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1.
To investigate normal light scattering and cataract formation, the anterior eye segments of farmed Atlantic salmon (Salmo salar) reared in fresh water and sea water were documented in vivo for the first time with a Topcon SL-45 Scheimpflug camera. A total of 40 fish from the fresh-water-rearing period, obtained from 2 groups of identical age but showing a different growth rate, and 24 fish from the sea-water-rearing period, sampled from 2 groups with identical age but being fed different food brands, were included in this study. The fish were anaesthetized before examination. Due to the naturally wide pupil, no mydriatic compound was applied. All fish were removed from the water for photography, which was performed for each eye in 0 degrees = vertical slit position. Images were recorded on Kodak Tmax 400 black-and-white film. Microdensitometric image analysis of all negatives was performed using a Joyce-Loebl online microdensitometer. In spite of the virtual absence of an anterior chamber gap between cornea and lens and very little light scattering in the normal fish lens, a small number of distinct layers could be reproducibly identified in the lens. While there was little abnormal light scattering which could point to cataract development in young fish from the fresh water period, the evaluation of the lenses from the 2 sea water groups showed the presence of specific forms of cataract especially in the cortical and supranuclear layers. There were significant differences between the groups fed different food brands at the sea water site. In conclusion, Scheimpflug photography proved to be applicable to eye research in fish in vivo. It is suggested that this method should be employed for reproducible documentation as an extension to slit lamp monitoring in experimental research to reveal causative factors for cataracts in farmed fish.  相似文献   

2.
A group of 160 Wistar rats (both sexes) from a larger chronic inhalation toxicity study was monitored at baseline and after 1 and 2 years with a photo-slitlamp microscope and a direct ophthalmoscope to record spontaneous age-related eye lesions and treatment-related eye lesions over a period of 24 months. A second group from the same study was monitored at the start and after 5 months of a 6-month posttreatment period immediately following the inhalation period. Rats were nose-only exposed for 6 h/day, 7 days/week, for 2 years to low (3 microg/l) or high (10 microg/l) total particulate matter concentrations of room-aged cigarette sidestream smoke (RASS) or diesel engine exhaust (DEE). Control animals were exposed to filtered fresh air. All ophthalmological examinations were performed in mydriasis, and relevant observations were documented on color slide film. At baseline, all animals with eye lesions were excluded from the study. After 1 year, only minor lesions were found: retrolental opacities (14%) and a few cases of corneal dryness with reddish lid margins. After 2 years, 23% of the animals had unilateral or bilateral retrolental opacities, but the most frequent eye lesions were posterior subcapsular cataracts (PSC, 32%). Water clefts and spokes were found in 11% of the lenses and mature cataracts in 6%. All other eye lesions observed were much less frequent. There were a few cases of glaucoma, corneal dryness and stromal neovascularization. The frequency and type of lesion in animals monitored from the start of the posttreatment period was comparable to what was seen after 2 years. Toward the end of this period the frequency of mature cataracts went up to 9% and that of (secondary) glaucomas to 5%. None of the eye lesions observed showed any association in frequency or severity of expression to the treatment, either RASS or DEE, or to the sex of the animals. In comparison to the (limited) literature data available, far fewer corneal lesions were found in this study, but PSCs and mature cataracts were more frequent. Strain differences may influence these parameters. This study provided valuable information on the nature and frequency of spontaneous age-related eye lesions (0-56%, depending on the tissue) in long-term toxicity studies in Wistar rats.  相似文献   

3.
BACKGROUND: Light scattering properties of the cornea and lens change in relation to age. This process is influenced by noxious factors which may induce the formation of cataracts. Four different camera types based on the Scheimpflug principle have been developed for documentation and evaluation of light scattering in the eye. Topcon SL-45. Zeiss SLC, Oxford CASE 2000, Nidek EAS 1000. Only the SL-45 and EAS 1000, however, have found a wider application in clinical and experimental studies. MATERIAL AND METHODS: Documentation of the eye with a Scheimpflug system is performed in a dark room after mydriasis induction. The rotating axis of the camera is aligned to the optical axis of the eye with fixation devices. Four meridians have been found appropriate for routine documentation. Image analysis is based on peak height and distance evaluation of 2 layers in the cornea and 10 layers in the lens. Standardization devices allow correction of technical differences in the recording process. RESULTS: Evaluation of the ageing properties of the lens has evidenced typical density developments for each individual layer, the cortex increasing in density earlier than the nucleus. Cataract classification using a Scheimpflug camera provides an objective characterization of cataract type and progression. The outcome of surgical procedures changing the refractive power of the eye can be evaluated with a Scheimpflug camera as well. Its application in studies dealing with the ocular effects of Quinolones and HMG-CoA-reductase inhibitors, has demonstrated that Scheimpflug photography is the method of choice for establishment of a safety profile for a new drug. CONCLUSIONS: Scheimpflug photography has proven to be ideal for objective documentation of the anterior eye segment in human and animal eyes, although both documentation and image analysis demand technical expertise to be reproducible.  相似文献   

4.
PURPOSE: To determine whether an ocular blunt trauma activates anterior ocular segment (cornea and lens) by examining the expression patterns of c-fos and c-jun mRNAs in these tissues of an eye of adult rat following a blunt trauma. SETTING: Department of Ophthalmology, Wakayama Medical University School of Medicine, Kimiidera, Wakayama, Japan. METHODS: Adult Wistar rats (n=36) were generally anesthetized by ether inhalation. One eye was hit with an iron sphere (30 gram) that fell to the eye from 1 m. After the procedure, the animals were killed and the affected eye was enucleated at 15, 30, 60, 120, and 180 minutes. In situ hybridization using radiolabeled oligoprobes was used to detect mRNAs of c-fos and c-jun in tissue. RESULTS: The c-fos and c-jun mRNAs were not detected in the epithelium of uninjured cornea and lens by in situ hybridization. The mRNAs for c-fos and c-jun were then detected in corneal epithelium from 15 to 60 minutes posttreatment, and were no longer observed thereafter. In lens epithelium, mRNA for c-fos or c-jun were transiently detected from 15 to 60 minutes or 30 minutes posttreatment, respectively. CONCLUSION: The c-fos and c-jun mRNAs were transiently expressed in corneal and lens epithelial cells after blunt trauma. Ocular blunt trauma activates corneal and lens epithelial cells without apparent corneal ablation or direct injury in the lens epithelium. Such activation in lens epithelium might be involved in cataractogenesis.  相似文献   

5.

Background

Dry eye disease is a common ocular surface disease that significantly affects the quality of life. Little is known about a potential impact of the disease on corneal morphology. This study was carried out to investigate for the first time if dry eye disease induces changes in corneal density and thickness.

Methods

In total 97 patients suffering from dry eye disease and 33 healthy age-matched individuals were included in this prospective, randomized study. Corneal morphology was documented with Scheimpflug photography and analyzed for central corneal thickness and corneal density in five anatomical layers (i.e. epithelium, Bowman membrane, corneal stroma, Descemet membrane and endothelium).

Results

Corneal density was significantly reduced in the epithelium (p?=?0.0053), Bowman membrane (p?=?0.0049) and Descemet’s membrane (p?=?0.0385) in patients with dry eye syndrome compared to healthy controls. This decrease was age-dependant. Furthermore, central corneal thickness was significantly reduced in patients with dry eye syndrome compared to the control group (p?=?0.0495). The change was again dependent on age with lower values at higher age. Central corneal thickness increased with age in the control group.

Conclusion

The results of this study indicate that corneal morphology is subject to significant alterations in patients with dry eye disease. Scheimpflug photography provides not only unique information in lens trials but is also able to detect changes of corneal anatomy. However, further investigations with other anterior segment imaging techniques, such spectral domain optical coherence tomography (SD OCT/Pentacam®) are necessary to further evaluate the clinical consequences of these findings.  相似文献   

6.
The effect of vitamin E acetate (VEA) eye drops on naphthalene-induced cataract in rats was investigated by Scheimpflug image analysis. The control group was administered only naphthalene (1 g/kg), while the other group was additionally given 1% VEA eye drops into both eyes 5 times a day every day for 9 weeks from the start of naphthalene treatment. During those 9 weeks, the changes of the crystalline lens were documented by an anterior eye segment analysis system (EAS-1000, NIDEK) once a week in mydriasis (Mydrin-P, Santen Pharmaceutical Co., Ltd.). The characteristic density values of the anterior deeper cortex regions were measured. The light scattering intensity of lenses from VEA eye drop-treated animals was significantly lower than that of animals without VEA treatment. This difference was found 1 week, 4 weeks, and from 7 to 9 weeks after the start of naphthalene application. VEA eye drops may have the potential to delay the progression of naphthalene-induced cataract in rats.  相似文献   

7.
A 22-year-old man presented with diminution of vision in the left eye 1 month after sustaining an injury from a high-voltage electric current to the left side of his head. Slitlamp examination and Scheimpflug imaging confirmed the typical anterior subcapsular lenticular opacities in the left eye and also documented early anterior subcapsular vacuoles in the right eye. Based on history, the electric shock wound, and the typical appearance of the opacities, an electric cataract was diagnosed. The difference in lens density between the 2 eyes was also documented. The best corrected visual acuity (BCVA) was 20/20 in the right eye and counting fingers at 1 foot in the left eye. Phacoaspiration and posterior chamber intraocular lens implantation were performed in the left eye. Postoperatively, the BCVA improved to 20/20. The developmental mechanisms of these opacities after exposure to an electric current and the role of Scheimpflug imaging in assessing the earliest subclinical manifestations of electric cataract injuries are discussed.  相似文献   

8.
Dynamic light scattering (DLS) measurements were conducted with lowest intensity levels on human eye lenses (3.2 mW/cm2) within measurement times of 3–5 s. A characterisation of the human eye under in-vivo conditions along the optical axis is given and a careful interpretation of the data is made, referring not only to in-vitro results of investigated solutions of lens chemistry and various crystallin fractions but also to measurements performed on intact human lenses under various scattering angles. The clinical study was expanded to 79 subjects with ages varying from 9 to 85 years with no serious diseases of the ocular lenses. A normalisation of Scheimpflug photography density data to the data obtained by DLS enables comparison of the two techniques and shows good agreement. The bimodal character of the viscoelastic properties of healthy eye lenses was confirmed; with an assumed viscosity of 2 cP, the mean size parameter of the smaller component is 5.13±1.6 nm and of the polymeric fraction 690 nm.  相似文献   

9.
PURPOSE. To report the Scheimpflug and clinical findings in a case of pediatric posterior capsule rupture due to blunt ocular trauma. METHODS. Interventional case report. Analysis of Scheimpflug findings and review of literature. RESULTS. An 11-year-old boy presented 2 days after blunt trauma to the left eye with a slingshot. On examination his best-corrected visual acuity (BCVA) was 20/20 in the right eye and 20/400 in the left. Slitlamp examination (left eye) revealed a Vossius ring, traumatic cataract, and traumatic posterior capsular rupture (TPCR).The contour of the posterior bulge corresponded to the edges of the TPCR. Scheimpflug imaging (Pentacam 70700: Oculus, Wetzlar, Germany) confirmed traumatic cataract in region of TPCR evidenced by increased lens density at cortex-vitreous interface, absence of vitreous prolapse into the anterior chamber, and the amount of residual nucleus. The extent of the TPCR in the greatest and least dimensions was documented before and after intraocular lens (IOL) implantation. Intraoperatively, TPCR was evident and phacoemulsification with IOL implant was performed. Postoperatively, his BCVA improved to 20/20 in the left eye with a well-centered in-thebag IOL as found on slit lamp and Scheimpflug images. CONCLUSIONS. This report highlights the use of Scheimpflug imaging in isolated posterior capsule rupture following closed globe injury, to visualize and quantify the size of posterior capsule rupture and its role in management.  相似文献   

10.
AIM: Evaluation of potential side effects of photon radiotherapy on the transparency of the lens. METHODS: The anterior segments of 14 phakic eyes from patients suffering from subfoveal neovascularisation as a result of age related macular degeneration (AMD) were documented by Scheimpflug photography (Topcon SL-45, Kodak Tmax 400) before the start of radiotherapy as well as 6 and 12 months afterwards. All negatives were evaluated by microdensitometry, and peak heights for distinct layers of the lens were used for statistical comparison. External beam radiotherapy (6 MeV photons) consisted of a total dose of 20 Gy, delivered as 10 fractions of 2 Gy. RESULTS: Six and 12 months following irradiation statistical comparison of the ratios in density change of lenses from irradiated versus non-irradiated fellow eyes revealed statistically significant (p相似文献   

11.
We report a case of an 11-year-old boy who presented two days after blunt trauma to the left eye with a slingshot. On examination his best corrected visual acuity (BCVA) was 20/20 in the right eye and 20/400 in the left eye. Slit-lamp examination of the left eye revealed a Vossius ring, traumatic cataract, traumatic posterior capsule tear (PCT). The contour of the posterior capsule bulge corresponded to the edges of the PCT. Rotating Scheimpflug imaging (Pentacam 70700:Oculus, Wetzlar Germany) confirmed the traumatic cataract in the region of the PCT visualized as increased lens density at the cortex-vitreous interface. The extent of the PCT in the greatest and least dimensions was documented before and after intraocular lens (IOL) implantation. Intra-operatively, the PCT was evident and phaco-emulsification with an IOL implant was performed. Postoperatively, his BCVA improved to 20/20 in the left eye with a well-centered in-the-bag IOL as found on slit-lamp and Scheimpflug images.  相似文献   

12.
PURPOSE: To compare the accuracy of lens transparency evaluations by Scheimpflug image in the anterior nucleus of the lens before and after pupil dilatation. METHODS: Scheimpflug lens images were recorded in 70 eyes of 38 subjects (age: 28-75 years) before and after pupil dilatation, and light scattering intensity measurements before and after dilatation were compared. RESULTS: There was a significant positive correlation between the light scattering intensity before and after dilatation at the anterior cortex, anterior nucleus, and central clear zone of the lens (r > 0.9, P <.0001). CONCLUSIONS: It is possible to estimate the transparency in the anterior nucleus of the lens from the Scheimpflug image without pupil dilatation. If nuclear type cataracts are regarded as a structural marker of aging in epidemiological studies, measuring the light scattering intensity in the anterior nucleus of the lens without dilatation seems to be a safe, useful, and quantitative method.  相似文献   

13.
PURPOSE: To demonstrate that corneal light-backscatter can be measured objectively during corneal swelling by optical coherence tomography (OCT). METHODS: One eye (randomly selected) of 20 non-contact-lens wearers (10 men and 10 women; mean age, 35.6 +/- 9.6 years) was patched during 3 hours of soft contact lens (SCL) wear. The contralateral eye acted as the control. Central corneal images were captured before and after SCL wear at 20-minute intervals over 100 minutes using optical coherence tomography (OCT) to obtain corneal thickness and light-backscatter profiles. OCT backscattered light of the epithelial layer (decided by the thickness measurements) and 10 equally divided layers of the remaining cornea were analyzed with a custom software program. Two baseline measurements were taken at different visits before lens wear to test the repeatability of light-backscatter measurements. RESULTS: From two baseline measurements, repeated measurements showed good repeatability of normalized backscatter results. Immediately after contact lens removal, total central corneal thickness increased significantly by 13.8% +/- 2.3% (mean +/- SD) compared with baseline (P = 0.0001, paired t-test) and then decreased during the deswelling course. Corneal backscattered light changed significantly (repeated-measures ANOVA [Re-ANOVA]: F((50, 950)) = 2.22, P = 0.0001) after lens wear, and a significant increase in backscatter was found in the epithelial layer (36.4%) and the most posterior corneal layer (35.6%) immediately after lens removal (post hoc test, P = 0.005). There was a strong correlation (r = 0.9375, P < 0.05) between the change in backscatter and corneal swelling during the deswelling period. The backscatter recovery rate was approximately the same for both epithelial and posterior layers after lens removal. CONCLUSIONS: Light-backscattering analysis with OCT seems to be a promising and repeatable method of objectively measuring corneal backscatter. This study has demonstrated that corneal backscattered light increased in the anterior and posterior layers of the cornea during corneal swelling induced by contact lens wear and eye closure.  相似文献   

14.
Dynamic light scattering (DLS) measurements were conducted with lowest intensity levels on human eye lenses (3.2 mW/cm2) within measurement times of 3–5 s. A characterisation of the human eye under in-vivo conditions along the optical axis is given and a careful interpretation of the data is made, referring not only to in-vitro results of investigated solutions of lens chemistry and various crystallin fractions but also to measurements performed on intact human lenses under various scattering angles. The clinical study was expanded to 79 subjects with ages varying from 9 to 85 years with no serious diseases of the ocular lenses. A normalisation of Scheimpflug photography density data to the data obtained by DLS enables comparison of the two techniques and shows good agreement. The bimodal character of the visco-elastic properties of healthy eye lenses was confirmed; with an assumed viscosity of 2 cP, the mean size parameter of the smaller component is 5.13±1.6 nm and of the polymeric fraction 690 nm. Received: 22 July 1996 Revised version received: 23 April 1997 Accepted: 6 May 1997  相似文献   

15.
In 1992, a ciliary sulcus-fixated, silicone, phakic posterior chamber intraocular lens (PPC IOL) (Adatomed, Fyodorov type) was implanted in both eyes of a 42-year-old white woman to correct high myopia (right eye, -17.0 diopters [D]; left eye, -11.5 D). In the right eye, localized cortical opacification was present in the anterior part of the natural lens preoperatively but did not progress during a 10-year follow-up period. With Scheimpflug photography, it was possible to detect a space between the natural lens and the IOL that was not evident on slitlamp examination. Maintenance of space between an IOL and the natural lens appears to be an important factor in preventing cataract formation after PPC IOL implantation.  相似文献   

16.
The haptic of a semiflexible anterior chamber intraocular lens (Kelman Quadraflex) broke inside the eye of a 70-year-old man. No history of major eye or head trauma could be elicited from the patient. Clinical manifestations included inferior corneal edema progressing toward the optical axis resulting from a free-floating haptic segment of the lens implant inside the anterior chamber. A significant decrease in endothelial density was documented over a short period of time. The surgical management of this case included removal of the free-floating haptic segment, removal of the lens implant, penetrating keratoplasty, and vitrectomy. Final visual acuity was 20/70.  相似文献   

17.
PURPOSE: To measure tilt and decentration of intraocular lenses (IOLs) with Scheimpflug and Purkinje imaging systems in physical model eyes with known amounts of tilt and decentration and patients. SETTING: Instituto de Optica Daza de Valdés, Consejo Superior de Investigaciones Científicas, Madrid, Spain. METHODS: Measurements of IOL tilt and decentration were obtained using a commercial Scheimpflug system (Pentacam, Oculus), custom algorithms, and a custom-built Purkinje imaging apparatus. Twenty-five Scheimpflug images of the anterior segment of the eye were obtained at different meridians. Custom algorithms were used to process the images (correction of geometrical distortion, edge detection, and curve fittings). Intraocular lens tilt and decentration were estimated by fitting sinusoidal functions to the projections of the pupillary axis and IOL axis in each image. The Purkinje imaging system captures pupil images showing reflections of light from the anterior corneal surface and anterior and posterior lens surfaces. Custom algorithms were used to detect the Purkinje image locations and estimate IOL tilt and decentration based on a linear system equation and computer eye models with individual biometry. Both methods were validated with a physical model eye in which IOL tilt and decentration can be set nominally. Twenty-one eyes of 12 patients with IOLs were measured with both systems. RESULTS: Measurements of the physical model eye showed an absolute discrepancy between nominal and measured values of 0.279 degree (Purkinje) and 0.243 degree (Scheimpflug) for tilt and 0.094 mm (Purkinje) and 0.228 mm (Scheimpflug) for decentration. In patients, the mean tilt was less than 2.6 degrees and the mean decentration less than 0.4 mm. Both techniques showed mirror symmetry between right eyes and left eyes for tilt around the vertical axis and for decentration in the horizontal axis. CONCLUSIONS: Both systems showed high reproducibility. Validation experiments on physical model eyes showed slightly higher accuracy with the Purkinje method than the Scheimpflug imaging method. Horizontal measurements of patients with both techniques were highly correlated. The IOLs tended to be tilted and decentered nasally in most patients.  相似文献   

18.
A case of Weill-Marchesani syndrome with inversion of chromosome 15   总被引:1,自引:0,他引:1  
PURPOSE: To present a case of Weill-Marchesani syndrome with corneal endothelial dysfunction due to anterior dislocation of a spherophakic lens and corneolenticular contact. METHODS: A 17-year-old woman presented with high myopia and progressive visual disturbance. She was of short stature and had brachydactyly. Her initial Snellen best corrected visual acuity (BCVA) was 20/50 (-sph 20.50 -cyl 3.00 Ax 180) in her right eye and 20/40 (-sph 16.00 -cyl 6.00 Ax 30) in her left eye. Slit lamp examination revealed a dislocated spherophakic lens touching corenal endothelium. A microspherophakic lens, hypoplastic ciliary body, and elongated zonules were confirmed on rotating Scheimpflug camera (Pentacam) and on ultrasound biomicroscopy. Specular microscopy showed corneal endothealial dysfunction. Systemic evaluation was performed, and chromosomal study showed 46, XX, inv (15) (q13qter). The patient was diagnosed with Weill-Marchesani syndrome. RESULTS: Due to impending corneal decompensation, phacoemulsification and suture fixation of the intraocular lens were performed. The operation and postoperative course were uneventful. Three months postoperatively, the visual acuity was 20/30 (OD) and 20/40 (OS) without correction, and BCVA was 20/20 (+sph 0.50 -cyl 2.00 Ax 160 : OD) and 20/25 (+sph 1.50 -cyl 3.00 Ax 30 : OS). During the follow-up period, increased corneal endothelial counts, hexagonality, and decreased corneal thickness were achieved. CONCLUSIONS: In Weill-Marchesani syndrome with a chromosomal anomaly, a dislocated spherophakic lens may cause severe corneal endothelial dysfunction due to corneolenticular contact, and prompt lensectomy is important to prevent such complications.  相似文献   

19.
Transient changes in the corneal endothelium were the earliest detectable response to low atmospheric oxygen in experimental animals. Similar changes have been reported after hard and soft contact lens wear. We describe widespread transient cell changes by wide-field specular microscopy in the normal corneal endothelium after 12 hours of a light eye patch. The relative anoxia of lid closure during normal sleep appears to be the cause of observable changes. This observation questions the safety of extended wear contact lens over a prolonged period of time, and its significance to age-related endothelial cell density reduction and cornea guttata remains to be seen.  相似文献   

20.
BACKGROUND: For the correction of refractive errors lenticular procedures are increasingly used in addition to corneal refractive surgery. One of those techniques is the implantation of intraocular lenses into phakic eyes (pIOL). Due to the close neighborhood of the implant to delicate intraocular structures, exact positioning and high postoperative stability are required. Scheimpflug photography has been shown to be a suitable instrument for the biometry of the anterior eye segment and the examination of IOL position. PATIENTS AND METHODS: Four anterior chamber phakic IOLs (pIOLs) (Bausch & Lomb NuVita) and 7 posterior chamber pIOLs (Staar ICL) were examined 1 week, 1 month and 3-6 months following implantation. At each examination 1 Scheimpflug slit image and 1 infrared retroillumination image were taken using the anterior eye segment analysis system EAS-1000 (Nidek Co., Gamagori, Japan). Evaluation of the images was performed with a personal computer and the software provided by the manufacturer. The distance of the pIOL to cornea and human lens was calculated and incidence and amount of pIOL rotation around the optical axis and potential crystalline lens opacification were assessed. RESULTS: The distance between the anterior chamber pIOL and the cornea 1 week after implantation was 1.61 +/- 0.10 mm. The distances between the myopic posterior chamber pIOL and the human lens were 0.34 +/- 0.11 mm and between the hyperopic posterior chamber pIOL and the human lens 0.26 and 0.29 mm, respectively. The values were constant over a period of 3-6 months. The pIOL showed no movement or change of position around the optical axis. There was no detectable cataract formation in the human lens. CONCLUSIONS: All implanted phakic anterior and posterior chamber IOLs showed a stable position in the eye within the observation period. Scheimpflug photography is proved to be a useful technique for the postoperative evaluation of the positioning of phakic IOLs.  相似文献   

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