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J C Pastor

Publications and source records attributed to J C Pastor.

At least 19 recordsLinked to original sources
PubMed2006

[Cholesterol, alpha-tocopherol, and retinoid concentrations in silicone oil used as a vitreous substitute].

OBJECTIVE: To verify the existence of organic lipophylic compounds in silicone oil extracted from human eyes following its use for previous retinal detachment, and to determine the intraocular permanence time of these substances in the oil. METHODS: Concentrations of retinoic acid, retinol, retinal, cholesterol and alpha-tocopherol were detected by HPLC in 23 samples of silicone oil extracted from patients with complicated retinal detachments. The time interval between the time of injection of the silicone oil and the subsequent assessment varied from 3 to 50 months (the permanence time). RESULTS: All tested compounds were found in the samples, but these were most commonly cholesterol and less frequently alpha-tocopherol. There was an inverse relationship between retinoic acid concentration and age (p=0.023), and a direct relationship between cholesterol concentration and permanence time (p=0.0008) at least up to 20 months. CONCLUSIONS: These findings confirm that silicone oil is not an inert substance but is capable of extracting lipophylic compounds from the intraocular tissues. There is a clear linear elevation of cholesterol levels with increased intraocular permanence time. This finding could be used to further establish a safe permanence time for intraocular silicone oil used in ophthalmologic surgery. More studies with larger samples are warranted to evaluate this further.

Adolescent↗
PubMed2006

[National survey on vitreo-retinal surgery and the management of rhegmatogenous retinal detachments in Spain. Project retina 2].

PURPOSE: To obtain information throughout Spain on the current management of vitreo-retinal surgical diseases, the number of ophthalmologists involved in retinal surgical diseases care, and the urgent management of retinal detachments. METHODS: A 30 item questionnaire was sent by mail, on two separate occasions, to the heads of Ophthalmology Departments of 276 centers in Spain. RESULTS: A total response rate of 48.2% was achieved, however the answers from private centers represented only 9.4% of the total so these were excluded from the analysis. The centers most likely to respond were those in Teaching Hospitals (TH) (52.3%). Of these, 64% of hospitals responded that, in the last year, they performed pars plana vitrectomies (PPV) and 70% performed more than 100 PPVs in the year. In all, 77% of the centers that performed PPVs had also performed them urgently. A total of 75% of hospitals indicated that they had ophthalmologists mainly dedicated to retinal diseases care, with a median of 2 specialists per center, with this representing 23% of their total staff. Retinal surgery was performed by general ophthalmologists in 11.5% of centres. Only 40.3% of hospitals audit their results (37.5% TH). CONCLUSIONS: Despite the existence of a relatively low response rate, as well as some biases and methodological problems, data on the management of retinal surgical disease has been obtained for the first time at a national level. This data will facilitate later studies and must be taken into consideration in improving the planning and adequate management of these diseases in Spain.

Humans↗
PubMed2005

Interaction between surgical procedure for repairing retinal detachment and clinical risk factors for proliferative vitreoretinopathy.

PURPOSE: To asses risk factors of proliferative vitreoretinopathy (PVR) and a model for predicting it. METHODS: Observational, case-control. 335 patients with non-complicated retinal detachment (RD) were included: 134 developed PVR (Cases); 201 patients did not (Controls). Risk factors for PVR were identified by multivariate analysis. Influence of variables was assayed according to the surgical approach. By logistic regression analysis a model to predict the risk of developing PVR and odds ratio (OR) values for each clinical factor were estimated. RESULTS: Risk was higher in patients > 70 years and with intraocular pressure lower than 14 (OR: 3.84; CI 95%: 2.04-7.30) and in retinal breaks larger than "1 clock hour" (OR: 2.54; CI: 1.28-5.05), extended retinal detachments (OR: 4.01; CI: 1.98-8.10) and reinterventions (OR: 1.55; CI: 1.14-9.22). Scleral surgery also was a risk factor (OR: 3.89; CI: 2.12-7.14) and aphakia/pseudophakia when scleral surgery is performed (OR: 3.33; CI: 1.54-7.22). A model to predict PVR was proposed with these results. CONCLUSIONS: Surgical approach modifies risk factors of PVR, and should be taken into account to improve the models for predicting it.

Adolescent↗
PubMed2003

[Clinical risk factors for postoperative proliferative vitreoretinopathy (PVR). A prospective study].

PURPOSE: To identify clinical risk factors for development of postoperative PVR, to determine the incidence of this complication and its time of onset by a prospective multicentric study. METHODS: A multicentric and prospective study of 223 patients with rhegmatogenous retinal detachment (RD) was conducted. Logistic regression analysis was used to identify risk factors for PVR among 83 variables related to preoperative, intraoperative and postoperative characteristics. RESULTS: 22 out of 223 RD developed PVR (incidence 9.9%, confidence interval 95%: 5.9-13.9). After logistic regression analysis, four variables showed an odds ratio higher than 1.0 (RD affecting 4 quadrants, cryopexy, aphakia/pseudophakia and those RD in which an encircling band was implanted). None of these factors showed a < > value lower than 0.05. Most of postoperative PVR (77.2%) appeared in the first month after surgery. CONCLUSIONS: This study establishes the incidence of PVR, and its time of onset, but it was not effective to identify clinical risk factors with a high level of confidence.

Adolescent↗
PubMed2003

[Retinal shortening: the most severe form of proliferative vitreoretinopathy (PVR)].

PURPOSE: To identify the clinical characteristics of patients developing retinal shortening due to intraretinal PVR. METHODS: Observational and retrospective cohort study on 110 PVR patients operated on between 2000 and 2001. During surgery, after removing epiretinal membranes and ruling out the presence of subretinal membranes, a perfluorocarbon liquid was injected. Those cases in which retinal flattening was not accomplished, were considered intraretinal PVR (group 1). Those in which retinal flattening allowed endolaser application, were taken as the control group (group 2). Clinical features of both groups were compared by chi-square test. RESULTS: 60 cases (54.5%, CI 95%: 40.5-68.5) showed retinal shortening (group 1). In 24 cases (21.8%, CI 95%: 12.9-30.7) complete retinal flattening was accomplished (group 2). In 26 cases (23.6%), evaluation was inconclusive. In 9 out of the 60 cases of group 1 (15%) a retinectomy was necessary to reattach the retina. Differences between both groups were not statistically significant for any of the clinical variables. However, the number of retinal detachments of more than 60 days of evolution was significantly higher in retinectomized eyes (20.7%) than in group 1 (3.7%) (p=0.04). CONCLUSIONS: Retinal shortening is a relatively frequent phenomenon in PVR. Further studies are necessary to characterize this clinical presentation of PVR and its pathogenesis.

Case-Control Studies↗
PubMed2002

[Glutathione-related enzymes activity during vitrectomy. Effect of BSS Plus(R) in retinal tissue].

PURPOSE: To determine changes in the retinal activity of two enzymes related to the glutathione metabolism (Glutathione synthetase -GSHS- and glutathione reductase -GSSGR-) after vitrectomy using BSS Plus(R). MATERIAL AND METHODS: Forty-five pigmented rabbits were distributed in 6 groups: group I (GSHS control in retinal tissue); Group II (analysis of GSHS at 3 hours post-vitrectomy); Group III (determination of GSHS at 48 hours after vitrectomy); Group IV (GSSGR control in retinal tissue); Group V (measurement of GSSGR at 3 hours post-surgery) and Group VI (study of GSSGR at 48 hours post-vitrectomy). Statistical analysis was done by a parametric test (ANOVA of single factor) (p<0.05). RESULTS: The activity of these enzymes was: Group I (n=5, basal GSHS). 2785,63 D.S. 419,51 U/g; Group II (n=4, GSHS at 3 hours). 6053,50 D.S. 2788,84 U/g; Group III (n=4, GSHS at 48 hours). 7424,30 D.S. 997,47 U/g; Group IV (n=10, basal GSSGR). 150,86 D.S. 24,40 mU/mL; Group V (n=7, GSSGR at 3 hours). 212,03 D.S. 53,30 mU/mL; Group VI (n=8, GSSGR at 48 hours). 210,84 D.S. 46,03 mU/mL. CONCLUSIONS: At retinal tissue, BSS Plus(R) intraocular irrigating solution increases GSHS activity without modifications of GSSGR levels. It seems to be related to the < > synthesis of glutathione.

Animals↗
PubMed2002

[Ghost cell detection in vitreous cytology: clinico-pathological correlation].

PURPOSE: To determine the prevalence of detection of ghost cells (GCs) in vitreous hemorrhages (VHs) and correlate it with the development of ghost cell glaucoma. To compare our results with those previously reported. METHODS: Retrospective analysis of clinical records and vitreous cytology reports (cytospin and direct paraffin embedding) from patients undergoing vitrectomy for VH at Instituto Universitario de Oftalmobiología Aplicada and University Hospital, Valladolid, for the last 2 years. RESULTS: 76 VHs have been analysed; 45 corresponded to proliferative diabetic retinopathy and the remainder to several pathologies. GCs have been detected in 18 cases (25%) (4 out of 76 specimens were excluded): 14 were phakic and 4 pseudophakic. Most of 76 VHs lasted more than 2 months. No case of ghost cell glaucoma was detected, neither previously nor after vitrectomy. CONCLUSIONS: The frequency of detection of GCs in vitreous cytology may vary according to the cytologic technique. In contrast with the information previously reported, ghost cell glaucoma is an unfrequent disease, particularly after vitrectomy, probably because of a better removal of hemorrhagic debris from the vitreous cavity nowadays. Nevertheless, this diagnosis should not be overlooked.

Aqueous Humor↗
PubMed2001

[Treatment of the massive suprachoroidal hemorrhages].

PURPOSE: To analyze the anatomical and functional results obtained in post- surgical suprachoroidal hemorrhages treated from 1998 to 2000 and to review the information on the series of this complication that have been published during the last five years and which included at least 10 patients. METHODS: A retrospective analysis of the medical records of patients with suprachoroidal hemorrhages at the Instituto Universitario de Oftalmobiología Aplicada (IOBA) - University Hospital of Valladolid. Bibliographic search by Med-Line/Pub Med from 1995 to 2000 was performed. RESULTS: 8 patients who fulfill these criteria have been treated and 8 papers, also complying with the criteria, have been found. CONCLUSIONS: The functional and anatomic results of post-surgical suprachoroidal hemorrhages are still poor, even though the prognosis seems to have improved in the last 20 years. The standardized classification of massive suprachoroidal hemorrhages based on severity and the standardization of the follow-up would improve these results.

Age Factors↗
PubMed2001

[Progressive diffuse subretinal fibrosis syndrome: a case report].

CASE REPORT: The case of a 63 year old woman presenting fibrous subretinal lesions in the posterior pole on a routine ocular fundus check up is reported. The angiographic study showed a choroidal origin window defect next to hypofluorescence areas. The patient did not complain of vision loss or scotomas at any time. DISCUSSION: This clinical picture could be classified as a progressive subretinal fibrosis syndrome with atypical features. However, a differential diagnosis with other choroidal inflammatory conditions should be carried out even though many authors may consider them as different developmental phases of the same entity.

Choroiditis↗
PubMed2001

[Acute macular neuroretinopathy: a case report].

CASE REPORT: A 68 year old woman developed a sudden decrease in her visual acuity in both eyes with several central scotomas. Funduscopy demonstrated a motted alteration of the retinal pigment epithelium in both maculae. The fluorescein angiography showed a choroidal ischemia at the macular level in both eyes. DISCUSSION: The patient was diagnosed of acute macular neuroretinopathy. This entity is included among the so-called < >. However, it is important to determine which of these diseases each patient suffers in order to determine if treatment is necessary, the visual prognosis and the possibility of recurrences.

Acute Disease↗
PubMed2001

[Outer retinal edema or multifocal choroiditis after retinal detachment surgery. A case report].

CASE REPORT: We describe a case of a woman who, in the postoperative period of retinal detachment, developed an ophthalmoscopic picture which could correspond to abnormal outer retinal swelling or multifocal choroiditis. Ophthalmoscopic appearance consists of multiple yellowish subretinal lesions in the temporal area of the posterior pole with a cobblestone appearance. DISCUSSION: The two entities are extremely rare complications of rhegmatogenous retinal detachment surgery, with very similar funduscopic appearance. The first one consists of localized pockets of subretinal fluid remaining after retinal detachment surgery. Multifocal choroiditis is an inflammatory process related to various causes.

Choroiditis↗
PubMed2001

[Flavonoid drugs as antioxidant in intraocular irrigating solution].

PURPOSE: To study the protective effect for vitrectomy of intraocular irrigating solutions containing different concentrations of two antioxidants: Meralop and Activadone and compare them with saline solutions and BSS plus. MATERIAL AND METHODS: Seventy-five pigmented rabbits were divided into 8 groups: I. Control (n=8); II. Gas-vitrectomy (n=15); III. Vitrectomy + saline solution (n=6); IV. Vitrectomy + BSS plus (n=9); V. Vitrectomy + Activadone 90 mg/l (n=8); VI. Vitrectomy + Activadone 180 mg/l (n=9); VII. Vitrectomy + Meralop 16 mg/l (n=10); VIII. Vitrectomy + Meralop 64 mg/l (n=10). Antioxidant activity in lens and retina was measured evaluating the levels of lipoperoxides malondyaldehide (MDA) and 4-hydroxynonenal (4-HNE) by spectrophotometry. RESULTS: MDA + 4-HNE concentrations in lens and retina of each group (mean and standard deviation in nmol/g) were: Group I= 3.806DE1.043, 38.787DE10.404. Group II= 4.353DE3.626, 41.554DE18.520. Group III= 297.306DE103.73, 156.69DE6.82. Group IV= 29.39DE15.38, 112.02DE50.12. Group V= 42.31DE20.82, 55.44DE42.21. Group VI= 27.66DE9.29, 181.061DE79.39. Group VII= 134.93DE133.52, 76.89DE36.02. Group VIII= 112.91DE60.30, 79.97DE38.005. CONCLUSIONS: All intraocular irrigation solutions containing antioxidant substances produced lower MDA + 4-HNE levels than saline solution. In the retina, Activadone 90 mg/l produces less MDA concentration than BSS plus.

Animals↗
PubMed2001

[Inhibition of lipid peroxidation in retinal tissue during vitrectomy. Effect of intraocular irrigating solution BSS plus].

PURPOSE: Several antioxidant substances have been included in intraocular solutions for vitrectomy in order to reduce oxidative stress. The objective of this work is to evaluate the antioxidant effect of BBS plus(R) (with oxidized glutathione) by means of determining scores of Malondialdehyde (MDA) in retinal tissue at different post vitrectomy time-periods. MATERIAL AND METHODS: Thirty pigmented rabbits distributed in three groups (n=10). Group I: Control (no surgery); group II: Vitrectomy adding BSS plus(R), scoring of malondialdehyde at 3 hours post surgery; group III: Vitrectomy adding BBS plus(R), analysis of malondialdehide at 48 hours after vitrectomy. Retinal samples were used to determine the score of malondialdehyde using ion-pairing high performance liquid chromatography. Statistical analysis was performed using ANOVA-Scheffé test (p<0.05). RESULTS: Scores of free MDA (microgram of retinal tissue) were: group I (n=8): 1.080 S.D. 0.389 microgram group II (n=8): 1.273 S.D. 0.710 microgram and group III (n=10): 0.639 S.D. 0.374 microgram. CONCLUSIONS: BSS plus(R) showed antioxidant effects in retinal tissue which were observed better at a later rather than early stage after a vitrectomy.

Animals↗
PubMed2001

[Efficacy of direct paraffin embedding in cytological analysis of vitreous from proliferative vitreo-retinopathy (PVR)].

PURPOSE: To assess the efficacy of direct paraffin embedding in cytological analysis of vitreous samples in patients suffering from PVR, against the commonly used method for this purpose (cytospin). METHOD: Undiluted vitreous or vitreous fluids from 40 subsequent patients with PVR were collected and processed (samples collected from cassette at the end of aspiration line in final stage of vitrectomy process). 40 samples underwent cytospinning, 24 samples were paraffin embedded. Specimens were assessed by an expert ocular pathologist and tested samples were assigned to scoring and non scoring groups (where scoring means at least three cells per field in x60 magnification). RESULTS: All 24 paraffin embedding samples scored according to criteria while 36 of 40 cytospinned samples complied with scoring criteria. Differences were not statistically significant. Macrophages (87.5%) and pigmented cells (85%) were the most frequent findings. CONCLUSIONS: Direct paraffin embedding is useful for cytological studies in vitreous samples of PVR patients.

Humans↗
PubMed2001

[Comparison of different techniques for cytologic analysis of vitreous specimens].

PURPOSE: To assess the efficacy of four methods to study the cytology of vitreous samples, and to evaluate the most efficient for routine analysis and immunocytochemical staining. METHODS: Diluted and undiluted vitreous samples of 87 consecutive patients suffering vitreoretinal surgery for different diseases were analysed. The specimens were centrifugated and then processed through four different procedures: agar sandwich (29 cases), direct paraffin embedding (33 cases), cytospin preparations (82 cases) and cytoblock (8 cases). RESULTS: Evaluable material was obtained in: agar sandwich 18 out of 29 cases (62%), direct paraffin embedding 32 out of 33 cases (96.9%), cytospin 72 out of 82 cases (87.8%) and cytoblock 1 out of 8 cases (12.5%). CONCLUSIONS: Direct paraffin embedding and cytospin are the most efficient procedures for routine purposes. Agar sandwich technique seems to be useful for studying small pieces of tissue. Direct paraffin embedding and agar sandwich technique seems to be valuable for immunocytochemistry. After 8 cases processed with cytoblock, our experience did not show valuable results for processing vitreous samples.

Cytological Techniques↗
PubMed2000

Pharmacokinetics of 0.5 mg of a single and a multiple dose of intravitreal vancomycin in infected rabbit eyes.

The purpose of this study was to determine the pharmacokinetics governing distribution and elimination of 0.5 mg of intravitreal vancomycin in a single dose and in a multiple therapeutic regime in infected rabbit eyes. A total of 96 rabbits was injected with approximately 200 CFU of S. aureus intravitreally. Four days later, a single dose of 0.5 mg of vancomycin was administered to Group I (n=36). Group II (n=60) was injected with a maximum of 4 doses of 0.5 mg every 36 hr. Four animals were sacrificed at different time points in each group. Samples of vitreous, aqueous and blood were taken from each animal for analyses by HPLC. These results were evaluated using the RSTRIP program. High vancomycin concentrations were demonstrated in the vitreous of Group I, with a calculated half-life of 12 hr. In Group II, vancomycin levels were within the therapeutic range during the entire experiment. There was minimal accumulation of the drug, and the half-life did not seem to be longer with multiple doses. In conclusion, the pharmacokinetics do not change significantly when a multidose regime is used compared with a single dose. Therapeutic intravitreal concentrations of vancomycin can be achieved by using repeated doses of 0.5 mg of vancomycin.

Animals↗
PubMed1998

Pharmacokinetics of intravitreal vancomycin in normal and infected rabbit eyes.

The purpose of this study was to determine the pharmacokinetics governing the distribution and elimination of intravitreally injected vancomycin in normal and infected rabbit eyes. Two groups each of 36 pigmented animals were used. Group 1 served as control. In Group 2, experimental endophthalmitis was induced in the right vitreous by inoculation with Staphylococcus aureus. Once endophthalmitis developed, a vancomycin solution was injected. Four animals from each group were killed at nine time points post-injection, the vitreous and aqueous were removed, and blood samples were taken for HPLC analysis. Data analysis was performed using the RSTRIP program. The half-lives were 69 hours in normal vitreous and 14.53 hours in infected vitreous. Therapeutic drug levels were present in the vitreous 84 hours post-injection in all eyes; they were detected from 2 to 48 hours in normal aqueous but at lower levels in the infected ones. Kv and Ca/Cv ratios suggested that the primary route of elimination was across the retina and the anterior chamber in normal eyes, and via the retina in infected eyes. Results indicate that pharmacokinetic parameters change in pathological conditions, which may help establish better treatment guidelines for endophthalmitis.

Animals↗