Keratoconus

hydrocone-logo hydroconeP-logo

The HydroCone are a custom made soft keratoconus contact lenses with an unique design. The patented dynamic stabilization retain the same oxygen supply at the limbus comparing a standard  prismatic contact lens. This soft keratoconus contact lenses are available as a single vision, but also in a multifocal version. Depending on the stage of the keratoconus, the HydroCone is available for early and advance stage keratocone. The design provides the patients with comfort as a standard soft contact lens and visual acuity similar to rigid lenses.

Geometrie

  • Spherical back optic zone with strong aspheric flattening
  • Front toric optic zone
  • Dynamic stabilisation with bumps nasal and temporal
  • Optimised centre thickness

hydrocone

HydroCone-vials

Variations

hydrocone-12-logo keratoconus of degrees 1 to 2

hydrocone-34-logo keratoconus of degrees 3 to 4

HydroCone P

Multifocal-torical front optic zone in Bifocal (Bf) /  Simple progressive (Sp) /  Multi progressive (Mp)

Technical data

  • Total diameter: 12.00 -> 15.00 mm
  • Base curve: 7.00 -> 12.00 mm
  • Sphere: -40.00 -> + 40.00 dpt
  • Cylinder: -0.25 -> -8.00 dpt
  • Axe: 0° -> 180°
  • Addition: +0.50 ->+4.00 dpt
  • Central optical zone Zoc: 1.00 -> 4.50 mm
  • Flattening: (+) K12/ (+) K34

steps 0.01 mm / 0.01 dpt / 1°

First fitting

We suggest working with trial lenses with cyl −0.01 dpt.

Keratoconus classification

First apply the topographic indications or the following rules:

  • Vcc > 0.6 and/or keratometry > 6.80 mm: grade 1 or 2 (HydroCone K12)
  • Vcc < 0.6 and/or keratometry < 6.80 mm: grade 3 or 4 (HydroCone K34)

Diameter and base curve: 1st trial lens

  • HydroCone K12: rO = 8.00 / ØT = 14.00 mm
  • HydroCone K34: rO = 7.80 / ØT = 13.70 mm

Advice

  • The first trial lens helps to validate rO / ØT.
  • Dynamic stabilisation marks are needed to measure the stabilisation axis
  • The power (F’v) is spherical because part of the correction is made by the tear film and can’t be anticipated. The final cylinder corresponds to the residual astigmatism.
  • F’v for the trial lens order: spectacle sphere (adjust BVD = 0) with −0.01 dpt × 180° cylinder
  • For changes and control over several months always use the initial (genesis) lens for over refraction.
  • Use upper and lower eyelids to remove the contact lens.
  • By halo, increase optic zone diameter
  • Measurement of the residual astigmatism with autorefractometer plus subjective refractometry.
  • Due to geometry, the contact lens can slip a little bit to the bottom.
  • Increasing centre thickness can improve the visual acuity.
  • HydroCone P fitting: initially fit with HydroCone (single vision toric lens) then add progression in a second step.

Materials: Silikon-Hydrogel Definitive 74%, Igel 77%

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