no cases of keratoconjunctivitis sicca. Iritis was associated with early disease onset (p = 0.02), longer disease duration (p = 0.02) and a positive antinuclear antibodies (ANA) (p = 0.02).Conclusion:  Ophthalmic complications were recorded in 20% of the study group, primarily in ANA positive patients with pauciarticular onset JCA. In addition to the two patients with severely affected bilateral visual status (3%), one of the 65 patients had acquired unilateral blindness. Half of the complications were late in that they were first recorded after the age of 16 years. Otherwise, the findings were in keeping with other studies of visual prognosis using non‐selected series.
Lymphoid tumours of the ocular adnexa: a morphologic and genotypic study of 15 cases
Authors: Sigurdardottir Margret , Sigurdsson Haraldur , Barkardottir Rosa Björk , Kristjansdottir Sigrun , Agnarsson Bjarni A. 
Published: May 2003

Abstract.Purpose:  To examine all lymphoproliferative lesions of the ocular adnexa diagnosed in Iceland during 1983–2000 and to determine whether polymerase chain reaction (PCR) methods to determine clonality are helpful in characterizing these lesions.Methods:  All patients diagnosed with lymphoproliferative lesions in the ocular adnexa in the years 1983–2000 were included in the study. Polymerase chain reaction studies for clonality were performed on these lesions.Results:  Fifteen cases were identified. Seven were classified as inflammatory pseudotumour, one as lymphoid hyperplasia, four as atypical lymphoid hyperplasia and three as lymphoma. Of 12 cases examined by PCR, three were monoclonal for B‐cells (one lymphoma, one inflammatory pseudotumour and one atypical lymphoid hyperplasia) while the remaining lesions (including two lymphomas) appeared polyclonal.Conclusion:  The results of this study suggest that analysis of clonality by PCR methods may be of limited use in classifying lymphoproliferative lesions of the ocular adnexa as benign or malignant. These results underscore the importance of using several techniques when determining clonality.
Factor V Leiden and prothrombin gene G20210A mutations in ocular Behçet disease
Authors: Batioğlu Figen , Atmaca Leyla S. , Karabulut Halil Gürhan , Beyza Sayin Derya 
Published: May 2003

Abstract.Purpose:  To investigate genetic prothrombotic factors (factor V Leiden and prothrombin gene G20210A mutations) and their relation with retinal vascular occlusions in ocular Behçet disease.Methods:  Thirty Behçet patients were prospectively recruited into the study. Their mean age was 34.2 ± 8.3 years. All patients underwent complete ophthalmic examination and fluorescein angiography. Of the 30 patients, 15 (16 eyes) had retinal vascular occlusion. Patients were tested for the presence of factor V Leiden and prothrombin gene G20210A mutations by polymerase chain reaction. The results were compared with the frequencies of factor V Leiden in 285 and prothrombin gene G20210A mutation in 182 healthy members of the Turkish population.Results:  The prevalence of factor V Leiden mutation was significantly higher in ocular Behçet patients (12/30, 40%), compared with healthy control subjects (28/285, 9.8%) (p < 0.001). Of the 12 Behçet patients with factor V Leiden mutation, eight had retinal vascular occlusion. The prevalence of factor V Leiden was 53.3% (8/15) of the 15 patients with retinal vascular occlusion and 26.7% (4/15) of the remaining 15 patients without vascular occlusion. Prothrombin gene mutation was detected in none of Behçet patients compared with 2.7% (5/182) of the control group.Conclusion:  These data suggest that factor V Leiden may be an additional risk factor in ocular Behçet disease, whereas factor II mutations do not seem to be relevant.
Effects of thick Tenon's capsule on primary trabeculectomy with mitomycin‐C
Authors: Akarsu Cengiz , Önol Merih , Hasanrei̇soglu Berati 
Published: May 2003

Abstract.Purpose:  To investigate the effects of thick Tenon's capsule on primary trabeculectomy with adjunctive mitomycin‐C.Methods:  In this prospective interventional case series of 45 consecutive uncomplicated glaucoma patients, 45 eyes with thick Tenon's capsule underwent primary trabeculectomy with intraoperative mitomycin‐C (0.4 mg/ml for 3 min). Success was defined as intraocular pressure (IOP) ≤ 21 mmHg with (qualified) or without (complete) medications.Results:  The mean follow‐up period was 22.55 months. The mean preoperative IOP and number of medications were 28.91 ± 7.06 mmHg and 1.68 ± 0.73, respectively. The postoperative IOPs and the number of medications at all intervals were significantly lower than preoperative levels (p < 0.01 for each interval). The mean IOP was 11.03 ± 3.93 mmHg (12.17 ± 4.98 mmHg) at 24 months (12 months). Kaplan‐Meier survival analysis revealed a qualified success rate of 93.1% (95.6%) after 24 months (12 months). During follow‐up of the 45 eyes, 38 (84.4%) developed avascular thin‐walled bleb, seven eyes (15.6%) had hypotony (IOP < 6 mmHg), 14 eyes (31.1%) had a shallow anterior chamber, and one eye (2.2%) had endophthalmitis.Conclusions:  The use of mitomycin‐C is associated with high success rates and good IOP control even in the presence of thick Tenon's capsule. However, thick Tenon's capsule does not seem to eliminate the development of complications in eyes undergoing primary trabeculectomy with mitomycin‐C.
Measuring visual field progression in the Early Manifest Glaucoma Trial
Authors: Heijl Anders , Leske M. Cristina , Bengtsson Boel , Bengtsson Bo , Hussein Mohamed ,   EMGT Group
Published: May 2003

Abstract.Aims:  The Early Manifest Glaucoma Trial (EMGT) (316 eligible eyes) has used a new set of criteria to define visual field progression in glaucoma. This paper provides estimates of the amount of visual field worsening required to reach the EMGT definition of definite perimetric progression.Methods:  In the 148 eyes that reached definite progression, we first determined changes between baseline and the time of definite EMGT progression, both for mean deviation (MD) and for number of highly (p < 0.5%) significantly depressed test points in pattern deviation probability maps. Second, we studied whether such changes depended on baseline MD, intraocular pressure (IOP), age and time to progression, all of which are factors that affect the rate of field progression.Results:  In eyes reaching progression, the mean change in MD from baseline was −1.93 dB (SE ± 0.20) and the mean change in number of significant points was +4.85 (SE ± 0.35). These changes did not show linear dependency on baseline MD, IOP or time to progression.Conclusions:  The average amount of field deterioration needed to reach EMGT visual field progression has been measured and expressed in more conventional units (i.e. a loss of about − 2dB in MD and an increase in about five highly significant points). These estimates will facilitate the clinical interpretation of the results of EMGT.
Frequency doubling technology and high‐pass resolution perimetry in glaucoma and ocular hypertension
Authors: Kalaboukhova Lada , Lindblom Bertil 
Published: May 2003

Abstract.Purpose:  To study the correlation between frequency doubling technology perimetry (FDT) and high‐pass resolution perimetry (HRP) in eyes with primary open‐angle glaucoma, suspect glaucoma, ocular hypertension, and in normal eyes.Patients and Methods:  Ninety‐four patients (162 eyes) were studied. Visual fields were assessed by HRP, FDT screening C‐20–5 and FDT threshold C‐20 programs. In eyes with a discrepancy between the test results, a comprehensive clinical examination was performed, including optic disc photography and Heidelberg retinal tomography (HRT).Results:  There was a strong correlation between HRP global deviation and the FDT mean deviation (for FDT threshold C‐20 test), and between HRP score and FDT score (for FDT screening C‐20–5 ). The correlation coefficients were r = −0.83 and r = 0.77, respectively. In all, 75 eyes (46.3%) had normal HRP and FDT screening results, while 67 eyes (41.4%) showed abnormal results in both tests. In 12 eyes (7.4%) HRP was within normal limits while FDT screening was abnormal. Seven of these eyes were judged to have glaucoma; three of them had converted from ocular hypertension to glaucoma. In eight eyes (4.9%) HRP was abnormal while FDT screening was normal. Three of these were judged to have glaucoma. Thus, the sensitivity and specificity of the FDT screening test for the detection of glaucoma were 91.7% and 87.8%, respectively.Conclusion:  There was a strong correlation between FDT threshold C‐20, FDT screening C‐20–5 and HRP test results. Frequency doubling technology perimetry C‐20–5 represents a good screening test for the detection of optic nerve damage in open‐angle glaucoma.
Relationship between optic nerve head microcirculation and visual field loss in glaucoma
Authors: Yaoeda Kiyoshi , Shirakashi Motohiro , Fukushima Atsushi , Funaki Shigeo , Funaki Haruko , Abe Haruki , Tanabe Naohito 
Published: May 2003

Abstract.Purpose:  To study the relationship between optic nerve head blood flow velocity and visual field loss in patients with primary open‐angle glaucoma (POAG) and normal tension glaucoma (NTG).Methods:  This study included 44 eyes of 44 patients with POAG and 44 eyes of 44 patients with NTG. To evaluate optic nerve head blood flow velocity, the square blur rate (SBR) was measured by means of laser speckle flowgraphy. The correlation between SBR and Humphrey visual field indices was evaluated with linear regression analysis.Results:  In the NTG group, the average SBR at the superior and inferior temporal neuroretinal rim was positively correlated with mean deviation (MD) (r = 0.349, p = 0.020). The SBR at the superior or inferior temporal neuroretinal rim was positively correlated with the sum of the total deviations in the corresponding hemifields (r = 0.299, p = 0.049; r = 0.354, p = 0.019, respectively). The correlations between SBR and MD did not differ statistically between the NTG and POAG groups; however, no significant correlation between SBR and visual field indices was observed in the POAG group.Conclusion:  These results suggested that the change in the circulation of the optic nerve head may be related to visual field damage in the NTG group but may be less involved in visual field damage in the POAG group.
Topical medication interferes with face‐down positioning after macular hole surgery
Authors: Krohn Jørgen 
Published: May 2003

Abstract.Purpose:  To investigate whether different procedures of topical medication interfere with postoperative face‐down positioning and thereby influence the anatomical success rate of macular hole surgery.Methods:  A total of 39 consecutive eyes with macular holes were operated with vitrectomy and fluid‐gas exchange, followed by face‐down positioning for 1 week. Postoperatively, the procedures for topical medication differed between two consecutive groups of patients. In the first group (16 patients), a conventional postoperative regimen of topical antibiotics and steroids was administered as eye drops six times daily. In the second group (23 patients), topical medication was administered as ointments once daily, while the patients kept their heads straight forwards and looked slightly downwards.Results:  The macular hole closed successfully in 10 (62.5%) of the 16 eyes in the eye drop group, and in 21 (91.3%) of the 23 eyes in the ointment group (p < 0.05).Conclusion:  The present study indicates that frequent postoperative administration of eye drops reduces the success rate of macular hole surgery. To prevent patients from looking upwards during the instillation of topical antibiotics and steroids, the use of ointments is recommended.
Amniotic membrane as support for human retinal pigment epithelium (RPE) cell growth
Authors: Capeáns Carmen , Piñeiro Antonio , Pardo María , Sueiro‐López Catalina , Blanco María José , Domínguez Fernando , Sánchez‐Salorio Manuel 
Published: May 2003

Abstract.Purpose:  The aim of this work was to culture human retinal pigment epithelium (hRPE) cells over human amniotic membrane (hAM). Human AM was studied for its viability as an adequate support for transplantation of an hRPE cell monolayer with preserved cell polarity to the subretinal space.Methods:  Human AM was obtained from pregnant women during caesarean section. The hAM was sectioned and the pieces were fixed to culture dishes. Human RPE cells were cultured from adult corneal donors and were seeded over hAM. Phase‐contrast photographs were obtained. Selected specimens were processed by transmission electronic microscopy (TEM).Results:  The attachment and growth of hRPE cells over hAM was observed. Human RPE cells constituted tight colonies that maintained epithelial phenotype. Using TEM, we identified a monolayer of hRPE cells, with cuboidal to spheroidal morphology. These cells showed integration with the substrate and cell−cell contacts were detected.Conclusion:  Amniotic membrane may be a suitable substrate for hRPE growth. Further studies are required in order to determine the viability of hRPE on hAM in the subretinal space.
Identification of candidate genes for schizophrenia based on natural resistance to infectious diseases
Authors: Brown James S 
Published: May 2003

Background:Identification of candidate genes for schizophrenia may be more successful than genome screens as the latter have not found consistent linkages.Objective:To assist in the gene search, a model of schizophrenia based on resistance to infectious diseases, rather than susceptibility, is proposed. The theory blends the geography of schizophrenia with the assumption that genes that cause schizophrenia likely evolved and persist from selection pressure. The theory includes the notion that schizophrenia enhances biological survival at the cost of psychological and social functioning.Method:To demonstrate the utility of using this model, the Medline literature was searched for resistance genes, mostly identified in mice.Results:Based on homologous locations in the human genome, these resistance genes are shown to be located in human chromosome regions linked significantly, in at least one genome screen, with schizophrenia or some physiologically related function or condition associated with schizophrenia.Conclusions:The infectious disease resistance theory of schizophrenia is offered as a viable model for understanding the origins of schizophrenia. The theory also allows for the inclusion of persistent infections, seasonal variability and translational pathophysiology to contribute to the etiology of schizophrenia.