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C L Schepens

Publications and source records attributed to C L Schepens.

215 records · Page 12Linked to original sources
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Scleral implants: an historical perspective.

Scleral implants are made of absorbable or nonabsorbable materials. One category of absorbable materials consists of donor tissue, either autogenous (fascia lata, plantaris gracilis tendon) or from cadavers (dura mater, sclera, fascia lata). A second category includes gelatin, reconstituted collagen, absorbable gut, fibrin, blood plasma, air, and sodium hyaluronate; of these, specially prepared gelatin seems to be the most useful. Nonabsorbable implant materials have proven more practical than absorbable implants. Solid silicone rubber is currently the most popular scleral implant material. It is soft, easy to handle, and well tolerated. Expandable implants, either temporary or permanent, are used in the form of a silicone balloon filled with liquid. Silicone sponge, also widely used, has the advantage of great softness. However, hydrogels seem to be the ideal scleral implants. The only one commercially available is Refojo's MAI implant. It is very soft and is not damaged by sutures, has a smooth surface, is molded in several sizes and shapes, and has small pores that microorganisms cannot penetrate. When saturated with a water-soluble antibiotic before implantation, this implant releases the antibiotic postoperatively for a longer time than any other implant material. Finally, surgical adhesives are useful when the sclera is too thin or weak to tolerate sutures. The best adhesive available seems to be isobutyl cyanoacrylate.

Biocompatible Materials↗
PubMedDate not supplied

Diffuse choroidal thickening detected by ultrasonography in various ocular disorders.

Diffusely thickened choroid was detected ultrasonically in 207 eyes in various conditions, including: following intraocular surgery (108 eyes), trauma (8 eyes), phthisis bulbi (52 eyes), endophthalmitis (12 eyes), and nanophthalmos (27 eyes). Diffusely thickened choroid was seen by A-scan as a widening of the echo pattern originating from the posterior coats of the eye and by B-scan as a curvilinear echo giving a double contour to the globe. Although B-scan characteristics of thickened choroid consisted of a smooth curvilinear echo in 196 eyes, this echo was irregular with multiple angulations in 11 eyes that had phthisis bulbi. The mechanisms suspected of choroidal thickening were ocular hypotony (sudden or chronic, 154 eyes), impaired drainage in the vortex system (41 eyes), and severe intraocular inflammation (12 eyes).

Adolescent↗
PubMedDate not supplied

Telescopic eyepieces in indirect ophthalmoscopy.

A new attachment that can be used with optimized ophthalmoscopes is described. Readily removable and interchangeable eyepieces containing small, lightweight Galilean telescopes approximately double the magnification. The influence of this device on some of the optical properties of binocular indirect ophthalmoscopy including magnification, field of view, brightness of the fundus image, and stereopsis, are reviewed briefly.

Humans↗
PubMedDate not supplied

[Static microperimetry with the laser scanning ophthalmoscope].

We have used the scanning laser opthalmoscope (SLO) with a personal computer to develop static microperimetry techniques. They allow to see in real-time on a television monitor the precise retinal localization of the stimulus and fixation. The testing is performed under strict conditions. The size of stimuli can vary between 6 and 30 minarc on a side. 255 different intensity levels are possible with the instrument. We have selected 12 of them, representing a logarithmic scale. Stimulus duration can vary between 50 and 500 ms. Examples of macular pathology including subretinal neovascularization, drusen and macular edema are given.

Humans↗
PubMedDate not supplied

Vitreous surgery.

Explore the source record for details and available documents.

Aged↗
PubMedDate not supplied

Retinal breaks in diabetic retinopathy: vitreoretinal relationships.

We retrospectively reviewed the eyes of 143 patients with tractional retinal detachment caused by diabetes that had been studied biomicroscopically, and, after some exclusions, divided them into two groups: those with retinal breaks (group 1) (16 patients, 16 eyes), and those without retinal breaks (group 2) (127 patients, 161 eyes). The group 1 eyes were further divided into three subgroups: those with retinal tears from limited anteroposterior vitreous traction (subgroup A), those with macular holes in an area without posterior vitreous detachment (subgroup B), and those with oval retinal holes anterior to the anteroposterior vitreous traction (subgroup C). Subgroup C comprised most of the eyes in group 1 (10 eyes) and was the only subgroup that we compared with group 2. Significant differences between subgroup C and group 2 were found in terms of the extent of tractional retinal detachment (P = .002) and the degree of preretinal fibrosis (P = .009). These data suggest that large tractional retinal detachments and extensive preretinal fibrosis are significant risk factors for the development of retinal breaks in proliferative diabetic retinopathy.

Diabetic Retinopathy↗
PubMedDate not supplied

Pars plana virectomy. Preoperative evaluation.

We have outlined the essential considerations in evaluating patients for closed vitrectomy and have attempted to show the importance of each. In general, we recommend closed virectomy under the following conditions: (1) vitreous opacities showing no resolution after six months of observation, (2) vision which is worse than 20/200 but has at least light perception with accurate projection, (3) there is no rubeosis iridis or glaucoma, (4) ultrasonography, ERG, and VER reveal a functional retina and optic nerve, and (5) the benefit outweighs the risk of surgery.

Electroencephalography↗