German journal of ophthalmology最新文献

{"title":"Comparative investigations on water-soluble crystallins of the embryonic, fetal, and postnatal human lens during development and ageing.","authors":"N Trifonova,&nbsp;M Stamenova,&nbsp;I Boulanov,&nbsp;M Goranov,&nbsp;J Bours","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>To compare the crystallin composition of embryonic and fetal human lenses with those of postnatal and adult lenses, we investigated the crystallins of lenses of various ages (from the 5th gestational week to 55 years) by gel chromatography, isoelectric focusing, immunodiffusion, and immunoelectrophoresis. Age-related changes were calculated as relative percentages of the different classes and subclasses of crystallins. During prenatal lens development the percentages of both high- and low-molecular-weight alpha-crystallins as well as gamma-crystallins gradually increased, whereas the percentage of beta-crystallins decreased. A considerable change in crystallin composition was found immediately after birth: the relative percentage of beta-crystallins increased, whereas that of gamma-crystallins decreased. Gel-filtration analysis of crystallins from juvenile and adult lenses showed a high-molecular-weight peak, which was not found in extracts from fetal and new-born lenses.</p>","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"454-60"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20405521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An adjuvant afterloading brachytherapy device for use after orbital exenteration in patients with orbital malignancies.","authors":"A Bacskulin,&nbsp;M Ehrhardt,&nbsp;M Strietzel,&nbsp;H W Pau,&nbsp;H von Schwanewede,&nbsp;R Guthoff","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In cases of malignant diseases situated within the orbit and threaten to extend beyond it, removal of the orbit and periorbital contents may be indicated, followed by adjuvant chemotherapy or irradiation. An effective radiotherapy device for treatment of residual or suspicious cancer in the enucleated orbit consists of an external-beam radiation source (60Co) and an intraoperatively fitted mould as a guide for the flexible afterloading tubes using a 192Ir source. Considering the physical dose distribution and the local situation, this therapy permits a high dose with homogeneous dose distribution to the target area of the orbit but also allows significant dose reduction to adjunctive critical structures. Four patients with different orbital malignancies were treated by means of a combination of percutaneous radiotherapy with afterloading brachytherapy following orbital exenteration. The individual mould of the orbital cavity is modeled at the end of the operation. The technique of radiotherapy, dose distribution, and follow-up of the disease are demonstrated. Orbital malignancies with an extremely poor prognosis may profit from the application of this combined radiotherapy to avoid supraradical surgical intervention.</p>","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"484-8"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20405525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a new slice-culture method to study epithelial corneal pathophysiology in the paradigm of corneovascular interactions.","authors":"S Thanos,&nbsp;K P Steuhl,&nbsp;R Thanos,&nbsp;H J Thiel","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The cornea is a physiologically capillary-free and optically transparent tissue that subserves optimal visual function. In frequent pathological situations of diverse natural or experimental etiologies (lesions, burns, denervations, dystrophies, ulcers, infections) that involve long-lasting epithelial defects, vascular capillaries invade the cornea, resulting in opacity and reduction or loss of visual function. In view of the relative insensitivity of animal models, of the need for large numbers of animals to perform experiments, and, not least, of the painful interventions due to the very dense trigeminal innervation of the cornea in situ, we searched for alternative experimental setups to study mechanisms of corneal pathophysiology. As a first goal we developed a new slice-culture model and examined interactions between in-vitro-differentiated corneal epithelial cells and cocultured vascular endothelial cells. Corneas from enucleated eyes, from donor eyes retrieved for keratoplasty, or from animal eyes were dissected and cut along the optical axis to produce slices containing all three corneal layers. Corneal epithelial cells developed well-differentiated histotypical monolayers whose sizes were comparable with the size of the corneal surface in situ. When examined by electron microscopy, the epithelial cells formed tight contacts with each other and formed typical villous protrusions at the growing front. As a second goal we studied interactions between corneal epithelium and cocultured capillary endothelial cells. Upon encountering cocultured vascular endothelial cells, corneal epithelium exerted a strong, contact-mediated repulsion. The morphological correlates of repulsion were collapse of lamellipodial protrusions, immobilization, and cell death. These responses resulted in the inability to penetrate the corneal epithelium. The repulsive activity was exclusively localized in the epithelium, whereas stromal keratocytes were permissive for ingrowth of vascular cells. The angiorepulsive features of the cornea could be partially neutralized with aprotinin, indicating that membrane-linked proteolytic systems are involved in the interactions between corneal and vascular tissue. This coculture system may be used to characterize further the cell-signaling mechanisms and the interactions between cornea and vascular endothelial cells during pathological situations associated with angiogenesis.</p>","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"466-78"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20405523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Little effect of tissue plasminogen activator in subretinal surgery for acute hemorrhage in age-related macular degeneration.","authors":"L Hesse,&nbsp;D Meitinger,&nbsp;J Schmidt","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We studied the effect of intraoperative fibrinolysis prior to surgical evacuation of subretinal hemorrhage, which has been recommended as a valuable adjunct in the surgical treatment of submacular hemorrhage. We analyzed retrospectively the records of eight patients who underwent pars plana vitrectomy combined with subretinal injection of tissue plasminogen activator (TPA). The duration of symptoms ranged from 2 h to 14 days (median 1.5 days). During vitrectomy, TPA (6-75 micrograms) was injected subretinally through a retinotomy. After 20 min the liquified blood was surgically drained. The residual clot had to be extracted mechanically through an enlarged retinotomy site. In all patients, fibrinolysis was incomplete and an additional mechanical clot extraction was necessary. The postoperative visual acuity improved slightly in four patients, stabilized at the preoperative level in three patients, and worsened in one patient. During follow-up, one patient suffered from retinal detachment. In four patients a cataract developed. In all eyes, large defects of the retinal pigment epithelium resulted. In contrast to other authors, we did not find an acceptable liquefaction of the subretinal clot that would have facilitated surgical extraction of the hemorrhage. Therefore, a therapeutic benefit from the injection of TPA before removal of a subretinal hemorrhage was not distinct.</p>","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"479-83"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20405524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perfusion of the juxtapapillary retina and optic nerve head in acute ocular hypertension.","authors":"G Michelson,&nbsp;M J Groh,&nbsp;M Langhans","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Chronically elevated intraocular pressure (IOP) is often associated with glaucomatous optic nerve atrophy. Impaired blood flow may play a role in the pathogenesis of this disease. We present data concerning juxtapapillary retinal and optic nerve-head blood flow during acute increases in IOP. With the combination of a laser Doppler flowmeter and a scanning-laser system (Scanning Laser Doppler Flowmeter, SLDF; Heidelberg Engineering) the perfusion of the retina and the optic nerve head was quantified and visualized. Juxtapapillary retinal and optic nerve-head blood flow was measured simultaneously by SLDF during variations in IOP induced by a suction cup in nine healthy volunteers. The ocular pressure was increased for 2 min to IOP +15 mmHg, then to IOP +30 mmHg, and finally, to IOP +45 mmHg. Ocular perfusion pressure (PP) was calculated as the mean arterial blood pressure minus the IOP. The declines in juxtapapillary retinal flow as expressed in present per 10-mmHg IOP elevation ranged from 3.6% to 14.1% (median 7.4%). Over all measurements we found a significant linear relationship between juxtapapillary retinal blood flow and PP (r = 0.55, P < 0.0001). The observed decrease in optic nerve-head blood flow with increasing IOP was significantly greater as compared with the retinal blood flow decrease (8.4%/10 mmHg versus 7.4%/10 mmHg, P < 0.05). SLDF enables the quantification and visualization of perfused capillaries of the retina and the optic nerve head in high resolution. Acute elevations of IOP led to a decreases in juxtapapillary retinal and optic nerve-head blood flow of 7.4% and 8.4%/ 10-mmHg IOP increase, respectively.</p>","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"315-21"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20403247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution of proteoglycans in the trabecular tissue of eyes with neovascular glaucoma.","authors":"T Kubota,&nbsp;A Tawara,&nbsp;A Khalil,&nbsp;M Honda,&nbsp;H Inomata","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We investigated histo-chemically the composition and distribution of proteoglycans in the trabecular tissue of eyes with neovascular glaucoma. Cupromeronic blue in combination with a series of enzyme digestions and nitrous acid treatment were used. The spaces between the trabecular beams were lined by a single layer of vascular endothelium and were filled with red blood cells. A basal lamina and microfibrils were detected just beneath the newly formed vascular endothelial cells. Chondroitin-sulfate- and dermatan-sulfate-type proteoglycans were present in association with collagen fibrils in the extracellular matrix. Heparan-sulfate-type proteoglycans were present in association with the basal lamina of both the vascular endothelial cells and the trabecular cells. It is unlikely that these abnormalities in the type or distribution of proteoglycans in the trabecular meshwork have a major role in the pathogenesis of glaucoma.</p>","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"392-8"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20404388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-precision, high-speed measurement of excimer laser keratectomies with a new optical pachymeter.","authors":"M Böhnke,&nbsp;P Chavanne,&nbsp;R Gianotti,&nbsp;R P Salathé","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In excimer-laser photorefractive keratectomy (PRK) the depth of the stromal tissue ablation is calculated from calibration and empirical data but is not actually measured, since a noncontact high-precision instrument for the measurement of the actual ablation has not been available. With a newly developed method for optical pachymetry we studied the depth of corneal ablations performed with an excimer laser. The excimer laser (Schwind Keratom) was calibrated according to the manufacturers' instructions. On freshly enucleated pig eyes, planokeratectomies with a diameter of 5 mm and a planned depth of 20, 40, 80, 160, and 320 microns were performed. With a newly developed high-precision, high-speed reflectometer the corneal thickness was measured immediately before and after the keratectomy. All ablations were deeper than expected. For a planned keratectomy of 20 microns we found a mean ablation depth of 29 microns; for 40 microns, a mean depth of 51 microns; for 80 microns, a mean depth of 100 microns; for 160 microns, a mean depth of 200 microns; and for 320 microns, a mean depth of 396 microns. The differences between mean and maximal ablation values were 58.6% at the 20-micron setting, 40.9% at the 40-micron setting, 20.1% at the 80-micron setting, 11.5% at the 160-micron and 9.8% at the 320-micron setting. Ablation rates showed the highest degree of variation in the 20-micron ablation group. Absolute variations in the ablation depth increased with ablation depth. In photorefractive procedures the volume of the tissue ablated is calculated from the instrument calibration but is not actually measured. Although the greater than expected ablation depths may in part be explained by differences between human and porcine tissue, the high degree of variability in the laser ablations may have other causes. We suggest that variations in the postoperative refractive results of PRK, which are currently attributed to variations in corneal would healing, may in part be due to variations in ablation depth.</p>","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"338-42"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20404491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Confocal microscopy.","authors":"R Guthoff","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"495"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20405529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shape visualization of the anterior and posterior human cornea in vivo.","authors":"B R Masters","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A series of 60 reflected-light, rotating slit images of the human cornea in vivo are acquired with a rotating Scheimpflug camera. Each single acquired optical slice on a single meridian contains the shape of the anterior and posterior surfaces of the cornea. These 60 images are mathematically transformed into a three-dimensional volume that can be visualized on any meridian, including those images on meridians that have not been selected during the image-acquisition process. The optical distortions and aberrations of both the camera system and the eye are not included in this study using a rotating slit camera to determine the shape of both anterior and posterior corneal surfaces. The method presents the view of the anterior and posterior cornea (out to the midperipheral region) and a reference plane of the iris reflection. Further development of this technique may find clinical applications in corneal refractive surgery.</p>","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"504-7"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20405531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vivo observation of corneal nerve regeneration after photorefractive keratectomy with a confocal videomicroscope.","authors":"P Heinz,&nbsp;S Bodanowitz,&nbsp;W Wiegand,&nbsp;P Kroll","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The aim of the present study was to study corneal nerve regeneration after photorefractive keratectomy (PRK) in vivo by means of a confocal videomicroscope. A total of 25 myopic eyes of 16 patients were examined biomicroscopically and with the confocal microscope (Microphthal, Hund Company, Wetzlar, Germany) before and after PRK. The mean age of the patients was 30.4 (range 21-44) years, the mean follow-up period was 13.7 (11.0-15.1) months, the mean preoperative refraction was -5.5 (-1.75 to -9.0) D, the mean amount of attempted correction was -4.75 (-1.75 to -7.5) D, the mean ablation depth was 50 (30-75) microns, and the single central ablation zone measured 6.0 mm in diameter. The postoperative refractive and visual outcome was favorable in most eyes. The mean postoperative refraction was -0.5 (-2.75 to + 0.5) D. Among the 25 eyes, 22 (88%) had +/- 1.0 D of attempted correction at 1 year and only 2 eyes showed a loss of 2 Snellen lines. Despite increased light scattering and reflection due to haze, sufficient postoperative imaging of the corneal nerve architecture was possible in all cases. Recovery of corneal innervation started from the margin of the ablation, being directed toward the center of the cornea and the epithelium. At 5-8 months following PRK, stromal nerves and the subepithelial nerve plexus took on their definite appearance. The original nerve structure was not reestablished, abnormal branching and accessory thin nerve fibers being present without exception. Confocal slit-scanning video-microscopy is a very useful technique for in vivo investigation of corneal nerve regeneration after PRK and, presumably, other keratorefractive procedures. In comparison with histology studies in animals, reinnervation of the human cornea after PRK seems to be completed earlier but follows the same morphologic principles.</p>","PeriodicalId":77146,"journal":{"name":"German journal of ophthalmology","volume":"5 6","pages":"373-7"},"PeriodicalIF":0.0,"publicationDate":"1996-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20404385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}