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J J Saragoussi

Publications and source records attributed to J J Saragoussi.

At least 19 recordsLinked to original sources
PubMed1991

[Damage to the corneal endothelium caused by radial keratotomy].

In our experimental study on 53 rabbits we compared the amount of corneal endothelial damage caused by radial keratotomy (RK) referred to (1) the number of incisions (4, 8, or 16), (2) the postoperative interval (0 h, 48 h) and (3) the direction of the incision [centripetal (cp), centrifugal (cf)]. The endothelial damage was quantified by means of the Janus green photometry technique. Morphological changes were evaluated by scanning electron microscopy (SEM). Depending on the group examined, we found endothelial damage extending over 3-7% of an analysed surface of 64 mm2. One perforation caused endothelial damage of up to 17% of the surface examined. Increasing the number of incisions from 4 to 8 or 16 resulted in a statistically significant increase in the amount of endothelial damage (4.2%, 5.1%, 5.8%; P less than 0.05). At 0 h it was significantly higher than after 48 h (5.5%, 4.6%; P less than 0.05). The direction of the incision had no statistically significant influence in our study (zp: 5.2%, zf: 4.9%). The morphological changes in the rabbit corneal endothelium examined directly after the RK procedure were ruptures in the cell membranes, loss of cells, and posterior corneal protrusions beneath the incisions. After 48 h, we found fewer damaged cells and no denuded Descemet's membranes, but larger polymorphy of the cells and a numerical increase in the microvilli of the cells surrounding the damaged cells. Our results support the crucial argument against RK: the alteration and destabilization of healthy corneal tissue up to the endothelium.

Animals↗
PubMed1990

[Results of transverse incisions in surgical correction of severe post-keratoplasty astigmatism].

Results of a clinical study concerning 40 consecutive cases of high post-keratoplasty astigmatism corrected by the transverse keratotomy technique are presented and analysed. The protocol was determined for each case by keratometry and a qualitative analysis of the anterior corneal topography. The mean preoperative cylinder was 8.60 +/- 2.31 D. The mean postoperative cylinder was 4.79 +/- 1.82 D. The mean cylinder change was 4.40 +/- 2.92 D. In a majority of cases the corrected visual acuity (for distance and reading vision) was improved. There was no change in the spherical equivalent value. The main drawback of the procedure is its poor predictability. The procedure is effective in this indication and relatively safe.

Adult↗
PubMed1990

Radial keratotomy.

Radial keratotomy is effective for correcting low-grade myopia. The predictability is best for myopia that is less than 4 diopters. If the procedure is well performed, the rate of complications remains low. There is not always good correlation between refraction and keratometric changes because of correction errors, which are the main complication. Glare and fluctuating vision are common in the weeks following surgery. Wound healing may be delayed. Histological studies have shown that the epithelial plug is sometimes not eliminated after 4 years, which explains the long-term changes in refraction and corneal fragility after trauma. Incision ruptures can occur many years after surgery. The long-term evolution after 10 years is not known, and the indications are still controversial because it is a surgical procedure that modifies the visual function of a healthy eye.

Humans↗
PubMed1989

[Corneal refractive surgery].

During the past 8 years surgery of the cornea for refractive errors has risen to the rank of an independent, specialized discipline. It covers a range of techniques devised to correct or reduce all types of ametropia. Radial keratotomv is the operation most frequently performed to correct mild or moderate myopia from -1 to -6 diopters. Keratomileusis with or without freezing is a more complex procedure used to correct severe myopia of -8 to -16 diopters. Epikeratophakia for myopia or hypermetropia has a wider range of correction, ranging from 5 to 30 diopters. Each of these techniques has its own possibilities, limitations and risks. The main problem in this type of surgery if the predictability of its results. It is indicated essentially for cases where contact lenses have proved useless or are contra-indicated.

Aphakia↗
PubMed1988

[Lamellar keratoplasty with the Barraquer microkeratome. Preliminary clinical study apropos of 7 cases].

The authors report the results of a preliminary clinical study about lamellar keratoplasty performed with the Barraquer microkeratome. Seven eyes were operated on by this technique, with good functional and anatomical results. Nevertheless, some problems remain. An accurate diameter of the resected button, concerning both the donor and recipient corneas cannot be exactly predicted. There may also exist some irregularities at the edges of the resection. For these reasons, a good incorporation of the donor cornea into the recipient bed may be difficult. These are the main problems with this technique, which facilitates an improved visual prognosis of lamellar keratoplasty.

Adolescent↗
PubMed1988

[Results of myopic keratomileusis. A retrospective clinical study apropos of 40 cases].

The authors report in a retrospective study, the results of myopic keratomileusis. 40 eyes were operated on at the department of ophthalmology of Hotel-Dieu Hospital in Paris, with a range follow-up of 6 to 24 months. The mean pre-operative spherical equivalent was - 15.08 +/- 3.32 D., and the mean post-operative spherical equivalent was - 5.02 +/- 3.75 D. relative to preoperative conditions, best corrected visual acuity were unchanged in 6 cases, improved in 16 cases and diminished in 18 cases. The predictability of results was better for patients with myopia in the range of - 9 to - 16 D. During the first post-operative year, a mean regressive tendency of 3 diopters was noted. Complications are reported and analysed. Myopic keratomileusis is indicated for myopia between - 10 and - 16 D., when correction by contact lenses has failed. Candidates for surgery must be informed and consent about possibilities, limits and risks of the procedure.

Cornea↗
PubMed1987

[Use of cyclosporin A eyedrops in the prevention of corneal graft rejection in man. I. Preoperative development of 4 eyes with metaherpetic keratitis].

Topical cyclosporine A (2%) has been used to prevent corneal graft rejection in high risk patients. The treatment was begun 48 h at least before surgery. 3 patients (4 eyes) suffering from metaherpetic keratitis were placed under this treatment for a long time due to the delay to obtain a corneal donor. Their observation while treated showed a remarkable slow-down of the inflammation both in conjunctivae and corneas. This confirms if necessary the role of T lymphocytes in metaherpetic corneal diseases and the clinical modulation effect of cyclosporine A on these T cells.

Administration, Topical↗
PubMed1987

Excimer laser experimental keratectomy. Ultrastructural study.

Excimer lasers have been shown to produce precise etching and clean incisions of the cornea. On two freshly enucleated human eyes radial incisions and a myopic keratomileusis were performed with a specially designed delivery system. The cornea was then studied by transmission and scanning electron microscopy. The surface of the irradiated area was extraordinarily smooth and clean with a precision greater than 10 nm. The epithelial cells were literally cleaved by the ablation process. The cytoplasm and the nucleus were cut without any damage to the other part of the cell and no disturbance of the cells proximal to the incision. The corneal stroma was cut in a regular and smooth fashion, and the aspects observed with the scanning electron microscope differed mainly from the surface observed after an incision made with a diamond knife. The excimer laser allowed optimal conditions for quick and safe wound healing but the long-term effects on the epithelial cells must be evaluated by further studies.

Cornea↗