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Biomedical subjects

A Azuara-Blanco

Publications and source records attributed to A Azuara-Blanco.

At least 55 records · Page 3Linked to original sources
PubMed1998

Non-Acanthamoeba amebic keratitis.

PURPOSE: To describe the clinical presentation and outcome of two cases with presumed non-Acanthamoeba amebic keratitis. METHODS: Case reports. RESULTS: Both patients presented with typical symptoms and signs of Acanthamoeba keratitis. The patients' soft contact lenses, lens cases, open solutions, and conjunctival samples were cultured. Diagnosis of non-Acanthamoeba amebic keratitis was based on the presence of keratitis and amebic growth from patients' contact lenses of the affected eyes. Amebic culture from the contralateral contact lens was negative. Vahlkampfia cysts were identified in case 1, and Naegleria cysts in case 2. Topical treatment with polyhexamethylene biguanide and propamidine resolved the keratitis in case 1. Case 2 was lost to follow-up. CONCLUSION: Non-Acanthamoeba amebic keratitis was diagnosed in two patients based on the clinical presentation (resembling Acanthamoeba keratitis), culture of the contact lens, and response to antiamebic treatment (in one case). Keratitis associated with Naegleria contamination of contact lenses has not been previously reported.

Adolescent↗
PubMed1998

Tono-Pen determination of intraocular pressure in patients with band keratopathy or glued cornea.

AIMS: To evaluate the intraocular pressure (IOP) measurements in patients with band keratopathy or glued corneas obtained from affected and non-affected areas. METHODS: 15 patients with band keratopathy or glued corneas were prospectively recruited. When both eyes were affected, only the right eye was analysed. Tono-Pen readings of IOP were obtained sequentially from the affected and non-affected corneal surface. Additionally, Goldmann applanation tonometry was attempted. RESULTS: Determination of IOP with the Tono-Pen was possible in all cases, while Goldmann tonometry was not performed in three patients because of severe corneal irregularities. The average of the Tono-Pen readings obtained from the affected cornea (34.8 (SD 14.0) mm Hg) was consistently and significantly higher (p < 0.001) than mean IOP obtained by the Tono-Pen from the non-affected area (14.8 (4.3) mm Hg). The average of Goldmann tonometry readings (14.4 (6.1) mm Hg) did not differ significantly from the Tono-Pen values obtained from the non-affected corneal area (p = 0.47) but was significantly lower than the Tono-Pen measurements obtained from the affected area (p < 0.001). CONCLUSION: In patients with band keratopathy or glued corneas determination of IOP by Tono-Pen tonometry varies from affected to non-affected area. The Tono-Pen overestimates the level of IOP when it is applied to areas with band keratopathy or with glue.

Corneal Diseases↗
PubMed1998

Effects of short term increase of intraocular pressure on optic disc cupping.

AIMS: To evaluate the effect of acute elevation of intraocular pressure (IOP) on optic disc cupping. METHODS: 10 emmetropic and 10 myopic volunteers were included in this study. The cup area (CA) and cup volume (CV) of the optic disc were determined with the Heidelberg retina tomograph (HRT). After baseline determinations, a suction cup was used to increase the intraocular pressure (IOP) to 20-25 mm Hg above the baseline and HRT images were obtained. RESULTS: Baseline IOP was 13.5 (SD 1.3) nim Hg and 12.6 (2.6) mm Hg in the emmetropic and myopic groups, respectively. The IOP was elevated to 35.4 (3.3) mm Hg and 34.4 (2.5) mm Hg in the emmetropic and myopic groups, respectively. When compared with their baseline values, the cupping variables (CA and CV) were significantly increased (p < 0.05) during the suction treatment in both emmetropic and myopic subjects. CONCLUSION: There was a significant enlargement in the optic disc cupping during the artificial increment of intraocular pressure in both emmetropic and myopic eyes. In non-glaucomatous eyes the optic nerve head has a partially dynamic topography dependent upon the level of IOP.

Adult↗
PubMed1998

Reproducibility of optic disk topographic measurements with the Topcon ImageNet and the Heidelberg Retina Tomograph.

OBJECTIVE: To compare the reproducibility of optic disk measurements provided by an image analyzer and a scanning laser tomograph. METHODS: Ten images of the same eye of 10 normal volunteers were taken with the Heidelberg Retina Tomograph and with the Topcon ImageNet. Intraclass correlation coefficient (ICC) and coefficient of variation (CV) were used to evaluate the reproducibility of the measurements. RESULTS: Eleven parameters were analyzed with the Topcon ImageNet. Six parameters (55%) had ICC greater than 90%. Four parameters (36%) had CV less than 10%. Twelve parameters were evaluated with the Heidelberg Retina Tomograph. Nine parameters (75%) had ICC over 90%. Nine parameters (75%) had CV less than 10%. CONCLUSION: Both systems provided reproducible data. The optic disk parameters provided by the Heidelberg Retina Tomograph had a better reproducibility than those obtained from the Topcon ImageNet.

Adult↗
PubMed1998

Evaluation of contamination of used disposable contact lenses by Acanthamoeba.

PURPOSE: The purpose of this study was to evaluate the contamination of used disposable soft contact lenses with Acanthamoeba. METHODS: We evaluated 51 consecutive disposable soft contact lens wearers in a prospective study. Before their check-up visits, patients were offered a free new contact lens in exchange for donating their old one. The used contact lenses (n = 102) were then removed and placed in culture medium for Acanthamoeba. We subsequently investigated patterns of wear and hygiene habits. RESULTS: The mean age of this population was 32.6 +/- 11.0 years. The average time of disposable soft contact lens wear was 13.7 hours per day. The contact lenses were disinfected daily with commercial solutions. Twenty-five (49.0%) subjects did not clean their lens cases properly. Acanthamoeba was not isolated from any of the 102 lenses. CONCLUSIONS: There were no cases of Acanthamoeba contamination in a small population of disposable soft contact lens wearers who regularly disinfected their lenses with standard commercially available contact lens solutions.

Acanthamoeba↗
PubMed1997

Ultrasound biomicroscopy in infantile glaucoma.

BACKGROUND: Glaucoma in infants has many causes: Evaluation of the anatomy of the anterior segment of eyes with infantile glaucoma may help to determine the pathogenesis of an infant's disease and influence therapeutic decisions. METHODS: Eleven eyes of six infants with glaucoma were evaluated with ultrasound biomicroscopy (UBM) to evaluate the anatomic characteristics and relationships of the anterior segment structures. RESULTS: The anterior chamber angle, iris, lens, ciliary body, and posterior chamber angle could be imaged in detail. Elongated and anteriorly placed ciliary processes were noted in all eight eyes with trabeculodysgenesis. There were no apparent anomalies in the trabecular meshwork, or anterior chamber. In three eyes with dense corneal opacities, ultrasound biomicroscopy showed severe anterior segment disorganization and thin central corneas with posterior corneal excavation. CONCLUSIONS: Ultrasound biomicroscopy is a useful non-invasive method for evaluating infants with glaucoma in cases with corneal opacities. This information can help in surgical planning for glaucoma management.

Anterior Eye Segment↗
PubMed1997

Mitomycin-C supplemented trabeculectomy, phacoemulsification, and foldable lens implantation.

PURPOSE: To evaluate the outcome of combined mitomycin-C filtering surgery, phacoemulsification, and foldable intraocular lens (IOL) implantation. SETTING: Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania, USA. METHODS: This retrospective study evaluated 182 eyes of 174 patients who had combined mitomycin-C trabeculectomy, phacoemulsification, and insertion of a foldable IOL through a 3.5 mm incision. Success of the combined procedure was defined as intraocular pressure (IOP) below 21 mm Hg, with or without medications, and no serious complication. Success rates were calculated using the Kaplan-Meier actuarial method. RESULTS: Mean follow-up was 16.7 months +/- 5.4 (SD). The probability of success at 6, 12, 18, and 24 months was 98.3, 95.6, 90.6, and 88.0%, respectively. When compared with preoperatively, visual acuity improved one or more lines in 148 eyes (81.3%) and worsened one or more lines in 15 (8.2%); 111 eyes (61.0%) achieved visual acuity of 20/40 or better. The most frequent complication was posterior capsule opacification requiring capsulotomy, which occurred in 22 cases (12.0%). CONCLUSION: The 1 year and 2 year IOP control rate of combined mitomycin-C filtering procedures and phacoemulsification in glaucoma patients was high.

Aged↗
PubMed1997

Methods to objectify reversibility of glaucomatous cupping.

Lowering intraocular pressure in adults with glaucoma may be associated with an improvement in appearance of the optic nerve head. The stage of disease, the amount of intraocular pressure reduction, and the age of the patient probably influence the occurrence of this event. The clinical relevance of "reversal" has not been established with certainty. The reversibility of glaucomatous cupping can be detected by subjective and qualitative means (examination of the patient or of fundus photographs) or by quantitative techniques such as photogrammetry, computerized image analysis, and scanning laser tomography. Clinical and experimental studies are providing new information about the behavior of the optic nerve head tissues in response to changes in intraocular pressure.

Adult↗
PubMed1997

Intraobserver and interobserver agreement in evaluating the anterior chamber angle configuration by ultrasound biomicroscopy.

PURPOSE: To determine the intra- and interobserver agreement in assessing the configuration of the human anterior chamber angle using ultrasound biomicroscopy (UBM). METHODS: Two masked clinicians used ubm images to estimate, in 41 eyes, (a) the position of contact between the peripheral iris and the inside of the eye wall, (b) the angular size of the anterior chamber angle (ACA), and (c) the curvature of the peripheral iris. Both observers, masked to the previous results, examined the same images in a second session. Agreement was evaluated using the unweighted kappa statistic. RESULTS: Intraobserver agreement in assessing the iris insertion, angular width, and the iris curvature was high (range of kappa values, 0.83-0.92). Interobserver agreement in evaluating the level of iris insertion (kappa = 0.79), the angular width (kappa = 0.95), and the iris curvature (kappa = 0.84) was also high. CONCLUSION: The agreement within the same observer and between observers in evaluating the ACA configuration by UBM was excellent.

Anterior Chamber↗
PubMed1997

Familial exudative vitreoretinopathy associated with nonneovascular chronic angle-closure glaucoma.

PURPOSE: Cases of angle-closure glaucoma in patients with familial exudative vitreoretinopathy have been reported secondary to neovascularization of the anterior segment. Cases secondary to nonneovascular mechanisms have not been previously reported. METHODS: Two cases are presented of angle-closure glaucoma as a result of a nonneovascular mechanism. RESULTS: Neovascularization was found to be a very unlikely explanation for the angle closure in these two cases. CONCLUSION: There may be an association between familial exudative vitreoretinopathy and angle-closure glaucoma as a direct result of a retrolental process or more likely a relative lens-iris pupillary block with a large lens.

Anterior Eye Segment↗
PubMed1997

Severe visual loss after autologous blood injection for mitomycin-C-associated hypotonous maculopathy.

It has been shown that mitomycin-C increases the success rate of trabeculectomy; however, a rise in the incidence of postoperative complications has also been reported. Consequently, the use of antimetabolite is usually reserved for patients who are at high risk of surgical failure or for patients with advanced glaucoma in whom low intraocular pressure is desired. This report describes a patient who suffered severe visual loss which was a direct result of hypotonous maculopathy after trabeculectomy with mitomycin-C and various other complications from the subsequent interventions.

Adult↗
PubMed1997

Infectious keratitis in a paracentesis tract.

A paracentesis is performed in glaucoma procedures as a flat, beveled tract to allow access into the anterior chamber after the filtration fistula is made. Complications related to the paracentesis are infrequent because it is a self-sealing wound. The authors report a case of infectious keratitis that developed in a paracentesis tract.

Abscess↗
PubMed1997

Quantitative estimation of retinal nerve fiber layer height in glaucoma and the relationship with optic nerve head topography and visual field.

PURPOSE: The authors estimated the retinal nerve fiber layer height (RNFLH) measurements in patients with glaucoma compared with those in age-matched healthy subjects as obtained by the laser scanning tomography and assessed the relationship between RNFLH measurements and optic and visual field status. METHODS: Parameters of optic nerve head topography and RNFLH were evaluated in 125 eyes of 21 healthy subjects and 104 patients with glaucoma using the Heidelberg Retina Tomograph ([HRT] Heidelberg Engineering GmbH, Heidelberg, Germany) for the entire disc area and for the superior 70 degrees (50 degrees temporal and 20 degrees nasal to the vertical midline) and inferior 70 degrees sectors of the optic disc. The mean deviation of the visual field, as determined by the Humphrey program 24-2 (Humphrey Instruments, Inc., San Leonardo, CA, U.S.A) was calculated in the entire field and in the superior and inferior Bjerrum area. RESULT: Retinal nerve fiber layer height parameters (mean RNFLH and RNFL cross-sectional area) were decreased significantly in patients with glaucoma compared with healthy individuals. Retinal nerve fiber layer height parameters was correlated strongly with rim volume, rim area, and cup/disc area ratio. Of the various topography measures, retinal nerve fiber layer (RNFL) parameters and cup/disc area ratio showed the strongest correlation with visual field mean deviation in patients with glaucoma. CONCLUSION: Retinal nerve fiber layer height measures were reduced substantially in patients with glaucoma compared with age-matched healthy subjects. Retinal nerve fiber layer height was correlated strongly with topographic optic disc parameters and visual field changes in patients with glaucoma.

Female↗