C.8.25.8 Lensometry Measurements Module

Table C.8.25.8-1 defines the Attributes used to capture the refractive measurements by a lensometer for spectacles. This is typically for a pair of lenses, but sometimes for just one. Sometimes a single lens is measured with an unknown laterality.

Table C.8.25.8-1LENSOMETRY MEASUREMENTS MODULE ATTRIBUTES

Attribute Name Tag Type Attribute Description
Lens Description (0046,0012) 2 A free text description of the lens and lens general comments. Note: A common example is to identify the specific spectacles measured
Right Lens Sequence (0046,0014) 1C A sequence that specifies measurements of a patient’s right lens. Required if the right lens is measured. Only a single Item shall be included in this sequence.
>Include 'Lensometry Measurements Macro' Table C.8.25.8-2
Left Lens Sequence (0046,0015) 1C A sequence that specifies measurements of a patient’s left lens. Required if the left lens is measured. Only a single Item shall be included in this sequence.
>Include 'Lensometry Measurements Macro' Table C.8.25.8-2
Unspecified Laterality Lens Sequence (0046,0016) 1C A sequence that specifies measurements of one lens of unknown laterality. Only a single Item shall be included in this sequence. Shall not be included if Attribute Right Lens Sequence (0046,0014) or Left Lens Sequence (0046,0015) is present. Required if a single lens of unknown laterality is measured.
>Include 'Lensometry Measurements Macro' Table C.8.25.8-2

Table C.8.25.8-2 describes the attributes for the Lensometry Measurements Macro.

Table C.8.25.8-2 LENSOMETRY MEASUREMENTS MACRO

Attribute Name Tag Type Attribute Description
Sphere Power (0046,0146) 1 Refractive power of the lens that is the same in all meridians, measured at distance (optical infinity), in diopters.
Include 'Cylinder Sequence Macro' Table C.8.25.6.1-1
Add Near Sequence (0046,0100) 1C A sequence that specifies refractive measurements of the lens to correct for inability to focus at near while wearing the distance prescription. Only a single item shall be included in this sequence. Required if Add Near is measured in the lens.
>Add Power (0046,0104) 1 Additional power relative to the distance correction, expressed in diopters, that allows best corrected visual acuity at the defined viewing distance.
>Viewing Distance (0046,0106) 3 The distance, in cm, for testing visual acuity corresponding to the value of Add Power (0046,0104) in this sequence.
Add Intermediate Sequence (0046,0101) 1C A sequence that specifies refractive measurements of the lens to correct for inability to focus at intermediate distance while wearing the distance prescription. Only a single item shall be included in this sequence. Required if Add intermediate is measured in the lens.
>Add Power (0046,0104) 1 Additional power relative to the distance correction, expressed in diopters, that allows best corrected visual acuity at the defined viewing distance.
>Viewing Distance (0046,0106) 3 The distance, in cm, for testing visual acuity corresponding to the value of Add Power (0046,0104) in this sequence item.
Include ‘Prism Sequence Macro’ Table C.8.25.6.2-1
Lens Segment Type (0046,0038) 3 The type of segment of a lens containing the “add” power, as described above Enumerated Value: PROGRESSIVE NONPROGRESSIVE
Optical Transmittance (0046,0040) 3 The fraction of light that passes through the measured lens optical media, in percent.
Channel Width (0046,0042) 3 In a progressive lens, the width in mm of that portion of the lens where there is gradual or progressive increase in “add” power. Note: See Attributes, Add Near Sequence (0046,0100) and Add Intermediate Sequence (0046,0101) for description of“add”.