Biomedical subjects

V Polo

Publications and source records attributed to V Polo.

At least 19 recordsLinked to original sources

PubMed2006

[Sector-based analysis of the distribution of the neuroretinal rim by confocal scanning laser in the diagnosis of glaucoma].

PURPOSE: To evaluate the diagnostic ability of the Moorfields regression analysis (MRA; neuroretinal rim sector-based analysis) by means of confocal scanning laser. METHODS: 200 eyes were included in this study: 101 normal subjects and 99 glaucoma patients (standard automated perimetry with glaucomatous defects -MD or CPSD with p<0.02 or a cluster of three or more points with p<0.05 or a cluster of two or more points with p<0.01 or abnormal Glaucoma Hemifield Test). All subjects underwent a full ophthalmic evaluation, visual field evaluation by means of a Humphrey Field Analyzer, 24-2 full threshold strategy, and optic disc topography by Heidelberg retina tomograph (HRT-II). The outcome parameters were sensitivity and specificity of the MRA for each sector. RESULTS: The highest sensitivity in detecting structural defects based on MRA (p<0.05) was observed in the nasal-superior sector (48%) and nasal-inferior sector (45%); however the highest specificity was found in the temporal-superior (98%) and inferior (98%) sectors. The highest sensitivity for MRA (p<0.01) was found in the temporal-inferior sector (31%) and nasal-superior sector (30%) while the temporal-superior and inferior-sectors showed the highest specificity (100%). The diagnosis of glaucoma based on the presence of any sector alteration showed sensitivity figures of 67% with p<0.05 and 46% with p<0.01 and specificity values of 84% with p<0.05 and 96% with p<0.01. CONCLUSIONS: The analysis of the distribution of the neuroretinal rim by means of HRT-II contributes effectively to the diagnosis of glaucoma based on perimetry in a sample derived from a Spanish population.

Adult↗

PubMed2006

[Reproducibility of optic nerve head and retinal nerve fiber layer thickness measurements using optical coherence tomography].

PURPOSE: To evaluate the reproducibility of repeated quantitative measurements of optic nerve head topography and retinal nerve fiber layer thickness. METHODS: This study included 32 normal subjects, 41 patients with ocular hypertension and 33 patients with glaucoma. The study groups were defined by the intraocular pressure levels, optic disc stereo-photographs and perimetric performance. Optic disc and retinal nerve fiber layer assessments were performed by ocular coherence tomography (OCT III, Zeiss Instruments). OCT examination was repeated three times in each subject and the coefficient of variability was elaborated for each parameter and group of the study, and compared among them. RESULTS: The average retinal nerve fiber layer thickness measurement showed the best reproducibility figures with a coefficient of variability of 5.9%. The inferior quadrant and the 10, 6 and 7 clock-hours (coefficients of variability 6.3%, 7.4%, 7.5% and 8.6% respectively) showed higher reproducibility. The optic nerve head assessment showed the best reproducibility for the cup-to-disc ratios (vertical, horizontal and area ratios), with a coefficient of variability of 5.0%, 4.2% and 6.6% respectively. Although differences among groups were barely statistically significant, the glaucoma group showed coefficients of variability higher than the other two groups. CONCLUSIONS: Optic nerve head analysis and retinal nerve fiber layer thickness can be reproducibly assessed by OCT. The reproducibility of the device supports its potential use for ocular hypertension follow-up, although its use in glaucoma patients may present difficulties in some parameters.

Female↗

PubMed2006

[Diagnostic ability of stratus optical coherence tomography (OCT) in pre-perimetric glaucoma diagnosis].

OBJECTIVE: To compare retinal nerve fiber layer (RNFL) measurements performed with Stratus OCT 3000 in normal, ocular hypertensive, pre-perimetric and glaucomatous eyes. METHODS: 98 normal subjects, 156 ocular hypertensives with short-wavelength automated perimetry (SWAP), 21 ocular hypertensives with altered SWAP (pre-perimetric glaucoma) and 66 glaucomatous eyes were included in the study. Diagnostic groups were classified based on intraocular pressure, optic nerve head appearance, achromatic automatic perimetry and SWAP. RNFL parameters were obtained using a Stratus OCT 3000 (Humphrey Zeiss instruments). RNFL measurements were compared among the groups. RESULTS: RNFL average thickness, superior, inferior and nasal quadrant thickness, and each 12 clock-hour positions except for H9, H10 and H11 showed significant differences between glaucomatous and pre-perimetric glaucoma eyes. RNFL average thickness, inferior quadrant and H10 clock-hour position showed significant differences between normal and ocular hypertensive subjects. Pre-perimetric glaucomas and ocular hypertensives showed differences in H11 clock-hour position exclusively. CONCLUSION: RNFL measurements performed using Stratus OCT showed differences between the study groups. OCT may be as useful as SWAP in early glaucoma diagnosis.

Female↗

PubMed2006

[Diagnostic usefulness of optical coherence tomography (OCT), scanning laser tomography (HRT-II) and laser polarimetry (GDx) in open-angle glaucoma].

PURPOSE: To evaluate the diagnostic ability of three digital imaging technologies (HRT-II, OCT and GDx VCC) in detecting glaucomatous damage. METHODS: A total of 427 eyes from 427 subjects were included in this cross-sectional study. Each subject was classified as healthy, ocular hypertensive or glaucomatous, according to intraocular pressure levels, standard automated perimetry and optic disc morphology. All of them underwent examination by means of HRT, OCT and GDx VCC. Receiver operating characteristic (ROC) curves were plotted and sensitivities at fixed specificities (85% and 95%) were calculated for each parameter assessed. RESULTS: The parameters with the higher diagnostic ability were: FSM discriminant function from HRT-II (AUC=0.899), retinal nerve fiber layer average thickness from OCT (AUC=0.929) and NFI from GDx VCC (AUC=0.879), with no statistically significant differences between them. CONCLUSION: The HRT-II, OCT and GDx VCC provide measurements of the retinal nerve fiber layer and the optic nerve head with high discriminating ability in open-angle glaucoma.

Aged↗

PubMed2005

[Malignant glaucoma following combined Ahmed valve implant and phacoemulsification surgery for chronic angle-closure glaucoma].

CASE REPORT: Simultaneous Ahmed valve implant, combined with phacoemulsification cataract surgery, is a useful therapeutic option for patients with chronic angle-closure glaucoma, when conventional filtering surgery fails. This combined approach permits both control of intraocular pressure and early recovery of visual function. We report the results in five patients successfully treated with this combined procedure, two of whom developed early postoperative malignant glaucoma. DISCUSSION: Predisposing anatomic features in patients with chronic angle-closure glaucoma, associated with sudden anterior chamber decompression and increased postoperative inflammation, may facilitate the development of malignant glaucoma following combined glaucoma implant and phacoemulsification surgery.

Aged↗

PubMed2003

[Benefit of scanning laser ophthalmoscopy for detecting retinal nerve fiber layer defects in patients with intraocular hypertension].

PURPOSE: To compare the ability to identify RNFL alterations between standard images and SLO images in a group of patients suffering from ocular hypertension. METHODS: We evaluated RNFL in sixty patients with ocular hypertension and with normal perimetry, by using standard photography and SLO. Two different independent observers evaluated the images on two different ocassions. RESULTS: We studied 118 eyes, twelve eyes were rejected because of the low quality of the images. Four cases of diffuse atrophy and five patients with wedge shaped defects were observed using both methods. Statistical analysis showed no differences between both exploration techniques or between observers. CONCLUSIONS: RNFL study with SLO seems to be at least as reliable as standard photography as a method to evaluate RNFL defects. SLO has also proved to be much easier, and faster than traditional methods.

Female↗

PubMed2001

Optimum criteria for short-wavelength automated perimetry.

OBJECTIVE: To determine the optimum perimetric criteria for short-wavelength automated perimetry on the basis of probabilistic maps that best discriminate between normal and glaucoma. DESIGN: Comparative cross-sectional study. PARTICIPANTS: Ninety-five glaucomatous eyes and 128 normal eyes were included in the study. INTERVENTIONS: The subjects underwent retinal nerve fiber layer photographic evaluation and short-wavelength automated perimetry. MAIN OUTCOME MEASURES: A probabilistic map of differential points for short-wavelength automated perimetry was elaborated, and the number of altered points was calculated for each visual field and level of significance (95%, 98%, 99%, and 99.5%). RESULTS: The presence of a cluster of four or more points outside 95% normal probability limit showed a good combination of sensitivity and specificity. At deeper levels, P: < 1% and P: < 0.5%, the best combination is achieved with three points outside the normal probability limits. CONCLUSIONS: The optimum criterion to define glaucomatous abnormalities in short-wavelength automated perimetry is the presence of a cluster of four points lower than P: < 5% or a cluster of three points lower than P: < 1%.

Adult↗

PubMed2001

Latanoprost versus combined therapy with timolol plus dorzolamide: IOP-lowering effect in open-angle glaucoma.

PURPOSE: To compare the effect on intraocular pressure of latanoprost versus timolol plus dorzolamide in open-angle glaucoma. METHODS: Thirty-five patients with open-angle glaucoma were randomized, 18 to latanoprost once daily and 17 to timolol plus dorzolamide twice daily. Intraocular pressure and ocular side effects were recorded at baseline, and after 2 weeks and 3 months of treatment. RESULTS: Latanoprost reduced the intraocular pressure 1.09 and 1.58 mm Hg more than timolol plus dorzolamide after 2 weeks and 3 months of treatment, respectively. These differences were statistically significant (p<0.05) at the end of the study. After 3 months of treatment, 32.3% of the eyes in the latanoprost group reduced the intraocular pressure in 30% or more with respect to baseline, while 15.6% of the eyes in the timolol plus dorzolamide group achieved this reduction. CONCLUSIONS: Latanoprost administered once daily reduced the intraocular pressure at least as well as timolol plus dorzolamide twice daily in patients with open-angle glaucoma.

Adrenergic beta-Antagonists↗

PubMed2001

Functional and structural measurements in a multifactorial glaucoma risk model.

PURPOSE: To evaluate the relationship between a multifactorial probability risk model of developing glaucomatous visual field defects and the assessment of the retinal nerve fiber layer (RNFL) and short-wavelength automated perimetry (SWAP) in glaucoma suspects. METHODS: 157 eyes of 157 glaucoma suspects were included in the study. The risk of developing glaucomatous defects was assessed by applying a multifactorial model that included intraocular pressure, vertical cup-to-disk ratio, age and family history. Photographs of the RNFL and SWAP were performed. RESULTS: The SWAP was abnormal in 54 cases (34.3%); 21% of abnormal perimetries were obtained in the low-risk group, 37% in the moderate risk group and 56% in the high risk group. The nerve fiber layer evaluation in the different risk stages showed a pattern similar to the results obtained with SWAP. Multiple regression analyses, performed with the four variables included in the model with SWAP and RNFL evaluation, showed the relationship between the risk factors and the presence of glaucomatous damage--evaluated by RNFL and SWAP (p<0001). CONCLUSIONS: The probability model showed a good correlation between the risk scale and the RNFL and SWAP assessment.

Adult↗

PubMed2001

Stillbirth pattern in an isolated mediterranean population: La Alpujarra, Spain.

This study attempted to analyze the effect of several factors on the stillbirth pattern in a relatively isolated rural population, La Alpujarra (Spain), during the first half of the 20th century. The study was a retrospective analysis from a total sample of 2199 births to 525 mothers, allowing for birth year of mother, maternal age, parental inbreeding, family size, birth order, sex, single/twin delivery, and birth interval. Binomial probability distribution of stillbirths provided no evidence for any significantly increased risk in relation to family size. Analysis of covariance (ANCOVA) of stillbirth risk in affected families indicated a significant effect for sex of the child, parental consanguinity, and birth year of mother. Logistic regression showed increased risk in twin delivery and pregnancy order one, but not for birth order other than one. Multivariate analysis of variance (MANOVA) testing for differences between affected and unaffected families supported a temporal decrease of stillbirths during the period studied. Although the birth interval average was significantly shorter in affected families (p < 0.0001), this association did not hold, in a more detailed analysis, for individual intervals in these families (p = 0.20). There was no significant effect of maternal age on stillbirths in the whole sample or limited to first pregnancies. These results suggest that birth order one and twin delivery were the main determinants of the stillbirth pattern in La Alpujarra. Furthermore, our data indicate that the decline in stillbirth rate began before medical facilities for perinatal care became available, which was not until after 1950. The temporal decrease in stillbirth rates may therefore be related to an increasing social attention to deliveries rather than to prenatal care medical facilities.

Adult↗

PubMed2001

[Early glaucomatous changes in neuroretinal rim shape].

PURPOSE: To assess the differences in neuroretinal rim shape in ocular hypertensive patients (normal white-white automated perimetry) with and without perimetric injury in the short wave length automated perimetry (blue-yellow). MATERIAL AND METHODS: 72 eyes from 72 hypertensive ocular patients with normal achromatic automated perimetry examination were included. Forty eyes had normal short wave length automated perimetries while 32 subjects presented an abnormal condition. The neuroretinal rim morphology was quantified by means of a planimetric study from the papillary images obtained with confocal laser scanning. RESULTS: The subjects with abnormal blue-yellow perimetry showed a decrease in the neuroretinal rim area in the inferior and temporal positions. The differences were significant (p<0.05) at the 9 o'clock position (below the middle line) and almost significant (p<0.10) at the 10 o'clock position. CONCLUSIONS: There are differences in the neuroretinal rim shape in ocular hypertensive subjects with normal achromatic perimetry according to whether there are abnormalities in the blue-yellow perimetry.

Adult↗

PubMed2001

[Neuroretinal rim width in normal, hypertensive and glaucomatous subjects].

PURPOSE: To determine width and shape of neuro-retinal rim in normal hypertensive subjects and patients with glaucomatous damage. MATERIAL AND METHOD: Patients underwent a perimetry and a photographic retinal nerve fiber evaluation. Patients were divided in three groups: normal subjects (n=34), ocular hypertension subjects (n=38) and glaucoma patients (n=34). Neuro-retinal rim was measured using 40 degrees stereoscopic photographs with center in the optic nerve head based on a biomorphometry technique. RESULTS: In normal subjects neuro-retinal rim appeared wider in the lower pole, followed by the upper, nasal and temporal aspects. Optic nerve fiber layer showed a decreased thickness in hypertensive and glaucoma patients, particularly in sectors of the temporal aspect of the optic nerve (p<0.05). CONCLUSIONS: A Planimetry study of the optic nerve is able to detect alterations in normal neuro-retinal rim configuration and can as well detect thinning of the rim, particularly in temporal, upper and lower areas.

Adolescent↗

PubMed2000

Status signalling, metabolic rate and body mass in the siskin: the cost of being a subordinate.

The higher metabolic rate of dominant individuals, found in different species, has been interpreted as the cost that prevents subordinates from cheating by adopting large badges of status. However, an alternative prediction for status-signalling species, in which subordinates may recognize dominants, is that subordinates have the higher metabolic rate because of the greater stress of locating and actively avoiding aggressive interactions with them. In this study, the size of the black bib of the siskin, Carduelis spinus, which is a badge of dominance, was negatively correlated with metabolic rate in daylight, even when controlling for the bird's activity level in the respirometer chamber and its body mass. The size of the black bib, however, was not correlated with metabolic rate in darkness. This suggests that the difference between dominance classes is not related to intrinsic physiological differences, but that subordinates are more susceptible to stressful conditions. When controlling for metabolic rate, a positive correlation appeared between dominance status and body mass. This stresses the importance of knowing the effects of social status on energy requirements for understanding the relationship between body mass and dominance. We conclude that maintaining a high social status may be more stressful to subordinates than to dominant birds. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗

PubMed2000

Anatomic results and complications in a long-term follow-up of pneumatic retinopexy cases.

BACKGROUND: The use of pneumatic retinopexy is controversial because 1) intraocular gas could increase the risk of proliferate vitreoretinopathy and 2) it has been reported to achieve low rates of success after a single procedure. METHODS: A total of 219 consecutive cases of SF6 pneumatic retinopexy were reviewed retrospectively. The follow-up period ranged from 2 to 5 years. RESULTS: A total of 179 (81.73%) of 219 eyes were treated successfully with a single procedure. The success rate increased with reoperations to 98.89%. Preoperative factors related to primary failure or redetachment were aphakia or pseudophakia (P = 0.0058) and breaks localized on horizontal meridia (P = 0.0305). Cryopexy was significantly associated with failure (P = 0.0007). A total of 31.05% of eyes showed early complications. The most frequent incidence was delay in subretinal fluid reabsorption (36.76%), followed by new breaks (26.47%). Late complications were observed in 6.84% of the eyes (six eyes with macular pucker, three with new retinal detachments, three with cataracts, and three with new breaks without detachment). CONCLUSIONS: Failures of pneumatic retinopexy were related to lens status, localization of the break, and cryopexy. The occurrence of early and late complications was similar to that in other procedures.

Cryosurgery↗

PubMed2000

Determinants of birth interval in a rural Mediterranean population (La Alpujarra, Spain).

The fertility pattern, in terms of birth intervals, in a rural population not practicing contraception belonging to La Alta Alpujarra Oriental (southeast Spain) is analyzed. During the first half of the 20th century, this population experienced a considerable degree of geographical and cultural isolation. Because of this population's high variability in fertility and therefore in birth intervals, the analysis was limited to a homogenous subsample of 154 families, each with at least five pregnancies. This limitation allowed us to analyze, among and within families, effects of a set of variables on the interbirth pattern, and to avoid possible problems of pseudoreplication. Information on birth date of the mother, age at marriage, children's birth date and death date, birth order, and frequency of miscarriages was collected. Our results indicate that interbirth intervals depend on an exponential effect of maternal age, especially significant after the age of 35. This effect is probably related to the biological degenerative processes of female fertility with age. A linear increase of birth intervals with birth order within families was found as well as a reduction of intervals among families experiencing an infant death. Our sample size was insufficient to detect a possible replacement behavior in the case of infant death. High natality and mortality rates, a secular decrease of natality rates, a log-normal birth interval, and family-size distributions suggest that La Alpujarra has been a natural fertility population following a demographic transition process.

Adult↗

PubMed2000

[Reproducibility of planimetric optic nerve head analysis with scanning laser ophthalmoscope].

PURPOSE: To determine the variability of disc and cup area measurements in digital images obtained with scanning laser ophthalmoscope. METHODS: 10 sets of images of 4 optic discs (normal, myopic, ocular hypertensive and glaucomatous) were obtained with the Rodenstock scanning laser ophthalmoscope. Images focused at different depths were used by 2 operators (with and without experience in planimetry) to determine the disc and cup areas by means of an image analysis program (Visilog). This study was performed in 10 images obtained from the same optic nerve (inter-image analysis) and 10 times in the same image of each optic nerve (intra-image analysis). RESULTS: The variability of all the measurements was under 5%. Disc area measurements were lower than cup area determination. The experienced operator obtained lower variability. The myopic optic disc images were less reproducible than the other groups of images. CONCLUSIONS: The planimetric analysis of optic nerve head digital images obtained with scanning laser ophthalmoscope is reproducible and allows quantification of optic disc areas.

Humans↗

PubMed2000

[Inhibitory effect of alpha tocopherol succinate on fibroblast wound healing].

PURPOSE: To evaluate and compare the effect of acid tocopherol succinate (ATS) on fibroblast migration and proliferation. METHODS: In vitro wound repair was determined in confluent fibroblast monolayer. Conjunctival fibroblasts were incubated with serum-deprived medium for 24 hours. After this time an artificial wound was made and the cells were incubated with fresh medium plus the doses of ATS to be tested. The cell free area was monitored at 0, 18, 24 and 48 hours. Groups of treatment: Group 1: ethanol 0.1%. Group 2: ATS 25 microM dissolved in ethanol (final concentration 0.1%) Group 3: ATS 50 microM in ethanol 0.1%. Each experiment was carried out in triplicate and repeated 4 times. RESULTS: There were no differences among the groups during the first 24 hours. ATS showed significantly larger cell-free area at 48 hours. There were no signs of cellular toxicity. CONCLUSIONS: 25 microM and 50 microM ATS inhibit fibroblast proliferation without cellular toxicity.

Cell Division↗

PubMed2000

[Inhibitory effect of nicardipine on fibroblast proliferation mechanisms].

PURPOSE: To assess the effect of nicardipine (NCP) on fibroblast migration and proliferation, and its cellular toxicity. METHODS: In vitro wound repair was assessed in confluent fibroblast monolayer. Mechanical round wounds were performed in the monolayers and the cultures were incubated in fresh media plus NCP. The cell-free area was monitored after 0, 18, 24 and 48 hours. Groups of treatment: Group 1, Sham. Group 2, NCP 10(-4)M in the media. Group 3, NCP 7.5x10(-5)M. Group 4, NCP 5x10(-5)M. Group 5, NCP 2.5x10(-5)M. Group 6, NCP 10(-5)M. Group 7, NCP 10(-6)M. Group 8, NCP 10(-7)M. Group 9, NCP 10(-3)M. Each experiment consisted of three tests that were repeated four times. RESULTS: The fibroblast migration and proliferation was inhibited at 5x10(-5)M or higher doses. The proliferation after 48 hours with NCP 2.5x10(-5)M was statistically inferior to the control group and groups 7, 8, and 9. NCP 5x10(-5)M or higher doses showed cellular atypia and cell death. CONCLUSIONS: NCP effectively inhibits fibroblastic wound repair process at doses 2.5x10(-5)M and shows toxicity at doses over 5x10(-5)M.

Calcium Channel Blockers↗