Biomedical subjects

M Kriegerowski

Publications and source records attributed to M Kriegerowski.

6 recordsLinked to original sources

PubMed1991

[Excimer laser keratomileusis for myopia correction. Results and complications].

Results of excimer laser keratomileusis in 26 myopic sighted eyes are presented. The follow-up was at least 9 months. The base-line refraction was -4.48 +/- 1.81 D (range: -1.4 to -9.25 D). After 3 months 85% were within +/- 1 D from the intended refraction. The such defined success rate after 6 months was 87.5%, after 9 months 88%, and after 12 months 92%. One month after surgery we found an overcorrection of +1.45 +/- 1.22 D decreasing to +0.27 +/- 0.94 D at three months, becoming an undercorrection of -0.24 +/- 0.76 D after six, and -0.32 +/- 0.69 D after nine months, and of -0.36 +/- 0.6 D after one year. Stability within the measurement error (+/- 0.25 D) appeared in 79% of the treated eyes six months after treatment. Three patients have been excluded from the study group because they did not follow the protocol. Subepithelial haze occurred in all patients, becoming most intense after 3 months, gradually clearing over the next months. With appropriate steroid medication, the refractive effect may be modulated. Complications as steroid glaucoma, recurrent erosion, loss of acuity, or extensive corneal scarring seem to be very rare.

Adult↗

PubMed1990

[Laser keratomileusis for correction of myopia].

Laser keratomileusis with the excimer laser (193 nm) is a new method of refractive surgery. With this procedure a thin lenticule is ablated from the central cornea with submicron precision. The refraction changes achieved in 13 eyes ranged from 1.5 to 7.5 dpt. With this correction 92% of the treated eyes were within 1.0 dpt either way at 3 months after surgery, but after 6 months this proportion decreased to 77%. The best-corrected visual acuity recovers within 1 months to preoperative values. In all patients a slight subepithelial haze was detected with the slit-lamp in the early postoperative phase, but cleared within 4-6 months to a clinically non-significant level.

Adult↗

PubMed1990

[The ablation behavior of various corneal layers].

The difference in structure of the corneal layers leads to an inhomogeneous reaction to photoablation with 193 nm excimer laser light. This is important for the calculation of photorefractive keratectomy (PRK) where only a thin layer (10-50 microns) of the cornea must be removed. Therefore, the ablation rate for the Bowman zone is 2.5 times lower than that for corneal stroma; the same value is found in Descemet membrane. In contrast, the ablation rate of the epithelium is 1.5 times higher. Based on these data it will be possible to achieve high precision with PRK.

Astigmatism↗

PubMed1989

[Partial external trabeculectomy].

The authors show that with the Excimer laser partial trabeculectomy can be performed, a procedure in which the juxtacanalicular meshwork is removed while the other layers remain untouched. It was proved in experiments on ten enucleated human eyes that at most 3% of the outflow resistance is localized in the uveal and sclerocorneal meshwork. The clinical applicability of partial trabeculectomy was demonstrated on five eyes.

Choroid Neoplasms↗

PubMedDate not supplied

Ablation rate of human corneal epithelium and Bowman's layer with the excimer laser (193 nm).

Laser keratomileusis is a laser-specific procedure whereby a layer of corneal tissue as thin as 10 microns or more is removed from the anterior surface. In most cases, the laser ablates not only Bowman's layer but also portions of the anterior stroma. The histologic evaluation presented shows that the ablation behavior of these two layers is not uniform: at a fluence of 205 mJ/cm2 in Bowman's layer, the ablation rate was 0.38 +/- 0.05 microns per pulse, whereas in stroma it amounted to 0.55 +/- 0.1 microns per pulse. In epithelium, the ablation rate was 0.68 +/- 0.15 microns per pulse, but decreased with deeper excisions. We discuss the consequences of these different ablation rates on the procedure of laser keratomileusis.

Cornea↗

PubMedDate not supplied

Excimer laser (193 nm) myopic keratomileusis in sighted and blind human eyes.

Ten blind and 13 sighted human eyes underwent excimer laser (193 nm) keratomileusis. The radiant exposure was 180 mJ/cm2 with an ablation zone diameter of 3.5 mm. The follow-up of the blind eyes ranged from 9 to 11 months, whereas that of the sighted eyes was at least 6 months. The intended refraction change was -3.0 and -5.0 D in the blind eyes and ranged from -1.5 to -7.0 D in the sighted eyes. After 3 months, 12 of 13 sighted eyes (92%) achieved a refraction between +/- 1.0 D, whereas after 6 months 77% of the refractions were in this range. Temporary subepithelial haze occurred in all eyes except some of the -3.0 D blind eyes. After 6 months, the subepithelial haze had resolved to a clinical non-significant level (trace to grade 0.5 haze), except in one eye that showed a focal scar.

Adult↗