Radial keratotomy: 500 consecutive cases

Descemet membrane endothelial keratoplasty in a patient with iris-fixated intraocular lens and prior radial keratotomy: a case report

Background

Anterior segment surgeries such as cataract surgery, intraocular lens (IOL) repositioning, and radial keratotomy (RK) may hasten endothelial dysfunction, particularly in the context of pre-existing Fuchs dystrophy, necessitating future corneal transplantation.

Case presentation

A 68-year-old woman with a history of RK with associated irregular astigmatism in both eyes and iris-fixated intraocular lens (IF-IOL) in the left eye presented with six months of decreased vision in the left eye. She was found to have Fuchs dystrophy and underwent DMEK surgery. She had an uncomplicated postoperative course, with uncorrected visual acuity improving to 20/20 three months after surgery.

Conclusion

To our knowledge, this is the first reported case of a highly successful DMEK surgery in a patient with prior RK and IF-IOL.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-02103-1.

Descemet membrane endothelial keratoplasty for endothelial decompensation after previous radial keratotomy

Purpose

To report Descemet membrane endothelial keratoplasty (DMEK) for endothelial decompensation in an eye with previous radial keratotomy.

Observations

A history of radial keratotomy may hasten endothelial dysfunction. Previously reported surgical treatments include penetrating kerotoplasty and Descemet stripping automated endothelial keratoplasty.

Conclusions and Importance

DMEK may be successfully used in post-RK eyes with good recovery of visual acuity and patient satisfaction.

Late Onset Descemet Membrane Detachment after Radial Keratotomy Resolved with Medical Therapy

Purpose

To report a case of a Descemet membrane's (DM) detachment after radial keratotomy (RK).

Methods

A patient (male) underwent RK (16 cuts) 20 years before referring to the Eye Center of Humanitas (Milan) for a progressive visual loss. The slit-lamp examination showed severe corneal stromal edema and a large DM detachment in the lower half of the cornea. Anterior segment optical coherence tomography (AS-OCT) and endothelial cells count confirmed DM detachment and endothelial cells damage. Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) was planned and topical hypertonic therapy was prescribed before the surgery.

Results

Eight months later, the patient mentioned a spontaneous increase in visual acuity; the slit-lamp examination and the AS-OCT displayed a recovery of corneal transparency with a resolution of DM detachment.

Conclusions

This is the first report of spontaneous DM detachment with severe corneal edema after RK. We suggest that hypertonic therapy may reduce DM detachment and restore corneal transparency.

Night vision disturbances after corneal refractive surgery

A certain percentage of patients complain of "glare" at night after undergoing a refractive surgical procedure. When patients speak of glare they are, technically, describing a decrease in quality of vision secondary to glare disability, decreased contrast sensitivity, and image degradations, or more succinctly, "night vision disturbances." The definitions, differences, and methods of measurement of such vision disturbances after refractive surgery are described in our article. In most cases of corneal refractive surgery, there is a significant increase in vision disturbances immediately following the procedure. The majority of patients improve between 6 months to 1 year post-surgery. The relation between pupil size and the optical clear zone are most important in minimizing these disturbances in RK. In PRK and LASIK, pupil size and the ablation diameter size and location are the major factors involved. Treatment options for disabling glare are also discussed. With the exponential increase of patients having refractive surgery, the increase of patients complaining of scotopic or mesopic vision disturbances may become a major public health issue in the near future. Currently, however, there are no gold-standard clinical tests available to measure glare disability, contrast sensitivity, or image degradations. Standardization is essential for objective measurement and follow-up to further our understanding of the effects of these surgeries on the optical system and thus, hopefully, allow for modification of our techniques to decrease or eliminate post-refractive vision disturbances.

Laser in situ keratomileusis versus arcuate keratotomy to treat astigmatism

PURPOSE

To analyze the effectiveness of laser in situ keratomileusis (LASIK) and arcuate keratotomy (AK) to treat simple myopic, compound myopic, and mixed astigmatism.

SETTING

Instituto de la Visión, Buenos Aires, Argentina.

METHODS

This retrospective nonrandomized study comprised 821 cases treated with LASIK and 46 cases treated with AK. Patients were divided into 4 groups, which had the following preoperative cylinder corrections: simple myopic astigmatism (Group 1) (LASIK: n = 76, -3.91 diopters [D] +/- 1.29 [SD]; AK: n = 5, -3.85 +/- 0.65 D); compound myopic astigmatism up to 2.00 D (Group 2) (LASIK: n = 401, -1.69 +/- 0.76 D; AK: n = 14, -1.48 +/- 0.41 D); compound myopic astigmatism over 2.00 D (Group 3) (LASIK: n = 253, -3.61 +/- 0.89 D; AK: n = 16, -3.09 +/- 0.84 D); mixed astigmatism (Group 4) (LASIK: n = 91, +3.65 +/- 1.62 D; AK: n = 11, 4.39 +/- 0.92 D).

RESULTS

Six months postoperatively, the cylinder's vector-corrected change was as follows: Group 1, LASIK 3.75 +/- 1.08 D, AK 3.16 +/- 0.84 D; Group 2, LASIK 1.55 +/- 1.12 D, AK 1.34 +/- 0.44 D; Group 3, LASIK 3.39 +/- 0.98 D, AK 2.70 +/- 1.21 D; Group 4, LASIK 3.77 +/- 1.43 D, AK 3.75 +/- 0.89 D. Respective mean uncorrected visual acuities in each group were as follows: Group 1, 0.71 +/- 0.12 and 0.60 +/- 0.12; Group 2, 0.83 +/- 0.12 and 0.78 +/- 0.24; Group 3, 0.78 +/- 0.18 and 0.48 +/- 0.24; Group 4, 0.69 +/- 0.21 and 0.55 +/- 0.18.

CONCLUSIONS

The vector-corrected change and visual acuity achieved with LASIK were better, although not significantly, than those attained with AK except for the UCVA obtained with LASIK in eyes with compound myopic astigmatism over 2.00 D. Both methods proved to be safe.

Radial Keratotomy for Myopia From 5.00 to 13.00 Diopters Two Years After Surgery

BACKGROUND

Radial keratotomy for low myopia can produce good results with few side effects. For higher myopia, predictability becomes less accurate and side effects more common.

METHODS

A retrospective study of 111 eyes of 76 patients were divided into two groups. Group I had 79 eyes with myopia of -5.00 to -8.00 diopters (D); group II had 32 eyes with myopia -8.25 D to -13.00 D. One hundred eleven eyes were followed for 1 year and 90 eyes were followed for 2 years.

RESULTS

Sixty-seven (84.8%) eyes in group I and 12 (37.5%) eyes in group II achieved a refraction within the range of -1.00 D and +1.00 D. Ninety-two percent of group I and 44% of group II achieved an uncorrected visual acuity of 20/40 or better. Three percent lost spectacle-corrected visual acuity. Four eyes developed a hyperopic shift of 1.00 D or more between 2 months and 2 years. Seven other eyes developed a hyperopic shift of 1.00 D or more between 2 months and 5 years.

CONCLUSIONS

Eight-incision radial keratotomy is an attractive option for treatment of myopia up to -8.00 D. For levels above -8.00 D, the results are poorer; there may be a variable period before refraction stabilizes.

Stray light in radial keratotomy and the influence of pupil size and straylight angle

Glare is a major sequela of the radial keratotomy procedure. We used the straylight meter to measure intraocular light scatter, which is the cause of glare, in eyes after radial keratotomy. This apparatus uses a direct compensation method to assess the amount of intraocular light scatter. Nineteen patients were tested. Nine individuals served as controls. The mean postsurgery time was 60 months. The influence of the number of radial incisions, the pupil size, and the angle of light entering the eye were evaluated with the straylight meter. The results showed straylight values for normal pupil size (mean, 4 mm) to be statistically significantly higher (P = .0044) only for the smallest angle of light deflection studied (3.5 degrees). For dilated pupils (mean, 8 mm), straylight values were statistically significantly higher (P = .00005) for all three angles of light deflection studied. The number of incisions showed no statistically significant relationship to straylight values. Average stray light values were increased by a factor of 1.4 for 4-mm sized pupils and 2.0 for 8-mm sized pupils. There was an overlap in straylight values between the patient population and the control population.