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At least 1,063 records · Page 59Linked to original sources

Strategy to reduce the number of patients perceiving impaired visual function after cataract surgery.

PURPOSE: To reduce the number of patients who perceive more difficulties performing daily life activities 6 months after cataract extraction than before surgery. SETTING: Surgeons at 4 surgical units participating in the yearly outcome studies organized by the Swedish National Cataract Register. METHODS: This study comprised surgical outcomes data and completed Catquest results before and after surgery collected from consecutive patients during a 1-month period yearly since 1995. The reasons for a no-benefit outcome from 1995 to 1997 were identified. During the 1-month study period in 1999, a strategy was launched to reduce postoperative anisometropia and disturbances from cataract in the fellow eye through better surgical planning. RESULTS: The percentage of patients with a no-benefit outcome who had anisometropia or cataract in the fellow eye as a probable reason for the outcome decreased from 27.3% and 13.0%, respectively, in the 1995 to 1997 study to 10.5% and 10.5%, respectively, in the 1999 study. Other reasons for a no-benefit outcome such as ocular co-morbidity or few preoperative problems increased in frequency, presumably as a result of a change in case mix. CONCLUSIONS: A strategy to reduce the number of patients perceiving more difficulties in performing daily life activities after cataract extraction than before surgery was tested. The number of patients with reasons for a poor outcome that the study focused on was reduced. Patients who gave reasons for a poor outcome other than anisometropia or cataract in the fellow eye increased in frequency, probably as a result of a change in case mix.

Activities of Daily Living↗

Detecting early glaucoma by assessment of retinal nerve fiber layer thickness and visual function.

PURPOSE: To compare the abilities of scanning laser polarimetry (SLP), optical coherence tomography (OCT), short-wavelength automated perimetry (SWAP), and frequency-doubling technology (FDT) perimetry to discriminate between healthy eyes and those with early glaucoma, classified based on standard automated perimetry (SAP) and optic disc appearance. To determine the agreement among instruments for classifying eyes as glaucomatous. METHODS: One eye of each of 94 subjects was included. Healthy eyes (n = 38) had both normal-appearing optic discs and normal SAP results. Glaucoma by SAP (n = 42) required a repeatable abnormal result (glaucoma hemifield test [GHT] or corrected pattern standard deviation [CPSD] outside normal limits). Glaucoma by disc appearance (n = 51) was based on masked stereoscopic photograph evaluation. Receiver operating characteristic (ROC) curve areas, sensitivities, and specificities were calculated for each instrument separately for each diagnosis. RESULTS: The largest area under the ROC curve was found for OCT inferior quadrant thickness (0.91 for diagnosis based on SAP, 0.89 for diagnosis based on disc appearance), followed by the FDT number of total deviation plot points of < or =5% (0.88 and 0.87, respectively), SLP linear discriminant function (0.79 and 0.81, respectively), and SWAP PSD (0.78 and 0.76, respectively). For diagnosis based on SAP, the ROC curve area was significantly larger for OCT than for SLP and SWAP. For diagnosis based on disc appearance, the ROC curve area was significantly larger for OCT than for SWAP. For both diagnostic criteria, at specificities of > or =90% and > or =70%, the most sensitive OCT parameter was more sensitive than the most sensitive SWAP and SLP parameters. For diagnosis based on SAP, the most sensitive FDT parameter was more sensitive than the most sensitive SLP parameter at specificities of > or =90% and > or =70% and was more sensitive than the most sensitive SWAP parameter at specificity of > or =70%. For diagnosis based on disc appearance at specificity of > or =90%, the most sensitive FDT parameter was more sensitive than the most sensitive SWAP and SLP parameters. At specificity > or = 90%, agreement among instruments for classifying eyes as glaucomatous was poor. CONCLUSIONS: In general, areas under the ROC curve were largest (although not always significantly so) for OCT parameters, followed by FDT, SLP, and SWAP, regardless of the definition of glaucoma used. The most sensitive OCT and FDT parameters tended to be more sensitive than the most sensitive SWAP and SLP parameters at the specificities investigated, regardless of diagnostic criteria.

Diagnostic Techniques, Ophthalmological↗

Ibuprofen and visual function. Prospective evaluation.

Eye evaluations before and after 24 weeks of treatment with either ibuprofen (Motrin) or aspirin did not show eye toxicity with either drug in a double-blind study of 78 patients with osteoarthritis. The possibility of eye complications resulting from ibuprofen therapy suggested in two earlier reports has not been confirmed in clinical usage in other countries or in clinical trials in the United States.

Adult↗

Occipital cortex in man: organization of callosal connections, related myelo- and cytoarchitecture, and putative boundaries of functional visual areas.

Human area 17 is known to contain a single (the primary) visual area, whereas areas 18 and 19 are believed to contain multiple visual areas (defined as individual representations of the contralateral visual hemifield). This is known to be the case in monkeys, where several boundaries between visual areas are characterized by bands of callosal afferents and/or by changes in myeloarchitecture. We here describe the pattern of callosal afferents in (human) areas 17, 18, and 19 as well as their cortical architecture and we infer the position of some visual areas. Sections from occipital lobes of 6 human brains with unilateral occipital infarctions have been silver-impregnated for degenerating axons, thereby revealing callosal afferents to the intact occipital cortex. Their tangential distribution is discontinuous, even in cases with large lesions. A band of callosal afferents straddles the area 17/18 boundary, whereas the remainder of area 17 and a 15-45 mm wide stripe of area 18 adjacent to the callosal band along the 17/18 border are free of them. Patches of callosal afferents alternate with callosal-free regions more laterally in area 18 and in area 19. We conclude that, in man, a second visual area (analogue of V2) lies in area 18, horseshoe-shaped around area 17, and includes the inner part of the acallosal stripe adjacent to the callosal band along the 17/18 boundary. The outer part of this acallosal stripe belongs to a third visual area, which may contain dorsally the analogue of V3 and ventrally that of VP. Thus the lower parts of the second and third visual areas lie on the lingual gyrus, whereas the analogue of the macaque's fourth visual area probably lies on the fusiform gyrus. Although the proposed subdivision of the occipital cortex relies largely on the pattern of callosal afferents, some putative human visual areas appear to have distinct architectonic features. The analogue of V2 is rather heavily myelinated and its layer III contains large pyramidal neurons. Its upper part is not well delimited laterally since adjacent "V" has similar architecture. Its lower part, however, differs clearly from the adjacent "VP," which is lightly myelinated and lacks the large pyramids in layer III. The cortex lateral to "VP" is heavily myelinated and contains fairly large pyramids in layers III and V. The myeloarchitecture of the lateral part of the occipital cortex is not uniform; a very heavily myelinated region stands out in the lateral part of area 19, near the occipito-temporal junction.(ABSTRACT TRUNCATED AT 400 WORDS)

Afferent Pathways↗

Retinoids, eye development, and maturation of visual function.

Vitamin A is known to be critical for the beginning of eye development as well as for photoreception in the functional retina. Hardly anything, however, is known about whether retinoic acid (RA)-regulated gene expression also plays a role in the long intervening period, during which the neurobiological retinal structure takes shape. The eye contains a highly intricate architecture of RA-synthesizing (RALDH) and degrading (CYP26) enzymes. Whereas the RALDHs are integrated in the early molecular mechanisms through which the dorso-ventral retina organization is established, the CYP26 enzymes are not necessary for this process and no molecular targets that match their retinal expression pattern have yet been identified. In this article we describe that CYP26 expression in the mouse is most distinctive during later stages of retina formation. Throughout development CYP26A1 degrades RA in a horizontal region that extends across the retina, but during later embryonic and postnatal retina maturation this function is reinforced by another enzyme, CYP26C1. RA applications at this stage do not affect the RALDHs but cause differential changes in CYP26 expression: Cyp26a1 is up-regulated, but more rapidly by 9-cis than all-trans RA, Cyp26c1 is down-regulated, and Cyp26b1, which is undetectable in the normal mouse retina, is strongly activated in retinal ganglion cells. The dynamic regulation in RA-difference patterns by the CYP26 enzymes may set up spatial constellations for expression of genes involved in formation of retinal specializations for higher acuity vision, which are known to form over a prolonged period late in retina development.

Aldehyde Oxidoreductases↗

Visual function in hypermetropia. An electroretinographic and psychophysical study.

Dark-adapted retinal function was tested electroretinographically and psychophsysically in patients with severe hypermetropia. These patients were first tested in 1982 and were classified into three electroretinographic categories subnormal, normal and supernormal, according to the amplitudes and the b-wave to a-wave relationships of their dark-adapted electroretinographic responses. These patients were invited for a follow-up examination to examine whether the subnormal electroretinogram represented a stationary or a progressive syndrome, to correlate functional vision to the electroretinographic findings and to determine the changes in refraction and electroretinographic responses that might have occurred during an 8-year period. No significant changes were seen in the amplitudes and b-wave to a-wave relationships of the electroretinographic responses. These observations supported the initial electroretinographic classification of the hypermetropic patients and indicated that the patients belonging to the subnormal group were probably characterized by a stationary defect. The psychophysically determined thresholds at different retinal loci (from 30 degrees nasal to 40 degrees temporal) were within the normal range for all the patients regardless of their electroretinographic characteristics. Thus, the abnormal electroretinographic responses of hypermetropic patients probably did not reflect abnormal retinal function but may be accounted for by changes in the electrical resistances of extraretinal tissues relative to that of the retina itself.

Adolescent↗