Biomedical subjects

J Garcia-Sanchez

Publications and source records attributed to J Garcia-Sanchez.

12 recordsLinked to original sources

PubMed2001

Laser in situ keratomileusis enhancement after photorefractive keratectomy.

OBJECTIVE: To describe the safety, effectiveness, and predictability of laser in situ keratomileusis (LASIK) for correcting residual myopia after primary photorefractive keratectomy (PRK). DESIGN: A retrospective, noncomparative case series. PARTICIPANTS AND INTERVENTION: Thirty-six consecutive eyes of 30 patients underwent LASIK after primary PRK. A Multiscan Schwind excimer laser was used for LASIK enhancement. MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity, refraction, videokeratography, and complications were determined before and after LASIK retreatment. Follow-up was at least 12 months. RESULTS: Before LASIK, 11.11% of eyes showed a UCVA of 20/40 or better. This increased to 94.44% 12 months after LASIK. A UCVA of 20/25 or better was achieved in 0% before and in 72.22% after retreatment. Refraction +/-0.5 diopters (spherical equivalent) represented 0% of eyes before and 77.78% of eyes after enhancement. Before LASIK, two eyes had significant haze. Haze remained in these two eyes and appeared in another eye. CONCLUSIONS: Laser in situ keratomileusis proved to be safe and effective for treating residual myopia after PRK. Care must be taken when considering LASIK retreatment in patients with significant haze after primary PRK.

Adult↗

PubMed2001

Decrease in tear secretion and corneal sensitivity after laser in situ keratomileusis.

PURPOSE: To evaluate tear secretion and corneal sensitivity after laser in situ keratomileusis (LASIK) for the correction of myopia. METHODS: In a prospective study, 48 consecutive eyes (24 patients) underwent LASIK to correct myopia ranging from -3.5 to -12.25 diopters. Tear secretion tested by the tear function index and corneal sensitivity tested using the Cochet-Bonnet esthesiometer were evaluated preoperatively and 1 week and 1, 3, 6, and 9 months postoperatively. RESULTS: Tear secretion and corneal sensitivity after LASIK were reduced during the first 3 months after surgery (p<0.001). Tear secretion returned to its preoperative values only after 9 months. Tear secretion and corneal sensitivity were more depressed in long-term contact lens wearers preoperatively and 6 months after surgery (p<0.05). CONCLUSION: In the correction of myopia, tear secretion was depressed after LASIK during the first 6 months after surgery.

Adult↗

PubMed2000

Sulfasalazine in the prevention of anterior uveitis associated with ankylosing spondylitis.

PURPOSE: To assess the effects of sulfasalazine in preventing recurrences and reducing the severity of anterior uveitis associated with ankylosing spondylitis and chronic intestinal inflammation. METHODS: Twenty-two patients with anterior uveitis associated with ankylosing spondylitis were studied. Ten patients were randomised to receive oral sulfasalazine (group 1) and 12 patients randomised to no treatment (group 2); all were followed for 3 years. Blood-aqueous barrier permeability was determined by fluorophotometry and bowel biopsies were taken. RESULTS: A statistically significant difference was observed between the two groups regarding the number of recurrences of uveitis (p = 0.016). The blood-aqueous barrier permeability was significantly higher during acute attacks in group 2 (group 1: 31.3 +/- 26.4 x 10(-4) min-1 vs group 2: 66.2 +/- 28.5 x 10(-4) min-1; p = 0.019) but not during the disease-free period. We observed a higher incidence of chronic intestinal inflammation at the end of the study in group 2 (group 1: 3/8 vs group 2: 7/9, p = 0.153). No relation was observed between blood-aqueous barrier permeability and the number of recurrences. The number of patients with severe persistent posterior synechiae at the end of the study was higher in group 2 (group 1: 4 patients before and 4 patients at the end; group 2: 4 patients before and 8 patients at the end; p = 0.65). CONCLUSION: Sulfasalazine may be beneficial in preventing recurrences and reducing the severity of anterior uveitis associated with ankylosing spondylitis.

Adult↗

PubMed1997

Orbital cup. A device to facilitate ultrasound biomicroscopic examination of pars plana and peripheral retina.

Ultrasound biomicroscopy is a useful technique for anterior segment evaluation; however, examination of the pars plana and the peripheral retina is difficult. We describe a method that facilitates ultrasound biomicroscopic examination of these areas using using a modified swimming goggle(orbital cup) and an eyelid speculum. With this method, not only the pars plana but also structures up to 15 mm from the temporal limbus can be readily imaged.

Anterior Eye Segment↗

PubMed1997

Effects of estrogen use on lens transmittance in postmenopausal women.

OBJECTIVE: Lens autofluorescence originates from an accumulation of fluorescent substances that are associated with the process of cataractogenesis and lens aging. The aim of this study was to determine whether postmenopausal estrogen use reduces age-related nuclear sclerosis in women. DESIGN: The authors designed a case-controlled study. PARTICIPANTS: Nineteen postmenopausal women reporting estrogen use for more than 4 years (group 1), 20 postmenopausal women reporting no estrogen use (group 2), and 23 age-matched men (group 3) were studied. INTERVENTION: The authors performed fluorophotometry. MAIN OUTCOME MEASURES: Corneal and lens autofluorescence and lens transmittance were measured. RESULTS: Lens transmittance values were 0.905 +/- 0.03, 0.839 +/- 0.08, and 0.841 +/- 0.08 in the three groups, respectively. There was a statistically significant difference between group 1 and the other two groups (P < 0.01). CONCLUSIONS: These data are suggestive of a protective effect of estrogen use on the lenses of postmenopausal women.

Aging↗

PubMed1997

Deposits of topical norfloxacin in the treatment of bacterial keratitis.

PURPOSE: Fluoroquinolone solutions are widely used in therapy of bacterial keratitis. These drugs are safe, and their ocular side effects are mild and not serious in nature. The most frequent untoward effect associated with ciprofloxacin therapy has been a white crystalline deposit. This deposit has not been reported after using the other commercially available quinolones, ofloxacin and norfloxacin. METHODS: We present three cases of norfloxacin deposits after treatment of bacterial keratitis. RESULTS: In the three cases, the norfloxacin was substituted for another antibiotic effective against the bacteria, and the precipitate spontaneously resolved in all cases within a few days with no untoward ocular effect. CONCLUSION: Crystalline corneal deposits can develop during topical norfloxacin therapy. The exact factors contributing to the formation are unknown, although the differences in the tear pH/solubility could be involved. Clinicians should be aware of this ocular side effect.

Aged↗

PubMed1996

Analysis of the blood-retinal barrier: its relation to clinical and metabolic factors and progression to retinopathy in juvenile diabetics. A 4-year follow-up study.

BACKGROUND: The study was carried out to evaluate the correlation between blood-retinal barrier (BRB) permeability and the development of diabetic retinopathy (DR) and to assess the metabolic and clinical factors related to DR over a 4-year period by means of vitreous fluorophotometry (VF). METHODS: Thirty-five type I diabetics with no retinopathy, age 7-21 years (mean 14.32 +/- 2.1 years) were enrolled in this longitudinal study. Two visits included standard ophthalmological examination, fluorescein angiography and VF were performed, on entry into the study and 4 years later. The following risk factors in DR were analyzed: age, duration of diabetes, blood pressure, cholesterol, triglycerides, fasting blood glucose levels, glycosylated hemoglobin (HbA1c), insulin dose/kg body weight (IDBW), fructosamine and albuminuria. To estimate the BRB permeability we adopted the vitreous penetration ratio transmittance (VPRt) value. RESULTS: At 4-year follow-up the mean VPRt had significantly increased. During that time 13 patients developed DR and their final mean VPRt was significantly higher than that in non-DR patients. Additionally, the initial mean VPRt was higher but not significantly so, in patients that later developed DR than in non-DR subjects. A constant linear correlation was found between VPRt and duration of diabetes, HbA1c and microalbuminuria. CONCLUSION: VF is a quantitative method that could measure and predict the breakdown of the BRB before angiographic retinopathy in type I diabetics. The major clinical and metabolic factors related to alterations in the BRB are duration of diabetes, HbA1c and microalbuminuria.

Adolescent↗

PubMed1996

Ultrasound biomicroscopy in pars planitis.

PURPOSE: To report the diagnosis of pars planitis on the basis of ultrasound biomicroscopy images. METHODS: The Humphrey ultrasound biomicroscope was used for examination of the right eye of a 17-year-old boy, referred to our clinic because of blurred vision. The lens showed a posterior subcapsular cataract precluding fundus visualization. RESULTS: Ultrasound biomicroscopy showed a homogeneous mass of medium reflectivity over the pars plana. Lensectomy and vitrectomy confirmed the diagnosis. CONCLUSION: This brief case report points out the utility of ultrasound biomicroscopy in diagnosing pars planitis in cases of media opacities.

Adolescent↗

PubMed1994

Effect of bendazac lysine on lens and retina in diabetics.

The possible beneficial effects on the lens and retina which Bendazac Lysine may have in the treatment of adult diabetic patients were investigated. Twenty patients, ranging in age from 54.80 +/- 5.86 years old, were studied. The average duration of the diabetes was 11.32 +/- 4.10 years. Thirteen patients had background retinopathy. The metabolic controls carried out during the study were satisfactory (HbA1 < 11%). Bendazac Lysine (500 mg three times a day) was administered for 6 months. Blood-retinal barrier permeability (VPR and VPRt) and lens transmittance (t) were evaluated prior to and 6 months after treatment by fluorophotometry. No statistically significant differences between the pre- and post-treatment values of the retina permeability were observed, however, there was a statistically significant improvement (p < 0.05) (initial value: t = 0.813 +/- 0.040 and final value: t = 0.823 +/- 0.037) in the lens transmittance. The authors conclude that Bendazac Lysine has a beneficial effect on the lens in the diabetic adult although no improvement in the permeability of the blood-retinal barrier has been observed.

Administration, Oral↗

PubMed1994

Immunohistochemical study of human retinal astroglia.

Immunocytochemical localization of glial fibrillary acidic protein (GFAP) has been used to study astrocyte distribution and morphology in whole mounted human retinas and vertical sections. Two types of astrocytes can be distinguished: elongated astrocytes are located in the nerve fibre layer (NFL); and star-shaped astrocytes are found in the ganglion cell layer (GCL). Astroglial processes join to form bundles. The bundles formed by the elongated astrocytes lie along and separate the nerve fibre bundles. Processes from star-shaped astrocytes reach towards other star-shaped astrocytes and towards the vessels to form a morphologically honeycombed plexus. These astrocytes also send other processes towards the internal nuclear layer (INL), forming an irregular plexus which accompanies the GCL capillaries that extend into the INL. Often, the cell bodies of the star-shaped GCL astrocytes lie over vessels and form cell clusters. Finally, none of the retinas examined for this study evidenced the "perivascular astrocytes" described by Wolter in the human retina.

Adult↗

PubMedDate not supplied

Corneal endothelial permeability after implantation of angle-fitted anterior chamber lenses in myopic phakic eyes. Preliminary results.

This present study aimed to evaluate the corneal endothelium after implantation of angle-fixed anterior chamber lenses in myopic phakic eyes. Twelve eyes (9 patients) with high myopia (more than-14 diopters) were implanted with ZB5M lenses (Domilens, France). The corneal endothelium was studied by fluorophotometry (endothelial transfer coefficient: kc.ca), specular microscopy and ultrasonic pachimetry. Tests were performed prior to and 3 and 6 months after the surgery. The Wilcoxon rank test was used for the statistical analysis of the data. There was a significant difference (p < 0.05) between the preoperative kc.ca (4.15 +/- 0.72 x 10(-3) min-1) and the kc.ca three months after the implantation (4.43 +/- 0.87 x 10(-3) min-1). A statistically significant difference (p < 0.01) was also found between the three and six months postoperative kc.ca (5.31 +/- 0.81 x 10(-3) min-1). There was a significant difference (p < 0.05) between the preoperative central endothelial cell density (2533 +/- 219 cells/mm2). No significant differences were found in relation to the central corneal thickness. In conclusion, three months after the implantation of ZB5M lenses to correct high myopia in phakic eyes, the corneal endothelial function was altered and continued to be so six months after the operation.

Adult↗

PubMedDate not supplied

Effect of topical cyclosporin A on Thygeson's superficial punctate keratitis.

Thygeson's superficial punctate keratitis (Thygeson's SPK) is a distinct clinical entity, characterized by round conglomerates of discrete, granular, white-gray, fine intraepithelial dots without conjunctival involvement. The only effective treatment with regard to relieving symptoms and diminishing lesions has been topical corticosteroids, but their prolonged use can be associated with severe side-effects. The purpose of this study is to present the long-term results of the use of 2% topical cyclosporin A in olive oil in Thygeson's SPK. Eight patients diagnosed as having Thygeson's SPK were included. All the patients were treated with 2% cyclosporin dissolved in olive oil four times a day for three months, and two times a day for one month before withdrawing therapy. The follow-up period ranged from twelve to twenty-five months. The number of corneal lesions varied between 5 and 15 before treatment. After cyclosporin treatment, no corneal lesion was observed and the cornea remained clear after the follow-up period. In conclusion, 2% cyclosporin in olive oil is a safe alternative to corticosteroids in the treatment of Thygeson's SPK, and resulted in satisfactory control of the condition.

Administration, Topical↗