Systems and methods for providing astigmatism correction
A method of selecting a toric lens by taking into consideration the magnitude and orientation of the posterior cornea and/or the location of the incision axis is described. The magnitude and orientation of the posterior cornea can be calculated as a function of the measured pre-operative orientation of the steep meridian of the anterior cornea.
1. A method of determining an optical power of a toric lens, the method comprising:
receiving a measurement related to an anterior corneal portion of an eye of a patient, the measurement obtained by an ophthalmic diagnostic device;
receiving information related to a position of an incision to be made in the eye of the patient for surgical purpose; and
calculating the optical power of the toric lens based only on the received measurement and the received position,
wherein the method is performed by a processor configured to execute instructions stored in a non-transitory computer medium which, when executed by the processor, cause the processor to calculate the optical power of the toric lens.
2. The method of claim 1 , wherein receiving the measurement related to the anterior corneal portion includes receiving an orientation of the steep meridian of the anterior corneal portion.
3. The method of claim 2 , wherein the calculating the optical power of the toric lens includes calculating a posterior corneal cylinder value due to posterior corneal astigmatism, the posterior corneal cylinder value determined by a function of a sine of the orientation of the steep meridian of the anterior corneal portion.
4. A method of determining an optical power of a toric lens, the method comprising:
receiving a measurement related to an anterior corneal portion of an eye of a patient, the measurement obtained by an ophthalmic diagnostic device;
receiving a measurement related to a posterior corneal portion of an eye of a patient, the measurement obtained by an ophthalmic diagnostic device;
receiving information related to a position of an incision to be made in the eye of the patient for surgical purpose; and
calculating the optical power of the toric lens based on the received measurement and the received position,
wherein the method is performed by a processor configured to execute instructions stored in a non-transitory computer medium which, when executed by the processor, cause the processor to calculate the optical power of the toric lens.
5. The method of claim 4 , wherein receiving the measurement related to the anterior corneal portion includes receiving an orientation of the steep meridian of the anterior corneal portion.
6. The method of claim 4 , wherein the calculating the optical power of the toric lens includes calculating a value for surgically induced astigmatism, the surgically induced astigmatism value given by a function of a sine of the orientation of the steep meridian of the anterior corneal portion and a function of the position of the incision.