Biomedical subjects

C Swinger

Publications and source records attributed to C Swinger.

6 recordsLinked to original sources

PubMed1990

Histopathology of human keratorefractive lenticules.

Eight human corneal lenticules (three from keratophakia, two from hypermetropic keratomileusis, and three from myopic keratomileusis) were examined by light and electron microscopy. The keratophakic lenticules were removed for optical reasons 3, 3.5, and 6 months after surgery. Microscopically, all displayed hypocellularity, mature collagen fibrils and microfibrils, keratocyte ghosts, and keratocytic debris. The hypermetropic keratomileusis specimens were removed at 13 and 14 months postoperatively, the first because of opacities from enzymatic digestion of the cornea, and the second due to contact lens-induced erosion of Bowman's layer and decreased lacrimal secretion. Ultrastructurally, both lenticules exhibited fractures in Bowman's layer, and the 14-month specimen showed multilayered squamous epithelia. The myopic keratomileusis specimens were removed at 4, 8, and 48 months postoperatively due to opacification of the interface caused by delayed epithelial healing, detergent trauma, and previous epithelization, respectively. Electron microscopy revealed fractures in Bowman's layer, subepithelial fibrocellular growth, sparse keratocyte populations of the anterior stroma, porous collagen bundles, keratocytic debris, and regions of epithelial ingrowth.

Adult↗

PubMed1986

Four-incision radial keratotomy for low to moderate myopia.

The first 112 consecutive eyes (75 patients) to undergo four-incision radial keratotomy (RK) performed by four surgeons were evaluated retrospectively. The preoperative myopia (spherical equivalent) ranged from -1.12 to -7.00 D (95% between -1.12 and -4.25 D). The preoperative uncorrected visual acuity was 20/100 or worse in 95% of the eyes. A six-month follow-up was achieved in 95% of the eyes and 45% were followed over one year. Following four incision RK, 79% of the eyes achieved 20/40 or better vision and 82% were corrected to within 1 D of emmetropia. Following repeat RK in 15 eyes (13%), 82% had uncorrected visual acuity of 20/40 or better, and 90% were corrected to within 1 D of emmetropia. Only 3.5% of the eyes were overcorrected by more than 1 D and only one eye had induced astigmatism greater than 1 D. For eyes with preoperative myopia up to -4.25 D over 90% achieved uncorrected visual acuity of 20/40 or better and were within 1 D of emmetropia following primary four incision RK and a second four incisions in 13 eyes (12%). Only 3.5% of the eyes in this group were overcorrected by more than 1 D. There were no serious complications.

Adult↗

PubMed1982

Refractive keratoplasty. Keratophakia and keratomileusis.

Early experience with the refractive keratoplasty techniques of José Barraquer--keratophakia and hypermetropic keratomileusis is presented. In contradistinction to the alloplastic lens substitutes currently being employed for the integral correction of aphakia, Barraquer's techniques would seem to offer a more permanent, more physiologic, full-time optical correction of the aphakic state. Their use is limited only by the condition of the patient's cornea and, in fact, may be applied not only in aphakia but also in phakic eyes with higher degrees of hyperopia or myopia. In the opinion of the authors, the refractive keratoplasty techniques of Barraquer can be performed by any well-instructed ophthalmic surgeon. These techniques offer to many patients a satisfactory, and potentially a physiologically superior alternative to alloplastic lens substitute for aphakic correction.

Aged↗

PubMed1981

Keratophakia update.

Since October 1977, the authors have attempted 32 keratophakias (refractive corneal surgery using an interlamellar homograft disc). Twenty-nine of these were primary and three secondary on aphakic eyes. These cases were divided into two series. In the first series, the dioptric correction was 28.5% less than the amount calculated to correct the aphakic error. In the second series, only 6.5% of the calculated dioptric power remained uncorrected. Keratophakia is an alternative to other modalities of secondary full-time correction of aphakia since the internal eye is not compromised by this secondary procedure as it is with a secondary intraocular implant. Further improvements in instrumentation techniques and mathematic programs will broaden the application of refractive keratoplasty techniques.

Adult↗

PubMed1980

Relaxing incision for control of postoperative astigmatism following keratoplasty.

A new technique has been presented which provides a second surgical approach to correct excessive residual astigmatism following keratoplasty. The relaxing incision procedure has advantages over wedge resection in that it can be performed at the slit lamp, it gives no initial overcorrection, and it has a much shorter postoperative course while giving rapid results without suturing. Since this technique does not appear to produce significant hyperopia and may produce a tendency toward myopia, the corneal surgeon would thus have alternative techniques from which to choose, depending, in part, on the spherical component of the refraction.

Astigmatism↗

PubMed1978

Refractive keratoplasty: keratophakia and keratomileusis.

We have presented our early experience with the refractive keratoplasty techniques of Doctor Jose Barraquer--keratophakia and hypermetropic keratomileusis. In contradistinction to the alloplastic lens substitutes currently being employed for the integral correction of aphakia, his techniques would seem to offer a more permanent, more physiologic, full-time optical correction of the aphakic state. Their use is limited only by the condition of the patient's corneaa and, in fact, may be applied not only in aphakia but also in phakic eyes with higher degrees of hyperopia or myopia. In the opinion of the authors, the refractive keratoplasty techniques of Barraquer can be perfored by any well-instructed ophthalmic surgeon. These techniques offer to many patients a satisfactory and potentially a physiologically superior alternative to alloplastic lens substitute for aphakic correction.

Aged↗