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At least 1,333 records · Page 74Linked to original sources
PubMed1998

Beneficial effects of 1-year captopril therapy in children with chronic aortic regurgitation who have no symptoms.

OBJECTIVE: This prospective study was performed to assess the effects of 1 year of angiotensin-converting enzyme inhibition with captopril in 20 children (mean age 14.3+/-2.3 years) with asymptomatic chronic aortic regurgitation. METHODS AND RESULTS: At 12 months patients receiving captopril had a significant reduction in left ventricular end-diastolic and end-systolic dimensions (57+/-9.3 vs 51+/-9.5 mm, p < 0.001; 35.4+/-6.1 vs 32+/-6.8 mm, p < 0.001), end-diastolic and end-systolic volume indexes (111+/-36 vs 94+/-29 ml/m2, p < 0.001; 35+/-13 vs 30+/-12 ml/m2, p < 0.001, respectively), and mass index (138+/-37 vs 109+/-32 gm/m2, p < 0.0001) determined by two-dimensional echocardiography. Meridian (p < 0.01) and circumferential (p < 0.0001) wall stresses also decreased significantly with therapy. Significant reduction (27.8%, p < 0.0001) was achieved in regurgitant fraction with captopril. CONCLUSIONS: These data show that the long-term therapy with angiotensin-converting enzyme inhibitors is able to reverse left ventricular dilation and hypertrophy and suggest that such therapy has the potential to favorably influence the natural history of the disease in children.

Administration, Oral↗
PubMed2001

Peripheral homonymous scotomas from a cavernous angioma affecting fibers subserving the intermediate region of the striate cortex.

PURPOSE: To report the case of a pure peripheral homonymous visual field defect and to delineate the representation of the visual field on the striate cortex. METHODS: Observational case report. Neuro-ophthalmologic and neuroimaging assessment of a patient with a cavernous angioma of the right parieto-occipital lobe. RESULTS: The patient had left homonymous scotomas located 40 degrees to 60 degrees from the vertical meridian. Neuroimaging indicated that the lesion was affecting the optic radiations at their termination in the intermediate portion of the striate cortex or the striate cortex itself. CONCLUSION: Homonymous field defects are typically located within 10 degrees of fixation. This patient had a peripheral homonymous field defect from damage to the intermediate striate cortex. Correlation of the neuroimaging findings in this case with the most commonly used maps of the representation of the visual field on the striate cortex suggests that none of the maps correctly predicts the location or extent of lesions that affect the intermediate portion of the cortex.

Adult↗
PubMed2001

Evaluation of the peripheral visual field after foveal translocation.

PURPOSE: To evaluate the peripheral visual field after foveal translocation with scleral imbrication or 360-degree retinotomy. METHODS: Retrospective, single-center, nonrandomized study. We calculated the rate of preservation of the peripheral visual field using Goldmann perimetry by dividing the width of the postoperative V-4 isopter by the preoperative width and expressing the result as a percentage. RESULTS: In nine eyes that underwent scleral imbrication, the rate of preservation was 100.0% superiorly, 102.6% superotemporally, 99.9% temporally, 97.9% inferotemporally, 96.9% inferiorly, 82.3% inferonasally, 93.7% nasally, and 87.3% superonasally. In 33 eyes that underwent 360-degree retinotomy, it was 89.1%, 87.0%, 81.9%, 78.1%, 86.6%, 90.0%, 89.9%, and 86.8%, respectively. CONCLUSION: After foveal translocation with scleral imbrication, the peripheral visual field was preserved except for slight narrowing nasally; 360-degree retinotomy resulted in preservation of the visual field, except for slight narrowing in all meridians.

Aged↗
PubMed2001

Vitreous hemorrhage from a ciliary granuloma associated with Wegener granulomatosis.

PURPOSE: To report a case of vitreous hemorrhage from ciliary granuloma in Wegener granulomatosis. METHODS: Interventional case report. An 18-year-old woman with Wegener granulomatosis and episcleral granuloma in her LE had ultrasound biomicroscopy findings of a mass in the pars plana of the ciliary body in the meridian corresponding to the episcleral granuloma. RESULTS: The patient underwent vitrectomy in the LE for subsequent vitreous hemorrhage. Intraoperatively, the mass was diagnosed as a ciliary granuloma at the pars plana. Dense blood clotting around the ciliary granuloma and subretinal exudation at the ora serrata were observed, with no other changes causative for the vitreous hemorrhage. CONCLUSIONS: We report a case of vitreous hemorrhage associated with a ciliary granuloma that was revealed by ultrasound biomicroscopy. Careful observation is necessary in eyes with persistent inflammation in Wegener granulomatosis.

Adolescent↗
PubMed2003

Foveal hypoplasia demonstrated in vivo with optical coherence tomography.

PURPOSE: We demonstrate foveal hypoplasia by optical coherence tomography (OCT). DESIGN: Observational case report. METHODS: Foveal hypoplasia was demonstrated in a 79-year-old man with decreased vision since childhood using fundus photography, fluorescein angiography, and OCT scans through four meridians of the central foveal. RESULTS: The OCT showed extension of all neurosensory retinal layers through the area in which the fovea would normally be located. CONCLUSION: Optical coherence tomography can be used to demonstrate foveal hypoplasia.

Aged↗
PubMed1996

Occult macular dystrophy.

PURPOSE: Occult macular dystrophy is a hereditary macular dystrophy without any visible abnormality of the fundus or abnormality indicated by fluorescein angiography even when visual acuity is decreased. Normal full-field electroretinogram in both cone and rod components with abnormal focal macular cone electroretinogram is the key to diagnosing this disorder. The purpose of this study was to identify the function of the macular rods and to provide detailed clinical findings in occult macular dystrophy. METHODS: Thirteen patients from eight families were examined. The fundi of 12 patients were essentially normal (occult macular dystrophy), and the oldest patient in one family disclosed bull's eye maculopathy. In the 12 patients, including the patient with bull's eye maculopathy, the profiles of cone and rod absolute thresholds were performed across the 60-degree horizontal meridian of the posterior pole. RESULTS: All 12 patients showed cone sensitivity loss only in the macular area. Six relatively young patients revealed normal rod sensitivity, whereas six older patients showed borderline rod sensitivity or abnormal rod sensitivity in the macular area. CONCLUSIONS: The pathology of occult dystrophy involves either only the macular cone system or macular cone and rod systems without any visible abnormality. This difference of the pathology suggests a different clinical entity or a different stage of occult macular dystrophy.

Adolescent↗
PubMed1996

Retinal pigment epithelial cell count, distribution, and correlations in normal human eyes.

PURPOSE: To determine the number of the retinal pigment epithelial cells, their regional distribution, and correlations with general variables in normal human eyes. METHODS: We examined 53 normal human donor eyes from individuals with a mean age of 58.6 +/- 18.8 years and an axial length of less than 27 mm. After opening the globes by a 16-mm corneoscleral trephination, up to 25 biopsy specimens of the retina and retinal pigment epithelium were obtained in four meridians. The retinal pigment epithelial cells and the retinal photoreceptors were counted on photographs taken from the apical retinal pigment epithelial surface and the inner photoreceptor segments. RESULTS: Total number of the retinal pigment epithelial cells was 3,556,290 +/- 490,700 (mean +/- S.D.; range, 2,130,500 to 4,653,200), and it was positively correlated with the number of rods and cones, the total area of the retina, the optic disk size, and the retinal pigment epithelial cell density but was independent of gender. The retinal pigment epithelial cell density decreased significantly (P < .001) from the fovea (4,220 +/- 727 cells/mm2) to the midperiphery (3,002 +/- 460 cells/mm2) and to the outer peripheral fundus regions (1,600 +/- 411 cells/mm2). In the retinal periphery, the retinal pigment epithelial cell density was the highest (P < .01) in the nasal fundus region compared with any other fundus quadrant. The retinal pigment epithelial cell density decreased by about 0.3% per year with increasing age. CONCLUSIONS: These data on the quantitative anatomy of the retinal pigment epithelium may be important for physiology and pathophysiology of the visual process, especially in evaluating the effects of aging.

Adolescent↗
PubMed1996

Treatment of maculopathy associated with optic disk pit by sponge explant.

PURPOSE: To evaluate the anatomic and functional outcome in nine patients with optic disk pit maculopathy after the use of the macular buckling procedure. METHODS: In this prospective study, nine consecutive patients (five women and four men with a mean age of 28 years [range, 14 to 49 years] who had unilateral maculopathy associated with optic disk pit) were treated with macular buckling surgery. A scleral sponge of 7.5 x 5.5 mm was fixed at the posterior pole of the globe corresponding to the macula along the vertical axis of the 12-to-6 o'clock meridian. No additional treatment of any kind (laser, diathermy, or cryotherapy) was used. The correct positioning of the sponge during the operation was monitored by B-scan ultrasonography. Within the first week after surgery, indocyanine green angiography was performed to evaluate the choroidal circulation. During the same period, magnetic resonance imaging of the orbit was performed to determine the sponge position in relation to the optic nerve. RESULTS: In all nine eyes, complete disappearance of subretinal and intraretinal fluid in the macula and in the surrounding area was noted. The absorption of the macular fluid started immediately after the operation and was completed after five to six months. No further change of the appearance of the fundus was noted during the follow-up period, which ranged from 18 to 66 months (mean follow-up, 42 months). Six eyes gained four or five lines of visual acuity, and two eyes improved by three lines. CONCLUSIONS: The macular scleral buckling procedure in optic disk pit maculopathy can yield favorable anatomic and functional results.

Adolescent↗
PubMed1992

Results of lamellar crescentic resection for pellucid marginal corneal degeneration.

Five eyes in four patients with pellucid marginal corneal degeneration were treated by lamellar crescentic resection of the thinned area inferiorly. Normal-thickness stroma was then reapposed to normal-thickness stroma with multiple interrupted 10-0 polypropylene sutures. If excessive central corneal steepening along a vertical meridian was present three months after surgery, selected sutures were cut and removed depending on the slit-lamp appearance, keratometry reading, and photokeratograph pattern. Improvement of visual acuity to 20/40 or better was obtained in four of the five eyes with a follow-up of 27 to 40 months (mean, 31.8 months). Early loosening of sutures resulted in a recurrence of corneal thinning and astigmatism in one eye. Pannus developed inferiorly in all five eyes.

Adolescent↗
PubMed1996

Increase in iris-lens contact after laser iridotomy for pupillary block angle closure.

PURPOSE: To quantitate changes in anterior ocular segment anatomy after laser iridotomy for pupillary block angle closure. METHODS: We prospectively performed ultrasound biomicroscopy and A-scan biometry in 13 eyes of 13 consecutive untreated patients with relative pupillary block and appositional angle closure, without peripheral anterior synechiae on indentation gonioscopy. A radial, perpendicular image in the horizontal temporal meridian was obtained with ultrasound biomicroscopy before and one week after laser iridotomy in each eye. RESULTS: Mean age of the 13 patients was 69.3 +/- 1.8 (S.E.) years, mean refractive error was +1.37 +/- 0.39 diopters, and mean axial length was 22.54 +/- 0.20 mm. In 13 eyes, before and after laser iridotomy measurements of angle-opening distance (0.11 +/- 0.02 vs. 0.18 +/- 0.02 mm) (P = .0004; paired t test), angle aperture (8.3 +/- 1.3 vs 18.6 +/- 2.8 degrees) (P = .0003) and iris-lens contact distance (0.58 +/- 0.06 vs 1.18 +/- 0.14 mm) (P = .0003) were greater postoperatively, but anterior chamber depth was unchanged (P = .7). CONCLUSIONS: Flattening of the iris after laser iridotomy for pupillary block causes an increase in iris-lens contact. The change in angle configuration after iridotomy results more from an alteration in aqueous pressure gradients across the iris rather than from posterior lens movement.

Aged↗
PubMed1989

Corneal compression sutures for the reduction of astigmatism after penetrating keratoplasty.

We placed interrupted 9-0 nylon sutures across the graft-host interface of ten eyes with more than 5 diopters of keratometric cylinder after penetrating keratoplasty in order to steepen the flattest corneal meridian and reduce the amount of corneal cylinder. Placement of compression sutures reduced corneal cylinder by an average of almost 6 diopters one week later. Average corneal cylinder was 5.1 diopters nine to 12 months after surgery. Best-corrected visual acuity with spectacles improved by an average of two Snellen lines (20/60 to 20/40) and uncorrected visual acuity improved by an average of one line (20/300 to 20/200). There were no complications related to placement of the sutures. This procedure provides a rapid and simple method for reducing astigmatism after penetrating keratoplasty.

Astigmatism↗
PubMed1987

Screening for glaucomatous visual field loss with automated threshold perimetry.

We examined 27 glaucomatous eyes and 154 normal eyes with automated threshold perimetry. Previously suggested algorithms for detecting mild to moderate glaucomatous visual field loss, primarily by comparing the sensitivity of corresponding clusters of points above and below the horizontal meridian, yielded results remarkably consistent with those of our earlier series: 93% (25 of 27) of abnormal and 88% (135 of 154) of normal eyes were correctly identified. Excluding unreliable examinations increased specificity from 88% to 93%. Test duration was similar to results with the Field Analyzer's older, purportedly slower operating system.

Aged↗
PubMed1985

Observations on the retinopathy of prematurity.

The fourfold to fivefold increased survival rate since 1950 of premature infants with birthweights of less than 1,000 g apparently explains the increase in cases of retinopathy of prematurity in recent years. A new international classification permits standardized grading of the retinopathy of prematurity based on severity, anterior-posterior location, and the meridians involved. Previously reported clinical trials on the role of vitamin E in the prevention of retinopathy of prematurity have given conflicting results.

Carbon Dioxide↗
PubMed1994

Treatment of secondary posterior capsular membranes with the Nd:YAG laser in a pediatric population.

Thirty-two eyes of 28 pediatric patients were treated with the H. S. Meridian Microruptor III Nd:YAG laser for secondary posterior capsular membranes after cataract extraction either with or without posterior chamber intraocular lens implantation. This laser allows for 90-degree rotation of the laser delivery system to treat recumbent patients who may be under general endotracheal anesthesia. In all patients, at least a 5-mm axial capsulotomy was created. The energy requirements for the procedure were related to the density of the membrane, which correlated with the time lapse between cataract extraction and laser capsulotomy. A second laser capsulotomy was performed in eight eyes. Nd:YAG capsulotomy can be performed in a child of any age by using the Microruptor III. For surgeons who choose to retain the posterior capsule in pediatric cataract extraction, particularly after posterior chamber intraocular lens implantation, this technique offers the noninvasive capability to create and maintain a clear visual axis.

Adolescent↗
PubMed1990

The effect of iridotomy on iris contour.

With a recently developed technique for quantifying the geometry of the anterior chamber in optical cross section (slit-lamp photography using the Scheimpflug principle and computer correction for the optical effects of the cornea), we studied the iris contour before and after iridotomy in six patients with narrow anterior chamber angles and angle-closure glaucoma. Before iridotomy, the iris contour was convex anteriorly in all meridians. After iridotomy, the anterior lens surface position did not change perceptibly. The iris at the pupil margin settled backward onto the lens surface, no longer held forward by the narrow stream of aqueous passing from the posterior chamber to the anterior chamber. Next to the pupil there was often a perceptible mound, presumably representing the iris sphincter. From the point of support by the lens to the root of the iris, the contour of the iris surface was a straight line, except for the surface irregularities. The deepening of the anterior chamber at each point was the difference between the convex contour before iridotomy and the straight line after iridotomy.

Glaucoma↗
PubMed1983

Adaptation to tilting of the visual environment in cyclotropia.

We evaluated adaptations to tilting of the visual environment in 18 patients with cyclotropia by comparison of subjective tests for torsion with the actual rotation of the globes determined by fundus photography. Patients with congenital cyclotropia had a sensory reorientation of the spatial values of retinal meridians in the cyclotropic eye that prevented awareness of tilting of the environment under uniocular and binocular conditions. Patients with cyclotropia acquired as adults in many instances also had retinal sensory reorientations of the cyclotropic eye or eyes. Additionally, they used spatial clues from the visual environment to correct for image tilting under uniocular conditions. Under dissociated binocular conditions, however, these patients became aware of tilting of the visual environment, and therefore these adaptations were less deeply rooted than those in patients with congenital cyclotropia. Because certain patients with acquired cyclotropia showed evidence of using these adaptations under uniocular conditions but had constant or intermittent torsional diplopia under casual binocular viewing conditions, binocular mechanisms such as cyclofusion, suppression, and anomalous retinal correspondence may also be necessary to eliminate subjective tilting of the visual environment.

Adaptation, Physiological↗
PubMed1998

Prospective randomized comparison of phacoemulsification cataract surgery with a 3.2-mm vs a 5.5-mm sutureless incision.

PURPOSE: To report sutureless cataract surgery by phacoemulsification with a 3.2-mm surgical incision compared with a 5.5-mm surgical incision. METHOD: In a prospective, randomized, masked clinical trial of phacoemulsification cataract surgery, 55 eyes (55 patients) had a 3.2-mm incision and 56 eyes (56 patients) had a 5.5-mm incision. All incisions were in the superior vertical meridian, commenced 1.5 mm posterior to the limbus, and extended into the cornea for a total length of 2.5 to 3.0 mm. In a masked fashion, astigmatism was monitored by keratometry, and logMAR visual acuity was determined both with and without best correction throughout a mean follow-up of 33.9 months. RESULTS: Statistically significant differences were seen in favor of the 3.2-mm incision group at the final examination for astigmatism (Cravy analysis) and uncorrected visual acuity (-0.18 vs -0.88 diopter, P < .001; logMAR, 0.14 vs 0.26, P = .04). CONCLUSIONS: Over the long term, phacoemulsification with a 3.2-mm incision is associated with significantly less astigmatic shift and better uncorrected visual acuity than is phacoemulsification with a 5.5-mm incision. A small incision with a foldable intraocular lens has long-term benefits.

Aged↗
PubMed1999

Comparative corneal topography and refractive variables in monozygotic and dizygotic twins.

PURPOSE: To investigate the role of heredity in determining corneal shape, axial length, and overall refractive error. METHODS: Twenty monozygotic and 19 dizygotic twin pairs, age 12 to 73 years, were enrolled in the study. Zygosity was determined by physical similarity and by responses to questions adapted from surveys. Two twin pairs were excluded because of undetermined zygosity and one pair because of keratoconus (both siblings). Refractive error was determined by an automated refractor. Manifest refraction was also recorded, as well as cycloplegic refraction in subjects under age 18 years. Corneal topography data and manual keratometer readings were also obtained. Axial lengths were determined by A-scan ultrasound. Data were analyzed by Student t tests only in the right eye. Left-eye data were comparable for all variables. RESULTS: Mean intrapair difference in refractive error (spherical equivalent) was less for monozygotic than for dizygotic twins (RE: 0.41 vs 1.53; P = .001). Mean intrapair difference in axial length was less for monozygotic twins (RE: 0.39 vs 0.76 mm; P = .031). Corneal topography data (power and meridian) in all zones (3, 5, and 7 mm) also showed smaller mean differences among monozygotic pairs than dizygotic, but the difference was statistically significant only for the 5-mm zone. In addition, most Holladay Diagnostic Summary variables that were studied did not show any statistically significant differences. CONCLUSIONS: Axial length and overall refractive error have a significant genetic basis. Corneal topography data appear to have other overriding determining factors for several of the variables studied.

Adolescent↗