Ординатура / Офтальмология / Английские материалы / Jaypee Gold Standard Mini Atlas Series CORNEALTOPOGRAPHY_Agarwal, Jacob_2009

MINI ATLAS SERIES: CORNEAL TOPOGRAPHY

FIGURE 10.7: Preoperative corneal topography of patient with keratoconus

the cornea. Figure 10.9 shows post-CK slit lamp view of the patient with keratoconus.

At this time the patient, happy and satisfied, asked to have surgery performed on the other eye. This case demonstrates that CK can be used to treat irregular astigmatism even though it requires additional follow-up, as well as standardization of nomograms for such cases.

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FIGURE 10.8: The location on the cornea at which the CK spots were placed for the patient with keratoconus

Case 2. CK for Post-cataract Surgery Astigmatism

A 71 years old patient came to the institute with a “visual problem” in the left eye. A phacoemulsification (sutureless) with the insertion of an Acrysof lens (Alcon) had been performed in another hospital. Uncorrected VA in the left eye was 20/50, BCVA was 20/30, and cylinder was + 1.5 D @ 70°. Corneal topography revealed regular post-cataract astigmatism (Fig. 10.11). We did not know if the astigmatism had been induced by the incision, but it was

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MINI ATLAS SERIES: CORNEAL TOPOGRAPHY

FIGURE 10.9: Post-CK corneal topography of patient with keratoconus

FIGURE 10.10: Post-CK slit lamp view of patient with keratoconus

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FIGURE 10.11: Preoperative corneal topography of patient with regular post-cataract surgery astigmatism

not relevant to our treatment plan. After studying the topography map, I decided to place two spots, one in each flat axis, at the 7 mm optical zone (Fig. 10.12). The post-CK corneal topography (Fig. 10.13) shows no astigmatism, and the patient now has UCVA of 20/30 and a plano refraction, stable at the last examination (6 months). This case illustrates that Conductive Keratoplasty can be effective

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FIGURE 10.12: Location of CK spots placement of patient with postcataract surgery astigmatism

for treatment of post-cataract surgery patients (hyperopic or astigmatic).

SUMMARY

Conductive keratoplasty is a non-laser procedure for changing corneal curvature to treat presbyopia, low to moderate spherical hyperopia, and other refractive conditions. The largest potential population for CK appears to be the presbyopes, many of whom are interested in a

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CHAPTER 10: CONDUCTIVE KERATOPLASTY

FIGURE 10.13: Post-CK corneal topography of patient with postcataract surgery astigmatism

non-laser procedure that can extend the period of spectaclefree near vision.

Depth perception was maintained, binocular corrected distance acuity was better than preoperative level for 20/ 20, 20/32, and 20/40 acuities, and there was no loss of contrast sensitivity (quality of vision) from preoperative levels. Furthermore the presbyopia patient study showed

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that approximately 9/10 patients could see both 20/20 or better binocularly at distance and J3 or better at near without glasses. Patient satisfaction was high and 98% reported improvement in quality of vision. The procedure was remarkably safe with only 1% showing a transient loss of > 2 lines of BSCVA.

Conductive Keratoplasty also has potential in the treatment of conditions other than hyperopia or presbyopia. The treatment plan for these must be designed by the surgeon for the patient’s particular condition. At the Institute (Istituto Laser Microchirurgia Oculare, Brescia, Italy) we are treating keratoconus and astigmatism in postcataract surgery patients by placing treatment spots on specifically chosen locations on the cornea. Other conditions we are studying and treating at the Institute are: (1) post-LASIK hyperopia performing CK spots on the flap (the effect seems to be more powerful compared to the CK applied to the virgin eye); (2) post-PRK hyperopia applying the CK spots only if we have enough pachimetry in 7/8 mm. optical zone; (3) post-PRK astigmatism (regular or irregular) and post-phakic IOL’s hyperopia (here it is more easy being the cornea in a virgin condition). Conductive keratoplasty appears very promising for treating presbyopia and hyperopia, as well as a number of less common refractive conditions, easily, effectively, and safely.

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Of course, a longer follow-up is needed in order to evaluate the long-term stability, effects and efficiency of this interesting technique in time.

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