Instruction document. Fitting recommendations

Transcription

1 Instruction document Fitting recommendations

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3 Table of Contents Terminology 4 Frame Parameters: 4 Fitting parameters 4 Wearing parameters 6 Fitting recommendation Hoya Single Vision range 8 Hoya Single Vision lenses and reference power 10 Hoya Single Vision lenses and prescribed prism 10 Wearing conditions for Nulux identity V+ 11 Fitting recommendation Hoya Progressive lenses 12 Hoya Progressive lenses and reference power 12 Hoya Progressive lenses and prescribed prism 13 Recommended fitting ranges for Hoyalux id Progressive lenses 14 Wearing conditions for Hoyalux id Progressive lenses 15 Recommended fitting ranges for Hoyalux Summit Progressive lenses 15 Wearing conditions for Hoyalux Summit Progressive lenses 15 Recommended fitting ranges for Amplitude Progressive lenses 15 Wearing conditions for Amplitude Progressive lenses 15 Fitting recommendation Hoya Indoor lenses 16 Hoya Indoor lenses and reference power 16 Hoya Indoor lenses and prescribed prism 17 Recommended fitting ranges for Hoyalux id Indoor lenses 18 Wearing conditions for Hoyalux id Indoor lenses 18 Recommended fitting ranges for conventional and TrueForm Indoor lenses 18 Wearing conditions for conventional and TrueForm Indoor lenses 18 3

4 Terminology Frame Parameters Frame and Fitting parameters A: The A-Size is the horizontal size of the frame as defined by the boxing system B: The B-Size is the vertical size of the frame as defined by the boxing system DBL: Distance between the lenses as defined by the boxing system The measurements are taken from the outer edge of the lens, which is approximately 1 or 2 mm (depends on the frame thickness) from the inside rim of the frame. Fitting parameters PD R PD L Pupil Distance PD R/L: Pupil distance for the right and left eye. This is measured from the centre of the pupil to the middle of the nose. They are measured with a ruler or pupillometer. 4

5 CD R CD L Centration Distance CD R/L: Centration distance for right and left eye, based on the frame. This is measured from the center of pupil to the middle of the bridge of the frame. Ideally, they are measured with VisuReal or VisuReal portable. Note: The monocular Pupil and Centration distances may not be equal, because the PD is fixed while the CD depends on the frame. EP R EP R EP L Eye Point Height EP R/L: Eye point height. Either defined from the tangent to the bottom rim or from the center of the vertical boxing system. 5

6 Wearing parameters Wearing parameters are based on the wearing condition of the frame. Wearing parameters are the preferred set of parameters for ordering individual Hoya lenses. The measurements have to be done with a natural head position and a natural body posture. FCD Frame Cornea Distance (FCD) The distance from the corneal apex to the eye rim plane (the connecting line between top bevel and bottom level in the line of sight in primary gaze position), should be measured in zero visual direction. WPA Wearer s Pantoscopic angle (WPA) The angle between the eye rim plane and the vertical in space when the patient is in a habitual head and body posture while looking in primary gaze position (also referred as to zero visual direction). 6

7 frame plane eye rim plane FFFA Frame Face Form Angle (FFFA) This is the angle between the eye rim plane and the frame plane. Given the importance of the wearing parameters, opticians need to include the following measurements when placing their order: CD R/L EP R/L WPA FCD FFFA Wearing parameters 7

8 Fitting recommendation Hoya Single Vision range The Hoya Single Vision lens range (i.e. Hilux, Hilux TF, Nulux and Nulux TF) needs to be fitted according to the centre of rotation of the eye. This means that the optical axis of the lens passes through the centre of rotation of the eye. For the vertical direction the centre of rotation of the eye condition can either be achieved by: Asking the patient to move his head in such a position that the frame plane is perpendicular to the ground. The pupil centres are marked with the patient eyes in zero visual direction (looking at an object straight ahead). 1. Dot the pupil centres, as they will mark the position of the optical centers for mounting. 2. Take the monocular fitting heights. Using a digital fitting device such as visureal or visureal portable. 1. Natural Head Position 2. Head position for measuring the vertical centration (frame plane perpendicular to the ground) 8

9 EP R EP L This does not apply for three specific single vision designs: Nulux identity V+, Nulux Sportive TrueForm and Nulux Active TrueForm. Nulux identity V+ and Nulux Sportive lenses have to be fitted as an individualized lens design using a digital fitting device such as Hoya visureal + to measure CD R/L and EP R/L, but also the individual parameters FCD, WPA and FFFA, which are important to get the maximum performance from the lens. These measurements have to be done under natural head position and natural body posture. Horizontally (CD R/L) - by measuring the centration distance for right and left, using the middle of the frame as reference system while respecting potential differences between right and left. Vertically (EP R/L) - the fitting points need to be positioned in the center of the pupil with the patient s eye in the zero visual direction and respecting the difference between the right and left eye. Nulux identity V+ after correct centration and mounting Nulux Sportive TrueForm after correct centration and mounting 9

10 Nulux Active TrueForm fitting: Horizontally (CD R/L) - by measuring the centration distance for right and left, using the middle of the frame as reference system and respecting the differences between right and left. Vertically (EP R/L) - the fitting points positioned in the center of the pupil with the patient s eye in the zero visual direction and respecting the differences between right and left. Nulux Active TrueForm after correct centration and mounting Hoya Single Vision lenses and reference power The only Single Vision lenses produced by Hoya that are delivered with reference power are: Nulux identity V+ Nulux Sportive TrueForm Both lens designs have applied reference power for sphere, cylinder and axis for far. Additionally, Nulux Sportive TrueForm comes with reference power for prism, even if no prism is ordered. This is due to the fact that Nulux Sportive TrueForm is designed for high curved frames that usually have a relatively high FFFA (average above 20 ). For this range it is important to consider prism reference power to make sure that in the position of wear there is prism balance when viewing an object straight ahead. Nulux identity V+ does not come with reference power for the prism value and base. It is necessary only to measure a prism in the case of prescribed prism. In this case, the prism value and base to be measured is the ordered prism and prism base. Hoya Single Vision lenses and prescribed prism Except for spherical Single Vision lenses (i.e. Hilux conventional), all Single Vision lenses with prismatic prescription are ordered with the necessary prism value. The prism is not generated by de-centration. In the case of prescribed prism, the fitting needs to be compensated by 0.25mm per 1 Δ prescribed prism in the opposite direction of the prism base. This takes into account the movement of the eyes into their resting position in the case of prismatic prescription. In the case of prescribed Prism for Nulux identity V+ there has to be a split in horizontal and vertical prisms. The horizontal prism component is considered by a shift of the back surface in relation to the front surface, this leads to a situation where the horizontal component does not require additional de-centration. The vertical prism component needs to be compensated by 0.25mm per 1Δ prescribed prism in the opposite direction of the prism base. This already needs to be considered during the ordering process as the fitting height needs to be supplied together with the compensated values. If this is not done, the METS calculation would return a wrong diameter, potentially leading to the problem that the lens will not cut out. 10

11 Prism and visureal When CD and EP measurements are taken with the visureal video measurement system, some additional information is necessary: visureal tower: When the prescription values are entered in the visureal tower, the system will automatically recalculate the de-centration horizontally and vertically. Please note that as for V+ and Sportive lenses the horizontal de-centration is done by Hoya, extra attention has to be paid to be sure that there is no double de-centration done horizontally. visureal portable and portable+: The prescription is not entered in this situation. For standard lenses the ECP has to re-calculate the values for ordering and mounting. For V+ and Sportive lenses the ECP has to re-calculate only the vertical de-centration, as the horizontal de-centration is done by Hoya. S: distance from the center of rotation of the eye to the back surface of the lens. d: de-centration value for monocular horizontal and vertical decentration adjustments d 0,25 mm => 1 Δ 1mm => 4 Δ Prism (Δ) = 100 x d / S d (de-centration value ) = S x Δ/100 S = 25 mm s Examples for Hilux TF, Nulux and Nulux TF Example for Nulux identity V+ EPr = 20 mm EPl = 20 mm CDr = 32 mm CDl = 33 mm EPr = 20 mm EPl = 20 mm CDr = 32 mm CDl = 33 mm Prescribed prims: 2Δ base out (180 ) on the right eye and 2 Δ base up (90 ) on the left eye For ordering and mounting the new values are: EPr = 20 mm CDr = 31, 5 mm EPl = 19, 5 mm CDl = 33 mm Prescribed prims: 2Δ base out (180 ) on the right eye and 2 Δ base up (90 ) on the left eye For ordering and mounting the new values are: EPr = 20 mm CDr = 32 mm EPl = 19, 5 mm CDl = 33 mm Wearing conditions for Nulux identity V+ Nulux identity V+ FCD ideal FCD range 12-13mm 7-25mm FFFA ideal 0-5 FFFA range 0-15 Prescribed Prism 11

12 Fitting recommendation Hoya Progressive lenses Horizontally Measure the centration distance for right and left eye, using the middle of the frame as reference system. Vertically - the fitting points are positioned in the middle of the pupil with the patient s right and left eye in the zero visual direction and the body in a natural position, and respecting the difference between the right and left eye. Hoyalux Progressive lens after correct centration and mounting Practical advice: Please keep in mind that any lowering of the fitting height will also lower the reading portion, making it more difficult to reach this reading portion. Simply choosing a shorter corridor will only change the problem area. It is more important to focus on the refraction procedure, as most refraction units are placed in room distance around 5 6 meter, sometimes even at 4 m. To reach full correction for infinite distance an additional check for real infinite distance needs to be performed. In general an additional -0.25D for infinite distance is needed. The recommended optometric procedure is to perform a subjective trial at the end of the far refraction. Set up the refraction in the trial frame and ask to look at a distant object located > 10 m. Comfort? Clarity? Present first, if it gets blurred, go back. If not, keep +0.25D, that means the patient accommodates, the refraction does not give the emmetropisation. If is refused, present D. Keep it if vision is clearer and comfortable. -If has been added to far refraction; have to be added to the addition value. Hoya Progressive lenses and reference power Hoya Progressive lenses can be split in four categories with respect to reference power. 1. Hoyalux id V+ progressive lenses include reference power for sphere, cylinder and cylinder axis for far as well as reference power for the Addition given for measurement either on the front surface or on the back surface. Note that when measuring the Addition power on the front or on the back, the difference between either the mean power of the near and the far can be used, or the most vertical meridian of the two. Additionally, note that no matter which surface has been chosen for the measurement, both measurements (near and far) need to be performed on the same surface. There will always be a prism measured in the prism reference point. In the case of prescribed prism it will be a combination of the thinning prism and the ordered prism. The prescribed prism is calculated to match the ordered prism. In the theoretical case of no thinning prism, one will exactly measure the ordered prism. In the case of no prescribed prism, there will only be the thinning prism to be measured, which is intended to be equal for right and left. This naturally leads to the conclusion that in case of breakage of one lens only, the other lens needs to be given as reference for reordering the broken lens. Otherwise Hoya cannot ensure that the thinning prism between right and left is equal. 2. Hoyalux TrueForm progressive lenses as well as conventional Hoyalux progressive lenses don t have the reference power system applied. For those lenses the ordered value has to be measured. This applies to the far power measurement, the prism reference power, as well as the Addition power measurement. For this progressive lens category the Addition has to be measured on the front surface. Either as the difference between near and far mean power or the difference between the two most vertical meridians. While the validation of the far power needs to be done with the back surface on the holder of the focimeter. 12

13 3. Hoyalux id InStyle and Hoyalux id LifeStyle don t have reference power system applied for the far power. The Addition power values can be measured on the front surface or on the back surface. Note that when measuring the Addition power on the front or on the back, the difference between either the mean power of the near and the far can be used, or the most vertical meridian of the two. Additionally note that no matter which surface has been chosen for the measurement, both measurements (near and far) need to be performed on the same surface. There will always be a prism measured in the prism reference point. In the case of prescribed prism it will be a combination of the thinning prism and the ordered prism. The prescribed prism is calculated to match the ordered prism. In the theoretical case of no thinning prism, one will exactly measure the ordered Prism. In the case of no prescribed prism, there will only be the thinning prism to be measured which is intended to be equal for right and left. 4. Hoyalux Sportive TrueForm comes with reference power for far, near and for the prism, even if no prism is ordered, this is due to the fact that Nulux Sportive TrueForm is designed for high curved frames that usually have a relatively high FFFA (average above 20 degrees). For this range it is important to consider prism reference power in order to make sure that in the position of wear there is prism balance when viewing an object straight ahead. Hoya Progressive lenses and prescribed prism For all progressive lenses a prescribed prism can only be gained by ordering the prescribed prism power. When fitting lenses with a prescribed prism, we need to separate two cases: 1. Hoyalux id V+ Progressive lenses In the case of prescribed Prism for Hoyalux id V+ progressive lenses it needs to be split in horizontal and vertical. The horizontal prism component does not require additional de-centration. Because it is considered a shift of the back surface in relation to the front surface, this leads to a situation where the horizontal component does not require additional de-centration. This has the benefit that the given centration data in the horizontal direction fully match the Pupil distance or Centration distance which is used to calculate the convergence/inset. Therefore the inset calculation as well as the compensation is more accurate compared to the other category. The vertical prism component needs to be recalculated and compensated. 0.25mm per 1Δ prescribed prism in the opposite direction of the prism base. S: distance from the center of rotation of the eye to the back surface of the lens. d: de-centration value for monocular horizontal and vertical decentration adjustments d 0,25 mm => 1 Δ 1mm => 4 Δ Prism (Δ) = 100 x d / S d (de-centration value ) = S x Δ/100 S = 25 mm s 13

14 This must be considered already during the ordering process as the fitting height needs to be given together with the compensated values, otherwise the METS calculation would return a wrong diameter which could lead to the problem that the lens will not cut out. 2. All conventional and TrueForm progressive lenses from the Hoyalux Summit series, the Amplitude Series, and Hoyalux id MyStyle, Hoyalux id InStyle and Hoyalux id LifeStyle. In the case of prescribed prism, the lenses need to be de-centered horizontally and vertically by additional 0.25mm per 1 Δ prescribed prism in the opposite direction of the prism base. This takes into account the movement of the eyes into their resting position in the case of prismatic prescription. Obviously for ordering the lenses with METS, EP R/L and PD R/L or CD R/L or need to be given with the compensated values in order to ensure that the delivered lenses will cut out. Examples for Conventional and TF PALs EPr = 20 mm EPl = 20 mm CDr = 32 mm CDl = 33 mm Prescribed prims: 2Δ base in (0 ) on the right eye and 3 Δ base up (90 ) on the left eye For ordering and mounting the new values are: EPr = 20 mm CDr = 32, 5 mm EPl = 19, 25 mm CDl = 33 mm Example for Hoyalux id PALs EPr = 20 mm EPl = 20 mm CDr = 32 mm CDl = 33 mm Prescribed prims: 2Δ base out (180 ) on the right eye and 3 Δ base up (90 ) on the left eye For ordering and mounting the new values are: EPr = 20 mm CDr = 31,50 mm EPl = 19, 25 mm CDl = 33 mm Prism and visureal When CD and EP measurements are taken with the visureal video measurement system, some additional information is necessary: visureal tower: When the prescription values are entered in the visureal tower, the system will automatically recalculate the de-centration horizontally and vertically. Please note that as for V+ and Sportive lenses the horizontal de-centration is done by Hoya, extra attention has to be paid to be sure that there is no double de-centration done horizontally. visureal portable and portable+: The prescription is not entered in this situation. For standard lenses the ECP has to re-calculate the values for ordering and mounting. For V+ and Sportive lenses the ECP has to re-calculate only the vertical de-centration, as the horizontal de-centration is done by Hoya. Recommended fitting ranges for Hoyalux id Progressive lenses Hoyalux id MyStyle V+ Hoyalux id MyStyle Hoyalux id InStyle Hoyalux id Life- Style V+ X-Act Hoyalux id Life- Style V+ Hoyalux id Life- Style default corridor Available corridor recommended min. EP system limitation EP Recommended min. distance to upper rim Min. accepted value to upper rim

15 Wearing conditions for Hoyalux id Progressive lenses Hoyalux id MyStyle V+ Hoyalux id MyStyle Hoyalux id InStyle Hoyalux id Life- Style V+ X-Act Hoyalux id Life- Style V+ Hoyalux id LifeStyle FCD ideal 12-13mm 12-14mm 12-14mm 12-13mm 12-14mm 12-14mm FCD range 7-25mm 9-25mm Not applicable 7-25mm Not applicable Not applicable WPA ideal WPA range Not applicable 0-25 Not applicable Not applicable FFFA ideal FFFA range Not applicable 0-15 Not applicable Not applicable Recommended fitting ranges for Hoyalux Summit Progressive lenses Hoyalux Summit Pro (conventional and TrueForm) Hoyalux Summit CD (conventional and TrueForm) recommended min. EP system limitation EP Recommended min. distance to upper rim Min. accepted value to upper rim 8 8 Wearing conditions for Hoyalux Summit Progressive lenses Hoyalux Summit Pro (conventional and TrueForm) Hoyalux Summit CD (conventional and TrueForm) FCD 12-14mm 12-14mm WPA FFFA Recommended fitting ranges for Amplitude Progressive lenses Amplitude (conv. and TrueForm) Amplitude Mini (conv. and TrueForm) Amplitude TrueForm Polarized Amplitude Mini TrueForm Polarized recommended min. EP system limitation EP Recommended min. distance to upper rim Min. accepted value to upper rim Wearing conditions for Amplitude Progressive lenses Amplitude (conventional and TrueForm) Amplitude Mini (conventional and TrueForm) FCD 12-14mm 12-14mm WPA FFFA

16 Fitting recommendation Hoya Indoor lenses Hoyalux id WorkStyle V+, Hoyalux id WorkStyle as well as Hoyalux Tact have to be fitted exactly in the same way Hoya progressive lenses are fitted. The exception in this category are Addpower (conventional and TrueForm) and Lecture B (conventional and TrueForm). Horizontally, they both need to be centred with the fitting point in front of the pupil at the main viewing distance for near. In a first good estimate this is around 2.5 mm nasal from the far pupil distance. However it is known that the convergence depends on multiple factors such as: Pupil distance Working distance Near power of the lens This can be also estimated by measuring PD R/L with a pupilometer set up at 40, 50 or 60 cm. Additionally the wearing condition of the chosen frame will impact the position where the main ray for near will pass through the lens in the worn condition. On the other hand this influence is relatively small if the frame is worn in a condition which is close to a standard wearing condition. For the measurement of the convergence you can use the simple mirror technique to mark the near point. While doing this, it is suggested to wear a frame with prescription lenses that are close the prescribed power. This will also help the patient to clearly see the mark on the mirror which he needs to focus on. Vertically, Addpower and Lecture B have to be fitted at the center of the pupil in zero gaze direction while the patient is in a natural head and body posture. Ideally this position would fall together with the horizontal center line of the frame. This has to be done to ensure that the near vision part as well as the total degression can be used in correctly. Additionally, it has to be noted that Addpower as well as Lecture B are ordered with the near power only while Hoyalux id WorkStyle V+, Hoyalux id WorkStyle and Hoyalux Tact are ordered with far power and addition power. Hoyalux id WorkStyle V+ lens after correct centration and mounting Hoya Indoor lenses and reference power The only Hoya Indoor lens that comes with reference power is Hoyalux id WorkStyle V+. The reference power is in line with the described logic of the Hoyalux id V+ progressive lenses. However, there will be a difference in checking power that also depends on the chosen design as well as the ordered prescription. For more details about the reference power of Hoyalux id WorkStyle V+, please refer to the product information of Hoyalux id WorkStyle V+. In the case of Tact 200 or Hoyalux id WorkStyle 200, the measured power will be: Measured Far Power = Ordered Far Power D Measured Addition Power = Ordered Addition Power 0.50D 16

17 Example calculation: Ordered Power Measured Power for Tact (400) Measured Power for Tact 200 Sphere 0.50D 0.50D 1.00D Addition 2.00D 2.00D 1.50D In the case of Addpower and Lecture B the ordered near power has to be measured in the near reference point, the prism has to be measured at the horizontal center line/fitting point. The degression can be measured 20mm above the fitting point. There will always be a prism measured in the prism reference point. In the case of prescribed prism it will be a combination of the thinning prism and the ordered prism, but in any case, the prescribed prism is calculated in a way that it matches the ordered prism. In the theoretical case of no thinning prism, one will exactly measure the ordered Prism. In the case of no prescribed prism, only the thinning prism is measured, which is equal for right and left. The logical conclusion is that in case of breakage of one lens, the other lens needs to be given as reference when reordering the broken lens. Otherwise Hoya cannot ensure that the thinning prism between right and left is equal. Hoya Indoor lenses and prescribed prism For all Hoya Indoor lenses a prescribed prism can only be gained by ordering the prescribed prism power. When fitting lenses with a prescribed prism, we need to separate two cases: 1. Hoyalux id WorkStyle V+ In the case of prescribed prism for Hoyalux id WorkStyle V+ we need to split in horizontal and vertical directions: The horizontal prism component is considered by a shift of the back surface in relation to the front surface. This leads to a situation where the horizontal component does not require additional de-centration. This has the benefit that the given centration data in the horizontal direction fully matches to the Pupil Distance or Centration Distance, which is used to calculate the convergence/inset. Therefore the inset calculation as well as the compensation is more accurate compared to the other category. The vertical prism component needs to be compensated by 0.25mm per 1 Δ prescribed prism in the opposite direction of the prism base. This needs to be considered already during the ordering process as the fitting height needs to be given with the compensated values. If this is not done, the METS calculation would return in an incorrect diameter, possibly leading to the problem that the lens will not cut out. 2. All conventional and TrueForm Indoor lenses (Addpower, Lecture B, Hoyalux Tact), as well as Hoyalux id WorkStyle. In the case of prescribed prism, the lenses need to be de-centered by additional 0.25mm per 1 Δ prescribed prism in the opposite direction of the prism base. This takes into account the movement of the eyes into their resting position. Obviously for ordering the lenses with METS, the EP R/L and PD R/L or CD R/L need to be given with the compensated values in order to ensure that the delivered lenses will cut out. Examples for Conventional and TF indoor lenses EPr = 20 mm EPl = 20 mm CDr = 32 mm CDl = 33 mm Prescribed prims: 2Δ base in (0 ) on the right eye and 3 Δ base up (90 ) on the left eye For ordering and mounting the new values are: EPr = 20 mm CDr = 32, 5 mm EPl = 19, 25 mm CDl =33 mm Example for Workstyle V+ EPr = 20 mm EPl = 20 mm CDr = 32 mm CDl = 33 mm Prescribed prims: 2Δ base out (180 ) on the right eye and 3 Δ base up (90 ) on the left eye For ordering and mounting the new values are: EPr = 20 mm CDr = 32 mm EPl = 19, 25 mm CDl = 33 mm Prism and visureal When CD and EP measurements are taken with the visureal video measurement system, some additional information is necessary: visureal tower: When the prescription values are entered in the visureal tower, the system will automatically recalculate the de-centration horizontally and vertically. Please note that as for V+ and Sportive lenses the horizontal de-centration is done by Hoya, extra attention has to be paid to be sure that there is no double de-centration done horizontally. visureal portable and portable+: The prescription is not entered in this situation. For standard lenses the ECP has to re-calculate the values for ordering and mounting. For V+ and Sportive lenses the ECP has to re-calculate only the vertical de-centration, as the horizontal de-centration is done by Hoya. 17

18 Recommended fitting ranges for Hoyalux id Indoor lenses default corridor Hoyalux id WorkStyle V+ 22 mm for Space and Screen design 20 mm for Close design Hoyalux id WorkStyle 24 Available corridor recommended min. EP system limitation EP Recommended min. distance to upper rim Min. accepted value to upper rim Wearing conditions for Hoyalux id Indoor lenses Hoyalux id WorkStyle V+ Hoyalux id WorkStyle FCD 12-13mm 12-14mm FCD range 7-25mm Not applicable WPA WPA range 0-25 Not applicable FFFA FFFA range 0-15 Not applicable Recommended fitting ranges for conventional and TrueForm Indoor lenses Hoyalux Tact (conv. and TrueForm) Lecture B (conv. and TrueForm) Addpower (conv. and TrueForm) recommended min. EP system limitation EP Recommended min. distance to upper rim Min. accepted value to upper rim Wearing conditions for conventional and TrueForm Indoor lenses Hoyalux Tact (conv. and TrueForm) Lecture B (conv. and TrueForm) Addpower (conv. and TrueForm) FCD 12-14mm 12-14mm 12-14mm WPA FFFA

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20 Fitting recommendations Publication date: