Journal of Eye Diseases and Disorders

Advanced Tope-guided/Oculink PRK and CXL Beneficial for the Visual Outcome in Patients with Keratoconus, Corneal Ecstasia and Thin Corneas

Klajda Bardhi ^* , Jonid Bilbili and Minir Asani Department of Ophthalmologist, German Eye Clinic, Femto Refractive Suite and Vitreoretinal Surgery Hygeia Hospital, Tirana, Albania
^*Correspondence: Klajda Bardhi, Department of Ophthalmologist, German Eye Clinic, Femto Refractive Suite and Vitreoretinal Surgery Hygeia Hospital, Tirana, Albania, Tel: 00355673044532, Email:

Received: 12-Nov-2019 Published: 28-Nov-2019

Case Study

Purpose

Stop the keratoconus, ‘Halt’ the corneal thinning, reduce the irregular astigmatism and improve.

UCVA methods

6 years study and long period of follow up of the first patientsusually every 2-3 patients with KC every month almost 120 patients in 6 yrs. Tope- guided/oculink PRK performed with excimer Ex 500 and CXL with CCL 365 and Riboflavin used in approx. all the cases was Vibex Rapid-which is with the twice diffusion rate than the standard riboflavin.

Election of the candidates

Not all the patients can succeed this treatment the most probable are the early stages Kc 1, Kc 1-2, some of the cases with Kc 2 with not very high keratometry readings. The ablation should be maximum admitted conform the keratometry readings

Advanced topography guided/Oculink is generally limited to 50 μm maximum tissue removal – for a residual stromal depth at least 300 μm – guided by a corneal map. The map is created by multiple high-resolution computer images. This allows imaging of difficult corneas, even those with extreme cones or keratometry greater than 55D.

Treatment algorithms are then developed to flatten or steepen specific meridians as needed based on a best fit spere. Another point is Zernike values: it calculates for each Zernike polynomial a coefficient which describes the contribution of that polynomial to the height data. The relative contribution of the Zernike polynomial (tilt, astigmatism, focus, coma, spherical ablation) is displayed in numerical values. C4 and C12 should be equal otherwise the treatment is not computed available. Abnormal values will appear in red; in Kc for example the coma will be often increased.

Discussion

From 120 patients included in the study 75 were with Kc 1-2, 25 with Kc 1, 20 of them with irregular astigmatism and thin cornea who were not good candidates for Lasik/Femto Lasik (Figure 1). 54 from 75 with Kc 1-2 improve the vision with more than 3 lines, 8 of them improve with 1 line, 9 of them had a corneal haze island, and only 2 cases were not satisfied for their postop UCVA and continued with RGP, these were with Kc 2 and with keratometry reading up to 53D (Figure 2).

Figure 1. Keratometry readings before/6 years after treatment.

Figure 2. Before/6 years after treatment.

Cases with irregular astigmatism and Kc 1 VA were 20/20 in their majority. In 6 years study from 100 cases with Kc only 2 of them continued with rigid contact lenses but no progression of KC only that it was not obtained the max UCVA expected.

The others progression was stable. The cases with irregular astigmatism and thin corneas had a max UCVA and very satisfied of the quality of the vision [1-11].

Conclusion

Advanced Tope-guided (oculink) PRK+CXL+Vibex R is the most adequate method of stopping and improving the vision in patients with keratoconus, and in patients with irregular astigmatism, or thin corneas which are not good candidates for Lasik or Femto Lasik.

Tope-guided/oculink treatment in additional is a safer method for not having tardive complications. The goal of treatment is to flatten the steepest part of the cornea and to steepen the flattest part of it the target of this procedure- is not fully correction but visual improvement and ‘halting’ the progression.

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