首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
BACKGROUND: The purpose of the present study was to evaluate a computerized test for measurement of contrast sensitivity thresholds under variable ambient and glare luminance levels.METHODS: A total of 40 eyes of 40 healthy subjects were examined with the FF-CATS and the Functional Acuity Contrast Test (FACT) at 0.167 cd/m(-2) (mesopic) and 167 cd/m(-2) (photopic). Measurements were performed twice with and without glare in a randomized fashion. Tests were evaluated according to three criteria: (1) repeatability, (2) discriminative ability, and (3) validity.RESULTS: The FF-CATS showed a higher discriminative ability between the two groups compared to the FACT charts. Under photopic conditions, the COR value was 0.39 for the FF-CATS and 0.26 for the FACT charts; under mesopic illumination, the COR value for the FF-CATS was 0.46 and 0.36 for the FACT charts.CONCLUSION: The FF-CATS is a reliable, sensitive, valid, and flexible test system for the determination of visual acuity and contrast sensitivity thresholds under variable ambient and glare luminance conditions.  相似文献   

2.
PURPOSE: To evaluate the comparability between the well-established Sheridan-Gardiner test (SGT) and a new type of visual acuity test, called the R?der test (RT = broken wheel test) in pre-school children, and to compare test durations of these infant visual acuity tests. SUBJECTS AND METHODS: The RT consists of 16 cards with visus values of 0.16, 0.2, 0.25, 0.3, 0.5, 0.6, 0.8 and 1.0. One pair of cards depicting a car is used for testing. On one of the cards the car has intact wheels, on the other the wheels are incomplete, symbolized by a Landolt ring. The child must indicate, at a viewing distance of 3 meters, which of the wheels is incomplete. The SGT consists of seven visus plates: 5/60, 5/36, 5/24, 5/18, 5/12, 5/9 and 5/6. Each level is tested with one letter and can be repeated by the presentation of a further letter (A, H, O, T, U, V, X). The examination distance is 5 meters. The child must indicate, with reference to a card depicting all seven symbols, which letter the examiner is showing. The SGT and RT were performed in a randomized cross-over sequence in 30 children (20male, 10 female) of pre-school age (from 2 years up to and including the age of 5 years, mean 3.4 years +/- 0.77 SD, median 3.0 years). In all cases, the right eye was examined first. Examination duration was assessed for each acuity test, and for each eye separately with a stopwatch. The instruction time was not considered. The possible visual acuity values of both bests were replaced by a unified scale of visual acuity levels (ranging from 1 to 10). A difference of at least two levels was considered as relevant. The results were compared by means of the sign test at a significance level of 0.05. RESULTS: In particular, for higher visual acuity levels there were considerable differences, with SGT generally showing better results than RT: in 11 of 29 children, in both eyes RT values turned out to be at least 2 lines better than those obtained with SGT. The contrary situation, i. e., favoring SGT by more than 2 lines compared to RT, never occurred. According to the sign test, these differences were significant (p < 0.001). SGT revealed also clearly better visual acuity levels in those 22 children out of the 30, who exhibited differences by 2 lines or more in at least one eye (p < 0.001). The examination procedure with RT revealed problems in making the required directional decisions, especially between 2 and 4 years of age. This might interfere with the test interpretation and lead to distortion of the RT results. Total examination duration did not differ considerably between SGT (1.6 to 5.8 minutes, median 3.0 minutes) and RT (1.6 to 9.4 minutes, median 4.6 minutes), respectively. CONCLUSIONS: The Sheridan-Gardiner test generally shows better results than the new R?der (RT = broken wheel) test in pre-school children. Problems in making the required directional decisions may interfere with RT in this age group.  相似文献   

3.
4.
5.
Purpose

To demonstrate a novel, alternative endothelium Descemet membrane layer (EDM) orientation method in Descemet membrane endothelial keratoplasty (DMEK) that does not involve prior ink or trepanation marking of the graft, or intraoperative ocular coherence tomography (OCT) guided graft implantation during surgery, thus preventing the occurrence of an upside-down graft implantation that leads with certainty to primary graft failure.

Methods

From 2017 to early 2020, 500 eyes underwent DMEK operation using the “bubble-tap” technique first described from Dr. Perdikakis in the department of ophthalmology of St.-Johannes- Hospital in Dortmund in Germany. Primary graft failure and re-bubbling results following “bubble-tap” assisted DMEK are presented.

Results

Primary graft failure due to upside-down graft implantation was not observed in any patient. Re-bubbling was performed in 4.8% of the eyes. In 1.8% of the cases, a re-DMEK was performed due to a graft failure.

Conclusion

The “bubble-tap” technique is a novel, reliable and easy to master orientation method of EDM that enables the surgeon to perform DMEK with safety even in complicated cases with poor visibility in the anterior chamber, while it yields superior or equal results in comparison to other graft marking methods or intraoperative OCT-guided graft implantation.

  相似文献   

6.
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate the binocular and accommodative function in children wearing dual focus (DF) MiSight® contact lenses (CLs) for...  相似文献   

7.
Graefe's Archive for Clinical and Experimental Ophthalmology - Measuring quality of life in keratoconus is important and demands for well-constructed instruments and scales. To date, the...  相似文献   

8.
9.
10.
PURPOSE: To investigate the choroideremia (CHM) gene of one affected male and one obligate carrier in a Japanese family with choroideremia, and to characterize the related clinical features. METHODS: We examined one affected man and one carrier woman from a Japanese family. Genomic DNA was extracted from leukocytes of peripheral blood collected from the affected man and his daughter, who is an obligate carrier of choroideremia. Exons 1-15 of the CHM gene were amplified by polymerase chain reaction (PCR) and directly sequenced. We performed ophthalmic examinations including best-corrected visual acuity, slit-lamp examination, fundus examination, electroretinography, and Goldmann perimetry. RESULTS: A novel (967-970+2)delAAAGGT mutation was detected in the CHM gene. The affected man was hemizygous and had night-blindness, chorioretinal atrophy spreading from the posterior pole to the mid-periphery, and bareness of the sclera. His daughter was a heterozygous carrier who had chorioretinal atrophy and mottled appearance of the retinal pigment epithelium. CONCLUSION: A novel (967-970+2)delAAAGGT mutation existed in the CHM gene of a Japanese family with choroideremia.  相似文献   

11.
12.
13.
14.
Purpose: This implementation study evaluated orthoptists’ use of an educational cartoon (“the Patchbook”) and other measures to improve compliance with occlusion therapy for amblyopia.

Methods: Participating orthoptists provided standard orthoptic care for one year, adding the Patchbook in the second year. They attended courses on compliance and intercultural communication by communication skills training. Many other compliance-enhancing measures were initiated. Orthoptists’ awareness, attitude, and activities regarding noncompliance were assessed through interviews, questionnaires, and observations. Their use of the Patchbook was measured. The study was performed in low socio-economic status (SES) areas and in other areas in the Netherlands. It was attempted to integrate education on compliance into basic and continuing orthoptic training.

Results: The Patchbook was used by all 9 orthoptists who participated in low-SES areas and 17 of 23 orthoptists in other areas. Courses changed awareness and attitude about compliance, but this was not sustained. Although orthoptists estimated compliance during patching at 70%, three-quarters never suspected noncompliance during a full day of observation in any of their patients. Explanations to parents who spoke Dutch poorly were short. In the second year, explanations to children were longer. Implementation of all 7 additional compliance-enhancing measures failed. Education on compliance was not integrated into orthoptists’ training.

Conclusion: Almost all orthoptists used the Patchbook and, as another study demonstrated, it proved to be very effective, especially in low-SES areas. Duration of explanation was inversely proportional to parents’ fluency in Dutch. Noncompliance was rarely suspected by orthoptists. Although 7 additional compliance-enhancing measures had been conceived and planned with the best intentions, they were not realized. These required extra, unpaid time from the orthoptists, which is especially scarce in hospitals in low-SES areas where the educational cartoon is most needed.  相似文献   


15.
16.
17.
Background It is believed that the vascular or primary vitreous, with the exception of the later Cloquet's canal, gradually disappears and is substituted by the avascular or secondary vitreous. It ] is known that it is possible topographically to objectify mats of fibril concentrations (membranelles or tractus) of stronger light reflection inside the adult vitreous. These concentrations open up in the shape of a funnel from the papilla or Cloquet's canal towards the front of the vitreous. Methods This was a light microscopy investigation on human eyes between the embryonal stage of 3.2 cm and the fetal stage of 12.5 cm and eyes 8 months and 2 years old with persistent vessels of the vitreous. Results The investigation showed that at the embryonal stage the vitreous body is threaded from behind by branches (mats) of the hyaloid artery and from in front by vessels (mats) that go over the rim of the optic cup, i.e., the later vitreous base. Vitreous structures, in the form of horsetail-shaped fibril concentrations, could already be observed histologically in the fetal stage with the disappearance of embryonal blood vessels. These structures begin in the vitreous base, go into the vitreous, run parallel to the retina, and then go to the back of the vitreous and towards the lens. The physiological mats of vitreal fibril concentrations (membranelles or tractus) and the pathological branches of the persistent hyaloid artery, topographically correspond to the mats of the obliterated embryonal blood vessels of the vitreous, These mats grow in relation to the bulbous growth. Conclusions In these investigations an attempt has been made to clarify the question of which embryonal blood vessels, which embryonal and fetal lengths, which different physiological tractus of the vitreous body and which different pathological features of the persistent hyaloid artery correspond.  相似文献   

18.
Researches of glaucoma visual function damage, hemorrheololgy, ocular rheography and other related multiplex factors, with computed multifactorial stepwise regresion analysis, indicate that the elevation of intraocular pressure (IOP) is not the only factor to induce visual impairment. POAG patients are shown to have markedly reduced diastolic purfussion pressure in ophthalmic artery, besides prolonged filling time of the retinal artery and vein, diminished erythrocyte deformability and increased platelet adhesion rate. The characterility of ocular rheographic changes in POAG patients of controlled IOP suggest that the abnormal changes of hemorrheololgy be responsible for the damage of visual function. The abnormal changes of plasma viscosity, blood apparent viscosity, blood viscoelasticity, hematocrit, mean red cell volume etc could be found in addition to the reduction of PO2, SQ2% and trace elements (Cr, Zn, Mg, Fe) in patients with POAG. Computed multiply stepwise regression analysts and Bayes discrimination were made among the deteriorate rate of quantitative visual field and 28 factors from the combined investigation. Only the hemorrheological index could be introduced into the multiply regression equations. The more the damage of visual function in POAG patients, the more accurate the discriminatory effect. Based upon the results, and the reports of articles published as well as the search of 1982-1989 Compact Combridge MEDLINE Medical data base, the new clinical concept could be presented that POAG might belong to the scope of blood hyperviscosity syndromes. When IOP elevation and the decrease of ocular artery pressure existed, the damage of visual function in POAG patients should be deteriorated.  相似文献   

19.
20.
BACKGROUND . Merkel cell tumor is an uncommon, aggressive neoplasm of the skin, now regarded as a neuroendocrine carcinoma. Eyelids are among the sites where it can develop, often mimicking a benign process. The purpose of this report is to describe two new cases and to discuss briefly the problems of diagnosis and treatment. METHODS . Two patients with Merkel cell tumor of the eyelids are described. In both cases, the original clinical diagnosis was chalazion. Progressive growth of the lesion identified it as a tumor some 2-7 months after it was first noticed. The patients were treated by surgical excision of the tumor tissue, and only one by a course of local radiotherapy. The visual acuity was measured with Snellen fractions. The dose of local radiotherapy is given in cGy. RESULTS . Histopathological and immunohistochemical studies identified the lesion as a neuroendocrine carcinoma, consistent with Merkel cell tumor. The natural history was marked by aggressive behavior in one case, and by a delayed recurrence in the other, requiring different therapeutic approaches. CONCLUSION . Merkel cell carcinoma of the eyelid is a tumor that ophthalmogists should be aware of, as early diagnosis is a prerequisite for successful treatment. Rapid recurrence of any chalazion in a middle-aged or elderly patient should therefore prompt its histological examination to exclude the possibility of a malignant tumor.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号